942 resultados para Plant-environment interaction


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This contribution (presented in the first International Conference on Public Policy (ICPP) in Grenoble in June 2013) explores the phenomena of innovation in action ("innovative implementation"). To do so, we operationalize "innovative implementation" as a strategy by which (coalitions of) non-state actors seek to develop ad hoc solutions to address a given environmental issue, going beyond what is provided for in formal policy designs. Following an inductive research strategy, we elaborate a conceptual framework whose main advantage is to bring the actors and their coalition (in all their diversity) back in the analysis. More concretely, we state that perceiving implementation as broader 'social interaction processes' (De Boer & Bressers 2011) within which actors play strategic 'games' (Bardach 1977, Scharpf 1997) opens interesting lines of research to better account for their innovative and strategic behaviours. In a second step, we apply this framework to three strategies of innovative implementation in different contexts, and identify on this basis empirical regularities in the individual pathways related to the emergence and success (or failure) of these strategies.

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Brain-computer interfaces (BCIs) are becoming more and more popular as an input device for virtual worlds and computer games. Depending on their function, a major drawback is the mental workload associated with their use and there is significant effort and training required to effectively control them. In this paper, we present two studies assessing how mental workload of a P300-based BCI affects participants" reported sense of presence in a virtual environment (VE). In the first study, we employ a BCI exploiting the P300 event-related potential (ERP) that allows control of over 200 items in a virtual apartment. In the second study, the BCI is replaced by a gaze-based selection method coupled with wand navigation. In both studies, overall performance is measured and individual presence scores are assessed by means of a short questionnaire. The results suggest that there is no immediate benefit for visualizing events in the VE triggered by the BCI and that no learning about the layout of the virtual space takes place. In order to alleviate this, we propose that future P300-based BCIs in VR are set up so as require users to make some inference about the virtual space so that they become aware of it,which is likely to lead to higher reported presence.

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Mulching has become an important technique for land cover, but there are some technical procedures which should be adjusted for these new modified conditions to establish optimum total water depth. It is also important to observe the soil-water relations as soil water distribution and wetted volume dimensions. The objective of the present study was to estimate melon evapotranspiration under mulching in a protected environment and to verify the water spatial distribution around the melon root system in two soil classes. Mulching provided 27 mm water saving by reducing water evaporation. In terms of volume each plant received, on average, the amount of 175.2 L of water in 84 days of cultivation without mulching, while when was used mulching the water requirement was 160.2 L per plant. The use of mulching reduced the soil moisture variability throughout the crop cycle and allowed a greater distribution of soil water that was more intense in the clay soil. The clayey soil provided on average 43 mm more water depth retention in 0.50 m soil deep relative to the sandy loam soil, and reduced 5.6 mm the crop cycle soil moisture variation compared to sandy loam soil.

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Oceans, or other wide expanses of inhospitable environment, interrupt present day distributions of many plant groups. Using molecular dating techniques, generally incorporating fossil evidence, we can estimate when such distributions originated. Numerous dating analyses have recently precipitated a paradigm shift in the general explanations for the phenomenon, away from older geological causes, such as continental drift, in favour of more recent, long-distance dispersal (LDD). For example, the 'Gondwanan vicariance' scenario has been dismissed in various studies of Indian Ocean disjunct distributions. We used the gentian tribe Exaceae to reassess this scenario using molecular dating with minimum (fossil), maximum (geological), secondary (from wider analyses) and hypothesis-driven age constraints. Our results indicate that ancient vicariance cannot be ruled out as an explanation for the early origins of Exaceae across Africa, Madagascar and the Indian subcontinent unless a strong assumption is made about the maximum age of Gentianales. However, both the Gondwanan scenario and the available evidence suggest that there were also several, more recent, intercontinental dispersals during the diversification of the group.

