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  • 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.
  • 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.
  • 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.
  • Ahonen, Pertti Pellervo (ResearchGate, 2015)
    The purpose of this article is an examination informed by neo-institutional political and related research on two foremost aspects of institutionalization, performance and legitimation. Political research published by scholars of the extended Baltic region by late May r 2013 comprises the study topic. The article considers political research in four selected subfields: general political science, international relations/world politics, public policy, and public administration/public management. The results indicate that Denmark and Norway are “great powers” in the region, with a strong presence in strongly legitimate publication arenas of political research. Looking further at the performance suggested by publications and citations to these, Sweden and Finland stand out no less than Denmark and Norway, and Estonia and Lithuania also receive visibility. Examining performance with the bibliometric “h” index suggests that “size matters”, which accentuates German achievements, although Norway, Denmark and Sweden continue to stand out despite their relatively small population size.
  • Kaasalainen, Ulla; Heinrichs, Jochen; Krings, Michael; Myllys, Leena; Grabenhorst, Heinrich; Rikkinen, Jouko; Schmidt, Alexander R. (Public Library of Science, 2015)
    One of the most important issues in molecular dating studies concerns the incorporation of reliable fossil taxa into the phylogenies reconstructed from DNA sequence variation in extant taxa. Lichens are symbiotic associations between fungi and algae and/or cyanobacteria. Several lichen fossils have been used as minimum age constraints in recent studies concerning the diversification of the Ascomycota. Recent evolutionary studies of Lecanoromycetes, an almost exclusively lichen-forming class in the Ascomycota, have utilized the Eocene amber inclusion Alectoria succinic as a minimum age constraint. However, a re-investigation of the type material revealed that this inclusion in fact represents poorly preserved plant remains, most probably of a root. Consequently, this fossil cannot be used as evidence of the presence of the genus Alectoria (Parmeliaceae, Lecanorales) or any other lichens in the Paleogene. However, newly discovered inclusions from Paleogene Baltic and Bitterfeld amber verify that alectorioid morphologies in lichens were in existence by the Paleogene. The new fossils represent either a lineage within the alectorioid group or belong to the genus Oropogon.
  • Tynkkynen, Veli-Pekka (Helsingin yliopisto, Aleksanteri-instituutti, 2015)
    Through its use of the Arctic, Russia tries to fortify the idea that it is a global Energy Superpower
  • Lönnqvist, Jan-Erik; Hennig-Schmidt, Heike; Walkowitz, Gari (Public Library of Science, 2015)
  • Siljander, Pia Riitta-Maria; Yáñez-Mó, Maria (Co-Action Publishing, 2015)
    In the past decade, extracellular vesicles (EVs) have been recognized as potent vehicles of intercellular communication, both in prokaryotes and eukaryotes. This is due to their capacity to transfer proteins, lipids and nucleic acids, thereby influencing various physiological and pathological functions of both recipient and parent cells.While intensive investigation has targeted the role of EVs in different pathological processes, for example, in cancer and autoimmune diseases, the EV-mediated maintenance of homeostasis and the regulation of physiological functions have remained less explored. Here, we provide a comprehensive overview of the current understanding of the physiological roles of EVs, which has been written by crowd-sourcing, drawing on the unique EV expertise of academia-based scientists, clinicians and industry based in 27 European countries, the United States and Australia. This review is intended to be of relevance to both researchers already working on EV biology and to newcomers who will encounter this universal cell biological system. Therefore, here we address the molecular contents and functions of EVs in various tissues and body fluids from cell systems to organs. We also review the physiological mechanisms of EVs in bacteria, lower eukaryotes and plants to highlight the functional uniformity of this emerging communication system.
