456 resultados para 1455


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Phylogenetic inference from sequences can be misled by both sampling (stochastic) error and systematic error (nonhistorical signals where reality differs from our simplified models). A recent study of eight yeast species using 106 concatenated genes from complete genomes showed that even small internal edges of a tree received 100% bootstrap support. This effective negation of stochastic error from large data sets is important, but longer sequences exacerbate the potential for biases (systematic error) to be positively misleading. Indeed, when we analyzed the same data set using minimum evolution optimality criteria, an alternative tree received 100% bootstrap support. We identified a compositional bias as responsible for this inconsistency and showed that it is reduced effectively by coding the nucleotides as purines and pyrimidines (RY-coding), reinforcing the original tree. Thus, a comprehensive exploration of potential systematic biases is still required, even though genome-scale data sets greatly reduce sampling error.

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We compare three alternative methods for eliciting retrospective confidence in the context of a simple perceptual task: the Simple Confidence Rating (a direct report on a numerical scale), the Quadratic Scoring Rule (a post-wagering procedure), and the Matching Probability (MP; a generalization of the no-loss gambling method). We systematically compare the results obtained with these three rules to the theoretical confidence levels that can be inferred from performance in the perceptual task using Signal Detection Theory (SDT). We find that the MP provides better results in that respect. We conclude that MP is particularly well suited for studies of confidence that use SDT as a theoretical framework.

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The main question of my doctoral thesis is whether ufology and UFO experiences are or can be explained as religious phenomena. My research is theoretical in the sense that I combine and systematise cultural scientific knowledge concerning the religiosity of ufology and UFO experiences and complete this theoretical effort with empirical subject matter. The research material for my study consists of theoretical literature and empirical texts written by ufologists and those who have had UFO experiences. I defined the material in a way that it became full and extensive with regard to ufology, stories about UFO experiences and the cultural scientific literature concerning them. In addition, I present a source criticism for the literature because it is in part informal. The method is analysing and synthesising the material in the context of spiral of hermeneutic inferential process. Definitions of religion, ufology and UFO experience, developed by myself, serve as guide lines for the process. The conclusions of my research are as follows. For the most part, ufology and UFO experiences belong to the category of religion and only a fraction of these instances can be explained as something else, for example psychiatric phenomena. From the religious viewpoint I explain ufology and UFO experiences on four different but interlinked levels: historical, comparative, sociological and psychological. Historically ufology and UFO experiences include esoteristic, Christian and folk religious elements. In addition UFO experiences have significant similarities with folk religious stories and shamanistic experiences. From the perspective of the sociology, of religion ufology and UFO experiences can be analysed as products of our scientific and technological Western culture. Social crisis and social psychological group mechanisms affect the appearance of ufological ideas and UFO experiences. Psychologically, in the background of religious UFO experiences there can be found several factors, such as wishful thinking. Concerning UFO sightings these are misinterpretations of certain ordinary and some rare or exotic natural and technical phenomena. Intense UFO experiences, such as UFO abductions, are stimulated for the most part by hallucinations, sleep paralysis disorders, lively fantasies (in case of fantasy prone personalities) and false memories. In group cases social pressure, small group delusion and the guilt of exposing the true nature of a story come into play. A UFO experience can be traumatising because of certain inferential mechanisms and cognitive dissonance involved in the process of conversion as a UFO experiencer. UFO religiosity is a cross cultural, widespread and a significant field of phenomena, which can offer insight about religious developments in the future. However, UFO religiosity has not been studied extensively. This research is one effort to address this lack of documentation. The motivation behind my thesis was to make ufology and UFO experiences more understandable.

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Forty-four study sites were established in remnant woodland in the Burdekin River catchment in tropical north-east Queensland, Australia, to assess recent (decadal) vegetation change. The aim of this study was further to evaluate whether wide-scale vegetation 'thickening' (proliferation of woody plants in formerly more open woodlands) had occurred during the last century, coinciding with significant changes in land management. Soil samples from several depth intervals were size separated into different soil organic carbon (SOC) fractions, which differed from one another by chemical composition and turnover times. Tropical (C4) grasses dominate in the Burdekin catchment, and thus δ13C analyses of SOC fractions with different turnover times can be used to assess whether the relative proportion of trees (C3) and grasses (C4) had changed over time. However, a method was required to permit standardized assessment of the δ13C data for the individual sites within the 13 Mha catchment, which varied in soil and vegetation characteristics. Thus, an index was developed using data from three detailed study sites and global literature to standardize individual isotopic data from different soil depths and SOC fractions to reflect only the changed proportion of trees (C3) to grasses (C3) over decadal timescales. When applied to the 44 individual sites distributed throughout the Burdekin catchment, 64% of the sites were shown to have experienced decadal vegetation thickening, while 29% had remained stable and the remaining 7% had thinned. Thus, the development of this index enabled regional scale assessment and comparison of decadal vegetation patterns without having to rely on prior knowledge of vegetation changes or aerial photography.