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This paper reports an experiment that investigated people"s body ownership of an avatar that was observed in a virtual mirror. Twenty subjects were recruited in a within-groups study where 10 first experienced a virtual character that synchronously reflected their upper-body movements as seen in a virtual mirror, and then an asynchronous condition where the mirror avatar displayed prerecorded actions, unrelated to those of the participant. The other 10 subjects experienced the conditions in the opposite order. In both conditions the participant could carry out actions that led to elevation above ground level, as seen from their first person perspective and correspondingly in the mirror. A rotating virtual fan eventually descended to 2m above the ground. The hypothesis was that synchronous mirror reflection would result in higher subjective sense of ownership. A questionnaire analysis showed that the body ownership illusion was significantly greater for thesynchronous than asynchronous condition. Additionally participants in the synchronous condition avoided collision with the descending fan significantly more often than those in the asynchronous condition. The results of this experiment are put into context within similar experiments on multisensory correlation and body ownership within cognitive neuroscience.

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Tutkielman tavoitteena on selvittää, mihin päätöksenteko perustuu teollisuusyrityksessä. Tutkimuksessa kartoitettiin kohdeorganisaation päätöksentekijöiden näkemyksiä toimintaympäristöstään, itsestään päätöksentekijöinä ja päätöksenteosta sekä tiedosta ja sen käytöstä. Lisäksi sivutaan päätöksenteon sosiaalista luonnetta. Empiirisen tutkimuksen kohdeyksikkönä on UPM-Kymmene Oyj, Kaukas Lappeenrannassa. Tutkimus on toteutettu esimiestasolle suunnattuna lomakekyselynä lokakuussa 2003. Päätöksistä yleisimpiä olivat operatiivisen tason päätökset; taktisen ja strategisen tason päätöksiä tehtiin vähemmän. Päätöstilanteista useimmin kohdattuja olivat puolijäsentyneet ja jäsentyneet tilanteet, kun taas jäsentymättömät päätöstilanteet olivat harvinaisempia. Päätöksentekoprosesseista yleisimmin käytetty oli kirjallisuudessa taktiseen päätöstasoon ja puolijäsentyneisiin päätöstilanteisiin liitetty rajoitetun rationaalisuuden malliin perustuva vaiheittainen malli. Kirjallisuudessa strategiseen päätöksentekotasoon ja jäsentymättömiin päätöstilanteisiin liitetyn ns. iteratiivisesti vaiheittaisen mallin todettiin soveltuvan myös tämänkaltaiseen päätöksentekoon. Esimiehet pitivät toimintaympäristöään teollisuusyrityksessä pääasiallisesti orgaanisena. Tällaisessa ympäristössä vaikutussuhteet ja keinot ohjata ympäristöä perustuvat pitkälti vuorovaikutteisuuteen. Päätöksentekijöiden johtamistyylin todettiin olevan pikemminkin demokraattinen kuin autoritäärinen, mikä tukee edellä mainittuja tuloksia. Tiedon lähteistä päätöksenteon kannalta tärkeimpinä ja luotettavimpina koettiin henkilökohtaiset lähteet. Sisäiset lähteet nähtiin ulkoisia tärkeämpinä ja luotettavampina niin henkilökohtaisten, tekstimuotoisten kuin online-lähteidenkin osalta. Esimiesten todettiin hyödyntävän tosiasiatietoa, kokemusta ja intuitiota eri tavoin erilaisissa päätöstilanteissa, joten myös tehokkaat keinot tukea päätöksentekoa vaihtelevat päätöstyypeittäin. Tutkimuksen tulokset perustuvat kohderyhmän kyselylomakkeella kerättyihin mielipiteisiin. Käytetystä menetelmästä johtuen mielipiteiden taustatekijät ja todellinen toiminta organisaatiossa jäävät vielä avoimiksi. Tutkimustulosten syventäminen ja vahvistaminen sekä lisätiedon saaminen organisaation päätöksenteon todellisuudesta edellyttäisi empiiristä havainnointia tai vähintäänkin haastatteluja.

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Plants must constantly adapt to a changing light environment in order to optimize energy conversion through the process of photosynthesis and to limit photodamage. In addition, plants use light cues for timing of key developmental transitions such as initiation of reproduction (transition to flowering). Plants are equipped with a battery of photoreceptors enabling them to sense a very broad light spectrum spanning from UV-B to far-red wavelength (280-750nm). In this review we briefly describe the different families of plant photosensory receptors and the mechanisms by which they transduce environmental information to influence numerous aspects of plant growth and development throughout their life cycle.

