63 resultados para Host Relationships


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Measles, caused by measles virus (MV), is a highly contagious viral disease causing severe respiratory infection and a typical rash. Despite the availability of a protective vaccine, measles is still the leading vaccine-preventable cause of childhood mortality worldwide. The high mortality associated with the disease is mainly due to an increased susceptibility to secondary infections during the period of immunosuppression that continues for several weeks after recovery. The present study was undertaken to elucidate the role of cytoskeletal components in the regulation of MV infection. The most interesting finding was that MV replication was activated in unstimulated peripheral blood mononuclear cells (PBMC) when globular actin was converted into the filamentous form with jasplakinolide. This provides a new aspect in our understanding of MV infection in PBMC. In the second part of the thesis we investigated MV-induced structural changes of cellular nuclear matrix, which is a proteinaceous framework of the nucleus similar to the cytoskeleton in the cytoplasm. We showed that cleavage of nuclear markers was virusspecific and a general caspase inhibitor rescued MV-infected cells from cell death. Furthermore, we studied MV-induced innate immune mechanisms in lung epithelial and endothelial cells. Our results showed that MV infection resulted in activation of the double stranded RNA (dsRNA) binding molecules melanoma differentiation-associated gene 5 (mda-5), retinoic acid inducible gene I (RIG-I), and toll-like receptor 3 (TLR3) gene expression, followed by high expression of antiviral cytokine mRNA.

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This thesis examines the supplier-buyer relationships in the Finnish electronics industry. The aim of the study was to increase understanding on the challenges that suppliers face in their relationship with the buyer. The research was conducted using qualitative methods because they allow more perspective for the research problem than quantitative methods would have. Choosing qualitative method also affected the selection of a research technique. Analysis of secondary data from written documents was chosen to give more perspective to a broad problem. The main findings of this research are that the relationships between supplier and buyer in electronics industry are challenging because supplier must understand and face three types of challenges. The challenges are: understanding the environment, choosing and implementing correct strategy and managing relationships. For the supplier it is important to understand the environment so it can adjust own strategy to fit to the environment. The supplier should also be careful not to be too dependent on the buyer.

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Trust in inter-organizational collaborative relationships has attracted substantial research interest among academics and practitioners. Previous studies have concentrated on the benefits of trust to business outcomes and economic performance, as it is considered to be a source of competitive advantage. Despite this increased level of interest, there is no consensus, much less overall agreement, about how it should be conceptualized or about the number of dimensions it incorporates. On the inter-organizational level there is an obvious challenge in defining both the trusting party and the objects of trust. Thus, the notion of trust as an under-theorized and poorly understood phenomenon still holds. Hence, the motivation of this study was fuelled by the need to increase our knowledge and understanding of the role and nature of trust in inter-organizational collaborative relationships. It is posited that there is a call for more understanding about its antecedents and consequences, as well as about the very concept in inter-organizational collaborative relationships. The study is divided into two parts. The first part gives a general overview, and the second part comprises four research publications. Both qualitative and quantitative research methodology is utilized. A multi-method research design was used because it provides different levels of data and different perspectives on the phenomenon. The results of this study reveal that trust incorporates three dimensions on both the individual and the organizational level: capability, goodwill, and self-reference. Trust develops from the reputation and behavior of the trusted party. It appears from this study that trust is clearly directed towards both individual boundary spanners and the counterpart company itself – i.e. not only to one or the other. The trusting party, on the other hand, is always an individual, and not the organization per se. Trust increases collaboration benefits and lowers collaboration drawbacks, thus having a positive effect on relationship performance. The major contribution of this study lies in uncovering the critical points and drawbacks in prior research and thereby in responding to the highlighted challenges. The way in which these challenges were addressed offers contributions to three major issues in the emerging theory of trust in the inter-organizational context: firstly, this study clarifies the trustor-trustee discussion; secondly, it conceptualizes trust as existing on both individual and organizational levels; and thirdly, it provides more information about the antecedents of trust and the ways in which it affects relationship performance.

