Color flux tubes in SU(3)SU(3) Yang-Mills theory: an investigation with the connected correlator

In this work we perform an investigation of the flux tube between two static color sources in four dimensional $SU(3)$ Yang-Mills theory, using the so called connected correlator. Contrary to most previous studies we do not use any smoothing algorithm to facilitate the evaluation of the correlator, that is performed using only stochastically exact techniques. We first examine the renormalization properties of the connected operator, then we present our numerical data for the longitudinal chromoelectric component of the flux tube, that are used to extract the dual superconductivity parameters.Comment: 8 pages, 6 eps figure

Dell’Università: tra storia, percorsi, problemi. Note a margine di un convegno

Ripensando al valore simbolico oltre che eminentemente culturale del convegno del 12 ottobre 2012 dedicato a Claudio Desinan dai suoi “discepoli”, viene naturale affermare che la storia della Facoltà di Magistero/Scienze della Formazione dell’Università degli studi di Trieste è stato luogo particolarmente attento ai princìpi qui sommariamente evocati. Non sono mancati, come ovunque d’altronde, anni di minor tensione ideale, ma credo di poter dire che sul lungo periodo essi hanno rappresentato fasi di passaggio, non momenti caratterizzanti l’insieme della vita e del lavoro di questa comunità

Melnikov theory for weakly coupled nonlinear RLC circuits

We apply dynamical system methods and Melnikov theory to study small amplitude perturbation of coupled nonlinear RLC systems. In particular we show persistence of such orbits connecting singularities in finite time provided a Melnikov like condition holds

Colonization by benthic algae on submarine in the southeastern area of the Gulf of Trieste

Scopo dello studio è stato quello di analizzare i processi di colonizzazione macroalgale su differenti tipi di substrati artificiali, in due aree del Golfo di Trieste (area nord-occidentale, area sud-orientale). Le due aree sono ecologicamente differenti, in termini di idrodinamismo, batimetria, esposizione a moto ondoso, sedimentazione, torpidità e struttura geologica del fondale. Tali fattori influenzano in maniera differente il processo di colonizzazione algale. Le fasi delle colonizzazioni macroalgali sono state seguite mediante immersioni subacquee dopo 2,6,12 e 24 mesi e i campioni sono stati prelevati tramite grattaggi del substrato. Per l’analisi dei campionamenti è stata utilizzata una scala arbitraria, già utilizzata in precedenti studi (Munda, 1978, 1979, 1991a, 2005). Dall’analisi dei campioni sono state osservate variazioni nel popolamento di alcune specie appartenenti ai gruppi Cystoseira e Sargassum come anche nelle associazioni di Fucales, quasi scomparse dal Golfo. In altri casi invece variazioni spazio-temporali (stagionalità) nella colonizzazione, sono state relazionate con la profondità del fondale, la tipologia dei substrati utilizzati e le diverse strategie di colonizzazione in particolare per quanto riguarda diatomee e macroalghe

Steady-state visual evoked potentials and phase synchronization in migraine

We investigate phase synchronization in EEG recordings from migraine patients. We use the analytic signal technique, based on the Hilbert transform, and find that migraine brains are characterized by enhanced alpha band phase synchronization in presence of visual stimuli. Our findings show that migraine patients have an overactive regulatory mechanism that renders them more sensitive to external stimuli.Comment: 4 page

The compensatory dynamic of inter-hemispheric interactions in visuospatial attention revealed using rTMS and fMRI

