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1.
Peter Reason 《Anthropology & education quarterly》2004,35(2):269-276
"Critical Design Ethnography: Designing for Change" is reviewed in terms of action research under five dimensions: knowledge in practice, participation and democracy, many ways of knowing, emergence, and worthwhile purposes. Particular attention is paid to the tensions between the design agenda and the empowerment agenda. 相似文献
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Eva Stratilov Martin apka Lubomí ra Rexov -Benkov 《Biocatalysis and Biotransformation》1989,2(4):317-326
Endopolygalacturonase (E.C. 3.2.1.15) was covalently bound to silica supports of different porosity treated with 3-(2',3'-epoxypropoxy)propyltrimethoxysilane. The activity and action pattern on sodium pectate and tetra(D-galactosiduronic acid) were investigated in batch and continuous flow-reactors. Pore size of the supports affected the loading of the enzyme as well as its action pattern and kinetics. A decrease in randomness of degradation of D-galacturonan, loss of specificity of (3 + 1) splitting of tetra(D-galactosiduronic acid) and decrease in Km value were found with the supports containing predominantly micropores. The extent of the changes decreased with increasing pore size of the support. The catalytic behaviour of endopolygalacturonase bound on the supports with large pores was quite analogous to that of the free enzymes. 相似文献
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《Biocatalysis and Biotransformation》2013,31(4):317-326
Endopolygalacturonase (E.C. 3.2.1.15) was covalently bound to silica supports of different porosity treated with 3-(2′,3′-epoxypropoxy)propyltrimethoxysilane. The activity and action pattern on sodium pectate and tetra(D-galactosiduronic acid) were investigated in batch and continuous flow-reactors. Pore size of the supports affected the loading of the enzyme as well as its action pattern and kinetics. A decrease in randomness of degradation of D-galacturonan, loss of specificity of (3 + 1) splitting of tetra(D-galactosiduronic acid) and decrease in Km value were found with the supports containing predominantly micropores. The extent of the changes decreased with increasing pore size of the support. The catalytic behaviour of endopolygalacturonase bound on the supports with large pores was quite analogous to that of the free enzymes. 相似文献
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Transdisciplinary education on sustainability for health has been primarily developed in high-income countries, yet the need in countries with limited research and human resource investments remains urgent. Little empiric documentation of the facilitators and barriers to transdisciplinary learning in such countries has been described. We assessed transdisciplinary learning among students of different disciplines collaborating with an Ecuadorian sustainability for health research project. Six undergraduate students from four different disciplinary backgrounds were incorporated through work–study agreements with provincial university academic supervisors. Learning was fostered and monitored through participant observations by a field supervisor. Students’ learning was evaluated through subsequent in-depth interviews and visualization methods. Academic supervisor key informant and co-investigator observations aided triangulation. Qualitative data were analyzed using indicators of transdisciplinary thinking. Principal factors facilitating transdisciplinary learning were interaction with social actors, the integration of work with other disciplines, the use of alternative research techniques and methods, and the constant support of the field supervisor. Inhibiting factors included the existence of rigid academic rules, lack of training of the academic supervisors in diverse research methods, and social pressures to implement unidisciplinary foci. At the end of their link with the project, students had developed both cognitive outcomes and attitudinal values relevant to sustainable development for health. In countries with limited investments in research and human resources development, transdisciplinary approaches with social actors and engaged researchers can sensitize new professionals training in traditional academic contexts to the ecological–social–health problems faced by poor majorities and encourage their subsequent work on sustainability for human health. 相似文献
