1,721,117 research outputs found
LA MICROSCOPIA ELETTRONICA (SEM, CLSM) PER L’ANALISI DI MICROSISTEMI BIOLOGICI CHE COLONIZZANO I BENI CULTURALI
No full textRIASSUNTO - Il degrado dei materiali con cui sono realizzate le opere d’arte, è spesso causato dall’attività di macro e micro organismi (piante, insetti, licheni, alghe, batteri, attinomiceti etc.), denominati biodeteriogeni. Presenti in tutti gli habitat terrestri, costituiscono un serio problema per la conservazione sia in siti outdoor sia confinati, come biblioteche, archivi, istituti mussali, depositi e, comunque, in tutti quei luoghi dove si attua la conservazione/fruizione dei manufatti. In genere, non vi è luogo di conservazione che non mostri tracce di parziali o estese infestazioni/colonizzazioni che comportano alterazioni più o meno consistenti dei manufatti presenti. Le alterazioni di origine biologica si manifestano con fenomenologie abbastanza diverse in relazione agli organismi, ai parametri ambientali, alle caratteristiche dei materiali costitutivi del manufatto. I biodeteriogeni possono causare danni di tipo chimico (correlato all’effetto dei prodotti metabolici), fisico (legato alla penetrazione di cellule microbiche o di parti strutturali) ed estetico (patine, biofilm).
Pertanto, è di fondamentale importanza stabilire la presenza di macro-microrganismi e conseguentemente caratterizzarli, al fine di intervenire in modo tempestivo ed efficace limitando i danni, prima che diventino irreversibili. In tale ambito, la microscopia elettronica, sia a scansione (SEM) che a scansione laser confocale (CLSM), rappresenta uno strumento di indagine scientifica di estremo interesse.
ABSTRACT - Works of art are made of such materials that are often subjected to deterioration by macro and micro organisms (plants, insects, lichens, algae, bacteria, actinomycetes, etc..) called biodeteriogens. They are present in all terrestrial habitats, they therefore represent a serious threat for conservation of cultural assets, in both outdoor and indoor sites, such as libraries, archives, museum institutions, deposits) and all the places where the conservation/use of artifacts is implemented. Generally, all conservation/fruition sites show signs of either partial or extensive infestation/colonization, involving the hosted artifacts. Biological systems, strongly related to environmental parameters and characteristics of the constitutive materials, are able to induce a range of sufficiently wide alterations. The biodeteriogens can cause chemical (related to the effect of metabolic products), physical (related to penetration of microbial cells or structural elements) and aesthetic (coatings, biofilms) damages.
Therefore, it is essential to establish the presence of macro and microorganisms and to identify them, in order to promptly and effectively intervene to restrain the damage, before it becomes irreversible. In this context, electron microscopy, both scanning (SEM) and confocal laser scanning (CLSM) represent scientific tools of great interest in the diagnostic field
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
Supramaximal exercise mobilizes haematopoietic progenitors and reticulocytes in athletes
No full textAm J Physiol Regul Integr Comp Physiol. 2005 Nov;289(5):R1496-503. Epub 2005 Jul 14.
Supramaximal exercise mobilizes hematopoietic progenitors and reticulocytes in athletes.
Morici G, Zangla D, Santoro A, Pelosi E, Petrucci E, Gioia M, Bonanno A, Profita M, Bellia V, Testa U, Bonsignore MR.
SourceDepartment of Experimental Medicine, University of Palermo, Italy.
Abstract
Marathon runners show increased circulating CD34+ cell counts and postexercise release of interleukin-6 (IL-6), granulocyte-colony stimulating factor (G-CSF) and flt3-ligand (Bonsignore MR, Morici G, Santoro A, Pegano M, Cascio L, Bonnano A, Abate P, Mirabella F, Profita M, Insalaco G, Gioia M, Vignola AM, Majolino I, Testa U, and Hogg JC. J Appl Physiol 93: 1691-1697, 2002). In the present study we hypothesized that supramaximal ("all-out") exercise may acutely affect circulating progenitors and reticulocytes and investigated possible mechanisms involved. Progenitor release was measured by flow cytometry (n = 20) and clonogenic assays (n = 6) in 20 young competitive rowers (13 M, 7 F, age +/- SD: 17.1 +/- 2.1 yr, peak O2 consumption: 56.5 +/- 11.4 ml.min(-1).kg(-1)) at rest and shortly after 1,000 m "all-out." Release of reticulocytes, cortisol, muscle enzymes, neutrophil elastase, and several cytokines/growth factors was measured. Supramaximal exercise doubled circulating CD34+ cells (rest: 7.6 +/- 3.0, all-out: 16.3 +/- 9.1 cells/mul, P < 0.001), and increased immature reticulocyte fractions; AC133+ cells doubled, suggesting release of angiogenetic precursors. Erythrocyte burst forming units and colony forming units for granulocytes-monocytes and all blood series increased postexercise by 3.4-, 5.5-, and 4.8-fold, respectively (P < 0.01 for all). All-out rowing acutely increased plasma cortisol, neutrophil elastase, flt3-ligand, hepatocyte growth factor, VEGF, and transforming growth factor-beta1, and decreased erythropoietin; K-ligand, stromal-derived factor-1, IL-6, and G-CSF were unchanged. Therefore, all-out exercise is a physiological stimulus for progenitor release in athletes. Release of reticulocytes and proangiogenetic cells and mediators suggests tissue hypoxia as possibly involved in progenitor mobilization.
PMID:16020520[PubMed - indexed for MEDLINE
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Respiratory Effects of Exposure to Traffic-Related Air Pollutants During Exercise
Full text linkTraffic-related air pollution (TRAP) is increasing worldwide. Habitual physical activity is known to prevent cardiorespiratory diseases and mortality, but whether exposure to TRAP during exercise affects respiratory health is still uncertain. Exercise causes inflammatory changes in the airways, and its interaction with the effects of TRAP or ozone might be detrimental, for both athletes exercising outdoor and urban active commuters. In this Mini-Review, we summarize the literature on the effects of exposure to TRAP and/or ozone during exercise on lung function, respiratory symptoms, performance, and biomarkers. Ozone negatively affected pulmonary function after exercise, especially after combined exposure to ozone and diesel exhaust (DE). Spirometric changes after exercise during exposure to particulate matter and ultrafine particles suggest a decrease in lung function, especially in patients with chronic obstructive pulmonary disease. Ozone frequently caused respiratory symptoms during exercise. Women showed decreased exercise performance and higher symptom prevalence than men during TRAP exposure. However, performance was analyzed in few studies. To date, research has not identified reliable biomarkers of TRAP-related lung damage useful for monitoring athletes' health, except in scarce studies on airway cells obtained by induced sputum or bronchoalveolar lavage. In conclusion, despite partly counteracted by the positive effects of habitual exercise, the negative effects of TRAP exposure to pollutants during exercise are hard to assess: outdoor exercise is a complex model, for multiple and variable exposures to air pollutants and pollutant concentrations. Further studies are needed to identify pollutant and/or time thresholds for performing safe outdoor exercise in cities
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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