U_A(1) symmetry breaking, scalar mesons and the nucleon spin problem in an effective chiral field theory

We establish a relationship between the scalar meson spectrum and the $U_A (1)$ symmetry-breaking 't Hooft interaction on one hand and the constituent quark's flavor-singlet axial coupling constant $g_{A, Q}^{(0)}$ on the other, using an effective chiral quark field theory. This analysis leads to the new sum rule $g_{A, Q}^{(0)}[m_{\eta '}^{2} + m_{\eta}^{2} - 2 m_{K}^{2} ]\simeq - m_{f_{0}^{'}}^{2} - m_{f_{0}}^{2} + 2 m_{K_{0}^{*}}^{2}$, where $\eta^{'}, \eta, K$ are the observed pseudoscalar mesons, $K_{0}^{*}$ is the strange scalar meson at 1430 MeV and $f_{0}, f_{0}^{'}$ are "the eighth and the ninth" scalar mesons. We discuss the relationship between the constituent quark flavor-singlet axial coupling constant $g_{A, Q}^{(0)}$ and the nucleon one $g_{A, N}^{(0)}$ (``nucleon's spin content'') in this effective field theory. We also relate $g_{A, Q}^{(0)}$, as well as the flavour-octet constituent quark axial coupling constant $g_{A, Q}^{(1)}$ to vector and axial-vector meson masses in general as well as in the tight-binding limit.Comment: 16 pages, 3 figures, RevTex, to appear in Nucl.Phys.

Effective Hadron Dynamics: From Meson Masses to the Proton Spin Puzzle

We construct a three flavor chiral Lagrangian of pseudoscalars and vectors with special emphasis on the symmetry breaking terms. Comparing tree level two and three point functions with experiment allows us to first, fix the parameters of the model (including the light quark mass ratios) and second, to predict $m(K^{*+})-m(K^{*\circ}),\, \Gamma(K^*\rightarrow K\pi)$ and $\Gamma(\phi\rightarrow K {\overline K})$. The last mentioned quantities come out reasonably well, in contrast to an ``ordinary" $SU(3)$ treatment. For this purpose we need ``second order" symmetry breakers involving the vector fields analogous to those needed for the chiral perturbation theory program with only pseudoscalars. An improved description of the $\eta-\eta^\prime$ system is also given. We then use the soliton sector of this improved chiral Lagrangian to investigate some aspects of baryon physics which are especially sensitive to symmetry breaking. For this purpose a fairly elaborate ``cranking" techinque is employed in connection with the collective Hamiltonian. In addition to the ``strong" baryon mass spectrum a careful investigation is made of the non-electromagnetic part of the neutron-proton mass difference. This work is needed to improve our previous estimates concerning the two component approach to the ``proton spin" puzzle. We find that both the ``matter" and ``glue" contributions are small but they do tend to cancel each other.Comment: 33 pages, LaTe

Putative Light Scalar Nonet

We investigate the "family" relationship of a possible scalar nonet composed of the a_0(980), the f_0(980) and the \sigma and \kappa type states found in recent treatments of \pi\pi and \pi K scattering. We work in the effective Lagrangian framework, starting from terms which yield "ideal mixing" according to Okubo's original formulation. It is noted that there is another solution corresponding to dual ideal mixing which agrees with Jaffe's picture of scalars as qq\bar q \bar q states rather than as q\bar q states. At the Lagrangian level there is no difference in the formulation of the two cases (other than the numerical values of the coefficients). In order to agree with experiment, additional mass and coupling terms which break ideal mixing are included. The resulting model turns out to be closer to dual ideal mixing than to conventional ideal mixing; the scalar mixing angle is roughly -17 degrees in a convention where dual ideal mixing is 0 degrees.Comment: 24 pages, 3 figure

