Learning within sustainable educational innovation:An analysis of teachers' perceptions and leadership practice

Innovative initiatives in education often have problems with their sustainability. The present study focuses on three educational innovations that have proved to be sustainable over time. We used a qualitative research approach to study and identify essential features of sustainable educational innovation. Two theoretical frameworks were used to guide the study: the integrated model for sustainable innovation (IMSI) and self-determination theory (SDT). Both frameworks take a different perspective upon learning; IMSI presents learning at the individual level, the team level and the organizational level to be the heart of sustainable innovation, and SDT presents how learning can be improved. The research question focused upon how the SDT concepts of autonomy, competence and relatedness were perceived within sustainable innovation, expressed by the IMSI framework, by teachers and school leaders. Based on our findings we demonstrate that the framework of IMSI and SDT can effectively be applied as a frame of analysis to identify essential features of sustainability in educational innovations and we discuss how concepts of SDT deepen the knowledge of sustainable educational innovation

A bacterial acetyltransferase triggers immunity in Arabidopsis thaliana independent of hypersensitive response

Type-III secreted effectors (T3Es) play critical roles during bacterial pathogenesis in plants. Plant recognition of certain T3Es can trigger defence, often accompanied by macroscopic cell death, termed the hypersensitive response (HR). Economically important species of kiwifruit are susceptible to Pseudomonas syringae pv. actinidiae (Psa), the causal agent of kiwifruit bacterial canker. Although Psa is non-pathogenic in Arabidopsis thaliana, we observed that a T3E, HopZ5 that is unique to a global outbreak clade of Psa, triggers HR and defence in Arabidopsis accession Ct-1. Ws-2 and Col-0 accessions are unable to produce an HR in response to Pseudomonas-delivered HopZ5. While Ws-2 is susceptible to virulent bacterial strain Pseudomonas syringae pv. tomato DC3000 carrying HopZ5, Col-0 is resistant despite the lack of an HR. We show that HopZ5, like other members of the YopJ superfamily of acetyltransferases that it belongs to, autoacetylates lysine residues. Through comparisons to other family members, we identified an acetyltransferase catalytic activity and demonstrate its requirement for triggering defence in Arabidopsis and Nicotiana species. Collectively, data herein indicate that HopZ5 is a plasma membrane-localized acetyltransferase with autoacetylation activity required for avirulence. ? 2017 The Author(s).115Ysciescopu

Genomic analysis of the kiwifruit pathogen Pseudomonas syringae pv. actnidiae provides insight into the origins of an emergent plant disease

The origins of crop diseases are linked to domestication of plants. Most crops were domesticated centuries – even millennia – ago, thus limiting opportunity to understand the concomitant emergence of disease. Kiwifruit (Actinidia spp.) is an exception: domestication began in the 1930s with outbreaks of canker disease caused by P. syringae pv. actinidiae (Psa) first recorded in the 1980s. Based on SNP analyses of two circularized and 34 draft genomes, we show that Psa is comprised of distinct clades exhibiting negligible within-clade diversity, consistent with disease arising by independent samplings from a source population. Three clades correspond to their geographical source of isolation; a fourth, encompassing the Psa-V lineage responsible for the 2008 outbreak, is now globally distributed. Psa has an overall clonal population structure, however, genomes carry a marked signature of within-pathovar recombination. SNP analysis of Psa-V reveals hundreds of polymorphisms; however, most reside within PPHGI-1-like conjugative elements whose evolution is unlinked to the core genome. Removal of SNPs due to recombination yields an uninformative (star-like) phylogeny consistent with diversification of Psa-V from a single clone within the last ten years. Growth assays provide evidence of cultivar specificity, with rapid systemic movement of Psa-V in Actinidia chinensis. Genomic comparisons show a dynamic genome with evidence of positive selection on type III effectors and other candidate virulence genes. Each clade has highly varied complements of accessory genes encoding effectors and toxins with evidence of gain and loss via multiple genetic routes. Genes with orthologs in vascular pathogens were found exclusively within Psa-V. Our analyses capture a pathogen in the early stages of emergence from a predicted source population associated with wild Actinidia species. In addition to candidate genes as targets for resistance breeding programs, our findings highlight the importance of the source population as a reservoir of new disease

