Remembering the work of Phillip L. Geissler: A coda to his scientific trajectory

Phillip L. Geissler made important contributions to the statistical mechanics of biological polymers, heterogeneous materials, and chemical dynamics in aqueous environments. He devised analytical and computational methods that revealed the underlying organization of complex systems at the frontiers of biology, chemistry, and materials science. In this retrospective, we celebrate his work at these frontiers

Estrogen defines the dorsal-ventral limit of VEGF regulation to specify the location of the hemogenic endothelial niche

Genetic control of hematopoietic stem and progenitor cell (HSPC) function is increasingly understood; however, less is known about the interactions specifying the embryonic hematopoietic niche. Here, we report that 17beta-estradiol (E2) influences production of runx1+ HSPCs in the AGM region by antagonizing VEGF signaling and subsequent assignment of hemogenic endothelial (HE) identity. Exposure to exogenous E2 during vascular niche development significantly disrupted flk1+ vessel maturation, ephrinB2+ arterial identity, and specification of scl+ HE by decreasing expression of VEGFAa and downstream arterial Notch-pathway components; heat shock induction of VEGFAa/Notch rescued E2-mediated hematovascular defects. Conversely, repression of endogenous E2 activity increased somitic VEGF expression and vascular target regulation, shifting assignment of arterial/venous fate and HE localization; blocking E2 signaling allowed venous production of scl+/runx1+ cells, independent of arterial identity acquisition. Together, these data suggest that yolk-derived E2 sets the ventral boundary of hemogenic vascular niche specification by antagonizing the dorsal-ventral regulatory limits of VEGF

Remembering the Work of Phillip L. Geissler: A Coda to His Scientific Trajectory.

Phillip L. Geissler made important contributions to the statistical mechanics of biological polymers, heterogeneous materials, and chemical dynamics in aqueous environments. He devised analytical and computational methods that revealed the underlying organization of complex systems at the frontiers of biology, chemistry, and materials science. In this retrospective we celebrate his work at these frontiers

Remembering the Work of Phillip L. Geissler: A Coda to His Scientific Trajectory.

Phillip L. Geissler made important contributions to the statistical mechanics of biological polymers, heterogeneous materials, and chemical dynamics in aqueous environments. He devised analytical and computational methods that revealed the underlying organization of complex systems at the frontiers of biology, chemistry, and materials science. In this retrospective we celebrate his work at these frontiers.Royal Society (URF\R1\211144

Exploring Job Satisfaction in Private and Public Employment: Empirical Evidence from Greece

This paper analyses subjective job satisfaction (JS) responses by employees in the public and private sectors of the Greek labour market. Panel data covering the period 1995-2001 and a random effects ordered probit model are used for estimation purposes. The results of the econometric estimation show that a substantial JS differential exists between the two sectors, in every JS domain and always in favour of public employment. A typical ordered decomposition analysis indicates that about one-third of the difference in expected JS can be explained by differences in employee characteristics and two-thirds by unobserved sector-specific inbuilt features. The comparison of wage reductions, which a representative employee will be prepared to endure in order to avoid employment in the private sector, reveals that the regularity of working schedules is appreciated more than any other facet of JS. The obtained results enhance the existing apparatus for evaluating government policies in the labour market. Copyright 2007 The Authors; Journal compilation 2007 CEIS, Fondazione Giacomo Brodolini and Blackwell Publishing Ltd..