322,852 research outputs found
Giuseppe Felloni e l'Archivio di Stato di Genova
No full textThe essay wants to outline the scientific and institutional relationships between Giuseppe Felloni and the State Archives of Genoa. It starts considering the activity of the economic history scholar from his attendance of the reading room, to the fulfillment of the reordering and description project of the Casa delle compere di San Giorgio archives. Is finally proposed a focus on Felloni’s personal papers preserved today in the same State Archives
A Graphic Representation of States for Quantum Copying Machines
No full textThe aim of this paper is to introduce a new graphic representation of quantum states by means of a specific application: the analysis of two models of quantum copying machines. The graphic representation by diagrams of states o®ers a clear and detailed visualization of quantum information's flow during the unitary evolution of not too complex systems. The diagrams of states are exponentially more complex in respect to the standard representation and this clearly illustrates the discrepancy of computational power between quantum and classical systems. After a brief introductive exposure of the general theory, we present a constructive procedure to illustrate the new representation by means of concrete examples. Elementary diagrams of states for single-qubit and two-qubit systems and a simple scheme to represent entangled states are presented. Quantum copying machines as imperfect cloners of quantum states are introduced and the quantum copying machines of Griffiths and Niu and of Buzek and Hillery are analyzed, determining quantum circuits of easier interpretation. The method has indeed shown itself to be extremely successful for the representation of the involved quantum operations and it has allowed to point out the characteristic aspects of the quantum computations examined
Effects of single-qubit quantum noise on entanglement purification
No full textWe study the stability under quantum noise effects of the quantum privacy amplification protocol for the purification of entanglement in quantum cryptography. We assume that the E91 protocol is used by two communicating parties (Alice and Bob) and that the eavesdropper Eve uses the isotropic Bu (z) over bar ek-Hillery quantum copying machine to extract information. Entanglement purification is then operated by Alice and Bob by means of the quantum privacy amplification protocol and we present a systematic numerical study of the impact of all possible single-qubit noise channels on this protocol. We find that both the qualitative behavior of the fidelity of the purified state as a function of the number of purification steps and the maximum level of noise that can be tolerated by the protocol strongly depend on the specific noise channel. These results provide valuable information for experimental implementations of the quantum privacy amplification protocol
High Cycle corrosion-fatigue cack propagation behaviour of API 5L-X65 steel in salt water.
No full textPer un territorio di imprese resilienti
No full textRispetto all’attuale scenario di esposizione e diffusa fragilità del nostro Paese, la diminuzione sensibile e quantificabile dei danni e delle perdite di beni economici e alle imprese costituisce uno degli obiettivi prioritari individuati nell'ambito delle strategie del prossimo futuro di riduzione dei rischi da disastri naturali (Accordo di Sendai, 2015-2030). In questo senso, i concetti di adattamento e resilienza richiedono alle culture e alle pratiche di pianificazione territoriale e di progettazione urbanistica di dotarsi – alle differenti scale – di specifici strumenti e metodi a supporto delle capacità dei territori di assorbire eventi calamitosi e riorganizzarsi in modo da recuperare le proprie funzioni, strutture e relazioni. Nella cornice di queste argomentazioni il contributo porta alla riflessione comune alcuni esiti del progetto ‘Osservatorio Imprese Resilienti’ della Provincia di Piacenza che ha inteso porre le basi per l’osservazione del sistema economico-territoriale piacentino dal punto di vista della resilienza ai rischi meteo-climatici, dando anche avvio a un percorso di conoscenza, sensibilizzazione e consolidamento della rete locale dei portatori di interesse. Nello specifico, mediante l’utilizzo di un innovativo sistema di mappatura che prevede l’uso integrato di dati solitamente utilizzati per analisi economico-finanziarie (Database AIDA) e di informazioni su aree potenzialmente allagabili (mappature AdBPo), viene condotta un’analisi spaziale rappresentativa dei caratteri e dei valori territoriali piacentini e della loro esposizione al rischio rispetto cui individuare specifiche strategie di mitigazione e adattamento