Development and test of 21 multiplex PCRs composed of SSRs spanning most of the apple genome

A series of 21 multiplex (MP) polymerase chain reactions containing simple sequence repeat (SSR) markers spanning most of the apple genome has been developed. Eighty-eight SSR markers, well distributed over all 17 linkage groups (LGs), have been selected. Eighty-four of them were included in 21 different MPs while four could not be included in any MPs. The 21 MPs were then used to genotype approximately 2,000 DNA samples from the European High-quality Disease-Resistant Apples for a Sustainable agriculture project. Two SSRs (CH01d03 and NZAL08) were discarded at an early stage as they did not produce stable amplifications in the MPs, while the scoring of the multilocus (ML) SSR Hi07d11 and CN44794 was too complex for large-scale genotyping. The testing of the remaining 80 SSRs over a large number of different genotypes allowed: (1) a better estimation of their level of polymorphism; as well as of (2) the size range of the alleles amplified; (3) the identification of additional unmapped loci of some ML SSRs; (4) the development of methods to assign alleles to the different loci of ML SSRs and (5) conditions at which an SSR previously described as ML would amplify alleles of a single locus to be determined. These data resulted in the selection of 75 SSRs out of the 80 that are well suited and recommended for large genotyping project

Phenotypic Variation and Bistable Switching in Bacteria

Microbial research generally focuses on clonal populations. However, bacterial cells with identical genotypes frequently display different phenotypes under identical conditions. This microbial cell individuality is receiving increasing attention in the literature because of its impact on cellular differentiation, survival under selective conditions, and the interaction of pathogens with their hosts. It is becoming clear that stochasticity in gene expression in conjunction with the architecture of the gene network that underlies the cellular processes can generate phenotypic variation. An important regulatory mechanism is the so-called positive feedback, in which a system reinforces its own response, for instance by stimulating the production of an activator. Bistability is an interesting and relevant phenomenon, in which two distinct subpopulations of cells showing discrete levels of gene expression coexist in a single culture. In this chapter, we address techniques and approaches used to establish phenotypic variation, and relate three well-characterized examples of bistability to the molecular mechanisms that govern these processes, with a focus on positive feedback.

Differential Phagocytosis of White versus Opaque Candida albicans by Drosophila and Mouse Phagocytes

The human fungal pathogen Candida albicans resides asymptomatically in the gut of most healthy people but causes serious invasive diseases in immunocompromised patients. Many C. albicans strains have the ability to stochastically switch between distinct white and opaque cell types, but it is not known with certainty what role this switching plays in the physiology of the organism. Here, we report a previously undescribed difference between white and opaque cells, namely their interaction with host phagocytic cells. We show that both Drosophila hemocyte-derived S2 cells and mouse macrophage-derived RAW264.7 cells preferentially phagocytose white cells over opaque cells. This difference is seen both in the overall percentage of cultured cells that phagocytose white versus opaque C. albicans and in the average number of C. albicans taken up by each phagocytic cell. We conclude that susceptibility to phagocytosis by cells of the innate immune system is an important distinction between white and opaque C. albicans, and propose that one role of switching from the prevalent white form into the rarer opaque form may be to allow C. albicans to escape phagocytosis

N-Acetylglucosamine Induces White to Opaque Switching, a Mating Prerequisite in Candida albicans

To mate, the fungal pathogen Candida albicans must undergo homozygosis at the mating-type locus and then switch from the white to opaque phenotype. Paradoxically, opaque cells were found to be unstable at physiological temperature, suggesting that mating had little chance of occurring in the host, the main niche of C. albicans. Recently, however, it was demonstrated that high levels of CO2, equivalent to those found in the host gastrointestinal tract and select tissues, induced the white to opaque switch at physiological temperature, providing a possible resolution to the paradox. Here, we demonstrate that a second signal, N-acetylglucosamine (GlcNAc), a monosaccharide produced primarily by gastrointestinal tract bacteria, also serves as a potent inducer of white to opaque switching and functions primarily through the Ras1/cAMP pathway and phosphorylated Wor1, the gene product of the master switch locus. Our results therefore suggest that signals produced by bacterial co-members of the gastrointestinal tract microbiota regulate switching and therefore mating of C. albicans

