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This paper provides new insights into understanding the causes of deterioration of the Corbii de Piatra rupestrian church and shows the significance of studying the geological environment of historical rock-cut settlements when undertaking preservation and restoration actions. The Corbii de Piatra church is one of the few rupestrian churches remaining in Romania and is an important part of the country's heritage. The church is carved in a stratum of polymictic sandstone of Oligocene age, which is part of the Getic Depression, located in the southern part of the South Carpathians. In the 14th century the interior walls of the church were decorated with mural paintings of a high artistic value. Over the centuries, the church's walls and mural paintings have been negatively affected by a series of physicochemical processes. These processes were studied through field investigations and laboratory analyses carried out between October 2007 and November 2010. The investigations revealed that tectonic fissuring and the structural anisotropy of the rock facilitate the infiltration of meteoric water through the walls into the interior of the church, from north to south, maintaining a high-level of humidity in the northern wall and in the interior of the church. The most harmful effects observed were: (i) the partial hydrolysis of the feldspars through reaction with water from the pores, producing a friable mass of phyllosilicates which led to a superficial disaggregation of the rock and to a diminished cohesion between the rock and the mortar of the fresco, (ii) the reprecipitation of the gypsum as efflorescences on the northern wall and ceiling, covering the mural painting in localized areas, as a result of the transportation of the gypsum by water from the upper strata, (iii) the alteration of the cinnabar pigment, as a result of water penetration by diffusion through the fresco from the wet rock to the pictorial layer (the secondary effect observed being the formation of sulfuric acid, which further reacted with the carbonate from the fresco to form gypsum), (iv) the development of biotic crusts, predominately algal, on the interior wet walls, which, facilitated by the permanent high humidity and the semi-obscurity of the interior of the church, have covered large surfaces of the fresco. Compared to the interior, the exterior vertical walls have been exposed to prolonged daily and seasonal variations of temperature and humidity. These variations have caused repeated variations in the volume of the sandstone, leading to contraction fissuring and peeling of the vertical walls. Any future procedures that might be used to conserve the church should strive to reduce the humidity of the sandstone in the interior walls. 相似文献
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In this introduction, we review the arguments that underpin the rationale for the special section, and provide a structured sequence for the contents of the six selected papers that comprise the section. 相似文献
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Ashley R. Alred Jennifer H. Doherty Laurel M. Hartley Cornelia B. Harris Jenny M. Dauer 《International Journal of Science Education》2013,35(12):1682-1700
ABSTRACTAn understanding of biological variation is important for understanding ecological interactions, ecosystem function, and species’ response to environmental change. Biological variation is essential to species survival because natural selection acts upon the phenotypic variation within a population: the more varied the population’s genetic resources, the more likely that the population will persist into the future. We explored how students think about biological variation by evaluating written assessments and interviews of grades 6–16 students about starting a captive breeding programme for species conservation. We created a qualitative framework that describes levels of proficiency in student ideas about biological variation. Lower level responses reason about attributes related to an individual’s reproduction and survival rather than population-level variability. Student responses at a middle level of sophistication point to the importance of variation but do not link it mechanistically to species survival and resilience. We also describe alternative conceptions related to biological variation and natural selection which exist at all grade levels. Educators can use these findings to inform curriculum and instruction in terms of addressing important concept areas (e.g. variation at the population scale) and some common alternative conceptions that may impact an accurate understanding of natural selection and evolution. 相似文献
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This article reviews the terms and concepts that have been used for describing regulation of learning during cooperative and collaborative learning and suggests differentiating them on the basis of which parts of a regulatory feedback loop model are being shared. During cooperative and collaborative learning, not only self-regulation but also the regulation of the group process is important. This regulation might occur on both an individual level and a social level. Several modes of regulation have been identified, but the terms used for them vary tremendously—including social regulation, socially shared regulation, coregulation, and other-regulation. This article seeks to clarify the diverse terminology. To this end, we use a theoretical framework based on Winne and Hadwin's (1998) model of self-regulated learning to analyze how the different terms are used in the literature. We make and exemplify suggestions for a consistent usage of terms. 相似文献
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Dietrich Boles Markus Dreger Kai Gro?johann Cornelia Haber Andreas Kusserow Stefan Lohrum Dirk Menke Jochen Meyer Gerhard M?ller und Ricarda Weber 《Informatik - Forschung und Entwicklung》1998,13(3):110-121
Zusammenfassung. Ziele des MeDoc-Projektes waren die Konzeption, prototypische Entwicklung und Erprobung volltextbasierter Informations- und
Publikationsdienste für die Informatik, um den Informationsaustausch und die Literaturversorgung in der Wissenschaft effektiver
gestalten zu k?nnen. Dazu wurde im Rahmen des Projektes ein internet-basiertes System entwickelt, in dem Informatik & Fachinformation
im Volltext gespeichert, recherchiert, abgerufen und gelesen werden kann und das die Suche nach Informatik-Literatur in heterogenen,
verteilten Informationsquellen im Internet unterstützt. Das Informationsangebot ist dabei teilweise kostenpflichtig. In diesem
Artikel werden Ziele, Funktionalit?t und Architektur des MeDoc-Systems beschrieben.
