Molluscs associated with a Sardinian deep water population of Corallium rubrum (Linnι, 1758)

Molluscan species living in association with Corallium rubrumcolonies are poorly known. Specimensfound on the branches of red coral colonies located off Capo Caccia (Alghero – SS, West Sardinia,Mediterranean Sea) were studied by analyzing red coral branches collected at a depth of between 100 and120 m; their assemblage was made up of 44 species, all belonging to the classes Gastropoda and Bivalvia.Some data on the geographical distribution, ecology, taxonomy and dominance of these species, bothalive and dead, are given and the most interesting are commented on. Among the recorded species Triviamultilirata, Simnia purpurea, Coralliophila brevis, Ocinebrina paddeui, Pleurotomella demosia, Palliolumstriatum and Pseudamussium sulcatum deserve attention. Moreover, the second finding of livingspecimens of Asperarca secreta, described only on loose valves, is reported, and finally the prey-predatorrelationships among several gastropods and Cnidarians are confirmed

Lattice effects on the spin dynamics in antiferromagnetic molecular rings

We investigate spin dynamics in antiferromagnetic (AF) molecular rings at finite temperature in the presence of spin-phonon (s-p) interaction. We derive a general expression for the spin susceptibility in the weak s-p coupling limit and then we focus on the low-frequency behavior, in order to discuss a possible microscopic mechanism for nuclear relaxation in this class of magnetic materials. To lowest order in a perturbative expansion, we find that the susceptibility takes a Lorentzian profile and all spin operators ($S^x$, $S^y, S^z$) contribute to spin dynamics at wave vectors $q\ne 0$. Spin anisotropies and local s-p coupling play a key role in the proposed mechanism. Our results prove that small changes in the spatial symmetry of the ring induce qualitative changes in the spin dynamics at the nuclear frequency, providing a novel mechanism for nuclear relaxation. Possible experiments are proposed.Comment: 4 pages, 2 figures. to appear in PR

Dynamic spin Jahn-Teller effect in small magnetic clusters

We study the effect of spin-phonon coupling in small magnetic clusters, concentrating on a S=1/2 ring of 4 spins coupled antiferromagnetically. If the phonons are treated as classical variables, there is a critical value of the spin-phonon coupling above which a static distortion occurs. This is a good approximation if the zero point energy is small compared to the energy gain due to the distortion, which is true for large exchange interactions compared to the phonons energy ($J\gg\hbar\omega$). In the opposite limit, one can integrate out the phonon degrees of freedom and get an effective spin hamiltonian. Using exact diagonalizations to include the quantum nature of both spins and phonons, we obtain the spectrum in the whole range of parameters and explicit the crossover between the classical and quantum regimes. We then establish quantitatively the limits of validity of two widely used approaches (one in the quantum and one in the classical limits) and show that they are quite poor for small magnetic clusters. We also show that upon reducing $\hbar\omega/J$ the first excitation of a 4-site cluster becomes a singlet, a result that could be relevant for Cu$_2$Te$_2$O$_5$Br$_2$

Type 2 diabetes mellitus, physical activity, exercise self-efficacy, and body satisfaction. An application of the transtheoretical model in older adults

Physical activity (PA) is a relevant component of the treatment of Type 2 diabetes mellitus (T2DM). However, to prevent its related morbidities, PA requires an immediate and lasting change of lifestyle. Exercise self-efficacy and body satisfaction were used in a sample of older adults with T2DM, classified in different stages of change, to predict levels of PA. Results show that exercise self-efficacy increases linearly from precontemplation to maintenance stage, while body satisfaction shows an inverted U shape. However, only stages of change, other than exercise self-efficacy, add a significant and noticeable contribution to prediction of levels of PA. This evidence claims a tailored approach to PA in older adults with T2DM and advises behavioural health interventions based on exercise self- efficacy

Inter-individual variability in psychological outcomes of supervised exercise in adults with Type 2 Diabetes

