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Human behaviour follows a 24-h rhythm and is known to be governed by the individual chronotypes. Due to the widespread use of technology in our daily lives, it is possible to record the activities of individuals through their different digital traces. In the present study we utilise a large mobile phone communication dataset containing time stamps of calls and text messages to study the circadian rhythms of anonymous users in a European country. After removing the effect of the synchronization of East-West sun progression with the calling activity, we used two closely related approaches to heuristically compute the chronotypes of the individuals in the dataset, to identify them as morning persons or "larks" and evening persons or "owls". Using the computed chronotypes we showed how the chronotype is largely dependent on age with younger cohorts being more likely to be owls than older cohorts. Moreover, our analysis showed how on average females have distinctly different chronotypes from males. Younger females are more larkish than males while older females are more owlish. Finally, we also studied the period of low calling activity for each of the users which is considered as a marker of their sleep period during the night. We found that while "extreme larks" tend to sleep more than "extreme owls" on the weekends, we do not observe much variation between them on weekdays. In addition, we have observed that women tend to sleep even less than males on weekdays while there is not much difference between them on the weekends. [ABSTRACT FROM AUTHOR]

In entry-exit gas markets as they are currently implemented in Europe, network constraints do not affect market interaction beyond the technical capacities determined by the TSO that restrict the quantities individual firms can trade at the market. It is an up to now unanswered question to what extent existing network capacity remains unused in an entry-exit design and to what extent feasible adjustments of the market design could alleviate inefficiencies. In this paper, we offer a four-level modeling framework that is capable of analyzing these issues and provide some first results on the model structure. In order to decouple gas trading from network congestion management, the TSO is required to determine technical capacities and corresponding booking fees at every entry and exit node up front. Firms book those capacities, which gives them the right to charge or discharge an amount of gas at a certain node up to this capacity in every scenario. Beyond these technical capacities and the resulting bookings, gas trade is unaffected by network constraints. The technical capacities have to ensure that transportation of traded quantities is always feasible. We assume that the TSO is regulated and determines technical capacities, fees, and transportation costs under a welfare objective. As a first step we moreover assume perfect competition among gas traders and show that the booking and nomination decisions can be analyzed in a single level. We prove that this aggregated model has a unique solution. We also show that the TSO's decisions can be subsumed in one level as well. If so, the model boils down to a mixed-integer nonlinear bilevel problem with robust aspects. In addition, we provide a first-best benchmark that allows to assess welfare losses that occur in an entry-exit system. Our approach provides a generic framework to analyze various aspects in the context of semi-liberalized gas markets. Therefore, we finally discuss and provide guidance on how to include several important aspects into the approach, such as network and production capacity investment, uncertain data, market power, and intra-day trading. [ABSTRACT FROM AUTHOR]

Purpose: To analyse the impact of overweight on HRQoL in a European sample of children and adolescents. Methods: Analyses were conducted using data on 17,159 children and adolescents aged 8-18 from 10 European countries (Germany, Spain, France, Netherlands, Austria, United Kingdom, Switzerland, Hungary, Czech Republic and Poland) participating in the KIDSCREEN Health Interview Survey. In the studied sample ( N = 13,041), there were slightly more girls (52.6%) than boys (47.4%). Gender- and age-specific cut-offs of Cole et al. (BMJ 320:1240, 2000) were used to define overweight and obesity. The two groups were collapsed into one 'overweight' category. HRQoL was assessed on 10 dimensions using the KIDSCREEN-52. Univariate analysis of covariance (ANCOVA) was performed for group comparisons (normal weight vs. overweight). Partial eta squared (η) was used as a measure of effect strength. Results: Overall, 14.2% ( N = 1,849) of the sample was overweight, with prevalence rates ranging between 9.4% in France and 17.6% in Spain. Across all countries, overweight children and adolescents had lower mean HRQoL scores than normal weight children and adolescents. The strongest HRQoL impairments emerged on the physical well-being (η = 0.012) and self-perception dimensions (η = 0.021), both P < 0.001. Conclusions: This is one of the first studies comparing the impact of HRQoL at European level using a generic and internationally valid HRQoL instrument, and the results show that, irrespective of national background, overweight children and adolescents are significantly impaired on their HRQoL, in particular on the physical well-being and the self-perception domain. [ABSTRACT FROM AUTHOR]

Heat flow variations with depth in Europe can be explained by a model of surface temperature changes >10°C. New heat flow map of Europe is based on updated database of uncorrected heat flow values to which paleoclimatic correction is applied across the continent. Correction is depth dependent due to a diffusive thermal transfer of the surface temperature forcing of which glacial-interglacial history has the largest impact. It is obvious that large part of the uncorrected heat flow values in the existing heat flow databases from wells as shallow as few hundreds of meters is underestimated. This explains some very low uncorrected heat flow values 20-30 mW/m in the shields and shallow basin areas of the craton. Also, heat flow values in other areas including orogenic belts are likely underestimated. Based on the uncorrected and corrected heat flow maps using 5 km × 5 km grid, we have calculated average heat flow values (uncorrected heat flow: 56.0 mW/m; SD 20.3 mW/m vs. corrected heat flow: 63.2 mW/m; SD 19.6 m/Wm) and heat loss for the continental part. Total heat loss is 928 E09 W for the uncorrected values versus corrected 1050 E09 W. [ABSTRACT FROM AUTHOR]