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  • 1.
    Andersson-Gunnerås, Sara
    et al.
    Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå.
    Hellgren, Jenny M
    Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå.
    Björklund, Simon
    Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå.
    Regan, Sharon
    Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå.
    Moritz, Thomas
    Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå.
    Sundberg, Björn
    Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå.
    Asymmetric expression of a poplar ACC oxidase controls ethylene production during gravitational induction of tension wood2003In: The Plant Journal, ISSN 0960-7412, E-ISSN 1365-313X, Vol. 34, no 3, p. 339-349Article in journal (Refereed)
    Abstract [en]

    Ethylene is produced in wood-forming tissues, and when applied exogenously, it has been shown to cause profound effects on the pattern and rate of wood development. However, the molecular regulation of ethylene biosynthesis during wood formation is poorly understood. We have characterised an abundant 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase gene (PttACO1) in the wood-forming tissues of Populus tremula (L.) × P. tremuloides (Michx). PttACO1 is primarily expressed in developing secondary xylem, and is specifically upregulated during secondary wall formation. Nevertheless, according to GC–MS analysis combined with tangential cryosectioning, the distribution of ACC was found to be fairly uniform across the cambial-region tissues. Gravitational stimulation, which causes tension wood to form on the upper side of the stem, resulted in a strong induction of PttACO1 expression and ACC oxidase activity in the tension wood-forming tissues. The ACC levels increased in parallel to the PttACO1 expression. However, the increase on the upper (tension wood) side was only minor, whereas large amounts of both ACC and its hydrolysable conjugates accumulated on the lower (opposite) side of the stem. This suggests that the relatively low level of ACC on the tension wood side is a result of its conversion to ethylene by the highly upregulated PttACO1, and the concurrent accumulation of ACC on the opposite side of the wood is because of the low PttACO1 levels. We conclude that PttACO1 and ACC oxidase activity, but not ACC availability, are important in the control of the asymmetric ethylene production within the poplar stem when tension wood is induced by gravitational stimulation.

  • 2.
    Hellgren, Jenny
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Authentic science in the classroom—how scientific are students’ experiences?Manuscript (preprint) (Other academic)
    Abstract [en]

    This study aims to understand how students experience taking part in an authentic research project that aimed to increase motivation for science and understanding of research. It also aims to evaluate how these experiences are related to the science content and scientific way of working introduced in the authentic research project. Twenty-four students from three Swedish lower-secondary schools were interviewed. These students were selected to provide variation in motivation for school science. Analysis of the interviews shows that most students enjoyed taking part in the project, and that students referred mainly to reasons connected to science education; the authentic nature of the task, the hands-on and inquiry-based approach, and the opportunity to learn science. It further shows that even though the three teachers had different approach and the students were selected to get largest possible variation in motivation for school science, there were few differences in students’ experiences.

  • 3.
    Hellgren, Jenny
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Motivational variations when implementing a student-teacher-scientist partnership in the science classroomManuscript (preprint) (Other academic)
    Abstract [en]

    Authentic projects, where students meet, visit or work as scientists, are getting more common in schools. Little is known about the implementation of such projects and what effect the implementation has on students’ experiences and outcomes. This paper presents a study of twelve students in three classes that participate in same student-teacher-scientist partnership (STSP) in their Swedish secondary-science classrooms. The study includes three levels: the resources the teachers have, the opportunities for motivation through competence, autonomy and relatedness students are given, and students’ initiatives, group work and outcomes. The purpose of this study is to explore the process with which an authentic project is implemented in the science classroom and how the implementation can contribute to student motivation. The results show that all teachers spend the main part of lesson time with student-centred activities and that they all give opportunities for feelings of competence, autonomy and relatedness, but that they do it to different extent. Most students take initiatives towards science and/or procedure, have good dynamics of group work and have good outcomes. No clear patterns between students’ contextual motivation and their initiatives, group work or outcomes were seen, however, students in classrooms with high support were more able to overcome issues and succeed with the task. It can be concluded that the implementation is a key step when introducing authentic science in school and that it is both possible and advisable to design authentic science activities that can be part of the curriculum and reach a broad group of students. However, a good balance between novelty in topic and methods -through for example autonomy- and support, -through for example clear instructions and procedural support- should be a key component in the implementation, especially to support less self-regulated students. Implications for STSPs and similar authentic projects, as well as for other classroom situations, are discussed. 

