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In this paper, a multi-cylinder, internal combustion engine model is presented. The paper is focused on a new modular, physically based and lumped parameter (zero dimensional) approach, leading to a complete and coherent model structure. The model is conceived to be used with general purpose simulation software, as MATLAB/Simulink. The mean value outputs of the model (pressure, temperature, mass flow, torque) are compared with experimental data, collected by a Fiat 1.8 liter engine, in order to perform a standard identification and validation procedure.

Stimulation of J774 macrophages with lipopolysaccharide (LPS) leads to the release of large amounts of prostaglandins (PGs) generated by the inducible isoform of cyclooxygenase (COX-2). Nitric oxide (NO), a pleiotropic free radical, has been demonstrated to modulate the release of a broad range of inflammatory mediators, amongst these PGs. In the present study we investigated the molecular mechanism by which NO affects cyclooxygenase pathway. Incubation of J774 cells with LPS caused an increase of prostaglandin E2 production and COX-2 protein expression which was prevented in a concentration-dependent fashion by pre-incubating cells with sodium nitroprusside (SNP) and S-nitroso-glutathione (GSNO), two NO-generating agents. Electrophoretic mobility shift assay indicated that both NO-generating agents blocked LPS-induced activation of nuclear factor-kappaB (NF-kappaB) by increasing IkappaB-alpha protein expression and blocking nuclear translocation of NF-kappaB subunits p50 and p65. SNP and GSNO also inhibited nuclear factor-interleukin-6 (NF-IL6) activation. These results show for the first time that SNP and GSNO down-regulate LPS-induced COX-2 expression by inhibiting NF-kappaB and NF-IL6 activation and suggest a negative feed-back mechanism that may be important for limiting excessive or prolonged PGs production in pathological events.

Disease of the iliac fossa can often be accompanied by non-specific symptoms and some of these are exclusively caused by the compression of bulky masses of other neighboring structures. In young women a differential diagnosis is a non trivial task as several possible causes have to be taken into account. Thus, intraligamentary tumors, which are extremely rare finding, are frequently confused with uterus, ovary or intestinal tumors. Even if myomas are the most benign tumors of the female genital tract, broad ligament leiomyomas are an unusual finding in women of reproductive age. These tumors are often asymptomatic until they reach a volume likely to cause symptoms related to the mass pressure. An accurate patient's anamnesis and examination serve as a guide to further examinations. Ultrasound is the first line imaging as it can show ovarian or other pelvic mass and doesn't involve exposure to radiations in young patients, who can be pregnant. We describe the clinical presentation and imaging features of a broad ligament leiomyoma, which presented as an inguinal mass in a patient with a right iliac fossa pain. We also report our diagnostic process performing the differential diagnosis with other potential pathologies of RIF. In these cases, a preoperative disease classification discriminating the benign or malignant tumor nature is closely linked to the proper patient management.Le patologie occupanti le aree addominali inferiori sono frequentemente accompagnate da una sintomatologia aspecifica causata, il più delle volte, da compresione «ab estrinseco» a carico degli organi contigui. Nelle donne in età fertile la diagnosi differenziale gioca un ruolo di primo piano per una corretta gestione del paziente. Avviene così che alcune tipologie di tumori rari, come quelli intralegamentari, vengano confusi con tumori di altra proveninenza (utero, annessi o intestino). Alcuni tra questi, come il leiomioma del legamento largo, inusuali nelle donne giovani, insorgano e persistano senza alcuna manifestazione clinica sino al momento in cui il volume di massa non porti a compressioni nei confronti di strutture contigue. In questi casi una accurata anamnesi è fondamentale e deve essere sempre accompagnata da una indagine ecografica che accerti in maniera mininvasiva i l’origine ed i rapporti delle masse sospette. Vengono di seguito descritti: il percorso diagnostico e gestionale in un raro caso di leiomioma del legamento largo in una paziente con sintomatologia dolorosa in fossa iliaca destra. Nel nostro caso la diagnosi differenziale preoperatoria ha consentito un corretto approccio chirurgico discriminando sulla la natura benigna della lesione individuata.

