Persistent negative effects of pesticides on biodiversity and biological control potential on European farmland

During the last 50 years, agricultural intensification has caused many wild plant and animal species to go extinct regionally or nationally and has profoundly changed the functioning of agro-ecosystems. Agricultural intensification has many components, such as loss of landscape elements, enlarged farm and field sizes and larger inputs of fertilizer and pesticides. However, very little is known about the relative contribution of these variables to the large-scale negative effects on biodiversity. In this study, we disentangled the impacts of various components of agricultural intensification on species diversity of wild plants, carabids and ground-nesting farmland birds and on the biological control of aphids.

Voltage-activated currents in cardiac myocytes of the blue mussel, Mytilus edulis

Voltage-sensitive ionic currents were identified and characterised in ventricular myocytes of the bivalve mollusc, Mytilus edulis, using the whole-cell patch-clamp technique. Two outward currents could be distinguished. A potassium A current (I-A) activated at - 30 mV from a holding potential of - 60 mV. This transient current was inactivated by holding the cells at a potential of - 40 mV and was also blocked by applying 4-aminopyridine (3 mM) to the external bath solution. A second current was identified as a delayed rectifier (I-K). This also activated at - 30 mV but exhibited a sustained time course and was still activated at a holding potential of - 40 mV. Both outward currents were reduced in the presence of tetraethylammonium ions (30 mM). A small number of heart cells also showed an inward sodium current (I-Na). This current appeared at potentials more positive than - 50 mV, reached a maximum at - 20 mV, and decreased with further depolarisation. I-Na was inactivated at a holding potential of - 40 mV and was blocked by tetrodotoxin (1 mu M). A second inward current had a sustained time course and was not inactivated by holding the cell at a potential of -40 mV, and was also not abolished by tetrodotoxin. This current peaked at 0 mV, decreasing with further depolarisation. Furthermore, it was enhanced by the addition of barium ions (3 mM) to the bath and was blocked by external cobalt (2 mM) or nifedipine (15 mu M) These findings are consistent with this being an L-type calcium current (I-Ca) The possible physiological roles of these currents in M. edulis heart are discussed. (C) 1999 Elsevier Science Inc. All rights reserved.

The Respiratory Syncytial Virus G Protein Conserved Domain Induces a Persistent and Protective Antibody Response in Rodents

Respiratory syncytial virus (RSV) is an important cause of severe upper and lower respiratory disease in infants and in the elderly. There are 2 main RSV subtypes A and B. A recombinant vaccine was designed based on the central domain of the RSV-A attachment G protein which we had previously named G2Na (aa130–230). Here we evaluated immunogenicity, persistence of antibody (Ab) response and protective efficacy induced in rodents by: (i) G2Na fused to DT (Diphtheria toxin) fragments in cotton rats. DT fusion did not potentiate neutralizing Ab responses against RSV-A or cross-reactivity to RSV-B. (ii) G2Nb (aa130–230 of the RSV-B G protein) either fused to, or admixed with G2Na. G2Nb did not induce RSV-B-reactive Ab responses. (iii) G2Na at low doses. Two injections of 3 µg G2Na in Alum were sufficient to induce protective immune responses in mouse lungs, preventing RSV-A and greatly reducing RSV-B infections. In cotton rats, G2Na-induced RSV-reactive Ab and protective immunity against RSV-A challenge that persisted for at least 24 weeks. (iv) injecting RSV primed mice with a single dose of G2Na/Alum or G2Na/PLGA [poly(D,L-lactide-co-glycolide]. Despite the presence of pre-existing RSV-specific Abs, these formulations effectively boosted anti-RSV Ab titres and increased Ab titres persisted for at least 21 weeks. Affinity maturation of these Abs increased from day 28 to day 148. These data indicate that G2Na has potential as a component of an RSV vaccine formulation.

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.

Transient Ca2+-activated Cl-currents with endothelin in isolated arteriolar smooth muscle cells of the choroid

To characterize the effects of endothelin (ET)-1 on the Ca2+-activated Cl- conductance of choroidal arteriolar smooth muscle.

Persistent income poverty and deprivation in the European Union: An analysis of the first three waves of the European Community Household Panel

Poverty research has increasingly focused on persistent income poverty, both as a crucial social indicator and as a target for policy intervention. Such an approach can lead to an identification of a sub-set of poor individuals facing particularly adverse circumstances and/or distinctive problems in escaping from poverty. Here we seek to establish whether, in comparison with cross-sectional measures, persistent poverty measures also provide a better measure of exclusion from a minimally acceptable way of life and relate with other important variables in a logical fashion. Our analysis draws upon the first three waves of the ECHP and shows that a persistent poverty measure does constitute a significant improvement over its cross-sectional counterpart in the explanation of levels of deprivation. Persistent poverty is related to life-style deprivation in a manner that comes close to being uniform across countries. The measure of persistence also conforms to our expectations of how a poverty measure should behave in that, unlike relative income poverty lines, defining the threshold level more stringently enables us to identify progressively groups of increasingly deprived respondents. Overall the persistent poverty measure constitutes a significant advance on cross-sectional income measures. However, there is clearly a great deal relating to the process of accumulation and of erosion of resources, which is not fully captured in the persistent poverty measure. In the absence of such information, there is a great deal to be said for making use of both types of indictors in formulating and evaluating policies while we continue to improve our understanding of longer-term processes.

