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1.
The search for active toxins for managing weeds or plant diseases is believed to be a promising avenue of investigation. However, the effects of Alternaria toxins on insects have just begun to be investigated. Bioactivities of toxins from four strains of Alternaria alternata on Rosa chinensis and rose aphid Macrosiphum rosivorum were tested in the present study. At a concentration of 50.0 μg/ml, the crude extract (toxin) of strain 7484 was found not to be harmful to rose plants with excised leaf-puncture method (P≥0.079), and rose plants showed enhanced resistance to rose aphids when this Alternaria toxin was sprayed on the plants (P≤0.001). However, this toxin caused no detrimental effects on aphids in insecticidal bioassay at a concentration of 10.0 to 160.0 μg/ml (P≥0.096). Therefore, the Alternaria toxin had significantly induced the resistance of rose plants against rose aphids, demonstrating that the resistance mechanism triggered by the Alternaria toxin in the rose plant may also be used by the plant to defend itself against insects. Further bioassays aimed to discover the olfactory responses of aphids to the toxin-induced volatiles of host plants. The aphids were significantly more attracted to both volatiles emitted and collected from control rose plants than to both volatiles emitted and collected from the toxin-treated rose plants (P≤0.014). This result showed that the toxin-induced resistance related to the volatile changes of host plants.  相似文献   

2.
This paper argues that the conceptions of ‘space’ (and increasingly ‘time’) in the discussion of ‘the university’ (in its most transcendent sense) have gone through four distinct phases in the UK. Using a Heideggerian conception of ‘space’ where usefulness is more important than proximity, the ‘ancient’ universities were ‘useful’ to the gentry and thus were ‘closer’ to them than to the excluded ‘local’ poor in the institutions’ vicinities. The ‘civic’ universities on the other hand stressed ‘localism’ as part of their mandate – to educate the people of their locality (but only those of the new industrial middle class). The ‘Robbins’ universities were a partial return to the ‘ancient’ notion of learning as a ‘lived’ activity, providing scenic landscapes on green-belt campuses where students could ‘retreat’ from the ‘real world’ for the duration of their studies. The ‘spatial’ quality of these places was thus part of a conception of higher education as ‘lifestyle choice’ where young people moved away from their locality to study. As such ‘proximity’ was an issue only insofar as the greater the distance from one’s point of origin the better for successful immersion in the growing student ‘culture’. The ‘new/post-1992’ universities partially retained their polytechnic mandate to educate local people, but embraced a colonialist impulse regarding local space usage. ‘ ‘The discussion can be further refined to argue that these four stages are merely two phases which have repeated themselves: from ancient ‘exclusivity’ to civic ‘localism’ and back to Robbins era ‘exclusivity’ and thence to post-1992 ‘localism’ once more’. The opening up of higher education via the Internet in the late 20th and early 21st centuries provides for the possibility of the growth of entirely non-spatial and asynchronous learning experiences, and as such we may well be on the verge of the fifth stage of university development.  相似文献   

3.
Trust and improvement in schools   总被引：3，自引：1，他引：2  
This paper examines how trust affects teachers’ willingness to work with innovations introduced by central office administrators. Interview and focus group data collected over a three-year period in five schools are used to analyze the centrality of trust to teachers’ willingness to work with administrators to implement continuous improvement and quality management practices for their schools and classrooms. A qualitative data analysis software package was used to code interviews and focus groups for spontaneous comments that addressed trust. Two schools were characterized by high trust, and high willingness to change; high levels of distrust distinguished three others. This emphasis of the analysis is on the association of spontaneously expressed sentiments of trust or distrust and the association of those sentiments with willingness to participate in change initiated from outside the school building. Pre-existing patterns of relational and institutional trust will enhance or limit the ability of leaders to initiate large-scale change. More needs to be known about how to change coherently distrustful school settings in order for systemic change to occur.
Karen Seashore LouisEmail:
  相似文献   

