Le pergélisol dans les terrains sédimentaires à forte déclivité: distribution, régime thermique et instabilités

Résumé: Dans le contexte d'un climat de plus en plus chaud, la localisation du pergélisol dans les terrains sédimentaires à forte déclivité et l'évaluation des mouvements de terrain qui y ont cours s'avèrent primordiales. S'insérant dans cette problématique, ce travail de thèse s'articule autour de deux axes de recherche différents. D'un point de vue statique, cette recherche propose une étude de la distribution et des caractéristiques du pergélisol dans les éboulis de la zone périglaciaire alpine. D'un point de vue dynamique, une analyse de l'influence des caractéristiques du pergélisol (teneur en glace, température du pergélisol, etc.) et des variations des températures de l'air et du sol sur les vitesses de fluage des corps sédimentaires gelés est effectuée. Afin de répondre à ce double objectif, l'approche "terrain" a été privilégiée. Pour déterminer la répartition et les caractéristiques du pergélisol, les méthodes traditionnelles de prospection du pergélisol ont été utilisées, à savoir la mesure de la température du sol à la base du manteau neigeux (BTS), la mesure de la température du sol en continu ainsi que la méthode géoélectrique. Les mouvements de terrain ont pour leur part été mesurés à l'aide d'un GPS différentiel. L'étude de la distribution du pergélisol a été effectuée dans une quinzaine d'éboulis situés dans les régions du Mont Gelé (Verbier-Nendaz) et d'Arolla principalement. Dans la plupart des cas, un pergélisol a pu être mis en évidence dans la partie inférieure des accumulations sédimentaires, alors que la partie médiane des éboulis n'est, le plus souvent, pas gelée. Si cette absence de pergélisol se prolonge parfois dans les portions sommitales des pentes, les mesures réalisées montrent que dans d'autres cas des sédiments gelés y sont à nouveau présents. Les résistivités électriques mesurées dans les portions gelées des éboulis étudiés sont dans la plupart des cas nettement inférieures à celles mesurées sur les glaciers rocheux. Des études préalables ont montré que des circulations d'air internes sont responsables de l'anomalie thermique négative et, lorsqu'il existe, du pergélisol que l'on trouve dans la partie inférieure d'éboulis situés plus de 1000 m plus bas que la limite inférieure régionale du pergélisol discontinu. L'étude de quatre sites de basse altitude (1400-1900 m), et notamment l'équipement du site de Dreveneuse (Préalpes Valaisannes) avec deux forages, des capteurs de température de surface et un anémomètre a permis de vérifier et de préciser le mécanisme de ventilation actif au sein des éboulis froids de basse altitude. Ce mécanisme fonctionne de la manière suivante: en hiver, l'air contenu dans l'éboulis, plus chaud et plus léger que l'air extérieur, monte à l'intérieur de l'accumulation sédimentaire et est expulsé dans ses parties sommitales. Cet effet de cheminée provoque une aspiration d'air froid à l'intérieur de la partie inférieure de l'éboulis, causant ainsi un sur-refroidissement marqué du terrain. En été, le mécanisme s'inverse, l'éboulis étant plus froid que l'air environnant. De l'air froid est alors expulsé au bas de la pente. Une ventilation ascendante hivernale a pu être mise en évidence dans certains des éboulis de haute altitude étudiés. Elle est probablement en grande partie responsable de la configuration particulière des zones gelées observées. Même si l'existence d'un effet de cheminée n'a pu être démontrée dans tous les cas, du fait notamment de la glace interstitielle qui entrave le cheminement de l'air, des indices laissant présager son possible fonctionnement existent dans la quasi totalité des éboulis étudiés. L'absence de pergélisol à des altitudes qui lui sont favorables pourrait en tous les cas s'expliquer par un réchauffement du terrain lié à des expulsions d'air relativement chaud. L'étude des mouvements de terrain a été effectuée sur une dizaine de sites, principalement sur des glaciers rocheux, mais également sur une moraine de poussée et - II - Résumé ? abstract quelques éboulis. Plusieurs glaciers rocheux présentent des formes de déstabilisation récente (niches d'arrachement, blocs basculés, apparition de la matrice fine à la surface, etc.), ce qui témoigne d'une récente accélération des vitesses de déplacement. Ce phénomène, qui semble général à l'échelle alpine, est probablement à mettre