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Open access articles by University of Helsinki researchers. Contains final versions and manuscripts of research articles as well as professional publications and publications aimed at general public.

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  • Hakyemez-Paul, Sevcan; Lähteenmäki, Marko; Pihlaja, Päivi (2021)
    The aim of this study was to analyse the similarities and differences between the views of early childhood educators on parental involvement and their parental involvement practices in Finland and Turkey. Previous studies have indicated a gap between the rhetoric and practice of parental involvement practices and of insufficient parental involvement. In this study, the reasons for these insufficient practices were also investigated. A binary comparison was applied between Turkey and Finland. A questionnaire was developed based on Epstein’s overlapping spheres of influence model. Altogether 515 early childhood educators from Helsinki and Ankara completed this comprehensive questionnaire. Quantitative methods were used for data analysis. The results showed that Turkish and Finnish early childhood educators have positive views on parental involvement, but Turkish early childhood educators implement all types of parental involvement with significantly greater frequency than their Finnish colleagues.
  • Tervaniemi, Mari; Makkonen, Tommi; Nie, Peixin (2021)
    We compared music emotion ratings and their physiological correlates when the participants listened to music at home and in the laboratory. We hypothesized that music emotions are stronger in a familiar environment, that is, at home. Participants listened to their self-selected favorite and neutral music excerpts at home and in the laboratory for 10 min in each environment. They completed the questionnaires about their emotional states and gave saliva samples for the analyses of the stress hormone cortisol. We found that in the context of music listening, the participants’ emotion ratings differed between home and the laboratory. Furthermore, the cortisol levels were generally lower at home than in the laboratory and decreased after music listening at home and in the laboratory. However, the modulatory effects of music listening on cortisol levels did not differ between the home and the laboratory. Our exploratory multimethodological data offer novel insight about the psychological and physiological consequences of music listening. These data reveal the sensitivity of the current research methods to investigate human emotions in various contexts without excluding the use of laboratory environment in investigating them.
  • Mikkola, Tuija M; Salonen, Minna K; Kajantie, Eero; Kautiainen, Hannu; Eriksson, Johan G (2020)
    Circulating amino acids are potential markers of body composition. Previous studies are mainly limited to middle age and focus on either fat or lean mass, thereby ignoring overall body composition. We investigated the associations of fat and lean body mass with circulating amino acids in older men and women. We studied 594 women and 476 men from the Helsinki Birth Cohort Study (age 62–74 years). Bioelectrical impedance analysis was used to indicate two main body compartments by fat (fat mass/height2) and lean mass indices (lean mass/height2), dichotomized based on sex-specific medians. Eight serum amino acids were quantified using nuclear magnetic resonance spectroscopy. General linear models were adjusted for age, smoking, and fasting glucose. Higher lean mass index (LMI) was associated with higher concentrations of branched-chain amino acids in both sexes (p ≤ .001). In men, LMI was also positively associated with tyrosine (p = .006) and inversely with glycine (p < .001). Higher fat mass index was associated with higher concentrations of all branched-chain amino acids, aromatic amino acids (phenylalanine and tyrosine), and alanine in both sexes (p ≤ .008). Associations between body composition and amino acids are largely similar in older men and women. The associations are largely similar to those previously observed in younger adults.
  • Kale, Liga; Nakurte, Ilva; Jalakas, Pirko; Kunga-Jegere, Laura; Brosche, Mikael; Rostoks, Nils (2019)
    Arabidopsis thaliana cyclic nucleotide-gated ion channel gene 4 (AtCNGC4) loss-of-function mutant dnd2 exhibits elevated accumulation of salicylic acid (SA), dwarfed morphology, reduced hypersensitive response (HR), altered disease resistance and spontaneous lesions on plant leaves. An orthologous barley mutant, nec1, has been reported to over-accumulate indole-3-acetic acid (IAA) and to exhibit changes in stomatal regulation in response to exogenous auxin. Here we show that the Arabidopsis dnd2 over-accumulates both IAA and abscisic acid (ABA) and displays related phenotypic and physiological changes, such as, reduced stomatal size, higher stomatal density and stomatal index. dnd2 showed increased salt tolerance in root growth assay and significantly reduced stomatal conductance, while maintaining near wt reaction in stomatal conductance upon external application of ABA, and probably consequently increased drought stress tolerance. Introduction of both sid2-1 and fmo1 into dnd2 background resulting in removal of SA did not alter stomatal conductance. Hence, the closed stomata of dnd2 is probably a result of increased ABA levels and not increased SA levels. The triple dnd2sid2abi1-1 mutant exhibited intermediate stomatal conductance compared to dnd2 and abil-1 (ABA insensitive, open stomata), while the response to external ABA was as in abi1-1 suggesting that reduced stomatal conductance in dnd2 is not due to impaired ABA signaling. In conclusion, Arabidopsis dnd2 mutant exhibited ABA overaccumulation and stomatal phenotypes, which may contribute to the observed improvement in drought stress resistance. Thus, Arabidopsis dnd2 mutant may serve as a model for studying crosstalk between biotic and abiotic stress and hormonal response in plants.
