117 research outputs found
Esperienze di gestione, monitoraggio e razionalizzazione di consumi di energia elettrica nell'Ateneo Genovese
No full textHPLC determination of benzydamine and metabolite N-oxide in plasma following oral administration or topical application in man, using fluorimetric detection
No full textNon invasive techniques for identification and characterization of polymers in contemporary artworks.
No full textContemporary art collections include a huge variety of polymeric materials - briefly identified as “plastics” - that react differently to the same environmental conditions and can undergo dramatically diverse degradation processes. Hence, a fundamental starting point in any plan of preservation of plastics artworks is the identification of types of polymers constituting the objects and, when possible, the assessment of the degradation stage for each polymer identified. At present, tests available for plastics identification are borrowed from industrial field: in most cases they require sampling and are destructive or, at least, micro-destructive. This fact limits their applicability in the museums context, where the integrity of the artwork is a fundamental value to be taken into account. Nowadays, methodologies based on evaluation of visual appearance and odors remain the most practiced alternative for a simple, non destructive classification of materials in plastic artworks. Thus, non invasive methods for rapid identification of materials and diagnosis of degradation are highly required for preservation of contemporary art collections. The aim of this work is to study applicability and potentialities of two non-invasive spectroscopic techniques, namely FORS (Fiber Optic Reflectance Spectroscopy) and Dielectric Spectroscopy, as measurement principles of portable systems for the quick identification of plastics and characterization of most frequent degradation phenomena. FORS is an optical technique based on acquisition of the reflectance spectrum in the UV-Vis-NIR spectral region (300-2100nm). By means of a portable spectrophotometer equipped with optical fibers probe-head, the spectrum is recorded in-situ in a totally non-invasive way, and, thanks to the versatility of optical fiber accessories, any point of the object can be measured without constraints due to size or shape of the object. The spectral data on the extended UV-Vis-NIR are exploitable for different purposes: the NIR spectrum can provide indications about the occurrence of chemical species characteristics of a given polymeric class. Instead, the spectral reflectance in the visible region is used for colorimetric analysis and is a powerful tool for monitoring changes in appearance that are symptoms of several degradation phenomena. Dielectric Spectroscopy consists in the measurement of the dielectric permittivity of materials using sensors operating in a very broad frequency region of the electromagnetic spectrum (from a few Hz up to tens of GHz). Dielectric permittivity is a physical parameter that can be related to the capability of polarization of the material in presence of an applied electrical field, and hence its measurement provides information about the tendency of molecular dipoles to follow the orientation of the applied field. This is in turn related to chemical and physical properties of materials. In this context dielectric spectroscopy can be useful for distinguishing between given classes of polymers (e.g. nitrate and acetate of cellulose), as well as for assessing structural molecular alterations (chain length changes) and monitoring ageing phenomena. Both these techniques are already used in conservation field for non-invasive diagnostic on artworks. Nevertheless, so far they have been employed and optimized for characterization of antique artifacts and ‘traditional’ artistic materials: the idea is now to apply these approaches to contemporary artworks, and in particular to polymeric materials. To this purpose, the first unavoidable step is to build specific spectral references databases of polymers of interests in the museum context. Therefore, a set of certified standards (Resinkit®) of the most common polymers has been characterized using both FORS and dielectric spectroscopy, and preliminary results are discussed here. This work is carried out in the framework of the on-going EC Research Project “Popart” (Preservation Of Plastic ARTefacts in museum collections). The research leading to these results has received funding from the European Community’s Seventh Framework Programme FP7/2007-2013 under grant agreement n° 212218
Penetration of prulifloxacin into gynaecological tissues after single and repeated oral administrations
No full textThis study aimed to evaluate the penetration into gynaecological tissues of ulifloxacin, the active metabolite of prulifloxacin, a once-daily fluoroquinolone administered once or in repeated doses
Piccolo - Its Historical Development, Construction, and Use in Solo, Chamber and Orchestral Music
No full textThe bachelor's thesis "Picollo. Its Historical Development, Construction and Use in Solo, Chamber and Orchestral Music." is concerned with a picollo, an instrument related to the flute. The first chapter introduces the history of both the flute and the picollo to the reader. It also includes the description of constructional changes of the instruments and their functions from the beginnings until the present day.
In the second chapter, the author focused only on the picollo, its construction and the materials it may be made of (metal, wood). The author also mentioned the significant international producers of picollos and attention was also paid to the maintenance of the instrument. The last chapter examines the possibilities of picollo's use as a solo instrument or as a member of a chamber, symphonic or operatic orchestra
Non-invasive techniques applied to the alchemical codex of the State Archive of Florence
No full textThis paper focuses on the application of non-invasive techniques to study a peculiar object, an alchemical codex completely made of lead stored at the State Archive of Florence.1 The sheets of the codex appeared entirely covered by thick and heterogeneous corrosion patinas for which a restoration was planned for their removal. This activity was supported by analytical investigations to characterise the materials that made up the patinas using non-invasive techniques. The codex pages were initially documented with imaging techniques. Subsequently, spectroscopic data were acquired on each sheet using spot analytical techniques: Total Reflectance Fourier Transform Infrared Spectroscopy (TR FT-IR), Fibre Optics Reflectance Spectroscopy (FORS), X-Ray Fluorescence (XRF), Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD). The identification of deterioration compounds has been extremely useful for the conservator to deal with the removal of dangerous and disfiguring patinas
Piccolo - Its Historical Development, Construction, and Use in Solo, Chamber and Orchestral Music
No full textBakalářská práce "Pikola - historický vývoj, stavba a využití v sólové, komorní a orchestrální hudbě" pojednává o pikole, nástroji příbuzném příčné flétně. První kapitola seznamuje čtenáře s historií jak příčné flétny, tak pikoly. Věnuje se popisu konstrukčních změn a funkce nástrojů od nejstarších dob až po současnost.
