Summary and general conclusions: Childbearing Trends and Policies in Europe

European fertility early in the 21st century was at its lowest level since the Second World War. This study explores contemporary childbearing trends and policies in Europe, and gives detailed attention to the past two or three decades. We felt motivated to undertake this project because in many European countries, as well as for the European Union as a whole, the overall fertility level and its consequences are of grave concern and draw attention on the political stage. Our account focuses somewhat more on the previously state socialist countries of Central and Eastern Europe, where available knowledge about the impact on childbearing of the momentous political and economic transition that started in 1989 remains relatively scarce. As family formation and childbearing behaviour are inherent components of societal life, they were influenced and modified by the various political, economic, and social changes that took place in Europe during the past 60 years. There were also profound changes in norms, values, beliefs, and attitudes regarding family and childbearing, and these exerted additional effects on fertility and family trends. To identify such effects, this study pays much attention to the influence of social and family policies on fertility, to the influence of political and economic changes on fertility and family trends, and to the diverse ways changes in values, norms, and attitudes relate to the transformation in family-related behaviour in Europe. In the present chapter, we outline main issues discussed in the subsequent overview chapters, and summarise the main findings of the entire study.childbearing, Europe

ELMAG: A Monte Carlo simulation of electromagnetic cascades on the extragalactic background light and in magnetic fields

A Monte Carlo program for the simulation of electromagnetic cascades initiated by high-energy photons and electrons interacting with extragalactic background light (EBL) is presented. Pair production and inverse Compton scattering on EBL photons as well as synchrotron losses and deflections of the charged component in extragalactic magnetic fields (EGMF) are included in the simulation. Weighted sampling of the cascade development is applied to reduce the number of secondary particles and to speed up computations. As final result, the simulation procedure provides the energy, the observation angle, and the time delay of secondary cascade particles at the present epoch. Possible applications are the study of TeV blazars and the influence of the EGMF on their spectra or the calculation of the contribution from ultrahigh energy cosmic rays or dark matter to the diffuse extragalactic gamma-ray background. As an illustration, we present results for deflections and time-delays relevant for the derivation of limits on the EGMF.Comment: 10 pages, 5 eps figures; program available at http://elmag.sourceforge.net; v2 matches published versio

Correlated connectivity and the distribution of firing rates in the neocortex

Two recent experimental observations pose a challenge to many cortical models. First, the activity in the auditory cortex is sparse, and firing rates can be described by a lognormal distribution. Second, the distribution of non-zero synaptic strengths between nearby cortical neurons can also be described by a lognormal distribution. Here we use a simple model of cortical activity to reconcile these observations. The model makes the experimentally testable prediction that synaptic efficacies onto a given cortical neuron are statistically correlated, i.e. it predicts that some neurons receive many more strong connections than other neurons. We propose a simple Hebb-like learning rule which gives rise to both lognormal firing rates and synaptic efficacies. Our results represent a first step toward reconciling sparse activity and sparse connectivity in cortical networks

Reviewing the effects of food provisioning on wildlife immunity

While urban expansion increasingly encroaches on natural habitats, many wildlife species capitalize on anthropogenic food resources, which have the potential to both positively and negatively influence their responses to infection. Here we examine how food availability and key nutrients have been reported to shape innate and adaptive immunity in wildlife by drawing from field-based studies, as well as captive and food restriction studies with wildlife species. Examples of food provisioning and key nutrients enhancing immune function were seen across the three study type distinctions, as were cases of trace metals and pharmaceuticals impairing the immunity of wildlife species. More generally, food provisioning in field studies tended to increase innate and adaptive responses to certain immune challenges, whereas patterns were less clear in captive studies. Mild food restriction often enhanced, whereas severe food restriction frequently impaired immunity. However, to enable stronger conclusions we stress a need for further research, especially field studies, and highlight the importance of integrating nutritional manipulation, immune challenge, and functional outcomes. Despite current gaps in research on this topic, modern high throughput molecular approaches are increasingly feasible for wildlife studies and offer great opportunities to better understand human influences on wildlife health.This article is part of the theme issue 'Anthropogenic resource subsidies and host-parasite dynamics in wildlife'

Densidade de Rhea americana em três paisagens diferentes no Pantanal da Nhecolândia.

Pecuária em campos nativos constitui uma atividade tradicional no Pantanal brasileiro. Contudo, tem um aumento na substituição de vegetação nativa por pastagens cultivadas de espécies exóticas. As respostas da fauna local em relação a essas transformações ainda são pouco conhecidas. O objetivo do trabalho foi estimar a densidade de ema, Rhea americana, em três diferentes paisagens, para verificar como as densidades de ema respondem a estas diferenças. Cattle ranching on native grasslands is a traditional activity in the Brazilian Pantanal. However, recently there is an increase in the replacement of the native vegetation by cultivated pastures with exotic species. The responses of the local fauna in relation to these changes are still poorly known. The objective of this study was to estimate the density of rhea, Rhea americana, in three landscapes in order to assess the response population density to these differences

TeV gamma-rays from UHECR interactions in AGN cores: Lessons from Centaurus A

TeV gamma-rays have been observed from blazars as well as from radio galaxies like M87 and Cen A. In leptonic models, gamma-rays above the pair production threshold can escape from the ultra-relativistic jet, since large Lorentz factors reduce the background photon densities compared to those required for isotropic emission. Here we discuss an alternative scenario, where VHE photons are generated as secondaries from UHECR interaction in the AGN core. We show that TeV gamma-rays can escape from the core despite large IR and UV backgrounds. For the special case of Cen A, we study if the various existing observations from the far infra-red to the UHE range can be reconciled within this picture.Comment: 7 pages, 11 eps figures; v2: to appear in a special Cen A issue of PAS