Diffusive author(s), cohesive author: Analysis of S/N (1994)
No full textThis study indicates the ways in which various aspects of the author(s) are brought forth in Dumb type’s performance art, the S/N production. Previous research has suggested a non-hierarchical organization of Dumb type and the absence of a “privileged author” in Dumb type’s collaborative work, S/N. However, the results that I have investigated from member’s interviews on the creative process of S/N along with my analysis of the recorded images of S/N, indicate a different aspect of the author(s). First, S/N was created through, so to speak, the collective ideas of the members of Dumb type. Further, S/N has at least nine quotations from previous performances, installations, and printed writings, besides the work-in-progress technique. Explicating one of the “author functions” as given by Michel Foucault, each text has plural subjects of the author. However, it has been revealed from members’ interviews that Teiji Furuhashi had a decision-making role in selecting the members’ ideas within the performance. Since then, S/N has had plural subjects of creation; however, Furuhashi is one of the subjects of creation along with the “privileged author.” S/N has plural authors (diffusive authors) yet at the same time, it has a “privileged author,” Teiji Furuhashi (cohesive author)
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Salivary mutans streptococci and lactobacilli in 9- and 13-year-old Italian schoolchildren and the relation to oral health
No full textThe prevalence and levels of mutans streptococci (MS) and lactobacilli (LB) in saliva and its possible correlation with dental caries and periodontal conditions was investigated in 473 Italian schoolchildren, 9 and 13 years of age. A clinical examination and sampling of stimulated whole saliva was carried out in the school and oral health was assessed as DMFT and CPITN using the WHO criteria. The saliva samples were frozen in liquid nitrogen and after thawing, cultivated on selective media. To test the influence of cryopreservation, fresh samples from 20 subjects were cultivated. Thirty-five percent of the children were caries-free with a mean DMFT of 1.9 at the age of 13. The majority exhibited healthy periodontal conditions. Salivary MS and LB were identified in 52% and 21% of the children, respectively. The prevalence of MS was higher among the 13-year-olds than the 9-year-olds while no such difference was found regarding LB. There was a statistically positive relationship (P < 0.01) between the levels of MS and LB and both were significantly correlated to caries (P < 0.01). The correlation coefficient of microbial recovery between frozen and unfrozen samples was 0.99. In conclusion, the data provided cross-sectional information of a clear positive relationship between selected micro-organisms in saliva and caries in 9- and 13-year-old children in spite of a relatively low prevalence of the disease. The findings are discussed in a risk selection perspective
The effect of surface roughness on early in vivo plaque colonization on titanium
No full textThis study assesses in vivo the surface roughness necessary to reduce plaque colonization on titanium after 24 hours. Three groups of 16 titanium disks were assigned to 3 different polishing groups (A, B, and C). The roughness was evaluated with a laser profilometer and the morphology with a scanning electron microscope (SEM). Eight volunteers were enrolled and two stents were applied in the mandibular posterior region of each. Each stent supported 3 disks, one per group. The volunteers suspended oral hygiene for 24 hours, after which the stents were removed; one was processed for evaluation of the adherent biomass and the other for SEM study. On each specimen a global area of 100 x 125 μm was examined with SEM. The area was composed of five 20 x 25 μm randomly selected fields. For each field the density of bacteria and the morphotypes were recorded. The data quoted for the global area are cumulative of those observed in the 20 x 25 μm fields. Group A had a significantly smoother surface than groups B and C. The adherent microbial biomass determination and SEM evaluation revealed that group A contained less bacteria than the roughest group. The bacterial population was composed of cocci in group A, and of cocci and short and long rods in groups B and C. We conclude that a titanium surface with Ra ≤ 0.088 μm and Rz ≤ 1.027 μm strongly inhibits accumulation and maturation of plaque at the 24-hour time period and that such smoothness can be achieved in transgingival and healing implant components
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