The Influence of Hygroscopic Materials on the Fluctuation of Relative Humidity in Museums Located in Historical Buildings     

C. Ferreira  V. P. de Freitas 《文物保护研究》2020,65(3):127-141

ABSTRACT

The preservation of artefacts in museum collections is profoundly affected by fluctuations in temperature and, especially, relative humidity (RH). Since the late nineteenth century, many studies have been carried out on the best way to control hygrothermal conditions. In old buildings located in maritime temperate climate zones (such as Portugal) with strong thermal inertia, and which have low ventilation rate (relative to the volume and number of visitors), daily and seasonal hygroscopic inertia may help to assure the maintenance of RH stabilization conditions. The use of expensive active systems may be minimized through the passive behaviour of internal finishing building materials. This work presents the results of an experimental laboratory study conducted in a flow chamber to demonstrate the enormous potential of hygroscopic materials in stabilizing interior relative humidity. Based in these results and in-situ monitoring in a museum housed in a building, located in Porto, with a typical construction of the 1950s (granite masonry and reinforced concrete slabs), a numerical analysis was done to quantify the influence of hygroscopic materials in stabilizing the interior relative humidity.  相似文献   

Introduction: Scientific and Technological Textbooks in the European Periphery     

José Ramón Bertomeu-sánchez  Antonio García-Belmar  Anders Lundgren  Manolis Patiniotis 《Science & Education》2006,15(7-8):657-665

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The energetics and benefit of an arm swing in submaximal and maximal vertical jump performance     

Lees A  Vanrenterghem J  De Clercq D 《Journal of sports sciences》2006,24(1):51-57

The aims of this study were to investigate the energy build-up and dissipation mechanisms associated with using an arm swing in submaximal and maximal vertical jumping and to establish the energy benefit of this arm swing. Twenty adult males were asked to perform a series of submaximal and maximal vertical jumps while using an arm swing. Force, motion and electromyographic data were recorded during each performance and used to compute a range of kinematic and kinetic variables, including ankle, knee, hip, shoulder and elbow joint powers and work done. It was found that the energy benefit of using an arm swing appears to be closely related to the maximum kinetic energy of the arms during their downswing, and increases as jump height increases. As jump height increases, energy in the arms is built up by a greater range of motion at the shoulder and greater effort of the shoulder and elbow muscles but, as jump height approaches maximum, these sources are supplemented by energy supplied by the trunk due to its earlier extension in the movement. The kinetic energy developed by the arms is used to increase their potential energy at take-off but also to store and return energy from the lower limbs and to "pull" on the rest of the body. These latter two mechanisms become more important as jump height increases with the pull being the more important of the two. We conclude that an arm swing contributes to jump performance in submaximal as well as maximal jumping but the energy generation and dissipation sources change as performance approaches maximum.  相似文献   

Mediating the Economic Pulses: The International Connection in Portuguese Higher Education     

Pedro Teixeira  Alberto Amaral  Maria João Rosa 《Higher Education Quarterly》2003,57(2):181-203

Portugal, as a small and increasingly integrated European economy, has been influenced by some of the major trends that defined the agenda of higher education policy in recent decades. Its backwardness – notably in terms of skills, education, and training – has frequently prompted a focus of attention on its international counterparts, particularly those in Europe, in search of affinities, solutions and errors to avoid. The search for guidance has also created an opportunity for the intervention of international organisations. Until Portugal joined the European Union (EU) in 1986, the Organisation for Economic Cooperation and Development (OECD) and the World Bank were the main agencies playing this role. Henceforth, those institutions lost some influence, and the European dimension gained increasing prominence. This article discusses the role of those international organisations in the definition of priorities for Portuguese higher education policy in recent decades, and provides a general overview of the outside perceptions of the Portuguese situation as understood by these international organisations. In particular, the article focuses on those interventions that promoted the influence of market mechanisms in the Portuguese higher education system by emphasising the need for higher education institutions (HEIs) to strive for increased economic responsiveness.  相似文献   

The scientist's code     

André Cournand  Michael Meyer 《Minerva》1976,14(1):79-96

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Language and country preponderance trends in MEDLINE and its causes.   总被引：3，自引：0，他引：3  

Alvar Loria  Pedro Arroyo 《Journal of the Medical Library Association》2005,93(3):381-385