Rapporto Energia 2012 - Dati sull\u2019energia in Sicilia

Con il Rapporto Energia 2012, elaborato a cura del Dipartimento dell\u2019Energia - Osservatorio regionale e Ufficio statistico per l\u2019energia, si intende monitorare il settore dell\u2019energia in Sicilia. L\u2019analisi dei dati relativi al sistema energetico siciliano rappresenta un valido punto di partenza per guidare gli interventi verso il raggiungimento degli obiettivi che la Regione si \ue8 posta ed ha concordato a livello nazionale ed europeo. Gli impegni a livello europeo, rappresentati sinteticamente dal modello \u201c 20-20-20\u201d, hanno attribuito all\u2019Italia l\u2019obiettivo del 17% di copertura dei propri consumi energetici da fonti rinnovabili. Per il conseguimento degli obblighi internazionali assunti, il Governo Italiano ha legiferato in materia, emanando recentemente un apposito decreto ministeriale, c.d. \u201cBurden Sharing\u201d, che ripartisce tra le singole regioni gli obiettivi di produzione di energia da fonte rinnovabile. Nel presente documento viene illustrato un modello energetico regionale per la determinazione dei consumi, che pu\uf2 rappresentare un valido ausilio anche per la ripartizione dell\u2019obiettivo di Burden Sharing agli enti locali. Il Rapporto, attraverso la ricerca e l\u2019elaborazione dei dati forniti svolge, pertanto, il compito di rappresentare la realt\ue0 energetica regionale e di fornire un utile supporto alla conoscenza del sistema energetico in Sicilia. Dai dati elaborati si evince il notevole risultato raggiunto per gli impianti fotovoltaici in Sicilia, il cui trend relativo alla potenza installata continua ad essere in forte ascesa, mentre il settore eolico non registra variazioni di rilievo rispetto all\u2019anno precedente. Il rapporto 2012 contiene anche le informazioni relative ai comuni siciliani che hanno aderito all\u2019iniziativa della Commissione Europea (Covenant of Mayors), meglio conosciuta col nome Patto dei Sindaci, nata per coinvolgere attivamente e su base volontaria le citt\ue0 europee nel percorso verso la sostenibilit\ue0 energetica ed ambientale. L\u2019analisi dei dati contenuti nel report permette agli enti locali di orientare gli interventi di pianificazione energetica volti al risparmio energetico, all\u2019aumento dell\u2019energia da fonte rinnovabile e alla diminuzione delle emissioni di CO2 in atmosfera, elementi base dei Piani d\u2019Azione per l\u2019Energia Sostenibile (PAES) di cui al Patto dei Sindaci. Dall\u2019analisi dei prezzi di alcuni prodotti petroliferi , si osserva che l\u2019Italia risulta al secondo posto a livello europeo per fiscalit\ue0 e prezzo della benzina, mentre il prezzo del gas in Sicilia \ue8 superiore a quello degli altri ambiti nazionali. La produzione di greggio siciliano rappresenta il 12% del totale nazionale, mentre le lavorazioni di greggio e semilavorati rappresentano circa il 38% del totale nazionale, con una forte movimentazione in uscita dai porti della Sicilia di prodotti raffinati ed allo stesso tempo un forte ingresso di greggio dai porti in prossimit\ue0 delle raffinerie. La produzione di gas naturale dai giacimenti siciliani costituisce il 4% del totale nazionale, mentre le importazioni attraverso i punti d\u2019ingresso presenti in Sicilia, nel 2011 sono state il 33,6%, in diminuzione rispetto al 2010, a causa degli eventi bellici libici. Dal raffronto della rete elettrica in diverse regioni italiane, in particolare analizzando la rete ad altissima tensione (380 kV), si osserva che in Sicilia la densit\ue0 di rete risulta pari a 9,84 m/kmq, notevolmente inferiore alla densit\ue0 presente in Lombardia, che \ue8 di 58,54 m/kmq. Tale gap determina le note limitazioni allo sfruttamento dell\u2019energia elettrica prodotta da impianti a fonte rinnovabile non compatibile con il trend fortemente crescente del fotovoltaico in Sicilia e con la rilevante quantit\ue0 di energia elettrica prodotta da fonte eolica. In materia di certificazione energetica degli edifici in Sicilia si registra una maggiore sensibilit\ue0 dei cittadini, con un forte aumento degli attestati di certificazione energetica pervenuti al Dipartimento dell\u2019energia. Infine, il rapporto contiene alcune informazioni relative al catasto regionale degli impianti termici finalizzato all\u2019attivit\ue0 di controllo, manutenzione ed ispezione degli impianti stessi