Multiple deprivation and persistent poverty in the European Union

The literature on Social exclusion has focused attention on the processes leading to exposure to multiple disadvantage. Despite the influence this perspective has had on both academic and policy discussions, conceptual analysis has remained imprecise and empirical evidence modest. We have made use of the European Community Household Panel (ECHP) in order to examine the extent to which persistent income poverty results in multiple deprivation. Our analysis shows that only a modest proportion of the persistently poor can he characterized as being exposed to such deprivation. While persistent poverty and multiple deprivation combine to produce extremely high levels of economic strain, there is no evidence that they interact in a significant fashion. We argue that understanding deprivation is not facilitated by focusing on a cleavage between a multiply deprived minority and a comfortable majority, and we consider the policy implications of this argument.

Persistent and consistent poverty in the 1994 and 1995 waves of the European Community Household Panel Survey

This paper focuses on the mismatch between income and deprivation measures of poverty. Using the first two waves of the European Community Household Panel Survey, a measure of relative deprivation is constructed and the overlap between the relative income poor and relatively deprived is examined, There is very limited overlap with the lowest relative income threshold. The overlap increases as the income threshold is raised, but it remains true that less than half those below the 60 percent relative income line are among the most deprived. Relative deprivation is shown to be related to the persistence of income poverty, but also to a range of other resource and need factors. Income and deprivation measures each contain information that can profitably be employed to enhance our understanding of poverty and a range of other social phenomena. This is illustrated by the manner in which both income poverty and relative deprivation are associated with self-reported difficulty making ends meet.

Electric currents and lens regeneration in the rat

We studied the process of lens regeneration in the rat following an extracapsular lens extraction preserving the anterior lens capsule and anterior lens epithelium. We assessed clinically the clarity of the newly regenerated lens, evaluated changes in the lens electrical currents following surgery and during the regeneration process and correlated these changes with findings on light microscopy. Protein analysis of the regenerated lens was also undertaken. Experiments were performed in 41 Sprague-Dawley rats, sacrificed at 0, 2, 4 and 8 weeks postoperatively. Our results showed that complete lens regeneration occurred 8 weeks postoperatively only if the anterior epithelium was preserved and the lens capsule was closed surgically. Lens electrical currents, altered following surgery, recovered in parallel with the process of regeneration of the lens. The newly regenerated lens was optically clear and biochemical analysis revealed a pattern of protein expression resembling that observed during lens development. In conclusion, complete lens regeneration occurs in the rat and it is possible that lens electrical signals, together with other cues, may play an important role in this process. © 2009 Elsevier Ltd.

Demarcation laser therapy in the management of macular-sparing persistent subretinal fluid after scleral buckling procedures

Background: Persistent or recurrent macular-sparing subretinal fluid (SRF) can sometimes occur following scleral buckling procedures. Observation and reoperation have been used in the management of such cases. Demarcation laser therapy (DLT) has been used to treat macular-sparing retinal detachments in the context of cytomegalovirus retinitis and as primary treatment for selected rhegmatogenous retinal detachments. There are, however, scarce data in the literature regarding its use following primary scleral buckling procedures. The current study explores the use of DLT under the latter circumstances. Methods: The medical records of all consecutive patients with persistent SRF sparing the macula following primary rhegmatogenous retinal detachment repair using a scleral buckling procedure were retrospectively reviewed. Only those patients in whom the breaks were localised to the area of indentation and, thus, seemed to be well supported by the buckle were included. Demographics, clinical characteristics of the retinal detachment prior to scleral buckling, extension of the residual SRF observed postoperatively, details of the laser procedure, anatomical and functional outcomes and complications were evaluated. Results: Seven patients, all females, with a mean age of 47.9 years (range: 20-81) were included in the study. The retinal detachments were superior (n=3), inferior (n=3) and subtotal, affecting both superior and inferior retina (n=1). Scleral buckling procedures were used to treat the retinal detachments in all cases. Following demarcation laser therapy, the area of SRF remained stable in two patients, and flattened in four. In one patient, extension of SRF occurred requiring further surgery. Conclusions: Demarcation laser therapy appears to be a reasonable option in the management of patients with persistent or recurrent SRF sparing the macula following scleral buckling surgery. © Springer-Verlag 2006.

