1,288 research outputs found
Ex Carceri di San Pancrazio a Cagliari: scavi e restauri per la rifunzionalizzazione dal 1986 al 2006
Ex Carceri di San Pancrazio a Cagliari: scavi e restauri per la rifunzionalizzazione dal 1986 al 2006
Lo studio proposto si Ăš occupato delle mura urbane di Cagliari, con particolare attenzione allâarea nord del quartiere storico di Castello, ovvero lâarea di San Pancrazio. Le indagini bibliografiche e archivistiche hanno permesso di ricostruire la storia e lâevoluzione architettonica di alcuni manufatti storici di questâarea, concentrando lâattenzione sul cosiddetto âSpazio San Pancrazioâ, area attualmente espositiva ottenuta dallo svuotamento del Baluardo cinquecentesco del Dusay.
I restauri che hanno permesso lâeffettivo utilizzo di questo Spazio sono stati condotti dal 1986 al 2006 a cura della Soprintendenza ai Beni B.A.A.A.S. e hanno consentito di recuperare lâintera volumetria contenuta allâinterno del baluardo, liberata dal riempimento di terra aggiunto in epoca spagnola, con la messa in luce dellâintero avancorpo fortificato della torre e delle stratificazioni dal periodo pisano a quello piemontese. Il ârovescioâ della cortina difensiva medioevale cosĂŹ emerso ha definito un nuovo volume architettonico di ben 780 mq.
Ă stato di notevole interesse scoprire lâoriginaria soluzione costruttiva che si ritrovĂČ perfettamente conservata al momento dello scavo. Questa consisteva in una struttura composta da setti murari paralleli che, collegati da volte, correvano lungo il perimetro del baluardo.
Tutte le informazioni raccolte durante la ricerca sono state sistematizzate attraverso lâimplementazione del sistema informativo del MIBACT, SICaR/web. La ricerca, confluita in un lavoro di tesi di laurea, ha avuto un immediato riscontro da parte della comunitĂ scientifica locale. Infatti, ha reso disponibile il materiale documentario, per la prima volta riordinato, georeferenziato e reso consultabile attraverso il portale ministeriale SICaR/web.
Lâoccasione del riordino documentale ha portato alla redazione di attendibili schedature informatizzate anche sul sistema ministeriale SIGEC/web, allora in fase di test nazionale, avendo cosĂŹ un riscontro tra luci e ombre dei due sistemi informativi ministeriali per i BB.CC
Sequential biological and photocatalysis based treatments for shipboard slop purification: A pilot plant investigation
This study investigated the treatment of a shipboard slop containing commercial gasoline in a pilot plant scale consisting of a membrane biological reactor (MBR) and photocatalytic reactor (PCR) acting in series. The MBR contributed for approximately 70% to the overall slop purification. More precisely, the biological process was able to remove approximately 40%, on average, of the organic pollution in the slop. Nevertheless, the membrane was capable to retain a large amount of organic molecules within the system, amounting for a further 30% of the influent total organic content removal. However, this affected the membrane fouling, thus resulting in the increase of the pore blocking mechanism that accounted for approximately 20% to the total resistance to filtration (2.85â10 13 m â1 ), even if a significant restoration of the original membrane permeability was obtained after chemical cleanings. On the other hand, the biological treatment produced a clear solution for the photocatalytic system, thereby optimizing the light penetration and generation of highly oxidizing active oxygen species that enabled the degradation of bio-recalcitrant compounds. Indeed, low total organic carbon (TOC) values (<10 mg L â1 ) were achieved in the output of the photocatalytic reactor by means of only 60 Einstein (E) of cumulative impinging energy after the addition of K 2 S 2 O 8 . Overall, coupling the two processes enabled very high TOC removal (ca. 95%)
Generation of synthetic wide-band electromagnetic time series
