Environmentally-induced stone decay: the cumulative effects of crystallization–hydration cycles on a Lincolnshire oopelsparite limestone     

Belinda J. Colston  David S. Watt  Helen L. Munro   《Journal of Cultural Heritage》2001,2(4)

An investigation has been undertaken at St Andrew’s church, Walpole St Andrew, Norfolk, to establish the underlying causes of the observed stone decay to the upper parts of the six stone piers. The stone decay was first recorded in the early 1930s. The salt-contaminated masonry within the church has been shown to undergo severe salt decay during the summer, with little damage occurring over the winter months. The south aisle piers have been shown to decay 2.5 times faster than the north aisle piers. Although crystallization–hydration cycles have been identified, the rate of decay is at its greatest when the cycling is relatively infrequent. This was not the expected trend. Furthermore, it has been shown that during extended periods where the ambient relative humidity is less than 75%, the rate of decay reaches a maximum. It is the length of this ‘drying’ period that apparently has the greatest influence on the rate of decay and could explain the significant difference in the rate of decay between the south and north aisle piers. The results have serious implications for passive conservation, where it is often recommended to lower the ambient relative humidity to well below the equilibrium relative humidity of the salt contaminant, to avoid crystallization–hydration cycles. Since, at the time of building, the church was situated on the coast, it is possible that the sodium chloride contamination occurred during the building process (1440–1520), particularly since the area was prone to sea-flooding at this time. Alternatively, the salt could have been applied as a treatment during the general restoration of 1897. Whatever the source of the salt, it seems likely that the ambient environment was changed by the insertion of a sealed floor in 1897, which could account for the onset of the salt decay.  相似文献   

Change management and the SENCo role: developing key performance indicators in the strategic development of inclusivity     

Liz Done  Mike Murphy  Mia Watt 《Support for Learning》2016,31(4):281-295

This article follows an earlier publication highlighting the changing role of special educational needs co‐ordinators (SENCos) in England. SENCos are now required to manage change strategically and deliver inclusive school cultures. School‐based action research undertaken by a teacher studying for the postgraduate National Award for SEN Co‐ordination (NASENCO) is featured in the article; a strategic review of resource allocation increased the availability and quality of interventions for students with special educational needs and disabilities (SEND). The commentary which frames the study acknowledges that many SENCos are not yet members of a senior school management team (SMT) despite their mandated strategic whole‐school remit. Featuring the process through which one SENCo has strived to enhance SEND provision and develop context‐specific key performance indicators brings official guidance on the SENCo's role in strategic change management into sharp focus, raising questions that should concern both SMTs and non‐SMT SENCos.  相似文献   

Differing Roles,Differing Concerns: Using Network Analysis as a Tool to Highlight Diverging Concerns and Priorities Surrounding Teacher Education at Minority-Serving Institutions     

Dorothy Villarreal  Manuel González Canché  Andrés Castro Samayoa  Alice Ginsberg 《The Teacher Educator》2013,48(4):446-459

Abstract

Minority-serving institutions are important in the production of teachers of color. However, this formative process is not without limitations. This multisite, multistate study relied on network analysis techniques to unveil timely and relevant concerns that students, faculty, and administrators identified as critical toward the strengthening of teacher production.  相似文献   

Contemporary Scientists and their Interactions with Non-Scientists: Alternative Companion Stories for School Curricula     

Smith  Dorothy V.  Mulhall  Pamela J.  Hart  Christina E.  Gunstone  Richard F. 《Research in Science Education》2020,50(5):2111-2130

Research in Science Education - Students learn more than science knowledge in a science classroom; they also acquire important messages about the purposes and contexts of science. Roberts (2011)...  相似文献   

The Bicycle Assembly Line Game     

Dorothy Klotz 《Decision Sciences Journal of Innovative Education》2011,9(3):371-377

“The Bicycle Assembly Line Game” is a team‐based, in‐class activity that helps students develop a basic understanding of continuously operating processes. Each team of 7–10 students selects one of seven prefigured bicycle assembly lines to operate. The lines are run in real‐time, and the team that operates the line that yields the highest revenue wins. Students learn through discovery “What drives output rate?”; “How is capacity managed relative to market demand?”; and “Why does inventory accumulate?” Because task times are constant, the game provides a nice lead‐in to the topic of line balancing. This game has been successfully used in both undergraduate‐ and MBA‐level operations management courses.  相似文献   

How to doctor the media     

Nelkin D 《New scientist (1971)》1986,112(1535):51-56

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Genetic influences in different aspects of language development: the etiology of language skills in 4.5-year-old twins     

Kovas Y  Hayiou-Thomas ME  Oliver B  Dale PS  Bishop DV  Plomin R 《Child development》2005,76(3):632-651

The genetic and environmental etiologies of diverse aspects of language ability and disability, including articulation, phonology, grammar, vocabulary, and verbal memory, were investigated in a U.K. sample of 787 pairs of 4.5-year-old same-sex and opposite-sex twins. Moderate genetic influence was found for all aspects of language in the normal range. A similar pattern was found at the low end of the distribution with the exception of two receptive measures. Environmental influence was mainly due to nonshared factors, unique to the individual, with little influence from shared environment for most measures. Genetic and environmental influences on language ability and disability are quantitatively and qualitatively similar for males and females.  相似文献   

Effect of Rasch Calibration on Ability and DIF Estimation in Computer-Adaptive Tests     

Rebecca Zwick  Dorothy T. Thayer  Marilyn Wingersky 《Journal of Educational Measurement》1995,32(4):341-363

In a previous simulation study of methods for assessing differential item functioning (DIF) in computer-adaptive tests (Zwick, Thayer, & Wingersky, 1993, 1994), modified versions of the Mantel-Haenszel and standardization methods were found to perform well. In that study, data were generated using the 3-parameter logistic (3PL) model and this same model was assumed in obtaining item parameter estimates. In the current study, the 3PL data were used but the Rasch model was assumed in obtaining the item parameter estimates, which determined the information table used for item selection. Although the obtained DIF statistics were highly correlated with the generating DIF values, they tended to be smaller in magnitude than in the 3PL analysis, resulting in a lower probability of DIF detection. This reduced sensitivity appeared to be related to a degradation in the accuracy of matching. Expected true scores from the Rasch-based computer-adaptive test tended to be biased downward, particularly for lower-ability examinees  相似文献   

Children's ideas about evaporation     

Terry Russell  Wynne Harlen  Dot Watt 《International Journal of Science Education》2013,35(5):566-576

This article reports on research conducted as part of the Primary Science Processes and Concept Exploration (space) Project. The background to, and orientation of, space is briefly described.

Classroom‐based research into children's thinking about evaporation is reported. This work was conducted in close collaboration with teachers of the 5‐11 years age range with the intention of establishing the viability of the techniques for eliciting ideas and managing subsequent interventions within classrooms.

Children's thinking in relation to three main evaporation phenomena are discussed. Ideas about evaporation were categorized by reference to notions of conservation, change of location and change of form of the water.  相似文献   

Changing the conception of mathematical knowledge in intellectually able,math avoidant women     

Dorothy D. Buerk Ed.D. 《Roeper Review》2013,35(4)

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