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The aim of the work is to set up a methodological approach to verify the effectiveness of the treatments of decayed waterlogged archaeological wood and to point out the proper thermo-hygrometric conditions for its preservation after treatment. The treatments were performed on wood samples of maritime pine (Pinus pinaster Aiton), oak (Quercus sp. caducifolia), elm (Ulmus cf. minor) and strawberry tree (Arbutus unedo L.), obtained from stems pertaining to the original vegetation found in the excavation site of the Ancient Ships in Pisa (Italy), and dated from seventh century BC to second century AD The utilised products were: Polyethylene Glycols (PEG) of various molecular weights, a Polypropylene Glycol (PPG 425), Trehalose (α-D-glucopyranosyl-α-D-glucopyranoside), and their mixtures, and also a Hydroxypropylcellulose (Klucel). The main objective to be pursued by the treatments was considered the stabilisation of the original size and shape of samples. The various steps of this approach were: the execution of a preliminary diagnostic survey on untreated samples; the characterisation of treatment solutions ‘as such’ to establish the property to be monitored during the treatment; the evaluation of the main physical characteristics of wood after the treatment were determined. Among the latter, the coefficient of dimensional stability during the exposure to a series of selected thermo-hygrometric conditions and the retention of consolidants after the treatment. These two measurements allowed the definition of the ‘efficacy of a treatment’, φT, a new parameter firstly utilised in this work. It measures the stabilisation capability of the percent unit of retained product, and its value permits to put in evidence the consolidants that stabilise wood with the lowest amount of product. Conversely, it was not possible to measure the Anti-Shrink Efficiency (ASE), one of the most utilised parameters for the evaluation of treatments, because of the serious distortions and fractures observed in all the heavily degraded untreated samples.  相似文献   
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We believe that science journals can be used in the preschool classroom as tools for supporting and assessing children’s learning of science- and literacy-relevant content and procedures. To support this argument, we review changes in attitudes about the cognitive competencies of preschoolers and in teaching and learning expectations for early childhood education. We describe practical aspects of using science notebooks with this age group and discuss specific ways that journals support children’s learning. Finally, the role of journals in assessment is discussed.  相似文献   
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Endophytic flora plays a vital role in the colonization and survival of host plants, especially in harsh environments, such as arid regions. This flora may, however, contain pathogenic species responsible for various troublesome host diseases. The present study is aimed at investigating the diversity of both cultivable and non-cultivable endophytic fungal floras in the internal tissues (roots and leaves) of Tunisian date palm trees (Phoenix dactylifera). Accordingly, 13 isolates from both root and leaf samples, exhibiting distinct colony morphology, were selected from potato dextrose agar (PDA) medium and identified by a sequence match search wherein their 18S–28S internal transcribed spacer (ITS) sequences were compared to those available in public databases. These findings revealed that the cultivable root and leaf isolates fell into two groups, namely Nectriaceae and Pleosporaceae. Additionally, total DNA from palm roots and leaves was further extracted and ITS fragments were amplified. Restriction fragment length polymorphism (RFLP) analysis of the ITS from 200 fungal clones (leaves: 100; roots: 100) using HaeIII restriction enzyme revealed 13 distinct patterns that were further sequenced and led to the identification of Alternaria, Cladosporium, Davidiella (Cladosporium teleomorph), Pythium, Curvularia, and uncharacterized fungal endophytes. Both approaches confirmed that while the roots were predominantly colonized by Fusaria (members of the Nectriaceae family), the leaves were essentially colonized by Alternaria (members of the Pleosporaceae family). Overall, the findings of the present study constitute, to the authors’ knowledge, the first extensive report on the diversity of endophytic fungal flora associated with date palm trees (P. dactylifera).  相似文献   
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A variety of causes are responsible for a lack in promoting movement in German nursing homes. In this regard, research on resources holds the promise of a lasting capacity to act and should therefore be understood as a paradigm of gerontology of sports. The purpose of this paper is to make a contribution to theoretically and conceptually based approaches for operationalizing resources that promote motor abilities. Methodologically, different instruments are demonstrated that are able to assess the theoretical constructs “movement acitivity” and “influencing factors” as a basis for the subsequent analysis. Finally, a model that identifies resources is presented. It focuses on different personal and environmental factors as well as their interdependencies influencing the movement activity. The model analyzes resources and barriers to everyday movements. In this way, fundamental theoretical points of reference for research activity are shown.  相似文献   
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Questionnaire data from the PIRLS 2006 study in Italy provided a number of indices in order to summarize factors of educational context influencing reading achievement. The aim of the present paper is to study the relationships between school factors, teacher factors, family factors, student factors and reading achievement by means of multilevel regression analysis. Results show that pupils' attainment in reading is significantly related to: (1) home educational resources (home/student level effect); (2) parents' attitudes toward reading (home/student level effect); (3) students' attitudes toward reading; (4) students' reading self-concept; and (5) teacher career satisfaction (school/teacher level).  相似文献   
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Steigende Softwareumf?nge und die damit einhergehende Komplexit?tssteigerung erfordern neue Herangehensweisen an die Entwicklung eingebetteter Fahrzeugsoftware. Als Reaktion auf diese Herausforderungen vollzieht sich seit einigen Jahren ein Paradigmenwechsel von der klassischen Programmentwicklung hin zu modellbasierten Techniken. Der Beitrag gibt einen überblick über den Einsatz modellbasierter Entwicklungstechniken bei DaimlerChrysler und zeigt aktuelle Forschungsschwerpunkte auf. The growing amount of software and attendant rise in complexity demand new approaches to the development of embedded vehicle software. For some years now, a paradigm change from classical program development to model-based techniques has been taking place in reaction to these challenges. This paper provides an overview of the application of model-based development techniques at DaimlerChrysler and presents the main foci of current research.
CR Subject Classification D.2.1,D.2.2,D.2.3,D.2.5,D.2.10,I.6.4,I.6.5  相似文献   
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ABSTRACT

This article critically analyses the recent developments and changes towards Inclusive Education in Portugal, through a policy analysis that includes the last three legislative frameworks. These policies will be analysed within their cultural and historical context, to explore the similarities and differences in the conceptualisations of diversity and inclusion; and the influence of international policies in the national policies that regulate the Portuguese schools’ role in ensuring education for all. The 2018 policies aim to ensure that all students, regardless of their personal and social situation, have access and participate in an inclusive school, which aligns with the Salamanca Statement and Framework for Action (1994).  相似文献   
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