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This volume is about the plurality and complexity of modern urban public spaces. The authors move far beyond the nostalgia of traditional streets, squares and gardens to mobilize contemporary sociological knowledge based on the mediated relations between spatial morphology and everyday life in cities across several continents.

The European Union Reference Laboratory for Food Contact Materials (EURL-FCM) organised a proficiency test (PT) to assess the analytical capabilities of the EU National Reference Laboratories (NRLs) and Official Control Laboratories (OCLs) on the "temperature control" during migration tests by article filling at 70 °C for 2 h in food simulant D1 (ethanol 50 %, v/v), with the subsequent determination of the specific migration of 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene (cf. FCM No 500 in EU Reg. 10/2011). A total of 41 laboratories (25 NRLs and 16 OCLs) from 26 different countries reported results for the "temperature control" exercise. Thirty two laboratories (24 NRLs and 8 OCLs) submitted results for the "FCM No 500 quantification". For "temperature control", participants were requested to implement the learnings of the previous PTs when designing their experimental set up. Some general instructions were provided by the EURL-FCM. The test specimens consisted of a set of five 0.3 L polypropylene cups. Laboratories were requested to monitor the temperature of the food simulant inside one of the test specimens during the contact phase. Participants were requested to provide details of their operating procedure and to report their temperature readouts. The results show that 59 % of the 41 laboratories were able to maintain the temperature of the food simulant inside the tolerance range (70 °C ± 2 °C) during the entire migration contact time. This is a significant improvement compared to the results obtained in 2015. Another evaluation approach was investigated checking whether the mean temperature of the entire experiment falls in the range of 68-72 °C; 85 % of the laboratories performed successfully. For the "FCM quantification", the EURL-FCM confirmed the test items to be adequately homogeneous and stable. Laboratories had to develop an appropriate analytical method and to provide details. The assigned values of the migration of FCM No 500 were calculated as the robust mean and robust standard deviation of the results reported by the participants. The laboratory performance was expressed in terms of z and zeta scores in accordance with ISO 13528:2015. The outcome of this exercise was satisfactory for 80 % of the laboratories (24 out of 30). The remaining six laboratories had unsatisfactory z scores higher than 3. Although their quantification performance at 5 μg kg-1 level was unsatisfactory, this does not imply that their methods of analysis may be not be suitable for the determination at the legal specific migration limit (SML) of 600 μg kg-1. Laboratories were requested to estimate and report their measurement uncertainties. Half of them reported reasonable estimates. The EURL-FCM will organise a dedicated training to share best practices on the topic. The experimental information collected through the questionnaire further confirms the critical factors affecting the migration experiment: (1) covering/sealing the test specimen to reduce solvent losses, (2) reducing the filling time, (3) using calibrated thermometers/dataloggers and (4) avoiding pre-heating of the test specimen prior to the migration experiment.

The estimation of substitution and recombination rates can provide important insights into the molecular evolution of protein-coding sequences. Here, we present a new computational framework, called "CodABC," to jointly estimate recombination, substitution and synonymous and nonsynonymous rates from coding data. CodABC uses approximate Bayesian computation with and without regression adjustment and implements a variety of codon models, intracodon recombination, and longitudinal sampling. CodABC can provide accurate joint parameter estimates from recombining coding sequences, often outperforming maximum-likelihood methods based on more approximate models. In addition, CodABC allows for the inclusion of several nuisance parameters such as those representing codon frequencies, transition matrices, heterogeneity across sites or invariable sites. CodABC is freely available from http://code.google.com/p/codabc/, includes a GUI, extensive documentation and ready-to-use examples, and can run in parallel on multicore machines. ; This work was supported by the Spanish Government with the "Juan de la Cierva" fellowship JCI-2011-10452 to M.A., the European Research Council (ERC Grant Agreement No. 617457) to D.P., and Fundac¸~ao para a Ci^encia e a Tecnologia (FCT) (grant EXCL/BIA-ANM/0549/2012) to J.S.L. ; Peer reviewed

