2,556 research outputs found
La sequenza stratigrafica, Catalogo (con A. Ruta Serafini), Note conclusive (con A. Ruta Serafini)
No full textVengono presentati i risultati di un intervento di archeologia di emergenza effettuato nella necropoli orientale di Padova, che ha portato al recupero di 26 sepolture di VI sec. a. C
PGPDT: Parallel Gradient Projection-based Decomposition Technique
No full textGPDT is a C++ software designed to train large-scale Support Vector Machines (SVMs) for binary classification in both scalar and distributed memory parallel environments [1,3,5,6]. It uses a popular problem decomposition technique to split the SVM quadratic programming (QP) problem into a sequence of smaller QP subproblems, each one being solved by a suitable gradient projection method (GPM). The currently implemented GPMs are the Generalized Variable Projection Method (GVPM) [2] and the Dai-Fletcher method (DFGPM) [4]. [1] G. Zanghirati, L. Zanni, A Parallel Solver for Large Quadratic Programs in Training Support Vector Machines, Parallel Computing 29 (2003), 535-551.[2] T. Serafini, G. Zanghirati, L. Zanni, Gradient Projection Methods for Large Quadratic Programs and Applications in Training Support Vector Machines, Optim. Meth. Soft. 20 (2005), 353-378.[3] T. Serafini, L. Zanni, On the Working Set Selection in Gradient Projection-based Decomposition Techniques for Support Vector Machines, Optim. Meth. Soft. 20 (2005), 583-596.[4] Y.H. Dai, R. Fletcher, New Algorithms for Singly Linearly Constrained Quadratic Programming Problems Subject to Lower and Upper Bounds, Math. Prog. 106(3) (2006), 403-421. [5] L. Zanni, An Improved Gradient Projection-based Decomposition Technique for Support Vector Machines, Computational Management Science 3(2) (2006), 131-145.[6] L. Zanni, T. Serafini, G. Zanghirati, Parallel Software for Training Large Scale Support Vector Machines on Multiprocessor Systems, JMLR 7(Jul), 1467-1492, 2006
Innovation in regional context: the case of Emilia-Romagna
No full textThe author builds upon the vast literature on the notion of
“knowledge economy” in order to describe and analyze recent transformations in the dynamics of innovation in Europe. He focuses on the emergence of new “regional systems”, in which regions become crucial institutions that mediate between industrial districts and the broader context of the new global economy. Serafini uses the Italian region of Emilia-Romagna – whose productive system is characterized by a remarkable innovative capacity – as an exemplary case-study. He
thus reconstructs the postwar tradition of industrial districts in this region, describes the limits of this form of organization, and sketches some of the salient aspects of the more recent transformations. The current phase is characterized by the active engagement of local administrations in fostering a close interaction between regional research centers and industries. This new model of regional system, and the
new innovation processes that characterize it, cannot be properly understood through traditional economic and statistical approaches, Serafini argues. Instead, these tools need to be integrated with qualitative methods that enable the analyst to map and interpret the structural
and historical features of the system as well
TRANSGLUTAMINASES IN SENESCENCE AND PROGRAMMED CELL DEATH OF LEAVES AND PETALS: THEIR SIMILARITIES TO ANIMAL TRANSGLUTAMINASES
No full textFree polyamines (PAs) have a contrasting role in the delay of senescence in animals, whereas in plants its protective effect is better established, eventhough the molecular mechanism is not clarified. We hypothesised that PAs can be conjugated to specific proteins by catalysis of Ca++-dependent transglutaminases (TGases). TGases are involved in PCD in animals, whereas few data are available in plants. Plants utilized were: Nicotiana tabacum corolla, models of short-lived flowers and Lactuca sativa leaves, commercially utilised for food purposes. Many morphological and physiological parameters were examined.
