985 resultados para Forced eruption


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The properties of the paper surface play a crucial role in ensuring suitable quality and runnability in various converting and finishing operations, such as printing. Plasma surface modification makes it possible to modify the surface chemistry of paper without altering the bulk material properties. This also makes it possible to investigate the role of the surface chemistry alone on printability without influencing the porous structure of the pigment-coated paper. Since the porous structure of a pigment coating controls both ink setting and optical properties, surface chemical changes created by a plasma modification have a potential to decouple these two effects and to permit a better optimization of them both. The aim of this work was to understand the effects of plasma surface modification on paper properties, and how it influences printability in the sheet-fed offset process. The objective was to broaden the fundamental understanding of the role of surface chemistry on offset printing. The effects of changing the hydrophilicity/ hydrophobicity and the surface chemical composition by plasma activation and plasma coatings on the properties of coated paper and on ink-paper interactions as well as on sheet-fed offset print quality were investigated. In addition, the durability of the plasma surface modification was studied. Nowadays, a typical sheet-fed offset press also contains units for surface finishing, for example UVvarnishing. The role of the surface chemistry on the UV-varnish absorption into highly permeable and porous pigment-coated paper was also investigated. With plasma activation it was possible to increase the surface energy and hydrophilicity of paper. Both polar and dispersion interactions were found to increase, although the change was greater in the polar interactions due to induced oxygen molecular groups. The results indicated that plasma activation takes place particularly in high molecular weight components such as the dispersion chemicals used to stabilize the pigment and latex particles. Surface composition, such as pigment and binder type, was found to influence the response to the plasma activation. The general trend was that pilot-scale treatment modified the surface chemistry without altering the physical coating structure, whereas excessive laboratory-scale treatment increased the surface roughness and reduced the surface strength, which led to micro-picking in printing. It was shown that pilot-scale plasma activation in combination with appropriate ink oils makes it possible to adjust the ink-setting rate. The ink-setting rate decreased with linseed-oil-based inks, probably due to increased acid-base interactions between the polar groups in the oil and the plasma-treated paper surface. With mineral-oil-based inks, the ink setting accelerated due to plasma activation. Hydrophobic plasma coatings were able to reduce or even prevent the absorption of dampening water into pigmentcoated paper, even when the dampening water was applied under the influence of nip pressure. A uniform hydrophobic plasma coating with sufficient chemical affinity with ink gave an improved print quality in terms of higher print density and lower print mottle. It was also shown that a fluorocarbon plasma coating reduced the free wetting of the UV-varnish into the highly permeable and porous pigment coating. However, when the UV-varnish was applied under the influence of nip pressure, which leads to forced wetting, the role of the surface chemical composition seems to be much less. A decay in surface energy and wettability occurred during the first weeks of storage after plasma activation, after which it leveled off. However, the oxygen/carbon elemental ratio did not decrease as a function of time, indicating that ageing could be caused by a re-orientation of polar groups or by a contamination of the surface. The plasma coatings appeared to be more stable when the hydrophobicity was higher, probably due to fewer interactions with oxygen and water vapor in the air.