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In nature, variation for example in herbivory, wind exposure, moisture and pollution impact often creates variation in physiological stress and plant productivity. This variation is seldom clear-cut, but rather results in clines of decreasing growth and productivity towards the high-stress end. These clines of unidirectionally changing stress are generally known as ‘stress gradients’. Through its effect on plant performance, stress has the capacity to fundamentally alter the ecological relationships between individuals, and through variation in survival and reproduction it also causes evolutionary change, i.e. local adaptations to stress and eventually speciation. In certain conditions local adaptations to environmental stress have been documented in a matter of just a few generations. In plant-plant interactions, intensities of both negative interactions (competition) and positive ones (facilitation) are expected to vary along stress gradients. The stress-gradient hypothesis (SGH) suggests that net facilitation will be strongest in conditions of high biotic and abiotic stress, while a more recent ‘humpback’ model predicts strongest net facilitation at intermediate levels of stress. Plant interactions on stress gradients, however, are affected by a multitude of confounding factors, making studies of facilitation-related theories challenging. Among these factors are plant ontogeny, spatial scale, and local adaptation to stress. The last of these has very rarely been included in facilitation studies, despite the potential co-occurrence of local adaptations and changes in net facilitation in stress gradients. Current theory would predict both competitive effects and facilitative responses to be weakest in populations locally adapted to withstand high abiotic stress. This thesis is based on six experiments, conducted both in greenhouses and in the field in Russia, Norway and Finland, with mountain birch (Betula pubescens subsp. czerepanovii) as the model species. The aims were to study potential local adaptations in multiple stress gradients (both natural and anthropogenic), changes in plant-plant interactions under conditions of varying stress (as predicted by SGH), potential mechanisms behind intraspecific facilitation, and factors confounding plant-plant facilitation, such as spatiotemporal, ontogenetic, and genetic differences. I found rapid evolutionary adaptations (occurring within a time-span of 60 to 70 years) towards heavy-metal resistance around two copper-nickel smelters, a phenomenon that has resulted in a trade-off of decreased performance in pristine conditions. Heavy-metal-adapted individuals had lowered nickel uptake, indicating a possible mechanism behind the detected resistance. Seedlings adapted to heavy-metal toxicity were not co-resistant to others forms of abiotic stress, but showed co-resistance to biotic stress by being consumed to a lesser extent by insect herbivores. Conversely, populations from conditions of high natural stress (wind, drought etc.) showed no local adaptations, despite much longer evolutionary time scales. Due to decreasing emissions, I was unable to test SGH in the pollution gradients. In natural stress gradients, however, plant performance was in accordance with SGH, with the strongest host-seedling facilitation found at the high-stress sites in two different stress gradients. Factors confounding this pattern included (1) plant size / ontogenetic status, with seedling-seedling interactions being competition dominated and host-seedling interactions potentially switching towards competition with seedling growth, and (2) spatial distance, with competition dominating at very short planting distances, and facilitation being strongest at a distance of circa ¼ benefactor height. I found no evidence for changes in facilitation with respect to the evolutionary histories of plant populations. Despite the support for SGH, it may be that the ‘humpback’ model is more relevant when the main stressor is resource-related, while what I studied were the effects of ‘non-resource’ stressors (i.e. heavy-metal pollution and wind). The results have potential practical applications: the utilisation of locally adapted seedlings and plant facilitation may increase the success of future restoration efforts in industrial barrens as well as in other wind-exposed sites. The findings also have implications with regard to the effects of global change in subarctic environments: the documented potential by mountain birch for rapid evolutionary change, together with the general lack of evolutionary ‘dead ends’, due to not (over)specialising to current natural conditions, increase the chances of this crucial forest-forming tree persisting even under the anticipated climate change.