The supply of spermine (SM) to excised flowers or entire plant efficiently delayed senescence and PCD in petals or leaves respectively. SM caused an increase also of putrescine (PU) and spermidine (SD) levels. Only in senescent plants a new TGase band was immunodetected and, in concomitance, high molecular mass and other protein bands were PA-modified. During senescence mainly mono-, bis-PU and bis-SD catalysis increased. This data suggests that the protective effect of PAs could be mediated by TGase. SM effect on the retention of leaf proteins and chlorophylls was analysed in Valeriana young and senescent plants. Most of chlorophyll is bound to the antennae of light-harvesting complexes (LHC), known preferential thylakoid TGase substrates under light2. In Valeriana LHC enriched fractions, different TGase isoforms, immunologically related to TGases of animal origin, were co-purified. PA conjugation to both photosystems was light-stimulated.
The capacity of plants to express animal TGases and the similarities in the TGase sequences and activity in animals and plants have also been explored. Rat TGase (DP1 ORF) introduced into mature rice embryos by bombardment was expressed by the plant. It is Ca2+-dependent and active in in vitro assay, showing that plants could produce functional mammalian TGases3. Thylakoid TGase recognises animal substrates as well as animal TGases plant substrates, but only the plant TGase/plant substrate catalysis is light regulated2.
As in both the investigated senescence models any TGase has been fully-purified until now, another approach was undertaken. On the basis of the identification of a TGase-like domain in an A. thaliana gene, AtPng1p, we have cloned its codifying sequence on E. coli and purified the over-expressed recombinant protein. All biochemical assays showed a clear Ca++, pH, and DTT dependent TGase activity. This TGase was immunodetected by three antibodies raised against animal TGases. Data and bio-informatic analysis also suggest a possible protease activity for this first plant sequenced TGase4.
1 D Serafini-Fracassini, S Del Duca, F Monti, F Poli, G Sacchetti, AM Bregoli, S Biondi and M Della Mea (2002) -Transglutaminase activity during senescence and programmed cell death in the corolla of tobacco (Nicotian a tabacum) flowers. Cell Death and Diff. 9 (3) 309-321.
2 M. Della Mea, A. Di Sandro, L. Dondini, S. Del Duca, F.Vantini, C.Bergamini, R. Bassi and D. Serafini-Fracassini - A Zea mays 39 kDa thylakoidal transglutaminase catalyses the modification by polyamines of light harvesting complex II in a light-dependent way. Planta, in press. DOI 10.1007/s00425-004-1278-6
Ripensare la lacuna. Architettura e arti figurative nel XXI secolo
No full textQuali sono le nuove frontiere del restauro in merito al trattamento della lacuna architettonica e delle arti figurative? La ricerca di Dottorato analizza in àmbito internazionale le attuali modalità di intervento con il fine di comprendere i princìpi teorici – se esistenti - alle base delle scelte reintegrative della lacuna in relazione alle riflessioni scaturite dal dibattito contemporaneo tra i sostenitori di tre differenti orientamenti coesistenti: quelli della Teoria del restauro di Cesare Brandi, ampiamente diffusa nei Paesi di lingue neolatine, quelli della cosiddetta “teoria contemporanea del restauro” proposta dal restauratore spagnolo Salvador Muñoz Viñas, dominante nei Paesi anglosassoni, e i promotori del più recente approccio basato sul living heritage, radicato nei Paesi del Sud-Est asiatico e dell’Africa e in alcuni contesti dell’America latina e recentemente adattato al patrimonio culturale europeo dalla nascente Teoria Narrativa.
