How do people get to the railway station : a spatial analysis of the first and the last part of multimodal trips

The quality of transport networks does not only depend on the quality of the individual links and nodes, but also on the way these nodes and linksfunction in the context of (multimodal)networks. In the present paper we focus on multimodal trips where the railways are the maintransport mode. We discuss detour and frequency problems related to multimodal transportchains. Local accessibility of railway stations is an important determinant of railway use in the Netherlands. We find that the propensity to make useof rail services of people living in the ring between 500 to 1000 meter from a railway station is about 20% lower than of people living at most 500meter away from railway stations. At distances between 1 .O and 3.5 km the distance decay effect is about 30%: and above this distance it may reachvalues up to 50%. Non-motorized transport modes are dominant at both the home-end and the Activity-end. A rather unique feature of the home-end accessmode is the high share of the bicycle. More than one out of every three passengers uses the bike on the trip from home to station. At the activity-endthe share of the bike is much smaller, because of the asymmetry in the supply of this transport mode in the home versus the activity-end. This explainsthe dominant position of walking as the access mode at the activity-end. Implications are discussed for physical planning and the need for facilitiesnear railway stations

IT development in the local setting - an architectural perspective

The objective of this article is to describe some relevant undertakings related to the introduction of local communication networks in residential areas in Sweden and to broaden the discussion on the ongoing IT development and its influence on local settings and living. A further objective is to discuss how current and expected changes might influence research in architecture and its relevance for the architectural profession

Veertig jaar epidemiologie aan de Erasmus Universiteit 1969-2009

Waarschijnlijk telt geen land ter wereld per hoofd van de bevolking zoveel epidemiologen als Nederland. De Nederlandse Vereniging van Epidemiologen is een van de grootste in Europa. Elke maand verschijnen in de beste internationale wetenschappelijke tijdschriften resultaten van Nederlands epidemiologisch onderzoek. En het zijn artikelen die ertoe doen. In de top 25 van meest geciteerde Nederlands onderzoekers zijn er alleen al zes gelieerd aan het ERGO-onderzoek: een cohort van inmiddels ruim 15.000 Rotterdammers dat nu al bijna 20 jaar loopt. Om kort te gaan: epidemiologie is hot in Holland. Deze bundel bevat afscheidsredes en oraties uit de afgelopen veertig jaar, Tot slot bevat dit boek een opsomming van promovendi die vanuit de afdeling Epidemiologie hun proefschrift verdedigden aan de Erasmus Universiteit, en van alle medewerkers, oud-medewerkers en gasten met een formele aanstelling bij de afdeling Epidemiologie

Deconjugation Kinetics of Glucuronidated Phase II Flavonoid Metabolites by B-glucuronidase from Neutrophils

Flavonoids are inactivated by phase II metabolism and occur in the body as glucuronides. Mammalian ß-glucuronidase released from neutrophils at inflammatory sites may be able to deconjugate and thus activate flavonoid glucuronides. We have studied deconjugation kinetics and pH optimum for four sources of ß-glucuronidase (human neutrophil, human recombinant, myeloid PLB-985 cells, Helix pomatia) with five flavonoid glucuronides (quercetin-3-glucuronide, quercetin-3'-glucuronide, quercetin-4'-glucuronide, quercetin-7-glucuronide, 3'-methylquercetin-3-glucuronide), 4-methylumbelliferyl-ß-D-glucuronide, and para-nitrophenol-glucuronide. All substrate-enzyme combinations tested exhibited first order kinetics. The optimum pH for hydrolysis was between 3.5-5, with appreciable hydrolysis activities up to pH 5.5. At pH 4, the Km ranged 44-fold from 22 µM for quercetin-4'-glucuronide with Helix pomatia ß-glucuronidase, to 981 µM for para-nitrophenol-glucuronide with recombinant ß-glucuronidase. Vmax (range: 0.735-24.012 µmol·min-1·unit-1 [1 unit is defined as the release of 1 µM 4-methylumbelliferyl-ß-D-glucuronide per min]) and the reaction rate constants at low substrate concentrations (k) (range: 0.002-0.062 min-1·(unit/L)-1 were similar for all substrates-enzyme combinations tested. In conclusion, we show that ß-glucuronidase from four different sources, including human neutrophils, is able to deconjugate flavonoid glucuronides and non-flavonoid substrates at fairly similar kinetic rates. At inflammatory sites in vivo the pH, neutrophil and flavonoid glucuronide concentrations seem favorable for deconjugation. However, it remains to be confirmed whether this is actually the case

Expectations about Fertility and Field of Study among Adolescents: A Case of Self-selection?