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This study aims at understanding the evolutionary processes at work in specialized species interactions. Prom the macroevolutionary perspective, coevolution among specialized taxa was proposed to be one of the major processes generating biodiversity. We challenge this idea from the theoretical and practical perspective and through a literature review and show that the major hypotheses linking coevolutionary process with macroevolutionary patterns do not necessarily predict lineage co diversification and parallel speciation, limit¬ing the utility of the comparative phylogenenetic approach for investigating coevolution¬ary processes. We also point to the rarity of observed long-term coevolutionary dynamics among lineages and propose that coevolution rather occurs in shorter timescales, followed by ecological fitting. Prom the empirical point, we focus on the nursery pollination interaction between the European globeflower Trollius europaeus (Ranunculaceae) and its associated Chiastocheta flies (Anthomyiidae; Diptera) as a model system of evolution and maintenance of special¬ized interactions. The flies are obligate parasites of the seeds, but also pollinate the plant - it was thus proposed that both species are mutually dependent. Contrasting with the paradigm used for two decades of research on this system, we show that the female fitness component of the plant is similar in the populations with and without Chiastocheta. The plant is thus not exclusively dependent on the flies for reproduction. We discuss this result in the context of the factors responsible for the evolution of mutualistic systems. Understanding the evolution of a biological system requires understanding of its phylo- genetic context. Previous studies showed large mismatch between mtDNA phylogeny and morphological taxonomy in Chiastocheta. By using a large set of RAD-sequencing loci, we delineate the species limits that are congruent with morphology, and show that the discordance is best explained by the scenario of mitochondrial capture among fly species. Finally, we examine this system from a phylogeographic perspective, and identify the lack of congruence in spatial genetic structures of the plant and associated insects across their whole geographic range. The flies show lower numbers of spatial genetic groups than the plant, indicating that not all of the plant réfugia were shared by all the fly species or that the migration dynamics homogenized some of the groups. The incongruence in spatial genetic patterns indicates that fly migrations were largely independent from the genetic background of the plant, following rather a scenario of resource tracking, without the signature of coevolutionary process at this scale. Indeed, while the flies require the plant to survive climatic oscillations, the opposite is not true. Eventually, we show that there is no phylogenetic signal of spatial genetic structures, meaning that neither histories nor life- history traits are shared among closely related species and that species are characterized by unique trajectories of their genes. -- Cette étude vise à comprendre les processus évolutifs à l'oeuvre au sein d'interactions en¬tre espèces spécialisées. Du point de vue macroévolutif, la coévolution entre les taxons spécialisée a été considérée comme l'un des principaux processus générateur de biodiversité. Nous contestons cette idée du point de vue théorique et pratique à travers une revue de la littérature. Nous montrons que les hypothèses majeures reliant les processus coévolutifs avec les patterns de diversité au niveau macroévolutif ne prédisent pas nécessairement la co- diversification des lignées et leur spéciation parallèle, ce qui limite l'utilité de l'approche de phylogénie comparative pour étudier les processus coévolutifs . Nous rappelons également le peu d'exemples de dynamique coévolutive à long terme et proposons que la coévolution se produit plutôt dans des intervalles courts, suivis d'ajustements écologiques. Du point empirique, nous nous concentrons sur l'interaction de pollinisation entre le Trolle d'Europe Trollius europaeus (Ranunculaceae) et ses pollinisateurs associés, du genre Chiastocheta (Anthomyiidae; Diptera) en tant que système-modèle pour étudier l'évolution et le maintien des interactions spécialisées. Les mouches sont des parasites obligatoires des semences, mais pollinisent également la plante. Il a donc été proposé que les deux espèces soient mutuellement dépendantes. Contrastant avec le paradigme utilisé pendant deux décennies de recherche sur ce système, nous montrons, que la composante de fitness femelle de la plante est similaire dans les populations avec et sans Chiastocheta. La plante ne dépend donc pas exclusivement de son interaction avec les mouches pour la reproduction. Nous discutons de ce résultat dans le contexte des facteurs responsables de l'évolution des systèmes mutualistes. Comprendre l'évolution d'un système biologique nécessite la compréhension de son con- texte phylogénétique. Des études antérieures ont montré, chez Chiastocheta, de grandes disparités entre les phylogénies obtenues à partir d'ADN mitochondrial et la taxonomie basée sur les critères morphologiques. En utilisant un grand nombre de loci obtenus par RAD-sequencing, nous traçons les limites des espèces, qui concordent avec les car¬actéristiques morphologies, et montrons que la discordance s'explique en fait par un scénario de capture mitochondriale entre espèces de mouches. Enfin, nous examinons le système d'un point de vue phylogéographique, et identi¬fions les incohérences entre structurations génétiques spatiales de la plante et des insectes associés dans toute leur aire de distribution géographique. Les mouches présentent un nombre de groupes génétiques inférieur à la plante, indiquant que tous les refuges de la plante n'étaient pas partagés par toutes les espèces de mouches ou que les dynamiques migratoires ont homogénéisés certains des groupes chez les mouches. Les différences ob¬servées dans les patrons de structuration génétique spatiale indique que les migrations et dispersions des mouches ont été indépendantes du contexte génétique de la plante, et ces dernières ont été uniquement tributaires de la disponibilité des ressources, sans qu'il n'y ait de signature du processus de coévolution à cette échelle. En effet, tandis que les mouches ont besoin de la plante pour survivre aux oscillations climatiques, le contraire n'est pas exact. Finalement, nous montrons qu'il n'y a pas de signal phylogénétique des structurations génétiques spatiales chez les mouches, ce qui signifie que ni l'histoire, ni les traits d'histoire de vie ne sont partagés entre les espèces phylogénétiquement proches et que les espèces sont caractérisées par des trajectoires uniques de leurs gènes.