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The point of departure in this dissertation was the practical safety problem of unanticipated, unfamiliar events and unexpected changes in the environment, the demanding situations which the operators should take care of in the complex socio-technical systems. The aim of this thesis was to increase the understanding of demanding situations and of the resources for coping with these situations by presenting a new construct, a conceptual model called Expert Identity (ExId) as a way to open up new solutions to the problem of demanding situations and by testing the model in empirical studies on operator work. The premises of the Core-Task Analysis (CTA) framework were adopted as a starting point: core-task oriented working practices promote the system efficiency (incl. safety, productivity and well-being targets) and that should be supported. The negative effects of stress were summarised and the possible countermeasures related to the operators' personal resources such as experience, expertise, sense of control, conceptions of work and self etc. were considered. ExId was proposed as a way to bring emotional-energetic depth into the work analysis and to supplement CTA-based practical methods to discover development challenges and to contribute to the development of complex socio-technical systems. The potential of ExId to promote understanding of operator work was demonstrated in the context of the six empirical studies on operator work. Each of these studies had its own practical objectives within the corresponding quite broad focuses of the studies. The concluding research questions were: 1) Are the assumptions made in ExId on the basis of the different theories and previous studies supported by the empirical findings? 2) Does the ExId construct promote understanding of the operator work in empirical studies? 3) What are the strengths and weaknesses of the ExId construct? The layers and the assumptions of the development of expert identity appeared to gain evidence. The new conceptual model worked as a part of an analysis of different kinds of data, as a part of different methods used for different purposes, in different work contexts. The results showed that the operators had problems in taking care of the core task resulting from the discrepancy between the demands and resources (either personal or external). The changes of work, the difficulties in reaching the real content of work in the organisation and the limits of the practical means of support had complicated the problem and limited the possibilities of the development actions within the case organisations. Personal resources seemed to be sensitive to the changes, adaptation is taking place, but not deeply or quickly enough. Furthermore, the results showed several characteristics of the studied contexts that complicated the operators' possibilities to grow into or with the demands and to develop practices, expertise and expert identity matching the core task. They were: discontinuation of the work demands, discrepancy between conceptions of work held in the other parts of organisation, visions and the reality faced by the operators, emphasis on the individual efforts and situational solutions. The potential of ExId to open up new paths to solving the problem of the demanding situations and its ability to enable studies on practices in the field was considered in the discussion. The results were interpreted as promising enough to encourage the conduction of further studies on ExId. This dissertation proposes especially contribution to supporting the workers in recognising the changing demands and their possibilities for growing with them when aiming to support human performance in complex socio-technical systems, both in designing the systems and solving the existing problems.

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Invitation to attend: On behalf of the organising committee of the 16th Australian Weeds Conference, we cordially invite you to attend this biannual conference to be held in Cairns, Australia, 19-22 May 2008. The conference will be hosted by the Weed Society of Queensland and has the theme of ‘Weed Management 2008 – hot topics in the tropics’. The conference will showcase recent advances in weed science, extension and policy across Australian and international communities and landscapes. The program for the conference includes plenary, oral, and poster sessions and trade exhibitors. The conference will appeal to anyone involved in weed R & D, management and extension and will be a great opportunity to build new networks and explore existing ones. Michael Widderick (conference chair)