A balance of mutual tonic inhibition between bi-hemispheric posterior parietal cortices is believed to play an important role in bilateral visual attention. However, experimental support for this notion has been mainly drawn from clinical models of unilateral damage. We have previously shown that low-frequency repetitive TMS (rTMS) over the intraparietal sulcus (IPS) generates a contralateral attentional deficit in bilateral visual tracking. Here, we used functional magnetic resonance imaging (fMRI) to study whether rTMS temporarily disrupts the inter-hemispheric balance between bilateral IPS in visual attention. Following application of 1 Hz rTMS over the left IPS, subjects performed a bilateral visual tracking task while their brain activity was recorded using fMRI. Behaviorally, tracking accuracy was reduced immediately following rTMS. Areas ventro-lateral to left IPS, including inferior parietal lobule (IPL), lateral IPS (LIPS), and middle occipital gyrus (MoG), showed decreased activity following rTMS, while dorsomedial areas, such as Superior Parietal Lobule (SPL), Superior occipital gyrus (SoG), and lingual gyrus, as well as middle temporal areas (MT+), showed higher activity. The brain activity of the homologues of these regions in the un-stimulated, right hemisphere was reversed. Interestingly, the evolution of network-wide activation related to attentional behavior following rTMS showed that activation of most occipital synergists adaptively compensated for contralateral and ipsilateral decrement after rTMS, while activation of parietal synergists, and SoG remained competing. This pattern of ipsilateral and contralateral activations empirically supports the hypothesized loss of inter-hemispheric balance that underlies clinical manifestation of visual attentional extinction

Aggiornamenti epidemiologici sull’echinococcosi animale in Italia

Cystic Echinococcosis (CE) is one of the most widespread parasitoses in the Mediterranean Region (MR). This is due to various factors, the most important being the close association between man, sheep and dogs in areas where open farming is practised. Although this disease has been known for several years and many studies have been carried out, nowadays in Italy there are no complete epidemiological data on its diffusion and distribution. The available data show that CE is mainly diffused in those districts where the sheep-dog cycle can be perpetuated, such as central and southern Italy, and the islands. Furthermore, no data are available on biomolecular characterisation of the strains of Echinococcus granulosus in Italy, apart form those in Sardinia, where the G1 (sheep-dog) and G7 (pig-dog) strains were recently isolated. One of the reasons why CE is a problem with no easy solution is undoubtedly the difficulty of making a certain diagnosis in the dog, the principal definitive host of E. granulosus

Sublethal concentrations of 17-AAG suppress homologous recombination DNA repair and enhance sensitivity to carboplatin and olaparib in HR proficient ovarian cancer cells

The promise of PARP-inhibitors(PARPis) in the management of epithelial ovarian cancer(EOC) is tempered by the fact that approximately 50% of patients with homologous recombination (HR)-proficient tumors do not respond well to these agents. Combination of PARPis with agents that inhibit HR may represent an effective strategy to enhance their activity in HR-proficient tumors. Using a bioinformatics approach, we identified that heat shock protein 90 inhibitors(HSP90i) may suppress HR and thus revert HR-proficient to HR-deficient tumors. Analysis of publicly available gene expression data showed that exposure of HR-proficient breast cancer cell lines to HSP90i 17-AAG(17-allylamino-17-demethoxygeldanamycin) downregulated HR, ATM and Fanconi Anemia pathways. In HR-proficient EOC cells, 17-AAG suppressed HR as assessed using the RAD51 foci formation assay and this was further confirmed using the Direct Repeat-GFP reporter assay. Furthermore, 17-AAG downregulated BRCA1 and/or RAD51 protein levels, and induced significantly more γH2AX activation in combination with olaparib compared to olaparib alone. Finally, sublethal concentrations of 17-AAG sensitized HR-proficient EOC lines to olaparib and carboplatin but did not affect sensitivity of the HR-deficient OVCAR8 line arguing that the 17-AAG mediated sensitization is dependent on suppression of HR. These results provide a preclinical rationale for using a combination of olaparib/17-AAG in HR-proficient EOC

On a diffusion model with absorption and production

We discuss the structure of radial solutions of some superlinear elliptic equations which model diffusion phenomena when both absorption and production are present. We focus our attention on solutions defined in R (regular) or in R \ {0} (singular) which are infinitesimal at infinity, discussing also their asymptotic behavior. The phenomena we find are present only if absorption and production coexist, i.e., if the reaction term changes sign. Our results are then generalized to include the case where Hardy potentials are considered