4.
In a simultaneous discrimination involving a positive (S+) and a negative (S−) stimulus, positive value appears to transfer from the S+ to the S−. However, negative value does not appear to transfer from the S− to the S+. Instead, when sufficient experience with the contingencies associated with responding to the S− is provided, it appears that the presence of the S− enhances the value of the S+ (i.e., a contrast effect is found). The purpose of the present experiments was to further examine the influence of the S+ on the S− in a simultaneous discrimination (between subjects in Experiment 1 and within subjects in Experiment 2). In both experiments, we found that under typical training conditions, given little direct experience with the value of the S−, value transfers from the S+ to the S−. If sufficient experience with the value of the S− is provided, however, contrast between the S+ and the S− can be demonstrated. Thus, in a simultaneous discrimination, value transfer from the S+ to the S− depends on the animal’s having responded relatively little to the S−.  相似文献   

5.
Formative assessment is considered to be helpful in students' learning support and teaching design. Following Aufschnaiter's and Alonzo's framework, formative assessment practices of teachers can be subdivided into three practices: eliciting evidence, interpreting evidence and responding. Since students' conceptions are judged to be important for meaningful learning across disciplines, teachers are required to assess their students' conceptions. The focus of this article lies on the discussion of learning analytics for supporting the assessment of students' conceptions in class. The existing and potential contributions of learning analytics are discussed related to the named formative assessment framework in order to enhance the teachers' options to consider individual students' conceptions. We refer to findings from biology and computer science education on existing assessment tools and identify limitations and potentials with respect to the assessment of students' conceptions.

Practitioner notes

What is already known about this topic
  • Students' conceptions are considered to be important for learning processes, but interpreting evidence for learning with respect to students' conceptions is challenging for teachers.
  • Assessment tools have been developed in different educational domains for teaching practice.
  • Techniques from artificial intelligence and machine learning have been applied for automated assessment of specific aspects of learning.
What does the paper add
  • Findings on existing assessment tools from two educational domains are summarised and limitations with respect to assessment of students' conceptions are identified.
  • Relevent data that needs to be analysed for insights into students' conceptions is identified from an educational perspective.
  • Potential contributions of learning analytics to support the challenging task to elicit students' conceptions are discussed.
Implications for practice and/or policy
  • Learning analytics can enhance the eliciting of students' conceptions.
  • Based on the analysis of existing works, further exploration and developments of analysis techniques for unstructured text and multimodal data are desirable to support the eliciting of students' conceptions.
  相似文献   

6.
The achievement motive concept refers to a relatively stable personality characteristic in terms of a capacity to anticipate affects in achievement situations. The motive to achieve success (M s ) refers to the individual's capacity to anticipate positive affects, and the motive to avoid failure (M f ) refers to a capacity to anticipate negative affects in achievement situations. Based, among other things, on the conceptualizations of motives, a measurement was constructed to tap the two aspects (M s and M f ) of motivation. Over the years the scale has been translated to several languages and used in a number of studies. The Czech version of the scale is an adapted translation of the English one, and was administered to 179 pupils in the sixth grade in 1989. Further, the subjects were retested after an interval of 12 weeks. The analyses indicate that the psychometric properties of the Czech version of AMS are promising.  相似文献   

7.
Educational applications (apps) offer opportunities for designing learning activities children enjoy and benefit from. We redesigned a typical mobile learning activity to make it more enjoyable and useful for children. Relying on the technology acceptance model, we investigated whether and how implementing this activity in an app can increase children's intention to use. During the 27-day study, children (N = 103, 9–14 years) used the app to memorize one-sentence learning plans each day. Children used three different app-based learning activities throughout the study. In two standard activities, children reread or reassembled the words of the plan. In the redesigned activity, children represented the meaning of the plan with emojis. Children repeatedly reported on their attitude towards each activity. Subsequently, children reported perceived enjoyment and intention to use the app. Results showed children found the emoji activity most enjoyable, and enjoyment of the emoji activity contributed uniquely towards intention to use. Additionally, children's enjoyment of the app mediated their intention to use the app in the future. Overall, the study suggests that children's enjoyment of an app is crucial in predicting their subsequent intention to use, and it provides a concrete example of how emojis can be used to boost enjoyment.