sur le compte du réchauffement du pergélisol depuis une vingtaine d'années. Les vitesses mesurées sur ces formations sont souvent plus élevées que les valeurs habituellement proposées dans la littérature. On note par ailleurs une forte variabilité inter-annuelle des vitesses, qui semblent dépendre de la variation de la température moyenne annuelle de surface. Abstract: In the context of a warmer climate, the localisation of permafrost in steep sedimentary terrain and the measurement of terrain movements that occur in these areas is of great importance. With respect to these problems, this PhD thesis follows two different research axes. From a static point of view, the research presents a study of the permafrost distribution and characteristics in the talus slopes of the alpine periglacial belt. From a dynamic point of view, an analysis of the influence of the permafrost characteristics (ice content, permafrost temperature, etc.) and air and soil temperature variations on the creep velocities of frozen sedimentary bodies is carried out. In order to attain this double objective, the "field" approach was favoured. To determine the distribution and the characteristics of permafrost, the traditional methods of permafrost prospecting were used, i.e. ground surface temperature measurements at the base of the snow cover (BTS), year-round ground temperature measurements and DC-resistivity prospecting. The terrain movements were measured using a differential GPS. The permafrost distribution study was carried out on 15 talus slopes located mainly in the Mont Gelé (Verbier-Nendaz) and Arolla areas (Swiss Alps). In most cases, permafrost was found in the lower part of the talus slope, whereas the medium part was free of ice. In some cases, the upper part of the talus is also free of permafrost, whereas in other cases permafrost is present. Electrical resistivities measured in the frozen parts of the studied talus are in most cases clearly lower than those measured on rock glaciers. Former studies have shown that internal air circulation is responsible for the negative thermal anomaly and, when it exists, the permafrost present in the lower part of talus slopes located more than 1000 m below the regional lower limit of discontinuous permafrost. The study of four low-altitude talus slopes (1400-1900 m), and notably the equipment of Dreveneuse field site (Valais Prealps) with two boreholes, surface temperature sensors and an anemometer permitted to verify and to detail the ventilation mechanism active in low altitude talus slopes. This mechanism works in the following way: in winter, the air contained in the block accumulation is warmer and lighter than the surrounding air and therefore moves upward in the talus and is expelled in its upper part. This chimney effect induces an aspiration of cold air in the interior of the lower part of talus, that causes a strong overcooling of the ground. In summer, the mechanism is reversed because the talus slope is colder than the surrounding air. Cold air is then expelled in the lower part of the slope. Evidence of ascending ventilation in wintertime could also be found in some of the studied high-altitude talus slopes. It is probably mainly responsible for the particular configuration of the observed frozen areas. Even if the existence of a chimney effect could not be demonstrated in all cases, notably because of interstitial ice that obstructs Résumé ? abstract - III - the air circulation, indices of its presence exist in nearly all the studied talus. The absence of permafrost at altitudes favourable to its presence could be explained, for example, by the terrain warming caused by expulsion of relatively warm air. Terrain movements were measured at about ten sites, mainly on rock glaciers, but also on a push moraine and some talus slopes. Field observations reveal that many rock glaciers display recent destabilization features (landslide scars, tilted blocks, presence of fine grained sediments at the surface, etc.) that indicate a probable recent acceleration of the creep velocities. This phenomenon, which seems to be widespread at the alpine scale, is probably linked to the permafrost warming during the last decades. The measured velocities are often higher than values usually proposed in the literature. In addition, strong inter-annual variations of the velocities were observed, which seems to depend on the mean annual ground temperature variations.

