81 research outputs found
Reperti lapidei di et\ue0 romana rinvenuti a Fornovo Taro: provenienza e circolazione
Nelle collezioni del Museo Archeologico Nazionale di Parma tra i reperti litici di et\ue0 romana figurano anche tre oggetti recuperati a Fornovo Taro o nelle sue adiacenze diversi per contesto di ritrovamento e destinazione d\u2019uso, di cui si \ue8 analizzata la pietra ai fini di determinarne la provenienza e le possibili rotte commerciali. In particolare sono stati presi in esame:- una epigrafe frammentaria (n.inv. L 49), databile al II secolo d.C., gi\ue0 murata in uno dei pilastri della Pieve ed entrata a far parte delle collezioni museali nel 18671;
- una piccola scultura raffigurante Afrodite accovacciata secondo il modello dello scultore ellenistico Doidalsas (n.inv. MANPr 31963), recuperata negli anni Ottanta del secolo scorso al margine occidentale di Piazza IV Novembre, databile ai primi decenni sempre del II secolo d.C.2;
- una base di colonna (mancante di n.inv. e abbreviata con la sigla BCG), recuperata nel 1980 a Roncolungo di Sivizzano tra i materiali accatastati ai margini della strada statale dal proprietario del terreno in attesa di disfarsene
The U-PHOS experience within the ESA student REXUS/BEXUS programme: a real space hands-on opportunity
Large Diameter Pulsating Heat Pipe for Future Experiments on the International Space Station:Ground and Microgravity Thermal Response
Cyclosporine in patients with steroid-resistant nephrotic syndrome: an open-label, nonrandomized, retrospective study
Arachidonic acid-evoked Ca^{2+} signals promote nitric oxide release and proliferation in human endothelial colony forming cells
Arachidonic acid (AA) stimulates endothelial cell (EC) proliferation through an increase in intracellular Ca^{2+} concentration ([Ca^{2+}]_{i}), that, in turn, promotes nitric oxide (NO) release. AA-evoked Ca^{2+} signals are mainly mediated by Transient Receptor Potential Vanilloid 4 (TRPV4) channels. Circulating endothelial colony forming cells (ECFCs) represent the only established precursors of ECs. In the present study, we, therefore, sought to elucidate whether AA promotes human ECFC (hECFC) proliferation through an increase in [Ca^{2+}]_{i} and the following activation of the endothelial NO synthase (eNOS). AA induced a dose-dependent [Ca^{2+}]_{i} raise that was mimicked by its non-metabolizable analogue eicosatetraynoic acid. AA-evoked Ca^{2+} signals required both intracellular Ca^{2+} release and external Ca^{2+} inflow. AA-induced Ca^{2+} release was mediated by inositol-1,4,5-trisphosphate receptors from the endoplasmic reticulum and by two pore channel 1 from the acidic stores of the endolysosomal system. AA-evoked Ca^{2+} entry was, in turn, mediated by TRPV4, while it did not involve store-operated Ca^{2+} entry. Moreover, AA caused an increase in NO levels which was blocked by preventing the concomitant increase in [Ca^{2+}]_{i} and by inhibiting eNOS activity with NG-nitro-l-arginine methyl ester (l-NAME). Finally, AA per se did not stimulate hECFC growth, but potentiated growth factors-induced hECFC proliferation in a Ca^{2+} - and NO-dependent manner. Therefore, AA-evoked Ca^{2+} signals emerge as an additional target to prevent cancer vascularisation, which may be sustained by ECFC recruitment
U-PHOS Project: Development of a Large Diameter Pulsating Heat Pipe Experiment on board REXUS 22
Upgraded Pulsating Heat Pipe Only For Space (U-PHOS): results of the 22nd Rexus Sounding Rocket Campaign
Upgraded Pulsating Heat Pipe Only For Space (U-Phos): Results of the 22nd Rexus Sounding Rocket Campaign
A large tube may still behave, to a certain extent, as a capillary in a micro-gravity environment. This very basic concept is here applied to a two-phase passive heat transfer devices in order to obtain a new family of hybrid wickless heat pipes. Indeed, a Loop Thermosyphon, which usually consists of a large tube, closed end to end in a loop, evacuated and partially filled with a working fluid and intrinsically gravity assisted, may become a capillary tube in space condition and turn its thermo-fluidic behavior into a so called Pulsating Heat Pipe (PHP), or better, a Space Pulsating Heat Pipe (SPHP). Since the objective of the present work is to experimentally demonstrate the feasibility of such a hybrid device, a SPHP has been designed, built, instrumented and tested both on ground and microgravity conditions on the 22nd ESA REXUS Sounding Rocket Campaign. Ground tests demonstrate that the device effectively work as a gravity assisted loop thermosyphon, whether the sounding rocket data clearly reveal a change in the thermal hydraulic behavior very similar to the PHP. Since a microgravity period of approximately 120s is not sufficient to reach a pseudo steady state regime, further investigation on a longer term weightless condition is mandatory
U-PHOS Project: Development of a Large Diameter Pulsating Heat Pipe Experiment on board REXUS 22
U-PHOS Project aims to analyse and characterise the behaviour of a large diameter Pulsating Heat Pipe (PHP) on board REXUS 22 sounding rocket. A PHP is a passive thermal control device consisting of a serpentine capillary tube, evacuated, partially filled with a working fluid and finally sealed. In this configuration, the liquid and vapour phases are randomly distributed in the form of liquid slugs and vapour plugs. The heat is efficiently transported by means of the self-sustained oscillatory fluid motion driven by the phase change phenomena. On ground conditions, a small diameter is required in order to obtain a confined slug flow regime. In milli-gravity conditions, buoyancy forces become less intense and the PHP diameter may be increased still maintaining the slug/plug flow configuration typical of the PHP operation. Consequently, the PHP heat power capability may be increased too. U-PHOS aims at proving that a Large Diameter PHP effectively works in milli-g conditions by characterizing its thermal response during a sounding rocket flight. The actual PHP tube is made of aluminum (3 mm inner diameter, filled with FC-72), heated at the evaporator by a compact electrical resistance, cooled at the condenser by a Phase Change Material (PCM) embedded in a metallic foam. The tube wall temperatures are recorded by means of Fibre Bragg Grating (FBG) sensors; the local fluid pressure is acquired by means of a pressure transducer. The present work intends to report the actual status of the project, focusing in particular on the experiment improvements with respect to the previous campaign
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