Making and observing visual representations during problem solving : An eye tracking study

This paper presents a case study of following visual attention during collaborative geometry problem solving. We first analyse the emergence and spread of the incorrect idea of curved lines as the optimal shortest solution. Then, we examine the different visual representations made for solution ideas and how these are observed by the collaborating peers.Peer reviewe

Linear response strength functions with iterative Arnoldi diagonalization

We report on an implementation of a new method to calculate RPA strength functions with iterative non-hermitian Arnoldi diagonalization method, which does not explicitly calculate and store the RPA matrix. We discuss the treatment of spurious modes, numerical stability, and how the method scales as the used model space is enlarged. We perform the particle-hole RPA benchmark calculations for double magic nucleus 132Sn and compare the resulting electromagnetic strength functions against those obtained within the standard RPA.Comment: 9 RevTeX pages, 11 figures, submitted to Physical Review

Mathematics and outdoor photography experience - exploration of an approach to mathematical education, based on the theory of Dewey’s aesthetics

Lehden nimi on vaihtunut. Oikea nimi julkaisuvuonna on "LUMAT: International Journal on Math, Science and Technology Education"Based on Dewey’s theory of art, aesthetics, and experiences and photographer Barnbaums’ writing about expanded perception through photography, we conducted a one-day experimental mathematics education unit. Using photography in outdoor conditions had a positive impact on teacher students’ perception of the use of photography for teaching mathematics. To study the changes in students’ visual attention deeper, we used gaze-tracking to analyse one student’s visual attention when walking outdoors after the activity. The gaze data indicated that more visual attention was given to objects he had photographed or discussed during the group activity in comparison to other objects.Based on Dewey’s theory of art, aesthetics, and experiences and photographer Barnbaums’ writing about expanded perception through photography, we conducted a one-day experimental mathematics education unit. Using photography in outdoor conditions had a positive impact on teacher students’ perception of the use of photography for teaching mathematics. To study the changes in students’ visual attention deeper, we used gaze-tracking to analyse one student’s visual attention when walking outdoors after the activity. The gaze data indicated that more visual attention was given to objects he had photographed or discussed during the group activity in comparison to other objects.Peer reviewe

Liuotushoitoarviot Oulun yliopistollisessa sairaalassa vuonna 2017

Tiivistelmä. Iskeeminen aivoverenkiertohäiriö on merkittävä mortaliteetin ja morbiditeetin aiheuttaja. Tutkimuksen tarkoituksena oli selvittää aivoinfarktin akuuttihoidossa käytettävään liuotushoitoon liittyvien vasta-aiheiden frekvenssejä Oulun yliopistollisen sairaalan (OYS) päivystyspotilasaineistosta. Lisäksi erityisenä mielenkiinnon kohteena oli hoitoon pääsyyn liittyvään viipeen keston selvittäminen. Tutkimus oli retrospektiivinen tutkimus. Aineistoon kerättiin OYS:n päivystyspotilaat aikaväliltä 1.9.17–16.12.2017, joilla oli diagnoosina I63 (aivoinfarkti). Potilaiden tiedot kerättiin ESKO-potilastietojärjestelmästä ja päivystyksen HOITU-työkalusta ja analysoitiin SPSS-ohjelmalla. Tutkimusaineistoon tuli 204 aivoinfarktipotilasta, joista 172 (83,4 %) potilasta ei saanut liuotushoitoa. Liuottamattomat jaettiin kahteen ryhmään, sillä perusteella, olivatko he päivystäjän arvion perusteella liuotushoidon piirissä vai eivät. Inkluusiokriteerit liuotushoidolle täyttyivät, mikäli potilas oli hoidossa <4,5 h oireiston alusta, hänellä oli kliinisesti akuutti iskeeminen aivoverenkiertohäiriö ja hän oli ennestään omatoiminen. Indikaatiot täyttäviä oli 37 potilasta ja heidän yleisimmät vasta-aiheensa olivat lievät neurologiset oireet (29,7 %) ja käytössä oleva antikoagulaatiohoito (18,9–21,6 %). Aineiston potilaista 135 ei täyttänyt liuotushoidon indikaatioita ja heillä yleisimmät vasta-aiheet olivat hoidon aikarajan ylittyminen (65,2 %), lievä neurologinen oireisto (50,4 %) ja laaja aivoinfarktialue (7,4 %). Liuotushoidon yleisin vasta-aihe liittyy hoidon aloituksen aikarajan ylittymiseen. Jopa 2/3 osaa potilaista, joilla inkluusiokriteerit eivät täyttyneet, olisivat voineet olla liuotushoitokandidaatteja, mikäli oirekuva olisi tunnistettu ajoissa. Hoitoon pääsyn viive ei tutkimuksen perusteella vaikuttanut liittyvän kuljetuksen kestoon, vaan potilaiden riittämättömään tietoon aivoinfarktiin liittyvistä oireista. Hoitofrekvenssiä voitaisiin kasvattaa lisäämällä väestön valistusta