Practitioner notes

What is already known about this topic
  • Educational applications provide children with unrestricted access to mobile learning resources.
  • Positive attitudes towards educational applications predict behavioural intention to use these applications, at least in young adults.
  • There is a need for more research examining the relevance of enjoyable learning activities in fostering children's sustained usage of an educational application.
What this paper adds
  • Positive attitude towards the use of emojis during learning activities uniquely contributed to children's behavioural intention to use the application.
  • Perceived enjoyment predicted behavioural intention to use the application.
  • Perceived enjoyment mediated the effect of attitude towards using learning activities on the behavioural intention to use the mobile educational application.
Implications for practice and/or policy
  • These findings highlight the importance of enjoyment for children's' acceptance of educational applications.
  • Enjoyable learning activities are necessary to ensure sustained usage of educational applications.
  • The paper provides a concrete example of how emojis can be used to boost enjoyment of a typical mobile learning activity.
  相似文献   

8.
This paper reports the findings of an investigation aimed at gaining a clearer understanding of the nature of vocabulary difficulties associated with dyslexia and associated risk status. Three studies were conducted to examine preschoolers’ access and mastery of syntactic- and phonological-based processes believed to support word learning. Results are reported for 82 participants whose (reading) risk status was assessed from a composite of measures known to be related to reading development. As expected, risk status correlated positively with participants’ ability to recall the phonological form of novel nouns. No relationship was found between risk status and participants’ use of syntactic form-class cues in interpreting the noun class of novel names in isolation. However, the ability to use form-class cues was impaired for at-risk participants on a task that required them to learn both the phonological form and noun class. Findings are discussed in relation to the suggestion that limitations in processing resources such as working memory rather than in the availability of language structures may be at the root of the reported poor performance by at-risk children on vocabulary and other linguistic measures.
Megan Louise GilliverEmail: Email:
  相似文献   

9.
Abstract

Recent literature on bullying suggests that victims of KEYW ORDS bullying are likely to have certain emotional reactions that contribute anti-bullying to the problem. This is not to say that victims in any way deserve the intervention; treatment that they get from more aggressive peers, but rather to bullying; propose that they themselves can be empowered to change the situ-bystanders; ation. The purpose of the present review is to examine the proposal emotional that the ways in which victims express their emotions during a bullying expression episode can play a crucial role in the responses of peers. There are implications for both researchers and practitioners to develop new insights that may help vulnerable children and adolescents.  相似文献   

10.
The term ‘concept’ is used in different ways within educational literature and has at least two different, although related, referents in relation to science knowledge, namely, public knowledge and private understandings. A taxonomic structure for ‘science concepts’ (public knowledge) has been developed to provide a rationale for the choice of phenomena to be used in the investigation of students’ ‘concepts’ and also to act as a frame of reference for generating insights about the data to be collected. Furthermore, it may be a useful heuristic to predict other science concepts likely to be highly problematic in school teaching situations and thus worthy of detailed research. The taxonomy, called a ‘Scale of Empirical Distance’ (SED), enables science concepts to be mapped according to their degree of closeness to concrete realities. The scale shows a recognition of the empirical basis of science concepts and the role of human senses in the perception of the material world even though “absolute objectivity of observation is not a possible ideal of science” as Harre (1972) has noted. The scale uses two binary variables, namely, ‘visual’ and ‘tactile’, to generate four categories of science concepts ranging on a continuum from concrete to abstract. Some concepts related to ‘matter’ will be classified and discussed. Specializations: science teacher education, primary science curriculum and methods, students’ personal meanings of phenomena.  相似文献   

11.
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12.
Using a global–local dialectic approach, this paper traces the rise of the basic education programme in the 1980s and 1990s in Botswana and its subsequent attenuation in the 2000s. Amongst the local forces that led to the rise of BEP were Botswana's political project of nation-building; the country's dire human resources situation in the decades following Independence in 1966; and its propitious economic climate in the late 1970s and early 1980s. Global forces included the global circulation of the World Bank's educational discourse on the primacy of primary education as a public ‘investment’ option and Botswana's desire to be a member of the influential transnational social structure. BEP's attenuation can similarly be traced back to both local and global forces. Local forces included the growth of youth unemployment, and a sluggish economy. Global forces included the globalization of neo-liberalism which called for cost-sharing/recovery measures, and, ironically, Botswana's ‘promotion’ to a ‘middle income status’ country. While conceptually the attenuation represents a case of policy reversal and in some ways a sense of ‘loss’, empirically, the attenuation has not been of material consequence to access to ‘basic’ education. This is attributed to the ambiguous position (best captured by the term ‘doublethink’) the Botswana government1 has adopted in relation to the issue of school fees.  相似文献   