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The flow of information within modern information society has increased rapidly over the last decade. The major part of this information flow relies on the individual’s abilities to handle text or speech input. For the majority of us it presents no problems, but there are some individuals who would benefit from other means of conveying information, e.g. signed information flow. During the last decades the new results from various disciplines have all suggested towards the common background and processing for sign and speech and this was one of the key issues that I wanted to investigate further in this thesis. The basis of this thesis is firmly within speech research and that is why I wanted to design analogous test batteries for widely used speech perception tests for signers – to find out whether the results for signers would be the same as in speakers’ perception tests. One of the key findings within biology – and more precisely its effects on speech and communication research – is the mirror neuron system. That finding has enabled us to form new theories about evolution of communication, and it all seems to converge on the hypothesis that all communication has a common core within humans. In this thesis speech and sign are discussed as equal and analogical counterparts of communication and all research methods used in speech are modified for sign. Both speech and sign are thus investigated using similar test batteries. Furthermore, both production and perception of speech and sign are studied separately. An additional framework for studying production is given by gesture research using cry sounds. Results of cry sound research are then compared to results from children acquiring sign language. These results show that individuality manifests itself from very early on in human development. Articulation in adults, both in speech and sign, is studied from two perspectives: normal production and re-learning production when the apparatus has been changed. Normal production is studied both in speech and sign and the effects of changed articulation are studied with regards to speech. Both these studies are done by using carrier sentences. Furthermore, sign production is studied giving the informants possibility for spontaneous speech. The production data from the signing informants is also used as the basis for input in the sign synthesis stimuli used in sign perception test battery. Speech and sign perception were studied using the informants’ answers to questions using forced choice in identification and discrimination tasks. These answers were then compared across language modalities. Three different informant groups participated in the sign perception tests: native signers, sign language interpreters and Finnish adults with no knowledge of any signed language. This gave a chance to investigate which of the characteristics found in the results were due to the language per se and which were due to the changes in modality itself. As the analogous test batteries yielded similar results over different informant groups, some common threads of results could be observed. Starting from very early on in acquiring speech and sign the results were highly individual. However, the results were the same within one individual when the same test was repeated. This individuality of results represented along same patterns across different language modalities and - in some occasions - across language groups. As both modalities yield similar answers to analogous study questions, this has lead us to providing methods for basic input for sign language applications, i.e. signing avatars. This has also given us answers to questions on precision of the animation and intelligibility for the users – what are the parameters that govern intelligibility of synthesised speech or sign and how precise must the animation or synthetic speech be in order for it to be intelligible. The results also give additional support to the well-known fact that intelligibility in fact is not the same as naturalness. In some cases, as shown within the sign perception test battery design, naturalness decreases intelligibility. This also has to be taken into consideration when designing applications. All in all, results from each of the test batteries, be they for signers or speakers, yield strikingly similar patterns, which would indicate yet further support for the common core for all human communication. Thus, we can modify and deepen the phonetic framework models for human communication based on the knowledge obtained from the results of the test batteries within this thesis.

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Maritime transports are very essential for Finland as over 80% of the foreign trade in the country is seaborne and possibilities to carry out these transports by are limited. Any disruption in maritime transports has negative consequences to many sectors in the Finnish economy. Maritime transport thus represents critical infrastructure for Finland. This report focuses on the importance of maritime transports on security of supply in Finland and for the so called critical industries in particular. The report summarizes the results of the Work Package 2 of the research project STOCA – “Study of cargo flows in the Gulf of Finland in emergency situations”. The aim of the research was to analyze the cargo flows and infrastructure that are vital for maintaining security of supply in Finland, as well as the consequences of disruptions in the maritime traffic for the Finnish critical industries and for the Finnish society. In the report we give a presentation of the infrastructure and transport routes which are critical for maintaining security of supply in Finland. We discuss import dependency of the critical industries, and the importance of the Gulf of Finland ports for Finland. We assess vulnerabilities associated with the critical material flows of the critical industries, and possibilities for alternative routings in case either one or several of the ports in Finland would be closed. As a concrete example of a transport disruption we analyze the consequences of the Finnish stevedore strike at public ports (4.3.–19.3.2010). The strike stopped approximately 80% of the Finnish foreign trade. As a result of the strike Finnish companies could not export their products and/or import raw materials, components and spare parts, or other essential supplies. We carried out personal interviews with representatives of the companies in Finnish critical industries to find out about the problems caused by the strike, how companies carried out they transports and how they managed to continue their operations during the strike. Discussions with the representatives of the companies gave us very practical insights about companies’ preparedness towards transport disruptions in general. Companies in the modern world are very vulnerable to transport disruptions because companies regardless of industries have tried to improve their performance by optimizing their resources and e.g. by reducing their inventory levels. At the same time they have become more and more dependent on continuous transports. Most companies involved in foreign trade have global operations and global supply chains, so any disruption anywhere in the world can have an impact on the operations of the company causing considerable financial loss. The volcanic eruption in Iceland in April 2010 stopping air traffic in the whole Northern Europe and most recently the earth quake causing a tsunami in Japan in March 2011 are examples of severe disruptions causing considerable negative impacts to companies’ supply chains. Even though the Finnish stevedore strike was a minor disruption compared to the natural catastrophes mentioned above, it showed the companies’ vulnerability to transport disruptions very concretely. The Finnish stevedore strike gave a concrete learning experience of the importance of preventive planning for all Finnish companies: it made them re-think their practical preparedness towards transport risks and how they can continue with their daily operations despite the problems. Many companies realized they need to adapt their long-term countermeasures against transport disruptions. During the strike companies did various actions to secure their supply chains. The companies raised their inventory levels before the strike began, they re-scheduled or postponed their deliveries, shifted customer orders between production plants among their company’s production network or in the extreme case bought finished products from their competitor to fulfil their customers’ order. Our results also show that possibilities to prepare against transport disruptions differ between industries. The Finnish society as a whole is very dependent on imports of energy, various raw materials and other supplies needed by the different industries. For many of the Finnish companies in the export industries and e.g. in energy production maritime transport is the only transport mode the companies can use due to large volumes of materials transported or due to other characteristics of the goods. Therefore maritime transport cannot be replaced by any other transport mode. In addition, a significant amount of transports are concentrated in certain ports. From a security of supply perspective attention should be paid to finding ways to decrease import dependency and ensuring that companies in the critical industries can ensure the continuity of their operations.