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In this dissertation, Active Galactic Nuclei (AGN) and their host galaxies are discussed. Together with transitional events, such as supernovae and gamma-ray bursts, AGN are the most energetic phenomena in the Universe. The dominant fraction of their luminosity originates from the center of a galaxy, where accreting gas falls into a supermassive black hole, converting gravitational energy to radiation. AGN have a wide range of observed properties: e.g. in their emission lines, radio emission, and variability. Most likely, these properties depend significantly on their orientation to our line-of-sight, and to unify AGN into physical classes it is crucial to observe their orientation-independent properties, such as the host galaxies. Furthermore, host galaxy studies are essential to understand the formation and co-evolution of galactic bulges and supermassive black holes. In this thesis, the main focus is on observationally characterizing AGN host galaxies using optical and near-infrared imaging and spectroscopy. BL Lac objects are a class of AGN characterized by rapidly variable and polarized continuum emission across the electromagnetic spectrum, and coredominated radio emission. The near-infrared properties of intermediate redshift BL Lac host galaxies are studied in Paper I. They are found to be large elliptical galaxies that are more luminous than their low redshift counterparts suggesting a strong luminosity evolution, and a contribution from a recent star formation episode. To analyze the stellar content of galaxies in more detail multicolor data, especially observations at blue wavelengths, are essential. In Paper III, optical - near-infrared colors and color gradients are derived for low redshift BL Lac host galaxies. They show bluer colors and steeper color gradients than inactive ellipticals which, most likely, are caused by a relatively young stellar population indicating a different evolutionary stage between AGN hosts and inactive ellipticals. In Paper II, near-infrared imaging of intermediate redshift radio-quiet quasar hosts is used to study their luminosity evolution. The hosts are large elliptical galaxies, but they are systematically fainter than the hosts of radio-loud quasars at similar redshifts, suggesting a link between the luminosity of the host galaxies and the radio properties of AGN. In Paper IV, the characteristics of near-infrared stellar absorption features of low redshift radio galaxies are compared with those of inactive early-type galaxies. The comparison suggests that early-type galaxies with AGN are in a different evolutionary stage than their inactive counterparts. Moreover, radio galaxies are found to contain stellar populations containing both old and intermediate age components.

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Previous studies of the local involvement of multinational corporation (MNC) subsidiaries focus on host-country firms and local business partners such as suppliers and customers. The role of host-country universities in the same context of innovation networks is neglected. Furthermore, there are many organizational culture- and knowledge-related differences between universities and companies, and this is likely to pose additional challenges for successful collaboration. Early university-industry (U-I) studies have primarily been limited within a national boundary, being concerned with a single level of culture (i.e., at an organizational level) and one-way knowledge transfer from university to industry. Research on more dynamic knowledge interaction in multinational settings is lacking. This is particularly true in the business context of China. In today’s globalizing and rapidly changing organizations, addressing cultural differences and clashes is an everyday reality, and inter-cultural U-I collaboration is becoming a key asset for gaining global competitiveness. This study deals with Finnish MNC subsidiaries’ research collaboration with Chinese universities. It aims to explore the essence of such U-I collaboration and knowledge interaction, uncovering the deep functioning mechanisms of culture underlying effective collaborative knowledge creation and innovation. The study reviews critically different bodies of literature including knowledge management theories and studies, U-I collaboration and knowledge interaction, and cross-cultural research in terms of organizational knowledge generation and utilization. It adopts a case study strategy with qualitative research methods, and data is collected through in-depth interviews and participant observation. The study presents the following major findings: 1. In the light of a comprehensive analysis of U-I collaboration, an effective matching strategy is proposed, in the assumption that good alignment of knowledge interaction strategies and approaches with their corresponding knowledge type, capability development and research task may greatly enhance the effectiveness of cross-cultural U-I collaboration and knowledge interaction. 2. It is proposed that in the Chinese MNC context more dynamic types of knowledge interaction like knowledge co-creation should be of key concern particularly when dealing simultaneously with multi-disciplinary applied research of human factors and technologies. U-I knowledge interaction, otherwise, pays attention only to the study of one-way technology and knowledge transfer. 3. It is posited that the influence of culture on collaborative knowledge interaction can be studied in a valuable way when knowledge-related variables are simultaneously taken into account. A systematic analysis of the role of knowledge in cross-cultural knowledge interaction could best be approached from multi-aspects of knowledge including not only nature, characteristics and types of knowledge but also the process of knowledge (e.g., intensifications of knowledge interaction). 4. The study demonstrates the significant role of aspects of the host-country culture (e.g., Chinese guanxi) in U-I collaboration and knowledge interaction. This is evident, for instance, in issues related to interpersonal relationships and trust, true interest and the relatedness of the research, mutual commitment and learning, communication intensity and interaction, and awareness of cultural and knowledge-related differences between collaboration partners. Theoretical and practical implications of the findings are suggested and discussed.