Database Rights in Safe European Home: The Path to More Rigorous Protection of Information

1. Introduction "The one that has compiled ... a database, the collection, securing the validity or presentation of which has required an essential investment, has the sole right to control the content over the whole work or over either a qualitatively or quantitatively substantial part of the work both by means of reproduction and by making them available to the public", Finnish Copyright Act, section 49.1 These are the laconic words that implemented the much-awaited and hotly debated European Community Directive on the legal protection of databases,2 the EDD, into Finnish Copyright legislation in 1998. Now in the year 2005, after more than half a decade of the domestic implementation it is yet uncertain as to the proper meaning and construction of the convoluted qualitative criteria the current legislation employs as a prerequisite for the database protection both in Finland and within the European Union. Further, this opaque Pan-European instrument has the potential of bringing about a number of far-reaching economic and cultural ramifications, which have remained largely uncharted or unobserved. Thus the task of understanding this particular and currently peculiarly European new intellectual property regime is twofold: first, to understand the mechanics and functioning of the EDD and second, to realise the potential and risks inherent in the new legislation in economic, cultural and societal dimensions. 2. Subject-matter of the study: basic issues The first part of the task mentioned above is straightforward: questions such as what is meant by the key concepts triggering the functioning of the EDD such as presentation of independent information, what constitutes an essential investment in acquiring data and when the reproduction of a given database reaches either qualitatively or quantitatively the threshold of substantiality before the right-holder of a database can avail himself of the remedies provided by the statutory framework remain unclear and call for a careful analysis. As for second task, it is already obvious that the practical importance of the legal protection providedby the database right is in the rapid increase. The accelerating transformationof information into digital form is an existing fact, not merely a reflection of a shape of things to come in the future. To take a simple example, the digitisation of a map, traditionally in paper format and protected by copyright, can provide the consumer a markedly easier and faster access to the wanted material and the price can be, depending on the current state of the marketplace, cheaper than that of the traditional form or even free by means of public lending libraries providing access to the information online. This also renders it possible for authors and publishers to make available and sell their products to markedly larger, international markets while the production and distribution costs can be kept at minimum due to the new electronic production, marketing and distributionmechanisms to mention a few. The troublesome side is for authors and publishers the vastly enhanced potential for illegal copying by electronic means, producing numerous virtually identical copies at speed. The fear of illegal copying canlead to stark technical protection that in turn can dampen down the demand for information goods and services and furthermore, efficiently hamper the right of access to the materials available lawfully in electronic form and thus weaken the possibility of access to information, education and the cultural heritage of anation or nations, a condition precedent for a functioning democracy. 3. Particular issues in Digital Economy and Information Networks All what is said above applies a fortiori to the databases. As a result of the ubiquity of the Internet and the pending breakthrough of Mobile Internet, peer-to-peer Networks, Localand Wide Local Area Networks, a rapidly increasing amount of information not protected by traditional copyright, such as various lists, catalogues and tables,3previously protected partially by the old section 49 of the Finnish Copyright act are available free or for consideration in the Internet, and by the same token importantly, numerous databases are collected in order to enable the marketing, tendering and selling products and services in above mentioned networks. Databases and the information embedded therein constitutes a pivotal element in virtually any commercial operation including product and service development, scientific research and education. A poignant but not instantaneously an obvious example of this is a database consisting of physical coordinates of a certain selected group of customers for marketing purposes through cellular phones, laptops and several handheld or vehicle-based devices connected online. These practical needs call for answer to a plethora of questions already outlined above: Has thecollection and securing the validity of this information required an essential input? What qualifies as a quantitatively or qualitatively significant investment? According to the Directive, the database comprises works, information and other independent materials, which are arranged in systematic or methodical way andare individually accessible by electronic or other means. Under what circumstances then, are the materials regarded as arranged in systematic or methodical way? Only when the protected elements of a database are established, the question concerning the scope of protection becomes acute. In digital context, the traditional notions of reproduction and making available to the public of digital materials seem to fit ill or lead into interpretations that are at variance with analogous domain as regards the lawful and illegal uses of information. This may well interfere with or rework the way in which the commercial and other operators have to establish themselves and function in the existing value networks of information products and services. 4. International sphere After the expiry of the implementation period for the European Community Directive on legal protection of databases, the goals of the Directive must have been consolidated into the domestic legislations of the current twenty-five Member States within the European Union. On one hand, these fundamental questions readily imply that the problemsrelated to correct construction of the Directive underlying the domestic legislation transpire the national boundaries. On the other hand, the disputes arisingon account of the implementation and interpretation of the Directive on the European level attract significance domestically. Consequently, the guidelines on correct interpretation of the Directive importing the practical, business-oriented solutions may well have application on European level. This underlines the exigency for a thorough analysis on the implications of the meaning and potential scope of Database protection in Finland and the European Union. This position hasto be contrasted with the larger, international sphere, which in early 2005 does differ markedly from European Union stance, directly having a negative effect on international trade particularly in digital content. A particular case in point is the USA, a database producer primus inter pares, not at least yet having aSui Generis database regime or its kin, while both the political and academic discourse on the matter abounds. 5. The objectives of the study The above mentioned background with its several open issues calls for the detailed study of thefollowing questions: -What is a database-at-law and when is a database protected by intellectual property rights, particularly by the European database regime?What is the international situation? -How is a database protected and what is its relation with other intellectual property regimes, particularly in the Digital context? -The opportunities and threats provided by current protection to creators, users and the society as a whole, including the commercial and cultural implications? -The difficult question on relation of the Database protection and protection of factual information as such. 6. Dsiposition The Study, in purporting to analyse and cast light on the questions above, is divided into three mainparts. The first part has the purpose of introducing the political and rationalbackground and subsequent legislative evolution path of the European database protection, reflected against the international backdrop on the issue. An introduction to databases, originally a vehicle of modern computing and information andcommunication technology, is also incorporated. The second part sets out the chosen and existing two-tier model of the database protection, reviewing both itscopyright and Sui Generis right facets in detail together with the emergent application of the machinery in real-life societal and particularly commercial context. Furthermore, a general outline of copyright, relevant in context of copyright databases is provided. For purposes of further comparison, a chapter on the precursor of Sui Generi, database right, the Nordic catalogue rule also ensues. The third and final part analyses the positive and negative impact of the database protection system and attempts to scrutinize the implications further in the future with some caveats and tentative recommendations, in particular as regards the convoluted issue concerning the IPR protection of information per se, a new tenet in the domain of copyright and related rights.

