30 resultados para Animal industry

em Helda - Digital Repository of University of Helsinki


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Neuronal ceroid lipofuscinoses (NCLs) are a family of inherited pediatric neurodegenerative disorders, leading to retinal degeneration, death of selective neuronal populations and accumulation of autofluorscent ceroid-lipopigments. The clinical manifestations are generally similar in all forms. The Finnish variant late infantile neuronal ceroid lipofuscinosis (vLINCLFin) is a form of NCL, especially enriched in the Finnish population. The aim of this thesis was to analyse the brain pathology of vLINCLFin utilising the novel Cln5-/- mouse model. Gene expression profiling of the brains of already symptomatic Cln5-/- mice revealed that inflammation, neurodegeneration and defects in myelinization are the major characteristics of the later stages of the disease. Histological characterization of the brain pathology confirmed that the thalamocortical system is affected in Cln5-/- mice, similarly to the other NCL mouse models. However, whereas the brain pathology in all other analyzed NCL mice initiate in the thalamus and spread only months later to the cortex, we observed that the sequence of events is uniquely reversed in Cln5-/- mice; beginning in the cortex and spreading to the thalamus only months later. We could also show that even though neurodegeneration is inititated in the cortex, reactive gliosis and loss of myelin are evident in specific nuclei of the thalamus already in the 1 month old brain. To obtain a deeper insight into the disturbed metabolic pathways, we performed gene expression profiling of presymptomatic mouse brains. We validated these findings with immunohistological analyses, and could show that cytoskeleton and myelin were affected in Cln5-/- mice. Comparison of gene expression profiling results of Cln5-/- and Cln1-/- mice, further highlighted that these two NCL models share a common defective pathway, leading to disturbances in the neuronal growth cone and cytoskeleton. Encouraged by the evidence of this defected pathway, we analyzed the molecular interactions of NCL-proteins and observed that Cln5 and Cln1/Ppt1 proteins interact with each other. Furthermore, we demonstrated that Cln5 and Cln1/Ppt1 share an interaction partner, the F1-ATP synthase, potentially linking both vLINCLFIN and INCL diseases to disturbed lipid metabolism. In addition, Cln5 was shown to interact with other NCL proteins; Cln2, Cln3, Cln6 and Cln8, implicating a central role for Cln5 in the NCL pathophysiology. This study is the first to describe the brain pathology and gene expression changes in the Cln5-/- mouse. Together the findings presented in this thesis represent novel information of the disease processes and the molecular mechanisms behind vLINCLFin and have highlighted that vLINCLFin forms a very important model to analyze the pathophysiology of NCL diseases.

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The purpose of this study was to extend understanding of how large firms pursuing sustained and profitable growth manage organisational renewal. A multiple-case study was conducted in 27 North American and European wood-industry companies, of which 11 were chosen for closer study. The study combined the organisational-capabilities approach to strategic management with corporate-entrepreneurship thinking. It charted the further development of an identification and classification system for capabilities comprising three dimensions: (i) the dynamism between firm-specific and industry-significant capabilities, (ii) hierarchies of capabilities and capability portfolios, and (iii) their internal structure. Capability building was analysed in the context of the organisational design, the technological systems and the type of resource-bundling process (creating new vs. entrenching existing capabilities). The thesis describes the current capability portfolios and the organisational changes in the case companies. It also clarifies the mechanisms through which companies can influence the balance between knowledge search and the efficiency of knowledge transfer and integration in their daily business activities, and consequently the diversity of their capability portfolio and the breadth and novelty of their product/service range. The largest wood-industry companies of today must develop a seemingly dual strategic focus: they have to combine leading-edge, innovative solutions with cost-efficient, large-scale production. The use of modern technology in production was no longer a primary source of competitiveness in the case companies, but rather belonged to the portfolio of basic capabilities. Knowledge and information management had become an industry imperative, on a par with cost effectiveness. Yet, during the period of this research, the case companies were better in supporting growth in volume of the existing activity than growth through new economic activities. Customer-driven, incremental innovation was preferred over firm-driven innovation through experimentation. The three main constraints on organisational renewal were the lack of slack resources, the aim for lean, centralised designs, and the inward-bound communication climate.

