The application of the CERIF data format to Snowball metrics

The euroCRIS Indicators Task Group aims to develop and share best practice in the use of indicators to support research information management. One of the outputs of the group will be indicators expressed in CERIF that can re-used by CERIF-compliant software services to support consistent measurements for both national and international purposes. This Task Group will express multiple sets of indicators in CERIF, with Snowball Metrics being the first set to be tackled. The goal of the Snowball Metrics initiative is for research-intensive institutions to share their knowledge and experiences to agree best practice in evidence-based institutional strategic planning. Agreed and tested metrics “recipes”, or methodologies, are shared free of charge with the sector in the Snowball Metrics Recipe Book (www.snowballmetrics.com/metrics)1 for use by any organization, whether for public service or commercial purposes. One of the principles of Snowball Metrics is that they are system-agnostic: in other words, that although particular types of data are needed to support their calculation, the data can come from any relevant source such that the recipes are not tied to any one particular system or supplier of research information. The application of the CERIF data standard to the recipes is an important component in enabling benchmarking between institutions in a system-agnostic manner through the exchange of Snowball Metrics. CERIFication of Snowball Metrics is also expected to facilitate the endorsement of these recipes as global standards. The first set of recipes was agreed and tested by a group of universities in the United Kingdom, but the vision is that Snowball Metrics are supported by universities globally, and that multiple national groups contribute their expertise to agree how best to leverage the institutional and national data sources available, alongside proprietary data sources. The formation of Working Groups and the use of Snowball Metrics outside the United Kingdom demonstrate that the initiative is gaining global traction, and strongly indicate that the needs being addressed are widespread problems for which the sector would like to find a single answer. The universal nature of CERIF provides an important reference point to which it is expected that distinct but equivalent national data sources can be mapped and so used in international benchmarking

Studies on biochemical variants of BHK 21/C13 cells

Polyoma transformed BHK 21/C13 cells and some of their variants wore used during these investigations. The variants had previously been derived from BHK 21/C13 cells by selection for resistance to several purine and pyrimidine analogues in tissue culture. The behaviour of these cells was compered in several ways. The levels of resistance of the cells to some purine and pyrimidine analogues were determined. The variants when exposed to an analogue to which they were resistant continued to grow at more than one hundred times the concentration at which the majority of wild type cells were killed. The variants generally survived no better than the wild type in the presence of those purine and pyrimidine analogues for which resistance had not been selected. The growth curves of the wild typo and the variants under non-restrictive conditions were identical. The incorporation of radioactively labelled purines and pyrimidines from the growth medium was determined using both scintillation counting and autoradiography. Mid type cells incorporated each of the nucleic acid precursors used in large amounts. In most cases the variants were no longer capable of incorporating significant quantities of radioactive bases or nucleosides to whose analogues they were resistant. The phenomenon of metabolic co-operation is well established. It occurs between cells in contact at light microscopic level and causes an alteration in the phenotype of a co-operating variant cell to that of the cell with which it is in contact. Metabolic co-operation requires a donor-recipient relationship between at least two cells, with the cell exhibiting the enzyme activity being the donor. The technique of double label autoradiography was used to distinguish between two types of cell in a mixture after one bad been pre-labelled with 14.0 thymidine. Metabolic co-operation could be studied at the level of the individual cell. The effects of metabolic co-operation were investigated using cells growing under selective conditions. Under conditions in which the cells were autotrophic for a purine source metabolic co-operation influenced the selection. Variants were capable of growing when present as a mixture under conditions in which they would not be able to survive alone. This effect of metabolic co-operation has been termed "the kiss of life". Metabolic co-operation has implications both for the selection of variant cells in culture and also for the diagnosis and possible treatment of inborn errors of metabolism. The biochemical basis of metabolic co-operation was investigated. The phenotypic alteration was found to have a short half life which 10 compatible with there being an exchange of labelled material, possibly nucleotides, between cells. Metabolic co-operation may be suitable as an in vitro model of differentiating systems based on the setting up of concentration gradients of low molecular weight diffusible substances between cells. The reactivation of chicken erythrocyte nueicli was followed after fusion with the DM 21/013/P7Y cell variants. Sendai virus was grown up in embryonated eggs, inactivated within B-propriolactone and used to fuse the cells in suspension. The reactivation process followed the pattern described in other cells, the reactivating nucleus undergoing enlargement, synthesising DNA, MIA, forming a nucleolus and finally directing the synthesis of chick specified proteins. The process of reactivation progressed more rapidly within the hamster cells than the mouse A9 cells used by other workers. A variant selected for resistance to four purine analogues offered the possibility of following the reactivation of four enzyme activities simultaneously within a single type of cell. The time course of the appearance of all four was the came and correlated well with the appearance of a functional nucleolus within the reactivated erythrocyte nucleus

