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The Ordovician peri-Laurentian Grangegeeth Terrane in eastern Ireland and the adjacent Katian to Wenlock Rathkenny Tract are together a relict of the closing Iapetus Ocean. The Rathkenny Tract succession is part of the Laurentian Southern Uplands-Down-Longford Terrane accretionary prism, but the contact between the Rathkenny and Grangegeeth terranes is cryptic. Two cores of Lower Paleozoic strata along a buried projection of the Rathkenny-Grangegeeth outcrops contain volcaniclastic units within a succession of mudstone and siltstone. Laser ablation inductively coupled plasma mass spectrometry U-Pb dating of zircons from volcanogenic horizons yielded a maximum depositional age of c. 450 Ma. Nearly 98% of the zircon ages are 480-445 Ma, indicating a proximal volcanic source. The trace element geochemistry of the Ordovician zircons indicates a host magma sourced from continental crust. A diverse ostracod fauna in the mudstones suggests a Katian age and includes species with Baltic, Laurentian and Avalonian affinities. We propose a paired subduction zone model for the emplacement of the Grangegeeth-Rathkenny succession, with the Rathkenny strata deposited on an oceanic plate between the Laurentian margin accretionary prism and the 480-450 Ma Grangegeeth peri-Laurentian microcontinental arc. Volcaniclastic detritus fed into the Rathkenny basin was then incorporated into the accretionary prism. The mixed fauna indicates that the Iapetus Ocean was narrow by Katian time. [ABSTRACT FROM AUTHOR]

To investigate the mode of action of the p16(INK4a) tumor suppressor protein, we have established U2-OS cells in which the expression of p16(INK4a) can be regulated by addition or removal of isopropyl-beta-D-thiogalactopyranoside. As expected, induction of p16(INK4a) results in a G1 cell cycle arrest by inhibiting phosphorylation of the retinoblastoma protein (pRb) by the cyclin-dependent kinases CDK4 and CDK6. However, induction of p16(INK4a) also causes marked inhibition of CDK2 activity. In the case of cyclin E-CDK2, this is brought about by reassortment of cyclin, CDK, and CDK-inhibitor complexes, particularly those involving p27(KIP1). Size fractionation of the cellular lysates reveals that a substantial proportion of CDK4 participates in active kinase complexes of around 200 kDa. Upon induction of p16(INK4a), this complex is partly dissociated, and the majority of CDK4 is found in lower-molecular-weight fractions consistent with the formation of a binary complex with p16(INK4a). Sequestration of CDK4 by p16(INK4a) allows cyclin D1 to associate increasingly with CDK2, without affecting its interactions with the CIP/KIP inhibitors. Thus, upon the induction of p16(INK4a), p27(KIP1) appears to switch its allegiance from CDK4 to CDK2, and the accompanying reassortment of components leads to the inhibition of cyclin E-CDK2 by p27(KIP1) and p21(CIP1). Significantly, p16(INK4a) itself does not appear to form higher-order complexes, and the overwhelming majority remains either free or forms binary associations with CDK4 and CDK6.

Two nonspecific immunological assays were combined with radionuclide scanning to monitor 113 patients thrice weekly following allotransplantation. The nonspecific immune assays included measurement of the percentage of active T rosette-forming cells ( A-T RFCs) and spontaneous blastogenesis (SB). An increase in SB and decrease in A-T RFCs (greater than 1SD of normal controls) constituted an immune event. The immune parameters were correlated with thrice weekly radionuclide studies which were computer analyzed for glomer-ular and tubular function. Alteration of the immunological and radionuclide parameters significantly correlated (P < 0.001) with 90 rejection episodes displayed by 72 nonantithymocyte globulin (ATG)-treated renal allograft recipients during the first 30 postoperative days. In the absence of clinically defined rejection, changes in immune parameters correlated with (1) decline of radionuclide parameters and (2) alterations in weight, temperature, creatinine clearance, and serum creatinine, suggesting subclinical events. As a result of the effects of ATG on lymphocytes, a similar comparison could not be made for 41 other patients treated with this immunosuppressive drug. The incidence of false positive tests was 12.7. Thus, the combination of two nonspecific immune parameters, A-T RFCs and SB, with computerized analysis of radionuclide scans may afford a reliable index to diagnose early rejection or impaired function of renal allografts.