Guidelines for irrigation scheduling of banana crop in São Francisco Valley, Brazil. I - Root distribution and activity

In order to establish guidelines for irrigation water management of banana cv. Pacovan (AAB group, Prata sub-group) in Petrolina County, northeastern Brazil, the root distribution and activity were measured on an irrigated plantation, in a medium texture soil, with plants spaced in a 3 x 3 m grid. Root distribution was evaluated by the soil profile method aided by digital image analysis, while root activity was indirectly determined by the changing of soil water content and by the direction of soil water flux. Data were collected since planting in January 1999 to the 3rd harvest in September 2001. Effective rooting depth increased from 0.4 m at 91 days after planting (dap), to 0.6 m at 370, 510, and 903 dap, while water absorption by roots was predominantly in the top 0,6 m.

Content value chains modelling using a copyright ontology

Existing digital rights management (DRM) systems, initiatives like Creative Commons or research works as some digital rights ontologies provide limited support for content value chains modelling and management. This is becoming a critical issue as content markets start to profit from the possibilities of digital networks and the World Wide Web. The objective is to support the whole copyrighted content value chain across enterprise or business niches boundaries. Our proposal provides a framework that accommodates copyright law and a rich creation model in order to cope with all the creation life cycle stages. The dynamic aspects of value chains are modelled using a hybrid approach that combines ontology-based and rule-based mechanisms. The ontology implementation is based on Web Ontology Language and Description Logic (OWL-DL) reasoners, are directly used for license checking. On the other hand, for more complex aspects of the dynamics of content value chains, rule languages are the choice.

