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We revisit the two dimensional non-Abelian Thirring model in order to investigate its fixed point structure and the corresponding renormalization group (RG) flow. For this purpose we discuss the bosonization of the model, and we present different, but of course equivalent, bosonic versions of the theory. The bosonic theories are illuminating in that they exhibit the fixed points in a manifest way, and also possess a remarkable strong/weak duality that sheds light on the fixed point structure of the theory. We study the RG flow through the computation of the Zamolodchikov $C$-function and of the $\beta$-function in the large-level limit. Within this framework, we discuss how close to the infrared fixed point the RG flow can reach, since this point is strictly unachievable due to an emergent gauge invariance., Comment: 33 pages, 2 figures, comments are welcome!

OBJECTIVE: To identify the determinants of mobility among people aged 50+ from Finland, Spain and Poland. STUDY DESIGN: Observational cross-sectional population study. MAIN OUTCOME MEASURES: A mobility score was based on responses to items referring to body movements, walking, moving around and using transportation. Determinants of mobility were entered in hierarchical regression models in the following order: sociodemographic characteristics, health habits, chronic conditions, description of general state of health, vision and hearing, social networks, built environment. RESULTS: Complete data were available for 3902 participants (mean age 65.1, SD 9.8). The final model explained 64.7% of the variation in mobility. The most relevant predictors were: pain, age and living in Finland, presence of arthritis, stroke and diabetes, high-risk waist circumference, physical inactivity, and perceiving the neighborhood environment as more exploitable. CONCLUSIONS: Our results provide public health indications that could support concrete actions to address the modifiable determinants of mobility. These include the identification and treatment of pain-related problems, increasing the level of physical activity and the improvement of neighborhood features in terms of presence of general utility places or means of transportation. These factors can be modified with short- to medium-term interventions and such a change could improve the mobility of ageing population, with evident benefits for health.

In this work we analyze the low energy nonrelativistic limit of Dirac theory in the framework of effective field theory. By integrating out the high energy modes of Dirac field, given in terms of a combination of the two-components Weyl spinors, we obtain a low energy effective action for the remaining components, whose equation of motion can then be compared to the Pauli-Schr\"odinger equation after demanding normalization of the wave function. We then discuss the relevance of the terms in the effective action in the context of an anisotropic dimensional analysis which is suitable for nonrelativistic theories., Comment: 20 pages, typos corrected, minor improvements, references added

To help policy makers determine the need for current regulations (which require cooking of swill prior to feeding to swine), an assessment of the likelihood of exposing domestic swine in the continental United States of America (USA) to selected foreign animal disease agents by feeding uncooked swill was carried out. The hazard was assumed to originate from contraband food items entering the USA and subsequently being discarded in household waste. Such food waste may be collected by licensed waste feeders and fed to swine. This study showed that, of the four diseases studied, the probability of exposure was highest for the classical swine fever (hog cholera) virus. The median annual likelihood of one or more contaminated loads of swill being fed to swine in the continental USA was estimated as follows: classical swine fever virus: 0.063, foot and mouth disease virus: 0.043, swine vesicular disease virus: 0.005, African swine fever virus: 0.005.

Cardiopulmonary bypass (CPB) has a risk of cerebral injury, with an important role of gaseous micro-emboli (GME) coming from the CPB circuit. Pulsatile perfusion is supposed to perform specific conditions for supplementary GME activity. We aimed to determine whether pulsatile CPB augments production and delivery of GME and evaluate the role of different events in GME activity during either type of perfusion. Twenty-four patients who underwent on-pump coronary artery bypass grafting surgery at the University of Verona were divided equally into two groups-pulsatile perfusion (PP) group and nonpulsatile perfusion (NP) group. The circuit included a JostraHL-20 roller pump set in pulsatile or nonpulsatile mode, an open Sorin Synthesis membrane oxygenator with integrated screen-type arterial filter, and phosphorylcholine-coated tubes. Hemodynamic flow evaluation was performed in terms of energy equivalent pressure and surplus hemodynamic energy (SHE). GME were counted by means of a GAMPT BCC200 bubble counter (GAMPT, Zappendorf, Germany) with two probes placed at postpump and postarterial filter positions. Results were evaluated in terms of GME number, GME volume, number of over-ranged GME from both probes, and series of filtering indexes. In PP mode, the pump produced and delivered along the circuit significantly higher amounts of SHE than in NP mode. At the venous postpump site, GME number was significantly higher during PP but no difference was found in terms of GME volume or number of over-ranged bubbles. No significant difference in GME number, GME volume, or number of over-ranges was found at the postarterial filter site. Filtering indexes were similar between the two groups. Neither type of perfusion was shown to contribute to excessive GME production during the most important perfusionist manipulation. Pulsatility leads to GME increment by splitting and size diminishing of the existing bubbles but not by additional gas production. PP augmented GME number at the venous postpump site, while mean volume remained comparable with NP. Sorin Synthesis oxygenator showed high efficacy in GME removal during either type of perfusion. Supplementary GME production and delivery during typical perfusionist manipulations did not depend on perfusion type.

Parental socioeconomic position (SEP) is a known determinant of a child’s health. We aimed to investigate whether a low parental education, as proxy of SEP, has a direct effect on physician-diagnosed asthma, current asthma and current allergic rhinitis in children, or whether associations are mediated by exposure to other personal or environmental risk factors. This study was a secondary data analysis of two cross-sectional studies conducted in Italy in 2006. Data from 2687 adolescents (10–14 years) were analyzed by a path analysis model using generalized structural equation modelling. Significant direct effects were found between parental education and family characteristics (number of children (coefficient = 0.6229, p < 0.001) and crowding index (1.1263, p < 0.001)) as well as with exposure to passive smoke: during pregnancy (maternal: 0.4697, p < 0.001; paternal: 0.4854, p < 0.001), during the first two years of children’s life (0.5897, p < 0.001) and currently (0.6998, p < 0.001). An indirect effect of parental education was found on physician-diagnosed asthma in children mediated by maternal smoking during pregnancy (0.2350, p < 0.05) and on current allergic rhinitis mediated by early environmental tobacco smoke (0.2002; p < 0.05). These results suggest the importance of promotion of ad-hoc health policies for promoting smoking cessation, especially during pregnancy.