  • Prozorov, Sergei (BRILL, 2015)
    The article addresses the attempts of contemporary continental philosophy to develop a politics that would move beyond the Hobbesian logic of the constitution of political community. In their readings of Hobbes, Roberto Esposito and Giorgio Agamben emphasize the nihilistic character of Hobbes’s approach to community. For Esposito, Hobbes’s commonwealth is legitimized by a prior negation of the originary human community in the construction of the state of nature as the state of war. Yet, as Agamben shows, this negative state of nature is never fully transcended by the commonwealth, which persistently reproduces it in the state of exception. These critiques emphasize the complex relation between nature and artifice in Hobbes’s thought, which have profound implications for the attempts to arrive at a ‘post-Hobbesian’ mode of political community. Neither a facile search for a truer, more fundamental state of nature nor an affirmation of artifice and denaturation as constitutive of human community are sufficient to evade the Hobbesian constellation. A genuine move beyond Hobbes would rather consist in thoroughly deactivating the very relation between nature and artifice whereby they become indistinct and no longer negate each other.
  • Lukkarinen, Jani; Mei, Peng; Spohn, Herbert (JOHN/WILEY & SONS, INC., 2015)
    The Hubbard model is a simplified description for the evolution of interacting spin-1/2 fermions on a d-dimensional lattice. In a kinetic scaling limit, the Hubbard model can be associated with a matrix-valued Boltzmann equation, the Hubbard-Boltzmann equation. Its collision operator is a sum of two qualitatively different terms: The first term is similar to the collision operator of the fermionic Boltzmann-Nordheim equation. The second term leads to a momentum-dependent rotation of the spin basis. The rotation is determined by a principal value integral which depends quadratically on the state of the system and might become singular for non-smooth states. In this paper, we prove that the spatially homogeneous equation nevertheless has global solutions in L^\infty(T^d,C^{2x2}) for any initial data W_0 which satisfies the "Fermi constraint" in the sense that 0 = 3. These assumptions suffice to guarantee that, although possibly singular, the local rotation term is generated by a function in L^2(T^d,C^{2x2}).
  • Okuyama, Yûsuke; Pankka, Pekka (American Mathematical Society, 2015)
    We establish a rescaling theorem for isolated essential singularities of quasiregular mappings. As a consequence we show that the class of closed manifolds receiving a quasiregular mapping from a punctured unit ball with an essential singularity at the origin is exactly the class of closed quasiregularly elliptic manifolds, that is, closed manifolds receiving a non-constant quasiregular mapping from a Euclidean space.
  • Sennikov, Alexander Nikolaevich (INTERNATIONAL ASSOCIATION FOR PLANT TAXONOMY, 2015)
  • Du, Mian; Yangarber, Roman (2015)
    Single-document summarization aims to reduce the size of a text document while preserving the most important information. Much work has been done on open-domain summarization. This paper presents an automatic way to mine domain-specific patterns from text documents. With a small amount of effort required for manual selection, these patterns can be used for domain-specific scenario-based document summarization and information extraction. Our evaluation shows that scenario-based document summarization can both filter irrelevant documents and create summaries for relevant documents within the specified domain.
  • Katajisto, Pekka; Doehla, Julia; Chaffer, Christine L.; Pentinmikko, Nalle; Marjanovic, Nemanja; Iqbal, Md Sharif; Zoncu, Roberto; Chen, Walter; Weinberg, Robert A.; Sabatini, David M. (AAAS, American Association for the Advancement of Science, 2015)
    By dividing asymmetrically, stem cells can generate two daughter cells with distinct fates. However, evidence is limited in mammalian systems for the selective apportioning of subcellular contents between daughters. We followed the fates of old and young organelles during the division of human mammary stemlike cells and found that such cells apportion aged mitochondria asymmetrically between daughter cells. Daughter cells that received fewer old mitochondria maintained stem cell traits. Inhibition of mitochondrial fission disrupted both the age-dependent subcellular localization and segregation of mitochondria and caused loss of stem cell properties in the progeny cells. Hence, mechanisms exist for mammalian stemlike cells to asymmetrically sort aged and young mitochondria, and these are important for maintaining stemness properties.
