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221.
Vanessa Otero Joana V. Pinto Leslie Carlyle Márcia Vilarigues Marine Cotte 《文物保护研究》2017,62(3):123-149
The Winsor & NewtonTM (W&N) nineteenth century archive database includes digitised images of hand-written instructions and workshop notes for the manufacture of their artists’ materials. For the first time, all 183 production records for yellow lead chromate pigments were studied and evaluated. They revealed that W&N produced essentially three pigment types: lemon/pale based on mixed crystals of lead chromate and lead sulphate [Pb(Cr,S)O4]; middle on pure monoclinic lead chromate [PbCrO4]; and deep that contains the latter admixed with basic lead chromate [Pb2CrO5]; accounting for 53, 22, and 21% of the production, respectively. Production records for primrose (4%) were also included since the formulation results in mixed crystals with a high percentage of lead sulphate, which, according to the literature, leaves it more prone to degradation. Each pigment type is characterised by only one or two main synthetic pathways; process variations reveal a systematic and thorough search for a high-quality durable product. A comparison of the chemical composition of pigment reconstructions with early W&N oil paint tubes showed that their records entitled ‘pale’ and ‘lemon’ correlated with the pigment in their tube labelled chrome yellow and, ‘middle’ and ‘deep’ with the label chrome deep. Lemon and middle pigment formulations were made into oil paints to assess their relative photo-stability. The degradation process was followed by colorimetry and was studied by synchrotron radiation-based techniques. Based on the X-ray absorption spectroscopy data, the possibility for creating a stability index for chrome yellows is discussed. 相似文献
222.
To assess the relevance of the Public Library System in the political agenda, programs presented by the Political Parties competing in Regional and Local elections in the Spanish Region of Castilla-La Mancha were analyzed and the proposals about these library institutions were identified.
All Regional programs were collected and also an ample sample from the Municipalities for the 2007 and 2015 elections, trying to find the differences influenced by the impact of the financial crisis and recession on the public-library policies.
The conclusion arrived at was that, although the Public Libraries may be reasonably present in the studied programs, there is a low awareness by the Political Parties of the main problems. 相似文献
223.
Metrics on open access (OA) availability of content published in scholarly journals (i.e. content licences, copyright ownership, and publisher‐stipulated self‐archiving permissions) are still scarce. This study implements the four core variables of the recently published Open Access Spectrum (OAS) (reader rights, reuse rights, copyright, and author posting rights) to measure the level of openness in all 1,728 Spanish scholarly journals listed in the Spanish national DULCINEA database at the end of 2015. Data exported from the database and used as variables for the analysis were: journal research area, type of publisher, type of access, self‐archiving and reuse policy, and type of Creative Commons (CC) licence used. Out of the total number of journals (1,728), 1,285 (74.5%) published their articles OA immediately after initial publication and thus received the maximum OAS score for reader rights; 37.5% of all journals used CC licences, and 79.5% allowed self‐archiving in some form. In 72% of journals, authors retained or publishers granted broad rights, which included author reuse and authorization rights (for others to reuse), whilst 13.5% did not specify any terms for copyright transfer. Similar studies could be carried out on other countries as this would enable comparisons of the general adoption and form of openness in different parts of the world. 相似文献
224.
This study investigated the relationship among sex, attitude toward intelligence, and self‐estimation of multiple intelligences for self and parents among Portuguese adolescents in secondary schools. Two hundred and forty‐two adolescents estimated their own and their parents' IQ scores on each of Gardner's 10 multiple intelligences: verbal (linguistic), logical (mathematical), spatial, musical, body‐kinesthetic, interpersonal, intrapersonal, existential, spiritual, and naturalistic. They also answered six simple questions concerning intelligence and intelligence tests. There were various sex differences in self‐estimated IQ: males rated themselves higher on overall, mathematical, spatial, intrapersonal, spiritual, and naturalistic IQ compared with females. Multiple regressions indicated that verbal, logical, and intrapersonal intelligence were significant predictors for self and parents overall IQ estimations. Factor analysis of the 10, the 8, and the 7 self‐estimates scores did not confirm Gardner's classification of multiple intelligences. Males were more likely to believe in sex differences in intelligence than females. Results are discussed in terms of the growing literature in the self‐estimates of intelligence, as well as limitations of that approach. 相似文献
225.
Lorenzo G. Lledó A. Pérez-Vázquez E. Lorenzo-Lledó A. 《Education and Information Technologies》2021,26(4):4111-4126
Education and Information Technologies - During the last two decades, the use of Information and Communication Technologies (ICT) has opened new paths in the intervention of people with Autism... 相似文献
226.