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Loss or "gain" of function mutations in voltage-gated ion channels often results in an adverse neurological phenotype. We have examined the electrical characteristics of hippocampal pyramidal cells in a transgenic mouse model to determine how overexpression of a Shaker-type potassium channel subunit during early postnatal development might alter excitability properties of developing neurons. We found that in CA3 neurons potassium channel overexpression led to a transient shortening in duration of single action potentials during the first two postnatal weeks. There was an increase in maximal repolarization rate, without significant effect on the rate of rise. Transgenic CA3 neurons also showed a decrease of firing frequency in response to sustained depolarizing current injection. In contrast, repolarization of action potentials in CA1 neurons was not significantly altered by trangene expression. Western Blot Analysis of membrane-associated transgene protein indicated that transgene protein levels decreased during development, in agreement with functional measures of spike width. Our data indicate that the functional consequences of potassium channel transgene expression are dependent on cellular environment and developmental stage. A transient period of hypoexcitability during a critical period of development for CA3 neurons may contribute to the hyperexcitable phenotype observed in adult animals. 相似文献
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Daniel C. Johnson Ann Marie Stanley H. Ellie Falter Jennifer L. R. Greene Haley L. Moore Stacy A. Paparone 《Arts Education Policy Review》2013,114(4):208-220
AbstractThe purpose of this article is to make policy recommendations based on the authors’ experiences with, and research about, reflective, differentiated, and teacher-generated music teacher professional development (PD). By doing so, we argue for a bottom-up process that capitalizes on our music teacher and music teacher educator expertise along with the research literature in music teacher PD. We explore music teachers’ PD needs considering four career stages to explain how knowledge generated at each level informs our understanding of differentiated PD. From preservice music teachers and music teacher candidates, to in-service and veteran teachers, our discussion explores meaningful and effective ways to engage in deep, reflective thinking about the music teaching and learning process. Accordingly, we provide specific policy recommendations for music teachers at each career stage so that they might take greater ownership of their own learning, growth, and development through local, reflective, self-initiated, and differentiated PD opportunities. 相似文献
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Nathan Emery Amanda Hund Romi Burks Meghan Duffy Christine Scoffoni Andrea Swei 《Ecology and evolution》2019,9(8):4316-4326
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生物化学是研究活细胞及有机体内各种分子及其相互间化学反应的科学,即研究生命的分子基础。细胞是生物体的基本结构和功能单位,机体的众多化学反应都在细胞内进行,所以生物化学又被定义为研究活细胞的化学组成及相互反应和进程的科学,即“生命的化学”,其实它涉及了细胞生物学、分子生物学和分子遗传学等几个大的学科领域。所以,生化研究的策略和技术发展对生命科学研究特别重要。由于有关生物医学科学的相互渗透以及生化与分子生物学技术的飞速进展,近两个世纪内(1780-1970年)生物化学的发展历经了从叙述生化进入功能或分子生化的阶段。在不久的将来,许多生命科学的关键问题将在分子机制和基因水平的基础上获得解决。 相似文献
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Dora Goodrich M.A. 《Arts Education Policy Review》2013,114(2):79-99
Although much has been written about professional development in general education and music education literature, little has addressed the benefits of music-making as meaningful professional development for music teachers. For music teachers, music-making and meanings of music-making have been connected with teachers' identity, well-being, beliefs, and effectiveness, as well as being a powerful pedagogical tool and a way to develop presence in teaching. Presence in teaching is linked with self-awareness, attentiveness, and pedagogical knowledge. The purpose of this article is to explore the benefits of music-making for music teachers in order to convince policymakers of the value of music-making as a professional development activity for music teachers. This article explores theories from psychology and education that link engagement, well-being, and identity to lay the foundation for a justification of broadening professional development policies. Then, literature is presented that connects