OBJECTIVE: The authors characterized the output of MEDLINE papers by language and country of publication during a thirty-four-year time period. METHODS: We classified MEDLINE's journal articles by country of publication (Anglos/Non-Anglos) and language (English/Non-English) for the years 1966 and from 1970 to 2000 at five-year intervals. Eight English-speaking countries were considered Anglos. Linear regression analysis of number of papers versus time was performed. RESULTS: The global number of papers increased linearly at a rate of 8,142 papers per year. Anglo and English papers also increased linearly (6,740 and 9,199, respectively). Journals of Non-Anglo countries accounted for 25% of the English language increase (2,438 per year). Only Non-English papers decreased at a rate of 1,056 fewer papers per year. These trends have led to overwhelming shares of English and Anglo papers in MEDLINE. In 2000, 68% of all papers were published in the 8 Anglo countries and 90% were written in English. CONCLUSIONS: The Anglo and English preponderances appear to be a consequence of at least two phenomena: (1) editorial policy changes in MEDLINE and in some journals from Non-Anglo countries and (2) factors affecting Non-Anglo researchers in the third world (publication constraints, migration, and undersupport). These are tentative conclusions that need confirmation.  相似文献   

Spanish historic archives’ use of websites as a management transparency vehicle     

Ana R. Pacios  José Luis La Torre Merino 《Archival Science》2018,18(2):185-205

Against the backdrop of Spain’s Transparency Act, this article discusses the presence or otherwise of a series of document types, proposed as management-related transparency indicators, on 61 (8 national and 53 provincial) historic archive websites. Although examples of good practice were identified, the information provided was found to be scant, in particular as regards lines of action, organisational objectives and yearly reports. The information most commonly provided on the websites included the collection classification chart, service use regulations and citizen charters. The inference drawn was that archives, so intently focused on their role in the application of the Act by the organisations they serve, neglect their own administrative obligations in respect of its provisions. The recommendation is that as government-funded and subsidised public service institutions, historic archives should exercise transparency by furnishing the information stipulated in the Act on their websites.  相似文献   

Guide to New Resources     

Ming Fang He  Jeff Sapp  Maria José Botelho  Isabel Nuñez  Wynnetta Scott-Simmons  Lincoln Johnson 《Multicultural Perspectives》2014,16(1):53-62

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English-Spanish Cognates and the Pura Belpré Children's Award Books: Reading the Word and the World     

José A. Montelongo  Anita C. Hernández  Roberta J. Herter 《Multicultural Perspectives》2014,16(3):170-177

English-Spanish cognates are an important subset of words in both the English and Spanish languages. Cognates are words that possess identical or nearly identical spellings and meanings in both languages as a result of being derived from Latin and Greek. Of major importance is the fact that many of the more than 20,000 cognates in English are academic vocabulary words, terms essential for comprehending school texts.

?The Pura Belpré Children's Book Award has been given since 1996 to outstanding children's and young adult literature that represents, affirms, and celebrates the Latino cultural experience. The books are judged for their literary and artistic quality.

?There are many English-Spanish cognates in each of the Pura Belpré picture books. The purpose of this article is to introduce the Pura Belpré Cognate Database, which lists all of the English-Spanish cognates for each of the children's picture books that have won the award or have been designated as honor books. Ideas for vocabulary, spelling, and morphology lessons or mini-lessons are also presented.  相似文献   

No effect of acute and chronic supramaximal exercise on circulating levels of the myokine SPARC     

Preeyaphorn Songsorn  José Ruffino 《European Journal of Sport Science》2017,17(4):447-452

Myokines may play a role in the health benefits of regular physical activity. Secreted protein acidic rich in cysteine (SPARC) is a pleiotropic myokine that has been shown to be released into the bloodstream by skeletal muscle in response to aerobic exercise. As there is evidence suggesting that SPARC release may be linked to glycogen breakdown and activation of 5’ adenosine monophosphate-activated protein kinase, we hypothesised that brief supramaximal exercise may also be associated with increased serum SPARC levels. In the present study, 10 participants (3 women; mean?±?SD age: 21?±?3 y, body mass index (BMI): 22?±?3?kg?m^?2, and V˙O_2max: 39?±?6?mL?kg^?1?min^?1) performed an acute bout of supramaximal cycle exercise (20-s Wingate sprint against 7.5% of body mass, with a 1-min warm-up and a 3-min cool-down consisting of unloaded cycling). Serum SPARC levels were determined pre-exercise as well as 0, 15, and 60?min post-exercise and corrected for plasma volume change. To determine whether regular exercise affected the acute SPARC response, participants repeated the acute exercise protocol three times per week for four weeks, and serum SPARC response to supramaximal exercise was reassessed after this period. Acute supramaximal exercise significantly decreased plasma volume (?10%; p?<?.001), but was not associated with a significant change in serum SPARC levels at either the pre-training or post-training testing sessions. In conclusion, in contrast to aerobic exercise, a single brief supramaximal cycle sprint is not associated with an increase in serum SPARC levels, suggesting that SPARC release is not related to skeletal muscle glycogen breakdown.  相似文献