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  • Dahlvik, Åsa (2005)
    Syftet med den här avhandlingen är att ta reda på hur kvinnor representeras i fyra tidningar. Jag har studerat Helsingin Sanomat, Hufvudstadsbladet, Ilta-Sanomat samt Iltalehti för att se hurdana representationer tidningarna förmedlar. Jag har undersökt dels hur bilderna skiljer mellan de olika tidningarna och dels vilka variationer det finns mellan bilder på kvinnor och bilder på män. Jag har tittat på vilken typ av bilder som förekommer, var bilderna placeras i tidningarna och hur bilderna fördelas mellan könen. Jag har tittat på personen storlek på bilden, hur ofta kvinnor förekommer på sport- och nyhetssidor, hur ofta kvinnor beskrivs och förekommer huvudsakligen i relation till män, som flickvänner och fruar till exempel, samt hur våra dagstidningar skiljer sig från våra eftermiddagstidningar. Min frågeställning i avhandlingen är: Vilken kvinnobild förmedlar våra ledande dagstidningar och eftermiddagstidningar? Vilka värderingar speglas och underbyggs av mediernas kvinnobild. Jag har använt kvantitativ innehållsanalys som metod. Eftersom variablerna man mäter innehållet med är likvärdiga får man jämförbara uppgifter. Den kvantitativa innehållsanalysen kännetecknas av att den möjliggör en objektiv, mätbar och verifierbar beskrivning av innehållet. Jag har vidare i min analys utgått från framingteorin och agenda-setting teorin. Resultatet av kodningen visade att bilderna på män dominerar samtliga tidningar, 45 % av alla bilder var bilder på män, motsvarande siffra för bilder på kvinnor var 19 %. Tidningarna hade alla fyra en liknande fördelning mellan män, kvinnor och barn, hälften män, en femtedel kvinnor och endast en bråkdel barn. Däremot fördelade sig bilderna på kvinnor olika i de olika tidningarna. I Iltalehti och Ilta Sanomat fanns det få bilder i kategorierna för politik och yrke medan kategorierna underhållning och missar och modeller var stora. I Helsingin Sanomat och Hufvudstadsbladet förekom knappast alls bilder på underhållare eller modeller, utan flest bilder placerades i kategorin för yrke eller kultur. Bilderna på män föreställer huvudsakligen politiker, yrkesutövare eller idrottsmän. Utgående från några av bilderna har jag tittat närmare på tidningarnas representationer, hur en könsroll skapas med hjälp av vissa element och vad som gör en bild till en typisk nyhetsbild eller sportbild. I avhandlingen ingår även diskussion kring bildanalys, stereotyper, könsroller samt tabloidisering.
  • Deng, Xianbao (Helsingin yliopisto, 2013)
    RNA silencing is a conserved mechanism that occurs in a broad range of eukaryotes, which is regulated by small RNAs (sRNAs). RNA silencing operates to control gene expression and maintain genome integrity. Virus-induced gene silencing (VIGS) in plants is a natural antivirus mechanism that has adapted from the general RNA silencing system. To counter the antivirus RNA silencing, plant viruses have evolved to encode viral suppressors of RNA silencing (VSRs). Nowadays VIGS is usually referred to as the technology that uses recombinant viruses to knock down the expression of plant endogenous genes. Gerbera hybrida (gerbera) is a model species in the family of Asteraceae. As a highly heterozygous species, gerbera lacks efficient functional genetic approaches other than gene transfer. The aim of the present study was to develop a Tobacco rattle virus (TRV, genus Tobravirus) induced gene silencing system for gerbera, and use TRV VIGS to characterize functions of chalcone synthase (CHS) encoding genes in the plant. Preliminary VIGS experiments on the cultivar Terraregina, by syringe infiltration and applying previously developed TRV vectors, did not result in visible VIGS phenotypes due to the absent of TRV RNA2 in the up non-infiltrated leaves. Consequently, I first aimed to study the mechanism of TRV VIGS, and tried to develop new VIGS vectors based on TRV RNA1. I investigated the role of two important TRV proteins of the 16K VSR and the 29K movement protein (MP) on TRV infection and TRV VIGS, and developed TRV RNA1 based VIGS vectors. For accomplishing this, a series of TRV RNA1 mutants have been constructed to disrupt the 16K, or to replace its 29K with Tobacco mosaic virus (TMV, genus Tobamovirus) 30K MP. TRV RNA1 vector, carrying a fragment of the gene encoding Nicotiana benthamiana PDS to replace part of the 16K sequence, induced PDS gene silencing systemically in N. benthamiana. However, this has found to be less efficiently than the original TRV VIGS system when the wild-type RNA1 and RNA2:PDS were used. The infection experiments demonstrated that 16K was required for TRV long distance movement, and helped in maintaining the integrity of the TRV RNA2 genome. In addition, TRV 29K alone did not suppress RNA silencing in the co-infiltration assay, but it could suppress RNA silencing in the context of RNA1 replication. TRV 29K may be the first VSR whose silencing suppression functions are found to be directly linked to viral replication. The original TRV vector system was finally adopted for VIGS in gerbera. TRV VIGS was optimized for gerbera by screening for TRV sensitive cultivars and by improving its inoculation methods. Intensive gene silencing phenotypes were achieved both in green tissues and in floral tissues, demonstrated by knocking down genes involved in isoprenoid biosynthesis (phytoene desaturase: GPDS; H and I subunits of Mg-chelatase: GChl-H and GChl-I), flower pigmentation (chalcone synthase: GCHS1), and flower development (GLOBOSA-like MADS domain transcription factor: GGLO1). Unexpectedly, a gerbera polyketide synthase encoding gene, G2PS1, that has no apparent connections to the carotenoid or chlorophyll biosynthesis, was knocked down by the photo-bleaching that was induced by the silencing of GPDS, GChl-H and GChl-I, or by the herbicide norflurazon. We have demonstrated for the first time that the using of VIGS in an Asteraceaeous species. Our data also suggested that the selection and use of a marker gene for VIGS should be strictly evaluated. A new CHS encoding gene, GCHS4, was characterized in gerbera. Together with the two previously identified GCHS1 