Modelling the cycling of persistent organic pollutants (POPs) in the North Sea system: Fluxes, loading, seasonality, trends

The fate and cycling of two selected POPs is investigated for the North Sea system with an improved version of a fate and transport ocean model (FANTOM). The model uses atmospheric data from the EMEP MSC East POP model (Gusev et al., 2009), giving reasonable concentrations and seasonal distributions for the entire region, as opposed to the three observation stations that Ilyina et al. (2006) were limited to. Other model improvements include changes in the calculation of POP exchange between the water column and sediment.

We chose to simulate the fate of two POPs with very different properties, ?-HCH and PCB 153. Since the fate and cycling of POPs are strongly affected by hydrodynamic processes, a high resolution version of the Hamburg Shelf Ocean Model (HAMSOM) was developed and utilised. Simulations were made for the period 1996–2005. Both models were validated by comparing results with available data, which showed that the simulations were of very satisfactory quality.

Model results show that the North Sea is a net sink for ?-HCH and a net source to the atmosphere of PCB 153. Total masses of ?-HCH and PCB 153 in 2005 are reduced to 30% and 50%, respectively, of 1996 values.

Storms resuspending bottom sediments into the water column mobilise POPs into the atmosphere and have the potential to deliver substantial loads of these POPs into Europe.

Electron refluxing and K-shell line emission from Ti foils irradiated with sub-picosecond laser pulses at 527nm

We present data on emission of K-shell radiation from Ti foils irradiated with subpicosecond pulses of second harmonic radiation (527 nm) from the TARANIS laser system at intensities of up to 1018 Wcm-2. The data are used to demonstrate that a resonance absorption type mechanism is responsible for absorption of the laser light and to estimate fast electron temperatures of 30–60 keV that are in broad agreement with expectation from models of absorption for a steep density gradient. Data taken with resin-backed targets are used to demonstrate clear evidence of electron refluxing even at the modest fast electron temperatures inferred.

On Quillen's calculation of graded K-theory

We adapt Quillen’s calculation of graded K-groups of Z-graded rings with support in N to graded K-theory, allowing gradings in a product Z×G with G an arbitrary group. This in turn allows us to use induction and calculate graded K-theory of Z -multigraded rings.

Functional expression of KCNQ (Kv7) channels in guinea-pig bladder smooth muscle and their contribution to spontaneous activity

Background and Purpose: The aim of the study was to determine whether KCNQ channels are functionally expressed in bladder smooth muscle cells (SMC) and to investigate their physiological significance in bladder contractility. 

Experimental Approach: KCNQ channels were examined at the genetic, protein, cellular and tissue level in guinea pig bladder smooth muscle using RT-PCR, immunofluorescence, patch-clamp electrophysiology, calcium imaging, detrusor strip myography, and a panel of KCNQ activators and inhibitors. 

Key Results: KCNQ subtypes 1-5 are expressed in bladder detrusor smooth muscle. Detrusor strips typically displayed TTX-insensitive myogenic spontaneous contractions that were increased in amplitude by the KCNQ channel inhibitors XE991, linopirdine or chromanol 293B. Contractility was inhibited by the KCNQ channel activators flupirtine or meclofenamic acid (MFA). The frequency of Ca2+-oscillations in SMC contained within bladder tissue sheets was increased by XE991. Outward currents in dispersed bladder SMC, recorded under conditions where BK and KATP currents were minimal, were significantly reduced by XE991, linopirdine, or chromanol, and enhanced by flupirtine or MFA. XE991 depolarized the cell membrane and could evoke transient depolarizations in quiescent cells. Flupirtine (20M) hyperpolarized the cell membrane with a simultaneous cessation of any spontaneous electrical activity. 

Conclusions and Implications: These novel findings reveal the role of KCNQ currents in the regulation of the resting membrane potential of detrusor SMC and their important physiological function in the control of spontaneous contractility in the guinea pig bladder.

Optimisation and scaling of interfacial GeO2 layers for high-k gate stacks on germanium and extraction of dielectric constant of GeO2

Germanium is an attractive channel material for MOSFETs because of its higher mobility than silicon. In this paper, GeO2 has been investigated as an interfacial layer for high-kappa gate stacks on germanium. Thermally grown GeO2 layers have been prepared at 550 degrees C to minimise GeO volatilisation. GeO2 growth has been performed in both pure O-2 ambient and O-2 diluted with N-2. GeO2 thickness has been scaled down to approximately 3 nm. MOS capacitors have been fabricated using different GeO2 thicknesses with a standard high-kappa dielectric on top. Electrical properties and thermal stability have been tested up to at least 350 degrees C. The K value of GeO2 was experimentally determined to be 4.5. Interface state densities (D-it) of less than 10(12) CM-2 eV(-1) have been extracted for all devices using the conductance method.

