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1.
ABSTRACT

Previously, heavy use of biocides for the treatment of objects made of organic materials in museum collections (e.g. ethnographic, historical collections) was very common. Now suitable decontamination methods/technologies are being sought. A decontamination treatment by li-CO2 was optimized that considered the specific requirements of museum objects. The treatment was tested on model materials artificially contaminated with biocide solutions containing dichlorodiphenyltrichloroethane (DDT), pentachlorophenol (PCP), lindane, and permethrin or cypermethrin. High decontamination was achieved for DDT, lindane, PCP, and permethrin on artificially biocide loaded wool and wood model materials. Optimal process parameter settings for li-CO2 decontamination include a single 30?min cycle for woolen materials and three sequential 30?min cycles each for wood. These methods allow a reduction of at least 90% of all biocides for wool and between 70% and 85% for wood. Decontamination of the latter was more effective for less polar biocides as DDT and permethrin. Despite a significant improvement in decontamination for wood using co-solvents such as acetone, ethanol, and methyl tertiary-butyl ether (MTBE), their use is not recommended due to the increased risk of damage to the objects, in particular if a surface coating is present.  相似文献   
2.
Johann  David  Mayer  Sabrina Jasmin 《Minerva》2019,57(2):175-196
Minerva - We extend previous research by systematically investigating whether perceptions of scientific authorship vary between domains. Employing regulations for authorship of scientific journals...  相似文献   
3.
达勒姆(Dahlem)不仅仅是一个传奇.在德国,几乎没有其他地方像柏林的这片土地那样,在科学史各个丰富的方面--包括令人质疑的方面--表现出如此强烈的活力.在马普学会历史档案馆馆长亨宁(Eckart Henning)的陪同下巡游他的“领地“,就如同在历史的时光中漫步,著名学者的创新精神始终伴随着我们的游程.……  相似文献   
4.
In this article, we present an approach for comprehensive analysis of the effectiveness of interventions based on nonlinear structural equation mixture models (NSEMM). We provide definitions of average and conditional effects and show how they can be computed. We extend the traditional moderated regression approach to include latent continous and discrete (mixture) variables as well as their higher order interactions, quadratic or more general nonlinear relationships. This new approach can be considered a combination of the recently proposed EffectLiteR approach and the NSEMM approach. A key advantage of this synthesis is that it gives applied researchers the opportunity to gain greater insight into the effectiveness of the intervention. For example, it makes it possible to consider structural equation models for situations where the treatment is noneffective for extreme values of a latent covariate but is effective for medium values, as we illustrate using an example from the educational sciences.  相似文献   
5.
The concept of assimilation-to-schema proposes that learning depends on three conditions: (1) the reception of the to-be-learned material, (2) the availability of a cognitive structure to which the new material may be assimilated, (3) the activation of the structure during learning. The concept provides weak (i.e., concerning amount of learning) and strong (i.e. concerning the structure of learning outcomes) predictions with respect to the effects of sequencing of instruction, ordering of instruction and organization of instruction. The present review demonstrates that studies of the role of instructional sequencing provide an important test of the assimilation-to-schema theory, and that many apparent inconsistencies in the literature may be better understood by an analysis of the internal assimilation process.This paper was partially supported by a Faculty Research Grant from the Academic Senate of the University of California, Santa Barbara.  相似文献   
6.
Teacher nominations are often used in school settings to identify gifted children. However, although high intelligence is part of almost all definitions of giftedness, prior research has consistently shown that not all children nominated as gifted by teachers have high intelligence. In order to further understand the characteristics of these students, we herein explore the role of another cognitive construct, namely working memory (WM). In a sample comprising N = 81 fourth graders, both WM and intelligence showed the same predictive value for characterizing teacher-nominated gifted children, pointing to the importance of the thus-far-unattended WM for characterizing these students.  相似文献   
7.
Phonics, fluency, and reading strategy trainings are evidence-based interventions that foster the reading skills of poor readers in primary school. The purpose of the present study was to compare differential effects of the three types of trainings on the efficiency of component processes on word, sentence, and text level immediately after the training and at a 3-month follow-up. The 235 poor readers were randomly allocated to one of the reading interventions or to a control condition. All interventions consisted of 25 sessions that were scheduled twice a week and lasted 45 min. Results indicated short-term effects of the phonics training and the strategy training on the efficiency of a broad range of word-level and sentence-level processes. None of the treatment effects persisted over the long term, indicating the need for instructional efforts to regularly practice the acquired skills after the actual training.  相似文献   
8.
The integrative curriculum combines subject‐matter studies, mini‐courses, and long term projects which allows for individual differences and provides a qualitatively different instruction program for the gifted.  相似文献   
9.
Based on newly assembled survey data, we analyze which individual characteristics of IT employees are associated with the willingness to participate voluntarily in Open Source Software (OSS) projects. We find that, contrary to common expectations, formal educational attainment is not positively associated with the probability or level of OSS contributions. The group of university dropouts, however, does show a particularly high probability of working on such projects. Furthermore, we obtain the striking and novel finding that work-related OSS activities play an important role in determining voluntary OSS contributions during leisure time. Although one has to be cautious regarding the direction of causality, we interpret this as evidence of career-oriented motives in voluntary OSS contributors. The finding is also reinforced by our more specific analysis of the importance of such motives in determining the actual effort invested in OSS projects.  相似文献   
10.
In his thought-provoking review of current trends in educational research, Winn offers advice to practitioners and to researchers concerning the role of computer-based simulations in education (Winn, W. (2000). Educ. Psychol. Rev. 14, 331–351). In this critique, I offer two proposals for consideration by those who wish to make practical recommendations about learning environments: (1) Recommendations for practice should be based on specifically relevant evidence. (2) The available methods for collecting evidence should not exclude controlled experiments; instead, researchers should be free to choose among experimental or observational methods, use quantitative or qualitative measures, focus on artificial or naturalistic settings, and invent new techniques as needed. In short, I join the call for evidence-based practice and issue-driven research.  相似文献   
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