The SCUBA Local Universe Galaxy Survey

The SCUBA local universe galaxy survey is the first systematic survey of the local universe at submillimetre wavelengths. We have observed ~200 galaxies from the IRAS bright galaxy catalogue and the CfA optical redshift survey. The IRAS sample showed that our estimate of the luminosity function was potentially biased if a cold population of galaxies existed which would not have appeared in the IRAS BGS but would have been detected in a SCUBA blind survey. Here we present preliminary results from the optically selected sample which suggest that this is indeed the case.Comment: 2 pages, 2 figs, proceedings from Euro-conference on galaxy evolution held in La Reunion, 200

The role of p38 MAPK and its substrates in neuronal plasticity and neurodegenerative disease

A significant amount of evidence suggests that the p38-mitogen-activated protein kinase (MAPK) signalling cascade plays a crucial role in synaptic plasticity and in neurodegenerative diseases. In this review we will discuss the cellular localisation and activation of p38 MAPK and the recent advances on the molecular and cellular mechanisms of its substrates: MAPKAPK 2 (MK2) and tau protein. In particular we will focus our attention on the understanding of the p38 MAPK-MK2 and p38 MAPK-tau activation axis in controlling neuroinflammation, actin remodelling and tau hyperphosphorylation, processes that are thought to be involved in normal ageing as well as in neurodegenerative diseases. We will also give some insight into how elucidating the precise role of p38 MAPK-MK2 and p38 MAPK-tau signalling cascades may help to identify novel therapeutic targets to slow down the symptoms observed in neurodegenerative diseases such as Alzheimer's and Parkinson's disease

Candidate High Redshift and Primeval Galaxies in Hubble Deep Field South

We present the results of colour selection of candidate high redshift galaxies in Hubble Deep Field South (HDF-S) using the Lyman dropout scheme. The HDF-S data we discuss were taken in a number of different filters extending from the near--UV (F300W) to the infrared (F222M) in two different fields. This allows us to select candidates with redshifts from z~3 to z~12. We find 15 candidate z~3 objects (F300W dropouts), 1 candidate z~4 object (F450W dropout) and 16 candidate z$\sim$5 objects (F606W dropouts) in the ~ 4.7 arcmin^2 WFPC-2 field, 4 candidate z~6 (optical dropouts) and 1 candidate z~8 (F110W dropout) in the 0.84 arcmin^2 NICMOS-3 field. No F160W dropouts are found (z~12). We compare our selection technique with existing data for HDF-North and discuss alternative interpretations of the objects. We conclude that there are a number of lower redshift interlopers in the selections, including one previously identified object (Treu et al. 1998), and reject those objects most likely to be foreground contaminants. Even after this we conclude that the F606W dropout list is likely to still contain substantial foreground contamination. The lack of candidate very high redshift UV-luminous galaxies supports earlier conclusions by Lanzetta et al. (1998). We discuss the morphologies and luminosity functions of the high redshift objects, and their cosmological implications.Comment: Accepted for publication in MNRA

TRADE POLICY UNDER IMPERFECT COMPETITION: AN ASSESSMENT OF THE TRQ ON LAMB MEAT

The United States imposed a tariff-rate quota (TRQ) on lamb meat in July 1999. Early analysis suggested the possibility that lamb growers could lose welfare via the creation of packer market power. This paper considers how subsequent events modify that analysis. Observed prices suggest reduced pass-through. Lamb prices are unchanged and more stable. Using an annual quota instead of a quarterly quota reduces the opportunity for market conduct switching. Early termination of the TRQ to comply with the WTO rulings magnifies any welfare loss. Assistance payments prevent welfare losses to growers with little impact on the market.International Relations/Trade, Livestock Production/Industries,

The Submillimetre Properties of Ultraluminous Infrared Galaxies

We present the results of SCUBA observations of a complete sample of local ULIRGs. Twenty of the initial sample of 23 sources are detected at 850 um and nearly half of the objects are also detected at 450 um. This data is combined with existing observations of a further seven ULIRGs to produce the largest sample of submm observations of ULIRGs currently available. We use similar techniques to the SLUGS survey to fit dust spectral energy distributions (SEDs) to their far-IR emission. We find that ULIRGs have a higher dust temperature than lower luminosity objects (42K compared to 35K) and a steeper emissivity index. For those objects where 450 um fluxes are available we also attempt a two component dust SED fit, with warm and cool dust and a dust emissivity index of beta=2. Such a model has been found to be a good fit to lower luminosity systems. We find that it also works well for ULIRGs, but that ULIRGs have a smaller cold dust component. Comparison of the dust mass derived for ULIRGs and more normal spiral galaxies suggests that the dust content of a ULIRG is simply the combined dust content of the two galaxies whose merger has triggered the ULIRG activity. We examine the high end of the 850 um luminosity function and find results consistent with those of the earlier SLUGS survey. We also find that ULIRGs make up only about 50% of the high end of the 850 um luminosity function, with LIRGs containing a large mass of cool dust likely to be responsible for the rest.Comment: Accepted for publication in MNRA

The SCUBA Local Universe Galaxy Survey I: First Measurements of the Submillimetre Luminosity and Dust Mass Functions

We have used SCUBA to observe a complete sample of 104 galaxies selected at 60 microns from the IRAS BGS and we present here the 850 micron measurements. Fitting the 60,100 and 850 micron fluxes with a single temperature dust model gives the sample mean temperature T=36 K and beta = 1.3. We do not rule out the possibility of dust which is colder than this, if a 20 K component was present then our dust masses would increase by factor 1.5-3. We present the first measurements of the luminosity and dust mass functions, which were well fitted by Schechter functions (unlike those 60 microns). We have correlated many global galaxy properties with the submillimetre and find that there is a tendancy for less optically luminous galaxies to contain warmer dust and have greater star formation efficiencies (cf. Young 1999). The average gas-to-dust ratio for the sample is 581 +/- 43 (using both atomic and molecular hydrogen), significantly higher than the Galactic value of 160. We believe this discrepancy is due to a cold dust component at T < 20 K. There is a suprisingly tight correlation between dust mass and the mass of molecular hydrogen as estimated from CO measurements, with an intrinsic scatter of ~50%.Comment: 24 pages, 15 figures, 8 tables, accepted for publication in MNRA

Mapping the interstellar medium in galaxies with Herschel/SPIRE

The standard method of mapping the interstellar medium in a galaxy, by observing the molecular gas in the CO 1-0 line and the atomic gas in the 21-cm line, is largely limited with current telescopes to galaxies in the nearby universe. In this letter, we use SPIRE observations of the galaxies M99 and M100 to explore the alternative approach of mapping the interstellar medium using the continuum emission from the dust. We have compared the methods by measuring the relationship between the star-formation rate and the surface density of gas in the galaxies using both methods. We find the two methods give relationships with a similar dispersion, confirming that observing the continuum emission from the dust is a promising method of mapping the interstellar medium in galaxies

The incorporation of glycine-2-14C into urinary uric acid in normal and porphyric human subjects

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Symptomatic porphyria

A study has been made of 7 alcoholic and 2 non-alcoholic patients with symptomatic porphyria. Siderosis (mild or absent in most cases), focal fatty change and lipofuscin pigmentation were noted on light microscopy while ultrastructural study revealed that focal cellular lysis was unexpectedly common. Unidentified cytoplasmic inclusions (possibly porphyrins) were present in 3 cases. It was concluded that increased synthesis and storage of porphyrins in the liver could lead to some cytoplasmic damage, but that alcoholic excess probably accounts for the majority of the hepatocellular abnormalities.S. Afr. Med. J., 48, 1803 (1974)