The estimation of the earth transfer functions in MT prospecting method poses the greatest difficulty. As in the seismic prospecting method this task requires the development of advanced processing techniques. In order to assess the performance of each technique, controlled synthetic data and different noise types, which simulate the observed signals, are required. This paper presents a procedure to generate a wide-band noise-free electromagnetic field to be used both for magnetotelluric and audio-magnetotelluric studies. Furthermore, an effort was made to extend the simulation procedures to generally stratified and simple inhomogeneous earth structures. The discrete-time magnetic field values are generated through the inverse Fourier transform of a continuous amplitude spectrum and a sampling procedure. The electric field time series are obtained by the convolution of the magnetic field time series, calculated in the interested frequency band, with a non-causal impedance impulse response. Polarized fields, which are important when inhomogeneous media are considered, are also generated
Generation of synthetic wide-band electromagnetic time series
The estimation of the earth transfer functions in MT prospecting method poses the greatest difficulty. As in the seismic prospecting method this task requires the development of advanced processing techniques. In order to assess the performance of each technique, controlled synthetic data and different noise types, which simulate the observed signals, are required. This paper presents a procedure to generate a wide-band noise-free electromagnetic field to be used both for magnetotelluric and audio-magnetotelluric studies. Furthermore, an effort was made to extend the simulation procedures to generally stratified and simple inhomogeneous earth structures. The discrete-time magnetic field values are generated through the inverse Fourier transform of a continuous amplitude spectrum and a sampling procedure. The electric field time series are obtained by the convolution of the magnetic field time series, calculated in the interested frequency band, with a non-causal impedance impulse response. Polarized fields, which are important when inhomogeneous media are considered, are also generated
Nanochemistry aspects of titania in dye-sensitized solar cells
We analyze the main nanochemistry factors affecting photovoltaic performance in TiO2 employed as wide bandgap semiconductor in dye-sensitized solar cells (DSCs). What is the best morphology of the oxide? Which processes yield the required structures? Finally, putting the discussion in the context of the rapid evolution of photovoltaic technologies, we argue that new titania nanostructures will form the basic component of second-generation solar modules based on dye solar cells
Photocatalytic degradation of dyes by using a membrane reactor
Dyes are organic compounds used in textile, food and drug industries, and their abatement represents one of the main problems in the treatment processes because generally they are very stable toxic compounds. In this work, two commercial azo-dyes, i.e. Congo Red (C32H22N6Na2O6S2) and Patent Blue (C27H31N2NaO6S2), in aqueous solution were degraded in a photocatalytic membrane reactor by using TiO2 Degussa P25 as the catalyst. Different system con\ufb01gurations and irradiating sources were studied, and the in\ufb02uence of some operational parameters such as the pressure in the membrane cell and the initial concentration of the substrates was determined. A comparison between suspended and entrapped TiO2 was also done. The experimental results showed a satisfactory degradation ef\ufb01ciency of the photocatalytic membrane process. The in\ufb02uence of various parameters (e.g. feed concentration, recirculation rate) has been discussed to obtain high reaction rates, operating stability and high membrane rejection, both for substrates and by-products. Congo Red was photodegraded with higher rate under the same experimental conditions probably due to its higher adsorption onto the catalyst surface. It was possible to treat successfully highly concentrated solutions (500 mg/L) of both dyes by means of a continuous process obtaining good values of permeate \ufb02uxes (30\u201370 L/m2 h); this could be interesting for industrial applications. The reactor containing the suspended photocatalyst was signi\ufb01cantly more ef\ufb01cient than the reactor containing the catalyst entrapped into the membrane
Immunhistochemische Detektion von Komponenten des Gewebs-Kallikrein-Kinin-Systemsin Testis und Epididymis verschiedener Spezies