A partire dagli anni Ottanta del XX secolo ha avuto inizio il cambiamento della concezione eurocentrica della conservazione e del restauro, scandito dalla redazione di eminenti documenti come la Carta di Burra del 1979 e il Documento di Nara del 1994, seguiti alla Carta di Venezia del 1964. All’introduzione di nuovi impulsi sociali, scaturiti dalla soggettività dell’arte, è conseguita la revisione della definizione del cultural heritage e dell’“autenticità” e un progressivo ampliamento del “patrimonio”, prima esclusivo delle sole “opere d’arte” e attualmente comprensivo di oggetti – object - anche di uso comune e di proprietà privata. La conservazione e il restauro, quindi, sono diventate anche azioni sociali: ai valori intrinseci della visione eurocentrica, fondata sulla ricezione dell’opera d’arte nella coscienza umana limitata al fenomeno estetico e storico, si sono affiancati quelli estrinseci sociali, scientifici, spirituali e in aggiunta politici ed economici. Contestualmente si è attuato il coinvolgimento di un maggior numero di soggetti nel processo decisionale di intervento, attualmente inteso dalla “teoria contemporanea del restauro” come momento di “negoziazione” tra i diversi “valori” riconosciuti agli object. Invece, per l’orientamento del living heritage la conservazione e il restauro costituiscono dei processi riservati alle comunità locali – note come core community - detentrici del patrimonio e del know-how e uniche ad aver diritto di intervenire su di esso per garantirne la “continuità” culturale. Inoltre, con gli impulsi del postmodernismo si è registrato il cambiamento delle finalità della conservazione e del restauro, non solo più volte alla trasmissione del patrimonio alle generazioni future, ma ad assicurare, con la diffusa fruizione, gestione e valorizzazione, il raggiungimento del “benessere sociale” di quelle presenti.
La contestuale entrata in scena nel campo dell’arte della visual culture ha conferito una notevole enfasi al mondo delle immagini riferite ad oggetti anche non rubricabili come “opere d’arte”, enfatizzandone l’iconografia e l’iconologia piuttosto che le qualità materiali e formali e, con l’ausilio degli strumenti digitali, ha indirizzato le modalità operative di reintegrazione delle lacune del patrimonio culturale, prescritte dalla Teoria del restauro di Cesare Brandi, sempre più verso una ricomposizione unitaria dell’immagine, testimoniando la progressiva evoluzione dello “sguardo dell’epoca”.
Mediante alcuni casi studio paradigmatici di reintegrazione delle lacune, la ricerca ha l’obiettivo di riflettere sui valori materiali e immateriali attribuiti al patrimonio e di comprendere le ragioni che attualmente animano il dibattito internazionale e che testimoniano come i tre orientamenti della conservazione e del restauro suddetti coesistono e risultano validi a seconda del contesto geografico e culturale di appartenenza. A volte approcci diversi convivono nello stesso contesto fornendo un quadro complesso, sfaccettato e in alcuni casi paradossale, tipico di un mondo interconnesso, transculturale e relativistico. Indagare le implicazioni culturali, sociali, spirituali, politiche, economiche e a volte ideologiche che si celano dietro la reintegrazione della lacuna, non soffermandosi esclusivamente sulle problematiche formali e tecniche, permette la comprensione delle derive e dei rischi manipolativi e falsificatori del patrimonio intrapresi con alcuni interventi reintegrativi. Gli esiti di queste operazioni invitano a riflettere sul futuro della disciplina del restauro e sull’identità del “restauratore”, che attualmente sta cercando di “reinventarsi”, e pongono alcuni quesiti conclusivi che necessitano di trovare risposta.
L’introduzione dell’“intersoggettività” e della “sostenibilità semantica”, princìpi fondanti della “teoria contemporanea del restauro”, e l’obiettivo promosso dall’orientamento del living heritage di rendere attive le core communiy nei processi di cura, conservazione e “gestione del cambiamento” del patrimonio sono sufficienti per una rifondazione teorica del restauro o stanno conducendo alla dissolvenza dei temi emblematici della disciplina dibattuti da secoli nel Vecchio Continente e ad una estinzione o metamorfosi del “restauratore”? È ancora valida la Teoria del restauro di Cesare Brandi o è un testo ormai storicizzato e possiamo fare a meno delle “teorie”? Nello scenario mondiale presente e futuro possiamo in alternativa immaginare una pacifica convivenza dei tre differenti orientamenti della conservazione e del restauro o qualcuno di essi soccomberà?What are the new frontiers of conservation regarding the treatment of architectural and figurative arts loss? The Ph.D. research analyzes internationally the current intervention methods to understand the theoretical principles - if they exist - underlying the choices of loss compensation based on reflections arising from the contemporary debate among advocates of three coexisting different approaches: Cesare Brandi’s Theory of Restoration, widely spread in Romance language countries; the so-called “contemporary theory of conservation” proposed by the Spanish head of the Paper Conservation Salvador Muñoz Viñas, dominant in Anglo-Saxon countries; and the proponents of the most recent approach based on living heritage, rooted in Southeast Asian and African countries and some contexts in Latin America and recently adapted to European cultural heritage by the emerging Narrative Theory in Conservation.