Irresponsible Lending?: A Case Study of a U.K. Credit Industry Reform Initiative

There are major concerns about the level of personal borrowing, particularly sourced from credit cards. This paper charts the progress of an initiative to create a Responsible Lending Index (RLI) for the credit industry. The RLI proposed to voluntarily benchmark lending standards and promote best practice within the credit industry by involving suppliers of credit, customer representatives and regulators. However, despite initial support from some banks, consumer bodies and the Chair of the Treasury Select Committee, it failed to gain sufficient support from financial institutions in its original format. The primary reasons for this were related to the complexity of building such a robust index and the banks trade body’s fear of exposing its members to public scrutiny. A revised alternative, the Responsible Lending Initiative, was proposed which took into account these concerns. However, the Association of Payment Clearing Service (APACS), the trade body of the credit industry, then effectively destroyed the proposal. This article describes an attempt to address the challenges in the credit card industry with the initiation of the RLI, reflected in stakeholder discourse and in the context of a wider concern expressed by the involved stakeholders in terms of the need for greater responsibility in the banking industry’s lending practices.

Thermal conductivities of ionic liquids over the temperature range from 293 K to 353 K

The thermal conductivities of 11 ionic liquids were determined, over the temperature range from 293 K to 353 K, at atmospheric pressure, using an apparatus based on the transient hot-wire method. For each of the ionic liquids studied, the thermal conductivities were found to be between (0.1 and 0.2) W.m(-1).K-1, with a slight decrease observed on increasing temperature. The uncertainty is estimated to be less than +/- 0.002 W.m(-1).K-1. In all cases, a linear equation was found to give a good fit to the data. The effects of water content and chloride content on the thermal conductivities of some of the ionic liquids were investigated. In each case, the thermal conductivities of the water + ionic liquid and chloride + ionic liquid binary mixtures were found to be less than the weighted average of the pure component thermal conductivities. This effect was adequately modeled using the Jamieson correlation. Chloride contamination at typical postsynthesis levels was found to have no significant effect on the thermal conductivities of the ionic liquid studied.

Law, Politics and Financial Development: The Great Reversal of the U.K. Corporate Debt Market

This article examines the role of creditor protection in the development of the U.K. corporate bond market. This market grew rapidly in the late nineteenth century, but in the twentieth century it experienced a reversal, albeit with a short-lived post-1945 renaissance. Such was the extent of the reversal that the market from the 1970s onwards was smaller than it had been in 1870. We find that law does not explain the variation in the size of this market over time. Alternatively, our evidence suggests that inflation and taxation policies were major drivers of this market in the post-1945 era. Copyright © The Economic History Association 2013

Preliminary Report of the 1 field season at Gubbio.:Malone, C.A.T. and S.K.F. Stoddart,

Xerox circulation to sponsors. Cambridge University.

Review of: Tykot, R.H. and Andrews, T.K. 1992. Sardinia: a footprint in the sea: studies in Sardinian Archaeology presented to Miriam Balmuth. Sheffield Academic Press

Proceedings of the Prehistoric Society, 1994. 60: p. 455-6.

K-Theory of Azumaya Algebras over Schemes

Let X be a connected, noetherian scheme and A{script} be a sheaf of Azumaya algebras on X, which is a locally free O{script}-module of rank a. We show that the kernel and cokernel of K(X) ? K(A{script}) are torsion groups with exponent a for some m and any i = 0, when X is regular or X is of dimension d with an ample sheaf (in this case m = d + 1). As a consequence, K(X, Z/m) ? K(A{script}, Z/m), for any m relatively prime to a. © 2013 Copyright Taylor and Francis Group, LLC.

The Role of K+ and Cl- Channels in the Regulation of Retinal Arteriolar Tone and Blood Flow

Purpose: This study tested the role of K(+)- and Cl(-)-channels in retinal arteriolar smooth muscle in the regulation of retinal blood flow.

Methods: Studies were carried out in adult Male Hooded Lister rats. Selectivity of ion channel blockers was established using electrophysiological recordings from smooth muscle in isolated arterioles under voltage clamp conditions. Leukocyte velocity and retinal arteriolar diameters were measured in anesthetised animals using leukocyte fluorography and fluorescein angiography imaging with a confocal scanning laser ophthalmoscope. These values were used to estimate volumetric flow, which was compared between control conditions and following intravitreal injections of ion channel blockers, either alone or in combination with the vasoconstrictor potent Endothelin 1 (Et1).

Results: Voltage activated K(+)-current (IKv) was inhibited by correolide, large conductance (BK) Ca(2+)-activated K(+)-current (IKCa) by Penitrem A, and Ca(2+)-activated Cl(-)-current (IClCa) by disodium 4,4'-diisothiocyanatostilbene-2,2'-disulfonate (DIDS). Intravitreal injections (10µl) of DIDS (estimated intraocular concentration 10mM) increased flow by 22%, whereas the BK-blockers Penitrem A (1µM) and iberiotoxin (4µM), and the IKv-inhibitor correolide (40µM) all decreased resting flow by approximately 10%. Et1 (104nM) reduced flow by almost 65%. This effect was completely reversed by DIDS but was unaffected by Penitrem A, iberiotoxin or correolide.

Conclusions: These results suggest that Cl(-)-channels in retinal arteriolar smooth muscle limit resting blood flow and play an obligatory role in Et1 responses. K(+)-channel activity promotes basal flow but exerts little modifying effect on the Et1 response. Cl(-)-channels may be appropriate molecular targets in retinal pathologies characterised by increased Et1 activity and reduced blood flow.