Exercise is a key component in the management of Type 2 Diabetes Mellitus (T2DM), however despite the strong evidence of its protective effects, a majority of the population with this diagnosis remains inactive and those who start an exercise program are not willing to train themselves over the long-term. Self-ef cacy and perceived stress are related to barriers to exercise in T2DM, therefore the aim of this longitudinal study is to investigate variations across time and individual differences in both variables as effects of a supervised exercise training (6 months) in a small sample of persons diagnosed with T2DM. Results show a general decline in the mean values of self-ef cacy and perceived stress at 6 months and a high individual variability in both variables. These results support the need to develop customized pro- grams of exercise in T2DM that take into account different phases of the exercise process and individual variability.El ejercicio es un componente clave en la prevención y el tratamiento de Diabetes Mellitus Tipo 2 (DMT2); sin embargo, a pesar de la fuerte evidencia de sus efectos protectores, la mayoría de las personas con este diagnóstico permanece inactiva y aquellos que comienzan un programa de ejercicio no están dispuestos a entrenar a largo plazo. La autoefcacia y la percepción de estrés se relacionan con las barreras para realizar ejercicio en pacientes T2DM; por lo tanto, el objetivo de este estudio longitudinal consiste en investigar las variaciones a través del tiempo y las diferencias individuales en ambas variables, como efectos de un entrenamiento de ejercicio supervisado (6 meses), en una muestra pequeña de pacientes diagnosticados con TD2M. Los resultados muestran una disminución general de los valores promedio de la autoefcacia y del estrés percibido a los 6 meses y una alta variabilidad individual en ambas variables. Estos resultados apoyan la necesidad de desarrollar programas personalizados de ejercicio en pacientes T2DM con el objetivo de considerar las diferentes fases del proceso de ejercicio y de la variabilidad individual

Spectroscopic and in silico studies on the interaction of substituted pyrazolo[1,2-a]benzo[1,2,3,4]tetrazine-3-one derivatives with c-myc g4-dna

Herein we describe a combined experimental and in silico study of the interaction of a series of pyrazolo[1,2-a]benzo[1,2,3,4]tetrazin-3-one derivatives (PBTs) with parallel G-quadruplex (GQ) DNA aimed at correlating their previously reported anticancer activities and the stabilizing effects observed by us on c-myc oncogene promoter GQ structure. Circular dichroism (CD) melting experiments were performed to characterize the effect of the studied PBTs on the GQ thermal stability. CD measurements indicate that two out of the eight compounds under investigation induced a slight stabilizing effect (2–4 °C) on GQ depending on the nature and position of the substituents. Molecular docking results allowed us to verify the modes of interaction of the ligands with the GQ and estimate the binding affinities. The highest binding affinity was observed for ligands with the experimental melting temperatures (Tms). However, both stabilizing and destabilizing ligands showed similar scores, whilst Molecular Dynamics (MD) simulations, performed across a wide range of temperatures on the GQ in water solution, either unliganded or complexed with two model PBT ligands with the opposite effect on the Tms, consistently confirmed their stabilizing or destabilizing ability ascertained by CD. Clues about a relation between the reported anticancer activity of some PBTs and their ability to stabilize the GQ structure of c-myc emerged from our study. Furthermore, Molecular Dynamics simulations at high temperatures are herein proposed for the first time as a means to verify the stabilizing or destabilizing effect of ligands on the GQ, also disclosing predictive potential in GQ-targeting drug discovery

Impact of lesion delineation and intensity quantisation on the stability of texture features from lung nodules on ct: A reproducible study

Computer-assisted analysis of three-dimensional imaging data (radiomics) has received a lot of research attention as a possible means to improve the management of patients with lung cancer. Building robust predictive models for clinical decision making requires the imaging features to be stable enough to changes in the acquisition and extraction settings. Experimenting on 517 lung lesions from a cohort of 207 patients, we assessed the stability of 88 texture features from the following classes: first-order (13 features), Grey-level Co-Occurrence Matrix (24), Grey-level Difference Matrix (14), Grey-level Run-length Matrix (16), Grey-level Size Zone Matrix (16) and Neighbouring Grey-tone Difference Matrix (five). The analysis was based on a public dataset of lung nodules and open-access routines for feature extraction, which makes the study fully reproducible. Our results identified 30 features that had good or excellent stability relative to lesion delineation, 28 to intensity quantisation and 18 to both. We conclude that selecting the right set of imaging features is critical for building clinical predictive models, particularly when changes in lesion delineation and/or intensity quantisation are involved

Parylene C-based, breathable tattoo electrode for high-quality biopotential measurements

A breathable tattoo electrode for bio-potential recording based on a Parylene C nanofilm is presented in this study. The proposed approach allows for the fabrication of micro-perforated epidermal submicrometer-thick electrodes that conjugate the unobtrusiveness of Parylene C nanofilms and the very important feature of breathability. The electrodes were fully validated for electrocardiography (ECG) measurements showing performance comparable to that of conventional disposable gelled Ag/AgCl electrodes, with no visible negative effect on the skin even many hours after their application. This result introduces interesting perspectives in the field of epidermal electronics, particularly in applications where critical on-body measurements are involved