Boundary Spatiotemporal Correlations in a Self-Organized Critical Model of Punctuated Equilibrium

In a semi-infinite geometry, a 1D, M-component model of biological evolution realizes microscopically an inhomogeneous branching process for $M \to \infty$. This implies in particular a size distribution exponent $\tau'=7/4$ for avalanches starting at a free end of the evolutionary chain. A bulk--like behavior with $\tau'=3/2$ is restored if `conservative' boundary conditions strictly fix to its critical, bulk value the average number of species directly involved in an evolutionary avalanche by the mutating species located at the chain end. A two-site correlation function exponent ${\tau_R}'=4$ is also calculated exactly in the `dissipative' case, when one of the points is at the border. These results, together with accurate numerical determinations of the time recurrence exponent $\tau_{first}'$, show also that, no matter whether dissipation is present or not, boundary avalanches have the same space and time fractal dimensions as in the bulk, and their distribution exponents obey the basic scaling laws holding there.Comment: 5 pages, 3 eps figure

Empedocle e Freud: riflessioni su logica e linguaggio

The present piece, first presented on 19 November 2016 at the Centre Léon Robin (CNRS-Univ. Paris-Sorbonne-ENS Ulm) as part of the“Présocratiques” Seminar, is an investigation of the relationship between Empedocles and Freud. The analysis is divided into three parts: the first section examines the nature of Freud’s engagement with Empedocles; next, consideration is given to the similarities between their doctrines, based on the extant fragments of the Empedoclean corpus; finally, I offer a series of observations about Empedocles’ poetic style, which shares strong affinities with the spoken word in a manner typical of the oral tradition and is freighted with corporeal and emotional significance. It is here that we see the emergence of one of the key concepts of psychoanalysis: the relationship between logos and alogon, between that which can be rationally analysed and that which can be intuited but which eludes the domain of logos

Diets of shags Phalacrocorax aristotelis and cormorants P. carbo in Norway and possible implications for gadoid stock recruitment

The diets of shags and cormorants were studied in Norway through analyses of regurgitated pellets. Although this method has many limitations, indications were that both species rely heavily on small gadoids (Gadidae) and sand eels (Ammodytidae) for food throughout their range, but also eat other fish species when available. There was considerable dietary overlap between species, despite a tendency for cormorants to eat larger fish and more benthic items than shags. Predation by shags and cormorants could be a factor limiting the recruitment of cod and saithe into what are now severely reduced, but commercially important stocks in the Norwegian and Barents Seas

Science, Utilization, Conservation and Co-Management of the George River Caribou Herd

Four objectives of the George River Caribou Workshop were identified: (1) to consider present and past assessments of caribou numbers and population trends in the GRC (2) to explore the role of environmental factors such as climate and habitat change on population dynamics (3) to consider actual and potential human activities on the population and distribution of the caribou (4) to discuss caribou management strategies and the co-management concept. The workshop was organized around four half-day sessions focused on each of these objectives and each session featured three or four keynote speakers

Nasal pathologies in patients with obstructive sleep apnoea

Nasal obstruction is a frequent condition in patients with obstructive sleep apnoea (OSA). Nasal obstruction leads to mouth breathing, which is thought to destabilise the upper airway to aggravate the condition. Three conditions could be considered as the cause of the nasal breathing obstruction: anatomical conditions of the nose (septum deviation, hypertrophy of the inferior turbinates), chronic rhinosinusitis (CRS) and chronic nasal inflammation caused by allergic rhinitis or non-allergic cellular rhinitis. In this prospective study, we present an evaluation of all these possible rhino-sinusal aspects in OSA patients to correlate different nasal pathologies with nasal obstruction. Fifty patients with a diagnosis of OSA were enrolled in the study. In 70% of OSA patients, nasal obstruction was confirmed by clinical evaluation and rhinomanometry testing. Normal rhino-sinus aspects were present in only 20% of OSAS patients, whereas one or more pathological rhino-sinus conditions were present in the remaining 80%. The percentage of OSA patients with a diagnosis of allergic rhinitis and non-allergic rhinitis was 18% and 26% respectively. Non-allergic rhinitis with neutrophils (NARNE) was the most frequent type of cellular rhinitis diagnosed in OSA patients (20% of cases). The results of the present study support and extend the observation that rhinitis is present in OSA patients. Mucosal inflammation caused by these conditions could be the cause of upper airway patency impairment inducing nasal mucosa swellin

Variation of Efficacy of Filtering Face Pieces Respirators over Time in a Dental Setting: A Pilot Study

Since aerosol continuously persists in dental settings, where different procedures and patients come in succession, the use of oronasal masks is highly recommended. Among them, respirators known as Filtering Face Pieces (FFP) show a protective superiority compared to surgical masks. Even concerning respirators classified as non-reusable, it is not known how many hours of use are necessary to compromise their filtering capacity. The aim of this study is to investigate the variations of filtering capacity of an FFP2 respirator over time, in order to safely optimize the timing of its use. Five respirators were worn by the same operator during clinical activity for different usage times (8, 16, 24, 32, 40 h), and one respirator was kept unused. All respirators underwent a bacterial filtration efficacy (BFE) test. T-test for paired data with Bootstrap technique and Wilcoxon test for paired data compared BFE values of the five tested FFP2s respectively at each time, and the areas with the corresponding values of the control respirator (FFp2-F). A generalized linear mixed effect model (GLM) was applied considering type of respirator and time as fixed effects and intercept as random effect. No significant statistical differences were present in the BFE of each time. Data obtained by the present study highlight the important ability of FFP2s to maintain their BFE over time, suggesting a long lasting protective function