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31.
Luigi Gabrielli Marta Sitges Mario Chiong Jorge Jalil María Ocaranza Silvana Llevaneras 《European Journal of Sport Science》2018,18(9):1288-1297
Moderate endurance exercise has long been considered an essential element to maintain cardiovascular health, and sedentary behaviour in the general population has been related to a significant increase in all-causes of mortality, cardiovascular disease mortality and cardiovascular disease incidence. However, a growing group of people performs an intense exercise that leads to multiple heart adaptive changes that are collectively called “athlete’s heart”. In this review, we discussed the evidence of cardiac remodelling process secondary to repetitive and strenuous exercise in some predisposed athletes that produces intense and probably deleterious changes in cardiac morphology and function with no clear clinical significance in long-term follow-up. Moreover, we also discussed the individual biological response to exercise assessed by myocardial damage, inflammation, oxidative stress, fibrosis and ventricular hypertrophy biomarkers showing different intensities with equivalent exertion. 相似文献
32.
Karen Guldberg Alexia Achtypi Luigi D’Alonzo Katerina Laskaridou Damian Milton Paola Molteni 《International Journal of Research & Method in Education》2021,44(1):96-111
ABSTRACT Although theories around Communities of Practice have gained significant ground in recent years and have become an important focus for organizational development, there is a gap in studies that investigate what members gain from participation in these communities. This paper explains how the value creation framework was implemented in a transnational research and development project in autism education by examining cycles of value creation and drawing on two types of data identified by Wenger and colleagues. The value creation framework is a theoretically driven framework to assess social learning in communities. Participants involved in the learning space were co-researchers engaged in a process of investigating, sharing and reflecting on their practice. The paper discusses the methodological challenges and strengths of using the value creation framework, with a particular focus on how insights and interactions led to subsequent changes in the practice of the participants. This work has the potential to make an important contribution to methods and analysis in assessing social learning and pathways to impact in participatory research and development projects more broadly. 相似文献
33.
Giacomo Cipriani Antonella Salvini Luigi Dei Azzurra Macherelli Francesco Saverio Cecchi Carlo Giannelli 《Journal of Cultural Heritage》2009,10(3):388-395
The cross-linking processes of three drying oils (poppy, linseed, walnut), a class of organic compounds very important in the field of artworks, were studied by means of 1H-NMR spectroscopy, following the change of the protons signals when oils are heated at 60 °C in the presence of air or nitrogen gas. This preliminary information is particularly important to identify the presence of drying oils within a solid painting film. We demonstrated that it was possible to study these films by swollen-state NMR, an innovative spectroscopy method that can directly analyze very small semisolid samples instead of solutions. The main advantages of this method are the short time of analysis, the possibility to analyze samples without any preliminary treatment, and the small quantity of the sample required. Therefore, swollen-state NMR technique was used to characterize three real painting films: in this way, we succeeded in recognizing in real paintings specimens the presence of drying oils employed as binders, avoiding any interferences due to other organic compounds acting as binding agents, like waxes or egg-yolk media. 相似文献
34.
Emiliano Carretti Marco Milano Luigi Dei Piero Baglioni 《Journal of Cultural Heritage》2009,10(4):501-508
The present work was one of the first attempts to analyze the conservation status of two ferrotypes, ancient photographic plates realized on a support made of iron. The photographic material was constituted of collodion as binder for the photosensitive silver halides grains. The two ferrotypes studied belonged to a private collection of a family from Durham, UK, and were made at the end of the 19th century. The analytical techniques used for the morphological and physicochemical characterization were noninvasive. The surface morphology was studied by means of optical microscopy (OM) and environmental scanning electron microscopy (ESEM) coupled with an energy dispersive X-rays (EDX) system for the elemental analysis. These techniques, together with microreflectance Fourier transform infrared spectroscopy (μ-FTIR) and contact angle, allowed to obtain information on both the chemical – elemental – composition of the materials constituting the ferrotypes, and the conservation status of these photographic plates. The study showed that the physicochemical diagnostics allowed to characterize the two ferrotypes that, despite their similar age and provenance, showed different conservation status, surface properties, and elemental composition. 相似文献
35.
Maria Chiara Gallotta Gian Pietro Emerenziani Sara Iazzoni Luigi Iasevoli Laura Guidetti 《Journal of sports sciences》2017,35(15):1547-1555
Aim of this study was to evaluate the effectiveness of two different 5-month physical education (PE) interventions conducted by a specialist PE teacher on primary school children’s skill- and health-related outcomes. About 230 children were randomly assigned to one of three intervention groups: experimental_1 group, experimental_2 group or control group (school curriculum given by the generalist teacher). Pre- and post-intervention tests assessed pupils’ fitness (pacer, curl-up, push-up, trunk lift, sit and reach tests) and gross motor coordination (shifting platforms, balance beam, jumping laterally, hopping on one leg over an obstacle tests). Both experimental groups significantly improved some fitness and coordinative tests after the intervention period when compared with control group. However, no differential changes on coordinative development were observed between the 2 experimental groups. Results of this study demonstrated that children benefitted from a well-structured PE intervention conducted and supervised by a specialist PE teacher improving their motor skills and fitness. 相似文献
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37.