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The purpose of this research was to evaluate the special vocational training programme, which aimed at enhancing the pupils with autism spectrum to prepare themselves for work and independent life. The vocational training programme is based on TEACCH (Treatment and Education of Autistic and Related Communication handicapped CHildren), which takes into account the autism spectrum disorders and autistic behaviour. TEACCH is based on the principles of structured teaching, functional teaching and preparation training for work and independent life. The TEACCH has been adapted to Finnish society and the educational system. Treatment programmes were individually designed for each student´s educational needs. There is also an important role for the AAPEP rating scale (Adolescent and Adult Psychoeducational Profile). The AAPEP has been the major tool for planning and following the courses. The AAPEP is an assessment instrument designed by the TEACCH programme, and it is used to provide an evaluation of current and potential skills. The AAPEP contains three scales: a direct observation scale, a home scale and a school / work scale. The AAPEP includes six test variables: vocational skills, independent functions, functional communication, interpersonal behaviour, vocational behaviour and leisure skills; these are evaluated at three levels: pass, emerge and fail. The subjects were 49 students (65% male and 35 % female) with autism spectrum, who have been followed and tested several times, also one year after the vocational training. The design is therefore a longitudinal one. The research data were collected 1997-2004 using the AAPEP rating scales. The teachers have used the AAPEP scales and the codings have been checked by the researcher. The results of the principal component analysis (PCA) suggested that the structure of AAPEP rating scales works quite well as a hypothesis. The factor structure of the scales of the AAPEP was almost the same in these data as in the original publications. The learning-and-changes results showed that learning is a slow process, but that there were also intended changes in several AAPEP areas. The Cohen´s kappa was used as an effect-size measure and the most important result of this research showed that the student´s skills were developing on a school / work scale; vocational skills variable (0,34), vocational behaviour variable (0,28), leisure skills variable (0,26) and on a direct observation scale; interpersonal behaviour variable (0,21). On a home scale skills of some students were developing negatively and also that effect-size was small. The results showed that the students´ vocational skills and vocational behaviour will continue to develop after school in many areas. There were differences between scales. The result of this research shows that the student´s skills were developing significantly in 3 of 48 variables on a direct observation scale and also on a home scale. On a school / work scale student´s skills were developing significantly in 17 of 48 variables. This result implies that students can do the work without extra assistance if there exist continuing supports for the skills after the vocational training. The fully independent life of students will be difficult, because their independent functions, functional communications and leisure skills regressed after the schooling. This seems to indicate that they will not manage their daily life without support. The students and their parents said that the treatment programmes were individually designed for each student s educational needs, and that they were satisfied with the programmes and services. Generally, it can be concluded that vocational special education can be developed for pupils with autistic syndrome and the detailed teaching can be done using TEACCH principles and applying the tool of AAPEP.

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Electrically active deep levels related to nickel in silicon are studied under different diffusion conditions, quenching modes, and annealing conditions. The main nickel-related level is at Ev+0.32 eV. Levels at Ev+0.15 and Ev+0.54 eV are not related to nickel while those at Ev+0.50 and Ev+0.28 eV may be nickel related. Their concentrations depend on the quenching mode. There is no nickel-related level in the upper half of the band gap. The complicated annealing behavior of the main nickel-related level is explained on the basis of the formation and dissociation of a nickel-vacany complex. Journal of Applied Physics is copyrighted by The American Institute of Physics.

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Total hip replacement is the golden standard treatment for severe osteoarthritis refractory for conservative treatment. Aseptic loosening and osteolysis are the major long-term complications after total hip replacement. Foreign body giant cells and osteoclasts are locally formed around aseptically loosening implants from precursor cells by cell fusion. When the foreign body response is fully developed, it mediates inflammatory and destructive host responses, such as collagen degradation. In the present study, it was hypothesized that the wear debris and foreign body inflammation are the forces driving local osteoclast formation, peri-implant bone resorption and enhanced tissue remodeling. Therefore the object was to characterize the eventual expression and the role of fusion molecules, ADAMs (an abbreviation for A Disintegrin And Metalloproteinase, ADAM9 and ADAM12) in the fusion of progenitor cells into multinuclear giant cells. For generation of such cells, activated macrophages trying to respond to foreign debris play an important role. Matured osteoclasts together with activated macrophages mediate bone destruction by secreting protons and proteinases, including matrix metalloproteinases (MMPs) and cathepsin K. Thus this study also assessed collagen degradation and its relationship to some of the key collagenolytic proteinases in the aggressive synovial membrane-like interface tissue around aseptically loosened hip replacement implants. ADAMs were found in the interface tissues of revision total hip replacement patients. Increased expression of ADAMs at both transcriptional and translational levels was found in synovial membrane-like interface tissue of revision total hip replacement (THR) samples compared with that in primary THR samples. These studies also demonstrate that multinucleate cell formation from monocytes by stimulation with macrophage-colony stimiulating factor (M-CSF) and receptor activator of nuclear factor kappa B ligand (RANKL) is characterized by time dependent changes of the proportion of ADAMs positive cells. This was observed both in the interface membrane in patients and in two different in vitro models. In addition to an already established MCS-F and RANKL driven model, a new virally (parainfluenza 2) driven model (of human salivary adenocarcinoma (HSY) cells or green monkey kidney (GMK) cells) was developed to study various fusion molecules and their role in cell fusion in general. In interface membranes, collagen was highly degraded and collagen degradation significantly correlated with the number of local cells containing collagenolytic enzymes, particularly cathepsin K. As a conclusion, fusion molecules ADAM9 and ADAM12 seem to be dynamically involved in cell-cell fusion processes and multinucleate cell formation. The highly significant correlation between collagen degradation and collagenolytic enzymes, particularly cathepsin K, indicates that the local acidity of the interface membrane in the pathologic bone and soft tissue destruction. This study provides profound knowledge about cell fusion and mechanism responsible for aseptic loosening as well as increases knowledge helpful for prevention and treatment.