13.
“走出去”已成为中国教育对外开放的重要方向。从战略构建的角度看,“中国教育走出去”亟须回应四个基本问题:其一,从传统中国的文化信仰,当代中国的现实利益以及可能产生的国际贡献中寻求“走出去”的重要意义;其二,界定作为抽象主体的国家与作为行动主体的政府、教育组织、企业、非政府组织所应扮演的角色;其三,在资源与知识的二元分类框架中理解“中国教育走出去”的内容载体,并推进其由硬投入向软影响转变;其四,充分利用有效的国际机制,拓展“中国教育走出去”的路径。  相似文献   

14.
Abstract

In many countries agriculture is in a process of rapid change,

  • - it has to meet a growing demand for food in a sustainable way,

  • - the international competition is increasing,

  • - the increase in labour productivity is decreasing the employment opportunities in agriculture,

  • - agricultural research is offering many new opportunities to increase productivity,

  • - government price support for agricultural products in industrial countries is decreasing.

These changes have many implications for agricultural extension, such as:

  • - the knowledge and capabilities of farmers has become a major factor in their ability to compete in national and international markets,

  • - advice is not only needed on the adoption of new technologies, but also on many other decisions farmers have to make, such as the choice of their farming system and the decision whether or not to earn an income from outside agriculture,

  • - this requires a change in extension methods and in the information sources extension agents use,

  • - agricultural development demands painful changes in the way of farming and of living for many farm families. It is a challenge for extension agencies to help farm families to realise this,

  • - a major task for leaders of extension organisations is to manage a process of change in agricultural extension. Often the role extension has to play in agricultural development can not be performed by one extension organisation, but only by a pluralistic extension system.

Agricultural extension is often expected to contribute to a reduction of poverty among farmers and farm labourers. One has to think seriously how one can realise this objective.  相似文献   

15.
The purpose of this paper is to examine the remnants of desegregation curricular reforms in a small urban district. This study documents the affects of various policies that were implemented to create equity and equality in urban, multi-racial and socio-economically diverse classrooms. These reforms were created due to a court desegregation order that demanded the district take multiple steps to raise the academic achievement levels of students of color in the district. Using the lens of Critical Race Theory to examine issues of interest-convergence and the effects of court-ordered desegregation initiatives, the researcher documents how teachers have come to terms with two major curricular changes that work in conjunction with other curricular reforms. Research that considers the affects of large-scale policy initiatives on classroom practices is necessary to further current conversations on successful reform implementation.
Thandeka K. ChapmanEmail:
  相似文献   

16.
This longitudinal study investigated the effect of experience with tactile stimulation on infants' ability to reach to targets on the body, an important adaptive skill. Infants were provided weekly tactile stimulation on eight body locations from 4 to 8 months of age (N = 11), comparing their ability to reach to the body to infants in a control group who did not receive stimulation (N = 10). Infants who received stimulation were more likely to successfully reach targets on the body than controls by 7 months of age. These findings indicate that tactile stimulation facilitates the development of reaching to the body by allowing infants to explore the sensorimotor correlations emerging from the stimulation.  相似文献   

17.
This paper provides a review of research that examines the development and expression of agency in and through high-school physics. The interchange offers realizations and questions brought to mind by the reading of the research and provides written comments connected to specific sections of the paper germane to my own theoretical perspective. Within the context of this commentary, raised issues are discussed in a dialogic manner in order to elucidate deeper understanding concerning the empirical investigation presented in the study. As a final point, a brief synopsis is put forward regarding some of the contributions that studies such as the one reviewed have to offer for providing equitable access to science for all students.
John M. RevelesEmail:
  相似文献   