Ve druhé kapitole se zaměřuji pouze na pikolu, na její stavbu, materiály, ze kterých může být vyrobena (kov, dřevo). Zároveň uvádím významné světové výrobce pikoly a pozornost věnuji i péči o tento nástroj. Třetí kapitola pojednává o možnostech využití pikoly, a to jako sólového nástroje, člena komorního souboru nebo součást symfonického či operního orchestru.The bachelor's thesis "Picollo. Its Historical Development, Construction and Use in Solo, Chamber and Orchestral Music." is concerned with a picollo, an instrument related to the flute. The first chapter introduces the history of both the flute and the picollo to the reader. It also includes the description of constructional changes of the instruments and their functions from the beginnings until the present day.
In the second chapter, the author focused only on the picollo, its construction and the materials it may be made of (metal, wood). The author also mentioned the significant international producers of picollos and attention was also paid to the maintenance of the instrument. The last chapter examines the possibilities of picollo's use as a solo instrument or as a member of a chamber, symphonic or operatic orchestra
La progettazione dello spazio liturgico. Concorso nazionale per tre nuovi complessi parrocchiali
No full textIl libro riporta tutti i progetti che hanno partecipato al concorso nazionale per tre nuovi complessi parrocchiali collocati in tre differenti aree di Milano e provincia, unitamente a testi di: Card. Carlo Maria Martini, Mons. Giuseppe Arosio, Renato Peduzzi, Giorgio Trebbi, Paolo Portoghesi, Vittorio Gregotti, Lodovico Barbiano di Belgiojoso, Giuseppe Varaldo, Demetrio Costantin
Functional Modifications Induced via X-ray Nanopatterning in TiO2 Rutile Single Crystals
No full textThe possibility to directly write electrically conducting channels in a desired position in rutile TiO2 devices equipped with asymmetric electrodes—like in memristive devices—by means of the X-ray nanopatterning (XNP) technique (i.e., intense, localized irradiation exploiting an X-ray nanobeam) is investigated. Device characterization is carried out by means of a multitechnique approach involving X-ray fluorescence (XRF), X-ray excited optical luminescence (XEOL), electrical transport, and atomic force microscopy (AFM) techniques. It is shown that the device conductivity increases and the rectifying effect of the Pt/TiO2 Schottky barrier decreases after irradiation with doses of the order of 1011 Gy and fluences of the order of 1012 J m−2. Irradiated regions also show the ability to pin and guide the electroforming process between the electrodes. Indications are that XNP should be able to promote the local formation of oxygen vacancies. This effect could lead to a more deterministic implementation of electroforming, being of interest for production of memristive devices
Penetration of prulifloxacin into sinus mucosa of patients undergoing paranasal sinus elective endoscopic surgery
No full textThe aim of this study was to assess the concentration of ulifloxacin, the active metabolite of prulifloxacin, in sinuses mucosa and plasma of patients with chronic rhinosinusitis, requiring sinus elective endoscopic surgery. Thirty-nine patients (30 males, 9 females; age range 22-77 years) with chronic sinusitis were enrolled, 35 were treated with the investigational medication. Samples from four untreated patients were used to validate the analytical method, while four treated patients dropped out before surgery. One 600 mg prulifloxacin tablet once daily was administered for 5 days before surgery. The last dosing was scheduled from 2 to 12 hours from tissue and plasma sampling. In each patient, two samples of paranasal sinus mucosa (from ethmoid and turbinate, respectively) and one blood sample were collected. Concentrations of ulifloxacin in plasma and sinuses mucosa were measured using validated bioanalytical LC/MS/MS methods. Individual and mean ulifloxacin concentrations in tissues were always higher than the relevant plasma levels. The highest concentrations were observed between 2·5 and 4·5 hours after the last dosing in all districts. The mean tissue/plasma ratios were 2·5 and 3·0 for ethmoid and turbinate, respectively. Data expressed as Area Under the Curves (AUC±SD) showed that ulifloxacin concentrations in the ethmoid were slightly higher (18·68±6·48 μg/g*h) than in turbinate (15·00±2·89 μg/g*h), and definitely higher than in plasma (6·32±1·14 μg/ml*h). The AUC ratios between tissues and plasma were 3·0 for ethmoides and 2·4 for turbinates. One patient reported two treatment-related episodes of diarrhea, which spontaneously resolved after the drug suspension. Results from this study seem to suggest that prulifloxacin showed good distribution in sinus tissues, where it reaches concentrations significantly higher than in plasma. These findings strongly call for confirmatory clinical trials in patients with bacterial rhinosinusitis
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