Polysialylated neuropilin-2 enhances human dendritic cell migration through the basic C-terminal region of CCL21.

Free Access at: http://glycob.oxfordjournals.org/cgi/pmidlookup?view=long&pmid=20488940Dendritic cell (DC) migration to secondary lymphoid organs is a critical step to properly exert its role in immunity; and predominantly depends on the interaction of the chemokine receptor CCR7 with its ligands CCL21 and CCL19. Polysialic acid (PSA) has been recently reported to control CCL21-directed migration of mature DCs. Here; we first demonstrate that PSA present on human mature monocyte-derived dendritic cells did not enhance chemotactic responses to CCL19. We have also explored the molecular mechanisms underlying the selective enhancing effect of PSA on CCL21-driven chemotaxis of DCs. In this regard; we found out that prevention of DC polysialylation decreased CCL21 activation of JNK and Akt signaling pathways; both associated with CCR7-mediated chemotaxis. We also report that the enhanced PSA-mediated effect on DC migration towards CCL21 relied on the highly basic C-terminal region of this chemokine; and depended on the PSA acceptor molecule neuropilin-2 (NRP2) and on the polysialyltransferase ST8SiaIV. Altogether; our data indicate that the CCR7/CCL21/NRP2/ST8SiaIV functional axis constitutes an important guidance clue for DC targeting to lymphoid organs.This work was supported by research grant from Fondo de Investigaciones Sanitarias, Instituto de Salud Carlos III, Ministerio de Sanidad y Consumo (FISPI0708879 to MAV).Peer reviewe

Harnessing the biodiversity value of Central and Eastern European farmland

A large proportion of European biodiversity today depends on habitat provided by low-intensity farming practices, yet this resource is declining as European agriculture intensifies. Within the European Union, particularly the central and eastern new member states have retained relatively large areas of species-rich farmland, but despite increased investment in nature conservation here in recent years, farmland biodiversity trends appear to be worsening. Although the high biodiversity value of Central and Eastern European farmland has long been reported, the amount of research in the international literature focused on farmland biodiversity in this region remains comparatively tiny, and measures within the EU Common Agricultural Policy are relatively poorly adapted to support it. In this opinion study, we argue that, 10years after the accession of the first eastern EU new member states, the continued under-representation of the low-intensity farmland in Central and Eastern Europe in the international literature and EU policy is impeding the development of sound, evidence-based conservation interventions. The biodiversity benefits for Europe of existing low-intensity farmland, particularly in the central and eastern states, should be harnessed before they are lost. Instead of waiting for species-rich farmland to further decline, targeted research and monitoring to create locally appropriate conservation strategies for these habitats is needed now.Peer reviewe

Equilibrium Selection in Sequential Games with Imperfect Information

Games with imperfect information often feature multiple equilibria, which depend on beliefs off the equilibrium path. Standard selection criteria such as passive beliefs, symmetric beliefs or wary beliefs rest on ad hoc restrictions on beliefs. We propose a new selection criterion that imposes no restrictions on beliefs: we select the action profile that is supported in equilibrium by the largest set of beliefs. We conduct experiments to test the predictive power of the existing and our novel selection criteria in two applications: a game of vertical multi-lateral contracting, and a game of electoral competition. We find that our selection criterion outperforms the other selection criteria

A global analysis of Y-chromosomal haplotype diversity for 23 STR loci

In a worldwide collaborative effort, 19,630 Y-chromosomes were sampled from 129 different populations in 51 countries. These chromosomes were typed for 23 short-tandem repeat (STR) loci (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385ab, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635, GATAH4, DYS481, DYS533, DYS549, DYS570, DYS576, and DYS643) and using the PowerPlex Y23 System (PPY23, Promega Corporation, Madison, WI). Locus-specific allelic spectra of these markers were determined and a consistently high level of allelic diversity was observed. A considerable number of null, duplicate and off-ladder alleles were revealed. Standard single-locus and haplotype-based parameters were calculated and compared between subsets of Y-STR markers established for forensic casework. The PPY23 marker set provides substantially stronger discriminatory power than other available kits but at the same time reveals the same general patterns of population structure as other marker sets. A strong correlation was observed between the number of Y-STRs included in a marker set and some of the forensic parameters under study. Interestingly a weak but consistent trend toward smaller genetic distances resulting from larger numbers of markers became apparent.Peer reviewe

