288 research outputs found

    Infrared study of spin crossover Fe-picolylamine complex

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    Infrared (IR) absorption spectroscopy has been used to probe the evolution of microscopic vibrational states upon the temperature- and photo-induced spin crossovers in [Fe(2-picolylamine)3]Cl2EtOH (Fe-pic). To overcome the small sizes and the strong IR absorption of the crystal samples used, an IR synchrotron radiation source and an IR microscope have been used. The obtained IR spectra of Fe-pic show large changes between high-spin and low-spin states for both the temperature- and the photo- induced spin crossovers. Although the spectra in the temperature- and photo-induced high-spin states are relatively similar to each other, they show distinct differences below 750 cm-1. This demonstrates that the photo-induced high-spin state involves microscopically different characters from those of the temperature-induced high-spin state. The results are discussed in terms of local pressure and structural deformations within the picolylamine ligands, and in terms of their possible relevance to the development of macroscopic photo-induced phase in Fe-pic.Comment: 6 pages (text) and 6 figures,submitted to J. Phys. Soc. Jp

    Teachers' resilience: conceived, perceived or lived-in

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    [Extract] Schools in Western countries are places where work related conditions lead to teacher disaffection and attrition. To mitigate this employers and scholars advocate fostering teacher resilience. This chapter presents a critical examination of teacher resilience. Originally conceived as a personal trait, later research showed human resilience is an attribute that can be developed. Resilience is one’s ability to manage stressors and maintain adaptive functioning across all domains of life. Latterly, scholars investigated resilience in teachers, mainly through qualitative or quantitative self-report studies. This research constitutes perceived teacher resilience, because as formulated, teacher resilience is conceptually flawed, limited in scope, based on teachers’ functioning within their professional lives. We do not know what constitutes long serving teachers’ actual, lived-in resilience: what enables teachers to maintain their wellbeing and effectiveness in the classroom, reflecting human resilience as originally conceived. For an accurate profile of teacher resilience we must study those still teaching, and teachers who have exited the profession to determine why they left. Perhaps exiting the profession signals a resilient person who does accept working conditions that do not support wellbeing or teaching effectiveness. Perhaps ‘teacher resilience’ is inaccurately used in the context of teacher attrition and disaffection

    Comparative genetic analysis: the utility of mouse genetic systems for studying human monogenic disease

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    One of the long-term goals of mutagenesis programs in the mouse has been to generate mutant lines to facilitate the functional study of every mammalian gene. With a combination of complementary genetic approaches and advances in technology, this aim is slowly becoming a reality. One of the most important features of this strategy is the ability to identify and compare a number of mutations in the same gene, an allelic series. With the advent of gene-driven screening of mutant archives, the search for a specific series of interest is now a practical option. This review focuses on the analysis of multiple mutations from chemical mutagenesis projects in a wide variety of genes and the valuable functional information that has been obtained from these studies. Although gene knockouts and transgenics will continue to be an important resource to ascertain gene function, with a significant proportion of human diseases caused by point mutations, identifying an allelic series is becoming an equally efficient route to generating clinically relevant and functionally important mouse models
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