In this study the authors propose a distinction between two approaches to market information, rooted in the marked-based learning theory. The two approaches are conceptualized and operationalized on the basis of their differences along three processes: generation, dissemination and use of market information. In the retrospective approach, the generation process is based on expressed customer needs and extant market relations; the dissemination is based on formal mechanisms; the use process is more instrumental. In the forward-looking approach, the generation process is based on latent customer needs and on the evolutionary patterns of the future market relations; the dissemination process is more informal; the use of information is more conceptual. A series of hypotheses concerning the relationships between these approaches, product innovativeness and firm performance are tested on a sample of Italian fashion firms. Results suggest that the two approaches are complementary for firm performance, but have opposite effects on product innovativeness: while a forward-looking approach is positively related to product innovativeness, a retrospective approach seems to be negatively related. The results also shed light on how market information approaches and product innovativeness jointly affect firm performance. 相似文献
38.
Emiliano Carretti Irene Natali Caterina Matarrese Paola Bracco Richard G. Weiss Piero Baglioni Antonella Salvini Luigi Dei 《Journal of Cultural Heritage》2010,11(4):1555-380
The procedures for making and applying a new family of high viscosity aqueous polymeric dispersions based on poly(vinyl alcohol)-borax (PVA-borax) matrices are presented. A specific system of this type has been used to remove an oxidized varnish coating from the surface of “Coronation of the Virgin with Saints”, a 15th century egg tempera painting on wood by Neri di Bicci (Florence, 1418–1492). FTIR spectra showed that the oxidized varnish was constituted of highly aged shellac resin. Good cleaning performance was attained when the liquid portion of the dispersion consisted of a mixture of water and acetone. Rheological investigations indicate that the acetone content does not affect the mechanical properties of the polymeric dispersion. Those mechanical properties permit easy removal of the cleaning agent simply by peeling it from the surface by means of a forceps or spatula once it has carried out its cleaning function. Optical microscopic and FTIR investigations show that the cleaning agent is able to remove the oxidized varnish coating from the surface of the Neri di Bicci painting without leaving detectable residues. 相似文献
39.
Crisafulli A Melis F Tocco F Pittau G Lorrai L Gori T Mancardi D Concu A Pagliaro P 《Journal of sports sciences》2007,25(12):1393-1401
Nitroglycerin induces the so-called second window of protection (SWOP), which alleviates myocardial damage and stunning after ischaemia/reperfusion. To determine whether myocardial performance during exercise is improved in the second window of protection, we studied the haemodynamic responses of 12 trained and 11 sedentary individuals during a sequence of maximal tests on a cycle ergometer. A baseline test (basal test) was followed by a second effort performed during the second window of protection (exercise-SWOP test). Haemodynamics was also evaluated after pharmacologically induced SWOP 48 h after transdermal administration of 10 mg of nitroglycerin (pharmacologically induced SWOP test). The exercise-SWOP and pharmacologically induced SWOP tests were separated by a 1-week washout period. Endothelial-dependent vasodilatation after nitroglycerin pre-treatment was also assessed in five sedentary individuals to determine whether nitrate donors could affect vascular function. We found that nitroglycerin pre-treatment did not induce any improvement in haemodynamics in either trained or sedentary individuals, since maximum values of workload, heart rate, stroke volume, cardiac output, myocardial contractility, and double product were similar between the exercise-SWOP and pharmacologically induced SWOP tests in both groups. Furthermore, nitroglycerin pre-treatment did not alter flow-mediated dilation during pharmacologically induced SWOP. Although nitroglycerin pre-treatment alleviates post-ischaemic myocardial stunning, our results suggest that it does not affect the myocardial performance of healthy individuals during exercise performed in the second window of protection, independently of the training status of the individuals. Moreover, nitroglycerin pre-treatment does not ameliorate endothelial function. 相似文献
40.
Emiliano Carretti Luigi Dei Richard G. Weiss Piero Baglioni 《Journal of Cultural Heritage》2008,9(4):386-393
The application of a new class of organogels as cleaning tools for painted surfaces is described. It combines some of the most attractive features of cleaning liquids and normal gels while diminishing the deleterious characteristics of both. Thus, the ‘latent’ gellant, polyethyleneimine (PEI), reacts with CO2 at room temperature in solutions of several organic liquids to produce an ammonium carbamate form (PEICO2). This charged species organizes itself into 3D polymer networks which immobilize the liquids as gels. The properties of the original solution (i.e. a free-flowing liquid) are re-established immediately after addition of a small amount of a weak acid which displaces the CO2 molecules and makes the PEI chains positively charged. The visual changes are substantiated by rheological analyses. Results from analytical tests to determine the utility of these gels as cleaning tools for painted surfaces of historical and artistic interest, have been obtained from contact angle and FTIR measurements as well as visual comparisons of the surfaces before and after application of the gels. The analyses indicate that the PEICO2-based organogels were very effective in removing different surface patinas from painted supports. A surface layer of dammar was completely removed from a test canvas with oil paint, an aged painting from the XIX century, and a XV century oil-on-wood panel attributed to Mariotto di Cristoforo. Finally, a surface acrylic polymeric resin (used in a restoration performed during the 1960s) was also successfully removed from Renaissance wall paintings decorating the Santa Maria della Scala Sacristy in Siena, Italy. The isothermally rheoreversible gel approach described in this work represents a new, highly versatile, and very efficient method for removing aged surface patinas from works of art. 相似文献