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Enrico Quagliarini Federica Bondioli Giovanni B. Goffredo Antonio Licciulli Placido Munafò 《Journal of Cultural Heritage》2012,13(2):204-209
The development and application of self-cleaning treatments on historical and architectural stone surfaces could be a significant improvement in conservation, protection and maintenance of Cultural Heritage. In this paper, a TiO2-based coating has been investigated in order to evaluate its possible use as a self-cleaning treatment. This coating was obtained by a sol-gel and a hydrothermal (134 °C) processes and then it was applied on travertine (a limestone often used in historical and monumental buildings) in two ways, obtaining a single-layer and a three-layer treatment, respectively. In order to verify its potential use in the field of Cultural Heritage, the maintenance of appearance properties of the treated travertine surfaces was monitored by colour and gloss analyses. Besides, de-pollution and soiling removal tests were carried out under ultraviolet-light exposure to evaluate photo-induced effects and self-cleaning efficiency. Results seem to allow the use of TiO2-based treatments on historical and architectural surfaces made up by travertine, where de-pollution and self-cleaning photo-induced effects are well evident, maintaining their original visual appearance. Anyway, before applying TiO2-based coatings as conservative treatments, further tests are needed especially on their durability, that is mandatory for Cultural Heritage applications. On-site test in an urban environment and accelerated test by weatherometer are currently under way. 相似文献
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Luca Paolo Ardigò Johnny Padulo Andrea Zuliani Carlo Capelli 《Journal of sports sciences》2015,33(17):1853-1858
This study aimed to apply a validated bioenergetics model of sprint running to recordings obtained from commercial basic high-sensitivity global positioning system receivers to estimate energy expenditure and physical activity variables during soccer refereeing. We studied five Italian fifth division referees during 20 official matches while carrying the receivers. By applying the model to the recorded speed and acceleration data, we calculated energy consumption during activity, mass-normalised total energy consumption, total distance, metabolically equivalent distance and their ratio over the entire match and the two halves. Main results were as follows: (match) energy consumption = 4729 ± 608 kJ, mass normalised total energy consumption = 74 ± 8 kJ · kg?1, total distance = 13,112 ± 1225 m, metabolically equivalent distance = 13,788 ± 1151 m and metabolically equivalent/total distance = 1.05 ± 0.05. By using a very low-cost device, it is possible to estimate the energy expenditure of soccer refereeing. The provided predicting mass-normalised total energy consumption versus total distance equation can supply information about soccer refereeing energy demand. 相似文献
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We present a microfluidic device capable of separating platelets from other blood cells in continuous flow using dielectrophoresis field-flow-fractionation. The use of hydrodynamic focusing in combination with the application of a dielectrophoretic force allows the separation of platelets from red blood cells due to their size difference. The theoretical cell trajectory has been calculated by numerical simulations of the electrical field and flow speed, and is in agreement with the experimental results. The proposed device uses the so-called "liquid electrodes" design and can be used with low applied voltages, as low as 10 V(pp). The obtained separation is very efficient, the device being able to achieve a very high purity of platelets of 98.8% with less than 2% cell loss. Its low-voltage operation makes it particularly suitable for point-of-care applications. It could further be used for the separation of other cell types based on their size difference, as well as in combination with other sorting techniques to separate multiple cell populations from each other. 相似文献
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This paper addresses the marketing approaches adopted by Knowledge-Intensive Business Services (KIBS) companies, whose main production factor and outcome is knowledge. Given the key role that client-provider cognitive interactions play in the provision of such services, the study adopts the conceptual framework of Service-Dominant (S-D) logic, that the recent literature considers being fully in line with the core characteristics of KIBS companies. Starting from the assumption that service is the fundamental basis of any economic exchange, this logic suggests a shift from the traditional ‘market to’ approach, which has been developed for tangible goods, to a ‘market with’ approach, where customers and providers collaborate along the whole marketing process. The research was carried out by means of a multiple case study of 20 small computer services companies in Italy, and aimed to understand if (and to what extent) the marketing initiatives of such companies are consistent with the S-D logic, and to discuss the major challenges that they have to face in order to follow the new logic. 相似文献
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Laura Chimenti Giuseppe Morici Alessandra Paternò Anna Bonanno Marcello Vultaggio Vincenzo Bellia 《Journal of sports sciences》2013,31(9):925-935