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Les bactéries du genre Pseudomonas ont la capacité étonnante de s'adapter à différents habitats et d'y survivre, ce qui leur a permis de conquérir un large éventail de niches écologiques et d'interagir avec différents organismes hôte. Les espèces du groupe Pseudomonas fluorescens peuvent être facilement isolées de la rhizosphère et sont communément connues comme des Pseudomonas bénéfiques pour les plantes. Elles sont capables d'induire la résistance systémique des plantes, d'induire leur croissance et de contrer des phytopathogènes du sol. Un sous-groupe de ces Pseudomonas a de plus développé la capacité d'infecter et de tuer certaines espèces d'insectes. Approfondir les connaissances sur l'interaction de ces bactéries avec les insectes pourraient conduire au développement de nouveaux biopesticides pour la protection des cultures. Le but de cette thèse est donc de mieux comprendre la base moléculaire, l'évolution et la régulation de la pathogénicité des Pseudomonas plante-bénéfiques envers les insectes. Plus spécifiquement, ce travail a été orienté sur l'étude de la production de la toxine insecticide appelée Fit et sur l'indentification d'autres facteurs de virulence participant à la toxicité de la bactérie envers les insectes. Dans la première partie de ce travail, la régulation de la production de la toxine Fit a été évaluée par microscopie à épifluorescence en utilisant des souches rapportrices de Pseudomonas protegens CHA0 qui expriment la toxine insecticide fusionnée à une protéine fluorescente rouge, au site natif du gène de la toxine. Celle-ci a été détectée uniquement dans l'hémolymphe des insectes et pas sur les racines des plantes, ni dans les milieux de laboratoire standards, indiquant une production dépendante de l'hôte. L'activation de la production de la toxine est contrôlée par trois protéines régulatrices dont l'histidine kinase FitF, essentielle pour un contrôle précis de l'expression et possédant un domaine "senseur" similaire à celui de la kinase DctB qui régule l'absorption de carbone chez les Protéobactéries. Il est donc probable que, durant l'évolution de FitF, un réarrangement de ce domaine "senseur" largement répandu ait contribué à une production hôte-spécifique de la toxine. Les résultats de cette étude suggèrent aussi que l'expression de la toxine Fit est plutôt réprimée en présence de composés dérivés des plantes qu'induite par la perception d'un signal d'insecte spécifique. Dans la deuxième partie de ce travail, des souches mutantes ciblant des facteurs de virulence importants identifiés dans des pathogènes connus ont été générées, dans le but d'identifier ceux avec une virulence envers les insectes atténuée. Les résultats ont suggéré que l'antigène O du lipopolysaccharide (LPS) et le système régulateur à deux composantes PhoP/PhoQ contribuent significativement à la virulence de P. protegens CHA0. La base génétique de la biosynthèse de l'antigène O dans les Pseudomonas plante-bénéfiques et avec une activité insecticide a été élucidée et a révélé des différences considérables entre les lignées suite à des pertes de gènes ou des acquisitions de gènes par transfert horizontal durant l'évolution de certaines souches. Les chaînes latérales du LPS ont été montrées comme vitales pour une infection des insectes réussie par la souche CHA0, après ingestion ou injection. Les Pseudomonas plante-bénéfiques, avec une activité insecticide sont naturellement résistants à la polymyxine B, un peptide antimicrobien modèle. La protection contre ce composé antimicrobien particulier dépend de la présence de l'antigène O et de la modification du lipide A, une partie du LPS, avec du 4-aminoarabinose. Comme les peptides antimicrobiens cationiques jouent un rôle important dans le système immunitaire des insectes, l'antigène O pourrait être important chez les Pseudomonas insecticides pour surmonter les mécanismes de défense de l'hôte. Le système PhoP/PhoQ, connu pour contrôler les modifications du lipide A chez plusieurs bactéries pathogènes, a été identifié chez Pseudomonas chlororaphis PCL1391 et P. protegens CHA0. Pour l'instant, il n'y a pas d'évidence que des modifications du lipide A contribuent à la pathogénicité de cette bactérie envers les insectes. Cependant, le senseur-kinase PhoQ est requis pour une virulence optimale de la souche CHA0, ce qui suggère qu'il régule aussi l'expression des facteurs de virulence de cette bactérie. Les découvertes de cette thèse démontrent que certains Pseudomonas associés aux plantes sont de véritables pathogènes d'insectes et donnent quelques indices sur l'évolution de ces microbes pour survivre dans l'insecte-hôte et éventuellement le tuer. Les résultats suggèrent également qu'une recherche plus approfondie est nécessaire pour comprendre comment ces bactéries sont capables de contourner ou surmonter la réponse immunitaire de l'hôte et de briser les barrières physiques pour envahir l'insecte lors d'une infection orale. Pour cela, les futures études ne devraient pas uniquement se concentrer sur le côté bactérien de l'interaction hôte-microbe, mais aussi étudier