Community detection in networks: a heuristic version of Girvan Newman algorithm

I grafi permettono di modellare problemi complessi di diversa natura. Una delle questioni più stimolanti e importanti è il rilevamento delle comunità, cioè l’identificazione di componenti altamente connesse. L’algoritmo di Girvan Newman è in grado di identificare tali componenti con successo, ma non è computazionalmente adatto ad un’analisi di grafi di grandi dimensioni. Pertanto, proponiamo una versione euristica di questo algoritmo, approssimando la misura di betweenness degli archi. Analizziamo le prestazioni della nostra proposta utilizzando reti benchmark.Complex problems in different fields can be modeled by graph data structures. An important and challenging task is the community detection, i.e. the identification of highly connected components. The Girvan Newman algorithm identifies high-quality communities but is not computationally suitable for huge graph analysis. Therefore, we propose a heuristic version of this algorithm, by considering an approximated measure of the edge betweenness. We evaluate the performances of our proposal on benchmark networks

Quality of child healthcare in European countries: common measures across international databases and national agencies

BACKGROUND: The evaluation of child healthcare is not yet widely explored, especially from a cross-country comparison perspective. The routine adoption of measures by national assessment agencies is under-investigated. Though the guiding principles developed at international level call for a child-centric multi-dimensional evaluation of child care, its feasibility is hampered by the availability of robust and harmonized data. METHODS: To explore the data availability, international databases (IDBs) were scrutinized and measures dealing with child health-related issues were collated. In parallel, an ad hoc questionnaire was administrated to 30 Country Agents (CAs) to gather measures routinely adopted at local level. To facilitate the comparison of measures, a three-level conceptual map was developed. RESULTS: The IDBs yielded at 207 measures that pertained mainly to non-health determinants of health, whereas the 352 measures obtained from CAs focused on process and outcome. A set of 33 common measures that related to immunization, morbidity and mortality were identified. CONCLUSIONS: A limited set of measures used both in IDBs and at national level identify common areas of concerns that certainly capture crucial issues with child prevention and health outcomes. However, they are far from satisfying a child-centric multi-dimensional approach to the evaluation of child well-being and well-becoming. There is room for improvement at both international and national levels. IDBs should include and harmonize measures that concern the provision of child-centric services and encompass physical, social and mental development. At the national level, efforts towards the inclusion of measures that concern non-health determinants of health should be pursued

Kinematic and stellar population properties of the counter-rotating components in the S0 galaxy NGC 1366

Context. Many disk galaxies host two extended stellar components that rotate in opposite directions. The analysis of the stellar populations of the counter-rotating components provides constraints on the environmental and internal processes that drive their formation. Aims. The S0 NGC 1366 in the Fornax cluster is known to host a stellar component that is kinematically decoupled from the main body of the galaxy. Here we successfully separated the two counter-rotating stellar components to independently measure the kinematics and properties of their stellar populations. Methods. We performed a spectroscopic decomposition of the spectrum obtained along the galaxy major axis and separated the relative contribution of the two counter-rotating stellar components and of the ionized-gas component. We measured the line-strength indices of the two counter-rotating stellar components and modeled each of them with single stellar population models that account for the \u3b1/Fe overabundance. Results. We found that the counter-rotating stellar component is younger, has nearly the same metallicity, and is less \u3b1/Fe enhanced than the corotating component. Unlike most of the counter-rotating galaxies, the ionized gas detected in NGC 1366 is neither associated with the counter-rotating stellar component nor with the main galaxy body. On the contrary, it has a disordered distribution and a disturbed kinematics with multiple velocity components observed along the minor axis of the galaxy. Conclusions. The different properties of the counter-rotating stellar components and the kinematic peculiarities of the ionized gas suggest that NGC 1366 is at an intermediate stage of the acquisition process, building the counter-rotating components with some gas clouds still falling onto the galaxy. \ua9 ESO 2017