Chemical substances shall not migrate from food contact materials (FCM) at levels that are potentially harmful for the consumers. Each of the current analytical methods applied to verify the migration of substances from FCM covers only one or few substances. There is a very limited number of publications on the development of analytical methods allowing the simultaneous determination of several classes of FCM substances, and almost none of them reported methods entirely dedicated to the ones in the positive list of Commission Regulation (EU) No. 10/2011 for plastic FCMs. Therefore, a simple, sensitive and reliable multi-analyte method was developed for the analysis of FCM substances in food simulants. It employs an optimised liquid-liquid extraction with dichloromethane as extraction solvent in the presence of 10% m/v NaCl, followed by quantitative analysis with gas chromatography coupled to mass spectrometry (GC-MS). A combination of total ion chromatograms (TICs) and extracted ion chromatograms (EICs) was used. The optimisation and validation of the method have been carried out according to current international guidelines. Adequate sensitivity was demonstrated in the selected concentration ranges for most of the analytes, with limits of quantification (LOQs) at least three times lower than the legislative limit, when existing. The results showed that the method is sufficiently accurate for the majority of substances, with recoveries between 70 and 115% and relative standard deviations (RSDs) smaller than 20% at three concentration levels. The method was applied to the analysis of some FCM multilayers. The method allows, for the first time, the simultaneous quantification of 84 FCM substances in two of the official food simulants (A and C) at levels of a few ng g(−1). [Figure: see text] ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00216-020-02758-7) contains supplementary material, which is available to authorized users.

The outcome of a proficiency test (PT) organised by the European Union Reference Laboratory for Food Contact Materials (EURL-FCM) is presented. The PT was set up to assess the analytical performance of National Reference Laboratories (NRLs) and Official Control Laboratories (OCLs) in the determination of mass fractions of polyethylene terephthalate (PET) and polybutylene terephthalate (PBT) cyclic dimers and trimers in the official food simulant D1 containing ethanol and water (50:50 v/v). The EURL-FCM had developed and validated an analytical method based on HPLC-UV to monitor the homogeneity and stability of the target oligomers in the PT test items and to determine the respective assigned values, as prescribed in ISO 17043, 2010ISO 17043, 2010. The standard operating procedure of the method was provided to the participants and could be used instead of their own routine methods. Laboratory results were rated using z, z' and ζ scores in accordance with ISO 13528, 2015. The standard deviation for proficiency assessment, σ(pt), was set to 20 % of the respective assigned value, for all the four studied oligomers, based on the perception of experts. A total of 36 participants from 26 countries have registered to the exercise. They received two test items. Solution 1 consisted of food simulant D1 fortified with a known mass fraction of the four oligomers, while Solution 2 was obtained by a migration experiment with PET bottles and food simulant D1 and further fortification of the resulting solution with the four oligomers. The majority of the participating laboratories presented satisfactory results for the four PET and PBT oligomers. For the analysis of Solution 1, 79–88 % of the participants obtained |z (or z')-scores| below 2, while the satisfactory performances ranged from 71 to 85 % for Solution 2. This PT has been organised for the first time at EU level for the analysis of polyester oligomers and confirms that most of the NRLs are able to monitor properly these oligomers in the frame of Regulation (EU) No ...

