Verspreiding inlaatwater in beeld met nieuwe tracer

Inlaatwater heeft in de polder Quarles van Ufford zelfs in een droge periode geen invloed op de waterkwaliteit van kleine landbouwsloten. Dat blijkt uit metingen van de concentratie gadolinium, die zijn uitgevoerd voor het project Monitoring Stroomgebieden. Hiermee komt voor dit gebied een einde aan de twijfel over de invloed van inlaatwater op de oppervlaktewaterkwaliteit en is er meer duidelijkheid over de belasting vanuit de landbouw

Het recht is intellectueel buitengewoon interessant, maar het gaat om de functie die het vervult in de samenleving. Interview met prof.mr. P. Van Schilfgaarde

FdR – Publicaties zonder aanstelling Universiteit Leide

Get it together! Synergistic effects of causal and effectual decision-making logics on venture performance

Entrepreneurs rely on different decision-making logics when starting new ventures, including causal and effectual reasoning. Extant research suggests that venture performance is positively associated with both causal business planning and effectual action-orientation, but studies have not yet tested the synergistic potential of these two logics. We contribute to the debate on entrepreneurial decision making by exploring the interrelationship between causation and effectuation, detailing their main and interactive effects on venture performance. Using survey data collected on 1,453 entrepreneurs residing in 25 countries, we find that ventures benefit from using these two entrepreneurial logics in tandem

Haplotype block structure is conserved across mammals

Genetic variation in genomes is organized in haplotype blocks, and species-specific block structure is defined by differential contribution of population history effects in combination with mutation and recombination events. Haplotype maps characterize the common patterns of linkage disequilibrium in populations and have important applications in the design and interpretation of genetic experiments. Although evolutionary processes are known to drive the selection of individual polymorphisms, their effect on haplotype block structure dynamics has not been shown. Here, we present a high-resolution haplotype map for a 5-megabase genomic region in the rat and compare it with the orthologous human and mouse segments. Although the size and fine structure of haplotype blocks are species dependent, there is a significant interspecies overlap in structure and a tendency for blocks to encompass complete genes. Extending these findings to the complete human genome using haplotype map phase I data reveals that linkage disequilibrium values are significantly higher for equally spaced positions in genic regions, including promoters, as compared to intergenic regions, indicating that a selective mechanism exists to maintain combinations of alleles within potentially interacting coding and regulatory regions. Although this characteristic may complicate the identification of causal polymorphisms underlying phenotypic traits, conservation of haplotype structure may be employed for the identification and characterization of functionally important genomic regions

Entrepreneurship and Role Models

In the media role models are increasingly being acknowledged as an influential factor in explaining the reasons for the choice of occupation and career. Various conceptual studies have proposed links between role models and entrepreneurial intentions. However, empirical research aimed at establishing the importance of role models for (nascent) entrepreneurs is scarce. Knowledge of the presence of entrepreneurial role models, their specific functions and characteristics is therefore limited. Our explorative empirical study is a first step towards filling this gap. Our study is based on the outcomes of a questionnaire completed by a representative sample of 292 entrepreneurs in three major Dutch cities - entrepreneurs who have recently started up a business in the retail, hotel and restaurant sectors, business services and other services. We provide indications of the presence and importance of entrepreneurial role models, the function of these role models, the similarity between the entrepreneur and the role model, and the strength of their relationship