Neben dem systemischen Plasma-Kallikrein-Kinin-System kommt nahezu ubiquitĂ€r eine gewebsspezifische Variante vor, die physiologische und pathologische Prozesse im Körper von SĂ€ugetieren beeinflusst. Aus inaktiven VorlĂ€uferproteinen (Kininogenen) setzt Gewebs-Kallikrein das Peptidhormon Bradykinin frei, welches ĂŒber spezifische membranstĂ€ndige Rezeptoren seine physiologische Funktion ausĂŒbt.PrimĂ€res Ziel dieser Dissertation war die genaue topographische und zellspezifische Lokalisierung der Protease Gewebs-Kallikrein im mĂ€nnlichen Reproduktionstrakt verschiedener SĂ€ugerspezies mit Hilfe immunhistochemischer Techniken.Im Rattentestis wurde Gewebs-Kallikrein stadienspezifisch an der akrosomalen Kappe runder und elongierter Spermatiden nachgewiesen, nicht jedoch an Spermien im Lumen von Hoden oder Nebenhoden. Möglicherweise ĂŒbt diese Protease hier  neben seiner klassischen Rolle im KKS - auch eine Funktion beim Ablösen der Spermien von den Sertoli-Zellen (Spermiation) aus. Gewebs-Kallikrein im Hoden des Bullen zeigte im Wesentlichen die gleiche Lokalisation. Leider gelang beim humanen Testis trotz vielfĂ€ltiger Variation der Methode kein eindeutiger Nachweis von Gewebs-Kallikrein.Im Nebenhoden der Ratte wurde Gewebs-Kallikrein im Bereich des Corpus und Cauda sowie im Ductus deferens detektiert. Das sehr inhomogene Verteilungsmuster entspricht wahrscheinlich dem unterschiedlichen AktivitĂ€tsniveau der Epithelzellen im Sinne einer Sekretion dieser Protease. Möglicherweise wird Gewebs-Kallikrein hier zunĂ€chst basal des Nukleus produziert, danach in den apikalen Bereich der Epithelzelle verlagert und dann als vesikulĂ€re AbschnĂŒrung sezerniert. Apikale AbschnĂŒrungen an Epithelzellen von Nebenhodengang und Ductus deferens zeigten ebenfalls eine positive FĂ€rbung fĂŒr Gewebs-Kallikrein. Kallikrein zeigte sich weiterhin zytoplasmatisch in den Muskelzellen der Wandung des Ductus epididymis bzw. Ductus deferens und der GefĂ€Ăe. Im Epididymis könnte daher Gewebs-Kallikrein bzw. das KKS bei der Reifung der Spermatozoen eine Rolle spielen.Anhand von Gewebeschnitten, die aus Ratten unterschiedlicher Altersstufen angefertigt wurden, zeigte sich eine ausgeprĂ€gte AbhĂ€ngigkeit des Auftretens von Gewebs-Kallikrein vom sexuellen Entwicklungsstand des Tieres. Im Testis trat diese Protease erst mit Beginn der PubertĂ€t und dem damit verbundenen erstmaligen Durchlaufen des Spermatogeneszyklus mit der Bildung von zunĂ€chst runden und zeitlich spĂ€ter elongierten Spermatiden auf. Im Nebenhoden erfolgte die Produktion und Sekretion von Gewebs-Kallikrein in Epithelzellen erstmals mit dem Auftreten von Spermien im Tubulussystem kurz nach der ersten Spermiation.LMW-Kininogen, als Substrat des Gewebs-Kallikreins, wurde an der sich entwickelnden Akrosomenkappe runder und elongierter Spermatiden von Mensch und Bulle nachgewiesen, nicht jedoch an ins Lumen liberierten Spermatozoen. Auch im interstitiellen Stroma zeigte sich eine spezifische FĂ€rbung.Der Antikörper gegen die Neutrale Metalloendopeptidase (CALLA) erbrachte am humanen und bovinen Reproduktionsgewebe keinen positiven Nachweis. In humanem Gewebe zeigten dagegen einzelne Zellen des retikulohistiozytĂ€ren Systems eine positive Farbreaktion.Die hier gezeigte selektive, stadienspezifische (Testis) und entwicklungsabhĂ€ngige (Testis, Epididymis) Expression der Protease Gewebs-Kallikrein in bestimmten Zelltypen sowie Regionen (Epididymis) deutet auf eine Beteiligung des Gewebs-KKS am ProzeĂ der Differenzierung und Reifung von Spermatozoen.Local production of kinins occurs in many tissues by the action of tissue kallikrein on the precursor low-molecular weight kininogen. The various physiological and pathological functions of kinins are mediated by specific membrane-bound receptors. Several lines of evidence point to a possible involvement of the tissue kallikrein-kinin system in male reproduction.In this thesis, the exact topographic and cellular localization of the protease tissue kallikrein (tK) in male reproductive organs of different species was investigated using immune histochemistry.Within the seminiferous tubules of mature rat and bull testes, tissue kallikrein was solely detected in round and elongated spermatids, where it was associated with the acrosomal cap. In contrast, liberated spermatozoa within the lumen did not show positive staining for tK. Tissue