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Sustainability is the aim of forest management and forest regulation in many countries. Accordingly, forest management has been steered towards more environmentally friendly methods and new regulatory instruments have been introduced. At the same time, wood trade and forest industry have become a global business. Even if the importance of national forest legislation has not decreased, it has been widely acknowledged that national regulation of forest management is no longer sufficient. The movement of goods does not acknowledge boundaries, even though most negative environmental and social consequences stay in the country of origin of wood and other raw materials. As a partial solution to this dilemma, different kinds of regulations have been developed. Various forest certification schemes and wood trade regulation in the EU (995/2010) are examples of efforts to prevent illegal logging and unsustainable forestry. The Finland-based forest industry is to a varying extent dependent on wood trade from Russia. Especially in the 1990‟s, ethical questions concerning import of wood from Russian old growth forests near the Finnish border were widely discussed. Consequently, forest industry enterprises have developed systems to trace the origin of wood and to buy certified wood from Russia. The aim of the research has been to evaluate Finnish and Russian forest regulations in order to investigate what kind of forest management these regulations enhance, and to what extent ecologically sustainable forest management has been integrated into different forms of regulation. I have examined Finnish and Russian forest regulation in four separate articles based on the topics of the Russian Forest Code, forest certification and other voluntary forest protection measures in Russia, Finnish forest certification and Finnish forest legislation. One objective has been to analyse the roles voluntary forest certification plays in promoting sustainable forest management in different countries. In my research, I have mainly concentrated on ecological sustainability and protection of biodiversity, although other aspects of sustainable forest management have been touched upon in different articles. In the following I shall conclude the findings of my research. When the current Russian Forest Code (2006) was being adopted, the main emphasis was not on ecological issues, but on reorganizing forest governance. The role of ecological requirements was even slightly diminished during the legislative reform. There are, nevertheless, still stipulations aiming at ecological sustainability, such as the division of forests into different forest management categories and various protection zones. In 2000, FSC forest certification arrived in Russia, at present covering already 28 million hectares of forests. The PEFC scheme is now in use as well, but to a much lesser extent. If properly implemented, Russian forest certification schemes clearly improve the level of ecological and social sustainability of forestry in Russia. Certification criteria, however, are partly in conflict with the Russian forest legislation and certified enterprises have been forced to pay fines or to negotiate with forest authorities. This clearly indicates that even if Russian forest legislation has otherwise been liberalized to a certain extent, some significant paternalism still exists. Voluntary, hands-on biodiversity protection measures are not valued, and they are not part of the official protection policies as in many other countries. However, there have been some regional solutions to this dilemma. In the Republic of Karelia forest authorities have approved a set of forest biodiversity protection rules created by a local NGO and a forest industry enterprise. By following these local rules, an enterprise can avoid fines for protection measures. The current Finnish Forest Act was adopted in 1996. It brought forest legislation into a new era as some ecological aspects were integrated into forest legislation. The various soft-law forest management recommendations further increased the level of biodiversity protection. My evaluation of the overall legitimacy of the Finnish forest legislation and forest management paradigm revealed, however, several problematic issues. As part of this study I analysed the history of the current forest management paradigm. This analysis revealed the path dependency which still hinders the protection of biodiversity and clearly decreases the general legitimacy of forest management. Due to several historical reasons only even-structured forest management based on clear cuts has for decades been officially approved in Finland. Due to increasing demands of forest owners the legislation is finally being revised. Yet, the official approval of uneven-structured forest management would not be enough to fully improve ecological, social and