Il contributo costituisce la seconda edizione, totalmente riveduta ed aggiornata, della trattazione dell'intera disciplina legale in materia di simulazione del contratto e degli atti unilaterali, unitamente ad una compiuta analisi delle ipotesi applicative esaminate alla luce della giurisprudenza più recente della Corte di Cassazione.

Il saggio prende in considerazione le letture di Elsa Morante in ambito antropologico e etnografico, sulla base dei libri da lei posseduti e conservati nel Fondo Morante della Biblioteca Nazionale Centrale di Roma. L'attenzione riservata a Ernesto De Martino appare complessivamente modesta; assai più vivo è l'interesse che la scrittrice dimostra verso l'opera di Mircea Eliade, più consono alle sue inclinazioni e alla sua sensibilità. Fra i punti di contatto spiccano l'idea di storia e la fascinazione per la sapienza orientale.

The essay deals with Italian parliamentary novel and also with its links with European culture.

Presentazione di Primo Levi narratore, focalizzata sulle opere di maggiore organicità e respiro: le due narrazioni testimoniali Se questo è un uomo e La tregua, il romanzo storico Se non ora, quando? e il lungo saggio sul fenomeno del Lager I sommersi e i salvati, cui va aggiunta l’autobiografia (rispetto ai canoni del genere, intenzionalmente frammentaria e reticente) Il sistema periodico. A differenza di quanto accade nelle narrazioni brevi, incentrate spesso (come ha scritto Federico Pianzola) sui temi della genesi e della metamorfosi, in queste opere Levi mostra di prediligere la forma della storia di salvazione, dove però l’esito appare sempre provvisorio, e insidiato da nuove minacce.

The essay analyses Dickens' Bleak House

In order to lower the Nitrogen Oxides (NOx) concentration in internal combustion engine emissions and to improve performance, Exhaust Gas Recirculation (EGR) and Scavenging mechanism are introduced. EGR recirculates a fraction of the exhaust gas back into the cylinders, thus diluting the intake air. This lowers the maximum combustion temperature and, since the formation of NOx is heavily dependent on temperature, it results in a reduction of NOx concentration. Similarly, the Scavenging phenomenon is the air mass flowing from intake manifold directly to exhaust manifold, due to an overlap of intake and exhaust valves, without participating at the combustion. In this paper, the authors present a mean value engine model, aimed at the challenging purpose of the analysis of EGR and Scavenging. The model is based on an innovative approach for engine dynamics conceived mainly on the analogy with electric systems.

Automotive companies commonly adopt hardware-in-the-loop simulators to develop new control strategies in order to reduce the effort and the cost of the testing phase. This work aims at presenting a simple intake manifold air dynamics model, suited for HIL simulations, taking into account the nonlinear effects caused by VVA system during all its operating modes, i.e. full lift, early closure, late opening and multi lift. The performances of the proposed model are finally presented through comparisons with experimental data collected by a 1.4 liter Fiat SI engine, showing good reliability and excellent robustness.

We investigated the role of constitutive transcription factor nuclear factor kappaB (NF-kappaB) in nitric oxide (NO)-mediated apoptosis in J774 macrophages. Our results show that NF-kappaB is present in untreated J774 cells in a form constitutively active. Incubation of cells with sodium nitroprusside (SNP) and S-nitroso-glutathione (GSNO), two NO-generating compounds, caused: (a) inhibition of constitutive NF-kappaB/DNA binding activity; (b) decrease of cell viability; (c) DNA fragmentation; (d) ApopTag positivity. Pyrrolidine dithiocarbamate (PDTC) and N-alpha-para-tosyl-L-lysine chloromethyl ketone (TLCK), two inhibitors of NF-kappaB activation, showed the same effects of both NO-generating compounds. Furthermore, SNP and GSNO as well as PDTC and TLCK significantly increased the cytoplasmic level of IkappaBalpha. All together these results demonstrate that constitutive NF-kappaB protects J774 macrophages from NO-induced apoptosis. Moreover, these findings show, for the first time, that NO-generating compounds may induce apoptosis in J774 macrophages by down-regulating constitutive NF-kappaB/DNA binding activity and suggest a novel mechanism by which NO induces apoptosis.