Teacher-student eye contact during scaffolding collaborative mathematical problem-solving

Teacher’s gaze communicates consciously and unconsciously her pedagogical priorities to the students. By creating and responding to eye contact initiatives, people can communicate both status and affection. This research explores the frequency of teacher-student eye contacts and their connection to teachers’ scaffolding intentions. The data consisted of mobile gaze tracking recordings of two teachers and stationary classroom videos during three collaborative mathematical problem-solving lessons. The quantitative analysis showed that most of the teacher gazes on student faces did not lead to dyadic eye contacts and those gazes that did, occurred often during affective and cognitive scaffolding. These results offer us novel and important insight in the nonverbal part of scaffolding interaction. Eeva Haataja, Miika Toivanen, Anu Laine and Markku S. Hannula University of Helsinki, FinlandTeacher’s gaze communicates consciously and unconsciously her pedagogical priorities to the students. By creating and responding to eye contact initiatives, people can communicate both status and affection. This research explores the frequency of teacher-student eye contacts and their connection to teachers’ scaffolding intentions. The data consisted of mobile gaze tracking recordings of two teachers and stationary classroom videos during three collaborative mathematical problem-solving lessons. The quantitative analysis showed that most of the teacher gazes on student faces did not lead to dyadic eye contacts and those gazes that did, occurred often during affective and cognitive scaffolding. These results offer us novel and important insight in the nonverbal part of scaffolding interaction.Peer reviewe

Little evidence of range size conservatism in freshwater plants across two continents

[EN] Aim: Range size conservatism suggests that closely-related species maintain geographic ranges of similar extent. However, consensus regarding this suggestion has not been reached. To shed more light on this phenomenon, we studied freshwater plant range size conservatism, range overlap and environmental niche conservatism using congeneric species comparison in two continents. In addition, we investigated whether a phylogenetic signal is found in the range sizes of aquatic plants. Location: Europe and North America. Taxon: Freshwater plants. Methods: Across spatial resolutions (50 km2, 100 km2 and 200 km2), we applied Spearman correlations among 347 and 730 pairs of congeneric species in Europe and North America, respectively, and 63 pairs shared between them. In addition, Spearman correlations were used to evaluate how the degree of spatial overlap influences range sizes and which environmental variables explain variation in range sizes. Brownian evolutionary model was used to assess the phylogenetic signal in species range sizes. Results: We found no evidence of range size conservatism across spatial resolutions for any species and species shared between the continents. In addition, range sizes of more closely related species did not overlap geographically more than those of distantly related ones and no support for environmental niche conservatism was evidenced. Main conclusions: We found that aquatic plants show no range size conservatism in the Northern Hemisphere. This means that it is challenging to define different range sizes of freshwater plants through species traits. Furthermore, we are unable to predict unknown distributions of extant aquatic plant species based on known distributional attributes of closely related species. However, our findings suggest that the interpretations of previous investigations on the range sizes of aquatic plants remain valid due to lack of range size conservatism. These practical implications encourage studying range size conservatism across realms and regions, especially for understudied organismal groupsS

Fully-Renormalized QRPA fulfills Ikeda sum rule exactly

The renormalized quasiparticle-RPA is reformulated for even-even nuclei using restrictions imposed by the commutativity of the phonon creation operator with the total particle number operator. This new version, Fully-Renormalized QRPA (FR-QRPA), is free from the spurious low-energy solutions. Analytical proof is given that the Ikeda sum rule is fullfiled within the FR-QRPA.Comment: 9 page