teachers' art-making experiences (past and present), identity, teaching, and student learning. The third section draws on my previous work to illustrate the intersections between teachers' music-making and teaching. Then, suggestions for implementing professional development programs with music-making components are made. Although there are many ways music-making could be included as professional development, I offer four suggestions: including music-making in departmental or district-wide meetings, granting professional development credit to music teachers who make music outside of the classroom, setting up in-classroom reflection opportunities/action research based on integrating music-making and music teaching, and initiating a collaborative teacher study group that includes chamber music collaboration. 相似文献
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Action potentials as multifunctional signals in plants: a unifying hypothesis to explain apparently disparate wound responses 总被引:9,自引:5,他引:9
E. DAVIES 《Plant, cell & environment》1987,10(8):623-631
Abstract I suggest that action potentials, which occur in most, if not all, plants, play a major role in intercellular and intracellular communication. Long-distance communication is achieved through the transmitted changes in membrane potential, whereas local signalling is achieved through changes in the subcellular localization of ions (K+, Cl?, and Ca2+) and of water, and perhaps by membrane depolarization and current flow. These local changes in ion concentration can lead to modified activities of enzymes in the cell wall (e.g. pectinase), the plasma membrane (e.g. cellulose synthetase, callose synthetase), and the cytoplasm (e.g. protein kinase). In particular, the elevated concentration of cytoplasmic Ca2+ is shown to have a major, yet complex, role, especially in the modulation of translation. I suggest further that, in addition to their role in wounding, action potentials may also be important signalling mechanisms for chilling injury, mechanical perturbation and invasion by pathogens, as well as for light and gravity. 相似文献
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The article analyzes professional development in music education considering the ways in which policy change depends on conditions where renewed practice can become self supporting. The authors situate professional development amid the current politico-educational climate while offering an interpretive framework based on key issues and actions identified by other authors in this issue of Arts Education Policy Review. Further, they suggest a pragmatic policy agenda focused on the notion of a strategic architecture for professional development in music education, arguing that it may bring (1) greater confidence in teacher's capacity to adapt, engender concepts, intervene in instructional patterns, and establish positive feedback loops; and (2) improvement in teacher retention and productivity. The article calls for a professional development agenda that sees teachers as capable change agents and that is jointly incentivized by union leaders, government, and institutions of higher learning. 相似文献
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ABSTRACTBiology education should be relevant to young students so that they can become interested in biology and understand biological topics in their everyday and vocational lives. We conducted interviews and collected mind maps to examine Finnish pre-service biology teachers’ (N = 16) views on the relevance of biology education. Furthermore, we analysed Finnish secondary school biology curricula, which were compared with the pre-service teachers’ answers. We classified the views on relevance into nine main categories using grounded theory as the methodological frame of reference. Pre-service teachers emphasised the relevance of biology to the student’s own life, whereas scientific practices and the nature of science were expressed in secondary school curricula more often. Novice pre-service teachers put more value on general knowledge, while more experienced pre-service teachers were more likely to mention sustainable futures and societal aspects in their reasoning. Based on the results, we identified two stages in the development of the views. This study suggests that pedagogical studies, teaching experience and teacher training have an impact on the pre-service teachers’ views about the relevance of biology education. Moreover, we could find differences between curricula and pre-service teachers’ views, especially regarding scientific practices and the role of the nature of science in biology education. 相似文献
