A Population Based Regional Dynamic Microsimulation of Germany: The MikroSim Model

Microsimulation models are widely used to evaluate the potential effects of different policies on social indicators. Most microsimulation models in use operate on a national level, disregarding regional variations. We describe the construction of a national microsimulation model for Germany, accounting for local variations in each of the more than 10,000 communities in Germany. The database used and the mechanisms implementing the population dynamics are described. Finally, the further development of the database and microsimulation programs are outlined, which will contribute towards a research lab that will be made available to the wider scientific community

The first known virus isolates from Antarctic sea ice have complex infection patterns

Viruses are recognized as important actors in ocean ecology and biogeochemical cycles, but many details are not yet understood. We participated in a winter expedition to the Weddell Sea, Antarctica, to isolate viruses and to measure virus-like particle abundance (flow cytometry) in sea ice. We isolated 59 bacterial strains and the first four Antarctic sea-ice viruses known (PANV1, PANV2, OANV1 and OANV2), which grow in bacterial hosts belonging to the typical sea-ice genera Paraglaciecola and Octadecabacter. The viruses were specific for bacteria at the strain level, although OANV1 was able to infect strains from two different classes. Both PANV1 and PANV2 infected 11/15 isolated Paraglaciecola strains that had almost identical 16S rRNA gene sequences, but the plating efficiencies differed among the strains, whereas OANV1 infected 3/7 Octadecabacter and 1/15 Paraglaciecola strains and OANV2 1/7 Octadecabacter strains. All the phages were cold-active and able to infect their original host at 0 degrees C and 4 degrees C, but not at higher temperatures. The results showed that virus-host interactions can be very complex and that the viral community can also be dynamic in the winter-sea ice.Peer reviewe

Sexual Conflict and the Tragedy of the Commons

It is widely understood that the costs and benefits of mating can affect the fecundity and survival of individuals. Sexual conflict may have profound consequences for populations as a result of the negative effects it causes males and females to have on one another's fitness. Here we present a model describing the evolution of sexual conflict, in which males inflict a direct cost on female fitness. We show that these costs can drive the entire population to extinction. To males, females are an essential but finite resource over which they have to compete. Population extinction owing to sexual conflict can therefore be seen as an evolutionary tragedy of the commons. Our model shows that a positive feedback between harassment and the operational sex ratio is responsible for the demise of females and, thus, for population extinction. We further show that the evolution of female resistance to counter harassment can prevent a tragedy of the commons. Our findings not only demonstrate that sexual conflict can drive a population to extinction but also highlight how simple mechanisms, such as harassment costs to males and females and the coevolution between harassment and resistance, can help avert a tragedy of the commons caused by sexual conflict

CD4+ CD25+ regulatory T cells in human pregnancy: development of a Treg-MLC-ELISPOT suppression assay and indications of paternal specific Tregs

The current study was aimed at developing a one-way mixed leucocyte culture–enzyme-linked immunospot (MLC-ELISPOT) assay for the study of CD4+ CD25+ regulatory T (Treg) cells and applying this method in the study of antifetal immune reactions during human pregnancy. Twenty-one pregnant women and the corresponding fathers-to-be, and 10 non-pregnant control women and men, participated in the study. CD4+ CD25+ cells were isolated from peripheral blood mononuclear cells (PBMC) by immunomagnetic selection. Maternal/control PBMC were stimulated with paternal or unrelated PBMC in MLC. Secretion of interleukin-4 (IL-4) and interferon-γ (IFN-γ) from responder cells, with or without the presence of autologous Treg cells, was analysed by ELISPOT. PBMC from pregnant women showed increased secretion of IL-4 compared to controls. In pregnant and non-pregnant controls, Treg cells suppressed IFN-γ reactivity against paternal and unrelated alloantigens. Interestingly, Treg cells suppressed IL-4 secretion against paternal but not unrelated alloantigens during pregnancy. We have successfully developed a model for studying Treg cells in antifetal cytokine reactions during pregnancy. Results indicate that Treg cells contribute to strict regulation of both T helper type 1-like and type 2-like antifetal immune reactions. Interestingly, T helper type 2-like cells specific to unrelated alloantigens are able to escape the suppression of Treg cells, which would allow for IL-4, alongside CD4+ CD25+ Treg cells, to control potentially detrimental IFN-γ reactions during pregnancy

Deliverable 3.2 - Guidelines for best practices implementation for transferring methodology

Today, big data is a buzz word. Although there have been attempts to properly define the term, a really universally accepted definition has not yet been given. Accordingly, many different types of data may be classified as big data or new data. These range from scanner data collected at retail outlets, through remote sensing data to mobile phone data. As the availability of such data increases, researchers try to make use of them by incorporating them into existing methods and developing new methods. These developments are also highly relevant for the estimation of well-being indicators, a core focus of the MAKSWELL project. The combination of new data sources and new or modified methods are promising especially where the estimation of well-being at a fine spatial resolution is concerned. While a comprehensive survey of the related literature and available data sets is out of the scope of this project, this deliverable collects a few (experimental) applications that shed a light on the potential benefits of these new approaches. Some drawbacks and practical implementation problems are addressed as well. Taken as a whole, the presented set of applications points to future research needs in the area and allows the derivation of some general best practice guidelines that can also inform other subject matter areas beside the measurement of poverty and well-being