Non-minimality of corners in subriemannian geometry

We give a short solution to one of the main open problems in subriemannian geometry. Namely, we prove that length minimizers do not have corner-type singularities. With this result we solve Problem II of Agrachev's list, and provide the first general result toward the 30-year-old open problem of regularity of subriemannian geodesics.Comment: 11 pages, final versio

Extremal curves in nilpotent Lie groups

We classify extremal curves in free nilpotent Lie groups. The classification is obtained via an explicit integration of the adjoint equation in Pontryagin Maximum Principle. It turns out that abnormal extremals are precisely the horizontal curves contained in algebraic varieties of a specific type. We also extend the results to the nonfree case.Comment: 30 pages, final versio

DETECTION OF STX2 COLIPHAGES IN STRAIN OF ESCHERICHIA COLI ISOLATED FROM BOVINE FLEECE AND MILK FILTERS

Lambda(4)-phage vectors of gene codifying for synthesis of Shiga-toxins are suspected to be involved in the virulence evolution of Vero-Toxin producing Escherichia coli(VTEC). Herds of domestic or wild ruminants are reservoirs of these bacteria, but excretion with faeces is more frequent in groups of heifers and feeder calves. Studies have shown that slurries produced by infected herds are often positive for VTEC and that Stx2 carrying lambda coliphages can be isolated. These viruses can induce lysogenic cycles only in some strain of Escherichia coli and the Stx gene is then integrated in the bacterial chromosome. When these bacteria also posses other virulence traits, like those responsible for the intimate attachment to the enteric mucosal cells (eae or saa) the recombinant strains might became pathogen for humans. Our research was aimed at detecting the coliphages form ten Stx2 positive strains isolated in our previous studies. We have included strains, possessing or not the 'eae' genes. In addition we have used other isolates originating from slaughterhouses, with the aim of evaluating their susceptibility to the isolated 4-phages. Following induction of a lytic cycle with mitomycin C, the strains were screened by hybridization of plaque blots with Stx2 probes. The purified extracts of eight of the ten strains produced plaque/halos of lysis in cultures of susceptible strains, thus showing these strains were infected by inducible phages, but only one proved to be Stx2 carrier. Attempt to obtain new lysogens using the purified Stx2 phage with other strains 'eae' positive and STx negative isolated from slaughterhouses were unsuccessful. Stx2 lysogens were obtained only using the reference strains DM1187

Studi e ricerche di scienze umane e sociali

[It] Gli studi raccolti in questo volume costituiscono il primo ‘Quaderno’ della nuova Collana di pubblicazioni della Scuola di Scienze Umane e Sociali dell’Ateneo fridericiano, promossa con l’intendimento di facilitare il confronto e il dialogo tra studiosi di varia provenienza, di sollecitare indagini trasversali e interdisciplinari sia su argomenti lontani nel tempo sia su temi di grande attualità che sono parte del nostro vissuto quotidiano. Il volume rappresenta una felice sintesi tra passato e presente, come è prerogativa delle ricerche appartenenti alla cultura umanistica, che ha a oggetto lo studio dell’esperienza umana considerata nella sua globalità. [En] This book belongs to a new Series promoted by the School of Humanities and Social Sciences at Federico II University of Naples, in order to facilitate dialogue among scholars from different disciplines and to encourage interdisciplinary and cross-sectoral approaches on topics, both contemporary and historical. The studies collected in this volume offer a graceful synthesis of past and present, as is typical of the humanities, that study human culture in all its form

Burocrazia e fisco a Napoli tra XV e XVI secolo. La Camera della Sommaria e il Repertorium alphabeticum solutionum fiscalium Regni

Il libro ripercorre i processi di “burocratizzazione” degli uffici finanziari del Regno di Napoli soffermandosi sulla prassi amministrativa della Regia Camera della Sommaria. Esso prende avvio dall’edizione critica del Repertorium Alphabeticum Solutionum Fiscalium Regni Siciliae, un manoscritto cinquecentesco prodotto dalla Sommaria, ricco di informazioni relative all’intera area del Mezzogiorno, divenuto particolarmente prezioso dopo la distruzione della documentazione aragonese dell’Archivio di Stato di Napoli nell’incendio del settembre 1943. La ricerca ha quindi origine dalla lettura “lenta” di un testo, dall’indagine sui suoi caratteri e sulla sua struttura, sulle sue fonti, sul contesto e sulle vicende che condussero alla sua redazione, sulle pratiche di lavoro amministrativo che esso intendeva descrivere e orientare. Il volume ricostruisce poi il lungo processo che portò alla formazione dell’ufficio della Sommaria tra gli ultimi decenni del Duecento e primi del Quattrocento. Ne delinea in seguito le competenze e le modalità di funzionamento in età aragonese, per seguirne infine le vicende fino alla metà del Cinquecento, sulla base di fonti edite e inedite, conservate in diversi archivi e biblioteche, italiane ed europee, senza mai tralasciare il confronto con un’ampia bibliografia internazionale

