1,722,002 research outputs found
Premessa
No full textpremessa al volume "Il postfotografico". Descrizione degli obiettivi del volume e delle sezioni in cui è suddiviso
Development of a novel approach to overcome biofilm formation by natural product derivatives
No full textWith the aim to prevent biofilm formation, and based on our previous studies, 1, 2 we explored new strategies
involving inorganic nanoparticles for surface covering. In detail, we investigated the functionalization of silica
nanoparticles with natural derivatives showing anti-biofilm properties, using linkers of different nature and
length. After their analytical characterization, the new derivatives were used to obtain glass coverslips by spin-coating technology for the biological testing (Figure 1). The promising results towards E. coli and P.
aeruginosa will be presented.
1 C. Cattò; S. Dell'Orto; F. Villa; S. Villa; A. Gelain; A. Vitali; V. Marzano; S. Baroni S; F. Forlani; F. Cappitelli. PLoS ONE 2015, 10(7), e0131519.
2 C. Cattò; G. Grazioso; S. Dell’Orto; A. Gelain; S. Villa, V. Marzano; A. Vitali; F. Villa; F. Cappitelli; F. Forlani. Biofouling 2017, 33, 235-25
Subaerial biofilms: new horizons in stone biodeterioration research
No full textScience and technology interact with art and culture in many ways: the arts draw both inspiration and new materials from science, while the scientific examination of art and artifacts has provided us with important insights into the progress of human civilizations. Now, science - in particular biological science - has an even more important role: to protect and conserve mankind's often fragile, cultural heritage for future generations.
The evidence that many of the world’s most precious artworks are made of stone and have a finite life drives the interest in this topic. Their irreversible deterioration due to biological attack is a worldwide concern. Microorganisms colonize outdoor lithic surfaces and develop into biofilms at the interface solid/air (subaerial biofilms, SABs), which, in turn might cause aesthetic, chemical and physical decay. Although it has been estimated that at least 99% of the world's microbial biomass exists in biofilms, the role and behavior of microorganisms within the biofilm matrix and their complex interactions with the environment is still unknown.
In this talk I will approach the complex interaction between SABs and cultural heritage assets from two different angles: 1) the establishment of a laboratory model system of SABs relevant to cultural heritage studies, and 2) the urgent need to develop preventive antibiofilm strategies.
1) One of the main gaps challenging our understanding of the physiology and the activity of biofilms inhabiting outdoor stone heritage is the lack of a model system of SABs. To overcome this limitation, we developed a methodology to obtain a laboratory model of a dual-species SAB that is relevant to cultural heritage studies. The results underscore the ability of the dual-species SAB model to underpin functional traits characteristic of biofilms inhabiting lithic substrate such as: i) microcolonies of aggregated bacteria; ii) network-like structure following surface topography; iii) deconstruction of the complexity of environmental samples into their main component parts (e.g. phototroph-heterotroph interactions); iv) ability to change the chemical parameters that characterize the microhabitats; v) survival in harsh environments and vi) biocide tolerance. To the best of our knowledge, this is the first time that a phototroph-heterotroph association at the stone/air interface has been successfully obtained at laboratory scale starting from two introduced, controlled species and not from an environmental microbial consortium. The current study has the potential to significantly advance our mechanistic understanding of the biofilm-stone-air interplay that has proven difficult to study in field experiments due to the inaccessibility of samples and the complexity of the ecosystem under investigation.
2) SABs inhabiting artistic surfaces, as any other biofilms, show a remarkable resistance to biocides, making them recalcitrant to traditional cleaning procedures. Plants offer a virtually inexhaustible and sustainable resource of very interesting classes of biologically active, low-molecular-weight compounds (parvome). In the past, the plant parvomes were screened mainly for their lethal effects, disregarding concentrations and ecologically relevant functions of these molecules in the natural context. Testing sub-lethal concentrations of plant-derived compounds mimicking environmental levels may be critical to revealing mechanisms subtler than the killing activity, e.g. those influencing the multicellular behavior, offering an elegant way to develop novel biocide-free antibiofilm strategies. In a cross-disciplinary fashion, I will illustrate recent successes of sub-lethal concentrations of the plant-derived compound zosteric acid, its mechanism of action, and the structural characteristics responsible for the anti-biofilm activity, envisioning applications on cultural heritage assets
Knowledge behind the scenes of a peer-reviewed journal helps in publishing your manuscript
Full text linkThis paper provides insights into the paper submission and review processes and the possible reasons behind
paper acceptance or rejection. The main target of this paper is emerging researchers who are writing their first
scientific papers in peer-reviewed journals. This manuscript gives clues on how to select a journal and what a
preprint is, introduces authorship and the roles of editors, reviewers, and publishers, sheds light on the editorial
process, and briefly introduces some ethical issues arising in scholarly publishing. The content is based on a course
offered annually to doctoral students at the University of Milan and keeps into account frequently asked questions.
The authors of this paper are an editor-in-chief and an associated editor of scientific journals, respectively
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Il postfotografico. Dal Selfie alla fotogrammetria digitale
No full textLa fotografia della seconda, o terza, rivoluzione digitale è un magma che si espande in modo incontrollabile. Ancora non abbiamo chiaro che cosa significhi usare il cellulare come macchina fotografica, confezionare le immagini per i social, produrre una massa di scatti che si riversano ogni giorno in Internet divenendo parte di giganteschi database, che già algoritmi e intelligenza artificiale hanno cambiato il codice genetico dell’atto fotografico. Come affrontare la rivoluzione in atto? Quali strumenti servono per analizzare il fenomeno in corso, e in che misura la teoria della fotografia può ancora soccorrerci? Il postfotografico – come concetto inclusivo che fa da ponte tra tutte le fasi della fotografia digitale – richiede una messa a fuoco a piú livelli. Come diversa tecnica della luce, diverso gesto, diversa politica e scienza del visibile. Una differenza che non
è novità assoluta ma piuttosto il riaffiorare di un’idea originaria di fotografia, lasciata ai margini per gran parte del Novecento. I quindici saggi qui contenuti ne approfondiscono ciascuno un aspetto, tra passato e futuro: la fotografia come metodo di tracciamento, raccolta di luce non visibile, tecnica di misurazione del Sé e del mondo, nodo di connessioni, oggetto paradossale che non è piú obbligatoriamente visto, ma nondimeno è presente, e ancora capace di permettere una partecipazione allargata al mondo
Plant-derived bioactive compounds at sub-lethal concentrations: towards smart biocide-free antibiofilm strategies
Full text linkBiofilm resistance to biocides is becoming a global issue with an impact on many fields, including health care, agriculture, the environment, society and industry. Plants offer a virtually inexhaustible and sustainable resource of very interesting classes of biologically active, low-molecular-weight compounds (parvome). In the past, the plant parvomes were screened mainly for their lethal effects, disregarding concentrations and ecologically relevant functions of these molecules in the natural context. Testing sub-lethal concentrations of plant-derived compounds mimicking environmental levels may be critical to reveal mechanisms subtler than the killing activity, e.g. those influencing the multicellular behavior, offering an elegant way to develop novel biocide-free antibiofilm strategies. In a cross-disciplinary fashion, we illustrated recent successes of sub-lethal concentrations of plant-derived compounds, their ecological insight, pro et contra, future directions and impacts, envisioning implications for policy making and resource management
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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