l'infection du point de vue de l'hôte. Les connaissances gagnées sur la pathogénicité envers les insectes des Pseudomonas plante-bénéfiques donnent un espoir pour une future application en agriculture, pour protéger les plantes, non seulement contre les maladies, mais aussi contre les insectes ravageurs. -- Pseudomonas bacteria have the astonishing ability to survive within and adapt to different habitats, which has allowed them to conquer a wide range of ecological niches and to interact with different host organisms. Species of the Pseudomonas fluorescens group can readily be isolated from plant roots and are commonly known as plant-beneficial pseudomonads. They are capable of promoting plant growth, inducing systemic resistance in the plant host and antagonizing soil-borne phytopathogens. A defined subgroup of these pseudomonads evolved in addition the ability to infect and kill certain insect species. Profound knowledge about the interaction of these particular bacteria with insects could lead to the development of novel biopesticides for crop protection. This thesis thus aimed at a better understanding of the molecular basis, evolution and regulation of insect pathogenicity in plant-beneficial pseudomonads. More specifically, it was outlined to investigate the production of an insecticidal toxin termed Fit and to identify additional factors contributing to the entomopathogenicity of the bacteria. In the first part of this work, the regulation of Fit toxin production was probed by epifluorescence microscopy using reporter strains of Pseudomonas protegens CHAO that express a fusion between the insecticidal toxin and a red fluorescent protein in place of the native toxin gene. The bacterium was found to express its insecticidal toxin only in insect hemolymph but not on plant roots or in common laboratory media. The host-dependent activation of Fit toxin production is controlled by three local regulatory proteins. The histidine kinase of this regulatory system, FitF, is essential for the tight control of toxin expression and shares a sensing domain with DctB, a sensor kinase regulating carbon uptake in Proteobacteria. It is therefore likely that shuffling of a ubiquitous sensor domain during the evolution of FitF contributed to host- specific production of the Fit toxin. Findings of this study additionally suggest that host-specific expression of the Fit toxin is mainly achieved by repression in the presence of plant-derived compounds rather than by induction upon perceiving an insect-specific signal molecule. In the second part of this thesis, mutant strains were generated that lack factors previously shown to be important for virulence in prominent pathogens. A screening for attenuation in insect virulence suggested that lipopolysaccharide (LPS) O-antigen and the PhoP-PhoQ two-component regulatory system significantly contribute to virulence of P. protegens CHAO. The genetic basis of O-antigen biosynthesis in plant-beneficial pseudomonads displaying insect pathogenicity was elucidated and revealed extensive differences between lineages due to reduction and horizontal acquisition of gene clusters during the evolution of several strains. Specific 0 side chains of LPS were found to be vital for strain CHAO to successfully infect insects by ingestion or upon injection. Insecticidal pseudomonads with plant-beneficial properties were observed to be naturally resistant to polymyxin B, a model antimicrobial peptide. Protection against this particular antimicrobial compound was dependent on the presence of O-antigen and modification of the lipid A portion of LPS with 4-aminoarabinose. Since cationic antimicrobial peptides play a major role in the immune system of insects, O-antigenic polysaccharides could be important for insecticidal pseudomonads to overcome host defense mechanisms. The PhoP-PhoQ system, which is well-known to control lipid A modifications in several pathogenic bacteria, was identified in Pseudomonas chlororaphis PCL1391 and P. protegens CHAO. No evidence was found so far that lipid A modifications contribute to insect pathogenicity in this bacterium. However, the sensor kinase PhoQ was required for full virulence of strain CHAO suggesting that it additionally regulates the expression of virulence factors in this bacterium. The findings of this thesis demonstrate that certain plant-associated pseudomonads are true insect pathogens and give some insights into how these microbes evolved to survive within and eventually kill the insect host. Results however also point out that more in-depth research is needed to know how exactly these fascinating bacteria manage to bypass or overcome host immune responses and to breach physical barriers to invade insects upon oral infection. To achieve this, future studies should not only focus on the bacterial side of the microbe-host interactions but also investigate the infection from a host-oriented view. The knowledge gained about the entomopathogenicity of plant-beneficial pseudomonads gives hope for their future application in agriculture to protect plants not only against plant diseases but also against insect pests.