and GCHS3, gerbera CHSs are represented by a three-gene family. Each gerbera CHS shows a distinct expression pattern. GCHS3 is particularly expressed in gerbera pappus. In partnership with the concomitantly expressed GCHS1, they are involved in the biosynthesis of colorless flavonoids. GCHS4 is the only CHS that is naturally expressed in the leaf petiole and inflorescence scape, and it is responsible for cyanidin biosynthesis in those tissues. GCHS4 is also the only CHS that was induced by environmental stresses in the leaf blade. Both GCHS1 and GCHS4 are markedly expressed in gerbera petals, and GCHS4 mRNA actually takes the majority of CHS mRNAs in the later stages of petal development. Nonetheless, VIGS experiments, by target silencing GCHS1 or GCHS4 independently, demonstrated that GCHS1 is the predominant functional CHS in gerbera petals. Thus, GCHS4 in gerbera petals seems to be regulated post-transcriptionally. In conclusion, the results of this study shed new light on the mechanism of TRV VIGS. The established TRV VIGS system provides a valuable tool for functional genomics in gerbera.
  • Sulavuori, Maarit (2006)
    The Signs of Safety method is a working method for assessing child welfare, devised by Australian social workers. A two-year project aiming to develop the procedure into a method applicable to Finnish child welfare, as well as to learn to use the method, was carried out by on Finnish Social Centre in southern Finland. The project also included an evaluation study, which analysed the development process by assessing how the development work succeeds at the actual workplace where the workload is heavy and working pace is hectic. Answers to the following questions were searched for: how do different employees accept the method, how was the method established into use, and what significance did the adopting process of the method have as regards the employees' maintenance of their working capacity. The study is process evaluation and, as a research paradigm, it entails both a constructivist and realistic evaluation method. The development project as a whole was evaluated with the help of project-assessment criteria deployed by the Finnish Centre for Health Promotion. All in all, the Signs of Safety project was a success: the Australian original was formed into a method applicable to Finnish circumstances. Nevertheless, when planning the process, one common problem in social work was ignored, that is, the large turnover of social workers and the resulting challenges to the development project. This had an impact on the final establishment of the method in everyday use. The social workers had different capabilities to try to test and apply the method. The employees who opposed the adoption of the method wanted change, but in order to internalise the method, they required an outside party to "give them a kick." Meanwhile, the adaptors were imprisoned in the daily monotony, subjected to constant hurry, and acted according to the old routine, largely discarding the new method. The social workers who had internalised the "only practice makes perfect" attitude were the ones who not only deployed the method but also revised it. Competent performers and experts used the method in a more courageous and applied way than fairly new workers or beginners who analysed the method but failed to mount the problems they encountered. In itself the project did not increase maintenance of working capacity, but as development work it constituted part of operations aiming at increased well-being and working capacity at work. It provided one possibility to reflect on work as well as to jointly consider what kind of activities could have longer-ranging impacts than the project did.
  • Äärilä, Johannes (2013)
    This thesis investigates the methods and principles used to calculate timberland return indices. By studying these existing indices and new possible methods, the study contributes to the accuracy and methodology of timberland return measurement. Attention towards timberland investing has been increasing among institutional investors, while at the same time timberland return indices are also being utilized by policy makers as supporting indicators for policy decisions. The possibility to measure timberlands returns exactly is understandably of great interest and a desirable goal. Previous literature does discuss the general aspects of timberland return measurement and index calculation, but very little about the actual index number theory and its implications to the timberland return measurement. For this reason, there exist some issues regarding the currently available indices that make them prone to bias and otherwise unfavorable and inappropriate in the context of index number theory. The four existing indices considered in this thesis are the NCREIF Timberland Index, John Hancock Timber Index, Timberland Performance Index and the index formula utilized by the Finnish Forest Research Institute. The results of the examination confirm the benefits of fully-regulated forest in index construction, as it offers a stable and comparable base for an index. Also the effects and trade-offs of price selection, interest rate and index frequency are presented and discussed in detail. The utilization of net present value in index construction, instead of the liquidation value, is a new approach utilized in this thesis and the issues regarding its use in index calculation are considered and assessed. The key finding of this thesis is that the index formula used by the Finnish Forest Research Institute suffers from a weighting problem and it is not consistent in aggregation. To overcome the index number problems present in the existing indices, the pseudo-superlative Montgomery-Vartia index formula is applied into timberland returns. It is shown that the index is consistent in aggregation and that it approximates closely the desirable superlative indices. As a result, this thesis advocates the use of Montgomery-Vartia index. It is more appropriate formula for timberland return measurement than the currently used or the other available index formulas are, and its implementation should therefore be considered.