Älykäs sisältötuote monimediaympäristössä, case: AVO

Diplomityön teoriaosassa tutkittiin monimedian jakelukanavia ja niiden ominaisuuksia sisältöpalveluissa. Työssä esiteltiin keinoja älykkyyden lisäämiseksi monnimediasisältötuotannossa sekä tarkasteltiin sisältöpalvelujen käytettävyyttä. Työssä keskityttiin neuroverkkoteknologiaan, sen toteuttamiseen sekä ohjelmisto-agentteihin. Empiirisessä osassa tutustuttiin työministeriön AVO-ammatinvalintaohjelman toimintaan. Työssä määriteltiin Excel-taulukkoon 280 ammatin ominaisuudet, jotka pohjautuivat AVO:n 122 kysymykseen. Työministeriöstä on saatu 5115 henkilön vastaukset AVO-ammatinvalintaohjelman kysymyksiin. Tätä vastausaineistoa ja tutkimuksessa laadittua ammattitaulukkoa käytettiin neuroverkon opettamiseen. Lopuksi analysoitiin SOM-karttoja. Analyysin tarkoituksena oli tutkia laaditun ammattitaulukon oikeellisuutta ja eri ammattien sijoittumista SOM-kartalle. Tutkimus osoitti, että neuroverkkoteknologia soveltuisi uuden urasuunnittelupalvelun ydinteknologiaksi.

IP Multicast in Future Mobile Networks

Erilaisten IP-pohjaisten palvelujen käyttö lisääntyy jatkuvasti samalla, kun käyttäjistä tulee yhä liikkuvaisempia. Tästä syystä IP- protokolla tulee väistämättä myös mobiiliverkkoihin. Tässä diplomityössä tutkitaan mobiliteetin IP multcastingiin tuomia ongelmia ja simuloidaan niitä Network Simulatoria käyttäen. Pääpaino on ongelmalla, joka aiheutuu multicast- ryhmänmuodostusviiveestä. Tätä ongelmaa simuloidaan, jotta viiveen, mobiilikäyttäjien palveluunsaapumistaajuuden ja Scalable Reliable Multicast (SRM) protokollan ajastinarvojen asetusten vaikutus repair request- pakettien määrään ja sitä kautta suoritettavien uudelleenlähetysten määrään selviäisi. Eri parametrien vaikutuksen tutkimiseksi esitetään simulaatiotuloksia varioiduilla parametreillä käyttäen CDF- käyriä. Tulosten perusteella merkittävin tekijä uudelleenlähetyspyyntöjen kannalta on protokollan ajastimien arvot ja haluttu palvelun taso, viiveen merkityksen jäädessä vähäiseksi. Työn lopuksi tutkitaan SRM- protokollan soveltuvuutta mobiiliverkkoihin ja pohditaan vaihtoehtoja toiminnan parantamiseksi.

XML-based content transformation in converged service development

Tele- ja dataviestinnän yhdistyminen digitaaliseen sisältöön luo uusia palveluideoita sekä mobiili- että internetverkkoihin. Nämä palvelut kehitetään usein erikseen, jolloin saman sisällön käyttäminen eri pääsymenetelmin ei ole mahdollista. Sisältömuunnos on mahdollista sisällön ja muotoilun eriyttämisellä, joka puolestaan vaatii informaatioyksiköiden merkkauksen sisältöä kuvaavilla lisätiedoilla. Tässä diplomityössä tutkitaan Extensible Markup Languagen (XML) käyttöä yhdistyneiden palvelujen sisältömuunnoksessa. Nykyisiä ja tulevia palveluita ja verkkoja tarkastellaan sekä sisällön että liiketoiminnan kannalta. Lisäksi esitellään lyhyesti omia ajatuksia ja käsityksiä yhdistyneistä palveluista ja informaation täsmällisyydestä. Työn käytännön osuudessa kuvataan itse suunniteltu palvelualusta sekä esitellään sen avulla rakennettuja sovelluksia

