| 1. |
- Ackley, K., et al.
(author)
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Observational constraints on the optical and near-infrared emission from the neutron star-black hole binary merger candidate S190814bv
- 2020
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In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 643
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Journal article (peer-reviewed)abstract
- Context. Gravitational wave (GW) astronomy has rapidly reached maturity, becoming a fundamental observing window for modern astrophysics. The coalescences of a few tens of black hole (BH) binaries have been detected, while the number of events possibly including a neutron star (NS) is still limited to a few. On 2019 August 14, the LIGO and Virgo interferometers detected a high-significance event labelled S190814bv. A preliminary analysis of the GW data suggests that the event was likely due to the merger of a compact binary system formed by a BH and a NS.Aims. In this paper, we present our extensive search campaign aimed at uncovering the potential optical and near infrared electromagnetic counterpart of S190814bv. We found no convincing electromagnetic counterpart in our data. We therefore use our non-detection to place limits on the properties of the putative outflows that could have been produced by the binary during and after the merger.Methods. Thanks to the three-detector observation of S190814bv, and given the characteristics of the signal, the LIGO and Virgo Collaborations delivered a relatively narrow localisation in low latency - a 50% (90%) credible area of 5 deg(2) (23 deg(2)) - despite the relatively large distance of 26752 Mpc. ElectromagNetic counterparts of GRAvitational wave sources at the VEry Large Telescope collaboration members carried out an intensive multi-epoch, multi-instrument observational campaign to identify the possible optical and near infrared counterpart of the event. In addition, the ATLAS, GOTO, GRAWITA-VST, Pan-STARRS, and VINROUGE projects also carried out a search on this event. In this paper, we describe the combined observational campaign of these groups.Results. Our observations allow us to place limits on the presence of any counterpart and discuss the implications for the kilonova (KN), which was possibly generated by this NS-BH merger, and for the strategy of future searches. The typical depth of our wide-field observations, which cover most of the projected sky localisation probability (up to 99.8%, depending on the night and filter considered), is r similar to 22 (resp. K similar to 21) in the optical (resp. near infrared). We reach deeper limits in a subset of our galaxy-targeted observations, which cover a total similar to 50% of the galaxy-mass-weighted localisation probability. Altogether, our observations allow us to exclude a KN with large ejecta mass M greater than or similar to 0.1 M-circle dot to a high (> 90%) confidence, and we can exclude much smaller masses in a sub-sample of our observations. This disfavours the tidal disruption of the neutron star during the merger.Conclusions. Despite the sensitive instruments involved in the campaign, given the distance of S190814bv, we could not reach sufficiently deep limits to constrain a KN comparable in luminosity to AT 2017gfo on a large fraction of the localisation probability. This suggests that future (likely common) events at a few hundred megaparsecs will be detected only by large facilities with both a high sensitivity and large field of view. Galaxy-targeted observations can reach the needed depth over a relevant portion of the localisation probability with a smaller investment of resources, but the number of galaxies to be targeted in order to get a fairly complete coverage is large, even in the case of a localisation as good as that of this event.
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| 2. |
- Bruun, Jesper, et al.
(author)
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Mystronics Class
- 2015
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Other publication (pop. science, debate, etc.)abstract
- It’s the schools year’s first lesson in Mystronics. All students are excited. Some have looked forward to this day, while others just need to complete the class to get onward in the system. Some dream of a career as mystronician.A new professor have been hired for the teaching, one with highly unorthodox teaching methods. The board of professors are naturally sceptic, but secretly many professors are curious and fascinated by the new methods.In this larp you will play student or teacher in the first Mystronics class of the year. The larp is based on research in education development and teaching strategies for students. The subject, Mystronics, is invented for the larp but lies somewhere between classic grammar and complex systems.Genre: Mystronics class is a research based edularp with a twist of hermetic pseudo-science. Setting: It’s the first time the students will receive teaching about Mystronics. The teacher will experiment with new teaching methods. What conflicts and possibilities will arise? Participant type: For the participants the larp is meant as a fun roleplay experience, but through the larp they will learn about the education research’s view on students and teachers. Character descriptions reflect the types of students and teachers that researchers have identified.
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| 3. |
- Bruun, Jesper, et al.
(author)
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Network analysis and qualitative discourse analysis of a classroom group discussion
- 2019
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In: International Journal of Research and Method in Education. - Abingdon-on-Thames : Routledge. - 1743-727X .- 1743-7288. ; 42:3, s. 317-339
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Journal article (peer-reviewed)abstract
- A new methodology is proposed for qualitative discourse analysis (QDA) aimed at gaining enhanced insights into learning possibilities and indicators that arise during classroom group discussions. The constitution of this new methodology has two principle components: a discourse analysis approach that aims to identify the relationships between content and group dynamics; and a network analysis (NA) approach that uses the same data to identify meaning-related structural dynamics found in the data. The proposed methodology pairs these two components to create a supplementary iterative interchange that facilitates the attainment of greater analytic insights than are achievable by either of the two components individually. The critical aspects of the methodology are illustrated and discussed using real classroom data in ways that provide a procedural exemplar. The strengths and limitations of the proposed methodology are also discussed.