  • Gel'man, Vladimir (Russian Analytical Digest, 2015)
  • Ajao, Charmaine; Andersson, Maria; Teplova, Vera V; Nagy, Szabolcs; Gahmberg, Carl G.; Andersson, Leif C.; Hautaniemi, Maria; Kakasi, Balazs; Roivainen, Merja; Salkinoja-Salonen, Mirja Sinikka (Elsevier, 2015)
    Effects of triclosan (5-chloro-2’-(2,4-dichlorophenoxy)phenol) on mammalian cells were investigated using human peripheral blood mono nuclear cells (PBMC), keratinocytes (HaCaT), porcine spermatozoa and kidney tubular epithelial cells (PK-15), murine pancreatic islets (MIN-6) and neuroblastoma cells (MNA) as targets. We show that triclosan (1 – 10 μg ml-1) depolarised the mitochondria, upshifted the rate of glucose consumption in PMBC, HaCaT, PK-15 and MNA, and subsequently induced metabolic acidosis. Triclosan induced a regression of insulin producing pancreatic islets into tiny pycnotic cells and necrotic death. Short exposure to low concentrations of triclosan (30 min, ≤ 1 μg / ml) paralysed the high amplitude tail beating and progressive motility of spermatozoa, within 30 min exposure, depolarized the spermatozoan mitochondria and hyperpolarised the acrosome region of the sperm head and the flagellar fibrous sheath (distal part of the flagellum). Experiments with isolated rat liver mitochondria showed that triclosan impaired oxidative phosphorylation, downshifted ATP synthesis, uncoupled respiration and provoked excessive oxygen uptake. These exposure concentrations are 100 - 1000 fold lower that those permitted in consumer goods. The mitochondriotoxic mechanism of triclosan differs from that of valinomycin, cereulide and the enniatins by not involving potassium ionophoric activity.
  • Montovan, Kathryn J.; Couchoux, Christelle; Jones, Laura E.; Reeve, Hudson K.; van Nouhuys, Saskya (UNIVERSITY OF CHICAGO PRESS, 2015)
    When there is conspicuous underexploitation of a limited resource, it is worth asking, what mechanisms allow presumably valuable resources to be left unused? Evolutionary biologists have generated a wide variety of hypotheses to explain this, ranging from interdemic group selection to selfishly prudent individual restraint. We consider a situation in which, despite high intraspecific competition, individuals leave most of a key resource unexploited. The parasitic wasp that does this finds virtually all host egg clusters in a landscape but parasitizes only about a third of the eggs in each and then leaves a deterrent mark around the cluster. We first test—and reject—a series of system-specific simple constraints that might limit full host exploitation, such as asynchronous maturation of host eggs. We then consider classical hypotheses for the evolution of restraint. Prudent predation and bet-hedging fail as explanations because the wasp lives as a large, well-mixed population. Additionally, we find no individual benefits to the parasitoid of developing in a sparsely parasitized host nest.However, an optimal foragingmodel, including empirically measured costs of superparasitism and hyperparasitism, can explain through individual selection both the consistently low rate of parasitism and deterrent marking.
  • Muterko, Alexandr; Balashova, Irina; Cockram, James; Kalendar, Ruslan; Sivolap, Yuri (SPRINGER NEW YORK LLC, 2015)
    Vernalization requirement in hexaploid bread wheat (Triticum aestivum L.) is largely controlled by a series of homoeologous VERNALIZATION (VRN) genes, VRN-A1, VRN-B1 and VRN-D1. Here we analyse sequence from the promoter and first intron of VRN-D1 in 77 hexaploid accessions, representing five wheat species (T. compactum, T. sphaerococcum, T. spelta, T. vavilovii and T. macha) from different eco-geographic areas within 35 countries. Polymorphism was detected for promoter area of VRN-D1 gene. This polymorphism was caused by mutations which are associated with a new haplotype of the Vrn-D1 gene. Analysis of VRN-D1 intron-1 revealed a novel insertional mutation within the ‘vernalization critical’ region in T. spelta and T. compactum. This allelic variant, termed here Vrn-D1s, is predicted to result in vernalization non-responsive alleles. Analysis of the 844 bp insertion revealed it to be a novel transposable DNA-element not previously described in Triticum (DTA_Chimera_KF800714), belonging to the hAT superfamily. Lastly, we describe a PCR-based assay that discriminates the wild-type vrn-D1 allele from the predicted spring Vrn-D1s allele.
    Idäntutkimus-lehden 1/2015 pääkirjoitus