Carla Márquez Rodolfo Solís-Vivanco Astrid Schilmann Humberto Nicolini 《Parenting, science and practice》2021,21(1):47-54
SYNOPSIS Objective . To explore whether maternal sensitivity is associated with Autism Spectrum Disorder (ASD) severity in children with and without ASD. Design . The samples consisted of 25 Mexican dyads of children with ASD (aged 3.1-6.9 years) and their mothers (aged 20-47 years) and 24 Mexican dyads of children without ASD (aged 3.4-6.7 years) and their mothers (aged 24-45 years). Maternal sensitivity and ASD severity symptoms were scored from 2-h videos of mother-child daily interactions. Results . A between-group comparison showed a trend toward less severe ASD in children with highly sensitive mothers, specifically in the Nonverbal Communication subdomain. Conclusions . Greater maternal sensitivity is associated with improved social ability in children with ASD. 相似文献
227.
Evdokimova Olga L. Alves Carla S. Krsmanović Whiffen Radenka M. Ortega Zaida Tomás Helena Rodrigues João 《Journal of Zhejiang University. Science. B》2021,22(6):450-461
In this study, the fibers of invasive species Agave americana L. and Ricinus communis L. were successfully used for the first time as new sources to produce cytocompatible and highly crystalline cellulose nanofibers. Cellulose nanofibers were obtained by two methods, based on either alkaline or acid hydrolysis. The morphology, chemical composition, and crystallinity of the obtained materials were characterized by scanning electron microscopy(SEM) together with energy-dispersive X-ray spectroscopy(EDX), dynamic light scattering(DLS), X-ray diffraction(XRD), and Fourier transform infrared(FTIR)spectroscopy. The crystallinity indexes(CIs) of the cellulose nanofibers extracted from A. americana and R. communis were very high(94.1% and 92.7%, respectively). Biological studies evaluating the cytotoxic effects of the prepared cellulose nanofibers on human embryonic kidney 293 T(HEK293 T) cells were also performed. The nanofibers obtained using the two different extraction methods were all shown to be cytocompatible in the concentration range assayed(i.e., 0-500 μg/mL). Our results showed that the nanocellulose extracted from A. americana and R. communis fibers has high potential as a new renewable green source of highly crystalline cellulose-based cytocompatible nanomaterials for biomedical applications. 相似文献
228.
Katherine G. McDaniel Taylor Brown Caitlin C. Radford Cynthia H. McDermott Trudy van Houten Martha E. Katz Dana A. Stearns Sabine Hildebrandt 《Anatomical sciences education》2021,14(2):241-251
Anatomy education provides students with opportunities to learn structure and function of the human body, to acquire professional competencies such as teamwork, interpersonal skills, self-awareness, and to reflect on and practice medical ethics. The fulfillment of this wide potential can present challenges in courses that are part of an integrated curriculum and shorter than traditional courses. This new reality, together with students' increasing concern about the stresses within medical education, led to efforts at Harvard Medical School to implement practical steps toward an optimal learning environment in anatomy. These were based on core elements of ethical anatomy education and principles of trauma-informed care. Anatomy is conceptualized here as the “first clinical discipline,” with relational interactions between anatomical educators, medical students, and body donors/patients. Essential prerequisites for the implementation of this work were support by the medical school leadership, open partnership between engaged students and faculty, faculty coordination, and peer-teaching. Specific interventions included pre-course faculty development on course philosophy and invitations to students to share their thoughts on anatomy. Student responses were integrated in course introductions, combined with a pre-dissection laboratory visit, an introductory guide, and a module on the history and ethics of anatomy. During the course, team-building activities were scheduled, and self-reflection encouraged, for example, through written exercises, and elective life-body drawing. Students' responses to the interventions were overall positive, but need further evaluation. This first attempt of a systematic implementation of an optimal learning environment in anatomy led to the identification of areas in need of adjustment. 相似文献
229.
Marisa Raquel De Giusti Ariel Jorge Lira Gonzalo Luján Villarreal 《European Journal of Engineering Education》2008,33(5-6):587-596
Simulation is the process of executing a model that describes a system with enough detail; this model has its entities, an internal state, some input and output variables and a list of processes bound to these variables. Teaching a simulation language such as general purpose simulation system (GPSS) is always a challenge, because of the way it executes the models and the abstraction level it can achieve, very different compared with most well-known programming languages. This article presents an open source simulation framework that implements a subset of entities of GPSS, which could help students to improve the understanding of this language. This tool also stores all entities of simulations in every single simulation time, which is very useful for debugging simulations, but also for getting a detailed history of all entities in the simulations, knowing exactly how they have behaved in every simulation time. 相似文献
230.