kallikrein was expressed in all tubules, but the staining pattern was dependend on the developmental stage of the spermatogenic cycle. In the interstitium, tK was present in endothelial and muscle cells of blood vessels, but not in Leydig cells.In the rat, tK showed a development-dependent expression. Within the testes, it was first detected with the onset of spermatogenesis on step 5 spermatids at day 28 after birth: in the epididymis it first occurred shortly after spermiation at day 38.Tissue kallikrein showed an inhomogeneous distribution in the epithelial cells of the rat epididymis located in the different areas of the corpus and cauda epididymis, as well the ductus deferens. The observed variations in the expression level may mirror the functional state of the epithelium. Tissue kallikrein seems to be produced in the basal compartment of the epithelial cells and than relocated to the apical part. Thereafter, apocrine secretion of tK within cytoplasmatic constrictions towards the lumen was detected. Tissue kallikrein was also localized in muscle cells of the vascular walls of the ductus epididymis and ductus deferens and blood vessels.LMW kininogen, the inactive precursor tK, was detected in the acrosomal cap of round and elongated spermatids in human and bovine testes, but not in liberated spermatozoa within the lumen. Peritubular and muscle cells as well as stroma were positive for kininogen.The antibody against the neutral metalloendopeptidase (CALLA) did not succeed at the human and bovine reproductive tissue. In the human tissue were only cells of the reticulohistiocytic system positiv for CALLA.The stage- and developmental expression of tissue kallikrein in developing germ cells and the epithelial cells of the epididymis suggests a potential role of the tissue kallikrein-kinin system in the local regulation of spermatogenesis and sperm maturation
Enhancing H2 production rate in PGM-free photoelectrochemical cells by glycerol photo-oxidation
The photo-oxidation of glycerol was carried out by using TiO2 NTs photoanodes and Ni foam as the cathode for the Hydrogen Evolution Reaction. The photoanodes were prepared by anodizing Ti foils and titanium felt and then annealed under air exposure. They were tested in acidic aqueous solution without and with the addition of glycerol. When glycerol was present, the hydrogen production rate increased and allowed the simultaneous production of high value added partial oxidation compounds, i.e. 1,3-dihydroxyacetone (DHA), and glyceraldehyde (GA). The highest H2 evolution and partial oxidation compounds production rates were obtained by using home prepared TiO2 nanotubes (TiO2 NTs) synthesized on Ti fiber felt as the photoanode with an irradiated area of 90 cm2. These photoanodes were found to be highly stable both from a mechanical and a chemical point of view, so they can be reused after a simple cleaning step
Shallow to intermediate resistivity features of the Colfiorito Fault System inferred by DC and MT survey
Over the last decade electromagnetic (EM) measurements have provided new constraints on the upper-crustal
structure of the major fault zones in the world, both when they act as conduit and as a barrier, due to strong sensitivity
of resistivity to fluids circulation and mineralization. On the track of a high impact magnetotelluric (MT)
study performed across the San Andreas Fault, high resolution EM data were collected in the Colfiorito epicentral
area along profiles crossing some main fault lineaments. Being the study focussed both on shallow that on intermediate
resistivity distribution in the brittle upper-crust, a MT profile was integrated by several electrical resistivity
tomographies (ERT). The latter were successful in locating faults even where the structures are buried by a wide
covering of Quaternary deposits and in the recognition of different electrical signatures of the faults. MT resistivity
model crossing Mt. Prefoglio normal fault clearly imaged the typical thrust structures of the area and a high
conductive zone spatially related to the fault. Seismicity seems to be located outside such conductive area, whose
behaviour suggests a fluidised and altered zone incapable of supporting significant stress internally
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