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| 4. |
- Ellegaard, Marianne, et al.
(author)
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Patterns in the form of formative feedback and student response
- 2018
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In: Assessment & Evaluation in Higher Education. - : Informa UK Limited. - 0260-2938 .- 1469-297X. ; 43:5, s. 727-744
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Journal article (peer-reviewed)abstract
- Formative feedback currently receives attention as an effective means of increasing student learning. However, how to frame feedback to achieve the best effect is an ongoing debate. In this study we analyse a written data-set of 174 segments of teacher feedback and student response, coded using 10 emergent feedback and 14 response categories. As it is argued that feedback is a dialogue between students and teacher, links between feedback and response segments are viewed as a dialogical framework that we visualise and understand using network analysis. From this network we conclude that some ways of formulating feedback are more productive and likely to lead to types of responses that signify learning than others. We thus identify the reflection group of responses, consisting of the categories reflective response, explanation and students investigate own thinking. The feedback categories that link primarily to the reflection group are open question, wondering question and leading question, which we categorise as the questioning group of feedback. We discuss these patterns against a previously published framework, and by discussing specific examples we further our understanding of what makes feedback formative.
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| 5. |
- Ellegaard, Marianne, et al.
(author)
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Unfolding principles for student peer feedback: A comparative analysis across higher education contexts
- 2022
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In: Högre Utbildning. - : Cappelen Damm AS - Cappelen Damm Akademisk. - 2000-7558. ; 12:2, s. 53-77
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Journal article (peer-reviewed)abstract
- In this paper we conceptualize formative peer feedback principles by analyzing and comparing six empirical examples of formative peer feedback in a set of international STEM (science, technology, engineering, and mathematics) contexts. By discussing how different approaches to peer feedback unfold in practice, we aim to facilitate the bridging of the gap between theory and practice in implementing peer feedback in Higher Education. As a group of researchers and teaching practitioners from six Higher Education institutions, we discussed, analyzed, and synthesized practical examples of peer feedback in STEM that cover a breadth of settings, aims, and forms. The analysis and comparison of these examples illustrate how principles in peer feedback emerge in practice. We discuss how the context in peer feedback influences its practical implementation, particularly with regard to its purpose and aims, the development and use of assessment criteria, and embedding and supporting the initiatives into the teaching and learning activities.
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| 6. |
- Kattge, Jens, et al.
(author)
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TRY plant trait database - enhanced coverage and open access
- 2020
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In: Global Change Biology. - : Wiley-Blackwell. - 1354-1013 .- 1365-2486. ; 26:1, s. 119-188
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Journal article (peer-reviewed)abstract
- Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives.
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| 7. |
- Lindahl, Mats, 1955-, et al.
(author)
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Integrating text-mining, network analysis and thematic discourse analysis to produce maps of student discussions about sustainability
- 2016
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In: A methodological approach to PER.
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Conference paper (peer-reviewed)abstract
- We use a combination of network analysis (NA), text-mining (TM) techniques, and thematic discourse analysis (TDA) to characterise and compare student discussions about sustainable development. Three student groups at three different times were analysed. The analysis entails an iterative design where NA, TM, and TDA continuously inform each other to produce a rich and coherent picture of the discussions. The output of such an analysis is a set of maps of these discussions, which have both qualitative and quantitative uses. Qualitatively, the maps show how thematic patterns in the discussions are related for each group, and we can see how discourses differ between groups as well as over time. Quantitatively, we use network motif analysis, entropy based measures, and degree distributions to distinguish between discussions.
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| 8. |
- Linder, Cedric, 1954-, et al.
