Articles from TUHAT CRIS

 

Kokoelma sisältää TUHAT-tutkimustietojäjestelmän kautta tallennetut Open Access-artikkelit.

Helsingin yliopiston tutkijat voivat rinnakkaistallentaa tutkimusjulkaisujansa HELDAan liittämällä kokotekstin julkaisuun TUHAT-tutkimustietojärjestelmässä. (Toimintaohje tutkijalle)

This collection contains Open Access articles deposited from the University of Helsinki TUHAT CRIS

Recent Submissions

  • Kimanen, Anuleena (Espoon kaupunki, 2015)
  • Eranti, Veikko Oskari; Lonkila, Markku Kalle (FIRST MONDAY EDITORIAL GROUP, 2015)
    In this paper we study social aspects of using the Like button for purposes of impression management, identity construction, and maintenance of social ties online. On the theoretical level our investigation combines Goffman’s notion of face-work with concepts of social network analysis, shedding light on what we dub ‘nano-level’ interaction and sociality on social networking sites. Our data come from a 2013 classroom survey in which 26 Finnish university students were asked about their motives for and ways of using the Like button. Our results show that though the Like button was designed to allow users to express their positive evaluations of the contents of Facebook posts, comments, and pictures, it was in actual fact used for a wide variety of purposes, from dating efforts to conversation regulation and maintenance of social ties. Our results also reveal that the networked Facebook audience affects the users’ liking behavior, and that users reflect their liking based on previous likes.
  • Villi, Mikko (ROUTLEDGE, 2015)
  • Helsingin yliopisto, Institutionen för lärarutbildning; Dervin, Fred; (L'Harmattan, 2015)
    L’identité est dorénavant un thème central dans les sciences humaines et sociales à travers le monde. Celle-ci pose de nombreux obstacles aux chercheurs qui s’y intéressent, notamment au niveau méthodologique. En effet, comment analyser et traduire la fluidité de l’identité en évitant de figer ses composantes ? Cet ouvrage propose de partir des focus groups pour travailler la question des identités de façon dynamique, réflexive et complexe. Les auteurs décrivent diverses façons d’utiliser les focus groups pour théoriser et étudier l’identité dans différents contextes de recherche (éducation, relations familiales, identité nationale). L’ouvrage intéressera tant les chercheurs que les professeurs et leurs étudiants. Ont collaboré à cet ouvrage : Bruno Bourassa, Andrés Davila Legerén, Sophie Duchesne, Chantal Leclerc, Christian Macé, Ivana Marková, France Picard, Enrique Santamaría et Catherine Sellenet.
  • Tupasela, Aaro Mikael; Snell, Karoliina; Canada, Jose A. (Springer, 2015)
    This article poses the question of whether biobanking practices and standards are giving rise to the construction of populations from which various biobanking initiatives increasingly draw on for legitimacy? We argue that although recent biobanking policies encourage various forms of engagement with publics to ensure legitimacy, different biobanks conceptualize their engagement strategies very differently. We suggest that biobanks undertake a broad range of different strategies with regard to engagement. We argue that these different approaches to engagement strategies are contributing to the construction of populations, whereby specific nationalities, communities, societies, patient groups and political systems become imbued or bio-objectified with particular characteristics, such as compliant, distant, positive, commercialized or authoritarian. This bio-objectification process is problematic in relation to policy aspirations ascribed to biobanking engagement since it gives rise to reified notions of different populations.