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The aim of the present research was to examine the validity of the RAND-36 measure of health-related quality of life among the working age rehabilitation clients. The research included two cross-sectional studies and one follow-up study. The subjects of the first study (n = 794) participated in the first period of the five following types of rehabilitation: occupationally oriented medical rehabilitation, musculoskeletal rehabilitation, medical rehabilitation for job burnout, rehabilitation for supporting the work ability and capacity of disabled subjects (vocational rehabilitation) and individualized rehabilitation between October 2000 and October 2001. The subjects of the second study (n = 990) participated in the same rehabilitation during their first rehabilitation period between May 2007 and May 2008. The first subjects participated in a follow-up period no later than May 2003 with the exception of the individual rehabilitation clients (n = 588). Based on the ICF classification, the RAND-36 provides a diverse measure of the health-related quality of life and of the capacity for subjective, perceived physical and psycho-social functioning. The construct properties of the RAND-36 measure proved to be very consistent on the basis of both the cluster and confirmatory factor analyses. At the group level, the RAND-36 measure was shown to be illustrative and sensitive in differentiating the clients’ rehabilitation needs. The results of cluster analyses with the two cross-sectional data indicated a consistent five-cluster solution of rehabilitation groups on the basis of the eight subscales of health-related quality of life. Each of these clusters represented a clear difference in their need for rehabilitation. The RAND-36 measure proved to be sensitive to change. The changes observed in the pre- and post-conditions in relation to all the subscales of quality of life were statistically significant. Depending on the rehabilitation type, different changes in the subscales of the measure were observed, and these changes corresponded to the different emphasis and goals of the specific type of rehabilitation intervention. Similarly, changes in the subscales of the measure were observed in relation to the RAND groups formed by cluster analysis, which were logical and corresponded to the problem profiles of these groups. The confirmatory factor analysis indicated a two-factor solution: an index of the capacity for physical functioning (self-rated general health, bodily pain, physical functioning, physical role functioning) and an index of the capacity for psycho-social functioning (psychological well-being, social functioning, psychological role functioning and energy). These two indices describing functional capacity proved also to be sensitive to change. This two-factor solution seems to be usable for group level analyses when assessing the effects of rehabilitation. The moderately strong correlation between the RAND-36 and work ability index suggests that they partly measure the same phenomenon: perceived health-related quality of life, subjective capacity for activity and perceived work ability have strong links. As expected, the capacity for physical functioning had a stronger correlation with work ability index than with the capacity for psycho-social functioning. According to the present research, the RAND-36 measure can be considered as a screening method for rehabilitation orientation in relation to rehabilitation needs and as a follow-up measure for the health-related quality of life among the working age clients. The RAND-36 measure is also shown to be a useful instrument in estimating the benefits of rehabilitation as well as in effectiveness research.