  • Niemelä, Tarja (Helsingin yliopisto, 2013)
    Spring turnip rape (Brassica rapa ssp. oleifera) is the major oilseed crop cultivated in Finland. The earliness of turnip rape favours its cultivation in northern climates, but its seed yield is low. Hybrid breeding has been utilized in many agricultural crops to improve the seed yield. The exploitation depends on the degree of heterosis that a specific crop shows and on the requirement of a functional hybrid system to cross the parent lines in the production of F1 hybrid seed. In this thesis, the possibility to advance hybrid breeding in developing higher-yielding spring turnip rape cultivars was studied. Spring turnip rape expressed heterosis for increased seed yield. Composite hybrids showed significantly higher yield potential than open-pollinated cultivars. Testing the combining abilities of the parent lines is important in turnip rape. A high degree of variation in commercial heterosis for seed yield was observed between the tested combinations within the groups in both synthetics and composite hybrids. The highest yield increase achieved in this study was 18% in synthetics and 23% in composite hybrids. The Ogu-INRA CMS/Rf hybrid system was selected for the study. To generate a functional, fertility-restoring male line for turnip rape, the Kosena fertility-restoring Rfk1 gene, originating from Japanese radish (Raphanus sativus) and homologue to the Ogura fertility restoring gene Rfo, was transferred successfully from oilseed rape (B. napus) to turnip rape. Transferring of the gene was realized using interspecific crosses followed by traditional backcrossing. The TaqMan qPCR method proved useful in selecting homozygous restorer plants before flowering. Interpollination of selected plants instead of inbreeding is a benefit in cross-pollinating crops that suffer from inbreeding depression. The Rfk1 gene was able to restore the fertility of turnip rape with Ogura CMS, but the trait was unstable in the turnip rape genome. The Rfk1 gene was localized on an additional radish chromosome in the A genome of turnip rape. The BAC64 clone, carrying the Rfo locus, homolog to the Rfk1, identified the locus both in the additional radish chromosome and in the turnip rape chromosome (A09). The high homology of this locus between radish and turnip rape and its location in subterminal part of the chromosome in both genomes would facilitate the transfer of the fertility-restoring trait from radish to turnip rape. It was concluded that additional breeding techniques such as changing the ploidy level or using irradiation to increase the recombination activity between nonhomologous R and A genomes may be required. Even though 100% F1 hybrids were not tested here, the results of this thesis support the use of hybrid breeding in turnip rape. The breeding work towards a stable, fertility-restoring male line for the Ogu-INRA CMS/Rf hybrid system should be continued. To have a functional Ogu-INRA CMS/Rf hybrid system for turnip rape, it seems ideal if the homologous chromosomal area in the A genome could be substituted with the radish chromosome area having the restorer gene.
  • Hyytiäinen, Heli (Helsingin yliopisto, 2015)
    Stifle dysfunction is one of the most common reasons for canine hindlimb lameness and an indication for dogs referral to physiotherapy. Until now, there has been a lack of testing batteries in animal physiotherapy, although these are an important part of the evaluation process in various patient groups in human physiotherapy. Using 64 dogs, 43 with stifle dysfunction and 21 healthy dogs, congruity between fourteen physiotherapeutic evaluation methods, commonly used in dogs with stifle dysfunction, and six evaluation methods used by a veterinarian was evaluated. The eight best methods were chosen as items constituting a testing battery, the Finnish Canine Stifle Index (FCSI). The numerical scale of the testing battery was 0-263. Cronbach s alpha for the internal reliability of the total FCSI score was good (0.727). Two cut-offs for the total score were set: 60 and 120, separating adequate, compromised and severely compromised performance level, based on their high sensitivities and specificities. Another 57 dogs, 29 with some type of stifle dysfunction, 17 with some musculoskeletal disease other than stifle dysfunction and 11 healthy dogs, were used to further study the psychometric properties of the testing battery. The dogs with stifle dysfunction showed a significant (P < 0.001) decrease in FCSI total score (93.3 ± 62) compared with the two other groups (29.5 ± 39.6 and 11.7 ± 21.0), demonstrating good responsiveness of the FCSI. Also the inter-tester reliability was excellent (ICC 0.784), with no significant differences between three physiotherapists performing the FCSI. In conclusion, the overall functionality and outcome of rehabilitation in dogs with stifle dysfunction can be reliably evaluated with the new testing battery, the FCSI, developed here.