  • Cruise, Sharon; Hughes, John; Bennett, Kathleen; Kouvonen, Anne Maria; Kee, Frank (Centre for Ageing Research and Development in Ireland (CARDI), 2015)
  • Wernert, Pauline; Chopin, Francis; Stipska, Pavla; Schulmann, Karel; Bosch, Delphine; Bruguier, Olivier; El Houicha, Mohamed; Corsini, Michel; Ghienne, Jean-François (2015)
    The Morocco Variscan belt is considered to be the south−western continuation of the European Carboniferous orogen on the NW Gondwana margin. The Rehamna Massif, a paleozoic massif located on the Meseta domain which is part of this belt, is affected by three main deformation events (D1, D2 and D3) of variable intensity and geometry, associated with a Barrovian metamorphism. The first forms a flat-lying metamorphic foliation S1, which is deformed by WSW−ENE trending F2 folds with associated sub-vertical S2 cleavage, then heterogeneously reworked by NNE−SSW trending F3 folds with an S3 cleavage moderately to steeply dipping to ESE. Each deformation lead to the development of a new foliation and the crystallisation-deformation relationships show that biotite, chlorite, garnet, chloritoid and staurolite grew in the S1 fabric, and that chloritoid and staurolite continued their growth in the S2 and S3 fabrics. Two types of andalusite porpyroblasts located around granitic intrusions were identified: some are clearly post-tectonic whereas others are presumably coming from an early event. This study combines crystallisation-deformation relationships, in addition to the results of mineral chemistry and mineral zoning, with pseudosection modelling and geochronological datas. Based on the resulting P-T-d paths, three main tectonic events have been recognized: 1) Southward thrusting of an Ordovician sequence over the Proterozoic basement, its Cambrian sedimentary cover and the overlying Devono-Carboniferous basin. This event caused subhorizontal shearing and prograde Barrovian metamorphism of the buried rocks. 2) Continuous shortening resulting first in continuation of burial, then in the development of a syn-convergent extrusion of metamorphosed units to form a dome elongated E–W. This was responsible for syn-convergent detachment of the Ordovician upper crustal sequence. 3) The next episode of convergence took place in a ESE–WNW direction orthogonal to the previous one and is characterized by the accretion of the Rehamna dome to the continental basement in the west. Existing Ar/Ar dating shows that the first and the second deformations occurred during the Late Carboniferous to Early Permian (315-290 Ma) and that the third deformation took place during the Early Permian (290-275 Ma). Geochronology with in situ U/Pb dating on monazites is performed in order to date the individual phases of metamorphism and constrain the timing of the deformations events.
  • Chopin, Francis; Korja, Annakaisa; Hölttä, Pentti; Eklund, Olav; Rämö, Osmo Tapani (2015)
    The Vaasa migmatitic complex, or Vaasa dome, is cored by diatexite migmatites and S-type granitoids and gradually mantled by metatexite migmatites and mica schist with thin metabasite-andesite intercalations. Previous geochemical studies have demonstrated that the metasediments are the sources of the melted core: it have been suggested that the complex have been formed by in-situ melting of a basin. Field work studies highlight the formation of a gently dipping metamorphic fabric with a lateral increase of the in-situ melt content towards the core of the dome (D1). This early layered and partially melted fabric is then affected by a regional N-S shortening forming km- to outcrop-scale E-W striking folds and new sub-vertical foliation (D2). Late sub-vertical shearing is visible along the dome border and within the diatexitic zone (D3). No late detachment structures have been observed. In the metamorphic belt, the grade increases from medium-T amphibolite facies to low-P granulite facies towards the core of the dome. Pseudosections in the MnNCKFMASHTO system have been performed in one mica schist (Grt+BtPl+Qz±Std+Sill+And) and one metatexite migmatite (Bt+Liq+Crd+Pl+Kfs+Grt+Qz±Sill+And). The metamorphic peaks are bracketed at 560°C at 5 kbar and 750-770°C at 4.5-5 kbar, respectively. The retrograde condition is situated at 540°C and <3 kbar for both lithologies. This implies an isobaric increase of the metamorphic grade towards the core of the dome. An isothermal decompression for the schist and a retrograde PT path for the migmatites are observed. Existing and new U/Pb monazite ages from mica schists, migmatites and clustered at 1860–1865 Ma whereas U/Pb ages from metamorphic and magmatic zircons are older and clustered at 1875 Ma. The latter might represent the peak of melting process and associated metamorphism whereas monazites ages might be related to the cooling of the orogenic middle crust. It has to be noticed that few monazites from metamorphic rocks of the dome mantle gave ages similar to those of upper crustal pegmatites, i.e about 1800 Ma. The formation of the Vaasa dome might be the result of thickening during a persistent high-temperature thermal anomaly. It forms a layered middle crust with a strong lateral increase of in-situ melt (D1), followed by a regional N–S horizontal shortening (D2). The culmination of the thickening and the associated metamorphism takes place at 1875 Ma. Exhumation and concomitant cooling of the dome along subvertical shear zone is bracketed at 1860–1865 Ma. This might be correlated with the geodynamic setting of the Svecofenian orogen. After its formation in a back-arc setting at around 1910 Ma, the basin is thickened within a fore arc system in front of a pre-existing arc. An orogenic scale N–S shortening, possibly associated with the formation of an orocline at 1870–1860 Ma might be responsible for the final configuration of the orogen. The origin of the thermal anomaly in the Vaasa dome is still disputed. Heat source inherited from the back-arc basin, radioactive decay, thickening, magma underplating in lower crust and/or delamination might have generated the thermal positive anomaly.