Excitations in confined helium

We design models for helium in matrices like aerogel, Vycor or Geltech from a manifestly microscopic point of view. For that purpose, we calculate the dynamic structure function of 4He on Si substrates and between two Si walls as a function of energy, momentum transfer, and the scattering angle. The angle--averaged results are in good agreement with the neutron scattering data; the remaining differences can be attributed to the simplified model used here for the complex pore structure of the materials. A focus of the present work is the detailed identification of coexisting layer modes and bulk--like excitations, and, in the case of thick films, ripplon excitations. Involving essentially two--dimensional motion of atoms, the layer modes are sensitive to the scattering angle.Comment: Phys. Rev. B (2003, in press

Outflows in Infrared-Luminous Starbursts at z < 0.5. I. Sample, NaI D Spectra, and Profile Fitting

We have conducted a spectroscopic survey of 78 starbursting infrared-luminous galaxies at redshifts up to z = 0.5. We use moderate-resolution spectroscopy of the NaI D interstellar absorption feature to directly probe the neutral phase of outflowing gas in these galaxies. Over half of our sample are ultraluminous infrared galaxies that are classified as starbursts; the rest have infrared luminosities in the range log(L_IR/L_sun) = 10.2 - 12.0. The sample selection, observations, and data reduction are described here. The absorption-line spectra of each galaxy are presented. We also discuss the theory behind absorption-line fitting in the case of a partially-covered, blended absorption doublet observed at moderate-to-high resolution, a topic neglected in the literature. A detailed analysis of these data is presented in a companion paper.Comment: 59 pages, 18 figures in AASTeX preprint style; to appear in September issue of ApJ

Imaging of Ultraluminous Infrared Galaxies in the Near-UV

We present the first ground-based U' (3410 angstroms) images of Ultraluminous Infrared Galaxies (ULIGs). Strong U' emission (median total M_U' = -20.8) is seen in all systems and in some cases the extended tidal features (both the smooth stellar distribution and compact star-forming features) contribute up to 60-80% of the total flux. The star-forming regions in both samples are found to have ages based on spectral synthesis models in the range 10-100 Myrs, and most differences in color between them can be attributed to the effects of dust reddening. Additionally, it is found that star-formation in compact knots in the tidal tails is most prominent in those ULIGs which have double nuclei, suggesting that the star-formation rate in the tails peaks prior to the actual coalescence of the galaxy nuclei and diminishes quickly thereafter. Similar to results at other wavelengths, the observed star formation at U' can only account for a small fraction of the known bolometric luminosity of the ULIGs. Azimuthally averaged radial light profiles at U' are characterized by a sersic law with index n=2, which is intermediate between an exponential disk and an r^(-1/4) law and closely resembles the latter at large radii. The implications of this near-ultraviolet imaging for optical/near-infrared observations of high redshift counterparts of ULIGs are discussed.Comment: 30 pages, 4 tables, and 9 figures, 2 of which are JPEGs. To appear in the August, 2000 edition of the Astronomical Journa

Redshift clustering in the Hubble Deep Field

We present initial results from a redshift survey carried out with the Low Resolution Imaging Spectrograph on the 10~m W. M. Keck Telescope in the Hubble Deep Field. In the redshift distribution of the 140 extragalactic objects in this sample we find 6 strong peaks, with velocity dispersions of ${\sim}400${\kms}. The areal density of objects within a particular peak, while it may be non-uniform, does not show evidence for strong central concentration. These peaks have characteristics (velocity dispersions, density enhancements, spacing, and spatial extent) similar to those seen in a comparable redshift survey in a different high galactic latitude field (Cohen et al 1996), confirming that the structures are generic. They are probably the high redshift counterparts of huge galaxy structures (``walls'') observed locally.Comment: 14 pages, including 2 figures, to appear in ApJ Letter

Quantum sticking, scattering and transmission of 4He atoms from superfluid 4He surfaces

We develop a microscopic theory of the scattering, transmission, and sticking of 4He atoms impinging on a superfluid 4He slab at near normal incidence, and inelastic neutron scattering from the slab. The theory includes coupling between different modes and allows for inelastic processes. We find a number of essential aspects that must be observed in a physically meaningful and reliable theory of atom transmission and scattering; all are connected with multiparticle scattering, particularly the possibility of energy loss. These processes are (a) the coupling to low-lying (surface) excitations (ripplons/third sound) which is manifested in a finite imaginary part of the self energy, and (b) the reduction of the strength of the excitation in the maxon/roton region