  • 4.
    Hellgren, Jenny M
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Student Affective Experiences of an Authentic Research Project2014Conference paper (Refereed)
  • 5.
    Hellgren, Jenny M.
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Using theoretical and methodological triangulation to study motivation in the science classroom2019In: Bridging Research and Practice in Science Education / [ed] McLoughlin, E., Finlayson, O.E., Erduran, S., Childs, P., Springer, 2019, p. 107-122Chapter in book (Refereed)
    Abstract [en]

    Motivation cannot be measured directly but has to be evaluated through other indirect measurements, of which questionnaires are the most common. This chapter presents results from development and use of a model to approach motivation in the science classroom from multiple theoretical and methodological perspectives. The model emerged from the Hierarchical model of intrinsic and extrinsic motivation by Vallerand and the process model of motivation by Dörnyei. The chapter focuses on the relationship between students’ motivation, engagement and experiences when performing a novel science task. Results suggests that the students in two of the classrooms were better able to overcome challenges and complete the task than students in the third classroom. Further, no patterns were found between students’ contextual motivation and their actions or experiences. The multi-perspective model was a useful tool to align motivation as measured with questionnaires with motivation as seen through students’ actions in the classroom. The results show that more research on motivation from a situational perspective is needed, thereby we can learn more about relationships between motivation and actions, and between what happens in classroom and students’ long-term motivation for science. This knowledge has potential to lead to improved practices in science teaching.

  • 6.
    Hellgren, Jenny M
    et al.
    Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences.
    Olofsson, Kjell
    Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences.
    Sundberg, Björn
    Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences.
    Patterns of Auxin Distribution during Gravitational Induction of Reaction Wood in Poplar and Pine2004In: Plant Physiology, ISSN 0032-0889, E-ISSN 1532-2548, Vol. 135, no 1, p. 212-220Article in journal (Refereed)
    Abstract [en]

    Gravistimulation of tree stems affects wood development by unilaterally inducing wood with modified properties, called reaction wood. Commonly, it also stimulates cambial growth on the reaction wood side. Numerous experiments involving applications of indole-3-acetic acid (IAA) or IAA-transport inhibitors have suggested that reaction wood is induced by a redistribution of IAA around the stem. However, in planta proof for this model is lacking. Therefore, we have mapped endogenous IAA distribution across the cambial region tissues in both aspen (Populus tremula, denoted poplar) and Scots pine (Pinus sylvestris) trees forming reaction wood, using tangential cryosectioning combined with sensitive gas chromatography-mass spectrometry analysis. Moreover, we have documented the kinetics of IAA during reaction wood induction in these species. Our analysis of endogenous IAA demonstrates that reaction wood is formed without any obvious alterations in IAA balance. This is in contrast to gravitropic responses in roots and shoots where a redistribution of IAA has been documented. It is also of interest that cambial growth on the tension wood side was stimulated without an increase in IAA. Taken together, our results suggest a role for signals other than IAA in the reaction wood response, or that the gravitational stimulus interacts with the IAA signal transduction pathway.

  • 7.
    Hellgren, Jenny M
    et al.
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Stewart, Kirsty
    Sullivan, Kirk PH
    Umeå University, Faculty of Arts, Department of language studies.
    Student Experiences of Geocaching: Exploring Possibilities for Science Education2014Conference paper (Refereed)
  • 8.
    Hellgren, Jenny Maria
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Authentic science in the classroom: students’ perceptions of their experiences2019In: NorDiNa: Nordic Studies in Science Education, ISSN 1504-4556, E-ISSN 1894-1257, Vol. 15, no 3, p. 299-312Article in journal (Refereed)
    Abstract [en]