  • Schroeder, Heike; Di Gregorio, Monica; Brockhaus, Maria; Thu Thuy Pham, (2020)
  • Harvey, Michael G.; Bravo, Gustavo A.; Claramunt, Santiago; Cuervo, Andres M.; Derryberry, Graham E.; Battilana, Jaqueline; Seeholzer, Glenn F.; McKay, Jessica Shearer; O'Meara, Brian C.; Faircloth, Brant C.; Edwards, Scott; Perez-Eman, Jorge; Moyle, Robert G.; Sheldon, Frederick H.; Aleixo, Alexandre; Smith, Brian Tilston; Chesser, R. Terry; Silveira, Luis Fabio; Cracraft, Joel; Brumfield, Robb T.; Derryberry, Elizabeth P. (2020)
    The tropics are the source of most biodiversity yet inadequate sampling obscures answers to fundamental questions about how this diversity evolves. We leveraged samples assembled over decades of fieldwork to study diversification of the largest tropical bird radiation, the suboscine passerines. Our phylogeny, estimated using data from 2389 genomic regions in 1940 individuals of 1287 species, reveals that peak suboscine species diversity in the Neotropics is not associated with high recent speciation rates but rather with the gradual accumulation of species over time. Paradoxically, the highest speciation rates are in lineages from regions with low species diversity, which are generally cold, dry, unstable environments. Our results reveal a model in which species are forming faster in environmental extremes but have accumulated in moderate environments to form tropical biodiversity hotspots.
  • MoEDAL Collaboration; Acharya, B.; Alexandre, J.; Kalliokoski, Matti; Popa, L. A. (2021)
    Timepix3 devices are hybrid pixel detectors developed within the Medipix3 collaboration at CERN providing a simultaneous measurement of energy (ToT) and time of arrival (ToA) in each of its 256×256 pixels (pixel pitch: 55 µm). The timestamp resolution below 2 ns allows a measurement of charge carrier drift times, so that particle trajectories can be reconstructed in 3D on a microscopic level (z-resolution: 30-60 µm). The 3D trajectory reconstruction methodology developed elsewhere is validated against simulated data providing ground truth information of the incident angles. The detector response functions and the achievable track angular resolutions are determined. For the first time, data taken with Timepix3 in the MoEDAL experiment are presented. After extracting singly charged minimum ionizing particle (MIP) tracks from the mixed radiation field using characteristic track features, their impact angles are evaluated. The directionality of the MIP radiation field is shown in elevation angle (θ) versus azimuthal angle (ϕ) maps, "unfolded" using the simulated detector responses to an omnidirectional radiation field.
  • Benjamin, Saija; Aminkeng Atabong, Alemanji (INFORMATION AGE PUBLISHING, INC, 2017)
    Research in multicultural education and international perspectives
  • Benjamin, Saija; Kuusisto, Arniika (2015)
    Following the changing social fabric in societies, classrooms all over Europe are becoming increasingly plural. While many schools, international schools in particular, have a long tradition in accommodating diversities, and acknowledge the various cultural, ethnic and religious realms, most teacher training programs are not designed to address the increasingly multifaceted self-understandings of the contemporary youth. Central to pluralism and international education are the concepts of identity and worldview. The way these are addressed by educators is directly linked to pupils’ personal development and wellbeing. Moving away from cultural essentialism and Western biases that often predominate education and obscure the complexity of the pupils’ worldviews and identifications, this paper approaches pluralism from a more critical stance. Based on the results of an on-going doctoral study, the ‘expanded’ worldviews and the complex self-understandings of internationally mobile youth are illustrated, and the need to rethink the educational practices addressing these within educational settings is emphasized.