Delivery system for location based information in wireless IP networks

Tämä työ esittelee uuden tarjota paikasta riippuvaa tietoa langattomien tietoverkkojen käyttäjille. Tieto välitetään jokaiselle käyttäjälle tietämättä mitään käyttäjän henkilöllisyydestä. Sovellustason protokollaksi valittiin HTTP, joka mahdollistaa tämän järjestelmän saattaa tietoa perille useimmille käyttäjille, jotka käyttävät hyvinkin erilaisia päätelaitteita. Tämä järjestelmä toimii sieppaavan www-liikenteen välityspalvelimen jatkeena. Erilaisten tietokantojen sisällä on perusteella järjestelmä päättää välitetäänkö tietoa vai ei. Järjestelmä sisältää myös yksinkertaisen ohjelmiston käyttäjien paikantamiseksi yksittäisen tukiaseman tarkkuudella. Vaikka esitetty ratkaisu tähtääkin paikkaan perustuvien mainosten tarjoamiseen, se on helposti muunnettavissa minkä tahansa tyyppisen tiedon välittämiseen käyttäjille.

Nature of the Epidemic Threshold for the Susceptible-Infected-Susceptible Dynamics in Networks

We develop an analytical approach to the susceptible-infected-susceptible epidemic model that allows us to unravel the true origin of the absence of an epidemic threshold in heterogeneous networks. We find that a delicate balance between the number of high degree nodes in the network and the topological distance between them dictates the existence or absence of such a threshold. In particular, small-world random networks with a degree distribution decaying slower than an exponential have a vanishing epidemic threshold in the thermodynamic limit.

Beyond contact-based transmission networks: the role of spatial coincidence.

Animal societies rely on interactions between group members to effectively communicate and coordinate their actions. To date, the transmission properties of interaction networks formed by direct physical contacts have been extensively studied for many animal societies and in all cases found to inhibit spreading. Such direct interactions do not, however, represent the only viable pathways. When spreading agents can persist in the environment, indirect transmission via 'same-place, different-time' spatial coincidences becomes possible. Previous studies have neglected these indirect pathways and their role in transmission. Here, we use rock ant colonies, a model social species whose flat nest geometry, coupled with individually tagged workers, allowed us to build temporally and spatially explicit interaction networks in which edges represent either direct physical contacts or indirect spatial coincidences. We show how the addition of indirect pathways allows the network to enhance or inhibit the spreading of different types of agent. This dual-functionality arises from an interplay between the interaction-strength distribution generated by the ants' movement and environmental decay characteristics of the spreading agent. These findings offer a general mechanism for understanding how interaction patterns might be tuned in animal societies to control the simultaneous transmission of harmful and beneficial agents.

The Spatial Distribution of Spanish Transport Infrastructure between 1860 and 1930

The origin of Spanish regional economic divergence can be traced back at least until the seventeenth century, although its full definition took place during industrialisation. Historians have often included uneven regional infrastructure endowments among the factors that explain divergence among Spanish regions, although no systematic analysis of the spatial distribution of Spanish infrastructure and its determinants has been carried out so far. This paper aims at filling that gap, by offering a description of the regional distribution of the main Spanish transport infrastructure between the middle of the nineteenth century and the Civil War. In addition, it estimates a panel data model to search into the main reasons that explain the differences among the Spanish regional endowments of railways and roads during that period. The outcomes of that analysis indicate that both institutional factors and the physical characteristics of each area had a strong influence on the distribution of transport infrastructure among the Spanish regions.

On Option Price Information Content and Extraction of Implied Probability Distributions

In this study we used market settlement prices of European call options on stock index futures to extract implied probability distribution function (PDF). The method used produces a PDF of returns of an underlying asset at expiration date from implied volatility smile. With this method, the assumption of lognormal distribution (Black-Scholes model) is tested. The market view of the asset price dynamics can then be used for various purposes (hedging, speculation). We used the so called smoothing approach for implied PDF extraction presented by Shimko (1993). In our analysis we obtained implied volatility smiles from index futures markets (S&P 500 and DAX indices) and standardized them. The method introduced by Breeden and Litzenberger (1978) was then used on PDF extraction. The results show significant deviations from the assumption of lognormal returns for S&P500 options while DAX options mostly fit the lognormal distribution. A deviant subjective view of PDF can be used to form a strategy as discussed in the last section.

