In this work we investigate various aspects of the finishing process in ancient bronze sculptures by means of active infrared thermography (IRT). Active IRT provides information on surface and sub-surface features of the investigated artefact, by analysing the heat diffusion process induced within the sample by appropriate thermal stimulations usually produced by absorption of light emitted by different sources. The aim of this research is, in particular, to investigate the processing of bronze surfaces, revealing repairs like plugs, fillings, local castings and concealed marks. 相似文献
This paper claims that knowledge-relatedness is a key factor in affecting firms’ technological diversification. The hypothesis is tested that firms extend the range of their innovative activities in a non-random way. Specifically, we test the extent to which firms diversify their innovative activities across related technological fields, i.e. fields that share a common knowledge base and rely upon common heuristics and scientific principles. The paper proposes an original measure of knowledge-relatedness, using co-classification codes contained in patent documents, and examines the patterns of technological diversification of the whole population of firms from the United States, Italy, France, UK, Germany, and Japan patenting to the European Patent Office from 1982 to 1993. Robust evidence is found that knowledge-relatedness is a major feature of firms’ innovative activities. 相似文献
In the paper some case studies of damaged towers in Italy are presented: the Tower Masserano of Palace Ferrero - La Marmora at Biella, the bell tower of the Collegiata of San Vittore at Arcisate, and three medieval towers in Alba. A methodology is put forward for combining laboratory and nondestructive testing methods with monitoring systems in order to reach the goal of evaluating the state of conservation of historic towers and its evolution in time. 相似文献
Maintaining the microclimatic parameters at the desired value is essential for artefacts preservation. In order to control the status of the microclimatic parameters, a continuous monitoring of the indoor environmental provides conservators, curators, restorers, and lenders with an exact knowledge of the microclimatic conditions under which the works of art are kept. Moreover, the monitoring results give important information in order to make adequate changes to the control strategy of microclimatic parameters. From this point of view, monitoring is an essential tool to develop an actual preventive control programme aimed at maintaining the optimal microclimatic conditions for preservation. As a consequence, long-term monitoring has to be applied to prevent deterioration of works of art. The widespread opinion that a correct approach to the topic of microclimate control for artefacts preservation is not only and necessarily to provide buildings with sophisticated environmental control systems, but mainly to investigate the actual environmental dynamics and, before any structural intervention, to define the compatibility between the climate control potentials and the preservation requirements, has become more and more firm among the experts. Monitoring also allows to verify the capacity of the “building and Heating, Ventilation and Air Conditioning (HVAC)” system to maintain the desired thermo-hygrometric values within the operating conditions. To this aim, the Italian Standard UNI 10829 (1999) defining monitoring, elaboration and analysis of the microclimatic data as supporting actions for artefacts preservation, led to the need of a long-term monitoring and of a statistical approach to the data management. The approach proposed by the Italian Standard has been recently adopted by a European Standard (EN 15251, 2007). In accordance with the Standards mentioned above, in this paper an operational procedure to assess the thermo-hygrometric quality in museums is firstly synthetically presented and than applied to a case study. In particular, the procedure is developed in order to define the thermo-hygrometric quality level of the exhibition areas in the large museum complex of “Santa Maria della Scala” in Siena (Italy) during the international temporary exhibition “Duccio. La nascita della pittura senese” (“Duccio. The birth of Sienese Painting”). 相似文献
Adobe is a construction technique that uses raw clayey earth mixed and moulded to form blocks to realize a bearing wall. Romans were also used to add sand or coarse sand into the mixture to “degrease” clay and to allow to make it into a mixture. Fibres such as straw were often added into the mixture. Anyway, ancient home brick-makers have not had a chance to do scientific experimental investigation on the balance of ingredients and the optimisation of this production. This paper elaborates on how workability and mechanical properties of Roman ancient adobe earthen bricks change by varying the percentage of an on situ soil, straw and coarse sand into the mixture to produce them. The comparisons were also made with the only-earth samples. Breaking manners of all the samples were also compared. 相似文献
