211 research outputs found
The DEEP Groth Strip Galaxy Redshift Survey. III. Redshift Catalog and Properties of Galaxies
The Deep Extragalactic Evolutionary Probe (DEEP) is a series of spectroscopic
surveys of faint galaxies, targeted at the properties and clustering of
galaxies at redshifts z ~ 1. We present the redshift catalog of the DEEP 1 GSS
pilot phase of this project, a Keck/LRIS survey in the HST/WFPC2 Groth Survey
Strip. The redshift catalog and data, including reduced spectra, are publicly
available through a Web-accessible database. The catalog contains 658 secure
galaxy redshifts with a median z=0.65, and shows large-scale structure walls to
z = 1. We find a bimodal distribution in the galaxy color-magnitude diagram
which persists to z = 1. A similar color division has been seen locally by the
SDSS and to z ~ 1 by COMBO-17. For red galaxies, we find a reddening of only
0.11 mag from z ~ 0.8 to now, about half the color evolution measured by
COMBO-17. We measure structural properties of the galaxies from the HST
imaging, and find that the color division corresponds generally to a structural
division. Most red galaxies, ~ 75%, are centrally concentrated, with a red
bulge or spheroid, while blue galaxies usually have exponential profiles.
However, there are two subclasses of red galaxies that are not bulge-dominated:
edge-on disks and a second category which we term diffuse red galaxies
(DIFRGs). The distant edge-on disks are similar in appearance and frequency to
those at low redshift, but analogs of DIFRGs are rare among local red galaxies.
DIFRGs have significant emission lines, indicating that they are reddened
mainly by dust rather than age. The DIFRGs in our sample are all at z>0.64,
suggesting that DIFRGs are more prevalent at high redshifts; they may be
related to the dusty or irregular extremely red objects (EROs) beyond z>1.2
that have been found in deep K-selected surveys. (abridged)Comment: ApJ in press. 24 pages, 17 figures (12 color). The DEEP public
database is available at http://saci.ucolick.org
The novel mu-opioid antagonist, GSK1521498, reduces ethanol consumption in C57BL/6J mice.
RATIONALE
Using the drinking-in-the-dark (DID) model, we compared the effects of a novel mu-opioid receptor antagonist, GSK1521498, with naltrexone, a licensed treatment of alcohol dependence, on ethanol consumption in mice.
OBJECTIVE
We test the ability of GSK1521498 to reduce alcohol consumption and compare its intrinsic efficacy to that of naltrexone by comparing the two drugs at doses matched for equivalent receptor occupancy.
METHODS
Thirty-six C57BL/6J mice were tested in a DID procedure. In 2-day cycles, animals experienced one baseline, injection-free session, and one test session when they received two injections, one of test drug and one placebo. All animals received GSK1521498 (0, 0.1, 1 and 3Â mg/kg, i.p., 30Â min pre-treatment) and naltrexone (0, 0.1, 1 and 3Â mg/kg, s.c. 10Â min pre-treatment) in a cross-over design. Receptor occupancies following the same doses were determined ex vivo in separate groups by autoradiography, using [3H]DAMGO. Binding in the region of interest was measured integrally by computer-assisted microdensitometry and corrected for non-specific binding.
RESULTS
Both GSK1521498 and naltrexone dose-dependently decreased ethanol consumption. When drug doses were matched for 70-75Â % receptor occupancy, GSK1521498 3Â mg/kg, i.p., caused a 2.5-fold greater reduction in alcohol consumption than naltrexone 0.1Â mg/kg, s.c. Both GSK1521498 and naltrexone significantly reduced sucrose consumption at a dose of 1Â mg/kg but not 0.1Â mg/kg. In a test of conditioned taste aversion, GSK1521498 (3Â mg/kg) reduced sucrose consumption 24Â h following exposure to a conditioning injection.
CONCLUSIONS
Both opioid receptor antagonists reduced alcohol consumption but GK1521498 has higher intrinsic efficacy than naltrexone
Atmospheric methane variability: Centennial-scale signals in the Last Glacial Period
In order to understand atmospheric methane (CH4) biogeochemistry now and in the future, we must apprehend its natural variability, without anthropogenic influence. Samples of ancient air trapped within ice cores provide the means to do this. Here we analyze the ultrahigh-resolution CH4 record of the West Antarctic Ice Sheet Divide ice core 67.2â9.8âka and find novel, atmospheric CH4 variability at centennial time scales throughout the record. This signal is characterized by recurrence intervals within a broad 80â500âyear range, but we find that age-scale uncertainties complicate the possible isolation of any periodic frequency. Lower signal amplitudes in the Last Glacial relative to the Holocene may be related to incongruent effects of firn-based signal smoothing processes. Within interstadial and stadial periods, the peak-to-peak signal amplitudes vary in proportion to the underlying millennial-scale oscillations in CH4 concentrationâthe relative amplitude change is constant. We propose that the centennial CH4 signal is related to tropical climate variability that influences predominantly low-latitude wetland CH4 emissions
The DEEP Groth Strip Survey. I. The Sample
The Deep Extragalactic Exploratory Probe (DEEP) is a multi-phase research
program dedicated to the study of the formation and evolution of galaxies and
of large scale structure in the distant Universe. This paper describes the
first five-year phase, denoted DEEP1. A series of ten DEEP1 papers will discuss
a range of scientific topics (e.g., the study of photometric and spectral
properties of a general distant galaxy survey, the evolution observed in galaxy
populations of varied morphologies). The observational basis for these studies
is the Groth Survey Strip field, a 127 square arcminute region which has been
observed with the Hubble Space Telescope in both broad I-band and V-band
optical filters and with the Low Resolution Imaging Spectrograph on the Keck
Telescopes. Catalogs of photometric and structural parameters have been
constructed for 11,547 galaxies and stars at magnitudes brighter than 29, and
spectroscopy has been conducted for a magnitude-color weighted subsample of 818
objects. We evaluate three independent techniques for constructing an imaging
catalog for the field from the HST data, and discuss the depth and sampling of