(author)
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Relationship between semiotic representations and student performance in the context of refraction
- 2024
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In: Physical Review Physics Education Research. - : American Physical Society. - 2469-9896. ; 20:1
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Journal article (peer-reviewed)abstract
- Social semiotic discussions about the role played by representations in effective teaching and learning in areas such as physics have led to theoretical proposals that have a strong common thread: in order to acquire an appropriate understanding of a particular object of learning, access to the disciplinary relevance aspects in the representations used calls for the attainment of representational competence across a particular critical constellation of systematically used semiotic resources (which are referred to as modes, see more on this later). However, an affirming empirical investigation into the relationship between a particular object of learning and different representational formulations, particularly with large numbers of students, is missing in the literature, especially in the context of university -level physics education. To start to address, this research shortfall the positioning for this article is that such studies need to embrace the complexities of student thinking and application of knowledge. To achieve this, both factor and network analyses were used. Even though both approaches are grounded in different frameworks, for the task at hand, both approaches are useful for analyzing clustering dynamics within the responses of a large number of participants. Both also facilitate an exploration of how such clusters may relate to the semiotic resource formulation of a representation. The data were obtained from a questionnaire given to 1368 students drawn from 12 universities across 7 countries. The questionnaire deals with the refraction of light in introductorylevel physics and involves asking students to give their best prediction of the relative visual positioning of images and objects in different semiotically constituted situations. The results of both approaches revealed no one-to-one relationship between a particular representational formulation and a particular cluster of student responses. The factor analysis used correct answer responses to reveal clusters that brought to the fore three different complexity levels in relation to representation formulation. The network analysis used all responses (correct and incorrect) to reveal three structural patterns. What is evident from the results of both analyses is that they confirm two broad conclusions that have emerged from social semiotic explorations dealing with representations in relation to attempting to optimize teaching and learning. The first, which is linked to a facilitating -awareness perspective, is that any given disciplinary visual representation can be expected to evoke a dispersed set of knowledge structures, which is referred to as their relevance structure. Thus, the network analysis results can be seen as presenting a unique starting point for studies aiming to identify such relevance structure. The second broad conclusion is that disciplinary visual representation can and often does contain more disciplinary -relevant aspects than what may be directly visible in a given representation. These are referred to as the appresent aspects that need to become part of the total awareness needed by someone to constitute an intended meaning. The results of the factor analysis can then also be seen to be a way of capturing all the disciplinary -relevant aspects (both present and appresent). Educational implications are discussed.
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| 9. |
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| 10. |
- Nouri, Jalal, et al.
(author)
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Efforts in Europe for Data-Driven Improvement of Education – A review of learning analytics research in seven countries
- 2019
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In: International journal of learning analytics and artificial intelligence for education. - : International Association of Online Engineering (IAOE). - 2706-7564. ; 1:1, s. 8-27
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Journal article (peer-reviewed)abstract
- Information and communication technologies are increasingly mediating learning and teaching practices as well as how educational institutions are handling their administrative work. As such, students and teachers are leaving large amounts of digital footprints and traces in various educational apps and learning management platforms, and educational administrators register various processes and outcomes in digital administrative systems. It is against such a background we in recent years have seen the emergence of the fast-growing and multi-disciplinary field of learning analytics. In this paper, we examine the research efforts that have been conducted in the field of learning analytics in Austria, Denmark, Finland, Norway, Germany, Spain, and Sweden. More specifically, we report on developed national policies, infrastructures and competence centers, as well as major research projects and developed research strands within the selected countries. The main conclusions of this paper are that the work of researchers around Europe has not led to national adoption or European level strategies for learning analytics. Furthermore, most countries have not established national policies for learners’ data or guidelines that govern the ethical usage of data in research or education. We also conclude, that learning analytics research on pre-university level to high extent have been overlooked. In the same vein, learning analytics has not received enough focus form national and European national bodies. Such funding is necessary for taking steps towards data-driven development of education.
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| 11. |
- Pérez-García, M. A., et al.
(author)
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Hubble constant and nuclear equation of state from kilonova spectro-photometric light curves
- 2022
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In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 666
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Journal article (peer-reviewed)abstract
- The merger of two compact objects of which at least one is a neutron star is signalled by transient electromagnetic emission in a kilonova (KN). This event is accompanied by gravitational waves and possibly other radiation messengers such as neutrinos or cosmic rays. The electromagnetic emission arises from the radioactive decay of heavy r-process elements synthesized in the material ejected during and after the merger. In this paper we show that the analysis of KNe light curves can provide cosmological distance measurements and constrain the properties of the ejecta. In this respect, MAAT, the new Integral Field Unit in the OSIRIS spectrograph on the 10.4 m Gran Telescopio CANARIAS (GTC), is well suited for the study of KNe by performing absolute spectro-photometry over the entire 3600 − 10 000 Å spectral range. Here, we study the most representative cases regarding the scientific interest of KNe from binary neutron stars, and we evaluate the observational prospects and performance of MAAT on the GTC to do the following: (a) study the impact of the equation of state on the KN light curve, and determine to what extent bounds on neutron star (NS) radii or compactness deriving from KN peak magnitudes can be identified and (b) measure the Hubble constant, H0, with precision improved by up to 40%, when both gravitational wave data and photometric-light curves are used. In this context we discuss how the equation of state, the viewing angle, and the distance affect the precision and estimated value of H0.
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