170,024 research outputs found
DEM and FEM/DEM Modelling of Granular Flows to Investigate Large Debris Avalanche Propagation
No full textLarge debris avalanches are characterized by extremely rapid, flow-like motion of large masses and they travel extremely long distances showing much greater mobility than could be predicted using frictional models. In order to investigate the mechanisms involved and the reasons for the large propagation of these phenomena a discrete element model (DEM) and a combined finite and discrete element one (FEM/DEM) are used to simulate small-scale laboratory experiments carried out by Manzella “Manzella and Labiouse (Rock Mech Rock Eng 41(1):133–151, 2008, Eng Geol 109(1–2):146–158, 2009, Landslides, 2011 submitted); Manzella (Dry rock avalanche propagation: unconstrained flow experiments with granular materials and blocks at small scale. Ph.D. n 4032, Ecole Polytechnique Fe´de´rale de Lausanne, Lausanne,CH, 2008)”. The combined use of different models produces amore complete study of the phenomena since each model can fill certain gaps of the other; they also help in a better understanding of some mechanisms and factors, which are important in the longitudinal propagation of granular and block flows, such as the progressive failure, the initial block packing and the topographical characteristics of the slope break
Positive autoregulation of c-myb expression via myb binding sites in the 5' flanking region of the human c-myb gene
No full textThe nuclear proto-oncogene c-myb is preferentially expressed in lymphohematopoietic cells, in which it plays an important role in the processes of differentiation and proliferation. The mechanism(s) that regulates c-myb expression is not fully understood, although in mouse cells a regulatory mechanism involves a transcriptional block in the first intron. To analyze the contribution of the 5' flanking sequences in regulating the expression of the human c-myb gene, we isolated a genomic clone containing extensive 5' flanking sequences, the first exon, and a large portion of the first intron. Sequence analysis of a subcloned 1.3-kb BamHI insert corresponding to 687 nucleotides of the 5' flanking sequence, the entire first exon, and 300 nucleotides of the first intron revealed the presence of closely spaced putative Myb binding sites within a segment extending from nucleotides -616 to -575 upstream from the cap site. A 165-bp segment containing these putative Myb binding sites was linked to a human thymidine kinase (TK) cDNA driven by a low-activity proliferating cell nuclear antigen promoter and cotransfected into TK- ts13 cells with a plasmid in which a full-length human c-myb cDNA is driven by the early simian virus 40 promoter; Myb inducibility of TK mRNA expression was observed both in transient expression assays and in stable transformants. The highest level of inducibility was detected when the 165-bp fragment was placed 138 bp upstream of the proliferating cell nuclear antigen promoter-TK cDNA reporter unit or 3' of the TK cDNA. Mutation of the putative Myb binding sites greatly reduced c-myb transactivation of TK mRNA expression and specifically reduced the binding of in vitro-translated Myb protein at those sites. Finally, c-myb transactivated TK mRNA expression driven by a segment of the authentic c-myb 5' flanking region containing the Myb binding sites. These data suggest that human c-myb maintains high levels of Myb protein in cells that require this gene product for proliferation and/or differentiation by an autoregulatory mechanism involving Myb binding sites in the 5' flanking region
TOWARDS THE INTEGRATION OF MAGNETOTELLURIC WITH GEOLOGICAL SEISMIC AND GRAVITY DATA WITHIN THE SIRIPRO PROJECT
No full textAvidum mare nautis. Un naufragio nel porto di Odessus e altre iscrizioni
No full textIvan Di Stefano Manzella, Avidum mare nautis. Un naufragio nel porto di Odessus e altre iscrizioni, p. 79-106.
Si esaminano : 1) un carme epigrafico (IV sec.) che esalta l'impresa di Eusebius, dominus navium; egli, perduta la flotta, naufragata all'ingresso dei porto di Odessus (Mar Nero) per il crollo di un molo, ripristinò la navigazione togliendo i massi (scrupea) dal canale di accesso. 2) tre testi votivi : a) di M. Secundius Silvanus negotiator cretarius Britannicianus a Nehallenia (isola di Walkeren, Olanda) ob merces recte conservatas; b) di L. Licinius Divixtus ai Casses e alla Domus Divina (Württemb. Landesmus., Stuttgart) per aver nel 227 salvato la vita pos[t] summersam m(ercem); c) dei fratelli Libonii Mettus e Cracuna (mus. di Treviri) al Numen Augustum e al Genius proretarum, testo inciso sopra una prua in bronzo, già parte di una nave votiva lignea. 3) il testo sepolcrale dei cenotafio di un soldato anonimo, morto in un naufragio, e altre iscrizioni che ricordano viaggi per mare.Di Stefano Manzella Ivan. Avidum mare nautis. Un naufragio nel porto di Odessus e altre iscrizioni. In: Mélanges de l'École française de Rome. Antiquité, tome 111, n°1. 1999. pp. 79-106
The interferon regulatory factors 1 and 2 bind to a segment of the human c-myb first intron: possible role in the regulation of c-myb expression.