13 pages, 4 figures, 3 tables ; Background Molecular tools may help to uncover closely related and still diverging species from a wide variety of taxa and provide insight into the mechanisms, pace and geography of marine speciation. There is a certain controversy on the phylogeography and speciation modes of species-groups with an Eastern Atlantic-Western Indian Ocean distribution, with previous studies suggesting that older events (Miocene) and/or more recent (Pleistocene) oceanographic processes could have influenced the phylogeny of marine taxa. The spiny lobster genus Palinurus allows for testing among speciation hypotheses, since it has a particular distribution with two groups of three species each in the Northeastern Atlantic (P. elephas, P. mauritanicus and P. charlestoni) and Southeastern Atlantic and Southwestern Indian Oceans (P. gilchristi, P. delagoae and P. barbarae). In the present study, we obtain a more complete understanding of the phylogenetic relationships among these species through a combined dataset with both nuclear and mitochondrial markers, by testing alternative hypotheses on both the mutation rate and tree topology under the recently developed approximate Bayesian computation (ABC) methods. Results Our analyses support a North-to-South speciation pattern in Palinurus with all the South-African species forming a monophyletic clade nested within the Northern Hemisphere species. Coalescent-based ABC methods allowed us to reject the previously proposed hypothesis of a Middle Miocene speciation event related with the closure of the Tethyan Seaway. Instead, divergence times obtained for Palinurus species using the combined mtDNA-microsatellite dataset and standard mutation rates for mtDNA agree with known glaciation-related processes occurring during the last 2 my. Conclusion The Palinurus speciation pattern is a typical example of a series of rapid speciation events occurring within a group, with very short branches separating different species. Our results support the hypothesis that recent climate change-related oceanographic processes have influenced the phylogeny of marine taxa, with most Palinurus species originating during the last two million years. The present study highlights the value of new coalescent-based statistical methods such as ABC for testing different speciation hypotheses using molecular data. ; This work was supported by a pre-doctoral fellowship awarded by the Autonomous Government of Catalonia to FP (2006FIC-00082). Joao Lopes is funded by EPSRC grant EP/C533550/1 awarded to MAB. Research was funded by projects CGL2006-13423 and CTM2007-66635 from the Ministerio de Educación y Ciencia. The authors are part of the research group 2009SGR-636, 2009SGR-655 and 2009SGR-1364 of the Generalitat de Catalunya. FP acknowledges EU-Synthesys grant (GB-TAF-4474). ; Peer reviewed

A HPLC-UV/FLD method was validated for the quantification of six polyethylene terephthalate (PET) and four polybutylene terephthalate (PBT) oligomers. PBT oligomers are EU regulated, while the PET ones are considered non-intentionally added substances (NIAS). LOQs were higher than 0.4 and 3.5 μg kg(−1) for the simulants and in the polymer extracts, respectively. Recoveries ranged from 95 to 114 % with RSDs below 12%. Migration testing of PBT and polypropylene coffee capsules were performed with H(2)O and simulant C, and extracts were obtained with accelerated solvent extraction (ASE). For the latter legislative limits weren't surpassed. As no migration limits are existing for the analytes, both EFSA's toxicological threshold of concern (TTC) and sum of oligomers approaches were applied. The majority of oligomers were below the TTC (90 µg/person/day), but the limit value of 50 µg/kg food was surpassed for some capsules, which indicates a significant intake in both single and multiple consumption.

A simple and fast method was developed for the simultaneous determination of 75 plastic food contact material (FCM) in liquid food simulants, at levels of a few ng g −1 . The method employs an optimised salt-assisted liquid–liquid extraction for all EU-regulated ethanol/H 2 O food simulants, in the presence of 10% NaCl (simulants A and C) or 5% NaCl (simulant D1), and dichloromethane as the extracting solvent. Gas chromatography with triple-quad MS operating in multiple reaction monitoring acquisition was used, applying isotope dilution with selected deuterated compounds. Adequate sensitivity was demonstrated for all analytes. The results also showed sufficient accuracy for the majority of substances, with recoveries of 70–120% and repeatability (expressed as relative standard deviations, RSDs) smaller than 15%. The method was applied to the analysis of FCM multilayer items after undergoing migration testing according to the specifications of the current EU legislation in force.