Since the 1980s, there has been a shift in the Eurocentric conception of conservation and restoration, marked by the drafting of eminent documents such as the Burra Charter of 1979 and the Nara Document of 1994, following the Venice Charter of 1964. This change has been driven by new social impulses, arising from the subjectivity of art, leading to a revision of the definition of cultural heritage and authenticity and a progressive broadening of the concept of heritage. Heritage, previously limited to “artworks” only, now includes objects used in daily life and privately owned ones. Conservation and restoration, therefore, have also become social actions, alongside the intrinsic values of the Eurocentric view, rooted in the reception of artwork in human consciousness limited to aesthetic and historical aspects. Extrinsic values such as social, scientific, spiritual, political, and economic considerations have been added. Simultaneously, more stakeholders have been involved in the decision-making process of intervention, currently seen by the “contemporary theory of conservation” as a moment of “negotiation” among the different “values” recognized for the objects. On the other hand, for the living heritage approach, conservation and restoration are processes reserved for local communities, known as “core communities” who hold the heritage and know-how and have the sole right to intervene to ensure its cultural “continuity”. Furthermore, with the impulses of postmodernism, there has been a shift in the purposes of conservation and restoration, no longer solely focused on transmitting heritage to future generations but also on ensuring, through widespread access, management, and enhancement, the achievement of “social well-being” for the present generations.
The simultaneous entry of visual culture into the field of art has placed considerable emphasis on images related to objects that may not be classified as “artworks”, emphasizing their iconography and iconology rather than their material and formal qualities. With the use of digital tools, this has directed the operational methods of cultural heritage loss compensation, prescribed by Cesare Brandi’s Theory of Restoration, increasingly towards a unified recomposition of the image, reflecting the progressive evolution of the “way to look”.
Through some paradigmatic case studies of loss compensation, the research aims to reflect on the material and immaterial values attributed to heritage and to understand the reasons currently animating the international debate, which demonstrates how the three aforementioned approaches to conservation and restoration coexist and remain valid depending on the geographic and cultural context to which they belong. Sometimes different approaches coexist in the same context, providing a complex, multifaceted, and in some cases paradoxical picture typical of an interconnected, transcultural, and relativistic world. Investigating the cultural, social, spiritual, political, economic, and sometimes ideological implications behind loss compensation, beyond just the formal and technical issues, allows for an understanding of the drifts and manipulative and falsifying risks to heritage undertaken with certain interventions. The outcomes of these operations invite reflection on the future of the restoration discipline and the identity of the “conservator-restorer” who is currently seeking to “reinvent” themselves, and raise some concluding questions that need answers.
Are the principles of “intersubjectivity” and “semantic sustainability”, foundational elements of the “contemporary theory of conservation”, and the goal promoted by the living heritage orientation to activate core communities in the processes of care, conservation, and “change management” of heritage sufficient for a theoretical reformation of restoration, or are they leading to the dissolution of the emblematic themes of the discipline debated for centuries in the Old Continent and to the extinction or metamorphosis of the “conservator-restorer” ? Is Cesare Brandi’s Theory of Restoration still valid, or has it become a historicized text, and can we do without “theories”? In the present and future global scenario, can we alternatively envision a peaceful coexistence of the three different orientations of conservation and restoration, or will one of them succumb
How successful business people experience envy
No full textZ magistrskim delom je avtorica želela odgovoriti na raziskovalno vprašanje, katere vidike poslovno uspešni ljudje vključujejo v svoje opisovanje dojemanja in doživljanja zavisti v svojem delovnem okolju.