The effects of global climate change on the cycling and processes of persistent organic pollutants (POPs) in the North Sea

The fate and cycling of two selected legacy persistent organic pollutants (POPs), PCB 153 and gamma-HCH, in the North Sea in the 21st century have been modelled with combined hydrodynamic and fate and transport ocean models
(HAMSOM and FANTOM, respectively). To investigate the impact of climate variability on POPs in the North Sea in the 21st century, future scenario model runs for three 10-year periods to the year 2100 using plausible levels of both in
situ concentrations and atmospheric, river and open boundary inputs are performed. This slice mode under a moderate scenario (A1B) is sufficient to provide a basis for further analysis. For the HAMSOM and atmospheric forcing, results of the IPCC A1B (SRES) 21st century scenario are utilized, where surface forcing is provided by the REMO downscaling of the ECHAM5 global atmospheric model, and open boundary conditions are provided by the MPIOM global ocean model.
Dry gas deposition and volatilization of gamma-HCH increase in the future relative to the present by up to 20% (in the spring and summer months for deposition and in summer for volatilization). In the water column, total mass of
gamma-HCH and PCB 153 remain fairly steady in all three runs. In sediment,
gamma-HCH increases in the future runs, relative to the present, while PCB 153 in sediment decreases exponentially in all three runs, but even faster in the future, due to the increased number of storms, increased duration of gale wind conditions and increased water and air temperatures, all of which are the result of climate change. Annual net sinks exceed sources at the ends of all periods.
Overall, the model results indicate that the climate change scenarios considered here generally have a negligible influence on the simulated fate and transport of the two POPs in the North Sea, although the increased number and magnitude of storms in the 21st century will result in POP resuspension and ensuing revolatilization events. Trends in emissions from primary and secondary sources will remain the key driver of levels of these contaminants over time.

Modelling the fate of persistent organic pollutants (POPs) in the North Sea system

The environmental fate of selected persistent organic pollutants (POPs) in the North Sea system is modelled with a high resolution Fate and Transport Ocean Model (FANTOM) that uses hydrodynamic model output from the Hamburg Shelf Ocean Model (HAMSOM). Large amounts of POPs enter the North Sea from the surrounding highly populated, industrialised and agricultural countries. Major pathways to the North Sea are atmospheric deposition and river inputs, with additional contributions coming from bottom sediments and adjacent seas. The model domain covers the entire North Sea region, extending northward as far as the Shetland Islands, and includes adjacent basins such as the Skagerrak, Kattegat, and the westernmost part of the Baltic Sea. Model resolution (for both models) is 1.5’ latitude x 2.5’ longitude (approximately 3 km horizontal resolution) with 30 vertical levels. The POP model also has 20 sediment layers. Important model processes controlling the fate of POPs in the North Sea system are discussed. Results focus on Lindane gamma- HCH or gamma-hexachlorocyclohexane) and PCB 153.

Polarization retention loss in PbTiO3 ferroelectric films due to leakage currents

The relationship between retention loss in single crystal PbTiO3 ferroelectric thin films and leakage currents is demonstrated by piezoresponse and conductive atomic force microscopy measurements. It was found that the polarization reversal in the absence of an electric field followed a stretched exponential behavior 1-exp[-(t/k)(d)] with exponent d>1, which is distinct from a dispersive random walk process with d <. The latter has been observed in polycrystalline films for which retention loss was associated with grain boundaries. The leakage current indicates power law scaling at short length scales, which strongly depends on the applied electric field. Additional information of the microstructure, which contributes to an explanation of the presence of leakage currents, is presented with high resolution transmission electron microscopy analysis.

The persistent activity of Jupiter-family comets at 3-7 AU

We present an analysis of comet activity based on the Spitzer Space Telescope component of the Survey of the Ensemble Physical Properties of Cometary Nuclei. We show that the survey is well suited to measuring the activity of Jupiter-family comets at 3-7 AU from the Sun. Dust was detected in 33 of 89 targets (37 ± 6%), and we conclude that 21 comets (24 ± 5%) have morphologies that suggest ongoing or recent cometary activity. Our dust detections are sensitivity limited, therefore our measured activity rate is necessarily a lower limit. All comets with small perihelion distances (q <1.8 AU) are inactive in our survey, and the active comets in our sample are strongly biased to post-perihelion epochs. We introduce the quantity ɛfρ, intended to be a thermal emission counterpart to the often reported Afρ, and find that the comets with large perihelion distances likely have greater dust production rates than other comets in our survey at 3-7 AU from the Sun, indicating a bias in the discovered Jupiter-family comet population. By examining the orbital history of our survey sample, we suggest that comets perturbed to smaller perihelion distances in the past 150 yr are more likely to be active, but more study on this effect is needed.

A new method for transmission loss allocation considering the circulating currents between generators

A new method is presented for transmission loss allocation based on the separation of transmission loss caused by load and the loss due to circulating currents between generators. The theoretical basis for and derivation of the loss formulae are presented using simple systems. The concept is then extended to a general power system using the Ybus model. Details of the application of the proposed method to a typical power system are presented along with results from the IEEE 30 bus test system. The results from both the small system and the standard IEEE test system demonstrate the validity of the proposed method.