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Byline: R. J. Dawson (1), M. E. Dickson (2), R. J. Nicholls (3), J. W. Hall (1), M. J. A. Walkden (1), P. K. Stansby (4), M. Mokrech (3), J. Richards (5), J. Zhou (6), J. Milligan (7), A. Jordan (7), S. Pearson (8), J. Rees (9), P. D. Bates (10), S. Koukoulas (11), A. R. Watkinson (7) Abstract: The risks to human populations in coastal areas are changing due to climate and socio-economic changes, and these trends are predicted to accelerate during the twenty-first century. To understand these changing risks, and the resulting choices and pathways to successful management and adaptation, broad-scale integrated assessment is essential. Due to their complexity the two risks of flooding and erosion are usually managed independently, yet frequently they are interconnected by longshore exchange of sediments and the resulting broad scale morphological system behaviour. In order to generate new insights into the effects of climate change and coastal management practises on coastal erosion and flood risk, we present an integrated assessment of 72 km of shoreline over the twenty-first century on the East Anglian coast of England which is a site of significant controversy about how to manage coastal flood and erosion risks over the twenty-first century. A coupled system of hydrodynamic, morphological, reliability and socio-economic models has been developed for the analysis, implemented under scenarios of coastal management, climate and socio-economic change. The study is unique in coastal management terms because of the large spatial scale and extended temporal scale over which the analysis is quantified. This study for the first time quantifies what has for some years been argued qualitatively: the role of sediments released from cliff erosion in protecting neighbouring low-lying land from flooding. The losses and benefits are expressed using the common currency of economic risk. The analysis demonstrates that over the twenty-first century, flood risk in the study area is expected to be an order of magnitude greater than erosion risk. Climate and socio-economic change and coastal management policy have a significant influence on flood risk. This study demonstrates that the choices concerning coastal management are profound, and there are clear tradeoffs between erosion and flood impacts. Author Affiliation: (1) Tyndall Centre for Climate Change Research, School of Civil Engineering and Geosciences, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK (2) School of Geography, Geology and Environmental Science, The University of Auckland, Private Bag 92019, Auckland, New Zealand (3) Tyndall Centre for Climate Change Research, School of Civil Engineering and the Environment, Southampton University, Highfield, Southampton, SO17 1BJ, UK (4) Tyndall Centre for Climate Change Research, School of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester, M60 1QD, UK (5) ABP Marine Environmental Research, Waterside House, Town Quay, Southampton, S014 2AQ, UK (6) Department of Civil Engineering, University of Liverpool, Brownlow Hill, Liverpool, L69 3GH, UK (7) Tyndall Centre for Climate Change Research, School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK (8) British Geological Survey, Keyworth, Nottingham, NG12 5GG, UK (9) Natural Environment Research Council, Polaris House, North Star Avenue, Swindon, SN2 1EU, UK (10) School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS, UK (11) Geography Department, University of the Aegean, University Hill, Mytilene, 81100, Greece Article History: Registration Date: 12/11/2008 Received Date: 01/10/2007 Accepted Date: 28/10/2008 Online Date: 30/01/2009

Abstract: We imposed a sustained reduction in glucose supply to late-gestation fetal sheep to see whether the reduction in glucose and insulin levels affected renal growth, renin expression and synthesis, [...]

A novel algorithm based on subspace projections is developed for blindly estimating the discrete orders of a linear finite-impulse-response (FIR) multiple-input multiple-output (MIMO) system, the number of subsystems that attain each other and the total number of inputs. Simulations in the context of blind channel order estimation show good performance in comparison to existing schemes developed for single-input multiple-output (SIMO) systems.

These experiments examined whether renal growth and the fetal renin-angiotensin system could be stimulated by infusion of amino acids and whether chronic amino acid infusions restored glomerulotubular balance, which had been disrupted during 4-h infusions. Five fetal sheep aged 122 [+ or -] 1 days gestation received an infusion of alanine, glycine, proline and serine in 0.15 M saline at 0.22 mmol/min for 7 days. Six control fetuses were given saline at the same rate (5 ml/h). Kidney wet weights after amino acid infusion were 28% larger than control fetuses (P < 0.05), and renal angiotensinogen mRNA levels were -2.6-fold higher (P < 0.005). Circulating renin levels and renal renin mRNA levels were suppressed (P < 0.05), and renal renin protein levels tended to be lower. Arterial pressure was increased, and there was a marked, sustained natriuresis and diuresis. Glomerular filtration rate and filtered sodium were ~two-fold higher throughout infusion (P < 0.05). Fractional proximal sodium reabsorption, suppressed at 4 h (from 73.4 [+ or -] 6.5 to 53.7 [+ or -] 10.2%), did not return to control levels (36.1 [+ or -] 3.4% on day 7, P < 0.05). Distal sodium reabsorption was markedly increased (from 79 [+ or -] 25 to 261 [+ or -] 75 [micro]mol/min by day 7, P < 0.005), but this was not sufficient to restore glomerulotubular balance. The resultant high rates of sodium excretion led to hyponatremia and polyhydramnios. In conclusion, longterm amino acid infusions increased renal angiotensinogen gene expression, kidney weight, and distal nephron sodium reabsorptive capacity but failed to restore proximal and total glomerulotubular balance. fetus; renal function

Blind identification of a class of bilinear systems, excited by non-Gaussian higher order white noise, is examined and discussed.