Based on the premise that classroom interactions unfold through a complex series of circular influences between teacher and students, the aim of this longitudinal study was to test a reciprocal effects model connecting students’ perceptions of interpersonal justice, on the one hand, and student engagement, agency and anger, on the other. Self-report measures of interpersonal justice, student engagement, agency and anger were collected from 454 Year Nine students from Northern Italy in a 3-wave longitudinal research design. Structural equation modelling with latent variables indicated that interpersonal justice in wave 1 had a negative effect on both student agency and anger in wave 2, while interpersonal justice in wave 2 only negatively predicted student anger in wave 3. With respect to the reciprocal effects, student engagement in wave 2 was found to positively predict interpersonal justice in wave 3, while a negative effect close to statistical significance was observed from student agency in wave 2 to interpersonal justice in wave 3. These results are discussed in terms of their implications for teacher practice, as they emphasize that (a) the two main facets of student participation, namely engagement and agency, are differently interconnected with the learning environment, and (b) the perception of being treated fairly is important to the point that its deficiency triggers a persistent feeling of anger in students.
The confined flow of red blood cells (RBCs) in microvasculature is essential for oxygen delivery to body tissues and has been extensively investigated in the literature, both in vivo and in vitro. One of the main problems still open in microcirculation is that flow resistance in microcapillaries in vivo is higher than that in vitro. This discrepancy has been attributed to the glycocalyx, a macromolecular layer lining the inner walls of vessels in vivo, but no direct experimental evidence of this hypothesis has been provided so far. Here, we investigate the flow behavior of RBCs in glass microcapillaries coated with a polymer brush (referred to as “hairy” microcapillaries as opposed to “bare” ones with no coating), an experimental model system of the glycocalyx. By high-speed microscopy imaging and image analysis, a velocity reduction of RBCs flowing in hairy microcapillaries as compared to bare ones is indeed found at the same pressure drop. Interestingly, such slowing down is larger than expected from lumen reduction due to the polymer brush and displays an on-off trend with a threshold around 70 nm of polymer brush dry thickness. Above this threshold, the presence of the polymer brush is associated with an increased RBC deformation, and RBC velocity is independent on polymer brush thickness (at the same pressure drop). In conclusion, this work provides direct support to the hypothesis that the glycocalyx is the main factor responsible of the higher flow resistance found in microcapillaries in vivo. 相似文献
This study analyses the university choices of male and female students in Italy over the 2003–2012 period and for two sub-periods before (2003–2008) and after (2009–2012) the 2008 financial crisis. The analysis is guided by human capital, signalling and preference theories and implemented through a competing destinations model that controls for the socio-economic features of both the region of origin and destination. The findings show that in the post-crisis period, males became more career-oriented in their university choices due to increasingly constrained and competitive labour markets. The constrained post-crisis labour markets led females to focus more on the educational experience than on future employability prospects. Our results suggest that the financial crisis maintained or even widened gendered social roles as they relate to university choices; specifically, males assumed an even greater career-centred family role, whereas females adopted more adaptive lifestyles that potentially place them at a disadvantage in the labour market and in society in years to come. 相似文献
Reflexivity is a learning process that, through questioning and critically monitoring objectives and methods in use, promotes a change of habits and routines and, in so doing, fosters organizational performance and innovativeness. This paper looks at the contribution of team reflexivity to enhancing openness to innovation, and the mediating role of individual and team involvement. Specifically we tested whether affective commitment (Study 1, n=156) and a team climate of support for innovation (Study 2, n=152) facilitate reflexivity processes in promoting organizational openness to innovation. Overall, results confirmed that reflexivity enhances innovativeness, and this relationship is mediated by a high degree of involvement that increases the motivation of teammates and their engagement in innovation processes. 相似文献