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  • Raekallio, Marja; Saario-Paunio, Elise; Rajamäki, Minna Marjaana; Sankari, Satu Marja; Siven, Mia Susanna; Palviainen, Mari; Peltoniemi, Marikki; Leinonen, Mari-Erika; Honkavaara, Matti Juhana; Vainio, Outi (2010)
  • Räikkönen, Katri; Kajantie, Eero; Pesonen, Anu-Katriina; Heinonen, Kati; Alastalo, Hanna; Leskinen, Jukka T.; Nyman, Kai; Henriksson, Markus; Lahti, Jari; Lahti, Marius; Pyhälä, Riikka; Tuovinen, Soile; Osmond, Clive; Barker, David; Eriksson, Johan G. (Public Library of Science, 2013)
    OBJECTIVES: To examine whether the adverse effects of slow prenatal and postnatal growth on cognitive function persist to old age and predict age related cognitive decline. DESIGN AND SETTING: A longitudinal birth cohort study of men born in Helsinki, Finland 1934-44. PARTICIPANTS: Nine-hundred-thirty-one men of the Helsinki Birth Cohort Study, with detailed data on growth from birth to adulthood, aged 20.1 (SD = 1.4) at the first and 67.9 (SD = 2.5) years at the second cognitive testing. MAIN OUTCOME MEASURES: The Finnish Defense Forces Basic Intellectual Ability Test assessed twice over nearly five decades apart. RESULTS: Lower weight, length and head circumference at birth were associated with lower cognitive ability at 67.9 years (1.04-1.55 points lower ability per each standard deviation [SD] unit decrease in body size, 95% Confidence Interval [95%CI]: 0.05 to 2.72) and with cognitive decline after 20.1 years (0.07-0.11 SD decline over time per each SD decrease in body size, 95%CI:0.00 to 0.19). Men who were born larger were more likely to perform better in the cognitive ability test over time (1.22-1.43 increase in odds to remain in the top relative to the lower two thirds in ability over time per each SD increase in body size, 95%CI:1.04 to 1.79) and were more resilient to cognitive decline after 20.1 years (0.69 to 0.76 decrease in odds to decline from than remain in the top third of ability over time per each SD increase in body size, 95%CI:0.49 to 0.99). Slower growth between birth and two years in weight, height and body mass index was associated with lower cognitive ability at 67.9 years, but not with cognitive decline. CONCLUSIONS: Poorer lifetime cognitive ability is predicted by slower growth before and after birth. In predicting resilience to age related cognitive decline, the period before birth seems to be more critical.
  • Jauhiainen, Sinikka; Laiho, Raija; Vasander, Harri (2002)
    The vegetation of two boreal mires drained for forestry was studied prior to and after restoration (removal of tree stand and filling in of ditches). The restoration induced a rapid rise in the water table level and caused relatively rapid changes in plant species composition and cover. On the minerotrophic fen site, the number of forest species declined and the cover of Eriophorum vaginatum increased five-fold, reaching over 50% cover in three years. On the ombrotrophic bog site, the terrestrial lichens disappeared, while the cover of Empetrum nigrum, Calluna vulgaris, E. vaginatum, and Sphagnum balticum increased. Changes in water table level and vegetation indicate a change towards a functional mire ecosystem.
  • Tack, Ayco J. M.; Laine, Anna-Liisa (WILEY-BLACKWELL PUBLISHING LTD., 2014)
    •While recent studies have elucidated many of the factors driving parasite dynamics during the growing season, the ecological and evolutionary dynamics during the off-season (i.e. the period between growing seasons) remain largely unexplored. •We combine large-scale surveys and detailed experiments to investigate the overwintering success of the specialist plant pathogen Podosphaera plantaginis on its patchily distributed host plant Plantago lanceolata on the Åland Islands. •Twelve years of epidemiological data establish the off-season as a crucial stage in pathogen metapopulation dynamics, with approximately forty percent of the populations going extinct during the off-season. At the end of the growing season, we observed environmentally-mediated variation in the production of resting structures, with major consequences for spring infection at spatial scales ranging from single individuals to populations within a metapopulation. Reciprocal transplant experiments further demonstrated that pathogen population of origin and overwintering site jointly shaped infection intensity in spring, with a weak signal of parasite adaptation to the local off-season environment. •We conclude that environmentally-mediated changes in the distribution and evolution of parasites during the off-season are crucial for our understanding of host-parasite dynamics, with applied implications for combating parasites and diseases in agriculture, wildlife and human disease systems.