In sheep, placental size is maximal by midgestation, but blood flow continues to increase until term. No nerves are present and ANG II is thought to be a major regulator of vascular tone. We hypothesized that angiotensin type 2 receptors (A[T.sub.2]) would predominate over type 1 (A[T.sub.1]) until late in gestation and be primarily expressed in the vasculature. Real-time PCR, hybridization histochemistry, and ligand-binding studies were performed on placentae and fetal membranes at 27, 45, 66 [+ or -] 1, 100 [+ or -] 4, 130, and 140 days of gestation (term [approximately equal to] 150 days) to determine quantitative changes and localization. The maximum level of A[T.sub.1] expression occurred in the 45-day placenta and was located predominantly in the maternal stromal cells. A[T.sub.1] receptors were expressed in the endothelial cells of the chorion in the first half of pregnancy, where later in gestation, both A[T.sub.1] and A[T.sub.2] receptors were predominant in blood vessels. These results suggest that ANG II, via the A[T.sub.1] receptor, may have hitherto unsuspected important roles in the growth/function on the ovine placenta during the maximal growth phase. A[T.sub.1] receptor; A[T.sub.2] receptor; placenta; pregnancy; real-time polymerase chain reaction

Identification of a discrete input-output bilinear system driven by an independent identically distributed (iid) stochastic input and corrupted by measurement noise is discussed. An algorithmic procedure for direct computation of unknown model parameters is proposed, based on crosscumulant information up to third order.

Second-order Volterra systems identification is examined in the context of Fredholm integral equations.

This article examines the reasons behind the Australian currency devaluation in 1999-2000. Topics addressed include falling commodity prices, foreign debt, the exchange rate, economic policy, and the value of the Australian dollar against the US dollar.

Two distinct cellobiose dehydrogenases (CDH) isolated from the white rot fungus Trametes versicolor have molecular weights of 97 kDa and 81 kDa and isoelectric points of 4.2 and 6.4 respectively. The larger CDH (CDH 4.2) contains both flavin and heme as cofactors and the smaller CDH (CDH 6.4) contains only flavin. Both the CDH isoforms are specific for the beta-1,4 glycosidic bond and oxidize cellobiose as their preferred substrate, though cellotriose and lactose are also used. CDH 6.4 has a higher K(sub m) and a lower V(sub max) and turnover number than CDH 4.2, for all substrates.

General nonlinear input-output systems having Volterra expansions and inspired by stationary, zero mean Gaussian inputs with arbitrary spectra are identified. Time and frequency domain formulae are found for the kernels, using crosscumulant information. The time and frequency domain formulae's optimality in mean squared error is established.

Moritz, Karen, Irene Koukoulas, Anthony Albiston, and E. Marelyn Wintour. Angiotensin II infusion to the midgestation ovine fetus: effects on the fetal kidney. Am J Physiol Regulatory Integrative Comp Physiol 279: R1290-R1297, 2000.--Renal and cardiovascular responses to an intravenous infusion of ANG II (1 [micro]g/h) or saline for 3 days were examined in ovine fetuses at midgestation (75-85 days of gestation, term 150 days). ANG II caused an increase in fetal blood pressure (36 [+ or -] 2 to 44 [+ or -] 3 mmHg) and urine flow rate (8 [+ or -] 2 to a maximum of 18 [+ or -[ 6 ml/h). Plasma renin concentrations decreased in ANG II-infused fetuses. Fetal fluids (amniotic and allantoic) did not differ in volume or composition between the groups when measured at postmortem. There was no difference in the expression levels of the mRNA for the angiotensin ([AT.sub.1] or [AT.sub.2]) receptors between the two groups when measured by an RNase protection assay. However, there was a significant decline in renin and [AT.sub.1] receptor gene expression when measured by a real-time polymerase chain reaction method. These results indicate that ANG II is diuretic and pressor when infused at midgesration. ANG II can feedback to decrease renin secretion by the fetal kidney, and this may occur by decreased renin gene expression. angiotensin receptors; renin; blood pressure