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Tässä väitöskirjassa esitellään langattomien maanalaisten peltotiedustelijoiden järjestelmän tavoitteet ja rajoitukset. Tarkoitus oli kehittää käytännön viljelyyn sovellettava pellon seurantajärjestelmä, sillä reaaliaikaisen kosteus- ja lämpötilatiedon keruulaitteiden puuttuminen haittaa viljelytoimenpiteiden suunnittelua. Mittaus-aineistosta voi tehdä sekä havaintoja pellon ominaisuuksista että muutoksista niissä. Tulevaisuudessa tiedustelijalla saatetaan voida mitata ravinteita tai kemikaaleja. Kun peltotiedustelijan 869 MHz:n radioaalto saavuttaa vastaanottoantennin, on 1) maa-aines vaimentanut sitä; 2) osa aallosta heijastunut rajapinnoilta; 3) pellosta ulos taittuva aalto hajaantunut ja; 4) aallon intensiteetti alentunut etäisyyden kasvaessa. Maan sähkökenttäkäyttäytymistä kuvaava permittiivisyys on kompleksinen suure, jonka reaaliosa kuvaa varautumiskykyä (polarisoitumista) ja imaginaariosa häviöllisyyttä (sähkönjohtavuutta). Pellon pinnassa aalto on pallomainen, joten heijastumisen lisäksi hajaannuttaa taittuminen suurilla taitekulmilla sen tehoa. Tiedustelijan prototyyppiä varten kehitettiin maa-aineksessa toimivat antennit, joiden taajuuskaistat kattoivat ne aallonpituudet, jotka 869 MHz:n radioaalto saa kuivassa ja märässä mullassa, sillä aallon etenemisnopeus ja pituus muuttuvat maan kosteudesta riippuen. Vaimennusmallin testausmittauksiin tehtiin discone-antenni, ja tiedustelijaa varten piirilevytekniikalla pienikokoinen elliptinen monopoliantenni, jonka piirikortille ladottiin myös tiedustelijan elektroniikka. Multalaatikkoon upotettujen antennien säteilyominaisuudet määritettiin piirianalysaattorilla heijastusvaimennusmittauksin. Elektroniikkasuunnittelun tavoitteita oli pieni koko ja pitkä toimintaikä. Näihin päästiin komponenttivalinnoilla sekä ohjelmoinnin keinoin. Tiedustelija teki mittaukset ja lähetti tulokset 10 min välein ja sen keskivirrankulutus oli 4,2 uA käytettäessä 3 V:n paristoa, jonka 1800 mAh kapasiteetti riittäisi huonollakin hyötysuhteella yli 10 vuodeksi. Vuoden mittaisen 12 prototyypin käytön perusteella voidaan kantamaa parantaa yli nykyisen 200 m:n ilman käyttöiän lyhentymistä 1) nostamalla laitteen lähetystehoa ja pariston käyttöastetta lisäkomponenteilla; 2) parantamalla vastaanottoantennin vahvistusta; 3) pidentämällä lähetysten jaksoa; 4) ohjelmoimalla tiedustelija suodattamaan mittaustietoja ja; 5) koodaamalla useita tuloksia samaan lähetteeseen. Järjestelmän ja mittaustulosten käytettävyyttä voidaan parantaa paikantamalla tiedustelijoiden syvyydet aaltoilevan lämpötilan vaihe-erojen perusteella ja ohjelmoimalla tiedustelijaan opastava asennustoiminto. Lisäksi maahan asennetun tiedustelijan toimintaparametrit tai jopa koko ohjelmisto voidaan vaihtaa langattomasti. Vastaanottoasemat matkapuhelinmastoissa voisivat vastaanottaa viestejä parin kilometrin säteeltä. Koostettu aineisto maaperäsimulaattoreihin yhdistettynä antaisi kuvan alueellisesta tilanteesta ja viljelijän omille lohkoille sijoitetut tiedustelijat korjauspisteitä keskiarvosta.