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丹参酮是一类从传统中药材丹参中提取的醌类化合物,近年研究发现其具有多种生物活性,包括抗氧化,抗炎,抑制增殖,诱导凋亡等作用,本文针对丹参酮自2008年至今的国内外抗肿瘤研究进行综述。 相似文献
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目的:研究3至5岁儿童能否对主动行为、被动行为加以区分以及其控制能力的差异和两者是否相关。方法:设计两个任务:衡量儿童对主动与被动行为区分的意图实验与衡量儿童自我控制能力的七巧板任务。结果:意图实验年龄效应显著,F=48.317,P<0.001。七巧板任务年龄效应显著:F=88.123,P<0.001,意图实验与七巧板任务相关显著:r=0.79 t=8.37,P<0.01。结论:儿童对主动行为和被动行为的区分转折点为4岁;儿童的自我控制能力以坚持性为指标时转折点在4岁;儿童时意图行为的区分与自我控制能力具有相关性。 相似文献
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Giovanni Buccino 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2014,369(1644)
This review focuses on a novel rehabilitation approach known as action observation treatment (AOT). It is now a well-accepted notion in neurophysiology that the observation of actions performed by others activates in the perceiver the same neural structures responsible for the actual execution of those same actions. Areas endowed with this action observation–action execution matching mechanism are defined as the mirror neuron system. AOT exploits this neurophysiological mechanism for the recovery of motor impairment. During one typical session, patients observe a daily action and afterwards execute it in context. So far, this approach has been successfully applied in the rehabilitation of upper limb motor functions in chronic stroke patients, in motor recovery of Parkinson''s disease patients, including those presenting with freezing of gait, and in children with cerebral palsy. Interestingly, this approach also improved lower limb motor functions in post-surgical orthopaedic patients. AOT is well grounded in basic neuroscience, thus representing a valid model of translational medicine in the field of neurorehabilitation. Moreover, the results concerning its effectiveness have been collected in randomized controlled studies, thus being an example of evidence-based clinical practice. 相似文献
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丹参酮的药理作用研究进展 总被引:3,自引:1,他引:3
丹参酮在中药丹参中的含量较高,有较强的生理活性,是丹参主要有效成分之一。丹参酮的药理作用极其广泛,本文就丹参酮的抗肿瘤、抗动脉粥样硬化、抗心律失常、缩小心肌梗死面积、降低心肌耗氧量、逆转左心室肥厚、减轻缺血再灌注损伤、保肝脏及抗肝纤维化、保护心肌、改善微循环、抗菌消炎等作用进行综述,以便促进中药丹参在临床上广泛的应用。 相似文献
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蒺藜化学成分及其药理作用研究进展 总被引:32,自引:0,他引:32
蒺藜全草中含有皂甙、生物碱、黄酮、多糖、基氨酸等化学成分,其活性成分对动物及人体的心脑血管系统、中枢神经系统、性功能及肌肉体系等有一定程度的作用,为此就其化学成分及其相应药理研究进展作一综述。 相似文献
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This paper describes the amylolytic action pattern of Thermococcus hydrothermalis recombinant amylopullulanase (Th-ApuΔ2) [E.C 3.2.1.41]. A comparison was made between amylose hydrolysis catalyzed by this
enzyme and by two other amylolytic enzymes: α-amylase [E.C 3.2.1.1] (from Aspergillus oryzae) and glucoamylase [E.C. 3.2.1.3] (from Aspergillus niger), respectively taken as models for “endo” and “exo” catalytic patterns. Different independent physico-chemical methods were
used to characterize the hydrolysis products obtained with the studied enzymes. Viscosity results were correlated to reducing
sugars analysis to show a similarity between glucoamylase [E.C. 3.2.1.3] and Th-ApuΔ2 [E.C 3.2.1.41] behavior. On the other
hand, whereas α-amylase [E.C 3.2.1.1] action rapidly decreased the viscosity of medium, glucoamylase and Th-ApuΔ2 hydrolysates
have only shown a negligible reduction in viscosity. Glass transition temperatures of glucoamylase and Th-ApuΔ2 hydrolysates
were found comparable (225–226°C) and significantly different from that of α-amylase (197°C). Thin-layer chromatographic analysis
of hydrolysates mainly revealed the presence of glucose in the case of glucoamylase and Th-ApuΔ2 activities and in addition
to glucose the Th-ApuΔ2 chromatograms have shown oligosaccharides with polymerization degree ranging from 2 to 7. These results
incite us to conclude that Th-ApuΔ2 has a dual “endo” and “exo” catalytic action pattern. Analysis of the Fourier transform
infrared (FTIR) results shows a comparable general aspect for all spectra. The presence of more numerous differentiated and
intense peaks in the spectrum of Th-ApuΔ2 hydrolysate reveals the presence of short-chain oligosaccharides. These results
confirm thin-layer chromatography results and support a dual action pattern. 相似文献