  • Mõttus, Matti; Takala, Tuure Leo Henrik; Stenberg, Teresa Pauline; Knyazikhin, Yuri; Yang, Bin; Nilson, Tiit (ELSEVIER BV, 2015)
  • Tenkanen, Henrikki Toivo Olavi; Salonen, Maria; Lattu, Matti Petteri; Toivonen, Tuuli Kaarina (PERGAMON, 2015)
    Accessibility and transportation possibilities are key factors influencing societal conditions and land use patterns in rural areas. Thus, information on the spatial patterns of accessibility and transportation can be of paramount importance in understanding regional differences in development, human livelihood and land use patterns. Analysing spatio-temporal transportation patterns is particularly challenging in areas where everyday transportation is based on unscheduled public transportation and a naturally controlled seasonal transportation network, such as rivers. Here, our aim is to provide information on the seasonal dynamics of riverine transportation and its effects on accessibility patterns in Peruvian Amazonia. We analysed riverine transportation speeds using a low-cost GPS-based riverboat observation system. Spatio-temporal accessibility patterns were generalised from the GPS-observations that were classified according to seasons into the high water season, intermediate season and low water season. We show that navigation along the rivers has a clear seasonal and directional (upstream/downstream) variation, which varies with different types of rivers based on channel morphology. In addition, we conducted interviews with local people to study their perceptions of the seasonal changes in navigation and the accuracy of transportation schedules. As the travel distances in Peruvian Amazonia are generally long, seasonal and directional differences have clear impacts on the overall accessibility patterns in the area and on the livelihoods of riverine inhabitants. Furthermore, the lack of clearly scheduled transportation causes considerable uncertainty about transportation options for local communities. The baseline information of the seasonal and directional variation of riverine transportation and travel speeds provided by our work is usable in further accessibility and livelihood analyses for Peruvian Amazonia, but it may also be useful in other areas relying on riverine transportation.
  • Kneifel, Stefan; von Lerber, Annakaisa; Tiira, Jussi; Moisseev, Dmitri; Kollias, Pavlos; Leinonen, Jussi (American Geophysical Union, 2015)
    Recently published studies of triple-frequency radar observations of snowfall have demonstrated that naturally occurring snowflakes exhibit scattering signatures that are in some cases consistent with spheroidal particle models and in others can only be explained by complex aggregates. Until recently, no in situ observations have been available to investigate links between microphysical snowfall properties and their scattering properties. In this study, we investigate for the first time relations between collocated ground-based triple-frequency observations with in situ measurements of snowfall at the ground. The three analyzed snowfall cases obtained during a recent field campaign in Finland cover light to moderate snowfall rates with transitions from heavily rimed snow to open-structured, low-density snowflakes. The observed triple-frequency signatures agree well with the previously published findings from airborne radar observations. A rich spatiotemporal structure of triple-frequency observations throughout the cloud is observed during the three cases, which often seems to be related to riming and aggregation zones within the cloud. The comparison of triple-frequency signatures from the lowest altitudes with the ground-based in situ measurements reveals that in the presence of large (>5 mm) snow aggregates, a bending away in the triple-frequency space from the curve of classical spheroid scattering models is always observed. Rimed particles appear along an almost horizontal line in the triple-frequency space, which was not observed before. Overall, the three case studies indicate a close connection of triple-frequency signatures and snow particle structure, bulk snowfall density, and characteristic size of the particle size distribution.