  • Amemori, Masamitsu (Helsingin yliopisto, 2012)
    Tobacco use adversely affects oral health. Tobacco use cessation (TUC) counselling guidelines recommend that brief TUC counselling should be provided to all tobacco users. In addition to TUC counselling, providing positive support to remain tobacco abstinent is particularly important among adolescents who are about to experiment with tobacco use. Despite excellent opportunities, implementation of tobacco use prevention and cessation (TUPAC) counselling among oral health professionals has proved challenging. Thus, the present study aimed to develop the assessment and promotion of TUPAC counselling among oral health professionals. A sample of Finnish dentists (n = 73) and dental hygienists (n = 22) employed by community dental clinics of the municipal health care regions of Tampere (28 clinics) and Vaasa (9 clinics) were invited to participate. Of those invited, 73 (76.8%) oral health professionals from 34 (91.9%) dental clinics participated. Applying a Theoretical Domains Framework (TDF), a 35-item Theoretical Domains Questionnaire (TDQ) was developed to assess factors influencing TUPAC counselling. The provision of TUC counselling at baseline was measured using a questionnaire and an electronic dental record audit to measure the effects of (1) educational and (2) educational + fee-for-service interventions. The estimates of internal consistency and factor analysis supported the reliability and validity of the TDQ developed. The present study showed that the provision of TUC counselling among a sample of oral health professionals was low. Identified implementation barriers suggest that the low adherence to TUPAC counselling could be due to reported environmental constraints (e.g. lack of support and resources), lack of skills, and low self-efficacy. Professional role and identity as well as memory, attention and decision processes were identified as potential determinants for TUPAC counselling. In assessing the effects of educational and education + fee-for-service interventions on preventive counselling, no statistically significant intervention effects were found. Regarding the provision of TUC counselling, signficiant group-by-time interaction showed that education alone and education with fee increased the implementation. . However, there was no statistically significant additional effect was received by adding fee-for-service to the education. In all groups, dental hygienists improved their preventive and cessation counselling more than dentists did. In conclusion, the data indicated a lack of competencies, environmental support and resources regarding TUPAC counselling. Educational intervention showed a favourable impact on the implementation of TUC counselling. In addition to education, interventions that promote professional role and identity in TUPAC counselling as well as interventions offering tools to support decision making (e.g. reminders, feedback) could prove effective.
  • Leppänen, Maija (2014)
    This thesis studies the current level of environmental management in the Ship Power business division within Wärtsilä corporation and aims to identify the related development needs. Hitherto environmental management has been mainly coordinated at the corporate level and implemented in local companies distributed geographically. Due to the recent organizational changes, however, the significance of division level environmental management in Ship Power has increased. The research goal is approached by examining the central elements of corporate environmental management and the challenges that the organizational structure places for it. Based on the findings, suggestions for further actions are given in order to develop the environmental management in Ship Power. Empirical data was collected through 35 qualitative interviews with Wärtsilä employees from different functions, business lines, and local companies in order to get a comprehensive view of environmental management in the Ship Power related activities. The interviews were semi-structured in order to provide answers for certain areas of concern, but also to enable the disclosure of topics not defined by the interviewer. The data is categorized into themes according to the theoretical background, and its analysis is based on inductive reasoning. Based on the findings, the environmental management in Ship Power is divided into two dimensions. The product-related environmental questions are handled in the business lines and the operational issues in the local companies. This fragmentation of the environmental knowledge causes inconsistent environmental focus at different organizational levels, and creates challenges to information sharing across the organization. The lack of corporate instructions on the environmental management system implementation has led to diverse practices in the local companies, and the lack of standardized documentation makes the internal comparison between them difficult. Therefore the experience gained from the local management systems does not support organizational learning throughout the corporation. While the product-related environmental aspects are the core of the business strategy, more attention could be paid to operational environmental management in Ship Power. For instance, the sharing of environmental knowledge could be strengthened in order to enhance employee awareness of the corporate practices and to facilitate the discussion of the best practices between the local units. A standardized documentation system would facilitate internal benchmarking and provide a means for centralized environmental performance follow-up. Because the local management systems are not sufficient to cover the global business processes, it would also be important to identify the environmental aspects in the Ship Power division. Furthermore, visible communication of the common environmental targets would help to create consistent environmental focus in Ship Power.
  • Parviainen, Suvi (Helsingin yliopisto, 2015)
    It has been estimated that up to half of people living in industrial societies will get cancer. Almost all cancer deaths are caused by metastatic disease and only few metastatic solid tumors can be cured with available therapies. Therefore, novel therapeutic modalities are needed. Genetically engineered oncolytic viruses such as adenoviruses and vaccinia viruses are a promising therapeutic approach given their capacity to specifically replicate in and kill tumor cells as well as to reach distant metastasis. Oncolytic viruses have demonstrated good safety, tolerability and promising signs of anti-tumor efficacy in several clinical trials, but the efficacy of the therapy needs improvement to reach its full clinical potential. Adenoviruses are one of the most studied vectors in oncolytic virotherapy. Two major obstacles limiting the efficacy have been insufficient transduction of the tumor cells and the recognition of the virus by the immune system, which rapidly clears the virus from systemic circulation, hampering the overall efficacy. This study shows that novel capsid modifications can increase the transduction efficacy and oncolytic potency of the virus, and that embedding oncolytic virus in a silica implant might help to circumvent the problem of clearance by prompting only modest immune responses against the virus. Recently, arming oncolytic viruses with immunomodulatory molecules has been a major focus in virotherapy. Immunotherapy means inducing the patient´s immune system to recognize and attack the tumor and has been recently linked with oncolytic virotherapy, as the replication of the virus in the tumor can be immunogenic per se and also release cancer epitopes available for antigen-presenting cells. Host immune responses have been shown to be a key player in oncolytic virotherapy as the balance between anti-viral and anti-tumoral immunity determines the efficacy of the therapy. Oncolytic vaccinia virus possesses unique immunogenicity and mechanisms of action that are distinct from other treatment modalities, and its self-perpetuating nature provides an ideal platform for therapeutic transgenic insertion. Therefore we engineered novel oncolytic vaccinia viruses with granulocyte-macrophage colony-stimulating factor (GMCSF) or CD40-ligand and studied their ability to increase the therapeutical outcome and anti-tumor immune responses in preclinical animal models. In the final part of the thesis the life cycle of oncolytic vaccinia virus was studied in more detail as we were able to show that the life cycle was compromised in a feline squamous cell carcinoma cell line. This finding might be important for a deeper understanding of the vaccinia virus-host cell interactions.