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The aim of this thesis is to develop a fully automatic lameness detection system that operates in a milking robot. The instrumentation, measurement software, algorithms for data analysis and a neural network model for lameness detection were developed. Automatic milking has become a common practice in dairy husbandry, and in the year 2006 about 4000 farms worldwide used over 6000 milking robots. There is a worldwide movement with the objective of fully automating every process from feeding to milking. Increase in automation is a consequence of increasing farm sizes, the demand for more efficient production and the growth of labour costs. As the level of automation increases, the time that the cattle keeper uses for monitoring animals often decreases. This has created a need for systems for automatically monitoring the health of farm animals. The popularity of milking robots also offers a new and unique possibility to monitor animals in a single confined space up to four times daily. Lameness is a crucial welfare issue in the modern dairy industry. Limb disorders cause serious welfare, health and economic problems especially in loose housing of cattle. Lameness causes losses in milk production and leads to early culling of animals. These costs could be reduced with early identification and treatment. At present, only a few methods for automatically detecting lameness have been developed, and the most common methods used for lameness detection and assessment are various visual locomotion scoring systems. The problem with locomotion scoring is that it needs experience to be conducted properly, it is labour intensive as an on-farm method and the results are subjective. A four balance system for measuring the leg load distribution of dairy cows during milking in order to detect lameness was developed and set up in the University of Helsinki Research farm Suitia. The leg weights of 73 cows were successfully recorded during almost 10,000 robotic milkings over a period of 5 months. The cows were locomotion scored weekly, and the lame cows were inspected clinically for hoof lesions. Unsuccessful measurements, caused by cows standing outside the balances, were removed from the data with a special algorithm, and the mean leg loads and the number of kicks during milking was calculated. In order to develop an expert system to automatically detect lameness cases, a model was needed. A probabilistic neural network (PNN) classifier model was chosen for the task. The data was divided in two parts and 5,074 measurements from 37 cows were used to train the model. The operation of the model was evaluated for its ability to detect lameness in the validating dataset, which had 4,868 measurements from 36 cows. The model was able to classify 96% of the measurements correctly as sound or lame cows, and 100% of the lameness cases in the validation data were identified. The number of measurements causing false alarms was 1.1%. The developed model has the potential to be used for on-farm decision support and can be used in a real-time lameness monitoring system.

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Flax and hemp have traditionally been used mainly for textiles, but recently interest has also been focused on non-textile applications. Microbial quality throughout the whole processing chain of bast fibres has not previously been studied. This study concentrates on the microbial quality and possible microbial risks in the production chain of hemp and flax fibres and fibrous thermal insulations. In order to be able to utilize hemp and flax fibres, the bast fibres must be separated from the rest of the plant. Non-cellulosic components can be removed with various pretreatment processes, which are associated with a certain risk of microbial contamination. In this study enzymatic retting and steam explosion (STEX) were examined as pretreatment processes. On the basis of the results obtained in this study, the microbial contents on stalks of both plants studied increased at the end of the growing season and during the winter. However, by processing and mechanical separation it is possible to produce fibres containing less moulds and bacteria than the whole stem. Enzymatic treatment encouraged the growth of moulds in fibres. Steam explosion reduced the amount of moulds in fibres. Dry thermal treatment used in this study did not markedly reduce the amount of microbes. In this project an emission measurement chamber was developed which was suitable for measurements of emissions from both mat type and loose fill type insulations, and capable of interdisciplinary sampling. In this study, the highest amounts of fungal emissions were in the range of 10^3 10^5 cfu/m^3 from the flax and hemp insulations at 90% RH of air. The fungal emissions from stone wool, glass wool and recycled paper insulations were below 10^2 cfu/m^3 even at 90% RH. Equally low values were obtained from bast fibrous materials in lower humidities (at 30% and 80% RH of air). After drying of moulded insulations at 30% RH, the amounts of emitted moulds were in all cases higher compared to the emissions at 90% RH before drying. The most common fungi in bast fibres were Penicillium and Rhizopus. The widest variety of different fungi was in the untreated hemp and linseed fibres and in the commercial loose-fill flax insulation. Penicillium, Rhizopus and Paecilomyces were the most tolerant to steam explosion. According to the literature, the most common fungi in building materials and indoor air are Penicillium, Aspergillus and Cladosporium, which were all found in some of the bast fibre materials in this study. As organic materials, hemp and flax fibres contain high levels of nutrients for microbial growth. The amount of microbes can be controlled and somewhat decreased by the processing methods presented.

