Ward identities and Chiral anomaly in the Luttinger liquid

Systems of interacting non relativistic fermions in $d=1$, as well as spin chains or interacting bidimensional Ising models, verify an hidden approximate Gauge invariance which can be used to derive suitable Ward identities. Despite the presence of corrections and anomalies, such Ward identities can be implemented in a Renormalization Group approach and used to exploit nontrivial cancellations which allow to control the flow of the running coupling constants; in particular this is achieved combining Ward identities, Dyson equations and suitable correction identities for the extra terms appearing in the Ward identities, due to the presence of cutoffs breaking the local gauge symmetry. The correlations can be computed and show a Luttinger liquid behavior characterized by non universal critical indices, so that the general Luttinger liquid construction for one dimensional systems is completed without any use of exact solutions. The ultraviolet cutoff can be removed and a Quantum Field Theory corresponding to the Thirring model is also constructed

Low temperature analysis of two dimensional Fermi systems with symmetric Fermi surface

We prove the convergence of the perturbative expansion, based on Renormalization Group, of the two point Schwinger function of a system of weakly interacting fermions in d=2, with symmetric Fermi surface and up to exponentially small temperatures, close to the expected onset of superconductivityComment: 60 pages, 3 figure

Universality of one-dimensional Fermi systems, I. Response functions and critical exponents

The critical behavior of one-dimensional interacting Fermi systems is expected to display universality features, called Luttinger liquid behavior. Critical exponents and certain thermodynamic quantities are expected to be related among each others by model-independent formulas. We establish such relations, the proof of which has represented a challenging mathematical problem, for a general model of spinning fermions on a one dimensional lattice; interactions are short ranged and satisfy a positivity condition which makes the model critical at zero temperature. Proofs are reported in two papers: in the present one, we demonstrate that the zero temperature response functions in the thermodynamic limit are Borel summable and have anomalous power-law decay with multiplicative logarithmic corrections. Critical exponents are expressed in terms of convergent expansions and depend on all the model details. All results are valid for the special case of the Hubbard model.Comment: 56 pages, 2 figures. arXiv admin note: text overlap with arXiv:1106.035

Transabdominal Preperitoneal (TAPP) Inguinal Hernia Repair

The inguinal hernia repair is one of the most frequent surgical procedures: in the world, even year, at least 20.000.000 inguinal hernia repair procedures are performed. Although the laparoscopic approach is widely recognized as a valid treatment for many diseases and some laparoscopic surgical procedures have become gold standard techniques (e. g. cholecystectomy, appendectomy, gastro-esophageal junction surgery), the minimally invasive approach for groin hernia treatment is still very controversial today, but in the last few years, it tends to become the standard practice for 1 day surgery. We present here the technique of laparoscopic Transabdominal Preperitoneal approach (TAPP). The surgical technique is described step-by-step, including surgical details and the new concept of “inverted Y” to achieve the “critical view of safety” for laparoscopic inguinal hernia repair

Abscess and cecum carcinoma in inguinal hernia: case report

Cecal adenocarcinoma within an inguinal hernial sac is an uncommon clinical condition. A primary adenocarcinoma of the cecum in a right sided inguinal hernia is presented and discussed. This case represents one of the unexpected findings in a hernia sac and also very rare septic evolution. This particular condition is a main dignostic and therapeutic challenge

La riparazione dell’ernia ombelicale nella donna in postmenopausa

Gli Autori riportano la loro esperienza sull’impiego della protesi dual-mesh in PTFEe per il trattamento delle ernie ombelicali nelle donne in postmenopausa. La riparazione protesica vs l’intervento classico di Mayo trova giustificazione nella maggior parte dei casi per i deficit biostrutturali delle strutture muscolo-fasciali delle donne in menopausa, deficit legati alla riduzione della funzione ovarica e aggravati da pregresse gravidanze. Una corretta valutazione del trofismo delle strutture della parete addominale e delle dimensioni delle ernie è comunque indispensabile nel porre indicazione alla chirurgia protesica. Nella nostra casistica la morbilità riferita a complicanze precoci è assolutamente trascurabile. A tutt’oggi, sebbene il follow-up sia ancora piuttosto breve, non abbiamo riscontrato casi di recidiva

Pleural mesothelioma risk in the construction industry: a case-control study in Italy, 2000-2018