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The basis for this study was in poor attractiveness of the wood products industry among young people as a field to study and work in. The purpose was to produce new information of how to improve the relationship between young people and the wood products industry in order to better attract young people with different relational orientation. A survey was conducted among students of comprehensive schools and students of wood industry at vocational schools selected by systematic cluster sampling. The final sample consisted of 613 students. The study combined the theories and concepts of relationships, communication and trust of several disciplines. In addition, it applied theories of relationship marketing, stakeholders, publics, involvement and concepts of reputation and values. It studied the central relational elements in the form of antecedents, relationship state and its consequences. The study examined, how young people with different background and level of interest perceive wood industry as a field to study and work in from relational point of view, what are the central deficiencies in perceived relational elements and what are the public relations activities enhancing the relationship between wood industry and young people with less and high interest in the sector. The results indicate poor visibility of the wood industry among young people: unfamiliarity with the industry and unawareness of the opportunities to study in the field. It appeared that instead of increasing only information sharing, interactive communication in different forms is needed. The study also suggests that behaviors of the industry sector advancing perceived trustworthiness are of crucial importance. Moreover, the wood industry needs to pay attention to its behaviors and communication also among other stakeholder groups, especially the media, as reputation plays an important role in building up trust and satisfaction between young people and the sector. Finally, the less and highly interested young people were found to assess the relationship partly through different relational elements. In order to develop the relationship with highly interested young people they should be regarded clearly as future employees of the wood industry through activities affirming that they are desired and valued employees in the sector. Further, openness of information disclosure, whether concerning current situation or future prospects, seems to increase credibility and attractiveness of the wood industry. Highly interested young people were also found to appreciate socially responsible activities. The less interested young people seem to be insecure about the reliability of the wood industry as an employer, as well as, its ability and interest to invest in young people s skills. In addition,involvement in issues relevant for young people was found crucial in enhancing the relationship with the less interested young people.The conclusions of the study provide tools for enhancing the attractiveness of the wood industry among young people not only to the industry itself, but also to its advocates, teachers and student counselors of comprehensive and vocational schools, authorities and policy makers.

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B. cereus is a gram-positive bacterium that possesses two different forms of life:the large, rod-shaped cells (ca. 0.002 mm by 0.004 mm) that are able to propagate and the small (0.001 mm), oval shaped spores. The spores can survive in almost any environment for up to centuries without nourishment or water. They are insensitive towards most agents that normally kill bacteria: heating up to several hours at 90 ºC, radiation, disinfectants and extreme alkaline (≥ pH 13) and acid (≤ pH 1) environment. The spores are highly hydrophobic and therefore make them tend to stick to all kinds of surfaces, steel, plastics and live cells. In favorable conditions the spores of B. cereus may germinate into vegetative cells capable of producing food poisoning toxins. The toxins can be heat-labile protein formed after ingestion of the contaminated food, inside the gastrointestinal tract (diarrhoeal toxins), or heat stable peptides formed in the food (emesis causing toxin, cereulide). Cereulide cannot be inactivated in foods by cooking or any other procedure applicable on food. Cereulide in consumed food causes serious illness in human, even fatalities. In this thesis, B. cereus strains originating from different kinds of foods and environments and 8 different countries were inspected for their capability of forming cereulide. Of the 1041 isolates from soil, animal feed, water, air, used bedding, grass, dung and equipment only 1.2 % were capable of producing cereulide, whereas of the 144 isolates originating from foods 24 % were cereulide producers. Cereulide was detected by two methods: by its toxicity towards mammalian cells (sperm assay) and by its peculiar chemical structure using liquid-chromatograph-mass spectrometry equipment. B. cereus is known as one of the most frequent bacteria occurring in food. Most foods contain more than one kind of B. cereus. When randomly selected 100 isolates of B. cereus from commercial infant foods (dry formulas) were tested, 11% of these produced cereulide. Considering a frequent content of 103 to 104 cfu (colony forming units) of B. cereus per gram of infant food formula (dry), it appears likely that most servings (200 ml, 30 g of the powder reconstituted with water) may contain cereulide producers. When a reconstituted infant formula was inoculated with >105 cfu of cereulide producing B. cereus per ml and left at room temperature, cereulide accumulated to food poisoning levels (> 0.1 mg of cereulide per serving) within 24 hours. Paradoxically, the amount of cereulide (per g of food) increased 10 to 50 fold when the food was diluted 4 - 15 fold with water. The amount of the produced cereulide strongly depended on the composition of the formula: most toxin was formed in formulas with cereals mixed with milk, and least toxin in formulas based on milk only. In spite of the aggressive cleaning practices executed by the modern dairy industry, certain genotypes of B. cereus appear to colonise the silos tanks. In this thesis four strategies to explain their survival of their spores in dairy silos were identified. First, high survival (log 15 min kill ≤ 1.5) in the hot alkaline (pH >13) wash liquid, used at the dairies for cleaning-in-place. Second, efficient adherence of the spores to stainless steel from cold water. Third, a cereulide producing group with spores characterized by slow germination in rich medium and well preserved viability when exposed to heating at 90 ºC. Fourth, spores capable of germinating at 8 ºC and possessing the psychrotolerance gene, cspA. There were indications that spores highly resistant to hot 1% sodium hydroxide may be effectively inactivated by hot 0.9% nitric acid. Eight out of the 14 dairy silo tank isolates possessing hot alkali resistant spores were capable of germinating and forming biofilm in whole milk, not previously reported for B. cereus. In this thesis it was shown that cereulide producing B. cereus was capable of inhibiting the growth of cereulide non-producing B. cereus occurring in the same food. This phenomenon, called antagonism, has long been known to exist between B. cereus and other microbial species, e.g. various species of Bacillus, gram-negative bacteria and plant pathogenic fungi. In this thesis intra-species antagonism of B. cereus was shown for the first time. This brother-killing did not depend on the cereulide molecule, also some of the cereulide non-producers were potent antagonists. Interestingly, the antagonistic clades were most frequently found in isolates from food implicated with human illness. The antagonistic property was therefore proposed in this thesis as a novel virulence factor that increases the human morbidity of the species B. cereus, in particular of the cereulide producers.