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Plastic surfaces are a group of materials used for many purposes. The present study was focused on methods for investigation of surface topography, wearing and cleanability of polyvinyl chloride (PVC) model surfaces and industrial plastic surfaces. Contact profilometry, scanning electron microscopy (SEM) and atomic force microscopy (AFM) are powerful methods for studying the topography of plastic surfaces. Although they have their own limitations, they are together an effective tool providing useful information on surface topography, especially when studying laboratory-made PVC model surfaces with known chemical compositions and structures. All examined laboratory-made PVC plastic surfaces examined in this work could be considered as smooth according to both AFM and profilometer measurements because height differences are in the nanoscale on every surface. Industrial plastic surfaces are a complex group of materials because of their chemical and topographical heterogeneity, but they are nevertheless important reference materials when developing cleaning and wearing methods. According to the results of this study the Soiling and Wearing Drum and the Frick-Taber methods are very useful when simulating three-body wearing of plastic surfaces. Both the investigated wearing methods can be used to compare the wearing of different plastic materials using appropriate evaluation methods of wearing and industrial use. In this study, physical methods were developed and adapted from other fields of material research to cleanability studies. The thesis focuses on the methodology for investigating the cleanability of plastic surfaces under realistic conditions, where surface topography and the effect of wear cleanability were among the major topics. A colorimetric method proved to be suitable for examining the cleanability of the industrial plastic surfaces. The results were utilized to evaluate the relationship between cleanability and the surface properties of plastic surfaces. The devices and methods used in the work can be utilized both in material research and product development.

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The aim of this thesis was to develop measurement techniques and systems for measuring air quality and to provide information about air quality conditions and the amount of gaseous emissions from semi-insulated and uninsulated dairy buildings in Finland and Estonia. Specialization and intensification in livestock farming, such as in dairy production, is usually accompanied by an increase in concentrated environmental emissions. In addition to high moisture, the presence of dust and corrosive gases, and widely varying gas concentrations in dairy buildings, Finland and Estonia experience winter temperatures reaching below -40 ºC and summer temperatures above +30 ºC. The adaptation of new technologies for long-term air quality monitoring and measurement remains relatively uncommon in dairy buildings because the construction and maintenance of accurate monitoring systems for long-term use are too expensive for the average dairy farmer to afford. Though the documentation of accurate air quality measurement systems intended mainly for research purposes have been made in the past, standardised methods and the documentation of affordable systems and simple methods for performing air quality and emissions measurements in dairy buildings are unavailable. In this study, we built three measurement systems: 1) a Stationary system with integrated affordable sensors for on-site measurements, 2) a Wireless system with affordable sensors for off-site measurements, and 3) a Mobile system consisting of expensive and accurate sensors for measuring air quality. In addition to assessing existing methods, we developed simplified methods for measuring ventilation and emission rates in dairy buildings. The three measurement systems were successfully used to measure air quality in uninsulated, semi-insulated, and fully-insulated dairy buildings between the years 2005 and 2007. When carefully calibrated, the affordable sensors in the systems gave reasonably accurate readings. The spatial air quality survey showed high variation in microclimate conditions in the dairy buildings measured. The average indoor air concentration for carbon dioxide was 950 ppm, for ammonia 5 ppm, for methane 48 ppm, for relative humidity 70%, and for inside air velocity 0.2 m/s. The average winter and summer indoor temperatures during the measurement period were -7º C and +24 ºC for the uninsulated, +3 ºC and +20 ºC for the semi-insulated and +10 ºC and +25 ºC for the fully-insulated dairy buildings. The measurement results showed that the uninsulated dairy buildings had lower indoor gas concentrations and emissions compared to fully insulated buildings. Although occasionally exceeded, the ventilation rates and average indoor air quality in the dairy buildings were largely within recommended limits. We assessed the traditional heat balance, moisture balance, carbon dioxide balance and direct airflow methods for estimating ventilation rates. The direct velocity measurement for the estimation of ventilation rate proved to be impractical for naturally ventilated buildings. Two methods were developed for estimating ventilation rates. The first method is applicable in buildings in which the ventilation can be stopped or completely closed. The second method is useful in naturally ventilated buildings with large openings and high ventilation rates where spatial gas concentrations are heterogeneously distributed. The two traditional methods (carbon dioxide and methane balances), and two newly developed methods (theoretical modelling using Fick s law and boundary layer theory, and the recirculation flux-chamber technique) were used to estimate ammonia emissions from the dairy buildings. Using the traditional carbon dioxide balance method, ammonia emissions per cow from the dairy buildings ranged from 7 g day-1 to 35 g day-1, and methane emissions per cow ranged from 96 g day-1 to 348 g day-1. The developed methods proved to be as equally accurate as the traditional methods. Variation between the mean emissions estimated with the traditional and the developed methods was less than 20%. The developed modelling procedure provided sound framework for examining the impact of production systems on ammonia emissions in dairy buildings.