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Plant microRNAs (miRNAs) are important regulatory switches. Recent advances have revealed many regulatory layers between the two essential processes, miRNA biogenesis and function. However, how these multilayered regulatory processes ultimately control miRNA gene regulation and connects miRNAs and plant responses with the surrounding environment is still largely unknown. In this opinion article, we propose that the miRNA pathway is highly dynamic and plastic. The apparent flexibility of the miRNA pathway in plants appears to be controlled by a number recently identified proteins and poorly characterized signaling cascades. We further propose that altered miRNA accumulation can be a direct consequence of the rewiring of interactions between proteins that function in the miRNA pathway, an avenue that remains largely unexplored.

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The objective of the thesis is to enhance the understanding about the management of the front end phases of the innovation process in a networked environment. The thesis approaches the front end of innovation from three perspectives, including the strategy, processes and systems of innovation. The purpose of the use of different perspectives in the thesis is that of providing an extensive systemic view of the front end, and uncovering the complex nature of innovation management. The context of the research is the networked operating environment of firms. The unit of analysis is the firm itself or its innovation processes, which means that this research approaches the innovation networks from the point of view of a firm. The strategy perspective of the thesis emphasises the importance of purposeful innovation management, the innovation strategy of firms. The role of innovation processes is critical in carrying out innovation strategies in practice, supporting the development of organizational routines for innovation, and driving the strategic renewal of companies. The primary focus of the thesis from systems perspective is on idea management systems, which are defined as a part of innovation management systems, and defined for this thesis as any working combination of methodology and tools (manual or IT-supported) that enhance the management of innovations within their early phases. The main contribution of the thesis are the managerial frameworks developed for managing the front end of innovation, which purposefully “wire” the front end of innovation into the strategy and business processes of a firm. The thesis contributes to modern innovation management by connecting the internal and external collaboration networks as foundational elements for successful management of the early phases of innovation processes in a dynamic environment. The innovation capability of a firm is largely defined by its ability to rely on and make use of internal and external collaboration already during the front end activities, which by definition include opportunity identification and analysis, idea generation, profileration and selection, and concept definition. More specifically, coordination of the interfaces between these activities, and between the internal and external innovation environments of a firm is emphasised. The role of information systems, in particular idea management systems, is to support and delineate the innovation-oriented behaviour and interaction of individuals and organizations during front end activities. The findings and frameworks developed in the thesis can be used by companies for purposeful promotion of their front end processes. The thesis provides a systemic strategy framework for managing the front end of innovation – not as a separate process, but as an elemental bundle ofactivities that is closely linked to the overall innovation process and strategy of a firm in a distributed environment. The theoretical contribution of the thesis relies on the advancement of the open innovation paradigm in the strategic context of a firm within its internal and external innovation environments. This thesis applies the constructive research approach and case study methodology to provide theoretically significant results, which are also practically beneficial.

