Gas signatures of Herbig Ae/Be disks probed with Herschel SPIRE spectroscopy

Herbig Ae/Be objects, like their lower mass counterparts T Tauri stars, are seen to form a stable circumstellar disk which is initially gas-rich and could ultimately form a planetary system. We present Herschel SPIRE 460-1540 GHz spectra of five targets out of a sample of 13 young disk sources, showing line detections mainly due to warm CO gas.Comment: to be published in proceedings of IAU symposium 299 (Victoria, BC, Canada, June 2013

The relative age effect reversal among the National Hockey League elite

Like many sports in adolescence, junior hockey is organized by age groups. Typically, players born after December 31st are placed in the subsequent age cohort and as a result, will have an age advantage over those players born closer to the end of the year. While this relative age effect (RAE) has been well-established in junior hockey and other professional sports, the long-term impact of this phenomenon is not well understood. Using roster data on North American National Hockey League (NHL) players from the 2008-2009 season to the 2015-2016 season, we document a RAE reversal—players born in the last quarter of the year (October-December) score more and command higher salaries than those born in the first quarter of the year. This reversal is even more pronounced among the NHL “elite.” We find that among players in the 90th percentile of scoring, those born in the last quarter of the year score about 9 more points per season than those born in the first quarter. Likewise, elite players in the 90th percentile of salary who are born in the last quarter of the year earn 51% more pay than players born at the start of the year. Surprisingly, compared to players at the lower end of the performance distribution, the RAE reversal is about three to four times greater among elite players

Eating and mealtime behaviors in patients with autism spectrum disorder: Current perspectives

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impaired social and communication skills and repetitive and restrictive behaviors. Children and adolescents with ASD are more likely to present feeding problems than their typically developing peers are. The present narrative review of literature aims to highlight the most recent evidence about epidemiology and presentations of eating and mealtime behavioral abnormalities in ASD from infancy to adolescence. Abnormalities in breastfeeding and acceptance of complementary foods have been described by most of the studies evaluating ASD early feeding history. Among the various eating and mealtime behaviors identified in ASD children and adolescents, the most common was food selectivity. The present review also provides brief overviews of the various aspects of food that may influence food acceptance by ASD patients and of the correlation between eating problems and ASD core symptoms, as well as with cognitive level, language skills, and family environment. However, studies evaluating eating problems in ASD children and adolescents are very heterogeneous and they show methodological differences. Moreover, the absence of unique definitions of eating and mealtime behaviors in ASD further limits the comparability of studies

Porous medium equation with nonlocal pressure

We provide a rather complete description of the results obtained so far on the nonlinear diffusion equation $u_t=\nabla\cdot (u^{m-1}\nabla (-\Delta)^{-s}u)$, which describes a flow through a porous medium driven by a nonlocal pressure. We consider constant parameters $m>1$ and $0<s<1$, we assume that the solutions are non-negative, and the problem is posed in the whole space. We present a theory of existence of solutions, results on uniqueness, and relation to other models. As new results of this paper, we prove the existence of self-similar solutions in the range when $N=1$ and $m>2$, and the asymptotic behavior of solutions when $N=1$. The cases $m = 1$ and $m = 2$ were rather well known.Comment: 24 pages, 2 figure

Epidemiological and virological assessment of influenza activity in Apulia, Italy, during the seasons 2004 - 2005 and 2005 - 2006.

This study evaluated the impact of influenza and vaccination coverage in Apulia, Italy, during the 2004–2005 and 2005–2006 seasons, using epidemiological and virological surveillance data collected through the Italian Net of Surveillance of Influenza (InfluNet) organized by the Superior Institute of Health (ISS) and the Inter-University Centre of Research on Influenza (CIRI). Vaccination coverage was calculated from the number of doses administered to individuals aged ≤ 65 years. Sentinel physicians reported weekly influenza-like illness (ILI) and acute respiratory illness (ARI) occurrences among patients. Influenza viruses were isolated and identified by cell culture on Madin-Darby Canine Kidney cells and polymerase chain reaction techniques. Vaccination coverage reached 72.7% and 77.0% during the 2004–2005 and 2005–2006 seasons, respectively. Incidence of ILI was higher during the 2004–2005 season compared with the 2005–2006 season, whereas the incidence ARI appeared to show a more constant trend. Incidence rates for ILI and ARI were higher in the 0 − 14-year age group. The increase in vaccination coverage and implementation of a network of epidemiological and virological surveillance are fundamental for the control and prevention of influenza

A numerical approach to copolymers at selective interfaces

We consider a model of a random copolymer at a selective interface which undergoes a localization/delocalization transition. In spite of the several rigorous results available for this model, the theoretical characterization of the phase transition has remained elusive and there is still no agreement about several important issues, for example the behavior of the polymer near the phase transition line. From a rigorous viewpoint non coinciding upper and lower bounds on the critical line are known. In this paper we combine numerical computations with rigorous arguments to get to a better understanding of the phase diagram. Our main results include: - Various numerical observations that suggest that the critical line lies strictly in between the two bounds. - A rigorous statistical test based on concentration inequalities and super-additivity, for determining whether a given point of the phase diagram is in the localized phase. This is applied in particular to show that, with a very low level of error, the lower bound does not coincide with the critical line. - An analysis of the precise asymptotic behavior of the partition function in the delocalized phase, with particular attention to the effect of rare atypical stretches in the disorder sequence and on whether or not in the delocalized regime the polymer path has a Brownian scaling. - A new proof of the lower bound on the critical line. This proof relies on a characterization of the localized regime which is more appealing for interpreting the numerical data.Comment: accepted for publication on J. Stat. Phy

Are workers rewarded for inconsistent performance?

This paper examines whether workers are rewarded for inconsistent performance by salary premia. Some earlier research suggests that performance inconsistency leads to salary premia, while other research finds premia for consistent performance. Using detailed salary and performance data for top-level footballers in Italy’s Serie A, we find that inconsistency is penalized for some important dimensions of basic performance measures associated with key skills of players, specifically clearances, aerial duels won, and shots on target

Strategic behaviours in a labour market with mobility-restricting contractual provisions: evidence from the National Hockey League

We follow workers' performance along an unbalanced panel dataset over multiple years and study how performance varies at the end of fixed-term contracts, in a labour market where some people face a mobility restricting clause (i.e., a noncompete clause). Focusing on the labour market of the National Hockey League, we analyse players' performance data and contracts with a fixed effect estimator to address empirical limitations in previous studies. We find that, on average, NHL players' performance does not vary. However, our estimations detect substantially heterogeneous behaviours, depending on tenure, perceived expected performance and mobility. Only younger players (i.e., restricted free-agents) with high expected mobility but low expected performance tend to behave strategically and perform better. Differently, older players (i.e., unrestricted free-agents) with high expected mobility tend to underperform, as the option of moving back to European tournaments is more appealing