18.
Following simultaneous discrimination training with pigeons, in which responding to the S−was reinforced on half of the trials and responding to the S− was never reinforced, we examined the effect on the S− of presenting the S− by itself and the effect on the S+ of presenting the S− by itself (relative to an S− or an S− for which there had been no single-stimulus presentations). For Group A−, responding to the S− presented by itself was always reinforced, whereas for Group A−, such responding was extinguished. For Group B−, responding to the S− presented by itself was always reinforced, whereas for Group B+, responding was extinguished. Although both Group A+ and Group A−tended to avoid their associated S− (relative to a control S−), Group A+ avoided its associated S− less than did Group A−. In contrast, although for Group B−, presentation of the S− alone increased the pigeons’ preference for its associated S−(relative to a control S+), for Group B−, presentation of the S−alone had little effect on its preference for its associated S+. These results suggest that presentation of one stimulus from a simultaneous discrimination has two independent and sometimes opposite effects on the other discriminative stimulus. First, it reduces the strength of within-event conditioning between the S+ and the S−, and second, if the value of the singly presented stimulus has increased, some of its newly acquired value will transfer retroactively to the stimulus with which it was originally paired.  相似文献   

19.
The significance of e-Learning and knowledge management at the workplace cannot be overemphasized. With the rapid change in all types of working environments, especially medical and healthcare environments, there is a constant need to rapidly train and retrain people in new technologies, products, and services found within the environment. There is also a constant and unrelenting need for appropriate management and leveraging of the knowledge base so that it is readily available and accessible to all stakeholders within the workplace environment. In addition, within the medical and healthcare setting, certain other factors reinforce this need for constant refreshing, training, and retraining of its workers. These factors are outlined below:
• Heightened expectations for improved quality of healthcare services from an increasingly aware and empowered public,
• Acute shortage of doctors and other healthcare professionals (requiring “multitasking” efforts from individuals and thus “forced” learning of new skill sets),
• Heterogeneous standards of healthcare as practised by medical practitioners necessitating policies designed to audit and streamline medical and healthcare practices as per enforcement of minimal credit points to be tied up to issuance/renewal of annual practicing certificates (APC),
• Increased complexity of healthcare services, technologies and products, and,
• Accelerated technological changes.
Our TeleHealth Initiative intends to implement this integration into the healthcare setting workplace via the following applications, namely:
• Just-in-time Continuing Medical Education (CME), which refers to significant and relevant information that can value-add to patient management at the appropriate time and appropriate segment of encounter,
• Formal Distant Education (FDE), which refers to electronic courses delivered online resulting in award of certificates conferred by accredited academic institutions or agencies,
• Modular Distance Learning (MDL), which refers to packaged learning modules designed to maintain competencies and to excel at relevant knowledge and skills which are tied in to issuance/renewal of practising licenses of the healthcare professionals, and,
• Personalised CME, which refers to knowledge, information, and skill sets pushed to healthcare professionals tailored to their areas of expertise, interest, and need.
The solutions as outlined above will be delivered via Internet-based content accredited by relevant authorities. This paper describes our mission to integrate e-Learning into health-related settings and into the routine daily life of medical and healthcare professionals.  相似文献   

20.
Abstract

This paper reassesses the value of the popular Greek concept of being a sistimatikos person to face rural development challenges. It dwells on fieldwork with olive growers in Western Crete, where a study was carried out to appraise the socio-economic and ecological impact on regional development of organic olive oil production. Working sistimatika turned out to be essential for organic farmers to develop their enterprise. This notion comprises knowledge about what to do, which is made up of a clear vision and technical knowledge about how to organize the work, hard work, love, and finally an ability and desire to search for and learn whatever may be needed. The aspects love and learning capacity are usually unacknowledged in Western conceptions of development strategies informed by a so-called systems approach, but are, however, essential to arrive at what is headed for: specifically, in the Cretan case, the production of organic olive oil, and in general, the conceptualization and materialization of development alternatives for rural areas.  相似文献   

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