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The purpose of this study was to improve understanding of the relationship between the spatial patterns of an important insect pest, the aphidMyzus persicae, and aspects of its environment. The main objectives were to determine the predominant geographical, climatic and land use factors that are linked with the aphid's distribution, to quantify their role in determining that distribution, including their interacting effects and to explore the ability of artificial neural networks (ANNs) to provide predictive models.The study focused on four spatial scales to account for the aphid data base characteristics and available land use data sets: Europe; a broad zone over Europe covering Belgium, Denmark, France, Ireland, Italy, The Netherlands, Scotland, Sweden and Wales (Regio data base coverage); North-West Europe (i.e. Belgium, France and the United Kingdom); and England with Wales.Multiple linear regression (MLR) was used to identify the variables in the Geographic location, Climate and Land use groups, that explained significant proportions of the variance inM. persicaetotal annual numbers and Julian date of first capture. A variance partitioning procedure was used to measure the fraction of the variation that can be explained by each environmental factor and of shared variation between the different factors. Finally, ANNs were employed as an alternative modelling approach for the two largest study areas, i.e. Europe and the Regio data base coverage, to determine whether the relationship between aphid and environmental variables was better described by more complex functions as well as their ability to generalize to new data.Land use variables are shown to play a significant role in explaining aphid numbers. The area of agricultural crops, in particular oilseed rape, is positively correlated withM. persicaeannual numbers. Among the climatic variables, rainfall is negatively correlated with aphid numbers and temperature is positively correlated. The geographical components also explain a significant part of aphid annual numbers. However, the variance partitioning procedure indicates that while each group has an effect, none is dominant. Aphid first capture is mainly explained by climate where rainfall tends to delay migration and warmer conditions tend to advance it. Climate accounts for the greatest part of the variance when considered separately from the other factors. The geographical and land use components also have a significant effect on first capture at each scale, but their direct contribution is negligible. The ability of the ANN models to generalize to new total numbers and phenological data compared with MLR models was less for Europe (9 and 6% increase in the variance accounted for, respectively) than for the Regio data coverage where an increase of 44% in the variance accounted for was observed.This research supports the hypothesis that climate, land use and geographical location play a role in determining patterns of aphid annual numbers and phenology. The ability of ANN models to predict aphid distribution is improved by the inclusion of temporal land use data. However, identification of the processes involved in such relationships is difficult due to numerous interactions between the environmental factors. [ABSTRACT FROM AUTHOR]

Objectives: Long-term safety and tolerability of ACC-001 (vanutide cridificar), an antiamyloid- beta therapeutic vaccine, was evaluated in subjects with mild to moderate Alzheimer's disease., Design: Phase 2a extension studies of randomized parent trials were conducted in the United States, European Union, and Japan., Methods: Four immunizations of ACC-001 were administered at the same 3 dose levels (3, 10, and 30 μg) to subjects randomized in the parent studies; ACC-001 was administered with QS-21 adjuvant. Safety, tolerability, and immunogenicity were assessed during active treatment and 6-month follow-up., Results: ACC-001 + QS-21 was well tolerated in the United States (N=110) and European Union (N=50), and Japan (N=53) extension studies; safety profile was similar to that observed in the parent studies, and no new safety signals were identified. Overall, injection site reactions were the most common adverse event in these studies. Anti-amyloid antibody titers were elicited in all groups, with the highest titers observed in subjects who received ACC-001 + QS-21 in both the parent and extension studies., Conclusions: Long-term exposure to ACC-001 + QS-21 was well tolerated in subjects with Alzheimer's disease, suggesting that side effects do not pose a principal limitation for anti-amyloid active immunotherapy. The highest anti-amyloid-beta IgG titers are elicited during long-term therapy with ACC-001 + QS-21 compared with other regimens., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Aims: The 6.6 Fr. Sprint Fidelis lead family may allow multiple lead implantation procedures with reduced risk of venous obstruction., Methods and Results: Two prospective, historically controlled, multi-centre studies were conducted in Europe (80 patients) and Canada (79 patients). The purpose was to assess the ventricular lead-related adverse events (LRAEs) and performance of the small Models 6948 and 6949 defibrillation leads, respectively, in patients with a standard indication for an ICD implant. Safety was assessed by demonstrating equivalence of the LRAE free rate at 1 month to comparable but larger leads (Models 6942, 6943, 6944, 6947and 4074). Seventy-five of 80 patients with a 6948 lead (93.8%) remained free of LRAEs. Seventy-four out of 79 patients (93.7%) with the 6949 lead remained free of LRAEs. The 95% lower confidence bounds were above the critical difference limits. Thus, safety of the Sprint Fidelis((R)) leads is similar to that of larger leads. Electrical performance through 1-month follow-up proved to be acceptable in comparison with other established leads., Conclusion: These multi-centre studies confirm that smaller defibrillation leads offer similar safety and efficacy features to widely used larger leads; they have low LRAE rates and defibrillation thresholds, while providing the advantage of a smaller introducer size and reduced venous obstruction.