The Stefan-Boltzmann law in a small box and the pressure deficit in hot SU(N) lattice gauge theory

The blackbody radiation in a box L^3 with periodic boundary conditions in thermal equilibrium at a temperature T is affected by finite-size effects. These bring about modifications of the thermodynamic functions which can be expressed in a closed form in terms of the dimensionless parameter LT. For instance, when LT~4 - corresponding to the value where the most reliable SU(N) gauge lattice simulations have been performed above the deconfining temperature T_c - the deviation of the free energy density from its thermodynamic limit is about 5%. This may account for almost half of the pressure deficit observed in lattice simulations at T~ 4 T_c.Comment: 9 pages, 2 figures v2:a side remark on the final result and references adde

Prevalence and correlates for self-reported sleep problems among nursing students

Introdution. University students report significantly worse sleep quality than the general population. Sleep problems are related to increased health concerns, irritability, depression, fatigue, attention and concentration difficulties, along with poor academic performance. The aim of this paper is to conduct a survey based on a questionnaire that would characterize night time and daytime habits in nursing students to estimate the prevalence of chronic insomnia, sleep disturbance and their correlates. Methods. We conducted a cross-sectional survey among 364 nursing students of the University of L?Aquila, in Italy. Self-reported sleep data were derived from Sleep and Daytime Habits Questionnaire (SDHQ) that covered sleep and daytime habits and academic progress. Anxiety and depression symptoms were assessed by the Mental Health Invenctory-5 (MHI-5) questionnaire. A supplement includes information about lifestyle, health status and physical activity. Results. The overall prevalence of insomnia was 26,7%. It increased significantly from 10,3% for students aged inf. 20 years to 45,5% for those aged over 40 years. The prevalence of sleep problems were 9,4% for disorders of initiating sleep, 8,3% for disrupted sleep, 7,7% for early morning awakening and subjectively poor quality of sleep 22,3%. Multiple logistic regression analysis showed that greater age was significantly associated with an increased risk of insomnia. Other risk predictors of insomnia were headache, severe depression and self perception of poor quality of life. Daytime sleepiness and morning tiredness were significantly associated with current smoking habit and painful physical condition. The risk of unsatisfactory academic progress increased significantly in students reported poor sleep quality. Discussion. Our study demonstrates that sleep problems are very common among students, and supports the need to assess sleep prob-lems and identify students at risk regarding school achievement

Considerations about the experience in experimental microsurgery in Catania University

In the 1980s and 1990s Microsurgery has had a great diffusion in Italy. Our group, who worked in University of Catania, Sicily, got in touch with Sun Lee, the father of Experimental Microsurgery, and applied actively the microsurgical techniques both in the experimental and clinical field.Several Courses have been organized in Catania to involve young doctors who have been charmed by this new surgical branch.It is our opinion that in the present time Microsurgery could play an important role in the training of the general surgery residents. An experimental microsurgical training, together with simulators, could guarantee a more complete training of the residents, helping them to be familiar with surgical instruments and suture materials, improving their skill in performing microvascular anastomoses (carotid and femoral arteries) and more complex surgical operations (portocaval shunt) and leading them to a valid research activity

Citron kinase controls abscission through RhoA and Anillin.

The small GTPase RhoA plays a crucial role in the different stages of cytokinesis, including contractile ring formation, cleavage furrow ingression, and midbody abscission. Citron kinase (CIT-K), a protein required for cytokinesis and conserved from insects to mammals, is currently considered a cytokinesis-specific effector of active RhoA. In agreement with previous observations, we show here that, as in Drosophila cells, CIT-K is specifically required for abscission in mammalian cells. However, in contrast with the current view, we provide evidence that CIT-K is an upstream regulator rather than a downstream effector of RhoA during late cytokinesis. In addition, we show that CIT-K is capable of physically and functionally interacting with the actin-binding protein anillin. Active RhoA and anillin are displaced from the midbody in CIT-K-depleted cells, while only anillin, but not CIT-K, is affected if RhoA is inactivated in late cytokinesis. The overexpression of CIT-K and of anillin leads to abscission delay. However, the delay produced by CIT-K overexpression can be reversed by RhoA inactivation, while the delay produced by anillin overexpression is RhoA-independent. Altogether, these results indicate that CIT-K is a crucial abscission regulator that may promote midbody stability through active RhoA and anillin