Far-Field Pattern Reconstruction from Near-Field Data Collected via a Nonconventional Plane-Rectangular Scanning: Experimental Testing

This paper deals with the experimental validation of an efficient near-field-far-field (NF-FF) transformation using the planar wide-mesh scanning (PWMS). Such a nonconventional plane-rectangular scanning technique is so named, since the sample grid is characterized by meshes wider and wider when going away from the center, and makes it possible to lower the number of needed measurements, as well as the time required for the data acquisition when dealing with quasi-planar antennas. It relies on the use of the nonredundant sampling representations of electromagnetic fields which employ an oblate ellipsoid or a surface formed by two circular "bowls" with the same aperture diameter but eventually different bending radii to shape a quasi-planar antenna. A two-dimensional optimal sampling interpolation formula allows the reconstruction of the NF data at any point on the measurement plane and, in particular, at those required by the classical NF-FF transformation with the conventional plane-rectangular scanning. The measurements, performed at the planar NF facility of the antenna characterization laboratories of Selex ES, have confirmed the effectiveness of this innovative scanning also from the experimental viewpoint

Singular Spectrum Analysis of Two Photon Interference from Distinct Quantum Emitters

Two-photon interference underlies the functioning of many quantum photonics devices. It also serves as the prominent tool for testing the indistinguishability of distinct photons. However, as their time-spectral profile becomes more involved, extracting relevant parameters, foremost the central frequency difference, may start suffering difficulties. In a parametric approach, these arise from the need for an exhaustive model combined with limited count statistics. Here we discuss a solution to curtail these effects on the evaluation of frequency separation relying on a semiparametric method. The time trace of the quantum interference pattern of two photons from two independent solid-state emitters is preprocessed by means of singular spectral analysis before inspecting its spectral content. This approach allows to single out the relevant oscillations from both the envelope and the noise, without resorting to fitting. This opens the way for robust and efficient on-line monitoring of quantum emitters

A rare diaphragmatic hernia with a delayed presentation of intestinal symptoms following spleno-distal pancreatectomy: a case report

Acquired diaphragmatic hernia, non-related to trauma, is a very rare condition. It can constitute a therapeutic problem and the surgical solution is not always immediately clear. We report the case of a 73-year-old woman with a history of spleno-distal pancreatectomy for a neuroendocrine tumour performed in 2009, who came back to Emergency Room 2 years later, complaining of abdominal pain. Chest radiography and computed tomography were performed; they showed a diaphragmatic hernia with visceral migration into the thorax. The diaphragmatic defect was surgically repaired and the patient had an uneventful post-operative recovery

Synergism between bisphenol a exposure and overweight/obesity in increasing the malignancy risk in a cohort of patients with thyroid nodules

BPA exposure conferred higher risk of thyroid cancer only in case of concomitant overweight/obesity, therefore suggesting a synergistic action between BPA and the excess of adipose tissue in promoting thyroid carcinogenesis

Synthesis and evaluation of wound healing properties of hydro-diab hydrogel loaded with green-synthetized AGNPS: in vitro and in ex vivo studies

In diabetic patients, the presence of neuropathy, peripheral vascular diseases and ischemia, leads to the formation of foot ulcerations with a higher risk of infection because the normal response to bacterial infection is missing. In the aim to control and treat diabetic foot ulcerations (DFUs), wound dressings that are able to absorb exudate, to prevent infections, and to promote wound healing are needed. For this reason, the aim of the present research was to synthetize a biocompatible hydrogel (called HyDrO-DiAb) composed of carboxymethylcellulose loaded with silver nanoparticles (AgNPs) for the treatment of diabetic foot ulcers. In this study, AgNPs were obtained by a green synthesis and, then, were dissolved in a CMC hydrogel that, after a freeze drying process, becomes a flexible and porous structure. The in vitro and in ex vivo wound healing activity of the obtained HyDrO-DiAb hydrogel was evaluatedPeer ReviewedPostprint (published version