This study investigated the foraging behaviour, diving behaviour, movements and diet of lactating southern sea lions in the Falkland Islands. They appeared to be primarily nocturnal, benthic foragers hunting at depths ranging from the surf line down to 250 m, and from just off their breeding sites out to 45 km offshore. Occasional longer trips may extend foraging ranges to over 150 km from breeding sites. Attendance patterns suggest that Falklands' sea lions do not haulout simply to feed their pups. Other factors such as predation and thermoregulation may cause them to come ashore. When at sea they travelled at approximately 1 m s−1, slower than previous studies of otariids indicated. Absence from the breeding site did not imply continuous foraging; all study animals used remote haulout sites away from their pups. Repeated use of the same areas and the short duration of foraging trips suggest that they were able to catch enough food within a fairly small foraging range. Data on diet support the suggestion that lactating sea lions are mainly benthic foragers. They take a wide range of prey species. The most common cephalopods were Loligo gahi, similar in size to those taken by the fishery. There is therefore potential for competition between the sea lion population and the Loligo trawl fishery. There was considerable overlap between the diet of sea lions and those of Gentoo and Magellanic penguins, which suggests that sea lions may compete with both species.

Abstract: Niska is a white-skinned, white-fleshed potato cultivar with a maincrop maturity, stable yield and chipping quality and good storage characteristics. It has considerable resistance to Common scab, Early blight, PLRV, PVY and PVS. Evaluation conducted by chip processors in Alberta and Ontario, under commercial conditions, indicates that the cultivar has good storage characteristics.

A new thermally stable organic resin is described. Results are presented for the development of polybenzimidazole (PBI) resin-bonded solid-film lubricants. These solid-film lubricants are composed of molybdenum disulfide, antimony trioxide, and the PBI resins. Steps followed for mixing, applying, and curing these films are presented. The test equipment and procedures used to test the film formulations are described. Wear-life comparisons to conventional commercially available resin-bonded films qualified under MIL-L-8937 are presented.

Results are presented for the bonding of thin, sintered, fluoride films of BaF2 and CaF2 with mono-aluminum phosphate. Friction and wear behavior of these films has been defined in terms of film compositional changes, film curing procedures, and substrate variations when subjected to varying levels of temperature and load. Mono-aluminum phosphate was found to greatly enhance the adhesion of the sintered fluoride film. There was a strong dependence of wear life at 1000 deg F on the mono-aluminum phosphate content of the film. Films containing 6 vol. percent phosphate appear to be near optimum and exhibited wear lives of 1,000,000 load cycles under sliding conditions in a dual rub-shoe device with friction coefficient levels in the order of 0.10 to 0.20. Near-optimum values were determined for cure temperature (950 deg C), and surface finish (23 μ in. rms) on rhodium-plated substrates. Graphite and gold were added to the aluminum phosphate bonded BaF2: CaF2 films. Both additives were found to lower the friction coefficient at room temperature.

A sub-adult grey seal was caught and tagged with a satellite relay data logger at Tihällan (61°28'00?N, 17°25'40?E), Sweden, on 21 August 1992. We tracked it for 115 days during which time we recorded 841 locations, data on 3556 dives and 80 “haulout” periods. It travelled 730 km in the first 12 days to the southern Archipelago Sea. It stayed most of the remaining time within 25 km of a haulout site, with a major exception of an 8-day trip of 520 km. Dive shape and swimming activity were used to distinguish dive types. Square-shaped “foraging” dives were more common over the midday period. “Haulout” periods were more common during the night.