University of Portsmouth

About: University of Portsmouth is a education organization based out in Portsmouth, Portsmouth, United Kingdom. It is known for research contribution in the topics: Population & Galaxy. The organization has 5452 authors who have published 14256 publications receiving 424346 citations. The organization is also known as: Portsmouth and Gosport School of Science and Art & Portsmouth and Gosport School of Science and the Arts.

IL-12 Is a Heparin-Binding Cytokine

Abstract: Using an ELISA approach, we demonstrate that recombinant human IL-12 (rhIL-12) binds strongly to an immobilized heparin-BSA complex. This binding is completely displaceable with soluble heparin, IC50 approximately 0.1 microg/ml, corresponding to approximately 10 nM. By interpolation with our previous findings, this indicates an affinity for heparin greater than that of antithrombin III and comparable with that of FGF-2, two high-affinity heparin-binding proteins. Recombinant murine IL-12 also binds strongly to heparin. The binding of rhIL-12 to heparin shows specificity because chondroitin sulfates A and C fail to compete, whereas chondroitin B inhibits weakly. A highly sulfated heparan sulfate is a strong competitor, whereas other heparan sulfates show weak or no activity. Small heparin fragments inhibit binding, although activity decreases with size. An octasaccharide pool derived by cleavage of heparin with nitrous acid is a significantly stronger inhibitor than its heparinase I-derived counterpart, further indicating structural specificity in the interaction between rhIL-12 and heparin. The binding of recombinant p40 to heparin appears indistinguishable from that of the IL-12 heterodimer, implying that the heparin binding site is largely if not solely located in this subunit. These results show for the first time that IL-12 is a heparin-binding cytokine, a property common to the other Th1-response-inducing cytokines, IFN-gamma and IL-2. Our findings strongly suggest that IL-12 will tend to be retained close to its sites of secretion in the tissues by binding to heparin-like glycosaminoglycans, thus favoring a paracrine role for IL-12.

Galaxy And Mass Assembly: evolution of the Hα luminosity function and star formation rate density up to z < 0.35

Abstract: Measurements of the low-z H alpha luminosity function, Phi, have a large dispersion in the local number density of sources (similar to 0.5-1 Mpc(-3) dex(-1)), and correspondingly in the star formation rate density (SFRD). The possible causes for these discrepancies include limited volume sampling, biases arising from survey sample selection, different methods of correcting for dust obscuration and active galactic nucleus contamination. The Galaxy And Mass Assembly (GAMA) survey and Sloan Digital Sky Survey (SDSS) provide deep spectroscopic observations over a wide sky area enabling detection of a large sample of star-forming galaxies spanning 0.001 < SFRH alpha (M-circle dot yr(- 1)) < 100 with which to robustly measure the evolution of the SFRD in the low-z Universe. The large number of high-SFR galaxies present in our sample allow an improved measurement of the bright end of the luminosity function, indicating that the decrease in Phi at bright luminosities is best described by a Saunders functional form rather than the traditional Schechter function. This result is consistent with other published luminosity functions in the far-infrared and radio. For GAMA and SDSS, we find the r-band apparent magnitude limit, combined with the subsequent requirement for H alpha detection leads to an incompleteness due to missing bright H alpha sources with faint r-band magnitudes.

Frictions in the interbank market and uncertain liquidity needs: Implications for monetary policy implementation

Abstract: This paper shows that depending on the distribution of banks' uncertain liquidity needs and on how monetary policy is implemented, frictions in the interbank market may reinforce the effectiveness of monetary policy. These frictions imply that with its lending and deposit facilities the central bank has an additional effective instrument at hand to impose an impact on bank loan supply. While lowering the rate on the lending facility has, taken for itself, an expansionary effect, lowering the rate on the deposit facility has a contractionary effect. This result has interesting implications for monetary policy implementation at the zero lower bound.

Teaching Three Year-Olds to Pass False Belief Tests: A Conversational Approach

Abstract: A training procedure was developed for teaching three year-old children to pass a standard false belief task. A series of 4 video sequences was developed, in each of which a child showed surprise following the unexpected transfer of an object. A group of 23 three year-olds who failed a standard false belief task took part in 8 discussions of the 4 video clips, over a period of two weeks, and were compared with a control group of 23 task-failers who had 8 story reading sessions over the same time period. The training involved (a) interactive recall of the initial events in each sequence, (b) factual questioning about the events and (c) an explanation of the thoughts and actions of the video protagonists. The emphasis was on positive elaboration of children's answers rather than on negative feedback as counter evidence. The training group performed significantly better at an immediate post-test, and at a follow-up test two weeks later, on a similar as well as a generalisation task. Task success was unrelated to vocabulary (BPVS) score, but was significantly related to success of responses during the training. The results indicate learning in the Training group of a discursive format for talking about events useful for describing false beliefs.

Financial and monetary policy responses to oil price shocks: evidence from oil-importing and oil-exporting countries

Abstract: In this study, we investigate the financial and monetary policy responses to oil price shocks using a Structural VAR framework. We distinguish between net oil-importing and net oil-exporting countries. Since the 80s, a significant number of empirical studies have been published investigating the effect of oil prices on macroeconomic and financial variables. Most of these studies though, do not make a distinction between oil-importing and oil-exporting economies. Overall, our results indicate that the level of inflation in both net oil-exporting and net oil-importing countries is significantly affected by oil price innovations. Furthermore, we find that the response of interest rates to an oil price shock depends heavily on the monetary policy regime of each country. Finally, stock markets operating in net oil-importing countries exhibit a negative response to increased oil prices. The reverse is true for the stock market of the net oil-exporting countries. We find evidence that the magnitude of stock market responses to oil price shocks is higher for the newly established and/or less liquid stock markets.