cultural legitimacy. The latest ecological theories and knowledge of endangered species should be taken into account in the on-going reform of forest legislation as well as the modernisation. Forest legislation is one of the very few spheres of Finnish environmental legislation where openness and participation are still considered a threat. The first Finnish forest certification scheme, PEFC, was established in 2000. It now covers more than 20 million hectares, about 95% of the forests in Finland. PEFC Finland does not require a higher level of biodiversity protection than the recommendations by Tapio (the Development Centre for Forestry), but certification has unified forest management practices and requires more protection measures than mere forest legislation. The study suggests that in Finland PEFC has not functioned as an instrument which would substantially improve the level of forest management. Rather it has supported the status quo of the forest sector. While the ecological and social responsibility of Finland-based forest corporations was one impetus for this research, I want to conclude that there are problems related to forest legislation and non-state regulation in both Finland and Russia. If an enterprise buying wood from Russia buys only certified wood, and carefully avoids wood coming from high conservation value forests that are either ecologically or socially valuable, it can be claimed to be as sustainably produced as in Finland. However, there must be continuous scrutiny of the circumstances. In Russia, the level of the compliance of certification criteria varies considerably, and there are vast unprotected invaluable forest areas. The utilisation of these areas should not be based on short-sighted decisions or lack of consensus among stakeholders.

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This thesis examined packaging inks suitable for folding cartons used in food packaging. The recent cases of compounds migrating from packaging inks into packed food, have forced the packaging ink manufacturers to develop inks that do not include substances at a level, that may pose a risk to the health of a consumer or to the quality of packed food. Food packaging is a sensitive area and subject to extensive legislation. This research presents the current situation on regulatory documents that can be used to demonstrate the safety of packaging inks used in food packaging. In the research, data was also collected on the available packaging inks for food packaging in packaging ink market. Test printing was performed with five printing inks and three varnishes on Ensocoat board, produced by Stora Enso. Tests results regarding print quality, runnability, sensory properties and migration were analysed. The packaging inks with the finest performance in the tests were ultra violet curing printing ink and varnish. The results showed that ultra violet curing printing technology in food contact applications is an important research area, with further research possibly being able to redeem the UV technologies' bad reputation within the packaging supply chain.

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The Kvarken Archipelago is Finland’s first Unesco Natural Heritage Site. The story of the Kvarken Archipelago began about 10.000 years ago when the melting of the continental ice sheet as it retreated gave rise to this unique archipelago. The land once forced down by the mass of ice is now gradually rising and continuously creating new landscapes. People, animals and plants have learnt to adjust to their changing conditions in exceptional ways. The Ice Age may be over in Kvarken, but the drama still continues to unfold.

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In castor oil extraction process, the bean coat is abrasive to the equipment and releases substances that modify the oil color, reducing its quality. A potential solution would be to run the extraction by compressing only the endosperm. Due to lack of information, the objective of this study was to evaluate the influence of forced air drying at 40, 60, 80 and 100 ºC and farmyard drying, in the mechanical properties of the beans, aiming to break the bean coat. Castor beans were subjected to compression tests, in two perpendicular directions, at a strain rate of 0.6 mm.s-1. Average values of force, deformation energy, strain, all at rupture, and stiffness were used to evaluate the effects of dehydration. It was observed that the heat treatments did not alter the mechanical properties of castor beans, the strain and stiffness values discriminate the differences between the directions and had the lowest coefficients of variation. It was concluded that forced air drying, more costly than farmyard drying, does not bring benefits to the decortication. However, regardless the heat treatment used, the mechanical stress lengthwise is the most suitable to promote decortication.