Abstract Runners have increased numbers of neutrophils in the airways at rest and after exercise compared with sedentary individuals. The aim of this study was to determine whether Mediterranean seasonal changes in temperature, humidity or airborne pollutants affect the airway cells of runners training outdoors in an urban environment. In nine male amateur runners, cell composition, apoptosis, and inflammatory mediators were measured in induced sputum collected at rest (baseline) and the morning after races held in the fall (21 km), winter (12 km), and summer (10 km). Concentrations of air pollutants were below the alert threshold at all times. Neutrophil differential counts tended to increase after all races (P = 0.055). Apoptosis of neutrophils increased with ozone (P < 0.005) and particulate matter <10 μm (PM10) (P < 0.05) exposure. Bronchial epithelial cell counts were low at all times and weakly correlated with ozone and PM10 concentrations. Apoptotic bronchial epithelial cells increased after all races (P < 0.05). Inflammatory mediators in induced sputum were low at baseline and after the races, and correlated with neutrophil differential counts only at rest. In conclusion, apoptosis of airway cells in runners appears to be affected by both exercise and environmental conditions. Apoptosis of neutrophils increased with exposure to environmental pollutants while apoptosis of bronchial epithelial cells increased after intense exercise. Since no relationship was observed between neutrophil counts and inflammatory mediators 20 h after races, airways inflammation at this time point appears blunted in healthy runners and little affected by exposure to mild seasonal changes and airborne pollutants. 相似文献
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Jörg Härterich Christine Kiss Martin Mönnigmann Moritz Schulze Darup Roland Span 《European Journal of Engineering Education》2012,37(3):255-266
First-year engineering students often complain about their mathematics courses as the significance of the difficult and abstract calculus to their field of study remains unclear. We report on the project MathePraxis, a feasibility study which was designed as a means to give first-year students some impression about the use of mathematics in real practice. We aim to increase the motivation and retention rates among engineering students by connecting the contents of the first-year mathematics lectures with practical applications. We developed three projects, two of which are described in this article: an inverted pendulum considered as a model for the automated control within a Segway and a study on the optimal design of a ribbed cooler. In this article, we briefly present the mathematical content of the projects and report on their implementation. 相似文献
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Federico Onali Carla M. Calò Myosotis Massidda Miguel M. Álvarez-Álvarez 《European Journal of Sport Science》2018,18(10):1376-1382
A common missense mutation (1470T > A) in gene SLC16A1 responsible for an amino acid substitution in protein MCT1 has been associated with differential lactate transport and hence, differences in physical performance and muscle injuries in relation to physical exercise. This study describes, for the first time, the worldwide variation of MCT1 variant 1470T > A at an intra- and inter-continental level. Two thousand five hundred and four individual genotypes of 26 populations clustered in 5 population groups have been analysed with data downloaded from the public database 1000 Genomes Phase 3 Browser. Several parameters of population differentiation and structure have been explored as well as selection signatures in the whole gene. Allele T, the common variant, shows extremely high values in Sub-Saharan African groups (frequencies 86–91%) as compared with the remaining world regions (69–49%). TT genotype also predominates in African groups, showing significant differences with the rest of world populations. In view of the evidence that the TT genotype is associated with clinical implications and a better predisposition to sprint/power performances, we suggest that the high presence of the TT genotype in African populations should be taken into account in future association studies at both medical and sports fields. 相似文献
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This article explores the relationship between children's knowledge and perceptions about their rights and subjective well-being (SWB) in a sample of 8-, 10- and 12-year-olds in 18 countries, taking account of gender differences. Children's knowledge and perceptions about their rights were analysed considering whether they reported that they knew their rights, whether they had heard about the UN Convention on the Rights of the Child (CRC) and whether they thought that, in their country, adults respected their rights. To explore SWB, a modified version of the Student's Life Satisfaction Scale, adapted by the Children's Worlds project, was used. Children reporting that they knew their rights, knew about the CRC, or thought that in their country adults respected their rights demonstrated significantly higher SWB scores than those reporting otherwise in the 18 countries. The effects of perceiving that adults in general respected children's rights in their own country on SWB were much more important than the knowledge of children's rights or the knowledge of the CRC. Results provide useful indications on how to promote children's well-being in public policies, including in education, through the promotion of their rights. 相似文献