In recent studies on the association between education and fertility, increased attention has been paid to the field of study. Women who studied in traditionally more “feminine” fields, like care, teaching, and health, were found to have their children earlier and to have more children than other women. A point of debate in this literature is on the causal direction of this relationship. Does the field of study change the attitudes towards family formation, or do young adults with stronger family-life attitudes self-select into educational fields that emphasize care, teaching, and health? Or do both field of study preferences and family-life attitudes arise before actual choices in these domains are made?We contribute to this debate by examining the relationship between fertility expectations and expected fields of study and occupation among 14-17 year-old adolescents. We use data collected in 2005 from 1500 Dutch adolescents and Structural Equation Modelling (SEM) to examine the associations between expected field of study and occupation and fertility expectations. Our results show that expectations concerning fertility and field of study are already interrelated during secondary education. Both female and male adolescents who expect to pursue studies in fields that focus on care and social interaction (like health care, teaching etc.) are less likely to expect to remain childless. This holds equally for girls and boys. In addition, girls who more strongly aspire to an occupation in which communication skills are important also expect to have more children. We did not find any relationship between expectations of pursuing a communicative field of study and occupation and expectations of earlier parenthood.In addition, among boys, we find that the greater their expectation of opting for an economics, a technical, or a communicative field of study, the less likely they were to expect to remain childless. Boys who expected to study in the economic field also expect to have their first child earlier, but boys expecting to pursue a technical course of studies expect to enter parenthood later. We also found that those who expect to pursue cultural studies are more likely to have a preference for no children, or if they do want children, to have them later in life.Overall, our findings suggest that the processes of elective affinity between the communicative fields of study and work on the one hand and fertility on the other hand are more or less comparable for boys and girls. With respect to the other domains, we find, apart from the gender differences in the relation between fields of study and childlessness, hardly or no gender differences in the expected timing of parenthood and the number of children. The genders do differ in their level of preference for communicative and economics-related fields of study and occupation, but if they do have the same preference, the association with fertility expectations is more or less similar

Downregulation of Fzd6 and Cthrc1 and upregulation of olfactory receptors and protocadherins by dietary beta-carotene in lungs of Bcmo1-/- mice.

An ongoing controversy exists on beneficial versus harmful effects of high beta-carotene (BC) intake, especially for the lung. To elucidate potential mechanisms, we studied effects of BC on lung gene expression. We used a beta-carotene 15,15'-monooxygenase 1 (Bcmo1) knockout mouse (Bcmo1-/-) model, unable to convert BC to retinoids, and wild-type mice (Bcmo1+/+) mice to dissect the effects of intact BC from effects of BC metabolites. As expected, BC supplementation resulted in a higher BC accumulation in lungs of Bcmo1-/- mice than in lungs of Bcmo1+/+ mice. Whole mouse genome transcriptome analysis on lung tissue revealed that more genes were regulated in Bcmo1-/- mice than Bcmo1+/+ mice upon BC supplementation. Frizzled homolog 6 (Fzd6) and collagen triple helix repeat containing 1 (Cthrc1) were significantly downregulated (fold changes -2.99 and -2.60, respectively, false discovery rate <0.05) by BC in Bcmo1-/-. Moreover, many olfactory receptors and many members of the protocadherin family were upregulated. Since both olfactory receptors and protocadherins have an important function in sensory nerves and Fzd6 and Cthrc1 are important in stem cell development, we hypothesize that BC might have an effect on the highly innervated pulmonary neuroendocrine cell (PNEC) cluster. PNECs are highly associated with sensory nerves and are important cells in the control of stem cells. A role for BC in the innervated PNEC cluster might be of particular importance in smoke-induced carcinogenesis since PNEC-derived lung cancer is highly associated with tobacco smoke