  • Czarnecki, Krzysztof; Hubaux, Arnaud; Jackson, Ethan; Jannach, Dietmar; Männistö, Tomi Matti (Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2014)
  • Vismantic 
    Xiao, Ping; Linkola, Simo Matias (2015)
    This paper presents Vismantic, a semi-automatic system generating proposals of visual composition (visual ideas) in order to express specific meanings. It implements a process of developing visual solutions from ‘what to say’ to ‘how to say’, which requires both conceptual and visual creativity. In particular, Vismantic extends previous work on using conceptual knowledge to find diverse visual representations of abstract concepts, with the capacity of combining two images in three ways, including juxtaposition, replacement and fusion. In an informal evaluation consisting of five communication tasks, Vismantic demonstrated the potential of producing a number of expressive and diverse ideas, among which many are surprising. Our analysis of the generated images confirms that visual meaning making is a subtle interaction between all elements in a picture, for which Vismantic demands more visual semantic knowledge, higher image analysis and synthesis skills, and the ability of interpreting composed images, in order to deliver more ideas that make sense.
  • Moisy, Cedric; Schulman, Alan H.; Kalendar, Ruslan; Buchmann, Jan P.; Pelsy, Frédérique (SPRINGER, 2014)
    Retrotransposons are ubiquitous throughout the genomes of the vascular plants, but individual retrotransposon families tend to be confined to the level of plant genus or at most family. This restricts the general applicability of a family as molecular markers. Here, we characterize a new plant retrotransposon named Tvv1_Sdem, a member of the Copia superfamily of LTR retrotransposons, from the genome of the wild potato Solanum demissum. Comparative analyses based on structure and sequence showed a high level of similarity of Tvv1_Sdem with Tvv1-VB, a retrotransposon previously described in the grapevine genome Vitis vinifera. Extending the analysis to other species by in silico and in vitro approaches revealed the presence of Tvv1 family members in potato, tomato, and poplar genomes, and led to the identification of full-length copies of Tvv1 in these species. We were also able to identify polymorphism in UTL sequences between Tvv1_Sdem copies from wild and cultivated potatoes that are useful as molecular markers. Combining different approaches, our results suggest that the Tvv1 family of retrotransposons has a monophyletic origin and has been maintained in both the rosids and the asterids, the major clades of dicotyledonous plants, since their divergence about 100 MYA. To our knowledge, Tvv1 represents an unusual plant retrotransposon metapopulation comprising highly similar members disjointedly dispersed among very distant species. The twin features of Tvv1 presence in evolutionarily distant genomes and the diversity of its UTL region in each species make it useful as a source of robust molecular markers for diversity studies and breeding.
  • Kalendar, Ruslan; Lee, David; Schulman, Alan (Humana Press, 2014)
    This chapter introduces the software FastPCR as an integrated tools environment for PCR primer and probe design. It also predicts oligonucleotide properties based on experimental studies of PCR efficiency. The software provides comprehensive facilities for designing primers for most PCR applications and their combinations, including standard, multiplex, long-distance, inverse, real-time, group-specific, unique, and overlap extension PCR for multi-fragment assembly in cloning, as well as bisulphite modification assays. It includes a programme to design oligonucleotide sets for long sequence assembly by the ligase chain reaction. The in silico PCR primer or probe search includes comprehensive analyses of individual primers and primer pairs. It calculates the melting temperature for standard and degenerate oligonucleotides including LNA and other modifications, provides analyses for a set of primers with prediction of oligonucleotide properties, dimer and G/C-quadruplex detection, linguistic complexity, and provides a dilution and resuspension calculator. The program includes various bioinformatics tools for analysis of sequences with GC or AT skew, of CG content and purine-pyrimidine skew, and of linguistic sequence complexity. It also permits generation of random DNA sequence and analysis of restriction enzymes of all types. It finds or creates restriction enzyme recognition sites for coding sequences and supports the clustering of sequences. It generates consensus sequences and analyses sequence conservation. It performs efficient and complete detection of various repeat types and displays them. FastPCR allows for sequence file batch processing, which is essential for automation. The FastPCR software is available for download at http://primerdigital.com/fastpcr.html and online version at http://primerdigital.com/tools/pcr.html.