Pri raziskovanju je uporabljala metodo osnovane teorije, s katero je na podlagi empiričnih podatkov, pridobljenih z intervjuji poslovno uspešnih posameznikov, prepoznala njihovo dojemanje. Avtorica je z odprtim in osnim kodiranjem oblikovala osem glavnih kategorij: posameznikovo doživljanje čustev in občutij, posameznikovo doživljanje zavisti, posameznikovo delovanje, delovno mesto, medsebojni odnosi, poslovna uspešnost, težave in medsebojna podpora, okolje in družbeni odzivi. Posamezne kategorije je avtorica nato podrobneje obrazložila s podrednimi kategorijami in jih povezala z že obstoječo literaturo.
Magistrsko delo prinaša osvetlitev in poglobitev razumevanja problematike dojemanja zavisti poslovno uspešnih posameznikov, ki je opazna v slovenskem prostoru. Področje zavisti pri uspešnem posamezniku je v tuji literaturi dobro raziskano, na slovenskem področju pa tovrstnih raziskav izjemno primanjkuje. Rezultati raziskovalnega dela prinašajo informacije, ki so lahko v pomoč vsem, ki prihajajo v stik z zavistjo, še posebej pa ljudem, ki na kakršnem koli področju dosegajo uspehe. Najsi bo to na poslovnem ali zasebnem področju življenja.With her master\u27s thesis, the author wanted to answer the research question, which aspects of business successful people include in their description of the perception and experience of envy in their work environment.
In her research, she used the method of grounded theory, with which she identified their perception on the basis of empirical data obtained through interviews of business-successful individuals. Through open and axial coding, the author formed eight main categories: an individual\u27s experience of emotions and feelings, an individual\u27s experience of envy, an individual\u27s performance, a job, interpersonal relationships, business performance, problems and mutual support, environment and social responses. The author then explained the individual categories in more detail with subordinate categories and connected them with the existing literature.
The master\u27s thesis sheds light on and deepens the understanding of the problem of the perception of envy of business-successful individuals, which is noticeable in Slovenia. The field of envy of a successful individual is well researched in foreign literature, but in the Slovenian field such research is extremely lacking. The results of the research work provide information that can help everyone who comes into contact with envy, and especially people who are successful in any field. Be it in business or private life
James B. Conant. L’ambasciatore americano della scienza
No full textI problemi con cui Conant si misurò - il rapporto tra scienza, cultura e società, così come il rapporto tra le istituzioni di ricerca e il mondo economico e sociale - sono più che mai attuali
Trial of a desktop virtual reality application as a method of exposure for test anxiety: a qualitative study
No full textTest anxiety involves feelings of discomfort, fear and worry, impacting students’ wellbeing and academic performance. Virtual reality exposure (VRE) shows promise in mitigating test anxiety, but existing applications concern only written exams. Few VRE applications simulate one-on-one interviews with examiners, and applications for public speaking focus on formal presentations before an audience. This paper concerns a trial of a VRE application that deals with oral exams, presenting a qualitative study of a sample of undergraduate students who autonomously used the VRE application in their homes over three weeks. The application exposes students to scenarios in which a virtual examiner displays friendly, partially friendly, or unfriendly behaviour while asking questions selected from a pool defined by the student. Participants were interviewed to investigate their perceptions of and experience with the application. Thematic analysis of participants’ interviews indicates that they perceived the VRE application as valuable not only for studying and practicing oral exams but also for handling emotional aspects associated with the exam. Moreover, the application helped to increase confidence and awareness of preparation level among some participants. Finally, the paper describes participants’ suggestions emerged from the study that can be used to inform the design of this type of applications
Projection Pursuit Based on Gaussian Mixtures and Evolutionary Algorithms
No full textWe propose a projection pursuit (PP) algorithm based on Gaussian mixture models (GMMs). The negentropy obtained from a multivariate density estimated by GMMs is adopted as the PP index to be maximized. For a fixed dimension of the projection subspace, the GMM-based density estimation is projected onto that subspace, where an approximation of the negentropy for Gaussian mixtures is computed. Then, genetic algorithms are used to find the optimal, orthogonal projection basis by maximizing the former approximation. We show that this semiparametric approach to PP is flexible and allows highly informative structures to be detected, by projecting multivariate datasets onto a subspace, where the data can be feasibly visualized. The performance of the proposed approach is shown on both artificial and real datasets. Supplementary materials for this article are available online
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