  • Benjamin, Saija; Kuusisto, Arniika (2016)
    This paper examines the limitations of measuring identities as based on pre-selected categories, such as ‘immigrant' or ‘Third Culture Kid', within which the individuals are placed according to particular criteria. Simplified, etic categories fail to mirror the complex identifications of the contemporary individual and strengthen essentialism related to ethnicities, cultures and religions. This paper discusses the problematic related to categorization at both analytical and methodological levels. The need for critical reflection on the use of social categories to portray identities is highlighted in general. The adequacy of surveys to measure and examine identities is questioned in particular. This paper illustrates the need to approach identities from emic-etic perspectives and multiple angles in order to grasp a more multilayered view into the complex nature of identity.
  • Croon, Djuna; Gould, Oliver; Schicho, Philipp; Tenkanen, Tuomas V.; White, Graham (2021)
    We critically examine the magnitude of theoretical uncertainties in perturbative calculations of fist-order phase transitions, using the Standard Model effective field theory as our guide. In the usual daisy-resummed approach, we find large uncertainties due to renormalisation scale dependence, which amount to two to three orders-of-magnitude uncertainty in the peak gravitational wave amplitude, relevant to experiments such as LISA. Alternatively, utilising dimensional reduction in a more sophisticated perturbative approach drastically reduces this scale dependence, pushing it to higher orders. Further, this approach resolves other thorny problems with daisy resummation: it is gauge invariant which is explicitly demonstrated for the Standard Model, and avoids an uncontrolled derivative expansion in the bubble nucleation rate.
  • Ares, Feanor Reuben; Hindmarsh, Mark; Hoyos, Carlos; Jokela, Niko (2021)
    We investigate first order phase transitions in a holographic setting of five-dimensional Einstein gravity coupled to a scalar field, constructing phase diagrams of the dual field theory at finite temperature. We scan over the two-dimensional parameter space of a simple bottom-up model and map out important quantities for the phase transition: the region where first order phase transitions take place; the latent heat, the transition strength parameter alpha, and the stiffness. We find that alpha is generically in the range 0.1 to 0.3, and is strongly correlated with the stiffness (the square of the sound speed in a barotropic fluid). Using the LISA Cosmology Working Group gravitational wave power spectrum model corrected for kinetic energy suppression at large alpha and non-conformal stiffness, we outline the observational prospects at the future space-based detectors LISA and TianQin. A TeV-scale hidden sector with a phase transition described by the model could be observable at both detectors.
  • Nagatsu, Michiru; Lisciandra, Chiara (Springer, 2021)
    The interdisciplinary exchange between economists and psychologists has so far been more active and fruitful in the modifications of Expected Utility Theory than in those of Game Theory. We argue that this asymmetry may be explained by economists' specific way of doing equilibrium analysis of aggregate-level outcomes in their practice, and by psychologists' reluctance to fully engage with such practice. We focus on the notion of belief that is embedded in economists' practice of equilibrium analysis, more specifically Nash equilibrium, and argue that its difference from the psychological counterpart is one of the factors that makes interdisciplinary exchange in behavioral game theory more difficult.
  • Es-safi, Imane; Mechchate, Hamza; Amaghnouje, Amal; Kamaly, Omkulthom Mohamed Al; Jawhari, Fatima Zahra; Imtara, Hamada; Grafov, Andriy; Bousta, Dalila (2021)
    Depression and anxiety are major mental health problems in all parts of the world. These illnesses are associated with a number of risk factors, including oxidative stress. Psychotropic drugs of a chemical nature have demonstrated several side effects that elevated the impact of those illnesses. Faced with this situation, natural products appear to be a promising alternative. The aim of this study was to evaluate the anxiolytic and antidepressant effects of the Petroselinum sativum polyphenols in vivo, as well as its correlated antioxidant properties in vitro. Anxiolytic activity of the extract (50 and 100 mg/kg) was evaluated using the open field and the light-dark chamber tests, while the antidepressant activity was evaluated using the forced swimming test. The antioxidant activity of the extract was evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical test and the FRAP (iron-reducing capacity) test. The phenolic extract showed very powerful anxiolytic and antidepressant-like effects, especially at a dose of 100 mg/kg, decreasing the depressive behavior in mice (decreased immobility time) and also the anxiolytic behavior (tendency for discovery in the center and illuminated areas) better even than those of paroxetine and bromazepam (classic drugs) concomitant with those results the extract also showed an important antioxidant capacity. These preliminary results suggest that Petroselinum sativum exhibits anxiolytic and antidepressant potential for use as a complement or independent phytomedicine to treat depression and anxiety.