No full textThe preferential expression of the protooncogene c-myb in hematopoietic cells is in part regulated by a mechanism of transcriptional block in the first intron. By electrophoresis mobility shift assays using probes corresponding to different segments of the putative human c-myb intron 1 transcription pause region and nuclear extracts from myeloid leukemia HL 60 and fibroblast WI 38 cells, we detected a HL-60-specific DNA–protein complex with a 123-bp fragment containing binding sites for the interferon regulatory factors (IRFs) nuclear proteins. Formation of the DNA–protein complex was abrogated by competition with an oligomer containing the wild-type, but not the mutated, IRF binding site and the complex was specifically supershifted by the anti-IRF-1 or the anti-IRF-2 antibody. Moreover, in vitro translated IRF-1 or IRF-2 protein did interact with the 123-bp c-myb intron 1 fragment. Upon TPA-induced differentiation, c-myb expression was readily down-modulated in parental HL 60 cells, but not in cells transfected with an antisense IRF-1 plasmid. Moreover, chloramphenicol acetyltransferase activity driven by a c-myb promoter containing the entire intron 1 was suppressed upon IRF-1, but not IRF-2 expression. Together, these results are consistent with the existence of a functional relationship between IRF-1 and c-myb in which IRF-1 negatively regulates c-myb expression at the transcriptional level by a mechanism that may depend on the interaction of IRF-1 with a segment of the c-myb gene implicated in transcription pausing
La sfida internazionale della Comit
No full textGli anni Ottanta del Novecento furono un periodo di intensi cambiamenti dell’economia mondiale, durante il quale si posero le premesse e maturarono le condizioni per l’avvio e il consolidamento dei fenomeni di globalizzazione dei mercati delle merci e dei capitali che hanno caratterizzato l’ultimo ventennio. Grande protagonista della storia economica e finanziaria italiana da quasi un secolo, la Banca Commerciale Italiana avviò prima di altri la propria strategia multinazionale con l’obiettivo di darsi rapidamente dimensioni almeno europee. Essa cercò inoltre di consolidare la propria presenza negli Stati Uniti e di trasformarsi in una dollar bank, in grado di operare su scala globale, anche se, da ultimo, il suo tentativo di acquisire la Irving Bank non si realizzò sia per gli ostacoli frapposti da parte americana sia per le chiusure dell’establishment politico-economico italiano. Il libro ripercorre quelle vicende, le luci e le ombre della difficile metamorfosi di una grande banca pubblica agli albori del processo di globalizzazione, cercando di chiarire le ragioni di successi e insuccessi della strategia internazionale della Comit in un periodo di cruciali cambiamenti per la nostra storia recente
Verify the position of implants in master casts for implant-supported prostheses with stone devices
No full textA method to improve passive fit of frameworks on implant-supported prostheses: an in vivo study
No full textA die stone jig was evaluated as to its ability to clinically verify the position of the abutment on the master cast. The jig detected misfits in clinical trials, according to the parameters defined in the literature
New insights from analyses of geophysical data in the Northern Apennine buried structures for evaluation of their geothermal potential
No full textGeothermal energy is arguably the most attractive of low-CO2 renewable resources, being broadly distributed and available in every period of the year. The main aim of the InGEO project (Innovation in GEOthermal resources and reserves potential assessment for the decarbonisation of power/thermal sectors) is to develop an innovative exploration workflow integrating geophysical data and other direct and indirect information, organized to make available a sort of decision support system of geothermal projects. To this purpose, we chose as a target area the Northern Apennine buried structures belonging to the Romagna and Ferrara Folds (RFF). This area extends from the termination of the Emilia Folds in the West to the Adriatic coast in the East and from the outcropping edges of the Northern Apennines in the South to the undeformed Po foredeep in the North. The RFF area has been the subject of previous geothermal studies revealing relatively low geothermal gradients within the deep carbonate units (on average 14 °C/km) and more significant thermal gradients (on average 53 °C/km) in the overlying impermeable formations (Pasquale et al., 2013). This feature in temperature distribution with depth is clear evidence for fluid thermal convection occurring in the deep seated carbonate units of Mesozoic age, which constitutes the local geothermal reservoir. The shallow crust of this area has been investigated by several previous studies and through a total of 535 deep exploratory
wells (VIDEPI database: https://www.videpi.com/videpi/videpi.asp), having final depths ranging from 0.5 up to 6.5 km below ground level. They provide essential information, concerning lithostratigraphy, temperatures measured during drilling stops and geophysical logs, commonly electrical resistivity, gamma ray and sonic. Several geophysical investigations, recently carried out in the Alps and Po plain, revealed both the shallow ad
deep structures of the study area, in terms of lateral variations of Bouguer anomalies, seismic velocities, and main discontinuities (Nouibat et al., 2023; Zahorec et al., 2021). The analyses of the data collected revealed a good correspondence between the low seismic velocities, characterizing the shallow crust of the RFF, and the negative Bouguer anomalies. We reconstructed the Moho depth of the area, estimating the depth of the iso velocity contour of 4.1 km/s (Nouibat et al., 2023) and observed its deepening from NE to SW, towards the Apennines, from ~27 km to ~48 km. Seismic tomography of the upper mantle (Rappisi et al., 2022) reveals that the velocity in the shallow and deep lithosphere is low in the central part of the study area, possibly related to a local asthenospheric upwelling and tends to increase beneath the Apennines. The results of this ongoing research will be the input of the thermal model and contribute to the development of an open-source and web
based GIS tool, and to the calculation of the deep geothermal energy potential for both hydrothermal resources and deep heat exchangers
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
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