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Tutkielman tavoitteena oli selvittää, kuinka CRM-järjestelmä otetaan käyttöön asiakkuuksienhallinnan tueksi yritysten välisillä markkinoilla. Tutkielma keskittyy erityisesti käyttöönoton varhaisiin vaiheisiin selvittämällä, mikä on järjestelmien rooli asiakkuudenhallinnassa ja miten ne tukevat erilaisia käyttäjätasoja, jotka työssä jaettiin strategiseksi, operatiiviseksi ja analyyttiseksi tasoksi. Lisäksi työ esittelee käyttöönottoon yleisimmin liittyviä sudenkuoppia. Tutkielma on laadullinen tutkimus ja siinä on kuvattu CRM-järjestelmän käyttöönottoon liittyviä kysymyksiä yritysten välisillä markkinoilla toimivan caseyrityksen näkökulmasta. Tutkimuksessa havaittiin, että CRM-järjestelmän onnistunut käyttöönotto vaatii mahdollisimman yksinkertaista ja helppokäyttöistä järjestelmää. Käyttöönoton ei myöskään tulisi vaatia monimutkaista koulutusta, vaikkakin koulutusten tärkeys tunnistettiin. Tutkimus osoitti, että vaikka tämänhetkiset CRM-järjestelmät keskittyvät enemmän yksityiskohtaisten asiakasanalyysien tekoon, järjestelmä voi myös palvella asiakkaisiin liittyvän tiedon yhteisenä tallennus- ja jakamispaikkana. Lisäksi tutkimuksessa todettiin, että useimmiten potentiaaliset sudenkuopat olivat luonteeltaan hyvin käytännönläheisiä, kuten järjestelmän käyttämättömyys sekä huono motivointi ja sitouttaminen.

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Tutkimuksen tarkoituksena oli kuvata ja ymmärtää alaistaitoja Virolahden ja Miehikkälän kuntien palveluyhteistyössä Kaakon kaksikossa. Lisäksi kartoitettiin henkilöstön käsityksiä alaistaidoista ja merkityksestä työyhteisön johtamisen sekä henkilöstön vuorovaikutussuhteiden ja työhyvinvoinnin kehittämisessä. Tutkimus on laadullinen tapaustutkimus, jossa tutkimusmenetelmänä käytettiin teemahaastattelua yksilöhaastatteluna, joka tehtiin Kaakon kaksikon kuntien organisaatiossa kuudelletoista henkilölle. Tutkimustulosten mukaan alaistaitojen merkitys korostui kuntien siirtyessä palveluyhteistyöhön. Työntekijät ja esimiehet ymmärsivät alaistaidot käsitteenä melko samansuuntaisesti. Alaistaitojen kehittäminen lähtee henkilön oivalluksesta. Kehittäminen koettiin haasteeksi ja mahdollisuudeksi kuntajohtamisessa ja työhyvinvoinnissa. Tutkimuksen tulokset voidaan hyödyntää kunta- ja muiden organisaatioiden käyttöön henkilöstön koulutus- ja kehittämistyössä.

