Commuting in multinodal urban systems: An empirical comparison of three alternative models

The paper analyses whether the basic monocentric model of urban structure and commuting explains actual commuting in Europe, i.e. the Netherlands. As in the United States much wasteful commuting is established. The basic model has a low degree of explanatory power. In order to get more in line with actual commuting, the paper elaborates two alternatives to the basic model. Besides a decon-centrated model, a cross-traffic model is developed. Particularly the latter is quite successful in explaining actual commuting. The paper pleads for endo-geni-zing employment and stresses heterogeneity in labour demand and supply.

ICT and Productivity - relations and dynamics in a spatial context

The strong emergence of ICT in the past decades was accompanied by much research on the potential productivity boosting qualities of ICT: high productivity growth was expected. However, empirical evidence on the productivity impact of ICT stayed behind: the Solow paradox. Since then analytical steps were made by using alternative indicators for both ICT adoption and productivity and including longer time periods, distinctions in types of economic activities and adding micro level and firm specific characteristics like size, age, and intensity of innovation. Moreover, ICT was linked to network relations including externalities. These adaptations led to outcomes in favour of a positive relation between the use of ICT and productivity. However, most convincing in this debate was the finding that the effects of ICT on economic performance should be analysed from a perspective which, besides ICT, includes changes in knowledge and organisations. Knowledge is defined here broadly and includes both codified and tacit knowledge. In this paper we focus on the trinity ‘ICT, knowledge and organization’ and add the regional dimension to this. Based on economic literature our hypothesis is that regions where firms increasingly use ICT show a stronger growth of added value and productivity. This positive relationship is, however, co-determined by changes in the broadly defined knowledge level. The use of ICT by firms is analysed at different levels of urbanism in the Netherlands. Most central is the distinction between the metropolitan Randstad, the intermediate zone and the national periphery. By this regional distinction the debate on the centrifugal and centripetal effects of ICT (the death of distance) is included. The empirical measurement as such is based on the low spatial scale of 496 municipalities.

Identification and Validation Model for Informative Liquid Biopsy-Based microRNA Biomarkers:Insights from Germ Cell Tumor In Vitro, In Vivo and Patient-Derived Data

Liquid biopsy-based biomarkers, such as microRNAs, represent valuable tools for patient management, but often do not make it to integration in the clinic. We aim to explore issues impeding this transition, in the setting of germ cell tumors, for which novel biomarkers are needed. We describe a model for identifying and validating clinically relevant microRNAs for germ cell tumor patients, using both in vitro, in vivo (mouse model) and patient-derived data. Initial wide screening of candidate microRNAs is performed, followed by targeted profiling of potentially relevant biomarkers. We demonstrate the relevance of appropriate (negative) controls, experimental conditions (proliferation), and issues related to sample origin (serum, plasma, cerebral spinal fluid) and pre-analytical variables (hemolysis, contaminants, temperature), all of which could interfere with liquid biopsy-based studies and their conclusions. Finally, we show the value of our identification model in a specific scenario, contradicting the presumed role of miR-375 as marker of teratoma histology in liquid biopsy setting. Our findings indicate other putative microRNAs (miR-885-5p, miR-448 and miR-197-3p) fulfilling this clinical need. The identification model is informative to identify the best candidate microRNAs to pursue in a clinical setting

Psychopathic Traits of Dutch Adolescents in Residential Care: Identifying Subgroups

The present study examined whether a sample of 214 (52.8% male, M age = 15.76, SD = 1.29) institutionalized adolescents could be classified into subgroups based on psychopathic traits. Confirmatory Factor Analyses revealed a relationship between the subscales of the Youth Psychopathic traits Inventory (YPI) and the three latent constructs of the original model on which it is based. Latent Class Analyses showed that adolescents showing psychopathic traits could be classified into three subgroups. The first group showed low scores on the grandiose/manipulative dimension, the callous/unemotional dimension, and the impulsive/irresponsible dimension (normal group). The second group scored moderate on the grandiose/manipulative dimension and the callous/unemotional dimension and high on the impulsive/irresponsible dimension (impulsive, non-psychopathic-like group). The third group scored high on all three dimensions (psychopathy-like group). The findings revealed that the impulsive, non-psychopathic like group scored significantly higher on internalizing problem behavior compared to the normal group, while the psychopathy-like and the impulsive, non-psychopathic-like group both scored higher on externalizing problem behavior compared to the normal group. Based on a self-report delinquency measure, it appeared that the psychopathy-like group had the highest delinquency rates, except for vandalism. Both the impulsive and psychopathy-like group had the highest scores on the use of soft drugs

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

Genetic associations at 53 loci highlight cell types and biological pathways relevant for kidney function.

Reduced glomerular filtration rate defines chronic kidney disease and is associated with cardiovascular and all-cause mortality. We conducted a meta-analysis of genome-wide association studies for estimated glomerular filtration rate (eGFR), combining data across 133,413 individuals with replication in up to 42,166 individuals. We identify 24 new and confirm 29 previously identified loci. Of these 53 loci, 19 associate with eGFR among individuals with diabetes. Using bioinformatics, we show that identified genes at eGFR loci are enriched for expression in kidney tissues and in pathways relevant for kidney development and transmembrane transporter activity, kidney structure, and regulation of glucose metabolism. Chromatin state mapping and DNase I hypersensitivity analyses across adult tissues demonstrate preferential mapping of associated variants to regulatory regions in kidney but not extra-renal tissues. These findings suggest that genetic determinants of eGFR are mediated largely through direct effects within the kidney and highlight important cell types and biological pathways

Changing Urban Systems: An Empirical Analysis at Two Spatial Levels

VAN DER LAAN L. (1998) Changing urban systems, an empirical analysis at two spatial levels, Reg. Studies 32, 235-247. Changes in the urban system are increasingly caused by the interdependency of the local and regional level. This requires a framework which incorporates the processes of both levels. On the basis of an empirical analysis of commuting patterns and urban labour markets in the Netherlands, a framework is proposed which relates changes in the urban system to changes in the regional employment structure. VAN DER LAAN L. (1998) Transformer les systemes urbains: une analyse empirique a deux niveaux spatiaux, Reg. Studies 32, 235-247. La transformation du systeme urbain remonte de plus en plus a l'interdependance des niveaux local et regional. Cela laisse supposer un cadre qui comporte les processus des deux niveaux. A partir d'une analyse empirique de la structure des migrations quotidiennes et des marches de l'emploi urbains aux Pays-Bas, on propose un cadre qui rapporte la transformation du systeme urbain a l'evolution de la structure de l'emploi regional. VAN DER LAAN L. (1998) Stadtsysteme im Wandel: eine empirische Analyse auf zwei raumlichen Ebenen, Reg. Studies 32, 235-247. Veranderungen im stadtischen System werden zunehmend durch die gegenseitige Abhangigkeit der Lokalund der Regionalebene verursacht. Es drangt sich dabei der Gedanke auf, sie durch eine Grundstruktur zu ersetzen, welche die Vorgange beider Ebenen in sich vereinigt. Unter Bezugnahme auf eine empirische Analyse von Pendlermustern und stadtischen Arbeitsmarkten in den Niederlanden wird eine Rahmenstruktur vorgeschlagen, die Wandel im Stadtsystem mit Veranderungen in der Regionalstruktur des Erwerbslebens in Beziehung setzt.Urban System, Network, Commuting, Labour Market, Multi-NODALITY,