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ABSTRACT A portable flow board system was developed in the present study with the aim to facilitate lab-scale experiments of controlled atmosphere (CA) with fruits and vegetables. This sturdy flow board combines ease fabrication, low cost and gas economy. Its functionality is provided by manifolds and gas mixers. Each gaseous component is supplied by a gas cylinder through a differential valve of adjusted pressure control, generally at 6 kPa, and forced through 13 standardized restrictors coupled to each manifold output. Controlled atmospheres are then formed with one, two or three gases in 13 gas mixers affixed to the flow board base, which are further conducted through flexible tubes to storage mini-chambers that can also be used to study metabolic consumption and production of gaseous components. The restrictors used in the flow gaseous components were manufactured from microhematocrit test-type capillary glass tubes following the hot forming method under continuous air flow. The portable flow board showed to be low cost and simple post-harvest equipment that allows preparing controlled atmospheres in open systems with stable composition and flow, in a manner similar to traditional flow boards with control of gas escape by barostats.

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The general goal of the present work was to study whether spatial perceptual asymmetry initially observed in linguistic dichotic listening studies is related to the linguistic nature of the stimuli and/or is modality-specific, as well as to investigate whether the spatial perceptual/attentional asymmetry changes as a function of age and sensory deficit via praxis. Several dichotic listening studies with linguistic stimuli have shown that the inherent perceptual right ear advantage (REA), which presumably results from the left lateralized linguistic functions (bottom-up processes), can be modified with executive functions (top-down control). Executive functions mature slowly during childhood, are well developed in adulthood, and decline as a function of ageing. In Study I, the purpose was to investigate with a cross-sectional experiment from a lifespan perspective the age-related changes in top-down control of REA for linguistic stimuli in dichotic listening with a forced-attention paradigm (DL). In Study II, the aim was to determine whether the REA is linguistic-stimulus-specific or not, and whether the lifespan changes in perceptual asymmetry observed in dichotic listening would exist also in auditory spatial attention tasks that put load on attentional control. In Study III, using visual spatial attention tasks, mimicking the auditory tasks applied in Study II, it was investigated whether or not the stimulus-non-specific rightward spatial bias found in auditory modality is a multimodal phenomenon. Finally, as it has been suggested that the absence of visual input in blind participants leads to improved auditory spatial perceptual and cognitive skills, the aim in Study IV was to determine, whether blindness modifies the ear advantage in DL. Altogether 180-190 right-handed participants between 5 and 79 years of age were studied in Studies I to III, and in Study IV the performance of 14 blind individuals was compared with that of 129 normally sighted individuals. The results showed that only rightward spatial bias was observed in tasks with intensive attentional load, independent of the type of stimuli (linguistic vs. non-linguistic) or the modality (auditory vs. visual). This multimodal rightward spatial bias probably results from a complex interaction of asymmetrical perceptual, attentional, and/or motor mechanisms. Most importantly, the strength of the rightward spatial bias changed as a function of age and augmented praxis due to sensory deficit. The efficiency of the performance in spatial attention tasks and the ability to overcome the rightward spatial bias increased during childhood, was at its best in young adulthood, and decreased as a function of ageing. Between the ages of 5 and 11 years probably at first develops movement and impulse control, followed by the gradual development of abilities to inhibit distractions and disengage attention. The errors especially in bilateral stimulus conditions suggest that a mild phenomenon resembling extinction can be observed throughout the lifespan, but especially the ability to distribute attention to multiple targets simultaneously decreases in the course of ageing. Blindness enhances the processing of auditory bilateral linguistic stimuli, the ability to overcome a stimulus-driven laterality effect related to speech sound perception, and the ability to direct attention to an appropriate spatial location. It was concluded that the ability to voluntarily suppress and inhibit the multimodal rightward spatial bias changes as a function of age and praxis due to sensory deficit and probably reflects the developmental level of executive functions.

