Period two implies chaos for a class of ODEs: a dynamical system approach

The aim of this note is to set in the field of dynamical systems a recent theorem by Obersnel and Omari about the presence of periodic solutions of all periods for a class of scalar time-periodic first order differential equations without uniqueness, provided a subharmonic solution (and thus, for instance, a solution of period two) does exist. Indeed, making use of the Bebutov flow, we try to clarify in what sense the term "chaos" has to be understood and which dynamical features can be inferred for the system under analysis.Comment: 10 page

Chaotic dynamics in the Volterra predator-prey model via linked twist maps

We prove the existence of infinitely many periodic solutions and complicated dynamics, due to the presence of a topological horseshoe, for the classical Volterra predator--prey model with a periodic harvesting. The proof relies on some recent results about chaotic planar maps combined with the study of geometric features which are typical of linked twist maps.Comment: 24 pages, 4 figure

Some Remarks on Fixed Points for Maps which are Expansive along one Direction

We present some fixed point theorems for planar maps which satisfy a property of path–expansion along a certain direction. We also show some links between these fixed point theorems and other recent results about covering relations and topological horseshoes

Caloric vestibular stimulation reduces pain and somatoparaphrenia in a severe chronic central post-stroke pain patient: a case study

Central post-stroke pain is a neuropathic syndrome characterized by intolerable contralesional pain and, in rare cases, somatic delusions. To date, there is limited evidence for the effective treatments of this disease. Here we used caloric vestibular stimulation to reduce pain and somatoparaphrenia in a 57-year-old woman suffering from central post-stroke pain. Resting-state functional magnetic resonance imaging was used to assess the neurological effects of this treatment. Following vestibular stimulation we observed impressive improvements in motor skills, pain, and somatic delusions. In the functional connectivity study before the vestibular stimulation, we observed differences in the patient's left thalamus functional connectivity, with respect to the thalamus connectivity of a control group (N = 20), in the bilateral cingulate cortex and left insula. After the caloric stimulation, the left thalamus functional connectivity with these regions, which are known to be involved in the cortical response to pain, disappeared as in the control group. The beneficial use of vestibular stimulation in the reduction of pain and somatic delusion in a CPSP patient is now documented by behavioral and imaging data. This evidence can be applied to theoretical models of pain and body delusions

MMsPred: a bioactivity and toxicology predictive system

In the last decade, the development and use of new methods in combinatorial chemistry and high-throughput screening has dramatically increased the number of known biologically active compounds. Paradoxically, the number of drugs reaching the market has not followed the same trend, often because many of the candidate drugs present poor qualities in absorption, distribution, metabolism, excretion, and toxicological properties (ADME-Tox). The ability to recognize and discard bad candidates early in the drug discovery steps would save lost investments in time and money. Machine learning techniques could provide solutions to this problem.
The goal of my research is to develop classifiers that accurately discriminate between active and inactive molecules for a specific target. To this end, I am comparing the effectiveness of the application of different machine learning techniques to this problem.	As a source of data we have selected a set of PubChem's public BioAssays1. In addition, with the objective of realizing a real-time query service with our predictors, we aim to keep the features describing the chemical compounds relatively simple.
At the end of this process, we should better understand how to build statistical models that are able to recognize molecules active in a specific bioassay, including how to select the most appropriate classification technique, and how to describe compounds in such a way that is not excessively resource-consuming to generate, yet contains sufficient information for the classification. We see immediate applications of such technology to recognize compounds with high-risk of toxicity, and also to suggest likely metabolic pathways that would process it

The Seal suite of distributed software for high-throughput sequencing

23-23Pubblicat

Il supporto dei sistemi informativi territoriali nella modellazione dei sistemi di trasporto regionali:la collaborazione tra CRiMM e CRS4 (settembre - dicembre 1998)

In questo rapporto si d a una sintesi delle attività svolte presso il CRS4 nell'ambito della collaborazione con il Centro di Ricerca Modelli Mobilità (CRiMM) dell'Università di Cagliari per lo studio propedeutico al Piano Pluriennale di Protezione Civile Regionale

Automated and traceable processing for large-scale high-throughput sequencing facilities

Scaling up production in medium and large high-throughput sequencing facilities presents a number of challenges. As the rate of samples to process increases, manually performing and tracking the center’s operations becomes increasingly difficult, costly and error prone, while processing the massive amounts of data poses significant computational challenges. We present our ongoing work to automate and track all data-related procedures at the CRS4 Sequencing and Genotyping Platform, while integrating state-of-the-art processing technologies such as Hadoop, OMERO, iRODS, and Galaxy into our automated workflows. Currently, the core system is in its testing phase and it is on schedule to be in production use at CRS4 by May 2013. The results thus far obtained are encouraging and the authors are confident that the CRS4 Platform will increase its efficiency and capacity thanks to this system. In the near future, the integration components will be released as as open source software.23-24Pubblicat