  • Niemelä, J. (Kluwer Academic Publishers, 1999)
    Urban areas harbour diverse nature ranging from semi-natural habitats to wastelands, parks and other highly human-in¯uenced biotopes with their associated species assemblages. Maintenance of this urban biodiversity for the residents and for its intrinsic value in the face of increasing population and expanding cities requires that ecological knowledge should be better integrated into urban planning. To achieve this goal understanding of ecological patterns and processes in urban ecosystems is needed. The ®rst step in the necessary urban ecological research is to ®nd out what kind of nature exists in cities. Second, knowledge about ecological processes important in urban nature is required. Although ecological processes in cities are the same as in rural areas, some of them, such as invasion by alien species, are more prevalent in urban than in rural conditions. Third, based on ecological knowledge, management schemes maintaining the diversity of urban nature should be designed. These procedures should also include protection of urban nature, e.g. in urban national parks. Finally, as ecology alone cannot provide the complex information about human in¯uence on urban ecosystems, interdisciplinary research involving natural and social sciences is imperative for a holistic approach to integrating ecology into the process of urban planning.
  • Mäki, Uskali (EDINBURGH UNIVERSITY PRESS, 2005)
    The cultural and epistemic status of science is under attack. Social and cultural studies of science are widely perceived to offer evidence and arguments in support of an anti-science campaign. They portray science as a mundane social endeavour, akin to religion and politics, with no privileged access to truthful information about the (socially unconstructed) real world. Science is under threat and needs defence. Old philosophical legitimations have lost their bite. Alarm bells ring, new troops have to be mobilised. Call economics, the good old friend of the status quo depicting it as a generally beneficial social order while accommodating a rather mundane picture of human behaviour. In contrast to constructivist and relativist sociology of scientific knowledge, economic accounts of science seek to provide a rigorous defence of the cultural and epistemic legitimacy of science by accommodating plausible elements in the sociological accounts and by embedding them in invisible-hand arguments about the functioning of some market-like structure within science. Viewed through economic spectacles, science re-emerges from the ashes as stronger and more beautiful than ever. A spectator raises an innocent question: is economics itself strong and beautiful enough to offer such alleviating services? In order to examine the emerging issue of disciplinary credibility, we need to look at economics itself more closely, and we need to address traditional issues in the philosophy of science as well as less traditional issues of reflexivity. We will see that the above caricature concerning the role of economics in the science wars calls for heavy qualifications if not wholesale rejection (no comment here on the caricatured role of the SSK).
  • Economics 
    Mäki, Uskali (Routledge, 2008)
  • Setälä, Heikki (EASAC Secretariat, The Royal Society, 2009)
  • Nordbo, Annika; Järvi, Leena; Vesala, Timo (2010)
  • Editorial 
    Hurri, Samuli Juha (Samuli Hurri, 2011)
  • Editorial 
    University of Helsinki, Department of Computer Science; University of Helsinki, Department of Computer Science; Roos, Teemu; Myllymäki, Petri; Jaakkola, Tommi; ; ; (ELSEVIER INC., 2012)
  • Sajantila, Antti (BioMed Central Ltd, 2014)
    Abstract No abstract
  • Sajantila, Antti (BioMed Central Ltd, 2014)
  • Norta, Alexander; Ruohomaa, Sini (University of Helsinki, Department of Computer Science, 2011)
    Post-proceedings of the EDOC2011 PhD Student Symposium held in Helsinki 26.8.2011.