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Recent epidemiological studies have shown a consistent association of the mass concentration of urban air thoracic (PM10) and fine (PM2.5) particles with mortality and morbidity among cardiorespiratory patients. However, the chemical characteristics of different particulate size ranges and the biological mechanisms responsible for these adverse health effects are not well known. The principal aims of this thesis were to validate a high volume cascade impactor (HVCI) for the collection of particulate matter for physicochemical and toxicological studies, and to make an in-depth chemical and source characterisation of samples collected during different pollution situations. The particulate samples were collected with the HVCI, virtual impactors and a Berner low pressure impactor in six European cities: Helsinki, Duisburg, Prague, Amsterdam, Barcelona and Athens. The samples were analysed for particle mass, common ions, total and water-soluble elements as well as elemental and organic carbon. Laboratory calibration and field comparisons indicated that the HVCI can provide a unique large capacity, high efficiency sampling of size-segregated aerosol particles. The cutoff sizes of the recommended HVCI configuration were 2.4, 0.9 and 0.2 μm. The HVCI mass concentrations were in a good agreement with the reference methods, but the chemical composition of especially the fine particulate samples showed some differences. This implies that the chemical characterization of the exposure variable in toxicological studies needs to be done from the same HVCI samples as used in cell and animal studies. The data from parallel, low volume reference samplers provide valuable additional information for chemical mass closure and source assessment. The major components of PM2.5 in the virtual impactor samples were carbonaceous compounds, secondary inorganic ions and sea salt, whereas those of coarse particles (PM2.5-10) were soil-derived compounds, carbonaceous compounds, sea salt and nitrate. The major and minor components together accounted for 77-106% and 77-96% of the gravimetrically-measured masses of fine and coarse particles, respectively. Relatively large differences between sampling campaigns were observed in the organic carbon content of the PM2.5 samples as well as the mineral composition of the PM2.5-10 samples. A source assessment based on chemical tracers suggested clear differences in the dominant sources (e.g. traffic, residential heating with solid fuels, metal industry plants, regional or long-range transport) between the sampling campaigns. In summary, the field campaigns exhibited different profiles with regard to particulate sources, size distribution and chemical composition, thus, providing a highly useful setup for toxicological studies on the size-segregated HVCI samples.