Objectives Workers in the construction industry have been exposed to asbestos in various occupations. In Italy, a National Mesothelioma Registry has been implemented more than 20 years ago. Using cases selected from this registry and exploiting existing control data sets, we estimated relative risks for pleural mesothelioma (PM) among construction workers. DesignCase-control study. SettingCases from the National Mesothelioma Registry (2000-2018), controls from three previous case-control studies. MethodsWe selected male PM incident cases diagnosed in 2000-2018. Population controls were taken from three studies performed in six Italian regions within two periods (2002-2004 and 2012-2016). Age-adjusted and period-adjusted unconditional logistic regression models were fitted to estimate odds ratios (OR) for occupations in the construction industry. We followed two approaches, one (primary) excluding and the other (secondary) including subjects employed in other non-construction blue collar occupations for >5 years. For both approaches, we performed an overall analysis including all cases and, given the incomplete temporal and geographic overlap of cases and controls, three time or/and space restricted sensitivity analyses. ResultsThe whole data set included 15 592 cases and 2210 controls. With the primary approach (4797 cases and 1085 controls), OR was 3.64 (2181 cases) for subjects ever employed in construction. We found elevated risks for blue-collar occupations (1993 cases, OR 4.52), including bricklayers (988 cases, OR 7.05), general construction workers (320 cases, OR 4.66), plumbers and pipe fitters (305 cases, OR 9.13), painters (104 cases, OR 2.17) and several others. Sensitivity analyses yielded very similar findings. Using the secondary approach, we observed similar patterns, but ORs were remarkably lower. ConclusionsWe found markedly increased PM risks for most occupations in the construction industry. These findings are relevant for compensation of subjects affected with mesothelioma in the construction industry

Inhomogeneous Superconductivity in Condensed Matter and QCD

Inhomogeneous superconductivity arises when the species participating in the pairing phenomenon have different Fermi surfaces with a large enough separation. In these conditions it could be more favorable for each of the pairing fermions to stay close to its Fermi surface and, differently from the usual BCS state, for the Cooper pair to have a non zero total momentum. For this reason in this state the gap varies in space, the ground state is inhomogeneous and a crystalline structure might be formed. This situation was considered for the first time by Fulde, Ferrell, Larkin and Ovchinnikov, and the corresponding state is called LOFF. The spontaneous breaking of the space symmetries in the vacuum state is a characteristic feature of this phase and is associated to the presence of long wave-length excitations of zero mass. The situation described here is of interest both in solid state and in elementary particle physics, in particular in Quantum Chromo-Dynamics at high density and small temperature. In this review we present the theoretical approach to the LOFF state and its phenomenological applications using the language of the effective field theories.Comment: RevTex, 83 pages, 26 figures. Submitted to Review of Modern Physic

Il trattamento del carcinoma del retto basso nel paziente anziano fragile. Contributo casistico

Il carcinoma del retto è di frequente riscontro nella popolazione anziana, nell’ambito della quale morbilità e mortalità correlate alla terapia chirurgica sono spesso aggravate da patologie concomitanti. Tuttavia, previo un accurato studio preoperatorio e la rigida selezione dei pazienti in categorie di rischio, è possibile l’attuazione di procedure chirurgiche sicure ed efficaci. Nel nostro studio abbiamo incluso 149 pazienti affetti da carcinoma del retto distale, suddivisi tra soggetti con più di 75 anni e con meno di 75 anni. Gli interventi eseguiti sono stati: resezione curativa in 94 casi, interventi palliativi in 19, escissione locale in 31; anche tra i pazienti di età superiore a 75 anni abbiamo ottenuto buoni risultati per quanto riguarda le complicanze e la mortalità postoperatorie. Possiamo dunque concludere che le procedure chirurgiche da noi eseguite garantiscono, anche in pazienti anziani selezionati, buoni risultati in termini di controllo sia del rischio perioperatorio sia della malattia neoplastic

L’uso del drenaggio nel trattamento “per primam” delle cisti pilonidali recidive

Il trattamento delle fistole sacrococcigee recidive è tuttora contro - verso, in quanto tutte le metodiche più comunemente attuate deter - minano disagi non indifferenti per i pazienti (metodi “aperti”) o sono gravate da un’alta incidenza di ulteriori recidive. Sulla base di tale constatazione, gli Autori hanno proceduto ad una revisione della loro casistica comprendente 27 pazienti con fisto - le recidive, selezionati con precisi criteri e trattati con escissione “en bloc” di tutto il tessuto patologico e successiva chiusura “per primam” della ferita, previa apposizione di un drenaggio aspirativo sucessiva - mente rimosso in seconda o terza giornata. L’uso routinario del drenaggio, la copertura antibiotica sino alla sesta-settima giornata dopo l’intervento e l'accurata disinfezione della ferita e della cute circostante, condotta giornalmente sino alla rimozione dei punti, ci hanno permesso di registrare incoraggianti risultat