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  • 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.
  • Laxström, Niklas; Giner, Pau; Thottingal, Santhosh (2015)
    Wikipedia exists in over 280 languages. The quality and quantity of articles in each language varies greatly. Translating from another Wikipedia is a natural way to add more content, but the translation process is not properly supported in the software used by Wikipedia. Past computer assisted translation tools built for Wikipedia (e.g. WikiBasha) are not commonly used. We created a new tool that adapts to the specific needs of an open community and the specifics of the kind of content in Wikipedia. Qualitative and quantitative data indicates that the new tool helps users to translate articles easier and faster.
  • 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.
  • Lindström, Jan Krister; Auer, Peter (University of Bayreuth, 2015)
    In this paper, we argue that the suggested mirror-equivalence of ‘left-’ and ‘right-’ adjoined or -positioned constituents in syntax is misleading from the point of view of Interac-tional Linguistics and needs to be replaced by a positionally sensitive grammatical analysis, in which pre- and post-positioning is seen in the context of the sequential unfolding of conversa-tion in time. We show this on the basis of various examples from conversational German and Swedish. Our main empirical focus is on pre- and post-positioned verba sentiendi expressions of the type ich denke… or jag tror (cf. English ‘I think’). A quantitative analysis shows that these expressions have an uneven distribution in pre- and post-position, as well as in different discourse genres. In a sequential analysis, we can see a positionally sensitive differentiation with respect to syntactic integration and interactional meaning, especially with reference to the dynamics of stance taking and turn taking.
  • 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}).
  • Sennikov, Alexander Nikolaevich (INTERNATIONAL ASSOCIATION FOR PLANT TAXONOMY, 2015)
  • 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.
  • 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.
    Idäntutkimus-lehden 1/2015 pääkirjoitus
  • Pihkala, Panu (2015)
    Environmental theology (or, ecotheology) developed slowly during the first half of the twentieth century and has become a major field of study since the late 1960s. While many of the issues discussed in ecotheological works have included consequences for food production and eating habits, these themes were often not explicitly discussed. The reasons for this are interesting and complex. Issues related to food have been culturally very sensitive and have manifold connections to religiosity. In regard to the discussion about the rights and value of animals, controversies have been seen to arise between ecotheology and ‘animal theology’. Recently, a new interest has arisen in the themes of food, eating, and Christian theology, which has resulted in a new field of literature which could be called the ‘theology of eating’. This article gives an overview of the relations between these fields, with an emphasis on both early ecotheology and new literature about the theology of eating.
  • 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.
  • Kahanpää, Jere; Zatwarnicki, Tadeusz (Pensoft Publishers, 2015)
    The recent checklist of the Ephydridae of Finland by Zatwarnicki and Kahanpää (2014) mentioned 13 ephydrid species as new for Finland without further details. This paper presents detailed records for those species and a few other species of interest. Four species are recorded for the first time from Russia. junior synonym of Trimerina microchaeta Trimerina in distincta Krivosheina, 2004 is herein considered as a new Hendel, 1932, syn. nov.
  • Tiittula, Liisa (KAINUUN SANOMAT, 2015)
  • Mustajoki, Arto Samuel; Teeri, Tuula (Elinkeinoelämän valtuuskunta, 2015)