Networks of noisy oscillators with correlated degree and frequency dispersion

We investigate how correlations between the diversity of the connectivity of networks and the dynamics at their nodes affect the macroscopic behavior. In particular, we study the synchronization transition of coupled stochastic phase oscillators that represent the node dynamics. Crucially in our work, the variability in the number of connections of the nodes is correlated with the width of the frequency distribution of the oscillators. By numerical simulations on Erdös-Rényi networks, where the frequencies of the oscillators are Gaussian distributed, we make the counterintuitive observation that an increase in the strength of the correlation is accompanied by an increase in the critical coupling strength for the onset of synchronization. We further observe that the critical coupling can solely depend on the average number of connections or even completely lose its dependence on the network connectivity. Only beyond this state, a weighted mean-field approximation breaks down. If noise is present, the correlations have to be stronger to yield similar observations.

Tissue distribution of retinoids in common dolphins (Delphinus delphis).

Exposure to organochlorines induces retinoid deficiency in mammals; hence, retinoids are potential biomarkers of the impact of these pollutants. Appropriate target tissues to monitor retinoids in cetaceans have not been properly identified because of a lack of information on the contribution of each tissue to total body retinoids. Therefore, we have addressed this issue by studying the contribution of the main body tissues to retinoids in 21 common dolphins obtained from incidental catches and in apparent good health and nutritive condition. Although concentrations in the liver were highest, those in blubber were also high and accounted for 43% of the total retinoid load of the compartments examined. As blubber can be obtained using non-invasive biopsy techniques, this tissue is proposed as a reliable indicator of retinoid status in cetaceans. However, blubber topographical variation in structure and composition requires standardization of sampling sites. Retinoid concentrations did not differ significantly between sexes or with body size for any of the tissues, but the lipid content of blubber strongly influenced these concentrations. Biopsies from healthy, free-ranging individuals are preferred to samples from stranded animals. Further research on the influence of factors (age, sex, reproductive condition, diet) that potentially affect retinoid levels is required to implement the use of retinoids as biomarkers of pollutant exposure in cetaceans.

Inter organizational learning within and by innovation networks

The thesis deals with the phenomenon of learning between organizations in innovation networks that develop new products, services or processes. Inter organizational learning is studied especially at the level of the network. The role of the network can be seen as twofold: either the network is a context for inter organizational learning, if the learner is something else than the network (organization, group, individual), or the network itself is the learner. Innovations are regarded as a primary source of competitiveness and renewal in organizations. Networking has become increasingly common particularly because of the possibility to extend the resource base of the organization through partnerships and to concentrate on core competencies. Especially in innovation activities, networks provide the possibility to answer the complex needs of the customers faster and to share the costs and risks of the development work. Networked innovation activities are often organized in practice as distributed virtual teams, either within one organization or as cross organizational co operation. The role of technology is considered in the research mainly as an enabling tool for collaboration and learning. Learning has been recognized as one important collaborative process in networks or as a motivation for networking. It is even more important in the innovation context as an enabler of renewal, since the essence of the innovation process is creating new knowledge, processes, products and services. The thesis aims at providing enhanced understanding about the inter organizational learning phenomenon in and by innovation networks, especially concentrating on the network level. The perspectives used in the research are the theoretical viewpoints and concepts, challenges, and solutions for learning. The methods used in the study are literature reviews and empirical research carried out with semi structured interviews analyzed with qualitative content analysis. The empirical research concentrates on two different areas, firstly on the theoretical approaches to learning that are relevant to innovation networks, secondly on learning in virtual innovation teams. As a result, the research identifies insights and implications for learning in innovation networks from several viewpoints on organizational learning. Using multiple perspectives allows drawing a many sided picture of the learning phenomenon that is valuable because of the versatility and complexity of situations and challenges of learning in the context of innovation and networks. The research results also show some of the challenges of learning and possible solutions for supporting especially network level learning.