the resultant catalogs. The selection of the spectroscopic subsample is
discussed, and we describe the multifaceted approach taken to prioritizing
objects of interest for a variety of scientific subprograms. A series of Monte
Carlo simulations then demonstrates that the spectroscopic subsample can be
adequately modeled as a simple function of magnitude and color cuts in the
imaging catalog.Comment: ApJS accepted, 15 pages, 12 figures. Version with higher-quality
figures available at http://astronomy.nmsu.edu/nicol
The compound machinery of government: The case of seconded officials in the European commission
This article explores the compound machinery of government. Attention is directed toward decision making within the core executive of the European Union - the European Commission. The article studies seconded national civil servants (SNEs) hired on short-term contracts. The analysis benefits from an original and rich body of surveys and interview data derived from current and former SNEs. The decision-making dynamics of SNEs are shown to contain a compound mix of departmental, epistemic, and supranational dynamics. This study clearly demonstrates that the socializing power of the Commission is conditional and only partly sustained when SNEs exit the Commission. Any long-lasting effect of socialization within European Union's executive machinery of government is largely absent. The compound decision-making dynamics of SNEs are explained by (1) the organizational affiliations of SNEs, (2) the formal organization of the Commission apparatus, and (3) only partly by processes of resocialization of SNEs within the Commission
Recommended from our members
An analysis of the food system landscape and agricultural value chains for nutrition: A case study from Sierra Leone
The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations (FAO) or of the World Health Organization (WHO) concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Dotted lines on maps represent approximate border lines for which there may not yet be full agreement. The mention of specific companies or products of manufacturers, whether or not these have been patented, does not imply that these are or have been endorsed or recommended by FAO or WHO in preference to others of a similar nature that are not mentioned. Errors and omissions excepted, the names of proprietary products are distinguished by initial capital letters. All reasonable precautions have been taken by FAO and WHO to verify the information contained in this publication. However, the published material is being distributed without warranty of any kind, either expressed or implied. The responsibility for the interpretation and use of the material lies with the reader. In no event shall FAO and WHO be liable for damages arising from its use
Recommended from our members
An Analysis of the Food System Landscape and Agricultural Value Chains for Nutrition: A Case Study from Sierra Leone
This paper summarizes a qualitative case study conducted in Sierra Leone to explore the programmatic challenges of linking nutrition and agriculture nationally through a food system landscape analysis, and the implementation of nutrition-sensitive value chains of two commodities â rice and vegetables. The research undertaken in this project aimed to understand the role markets and value chains play in improving dietary diversification both directly, through an increase in the production of nutritious foods sourced from smallholders in Sierra Leone, and indirectly, through an increase in income for smallholder farmers. Much of the analyses done in this study examined the supply side of the value chain. The study highlights the importance in engaging women in value chains, and their potential role as âchange agentsâ to ensure that nutrition is better integrated along the value chains as producers and consumers (IFPRI/ILRI, 2010).
The study also identified various pathways through which rice and vegetables production, processing and marketing could contribute to improving nutritional status and health. Agriculture and health actors would benefit from jointly developing nutrition indicators to insert into the value chain that address both nutrition and agriculture. While a single intervention targeting only one component of the value chain is likely to have a limited impact, addressing all the identified issues, with several interventions at different levels of the chain can make a real difference
Comparison of serological assays for the detection of SARS-CoV-2 antibodies
SARS-CoV-2 virus was first detected in late 2019 and circulated globally, causing COVID-19, which is characterised by sub-clinical to severe disease in humans. Here, we investigate the serological antibody responses to SARS-CoV-2 infection during acute and convalescent infection using a cohort of (i) COVID-19 patients admitted to hospital, (ii) healthy individuals who had experienced âCOVID19 like-illnessâ, and (iii) a cohort of healthy individuals prior to the emergence of SARS-CoV-2. We compare SARS-CoV-2 specific antibody detection rates from four different serological methods, virus neutralisation test (VNT), ID ScreenÂź SARS-CoV-2-N IgG ELISA, Whole Antigen ELISA, and lentivirus-based SARS-CoV-2 pseudotype virus neutralisation tests (pVNT). All methods were able to detect prior infection with COVID-19, albeit with different relative sensitivities. The VNT and SARSCoV-2-N ELISA methods showed a strong correlation yet provided increased detection rates when used in combination. A pVNT correlated strongly with SARS-CoV-2 VNT and was able to effectively discriminate SARS-CoV-2 antibody positive and negative serum with the same efficiency as the VNT. Moreover, the pVNT was performed with the same level of discrimination across multiple separate institutions. Therefore, the pVNT is a sensitive, specific, and reproducible lower biosafety level alternative to VNT for detecting SARS-CoV-2 antibodies for diagnostic and research applications. Our data illustrate the potential utility of applying VNT or pVNT and ELISA antibody tests in parallel to enhance the sensitivity of exposure to infection
Old English macian, Its Origin and Dissemination
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66612/2/10.1177_007542428601900105.pd
- âŠ