  • Vesikansa, Aino (Helsingin yliopisto, 2013)
    The development of glutamatergic transmission in the brain occurs gradually during the first postnatal weeks. During this critical period, nascent synaptic connections are finely tuned to form networks reliably transmitting and processing information. In the hippocampus, kainate receptors (KARs) are heavily expressed during early development and suggested to have an instrumental role in the activity-dependent development of neuronal connectivity. KARs are composed of various combinations of five subunits, GluK1-GluK5. Additional structural and functional diversity of receptors is achieved by alternative splicing and RNA editing of the subunits. The function of KARs differs from the other types of ionotropic glutamate receptors (iGluRs) in two essential respects: first, their primary role is not to mediate but to modulate transmission, and second, KARs use a non-canonical metabotropic signaling mechanism in addition to the classical ionotropic action. The diverse functional roles of KARs are reflected in their highly polarized subcellular localization, which is regulated in a subunit- and cell-specific manner. Despite the increasing number of roles characterized for KARs, their function during development is poorly understood. The aim of this study was to clarify the physiological roles of KARs in the developing glutamatergic connectivity in area CA1 of the rat hippocampus. First, we present a novel, developmentally restricted type of endogenous KAR activity, which has major influence on glutamatergic transmission in the immature hippocampus. During early development, high affinity G-protein-coupled presynaptic KARs are shown to be tonically activated by ambient glutamate to maintain a low probability of glutamate release in a subpopulation of CA3-CA1 synapses. This KAR-mediated presynaptic silencing has a critical impact on the transmission of glutamatergic information; KARs filter out sporadic low-frequency activity and promote transmission during highfrequency bursts representing natural-type of activiy within the immature hippocampal network. Next, we demonstrate that the GluK1c splice variant plays a pivotal role in immature-type KAR activity. The developmental and cell-type specific expression pattern of GluK1c mRNA corresponds to the tonic KAR activity. Furthermore, the presynaptic expression of GluK1c is shown to directly suppress glutamatergic transmission in cell-pairs in vitro and to mimic tonic KAR activity at CA3-CA1 synapses in vivo at a developmental stage when the immature-type KAR activity is already downregulated. Thus, the developmental downregulation of tonic KAR activation can be fully explained by the loss the GluK1c expression in CA3 pyramidal cells. We further show that activity-dependent mechanisms, such as the experimental induction of LTP, can rapidly downregulate tonic KAR activity and switch immature, labile synapses to mature ones. This involves a modification of the receptor per se, leading to the loss of high-affinity KARs. Finally, we show the critical involvement of tonic KAR activity in the formation /stabilization of glutamatergic connections in the hippocampal slice cultures. Mimicking tonic KAR activity by pharmacological activation of GluK1 containing KARs resulted in significant and permanent increase in the number of functional glutamatergic synapses. The essential role of endogenous KAR activity was indicated by the finding that blocking KARs during the period of intense synaptogenesis led to dramatic decrease in glutamatergic connectivity later in development. In summary, the novel findings of this work demonstrate that endogenous KAR activity has crucial role in modulating the glutamatergic transmission and connectivity in the developing hippocampus. This not only broadens our view of the activity-dependent mechanisms underlying the development of synaptic connectivity in the brain, but also provides a basis for understanding the pathophysiological functions of KARs in neurodevelopmental disorders.
  • Heikkonen, Hanna-Lotta (2014)
    The goal of this research was to produce guidelines for an eco-labeling program of wood and paper products in the U.S. market. The factors affecting consumers’ willingness to pay for eco-labeled wood and paper products were examined using a metaregression analysis. A systematic literature review was conducted to examine what are the preferable on-product label characteristics. Results show that consumers in North America are willing to pay less for eco-labeled wood and paper products than European consumers. Wooden and durable goods are able to capture larger price premiums compared to less durable wood/paper products. Consumers are willing to pay more for eco-labeled products where the labels provide more information to the consumers. Among demographic variables, age is shown to positively influence the amount consumers are willing to pay for eco-labeled wood and paper products. Among desirable label characteristics contact information of the labeling agency and information about the environmental effects of the product were found important in addition to information enabling product comparison. Environmental non-governmental organizations are perceived as the most credible labeling providers as shown in past studies.
  • Eklund, Tommy (2013)
    Large screens, interactive or not, are becoming a common sight at shopping centers and other public places. These screens are used to advertise or share information interactively. Combined with the omnipresence of smartphones this gives rise for a unique opportunity to join these two interfaces and to combine their strengths and complement their weaknesses. Smartphones are very mobile thanks to their small size and can access information virtually from anywhere, but suffer from overflow of information. Users have too many applications and web sites to search relevant information to find what they want or need in a timely fashion. On the other hand, public screens are too large to provide information everywhere or in a personalized way, but they do often have the information you need, when and where you need it. Thus large screens provide an ideal place for users to select content onto their smartphones. Large screens also have the advantage of screen size and research has indicated that using a second screen with small handheld devices can improve the user experience. This thesis undertook design and development of a prototype Android application for existing large interactive public screen. The initial goal was to study the different aspects of personal mobile devices coupled with large public screens. This large screen interface is also under development as a ubiquitous system and the mobile application was designed to be part of this system. Thus the design of the mobile application needed to be consistent with the public screen. During the development of this application it was observed that the small mobile screen could not support the content or interactions designed for a much larger screen because of its small size. As a result this thesis focuses on developing a prototype that further research could draw upon. This lead to a study of small screen graph data visualization and previous research on mobile applications working together with large public screens. This thesis presents a novel approach for displaying graph data designed for large screens on a small mobile screen. This work also discusses many challenges and questions related to large screen interaction with mobile device that rose during the development of the prototype. An evaluation was conducted to gather both quantitative and qualitative data on the interface design and the consistency with the large screen interface to further analyze the resulting prototype. The most important findings in this work are the problems encountered and questions raised during the development of the mobile application prototype. This thesis provides several suggestions for future research using the application, the ubiquitous system and the large screen interface. The study of related work and prototype development also lead to suggestion of design guidelines for this type of applications. The evaluation data also suggests that the final mobile application design is both consistent with and performs better than a faithful implementation of the visuals and interaction model of the original large screen interface.