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Mechanisms underlying speciation in plants include detrimental (incompatible) genetic interactions between parental alleles that incur a fitness cost in hybrids. We reported on recessive hybrid incompatibility between an Arabidopsis thaliana strain from Poland, Landsberg erecta (Ler), and many Central Asian A. thaliana strains. The incompatible interaction is determined by a polymorphic cluster of Toll/interleukin-1 receptor-nucleotide binding-leucine rich repeat (TNL) RPP1 (Recognition of Peronospora parasitica1)-like genes in Ler and alleles of the receptor-like kinase Strubbelig Receptor Family 3 (SRF3) in Central Asian strains Kas-2 or Kond, causing temperature-dependent autoimmunity and loss of growth and reproductive fitness. Here, we genetically dissected the RPP1-like Ler locus to determine contributions of individual RPP1-like Ler (R1R8) genes to the incompatibility. In a neutral background, expression of most RPP1-like Ler genes, except R3, has no effect on growth or pathogen resistance. Incompatibility involves increased R3 expression and engineered R3 overexpression in a neutral background induces dwarfism and sterility. However, no individual RPP1-like Ler gene is sufficient for incompatibility between Ler and Kas-2 or Kond, suggesting that co-action of at least two RPP1-like members underlies this epistatic interaction. We find that the RPP1-like Ler haplotype is frequent and occurs with other Ler RPP1-like alleles in a local population in Gorzów Wielkopolski (Poland). Only Gorzów individuals carrying the RPP1-like Ler haplotype are incompatible with Kas-2 and Kond, whereas other RPP1-like alleles in the population are compatible. Therefore, the RPP1-like Ler haplotype has been maintained in genetically different individuals at a single site, allowing exploration of forces shaping the evolution of RPP1-like genes at local and regional population scales.

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Neste Oil has introduced plant oils and animal fats for the production of NExBTL renewable diesel, and these raw materials differ from the conventional mineral based oils. One subject of new raw materials study is thermal degradation, or in another name pyrolysis, of these organic oils and fats. The aim of this master’s thesis is to increase knowledge on thermal degradation of these new raw materials, and to identify possible gaseous harmful thermal degradation compounds. Another aim is to de-termine the health and environmental hazards of identified compounds. One objective is also to examine the formation possibilities of hazardous compounds in the produc-tion of NExBTL-diesel. Plant oils and animal fats consist mostly of triglycerides. Pyrolysis of triglycerides is a complex phenomenon, and many degradation products can be formed. Based on the literature studies, 13 hazardous degradation products were identified, one of which was acrolein. This compound is very toxic and dangerous to the environment. Own pyrolysis experiments were carried out with rapeseed and palm oils, and with a mix-ture of palm oil and animal fat. At least 12 hazardous compounds, including acrolein, were analysed from the gas phase. According to the experiments, the factors which influence on acrolein formation are the time of the experiment, the sphere (air/hydrogen) in which the experiment is carried out, and the characteristics of the used oil. The production of NExBTL-diesel is not based on pyrolysis. This is why thermal degradation is possible only when abnormal process conditions prevail.

