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Action Learning, Action Research, and Process Management Association (ALARPM) is an organization of volunteers dedicated to the international expansion of action learning, action research, and process management, through world congresses. It has existed for over a dozen years now, despite significant stresses and strains, and has successfully conducted five world congresses with a sixth one in 2003. This history of ALARPM shows that a small group can set out to be international and inclusive from the beginning, so long as it also develops processes to sustain itself internally.  相似文献   
2.
In mammals, the DNA methyltransferase 1 (Dnmt1) faithfully copies the pattern of cytosine methylation at CpG sites to the newly synthesized strand, and this is essential for epigenetic inheritance. In Arabidopsis thaliana, several DNA methyltransferases or chromatin modifiers coupled to methylation changes have been characterized, and mutations that cause loss of their function are recessive. This is surprising because plant gametogenesis includes postmeiotic DNA replication in haploid nuclei before fertilization. Therefore, the recessive character of the mutations excludes the affected components from a regulatory role in postmeiotic maintenance or modification of epigenetic states. Here we show, however, that depletion of A. thaliana MET1, a homolog of mammalian Dnmt1 (ref. 8), results in immense epigenetic diversification of gametes. This diversity seems to be a consequence of passive postmeiotic demethylation, leading to gametes with fully demethylated and hemidemethylated DNA, followed by remethylation of hemimethylated templates once MET1 is again supplied in a zygote.  相似文献   
3.
Our purpose in this paper is to contribute to the field of systemic practice by sharing a process of professional learning based on meta-action research. The process emerged as we engaged with evaluation data from a leadership development program (LDP). The aim of this LDP had been to help leaders design their team projects on poverty reduction through action research methods in six African countries. As facilitators of the program we discuss our experiential learning based on critical reflection. We explain how meta-action research can transform understandings of ways to improve professional practice in future applications. We present three process models: (1) a model of reflection on action, (2) a meta-action research model, and (3) a model for lifelong learning through meta-action research. These models may be of benefit and interest to readers who facilitate systemic practice and action research in education, higher education, communities, industry and government.  相似文献   
4.
Polyploidization is found frequently in plants, and species previously considered to be diploid may show remnants of earlier polyploidization events on closer inspection of their genomes. The success of polyploids may lie in increased genetic redundancy supporting subsequent genetic diversification. Although doubling the genome does not generate diversity per se, recent studies show that rapid genomic rearrangements and changes in DNA modification and gene expression patterns are associated with polyploid formation. But recessive modifications will not become phenotypically apparent in early polyploid generations. Here we show that epialleles in tetraploid plants (but not in diploids) interact in trans and lead to heritable gene silencing persisting after segregation from the inactivating allele. This mechanism, resembling paramutation, leads to the establishment of functional epigenetic homozygosity and, thus, to conversion of new recessive alleles into traits expressed in early polyploid generations. Such interactions probably contribute to rapid adaptation and evolution of polyploid plant species.  相似文献   
5.
This paper identifies the quality characteristics of a professional development (PD) program on action research (AR) and presents the results of a second-order evaluation of such a program. Three case examples in South African higher education demonstrate how AR methodology has been applied to design, conduct and evaluate the PD program and to identify new ways of learning and improving professional practice in higher education. From data analysis, we distinguish six factors significant in contributing to the quality of the PD program in all three universities: facilitator expertise, adaptive planning, responsive evaluation, critical events, application, and self-efficacy. On the basis of the evaluation results, we present five models: (1) the AR workshop cycles; (2) characteristics of a quality PD program; (3) a PD program on and through AR; (4) three levels of reflection on AR; and (5) meta-action research.
Margaret A. FletcherEmail:
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