  • Kahara, Topi; Tuominen, Kimmo (American Physical Society, 2010)
    We study effective models of chiral fields and Polyakov loop expected to describe the dynamics responsible for the phase structure of two-flavor QCD at finite temperature and density. We consider chiral sector described either using linear sigma model or Nambu-Jona-Lasinio model and study the phase diagram and determine the location of the critical point as a function of the explicit chiral symmetry breaking (i.e. the bare quark mass $m_q$). We also discuss the possible emergence of the quarkyonic phase in this model.
  • Mäkelä, P.; Korkeala, H.; Sand, K. (International Association for Food Protection, 1991)
  • Päivärinta, J.; Lodenius, M. (Springer-Verlag New York Inc., 1994)
  • Djupsund, K.; Fyhrquist, N.; Hariyama, T.; Donner, K. (Elsevier, 1996)
    The threshold intensity for large-long incremental stimuli rises proportionally to adapting background luminance IB (Weber adaptation), but the intensity required to evoke a criterion high-brightness sensation rises much less steeply. We propose that this difference originates in the very first stage of visual processing, in the phototransduction and adaptation properties of the retinal photoreceptor cells. A physiological model previously found to account for visual latency and brightness as functions of stimulus intensity in the dark-adapted state [Donner, K. (1989). Visual Neuroscience, 3, 39–51] is extended to cover different states of adaptation. It is assumed that the neural coding of high intensities is based on the rate of rise (quasi-derivative) of the photoreceptor response just after it reaches a small threshold amplitude. The shallow background adaptation functions for high-brightness criteria emerge as a consequence of the relative constancy of the leading edge of large responses under backgrounds, a phenomenon that can be formally described by compensating changes in photoreceptor sensitivity and time scale. We first test the model on supra-threshold responses in the frog retina, where the discharge rate of ganglion cells (a possible neural code for brightness) and the primary rod hyperpolarizations can be recorded under identical conditions. The two are related as predicted over at least 3 log units of background intensity. We then show that published data on the background adaptation of human foveal high brightness judgments conform to the same model, assuming that human cones accelerate as IB−b with b = 0.14–0.15.
  • Hänninen, Laura; Hepola, Helena; Raussi, Satu; Saloniemi, Hannu (ELSEVIER BV, 2008)
    "In rats, sucking milk reduces anxiety and promotes non-rapid eye movement (NREM) sleep, and in calves it induces resting but the effect on sleep is unknown. Here, we investigated how calves' sleep was affected by colostrum feeding methods. Forty-one calves were blocked by birth date and randomly allotted within blocks to the experimental treatments. Calves were housed for four days either with their dam (DAM) or individually with warm colostrum feeding (2 L four times a day) from either a teat bucket (TEAT) or an open bucket (BUCKET). DAM calves suckled their dam freely. Calves' sleeping and sucking behaviour was filmed continuously for 48 h at the ages of two and three days. Behavioural sleep (BS) was defined as calves resting at least 30 s with their head still and raised (non-rapid eye movement) or with their head against their body or the ground (rapid eye movement, REM). Latency from the end of colostrum feeding to the start of BS was recorded. We compared behaviour of TEAT calves with that of DAM and BUCKET calves using mixed models. Milk meal duration was significantly longer for TEAT calves than for BUCKET calves (mean +/- S.E.M.; 8.3 +/- 0.6 min vs. 5.2 +/- 0.6 min), but equal to that of DAM calves. We found no effect of feeding method on the duration of daily BS (12 h 59 min I h 38 min) but we found a tendency for the daily amount of NREM sleep; BUCKET calves had less NREM sleep per day than TEAT calves (6 h 18 min vs. 7 h 48 min, S.E.M. = 45 min) and also longer latencies from milk ingestion to BS (21.9 +/- 2.0 min vs. 16.2 +/- 2.0 min). DAM calves slept longer bouts than TEAT calves (10.8 +/- 1.0 min vs. 8.3 +/- 1.0 min) and less often (78 +/- 4 vs. 92 +/- 4). Sucking colostrum from a teat bucket compared with drinking from an open"