Seabird metapopulations: searching for alternative breeding habitats

Today, many seabird species nest in port areas, which are also necessary for human economic activity. In this paper, we evaluate, using a metapopulation model, the possibilities for creating alternative breeding sites for the Common Tern (Sterna hirundo) in the Rhine¿Meuse¿Scheldt estuary. We explore 22 scenarios that differ with respect to (1) loss of breeding habitat in port areas, (2) location and size of newly created habitat, and (3) coexistence of old and new habitat. Results indicate that loss of port area habitats results in a serious 41% decline in the breeding population. When the loss in ports is compensated for within the ports, the decline was negligible. Fourteen scenarios result in an increase of the Common Tern metapopulation. In these, extra breeding habitat is created outside the ports in fish-rich waters, resulting in a potential metapopulation increase of 25%. However, the period of overlap between lost and newly created habitat strongly affects the results. A gap between the removal of old and the creation of new breeding areas might cause a drop in the metapopulation level of 30%. The population recovery from this drop might take more than 100 years due to slow recolonization. Our results suggest that conservation of seabird species should be evaluated on a metapopulation scale and that the creation of new habitat may help to compensate for habitat loss in other areas. Furthermore, the results indicate that overlap between the existence of old and newly created breeding habitats is crucial for the success of compensation efforts. However, new locations should be carefully selected, because not only is the suitability of the breeding grounds important, but ample fish availability nearby is also ke

Polynomial Chaos Expansion method as a tool to evaluate and quantify field homogeneities of a novel waveguide RF Wien Filter

For the measurement of the electric dipole moment of protons and deuterons, a novel waveguide RF Wien filter has been designed and will soon be integrated at the COoler SYnchrotron at J\"ulich. The device operates at the harmonic frequencies of the spin motion. It is based on a waveguide structure that is capable of fulfilling the Wien filter condition ($\vec{E} \perp \vec{B}$) \textit{by design}. The full-wave calculations demonstrated that the waveguide RF Wien filter is able to generate high-quality RF electric and magnetic fields. In reality, mechanical tolerances and misalignments decrease the simulated field quality, and it is therefore important to consider them in the simulations. In particular, for the electric dipole moment measurement, it is important to quantify the field errors systematically. Since Monte-Carlo simulations are computationally very expensive, we discuss here an efficient surrogate modeling scheme based on the Polynomial Chaos Expansion method to compute the field quality in the presence of tolerances and misalignments and subsequently to perform the sensitivity analysis at zero additional computational cost.Comment: 12 pages, 19 figure

Electromagnetic Simulation and Design of a Novel Waveguide RF Wien Filter for Electric Dipole Moment Measurements of Protons and Deuterons

The conventional Wien filter is a device with orthogonal static magnetic and electric fields, often used for velocity separation of charged particles. Here we describe the electromagnetic design calculations for a novel waveguide RF Wien filter that will be employed to solely manipulate the spins of protons or deuterons at frequencies of about 0.1 to 2 MHz at the COoler SYnchrotron COSY at J\"ulich. The device will be used in a future experiment that aims at measuring the proton and deuteron electric dipole moments, which are expected to be very small. Their determination, however, would have a huge impact on our understanding of the universe.Comment: 10 pages, 10 figures, 4 table

Long-Term Consequences of Hepatitis C Viral Clearance on the CD4 (+) T Cell Lymphocyte Course in HIV/HCV Coinfected Patients

The long-term impact of pegylated-interferon plus ribavirin treatment outcome on CD4 T cell course in patients coinfected with human immunodeficiency virus and hepatitis C virus is largely unclear in the literature. The aim of this study was to investigate the impact of HCV-RNA clearance by standard anti-HCV therapy on long-term CD4 cells recovery in HIV/HCV patients on successful combined antiretroviral therapy. We retrospectively enrolled HIV/HCV-coinfected patients on HIV medications and treated for hepatitis C. CD4 + T cell counts were registered at baseline and after hepatitis C therapy. Multiple linear regression analysis was performed to identify independent predictors of CD4 + T cell change following the anti-HCV treatment outcome. Of the 116 patients enrolled, 54 (46.6%) reached a sustained virological response. During a follow-up of 24 months, the SVR group showed a mean annual increase in CD4 + T cell from baseline of 84 cells/ll at 1 year and of a further 38 cells/ll within the second year (P=0.01, 0.001, resp.). An insignificant mean increase of 77 cells/ll occurred in the non-SVR group within month 24 (P=0.06). Variables associated with greater CD4 gains were higher nadir, lower preinterferon CD4 counts, and lower body mass index (BMI)

The effect of dietary fish oil on weight gain and insulin sensitivity is dependent on APOE genotype in humanized targeted replacement mice

We investigated the independent and interactive impact of the common APOE genotype and marine n-3 polyunsaturated fatty acids (PUFA) on the development of obesity and associated cardiometabolic dysfunction in a murine model. Human APOE3 and APOE4 targeted replacement mice were fed either a high-fat control diet (HFD) or a HFD supplemented with 3% n-3 PUFA from fish oil (HFD + FO) for 8 wk. We established the impact of intervention on food intake, bodyweight, and visceral adipose tissue (VAT) mass; plasma, lipids (cholesterol and triglycerides), liver enzymes, and adipokines; glucose and insulin during an intraperitoneal glucose tolerance test; and Glut4 and ApoE expression in VAT. HFD feeding induced more weight gain and higher plasma lipids in APOE3 compared to APOE4 mice (P < 0.05), along with a 2-fold higher insulin and impaired glucose tolerance. Supplementing APOE3, but not APOE4, animals with dietary n-3 PUFA decreased bodyweight gain, plasma lipids, and insulin (P < 0.05) and improved glucose tolerance, which was associated with increased VAT Glut4 mRNA levels (P < 0.05). Our findings demonstrate that an APOE3 genotype predisposes mice to develop obesity and its metabolic complications, which was attenuated by n-3 PUFA supplementation.—Slim, K. E., Vauzour, D., Tejera, N., Voshol, P. J., Cassidy, A., Minihane, A. M. The effect of dietary fish oil on weight gain and insulin sensitivity is dependent on APOE genotype in humanized targeted replacement mice

High-global warming potential F-gas emissions in California: comparison of ambient-based versus inventory-based emission estimates, and implications of refined estimates.

To provide information for greenhouse gas reduction policies, the California Air Resources Board (CARB) inventories annual emissions of high-global-warming potential (GWP) fluorinated gases, the fastest growing sector of greenhouse gas (GHG) emissions globally. Baseline 2008 F-gas emissions estimates for selected chlorofluorocarbons (CFC-12), hydrochlorofluorocarbons (HCFC-22), and hydrofluorocarbons (HFC-134a) made with an inventory-based methodology were compared to emissions estimates made by ambient-based measurements. Significant discrepancies were found, with the inventory-based emissions methodology resulting in a systematic 42% under-estimation of CFC-12 emissions from older refrigeration equipment and older vehicles, and a systematic 114% overestimation of emissions for HFC-134a, a refrigerant substitute for phased-out CFCs. Initial, inventory-based estimates for all F-gas emissions had assumed that equipment is no longer in service once it reaches its average lifetime of use. Revised emission estimates using improved models for equipment age at end-of-life, inventories, and leak rates specific to California resulted in F-gas emissions estimates in closer agreement to ambient-based measurements. The discrepancies between inventory-based estimates and ambient-based measurements were reduced from -42% to -6% for CFC-12, and from +114% to +9% for HFC-134a