    The purpose of this study is to characterize how students experience taking part in authentic research, specifically through the Medicine Hunt, a project designed to increase motivation for science and under-standing of research in the Swedish secondary school. The study also investigates potential differences in students’ experiences related to context, in terms of participating in the Medicine Hunt in different class-rooms. Twenty-four students from three Swedish lower-secondary schools participating in the Medicine Hunt were interviewed. The main result is that students’ experiences were positive and related to science. Their focus is to a large extent on authentic science, and covers many of the aspects the Medicine Hunt is aiming to introduce in school, like the hands-on and inquiry-based ways of working and the opportunity to do what scientists do. Students’ answers are also to a high degree connected to the science content and to learning science. Few differences in students’ experiences related to the different classrooms were found.

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  • 9.
    Hellgren, Jenny Maria
    SLU.
    Ethylene and Auxin in the Control of Wood Formation2003Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis considers aspects of the regulation of growth rate and fibre properties in forest trees. These properties are both genetically determined and influenced by environmental stimuli. Induction of reaction wood is an environmentally induced process involving changes in growth rate and fibre properties that can be readily studied. Plant hormones are signalling agents that play important roles in the initiation and coordination of wood formation; in this thesis the plant hormones auxin and ethylene were investigated using gas chromatography/mass spectrometry (GC/MS). A novel MS technique for measuring the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) in minute amounts of plant tissue was developed. Ethylene is often connected to stress responses in plants, and ethylene evolution is increased when reaction wood is formed. Here it is demonstrated that this increase is regulated by ACC oxidase, the enzyme catalysing the last step in the ethylene biosynthetic pathway. This is in contrast to most of the earlier findings that tended to indicate that ethylene production directly reflects the availability of ACC. Although ethylene is strongly up-regulated during reaction wood formation, its role in modulating the growth rate and fibre properties remains unknown. Further, it is demonstrated that reaction wood in both poplar (Populus tremula L.) and pine (Pinus sylvestris L.) is formed without changes in auxin concentration in the cambial tissues. This suggests that the previously held assumption that the difference in auxin concentration is key factor in the induction of reaction wood is unsound. Further, auxin concentrations were compared in hybrid aspen trees (Populus tremula L. x tremuloides Michx.) growing vertically at different growth rates. These trees showed good correlations between auxin levels and growth rates. The growth rate was mediated by increases in the cell cycling rate rather than in the width of the cell division zone. Thus, the growth rate in poplar was correlated to auxin levels in normal wood formation, but not during reaction wood formation.

  • 10.
    Hellgren, Jenny Maria
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Students as scientists: a study of motivation in the science classroom2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    School science and mathematics have been criticized for being difficult, de-contextualised and teacher-centred. This thesis concerns student motivation in science and mathematics in secondary school, and in particular student motivation in relation to student-teacher-scientist partnerships (STSPs) and an authentic science task called the Medicine Hunt where students help scientists to find new antibiotics. The purpose of this dissertation is to interrogate the importance of authentic tasks for motivation in the science classroom. The thesis takes a starting point in motivation theories, with self-determination theory (SDT) in focus, and also builds on the hierarchical model of intrinsic and extrinsic motivation (HMIEM). A mixed-methods approach is used first, to find out what factors are important for students’ positive emotions and experiences in the classroom, and second, to learn more about the importance of authentic tasks using student interviews and observations in combination with questionnaires that evaluate students’ motivation. The studies reveal that the notion of having learnt something and intrinsic motivation are central for students’ positive emotions. Further, many situational factors, such as teacher support, autonomy, clear goals, and novelty of the task are central for both positive emotions and experiences in science and mathematics. Regarding the Medicine Hunt, students were positive and referred most of their positive experiences to science-related aspects, and the novelty of authentic science. Teachers gave different opportunities for competence, autonomy or relatedness when implementing the project in their classrooms, and these differences were more important for students’ initiatives and outcomes than students’ initial contextual motivation for school science. Students’ contextual motivation for science can change and the Medicine Hunt arrested the well-documented decline in students’ intrinsic motivation for science during the secondary school years. This thesis argues that authentic tasks implemented as STSPs such as the Medicine Hunt can contribute considerably to school science by providing motivating situations that channel students’ positive emotions and positive experiences, and that is possible to create authentic science learning situations in which both more and less motivated students can flourish. The findings highlight the teachers’ role in supporting the students’ process of extending their understanding of what science can include and in supporting students’ confidence as they adopt a broader and more authentic view of science when learning as part of a successful authentic STSP science project. The findings also suggest that more research focussing on motivation in different authentic situations, and how students’ experiences of authentic science can affect motivation in the longer term, is needed.