  • Ruottu, Toni (Helsingin yliopisto, 2011)
    As the virtual world grows more complex, finding a standard way for storing data becomes increasingly important. Ideally, each data item would be brought into the computer system only once. References for data items need to be cryptographically verifiable, so the data can maintain its identity while being passed around. This way there will be only one copy of the users family photo album, while the user can use multiple tools to show or manipulate the album. Copies of users data could be stored on some of his family members computer, some of his computers, but also at some online services which he uses. When all actors operate over one replicated copy of the data, the system automatically avoids a single point of failure. Thus the data will not disappear with one computer breaking, or one service provider going out of business. One shared copy also makes it possible to delete a piece of data from all systems at once, on users request. In our research we tried to find a model that would make data manageable to users, and make it possible to have the same data stored at various locations. We studied three systems, Persona, Freenet, and GNUnet, that suggest different models for protecting user data. The main application areas of the systems studied include securing online social networks, providing anonymous web, and preventing censorship in file-sharing. Each of the systems studied store user data on machines belonging to third parties. The systems differ in measures they take to protect their users from data loss, forged information, censorship, and being monitored. All of the systems use cryptography to secure names used for the content, and to protect the data from outsiders. Based on the gained knowledge, we built a prototype platform called Peerscape, which stores user data in a synchronized, protected database. Data items themselves are protected with cryptography against forgery, but not encrypted as the focus has been disseminating the data directly among family and friends instead of letting third parties store the information. We turned the synchronizing database into peer-to-peer web by revealing its contents through an integrated http server. The REST-like http API supports development of applications in javascript. To evaluate the platform s suitability for application development we wrote some simple applications, including a public chat room, bittorrent site, and a flower growing game. During our early tests we came to the conclusion that using the platform for simple applications works well. As web standards develop further, writing applications for the platform should become easier. Any system this complex will have its problems, and we are not expecting our platform to replace the existing web, but are fairly impressed with the results and consider our work important from the perspective of managing user data.
  • Tuominen, Pirkko (Helsingin yliopisto, 2009)
    The drive for risk-based food safety management, systems and control has spread world-wide in recent decades. Since the term is still internationally undefined, its use and implementation vary, producing different realizations. In this Ph.D. thesis, microbiological risk assessment (MRA) was investigated as a basis for risk-based food safety management, which was defined as ‘food safety management based on risk assessment in order to achieve an appropriate level of protection (ALOP)’. Governments are responsible for commissioning MRAs and also for setting food safety targets up to a certain point, but the practical management measures that need to be in place in order to achieve the targets are to be addressed by the operators. On the plant level, food safety is usually managed through regulation, quality assurance systems and a hazard analysis and critical control point (HACCP) programme with its prerequisites. In Finland, food safety management on the food plant level is implemented through an HACCP-like regulated system termed an own-checking (OC) programme. A quantitative microbiological risk assessment (QMRA) was conducted on salmonella in the beef production chain according to the official standards of the Codex Alimentarius Commission (Codex Alimentarius), and utilized in determining the food safety metrics for beef production. The Finnish Salmonella Control Programme (FSCP) and the main official interventions due to it were examined in the light of risk-based food safety management. The targets set for beef processing plants by the government were converted into quantitative limits, and the results of salmonella monitoring included in the FSCP were examined by the QMRA. The goal of the FSCP was declared in 1994 to ‘maintain the present salmonella situation’, which was considered to refer to the salmonella incidence in humans at that time, and also the de facto ALOP. The requirement for a maximum salmonella prevalence of 1% at defined stages of the beef production chain was embodied in the FSCP. This statement was considered to convey performance objectives (PO) for the aforementioned stages. According to the QMRA, the de facto ALOP was achieved in the referred year 1999, and even the true prevalence levels in the FSCP were estimated to be clearly under the set PO limits with 95% credibility. However, the PO limits were set too high for the de facto ALOP to be maintained in practice. If the salmonella prevalence reached the PO limit of 1% or values near it, the public health risk would increase and overrun the de facto ALOP. The QMRA produced in this work has for the first time provided the possibility to quantitatively asses the relationships between targets set in the FSCP and their impact on public health. At present, imports of beef and beef-derived foods may impose on Finnish consumers a significantly greater exposure than domestic products. If their salmonella prevalence or their share of the foods consumed in Finland increase, the number of human cases could rapidly rise. The models for the QMRA were mainly Bayesian hierarchical models using Markov chain Monte Carlo (MCMC) techniques, which was found to be a flexible and appropriate method for this type of complex modelling. The resulting distributions were also regarded as an advantage compared to the results from models developed with the deterministic approach, because the presentation of results included the extent of the uncertainty, and also in this manner better illustrated the actual operational environment. Based on an inquiry, the personnel in food processing plants had a positive attitude towards food safety management systems, but the knowledge, training and involvement of those employees directly operating on the site with these systems were discovered to be deficient. Therefore, a generic semi-quantitative hygiene risk assessment model, Hygram®, was developed for small and medium-sized food enterprises to offer assistance in understanding, training, and, first of all, detecting the critical steps of the processes, and thereby to contribute to the development of their own-checking systems towards risk-based food safety management. Hygram® was not considered a risk-based tool as such, but whenever the critical limits of the process have been defined as equal to a risk assessment, Hygram® can be used as a risk-based management tool. It can also serve as a tool for systematic hazard analysis and CCP detection when establishing a food safety management system. To conclude, the development of risk-based food safety management is a process in which risk assessment is an essential tool. Scientific, technical, psychological and resource-bound barriers need to be overcome in order to put risk-based management systems into practice. This study showed that QMRA can be valuable in national risk management decision making, although few QMRAs are currently available. Appropriate tools for practical risk management decision making on the industrial level, such as Hygram®, need to be further developed.