Invoering van een gedigitaliseerde onderwijspraktijk - Deel A : Patronen van interventies in een model van organisatieleren en leiderschapspraktijken in samenwerking met Henk Verbeeten

Outcomes of educational changes are often disappointing. It’s difficult implementing complex educational changes in such a way that they result in institutionalization. The research literature presents the conflicting demands from the school environment combined with the complexity of the many factors that influence each other in the innovation process as a possible explanation for this. The final goal of this research study is to determine which combination of factors is needed in order to successfully implement a complex innovation. Therefore, the research question of the dissertation is: “How do school organizations manage to influence the image that teachers have in their minds concerning the digitalization of education and the use of digital learning materials in such a way that a form of institutionalizing, that is in agreement with the principles on which the strategic change policy of the school is founded, is taking place?” The research study is designed as an explanatory case study of six secondary schools. These schools work to improve education through a wide use of ict resources. In these schools it is determined, over a longer period of time, whether teachers use digital learning materials, how they use them and how their internal models about digital learning materials change. Additional information about influences from the school environment, individual and collective learning by teachers when they develop a new approach of teaching and leadership practice is also collected. Through pattern matching three patterns are found that answer the research question. The overall conclusion is that the coherence between these factors determines whether an innovation will succeed or fail. This is an important new insight for both researchers and educational school leaders. It is obvious that interpersonal relationships are crucial. In line with social-constructivist ideas about learning, the research study confirms that educational changes are sustainable as the majority of teachers are gradually changing their ideas about good teaching in accordance with the strategic goals of the school and act upon it in the classroom. This is enhanced when colleagues together shape the idea of the innovation while working and constantly learning together. It seems of great importance that working on the innovation is organized as a joint task and that through this the exchange of experiences and collective reflection and sensemaking are facilitated. It is essential that supervisors create conditions for collective learning and participate actively in this process. In schools with such a learning culture school leaders operate asa learning community in both vertical and horizontal work relationships. The core of the leadership practice is a collective vision about educating students and at the same time it is alsoa vision about encouraging collective learning processes among professionals. Strategic leaders in these schools develop the strategic policy for the school which should be consistent with the learning ability of the staff and the teachers. This research leads to a conceptual model in which organizational learning, distributed leadership and context management are integrated. Recommendations for further research and rethinking strategies for educational improvement are formulated

Transposition, insertion, deletion and recombination drive variability in the type 3 secretome of pseudomonas syringae pv. Actinidiae, the transition from global effector comparisons to kiwifruit resistance breeding strategies

A strain of Pseudomonas syringae pv. actinidiae (Psa) that is particularly virulent (Psa-V or biovar 3) is responsible for the recent devastating global outbreak of bacterial canker on kiwifruit vines. We have now sequenced the genomes of over 30 isolates of Psa from around the world including two genomes (Psa-V and the type strain) to near completion. This extensive resource of genomic information has allowed us to reveal the remarkable plasticity exhibited by this pathogen and trace its evolution from the first geographically limited outbreaks on commercial kiwifruit production in the 1980s to the present global outbreak. We present examples of how this plasticity is driven by several different mechanisms including transposition, insertions/deletions and genome level recombination events and has resulted in at least four major phylogenetically defined groupings of Psa strains. These mechanisms have scrambled long distance co-linearity between even the most closely related of these phylogenetic groups, underlining the pace of genome-wide evolution in P. syringae pathovars. We focus on the impact of these events on the effector complement of the four main groupings of Psa strains in particular. As the loss of host resistance is typically linked with loss of these effectors we discuss how this knowledge is now being used to inform the long-term resistance breeding strategies being developed against this very damaging pathogen