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Persistent luminescence materials can store energy from solar radiation or artificial lighting and release it over a period of several hours without a continuous excitation source. These materials are widely used to improve human safety in emergency and traffic signalization. They can also be utilized in novel applications including solar cells, medical diagnostics, radiation detectors and structural damage sensors. The development of these materials is currently based on methods based on trial and error. The tailoring of new materials is also hindered by the lack of knowledge on the role of their intrinsic and extrinsic lattice defects in the appropriate mechanisms. The goal of this work was to clarify the persistent luminescence mechanisms by combining ab initio density functional theory (DFT) calculations with selected experimental methods. The DFT approach enables a full control of both the nature of the defects and their locations in the host lattice. The materials studied in the present work, the distrontium magnesium disilicate (Sr2MgSi2O7) and strontium aluminate (SrAl2O4) are among the most efficient persistent luminescence hosts when doped with divalent europium Eu2+ and co-doped with trivalent rare earth ions R3+ (R: Y, La-Nd, Sm, Gd-Lu). The polycrystalline materials were prepared with the solid state method and their structural and phase purity was confirmed by X-ray powder diffraction. Their local crystal structure was studied by high-resolution transmission electron microscopy. The crystal and electronic structure of the nondoped as well as Eu2+, R2+/3+ and other defect containing materials were studied using DFT calculations. The experimental trap depths were obtained using thermoluminescence (TL) spectroscopy. The emission and excitation of Sr2MgSi2O7:Eu2+,Dy3+ were also studied. Significant modifications in the local crystal structure due to the Eu2+ ion and lattice defects were found by the experimental and DFT methods. The charge compensation effects induced by the R3+ co-doping further increased the number of defects and distortions in the host lattice. As for the electronic structure of Sr2MgSi2O7 and SrAl2O4, the experimental band gap energy of the host materials was well reproduced by the calculations. The DFT calculated Eu2+ and R2+/3+ 4fn as well as 4fn-15d1 ground states in the Sr2MgSi2O7 band structure provide an independent verification for an empirical model which is constructed using rather sparse experimental data for the R3+ and especially the R2+ ions. The intrinsic and defect induced electron traps were found to act together as energy storage sites contributing to the materials’ efficient persistent luminescence. The calculated trap energy range agreed with the trap structure of Sr2MgSi2O7 obtained using TL measurements. More experimental studies should be carried out for SrAl2O4 to compare with the DFT calculations. The calculated and experimental results show that the electron traps created by both the rare earth ions and vacancies are modified due to the defect aggregation and charge compensation effects. The relationships between this modification and the energy storage properties of the solid state materials are discussed.

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Företag inom industri och handel väljer allt oftare att låta ett logistikföretag sköta stora delar av sina logistiska processer. Logistikföretagen i sin tur överlåter utförandet av enskilda tjänster, som t.ex. olika typer av transport, till olika samarbetspartners inom branschen. I avhandlingen studeras hur logistikföretag går till väga då de väljer vilka av deras samarbetspartners som ska engageras för att delta i utförandet av ett logistiktjänstepaket, en arbetsprocess som här kallas aktivering. Fokus ligger på aktiveringens innehåll och de faktorer som inverkar på hur den går till och vilka samarbetsparter som kommer att engageras. Arbetet bygger på nätverksansatsen för studier av företagsrelationer på industriella marknader. Aktiveringsprocessen uppfattas som en rätt ordinär, rutinmässig verksamhet i företaget, men den kan också förväntas inverka på hur företagets samarbetsnätverk utvecklas över tiden, genom att vissa relationer förstärks medan andra försvagas. I den empi riska undersökningen deltog 29 logistikföretag i Åboregionen som utgående från ett diskussionsunderlag fick berätta om hur de går till väga vid aktivering.