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Three strategically important uses of IT in the construction industry are the storage and management of project documents on webservers (EDM), the electronic handling of orders and invoices between companies (EDI) and the use of 3-D models including non-geometrical attributes for integrated design and construction (BIM). In a broad longitudinal survey study of IT use in the Swedish Construction Industry the extent of use of these techniques was measured in 1998, 2000 and 2007. The results showed that EDM and EDI are currently already well-established techniques whereas BIM, although it promises the biggest potential benefits to the industry, only seems to be at the beginning of adoption. In a follow-up to the quantitative studies, the factors affecting the decisions to implement EDM, EDI and BIM as well as the actual adoption processes, were studied using semi-structured interviews with practitioners. The theoretical basis for the interview studies was informed by theoretical frameworks from IT-adoption theory, where in particular the UTAUT model has provided the main basis for the analyses presented here. The results showed that the decisions to take the above technologies into use are made on three differ- ent levels: the individual level, the organizational level in the form of a company, and the organiza- tional level in the form of a project. The different patterns in adoption can to some part be explained by where the decisions are mainly taken. EDM is driven from the organisation/project level, EDI mainly from the organisation/company level, and BIM is driven by individuals pioneering the technique.

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The goal of the single building information model has existed for at least thirty years and various standards have been published leading up to the ten-year development of the Industry Foundation Classes. These have been initiatives from researchers, software developers and standards committees. Now large property owners are becoming aware of the benefits of moving IT tools from specific applications towards more comprehensive solutions. This study addresses the state of Building Information Models and the conditions necessary for them to become more widely used. It is a qualitative study based on information from a number of international experts and has asked a series of questions about the feasibility of BIMs, the conditions necessary for their success, and the role of standards with particular reference to the IFCs. Some key statements were distilled from the diverse answers received and indicate that BIM solutions appear too complex for many and may need to be applied in limited areas initially. Standards are generally supported but not applied rigorously and a range of these are relevant to BIM. Benefits will depend upon the building procurement methods used and there should be special roles within the project team to manage information. Case studies are starting to appear and these could be used for publicity. The IFCs are rather oversold and their complexities should be hidden within simple-to-use software. Inevitably major questions remain and property owners may be the key to answering some of these. A framework for presenting standards, backed up by case studies of successful projects, is the solution proposed to provide better information on where particular BIM standards and solutions should be applied in building projects.

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Triggered by the very quick proliferation of Internet connectivity, electronic document management (EDM) systems are now rapidly being adopted for managing the documentation that is produced and exchanged in construction projects. Nevertheless there are still substantial barriers to the efficient use of such systems, mainly of a psychological nature and related to insufficient training. This paper presents the results of empirical studies carried out during 2002 concerning the current usage of EDM systems in the Finnish construction industry. The studies employed three different methods in order to provide a multifaceted view of the problem area, both on the industry and individual project level. In order to provide an accurate measurement of overall usage volume in the industry as a whole telephone interviews with key personnel from 100 randomly chosen construction projects were conducted. The interviews showed that while around 1/3 of big projects already have adopted the use of EDM, very few small projects have adopted this technology. The barriers to introduction were investigated through interviews with representatives for half a dozen of providers of systems and ASP-services. These interviews shed a lot of light on the dynamics of the market for this type of services and illustrated the diversity of business strategies adopted by vendors. In the final study log files from a project which had used an EDM system were analysed in order to determine usage patterns. The results illustrated that use is yet incomplete in coverage and that only a part of the individuals involved in the project used the system efficiently, either as information producers or consumers. The study also provided feedback on the usefulness of the log files.

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Researchers within the fields of economic geography and organizational management have extensively studied learning and the prerequisites and impediments for knowledge transfer. This paper combines two discourses within the two subjects: the-communities-of-practice and the learning region approaches, merging them through the so-called ecology of knowledge-approach, which is used to examine the knowledge transfer from the House of Fabergé to the Finnish jewellery industry. We examine the pre-revolution St Petersburg jewellery cluster and the post-revolution Helsinki, and the transfer of knowledge between these two locations through the components of communities of people, institutions and industry. The paper shows that the industrial dynamics of the Finnish modern-day goldsmith industry was inherently shaped both through the transfer and the non-transfer of knowledge. It also contends that the “knowledge-economy” is not anchored in and exclusive for the high technology sector of the late 20th century.