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  • 11.
    Palm, Torulf
    et al.
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education. Umeå University, Faculty of Science and Technology, Umeå Mathematics Education Research Centre (UMERC).
    Sullivan Hellgren, Jenny
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Winberg, Mikael
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Elevers motivation i matematik2010Report (Other academic)
  • 12.
    Sullivan Hellgren, Jenny
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education. Umeå University.
    Implementation of a student-teacher scientist partnership in the science classroom2015Conference paper (Refereed)
    Abstract [en]

    This paper examines the implementation of a student-teacher scientist partnership (STSP), focusing on the opportunities given to the students in the classrooms. The project in the study, the medicine hunt, aims to increase secondary-school students’ interest in science and understanding of research through authentic science problems, methods, and collaboration with researchers. The medicine hunt engaged 388 students in 18 school classes across Sweden. Video- and audio-recordings from one lesson in three different classrooms were analysed for i) how materials, class size and use of lesson time differ between the classrooms ii) what opportunities (i.e. learn scientific ways of working, inquiry, theoretical discussion and collaboration with researchers) are given to students in the different classrooms iii) differences in students’ attention and participation during the lesson. The variation in lesson time and number of students gave each teacher different possibilities to implement the STSP and variation in how the STSP was implemented was found. This is especially evident in the teachers’ foci in their introductions, and in the opportunities to engage in theoretical discussions. Despite differences, student engagement in terms of attention and participation was high in all classrooms throughout the lesson. Students in all classrooms practiced scientific ways of working (e.g. to select, describe and compare bacterial colonies, and to report findings) and took advantage of the collaboration with the researcher. Yet, opportunities for inquiry and theoretical discussion were low. The results suggest that it is important that teachers have sufficient content knowledge and enough time to engage in discussions with students to a deeper level than answering practical questions. How this links with the STSP implementation variation, engagement and participation will be considered.

  • 13.
    Sullivan Hellgren, Jenny
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Studying motivation in the science classroom2016In: Narratives of doctoral studies in science education: making the transition from educational practitioner to researcher / [ed] Shirley Simon, Christina Ottander, and Ilka Parchmann, Routledge, 2016, p. 56-67Chapter in book (Refereed)
    Abstract [en]

    I started my PhD with a theoretical approach that I increasingly had issues with. This chapter describes my search for a successful theoretical approach to motivation in the science classroom as a practitioner-researcher. I describe what problems I encountered and how these allowed me to narrow down my initial questions to those of greater relevance from a teacher- and classroom perspective. The chapter concludes with the new direction I chose for researching motivation in the science classroom during the second half of my PhD studies.

  • 14.
    Sullivan Hellgren, Jenny
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Towards a theoretical model for approaching motivation in the science classroom2017Conference paper (Refereed)
  • 15.
    Sullivan Hellgren, Jenny
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Using theoretical and methodological triangulation to study motivation in the science classroom2017Conference paper (Refereed)
  • 16.
    Sullivan Hellgren, Jenny
    et al.
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education. Umeå University, Faculty of Science and Technology, Umeå Mathematics Education Research Centre (UMERC).
    Bergqvist, Ewa
    Umeå University, Faculty of Science and Technology, Umeå Mathematics Education Research Centre (UMERC). Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Österholm, Magnus
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education. Umeå University, Faculty of Science and Technology, Umeå Mathematics Education Research Centre (UMERC).
    Argumentation in university textbooks: comparing biology, chemistry and mathematics2017Conference paper (Refereed)
  • 17.
    Sullivan Hellgren, Jenny
    et al.
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Lindberg, Stina
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Motivating students with authentic science experiences: changes in motivation for school science2017In: Research in Science & Technological Education, ISSN 0263-5143, E-ISSN 1470-1138, Vol. 35, no 4, p. 409-426Article in journal (Refereed)
    Abstract [en]