  • Hagos, Elias Nahusenay (Helsingin yliopisto, 2015)
    Ethiopia is Africa’s biggest coffee exporter nation with deep history. Coffee discovered in Ethiopia and it continues to be pivotal for the country in many fronts till to date. The coffee linkage with Ethiopia is deep-rooted many historians believe back in 9th century coffee discovered by Kaldi, a goat herder. He discovered it after noticing coffee’s energizing effect on his goats. The word coffee itself also derived from place called ‘Kaffa’ where the trees blossomed. Coffee gradually became a world obsession by spreading from highlands of Ethiopia traveled along spice routes to Yemen, Turkey and Europe. Coffee exporting is a significant portion of Ethiopian economy. It accommodates more than twenty five million peasants which indicate its magnitude for the country. It is one of the leading sources of income for the government and other stakeholders. The establishment of Ethiopian Commodity Exchange (ECX) has seen the Ethiopian coffee trade system being transformed. It created a platform of primary, secondary and tertiary market divisions. In a way that the coffee can be traded based on value addition from one division to the other. Unlike the previous centralized warehousing system, it introduced decentralized warehousing and liquoring centers across the country where the coffee quality checked by use of laboratory tasting. It gives a temporary produce storage services until the coffee is sold and ownership of the produce transferred from seller to buyer. The introduction of modernized and transparent system enabled economic gain and helped farmers to enhance their life conditions. The objective of this study was to identify some of the contradictions that are solved in Ethiopian coffee trade activity by the establishment of ECX. In addition, the emerging contradictions and prevailing disturbances at present as well as the overall benefits it brought in relation to farmers’ day to day life conditions were analyzed.
  • Vuontela, Virve (Helsingin yliopisto, 2008)
    Intact function of working memory (WM) is essential for children and adults to cope with every day life. Children with deficits in WM mechanisms have learning difficulties that are often accompanied by behavioral problems. The neural processes subserving WM, and brain structures underlying this system, continue to develop during childhood till adolescence and young adulthood. With functional magnetic resonance imaging (fMRI) it is possible to investigate the organization and development of WM. The present thesis aimed to investigate, using behavioral and neuroimaging methods, whether mnemonic processing of spatial and nonspatial visual information is segregated in the developing and mature human brain. A further aim in this research was to investigate the organization and development of audiospatial and visuospatial information processing in WM. The behavioral results showed that spatial and nonspatial visual WM processing is segregated in the adult brain. The fMRI result in children suggested that memory load related processing of spatial and nonspatial visual information engages common cortical networks, whereas selective attention to either type of stimuli recruits partially segregated areas in the frontal, parietal and occipital cortices. Deactivation mechanisms that are important in the performance of WM tasks in adults are already operational in healthy school-aged children. Electrophysiological evidence suggested segregated mnemonic processing of visual and auditory location information. The results of the development of audiospatial and visuospatial WM demonstrate that WM performance improves with age, suggesting functional maturation of underlying cognitive processes and brain areas. The development of the performance of spatial WM tasks follows a different time course in boys and girls indicating a larger degree of immaturity in the male than female WM systems. Furthermore, the differences in mastering auditory and visual WM tasks may indicate that visual WM reaches functional maturity earlier than the corresponding auditory system. Spatial WM deficits may underlie some learning difficulties and behavioral problems related to impulsivity, difficulties in concentration, and hyperactivity. Alternatively, anxiety or depressive symptoms may affect WM function and the ability to concentrate, being thus the primary cause of poor academic achievement in children.