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Background Adverse childhood experiences have been described as one of the major environmental risk factors for depressive disorder. Similarly, the deleterious impact of early traumatic experiences on depression seems to be moderated by individual genetic variability. Serotonin transporter (5-HTT) and brain-derived neurotrophic factor (BDNF) modulate the effect of childhood adversity on adult depression, although inconsistencies across studies have been found. Moreover, the gene×environment (G×E) interaction concerning the different types of childhood adversity remains poorly understood. The aim of this study was to analyse the putative interaction between the 5-HTT gene (5-HTTLPR polymorphism), the BDNF gene (Val66Met polymorphism) and childhood adversity in accounting for adult depressive symptoms. Method A sample of 534 healthy individuals filled in self-report questionnaires of depressive symptomatology [the Symptom Check List 90 Revised (SCL-90-R)] and different types of childhood adversities [the Childhood Trauma Questionnaire (CTQ)]. The 5-HTTLPR polymorphism (5-HTT gene) and the Val66Met polymorphism (BDNF gene) were genotyped in the whole sample. Results Total childhood adversity (β=0.27, p<0.001), childhood sexual abuse (CSA; β=0.17, p<0.001), childhood emotional abuse (β=0.27, p<0.001) and childhood emotional neglect (β=0.22, p<0.001) had an impact on adult depressive symptoms. CSA had a greater impact on depressive symptoms in Met allele carriers of the BDNF gene than in the Val/Val group (F=5.87, p<0.0001), and in S carriers of the 5-HTTLPR polymorphism (5-HTT gene) (F=5.80, p<0.0001). Conclusions Childhood adversity per se predicted higher levels of adult depressive symptoms. In addition, BDNF Val66Met and 5-HTTLPR polymorphisms seemed to moderate the effect of CSA on adult depressive symptoms.

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Context. The interaction of microquasar jets with their environment can produce non-thermal radiation as in the case of extragalactic outflows impacting on their surroundings. Significant observational evidence of jet/medium interaction in galactic microquasars has been collected in the past few years, although little theoretical work has been done regarding the resulting non-thermal emission. Aims. In this work, we investigate the non-thermal emission produced in the interaction between microquasar jets and their environment, and the physical conditions for its production. Methods. We developed an analytical model based on those successfully applied to extragalactic sources. The jet is taken to be a supersonic and mildly relativistic hydrodynamical outflow. We focus on the jet/shocked medium structure in its adiabatic phase, and assume that it grows in a self-similar way. We calculate the fluxes and spectra of the radiation produced via synchrotron, inverse Compton, and relativistic bremsstrahlung processes by electrons accelerated in strong shocks. A hydrodynamical simulation is also performed to investigate further the jet interaction with the environment and check the physical parameters used in the analytical model. Results. For reasonable values of the magnetic field, and using typical values of the external matter density, the non-thermal particles could produce significant amounts of radiation at different wavelengths, although they do not cool primarily radiatively, but by adiabatic losses. The physical conditions of the analytical jet/medium interaction model are consistent with those found in the hydrodynamical simulation. Conclusions. Microquasar jet termination regions could be detectable at radio wavelengths for current instruments sensitive to ~arcminute scales. At X-ray energies, the expected luminosities are moderate, although the emitter is more compact than the radio one. The source may be detectable by XMM-Newton or Chandra, with 1-10 arcsec of angular resolution. The radiation at gamma-ray energies may be within the detection limits of the next generation of satellite and ground-based instruments.