Cystic Adventitial Disease of the Popliteal Artery: Radical Surgical Treatment After Several Failed Approaches. A Case Report and Review of the Literature

Adventitial cystic disease is a rare nonatheromatous cause of popliteal artery disease. We report the case of a 49-year-old male patient who presented with left calf claudication caused by adventitial cystic disease. Popliteal artery resection followed by autologous vein graft interposition and Percutaneous Transluminal Angioplasty (PTA) stenting led to recurrence. The patient was finally successfully treated by bypass with autologous vein. No postoperative complications occurred, and patency was preserved at 33-month follow-up. Several different treatment options are possible; however, a primary radical surgical treatment with extra-anatomical medial bypass with autologous vein seems preferable

Time to onset of bisphosphonate-related osteonecrosis of the jaws: a multicentre retrospective cohort study

Objectives: Osteonecrosis of the jaw (ONJ) is a potentially severe adverse effect of bisphosphonates (BP). Although the risk of ONJ increases with increasing duration of BP treatment, there are currently no reliable estimates of the ONJ time to onset (TTO). The objective of this study was to estimate the TTO and associated risk factors in BP-treated patients. Subjects and Methods: Retrospective analysis of data from 22 secondary care centres in seven countries relevant to 349 patients who developed BP-related ONJ between 2004 and 2012. Results: The median (95%CI) TTO was 6.0 years in patients treated with alendronate (n = 88) and 2.2 years in those treated with zoledronate (n = 218). Multivariable Cox regression showed that dentoalveolar surgery was inversely associated, and the use of antiangiogenics directly associated, with the TTO in patients with cancer treated with zoledronate. Conclusions: The incidence of ONJ increases with the duration of BP therapy, with notable differences observed with respect to BP type and potency, route of administration and underlying disease. When data are stratified by BP type, a time of 6.0 and 2.2 years of oral alendronate and intravenous zoledronate therapy, respectively, is required for 50% of patients to develop ONJ. After stratification by disease, a time of 5.3 and 2.2 years of BP therapy is required for 50% of patients with osteoporosis and cancer, respectively, to develop ONJ. These findings have significant implications for the design of future clinical studies and the development of risk-reduction strategies aimed at either assessing or modulating the risk of ONJ associated with BP.Objectives: Osteonecrosis of the jaw (ONJ) is a potentially severe adverse effect of bisphosphonates (BP). Although the risk of ONJ increases with increasing duration of BP treatment, there are currently no reliable estimates of the ONJ time to onset (TTO). The objective of this study was to estimate the TTO and associated risk factors in BP-treated patients. Subjects and Methods: Retrospective analysis of data from 22 secondary care centres in seven countries relevant to 349 patients who developed BP-related ONJ between 2004 and 2012. Results: The median (95%CI) TTO was 6.0 years in patients treated with alendronate (n = 88) and 2.2 years in those treated with zoledronate (n = 218). Multivariable Cox regression showed that dentoalveolar surgery was inversely associated, and the use of antiangiogenics directly associated, with the TTO in patients with cancer treated with zoledronate. Conclusions: The incidence of ONJ increases with the duration of BP therapy, with notable differences observed with respect to BP type and potency, route of administration and underlying disease. When data are stratified by BP type, a time of 6.0 and 2.2 years of oral alendronate and intravenous zoledronate therapy, respectively, is required for 50% of patients to develop ONJ. After stratification by disease, a time of 5.3 and 2.2 years of BP therapy is required for 50% of patients with osteoporosis and cancer, respectively, to develop ONJ. These findings have significant implications for the design of future clinical studies and the development of risk-reduction strategies aimed at either assessing or modulating the risk of ONJ associated with BP