9 pages.-- PACS numbers: 02.70.Rr, 64.60.Cn, 75.10.Hk, 05.10.Ln.-- Final full-text version of the paper available at: http://dx.doi.org/10.1103/PhysRevE.74.046702. ; We propose a recursive procedure to estimate the microcanonical density of states in multicanonical Monte Carlo simulations which relies only on measurements of moments of the energy distribution, avoiding entirely the need for energy histograms. This method yields directly a piecewise analytical approximation to the microcanonical inverse temperature beta(E) and allows improved control over the statistics and efficiency of the simulations. We demonstrate its utility in connection with recently proposed schemes for improving the efficiency of multicanonical sampling, either with adjustment of the asymptotic energy distribution or with the replacement of single spin flip dynamics with collective updates. ; This work was supported by FCT (Portugal) and the European Union, through POCTI (QCA III). Two of the authors, J.V.L. and M.D.C., were supported by FCT Grant Nos. SFRH/BD/1261/2000 and SFRH/BD/ 7003/2001, respectively. R.T. was supported by the Spanish Government and FEDER (EU) through Project Nos. FIS2004-5073, FIS2004-953.

8 pages, 7 figures.-- PACS nrs.: 05.50.+q, 64.60.Cn, 05.70.Jk.-- ArXiv pre-print available: http://lanl.arxiv.org/abs/cond-mat/0402138 ; We present an exact solution of a one-dimensional Ising chain with both nearest-neighbor and random long-range interactions. Not surprisingly, the solution confirms the mean-field character of the transition. This solution also predicts the finite-size scaling that we observe in numerical simulations. ; This work was financed by FCT (Portugal) and the European Union, through POCTI (QCA III). One of the authors (J.V.L.) was supported by FCT grant (Portugal) No. SFRH/BD/1261/2000 and another author (R.T.) by MCYT (Spain) and FEDER through project Nos. BFM2000-1108 and BFM2001-0341-C02-01. ; Peer reviewed

International audience ; Microgrids comprise Low Voltage distribution systems with distributed energy sources, such as micro-turbines, fuel cells, PVs, etc., together with storage devices, i.e. flywheels, energy capacitors and batteries, and controllable loads, offering considerable control capabilities over the network operation. These systems are interconnected to the Medium Voltage Distribution network, but they can be also operated isolated from the main grid, in case of faults in the upstream network. From the customer point of view, Microgrids provide both thermal and electricity needs, and in addition enhance local reliability, reduce emissions, improve power quality by supporting voltage and reducing voltage dips, and potentially lower costs of energy supply. This paper outlines selected research findings of the EU funded MICROGRIDS project (Contract ENK-CT-2002-00610). These include: • Development and enhancement of Microsource controllers to support frequency and voltage based on droops. Application of software agents for secondary control. • Development of the Microgrid Central Controller (MGCC). Economic Scheduling functions have been developed and integrated in a software package able to simulate the capabilities of the MGCC to place bids to the market operator under various policies and to evaluate the resulting environmental benefits. • Analysis of the communication requirements of the Microgrids control architecture • Investigation of alternative market designs for trading energy and ancillary services within a Microgrid. Development of methods for the quantification of reliability and loss reduction. • Initial measurements from an actual LV installation.

International audience ; Microgrids comprise Low Voltage distribution systems with distributed energy sources, such as micro-turbines, fuel cells, PVs, etc., together with storage devices, i.e. flywheels, energy capacitors and batteries, and controllable loads, offering considerable control capabilities over the network operation. These systems are interconnected to the Medium Voltage Distribution network, but they can be also operated isolated from the main grid, in case of faults in the upstream network. From the customer point of view, Microgrids provide both thermal and electricity needs, and in addition enhance local reliability, reduce emissions, improve power quality by supporting voltage and reducing voltage dips, and potentially lower costs of energy supply. This paper outlines selected research findings of the EU funded MICROGRIDS project (Contract ENK-CT-2002-00610). These include: • Development and enhancement of Microsource controllers to support frequency and voltage based on droops. Application of software agents for secondary control. • Development of the Microgrid Central Controller (MGCC). Economic Scheduling functions have been developed and integrated in a software package able to simulate the capabilities of the MGCC to place bids to the market operator under various policies and to evaluate the resulting environmental benefits. • Analysis of the communication requirements of the Microgrids control architecture • Investigation of alternative market designs for trading energy and ancillary services within a Microgrid. Development of methods for the quantification of reliability and loss reduction. • Initial measurements from an actual LV installation.