    Background: Students' motivation for science declines over the early teenage years, and students often find school science difficult and irrelevant to their everyday lives. This paper asks whether creating opportunities to connect school science to authentic science can have positive effects on student motivation.

    Purpose: To understand how authentic science experiences can affect students' motivation for science and students’ goals, values, beliefs and attitudes towards science.

    Programme description: The Medicine Hunt brought scientists and students together to find bacteria that produce secondary metabolites with antibiotic effects. Scientists received help with collecting soil samples and teachers and students took an active role in research and worked with solving an authentic problem as a part of their ordinary school science over a course of six months.

    Sample: About 388 students from 18 lower-secondary school classes participating in the Medicine Hunt. Students were enrolled in grade seven to nine (13–15 years old). At this stage, science is compulsory, and all students follow the same science course. The classes represented different geographical regions of Sweden.

    Design and methods: Students filled in motivation questionnaires before and after the Medicine Hunt. Paired t-tests were used to evaluate how students’ intrinsic motivation, goals, values, beliefs and attitudes towards science changed over the project period.

    Results: Students' intrinsic motivation for school science and plans for future participation in science remained unchanged during the period they participated in the Medicine Hunt, and students' goals, values and attitudes followed the well-documented pattern of decline. Thus, the authentic experience can arrest the well-described decline for some motivation-related factors.

    Conclusions: The findings suggest that the authentic experience can arrest some aspects of the decline in motivation for science in the teenage years. The paper discusses the processes around students' motivation in relation to authentic experiences.

  • 18.
    Sullivan, Kirk P H
    et al.
    Umeå University, Faculty of Arts, Department of language studies.
    Czigler, Peter E.Örebro University.Sullivan Hellgren, Jenny MUmeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Cases on Professional Distance Education Degree Programs and Practices: Successes, Challenges, and Issues2013Collection (editor) (Refereed)
    Abstract [en]

    Although internet technologies have transformed the concept of professional development by providing the opportunity for virtual learning environments in a non-traditional setting, the implementation of professional distance education programs still poses a challenge.

    Cases on Professional Distance Education Degree Programs and Practices: Successes, Challenges, and Issues examines the best practices for executing technology applications and the utilization of distance education techniques. This publication will serve as a reference for academics and instructors coordinating distance education programs, initiating distance education courses, and implementing such programs for those earning professional degrees.

  • 19.
    Winberg, Mikael T.
    et al.
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Hellgren, Jenny M.
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Palm, Torulf
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Stimulating positive emotional experiences in mathematics learning: influence of situational and personal factors2014In: European Journal of Psychology of Education, ISSN 0256-2928, E-ISSN 1878-5174, Vol. 29, no 4, p. 673-691Article in journal (Refereed)
    Abstract [en]

    The study aims to assess the relative importance of a large number of variables for predicting students’ positive-activating emotions during mathematics learning. Participants were 668 first-year upper secondary school students from 33 schools of different sizes and locations. Two questionnaires were distributed, one assessing students’ perceptions and beliefs about their learning situation in mathematics in general, and the other assessing the characteristics of a particular mathematics lesson and the students’ emotional experiences during this lesson. Single-construct and multivariate models for predicting students’ emotions were computed. The results show that the multivariate models were the most efficient, predicting as much as 59 % of the variance in students’ emotional experiences. The two most important constructs were students’ type of motivation and perceived degree of learning, which together predicted 48 % of the students’ emotions. Single-construct models predicted, at most, 36 %. The relative and absolute predictive ability of different motivational constructs are reported. The relationships between constructs and their implications for teaching are discussed.

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