MECHANICAL MUSCLE PROPERTIES AFTER TWO TYPES OF PLYOMETRIC TRAINING

Strength training effects may be highly specific. This suggestion is not always supported by previous research. Most training studies use strength measures to evaluate the effect of the program. It seems reasonable that a measure of strength does not fully describe the training adaptation. Therefore the design of this experiment is different. All subjects performed a set of 18 maximal contractions (isometric, isokinetic and plyometric) before and after training. Based on this set of measurements a mechanical muscle model was quantified. The coefficients of the model represent muscle properties which underlie force development (force-length, force-velocity relationship and contraction history). By studying the changes of the coefficients an attempt is made to speculate further on the underlying mechanisms which. may be responsible for the strength increase. The proposed study is designed to evaluate the use of a muscle model in investigating training programs. The subjects were divided in 3 groups: one control group (N=10) and two training groups (N=2*10). The training program involved plyometric contractions for the elbowflexors 3 dayslweek for a period of 6 weeks. These plyometric movements consisted of two successive contractions (concentric + kccentric) over an amplitude of 120" at 60"ls. The only difference between both training programs was the fact that sequence of those contractions was reversed namely concentric-eccentric for the CE-group and eccentricconcentric for the EC-group. The three groups (CE, EC. Control) showed no difference in isometric strength pre and post training. For the dynamic strength a significant improvement (P < 0.05) was observed only for both training groups. CE-training resulted in a significant change of the coefficients representing the force-velocity relationship (P < 0.05 for the ecc. part and P < 0.01 for the conc. part). The negative effect of a concentric contraction history was significantly reduced after the EC-training (P < 0.05). It can be concluded that both training groups made similar gains in dynamic force. However, analysis using the model showed that the cause of these force gains was different. For the CE-group the improvement in dynamic force can be attributed to an ameliorated force-velocity relationship whereas for the ECgroup this was due to a reduced influence of the concentric contraction historv. Specific changes in force development after training can be studied using a muscle model. These findings are a useful contribution in determining specific effects of training

Blast waves from violent explosive activity at Yasur Volcano, Vanuatu

Infrasonic and seismic waveforms were collected during violent strombolian activity at Yasur Volcano (Vanuatu). Averaging similar to 3000 seismic events showed stable waveforms, evidencing a low-frequency (0.1-0.3Hz) signal preceding similar to 5-6s the explosion. Infrasonic waveforms were mostly asymmetric with a sharp compressive (5-106Pa) onset, followed by a small long-lasting rarefaction phase. Regardless of the pressure amplitude, the ratio between the positive and negative phases was constant. These waveform characteristics closely resembled blast waves. Infrared imagery showed an apparent cold spherical front similar to 20 m thick, which moved between 342 and 405m/s before the explosive hot gas/fragments cloud. We interpret this cold front as that produced by the vapor condensation induced by the passage of the shock front. We suggest that violent strombolian activity at Yasur was driven by supersonic dynamics with gas expanding at 1.1 Mach number inside the conduit

Pre-treatment high-sensitivity troponin T for the short-term prediction of cardiac outcomes in patients on immune checkpoint inhibitors

Background: Immune checkpoint inhibitors (ICIs) are an emerging option for several advanced metastatic cancers, but may have cardiotoxic effects. The prognostic value of high-sensitivity troponin T (hs-TnT) before treatment start has never been investigated. Materials and methods: Thirty consecutive patients underwent measurement of hs-TnT before starting ICI therapy (pembrolizumab, 23%; nivolumab, 12%; atezolizumab, 6%; durvalumab, 5%). The primary endpoint of cardiovascular death, stroke or transient ischaemic attack, pulmonary embolism and new-onset heart failure, and the secondary endpoint of progression of cardiac involvement according to the CARDIOTOX classification were evaluated after 3&nbsp;months from the first cycle. Results: Patients (median age 68&nbsp;years, 77% men, 13% with coronary artery disease, 90% current or former smokers, 67% overweight or obese and 43% hypertensive) had a median hs-TnT of 12&nbsp;ng/L (interquartile interval 8-23). The primary endpoint occurred only in patients with hs-TnT&nbsp;≥&nbsp;14&nbsp;ng/L at baseline. Therefore, only patients who had hs-TnT&nbsp;≥&nbsp;14&nbsp;ng/L before the first cycle died had a stroke/TIA or new-onset HF. Furthermore, nine out of 13 patients with the secondary endpoint (progression of cardiac disease) had hs-TnT&nbsp;≥&nbsp;14&nbsp;ng/L before the first cycle (P&nbsp;=.012). AUC values were 0.909 for the primary endpoint and 0.757 for the secondary endpoint. The best cut-off was 14&nbsp;ng/L for both the primary (100% sensitivity, 73% specificity) and secondary endpoints (sensitivity 75%, specificity 77%). Conclusions: In patients on ICIs, baseline hs-TnT predicts a composite cardiovascular endpoint and the progression of cardiac involvement at 3&nbsp;months, with 14&nbsp;ng/L as the best cut-off

Remote monitoring of building oscillation modes by means of real-time Mid Infrared Digital Holography

Non-destructive measurements of deformations are a quite common application of holography but due to the intrinsic limits in the interferometric technique, those are generally confined only to small targets and in controlled environment. Here we present an advanced technique, based on Mid Infrared Digital Holography (MIR DH), which works in outdoor conditions and provides remote and real-time information on the oscillation modes of large engineering structures. Thanks to the long wavelength of the laser radiation, large areas of buildings can be simultaneously mapped with sub-micrometric resolution in terms of their amplitude and frequency oscillation modes providing all the modal parameters vital for all the correct prevention strategies when the functionality and the health status of the structures have to be evaluated. The existing experimental techniques used to evaluate the fundamental modes of a structure are based either on seismometric sensors or on Ground-based Synthetic Aperture Radar (GbSAR). Such devices have both serious drawbacks, which prevent their application at a large scale or in the short term. We here demonstrate that the MIR DH based technique can fully overcome these limitations and has the potential to represent a breakthrough advance in the field of dynamic characterization of large structures