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The focus of the present work was on 10- to 12-year-old elementary school students’ conceptual learning outcomes in science in two specific inquiry-learning environments, laboratory and simulation. The main aim was to examine if it would be more beneficial to combine than contrast simulation and laboratory activities in science teaching. It was argued that the status quo where laboratories and simulations are seen as alternative or competing methods in science teaching is hardly an optimal solution to promote students’ learning and understanding in various science domains. It was hypothesized that it would make more sense and be more productive to combine laboratories and simulations. Several explanations and examples were provided to back up the hypothesis. In order to test whether learning with the combination of laboratory and simulation activities can result in better conceptual understanding in science than learning with laboratory or simulation activities alone, two experiments were conducted in the domain of electricity. In these experiments students constructed and studied electrical circuits in three different learning environments: laboratory (real circuits), simulation (virtual circuits), and simulation-laboratory combination (real and virtual circuits were used simultaneously). In order to measure and compare how these environments affected students’ conceptual understanding of circuits, a subject knowledge assessment questionnaire was administered before and after the experimentation. The results of the experiments were presented in four empirical studies. Three of the studies focused on learning outcomes between the conditions and one on learning processes. Study I analyzed learning outcomes from experiment I. The aim of the study was to investigate if it would be more beneficial to combine simulation and laboratory activities than to use them separately in teaching the concepts of simple electricity. Matched-trios were created based on the pre-test results of 66 elementary school students and divided randomly into a laboratory (real circuits), simulation (virtual circuits) and simulation-laboratory combination (real and virtual circuits simultaneously) conditions. In each condition students had 90 minutes to construct and study various circuits. The results showed that studying electrical circuits in the simulation–laboratory combination environment improved students’ conceptual understanding more than studying circuits in simulation and laboratory environments alone. Although there were no statistical differences between simulation and laboratory environments, the learning effect was more pronounced in the simulation condition where the students made clear progress during the intervention, whereas in the laboratory condition students’ conceptual understanding remained at an elementary level after the intervention. Study II analyzed learning outcomes from experiment II. The aim of the study was to investigate if and how learning outcomes in simulation and simulation-laboratory combination environments are mediated by implicit (only procedural guidance) and explicit (more structure and guidance for the discovery process) instruction in the context of simple DC circuits. Matched-quartets were created based on the pre-test results of 50 elementary school students and divided randomly into a simulation implicit (SI), simulation explicit (SE), combination implicit (CI) and combination explicit (CE) conditions. The results showed that when the students were working with the simulation alone, they were able to gain significantly greater amount of subject knowledge when they received metacognitive support (explicit instruction; SE) for the discovery process than when they received only procedural guidance (implicit instruction: SI). However, this additional scaffolding was not enough to reach the level of the students in the combination environment (CI and CE). A surprising finding in Study II was that instructional support had a different effect in the combination environment than in the simulation environment. In the combination environment explicit instruction (CE) did not seem to elicit much additional gain for students’ understanding of electric circuits compared to implicit instruction (CI). Instead, explicit instruction slowed down the inquiry process substantially in the combination environment. Study III analyzed from video data learning processes of those 50 students that participated in experiment II (cf. Study II above). The focus was on three specific learning processes: cognitive conflicts, self-explanations, and analogical encodings. The aim of the study was to find out possible explanations for the success of the combination condition in Experiments I and II. The video data provided clear evidence about the benefits of studying with the real and virtual circuits simultaneously (the combination conditions). Mostly the representations complemented each other, that is, one representation helped students to interpret and understand the outcomes they received from the other representation. However, there were also instances in which analogical encoding took place, that is, situations in which the slightly discrepant results between the representations ‘forced’ students to focus on those features that could be generalised across the two representations. No statistical differences were found in the amount of experienced cognitive conflicts and self-explanations between simulation and combination conditions, though in self-explanations there was a nascent trend in favour of the combination. There was also a clear tendency suggesting that explicit guidance increased the amount of self-explanations. Overall, the amount of cognitive conflicts and self-explanations was very low. The aim of the Study IV was twofold: the main aim was to provide an aggregated overview of the learning outcomes of experiments I and II; the secondary aim was to explore the relationship between the learning environments and students’ prior domain knowledge (low and high) in the experiments. Aggregated results of experiments I & II showed that on average, 91% of the students in the combination environment scored above the average of the laboratory environment, and 76% of them scored also above the average of the simulation environment. Seventy percent of the students in the simulation environment scored above the average of the laboratory environment. The results further showed that overall students seemed to benefit from combining simulations and laboratories regardless of their level of prior knowledge, that is, students with either low or high prior knowledge who studied circuits in the combination environment outperformed their counterparts who studied in the laboratory or simulation environment alone. The effect seemed to be slightly bigger among the students with low prior knowledge. However, more detailed inspection of the results showed that there were considerable differences between the experiments regarding how students with low and high prior knowledge benefitted from the combination: in Experiment I, especially students with low prior knowledge benefitted from the combination as compared to those students that used only the simulation, whereas in Experiment II, only students with high prior knowledge seemed to benefit from the combination relative to the simulation group. Regarding the differences between simulation and laboratory groups, the benefits of using a simulation seemed to be slightly higher among students with high prior knowledge. The results of the four empirical studies support the hypothesis concerning the benefits of using simulation along with laboratory activities to promote students’ conceptual understanding of electricity. It can be concluded that when teaching students about electricity, the students can gain better understanding when they have an opportunity to use the simulation and the real circuits in parallel than if they have only the real circuits or only a computer simulation available, even when the use of the simulation is supported with the explicit instruction. The outcomes of the empirical studies can be considered as the first unambiguous evidence on the (additional) benefits of combining laboratory and simulation activities in science education as compared to learning with laboratories and simulations alone.