  • Andrienko, Gennady; Andrienko, Natalia; Boldrini, Chiara; Caldarelli, Guido; Cintia, Paolo; Cresci, Stefano; Facchini, Angelo; Giannotti, Fosca; Gionis, Aristides; Guidotti, Riccardo; Mathioudakis, Michael; Muntean, Cristina Ioana; Pappalardo, Luca; Pedreschi, Dino; Pournaras, Evangelos; Pratesi, Francesca; Tesconi, Maurizio; Trasarti, Roberto (2021)
    The exponential increase in the availability of large-scale mobility data has fueled the vision of smart cities that will transform our lives. The truth is that we have just scratched the surface of the research challenges that should be tackled in order to make this vision a reality. Consequently, there is an increasing interest among different research communities (ranging from civil engineering to computer science) and industrial stakeholders in building knowledge discovery pipelines over such data sources. At the same time, this widespread data availability also raises privacy issues that must be considered by both industrial and academic stakeholders. In this paper, we provide a wide perspective on the role that big data have in reshaping cities. The paper covers the main aspects of urban data analytics, focusing on privacy issues, algorithms, applications and services, and geo-referenced data from social media. In discussing these aspects, we leverage, as concrete examples and case studies of urban data science tools, the results obtained in the "City of Citizens" thematic area of the Horizon 2020 SoBigData initiative, which includes a virtual research environment with mobility datasets and urban analytics methods developed by several institutions around Europe. We conclude the paper outlining the main research challenges that urban data science has yet to address in order to help make the smart city vision a reality.
  • Palmerio, Erika; Kilpua, Emilia; Witasse, Olivier; Barnes, David; Sánchez‐Cano, Beatriz; Weiss, Andreas J.; Nieves-Chinchilla, Teresa; Möstl, Christian; Jian, Lan K.; Mierla, Marilena; Zhukov, Andrei N.; Guo, Jingnan; Rodriguez, Luciano; Lowrance, Patrick J.; Isavnin, Alexey; Turc, Lucile; Futaana, Yoshifumi; Holmström, Mats (2021)
    Coronal mass ejections (CMEs) and solar energetic particles (SEPs) are two phenomena that can cause severe space weather effects throughout the heliosphere. The evolution of CMEs, especially in terms of their magnetic structure, and the configuration of the interplanetary magnetic field (IMF) that influences the transport of SEPs are currently areas of active research. These two aspects are not necessarily independent of each other, especially during solar maximum when multiple eruptive events can occur close in time. Accordingly, we present the analysis of a CME that erupted on May 11, 2012 (SOL2012-05-11) and an SEP event following an eruption that took place on May 17, 2012 (SOL2012-05- 17). After observing the May 11 CME using remote-sensing data from three viewpoints, we evaluate its propagation through interplanetary space using several models. Then, we analyze in-situ measurements from five predicted impact locations (Venus, Earth, the Spitzer Space Telescope, the Mars Science Laboratory en route to Mars, and Mars) in order to search for CME signatures. We find that all in-situ locations detect signatures of an SEP event, which we trace back to the May 17 eruption. These findings suggest that the May 11 CME provided a direct magnetic connectivity for the efficient transport of SEPs. We discuss the space weather implications of CME evolution, regarding in particular its magnetic structure, and CME-driven IMF preconditioning that facilitates SEP transport. Finally, this work remarks the importance of using data from multiple spacecraft, even those that do not include space weather research as their primary objective.
  • Solin, Heikki (Suomen Rooman-instituutti, 2020)
    Acta Instituti Romani Finlandiae
  • Solin, Heikki; Tuomisto, Pekka (2020)
  • Juuti, Kalle; Kairavuori, Seija; Kallioniemi, Arto (2018)
  • Marsh, Jackie; Blum-Ross, Alicia; Kumpulainen, Kristiina (Routledge, 2020)

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