Eingegangen am 19. Januar 1998 / Angenommen am 27. April 1998 相似文献
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Cristiane Maria Cornelia Gottschalk 《Educational Philosophy and Theory》2018,50(5):469-477
AbstractFrom a Wittgensteinian point of view, my goal is to argue against the idea that teaching critical thinking should have as one of its aims the possibility of changing or adapting our deeply held beliefs. As pointed out by the Austrian philosopher in On Certainty, we have a world-picture which is neither true nor false, but above all, ‘it is the substratum of all my enquiring and asserting’ (OC, §162). Besides that, in his remarks on Frazer’s Golden Bough, Wittgenstein insists on the idea that different communities have their own rituals that express ways of acting, which become crystallized in their customs and institutions, similar to the magical rituals described by Frazer. The degree of similarity among them is greater than we suspect, and what interested Wittgenstein was to understand how we see things by looking for the links between the various ritualistic events. Based on these remarks, I argue that, if our deeply held beliefs are a source of necessity, instead of aiming to change/adapt them, teaching critical thinking should—by showing the links between diverse cultures—essentially avoid employing them in a dogmatic way, since our own deeply held beliefs could have been different ones. 相似文献
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This study raises the question what makes school texts comprehensible by analyzing whether students’ genre expectations about literary or expository texts moderate the impact of different forms of text cohesion on reading comprehension, even when the texts are similar regarding their genre. 754 students (Grade 9) from comprehensive schools read one of four text versions with similar content, but different degrees of local and global text cohesion. The four more or less cohesive texts were introduced as literary texts (part of a story) or as expository texts (newspaper article), although the different genres were only purported and the texts contained both literary and expository passages. Reading comprehension was assessed with multiple-choice-items, semi-open, and open-ended questions. Results demonstrate that global cohesion was profitable for reading comprehension with expository expectations, but not with literary ones. Local text cohesion and both forms of cohesion in combination did not interact with students’ genre expectations and had no main effect on comprehension. When students reading skills and prior knowledge were considered, the interaction was still apparent. Moreover, students with lower levels of reading skills tended to profit especially from texts with global cohesion, whereas the readers with higher reading skills achieved equal means in reading comprehension irrespective of the degree of global text cohesion. The findings are discussed with respect to theoretical aspects of text–reader-interactions, cognitive and emotional components of genre expectations, and the composition and instruction of comprehensible school texts. 相似文献
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Learning from worked examples is an effective learning method in well-structured domains. Can its effectiveness be further enhanced when errors are included? This was tested by determining whether a combination of correct and incorrect solutions in worked examples enhances learning outcomes in comparison to correct solutions only, and whether a mixture of correct and incorrect solutions is more effective when the errors are highlighted. In addition, the effectiveness of fostering self-explanations was assessed. In Experiment 1, the participants learned to solve probability problems under six conditions that constituted a 2 × 3-factorial design (Factor 1: correct and incorrect solutions with highlighting the errors vs. correct and incorrect solutions without highlighting the errors vs. correct solutions only; Factor 2: prompting written self-explanations vs. no prompts). An aptitude-treatment interaction was found: providing correct and incorrect solutions fostered far transfer performance if learners had favourable prior knowledge; if learners had poor prior knowledge correct solutions only were more favourable. Experiment 2 replicated this interaction effect. Thus, a mixture of correct and incorrect solutions in worked examples enhanced learning outcomes only for “good” learners. In addition, Experiment 2 showed that confronting learners with incorrect solutions changed the quality of their self-explanations: on the one hand, new types of effective self-explanations could be observed, but on the other hand the amount of the very important principle-based self-explanations was substantially reduced. A possible measure to prevent this negative side effect of incorrect solutions is discussed. 相似文献