  • Shulga, Anastasia (Helsingin yliopisto, 2011)
    Traumatic insults to the central nervous system are frequently followed by profound and irreversible neuronal loss as well as the inability of the damaged neurons to regenerate. One of the major therapeutic challenges is to increase the amount of surviving neurons after trauma. Thus it is crucial to understand how injury affects neuronal responses and which conditions are optimal for survival to prevent neuronal loss. During development neuronal survival is thought to be dependent on the competition for the availability of survival-promoting molecules called neurotrophic factors. Much less is known on the survival mechanisms of mature neurons under traumatic conditions. Increasing amount of evidence points towards the possibility that after injury neuronal responses might aquire some developmental characteristics. One of the important examples is the change in the responses to the neurotransmitter GABA: it is inhibitory in the intact mature neurons, but can induce excitation during development and after trauma. An important step in the maturation of GABAergic transmission in the CNS is the developmental shift in the action of GABAA receptor from depolarization in immature neurons to hyperpolarization in mature neurons. GABAA-mediated responses are tightly linked to the homeostasis of the chloride anion (Cl-), which in neurons is mainly regulated by Na+-K+-2Cl- cotransporter NKCC1 and K+-Cl- cotransporter KCC2. Trauma-induced functional downregulation of KCC2 promotes a shift from hyperpolarizing GABAA-mediated responses to depolarizing. Other important consequences of neuronal trauma are the emergence of dependency of central neurons on brain-derived neuro¬trophic factor (BDNF) for survival, as well as the upregulation of neurotrophin receptor p75NTR. Our aim was to answer the question whether these post-traumatic events are interrelated, and whether the regulation of BDNF and KCC2 expression is different under traumatic conditions and in intact neurons. To study responses of injured mature central neurons, we used an in vitro and in vivo axotomy models. For in vitro studies, we lesioned organotypic hippocampal slices between CA3 and CA1 regions, which resulted in selective axotomy of the CA3 neurons and denervation of the CA1 neurons. Some experiments were repeated in vivo by lesioning the neurons of the corticospinal tract at the internal capsule level, or by lesioning spinal motoneurons at the ventral root. We show that intact mature neurons do not require BDNF for survival, whereas in axotomized neurons apoptosis is induced upon BDNF deprivation. We further show that post-traumatic dependency on BDNF is mediated by injury-induced upregulation of p75NTR. Post-traumatic increase in p75NTR is induced by GABAA-mediated depolarization, consequent opening of voltage-gated Ca2+ channels, and the activation of Rho kinase ROCK. Thus, post-traumatic KCC2 downregulation leads to the dependency on BDNF through the induction of p75NTR upregulation. Neurons that survive after axotomy over longer period of time lose BDNF dependency and regain normal KCC2 levels. This phenomenon is promoted by BDNF itself, since after axotomy contrary to normal conditions KCC2 is upregulated by BDNF. The developmentally important thyroid hormone thyroxin regulates BDNF expression during development. We show that in mature intact neurons thyroxin downregulates BDNF, whereas after axotomy thyroxin upregulates BDNF. The elevation of BDNF expression by thyroxin promoted survival of injured neurons. In addition, thyroxin also enhanced axonal regeneration and promoted the regaining of normal levels of KCC2. Thus we show that this hormone acts at several levels on the axotomy-initiated chain of events described in the present work, and could be a potential therapeutic agent for the injured neurons. We have also characterized a previously unknown downregulatory interaction between thyroxin and KCC2 in intact neurons. In conclusion, we identified several important interactions at the neurotrophin-protein and hormone-neurotrophin level that acquire immature-like characteristics after axotomy and elucidated an important part of the mechanism by which axotomy leads to the requirement of BDNF trophic support. Based on these findings, we propose a new potential therapeutic strategy where developmentally crucial agents could be used to enhance survival and regeneration of axotomized mature central neurons.
  • Luchkina, Natalia V. (Helsingin yliopisto, 2015)
    Activity-dependent synaptic plasticity, and long-term potentiation in particular, represents the predominant model of memory and learning at the cellular level. In addition, synaptic plasticity plays a critical role in the activity-dependent refinement and fine-tuning of neuronal circuits during development by maintaining and stabilising certain synaptic connections and eliminating others. The main goal of this project was to increase our understanding of the molecular mechanisms underlying activity-dependent synaptic plasticity in the developing brain, with particular emphasis on the mechanisms that are specific to early postnatal development. First, we characterise in detail the properties of developmentally restricted neonatal presynaptic long-term potentiation (LTP) in CA1 area of the hippocampus and demonstrate its susceptibility to regulation via protein kinase C (PKC) signalling. Next, we explore the physiological functions of GluA4 subunit-containing AMPA type glutamate receptors, predominantly expressed at developing CA3 CA1 synapses. We show that GluA4 expression is necessary for protein kinase A (PKA)-dependent LTP at immature synapses. Further, the loss of GluA4 expression in parallel with circuit maturation explains the developmental switch in LTP signalling requirements from PKA- to Ca2+/calmodulin-dependent protein kinase II (CaMKII)-dependent. Further, we also explore the role of GluA4 C-terminal interaction partners in synaptic trafficking of GluA4-containing AMPA receptors and its importance for synapse maturation. We confirm a critical role for the membrane proximal region of GluA4 C-terminal domain in trafficking and identify a novel mechanism for activity-dependent synaptic delivery of GluA4 by the extreme C-terminal region. Finally, we show an important role of the GluA4 subunit in strengthening of AMPA receptor-mediated transmission, observed during early postnatal development. In summary, we provide novel information on the pre- and postsynaptic plasticity mechanisms operating at hippocampal CA3 CA1 synapses during the critical period of activity-dependent maturation of glutamatergic neuronal circuitry in rodents. This expands our knowledge on the cellular mechanisms guiding development of synaptic connectivity in the brain. Dysfunction of such mechanisms may play fundamental roles in the underlying pathophysiological causes of various neurodevelopmental disorders.