Balance of Power and the Propensity of Conflict

We study the role of an imbalance in fighting strengths when players bargain in the shadow of conflict. Our experimental results suggest: In a simple bargaining game with an exogenous mediation proposal, the likelihood of conflict is independent of the balance of power. If bargaining involves endogenous demand choices, however, the likelihood of conflict is higher if power is more imbalanced. Even though endogenous bargaining outcomes reflect the players' unequal fighting strengths, strategic uncertainty causes outcomes to be most efficient when power is balanced. In turn, the importance of exogenous mediation proposals depends on the balance of power

Demografische Strukturveränderungen und Binnenwanderung in der Schweiz, 1850-1950

Vorliegende Dissertation verschafft einen systematischen Überblick über Migrationen und demografische Strukturveränderungen in der Schweiz zwischen 1850 und 1950, dem Jahrhundert der schienengebundenen Mobilität. Die empirische Arbeit trägt die gesamtschweizerisch verfügbaren Grundlagendaten von Volkszählungen und anderer amtlicher Statistiken zusammen und wertet sie mit computergestützten raumwirtschaftlichen Methoden aus. Zum Schliessen bestehender Datenlücken gelangen verschiedene Modellrechnungen zum Einsatz. Die resultierende Datenbasis ist in der Form von Excel-Tabellen aufbereitet und der vorliegenden Dissertation als Anhang 4 beigelegt (ab Sommer 2003 auch unter www.volkszaehlung.ch). Zentraler Bestandteil der Arbeit ist ein räumlicher Raster zur systematischen Analyse der Teilgebiete der Schweiz. 180 Bezirke und die zehn grössten Städte bilden die räumliche Grundstufe, die zu 5 Naturräumen (Mittelland, Alpen usw.), 16 Migrationsregionen (Einzugsgebiete von Städten) und 10 Bezirkstypen (städtisch, ländlich, industriell, touristisch usw.) zusammengefasst werden. Die demografische Performance dieser Teilgebiete wird in zeitlicher und räumlicher Hinsicht analysiert. Den zeitlichen Rahmen der Analyse bildet das Jahrhundert zwischen der Entstehung der ersten Eisenbahnen um 1850 und dem anbrechenden Zeitalter der Voll-Motorisierung 1950. Wo es möglich ist, wird dieser Rahmen erweitert auf die gesamten 200 Jahre des statistischen Zeitalters von der ersten helvetischen Zählung 1798 bis zur Volkszählung des Jahres 2000. In einem gesonderten Kapitel wird die demografische Struktur von 1910 mit derjenigen am Ende des 20. Jahrhunderts verglichen. Dabei wird der immer stärkere Bevölkerungsaustausch zwischen den Migrationsregionen sichtbar, der aber an den Grenzen der Sprachgebiete haltmacht: die demografischen Beziehungen zwischen der Deutsch- und Westschweiz haben sich im 20. Jahrhundert klar abgeschwächt. This study aims to provide a detailled overview of the principal demographic trends and population shifts in Switzerland from 1850 to 1950, a period that can be characterized as the first century of mass mobility, driven by the rapidly expanding railway network. The empirical work comprises a systematic evaluation of the available census data and other official statistics, enhanced by modern computer-aided analysis of regional economies over time. The author created six computer model calculations to narrow gaps in the raw data and build a coherent database. The resultant database in the form of xls files is included as Annex 4 (from summer 2003 see www.volkszaehlung.ch). To aid the analysis a spatial grid facilitating a comparison of the various Swiss regions was created. The 10 biggest cities and the 180 districts make up the main database, which encompass 5 major regions (e.g. lowlands, hills, Alps), 16 migration areas (i.e. surroundings of the big cities) and 10 types of districts (e.g. cities, industrial, agrarian). To illustrate greater detail, the demographic evolution of these regions is plotted on the grid. The author concentrates on the 100 years spanning the construction of the first Swiss railways around 1850 and the beginning of the era of mass motoring, circa 1950. Whenever possible the analysis draws on the full 200 years of available statistics ie, from the first national census in 1798 to the most recent one in 2000. One chapter is dedicated to comparing the demographic structure of 1910 with that existing at the end of the 20th century, highlighting the main demographic changes. This process illustrates how the various regions became increasingly inter- dependent during the period. However, the empirical evidence suggests that the growing demographic coherence amongst the 16 migration areas has given way to emerging divisions between the German and French speaking parts of Switzerland

ABD e-News September 2, 2005

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