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Human trafficking is not a new phenomenon. It has existed in various forms for ages around the world. Some researchers have even compared it to slavery, calling it the modern form of slavery in the 21st century. This study is particularly interested in the role of work-related human trafficking in Finnish business. In order for something to be called work-related human trafficking, the concepts of forced labour and human trafficking have to overlap. From the economic point of view, human trafficking is governed by the laws of supply and demand. In many countries the global pressure on cutting costs has created two trends: the increased supply of migrant workers and the deregulation of labour markets. These competitive pressures can have an adverse impact on the conditions of employment and, in the worst cases, can lead to forced labour and trafficking. In fact, trafficking has become one of the most profitable illicit industries worldwide, generating tremendous profits due to its low costs and huge profits. Therefore, it is important to investigate the phenomenon from the business point of view. This study is a qualitative research conducted by using theme interviews as a research approach. Altogether 13 interviews have been conducted and some secondary data has been used in order to find out what the role of human trafficking is in Finnish business. The special sectors investigated are the Finnish construction and service sectors. The theory framework used in this study follows the stakeholder approach. The relevant stakeholder groups for this study are: ‘institutions and authorities’, ‘law enforcement’, ‘management’ and ‘employees – potential victims’ of trafficking. With the help of these stakeholder groups, a holistic picture of the phenomenon is formed. It can be concluded that the role of human trafficking is complicated but it does exist in Finnish business. It appears in low-cost business sectors where the demand for cheap labour is high. Thus, often the victims are foreigners who do not know the culture or the Finnish conditions of employment. Especially smaller Finnish companies are at risk of getting involved in human trafficking or related exploitation cases since monitoring is much more scarce in these firms than in larger companies. The risk of human trafficking and exploitation is also higher at the bottom of the complicated subcontracting chains or when using foreign recruitment agencies. Thus, the study believes that active and intensive collaboration between the company’s different stakeholder groups is needed in order to prevent work-related human trafficking from flourishing in Finland.

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Cell division (mitosis) is a fundamental process in the life cycle of a cell. Equal distribution of chromosomes between the daughter cells is essential for the viability and well-being of an organism: loss of fidelity of cell division is a contributing factor in human cancer and also gives rise to miscarriages and genetic birth defects. For maintaining the proper chromosome number, a cell must carefully monitor cell division in order to detect and correct mistakes before they are translated into chromosomal imbalance. For this purpose an evolutionarily conserved mechanism termed the spindle assembly checkpoint (SAC) has evolved. The SAC comprises a complex network of proteins that relay and amplify mitosis-regulating signals created by assemblages called kinetochores (KTs). Importantly, minor defects in SAC signaling can cause loss or gain of individual chromosomes (aneuploidy) which promotes tumorigenesis while complete failure of SAC results in cell death. The latter event has raised interest in discovery of low molecular weight (LMW) compounds targeting the SAC that could be developed into new anti-cancer therapeutics. In this study, we performed a cell-based, phenotypic high-throughput screen (HTS) to identify novel LMW compounds that inhibit SAC function and result in loss of cancer cell viability. Altogether, we screened 65 000 compounds and identified eight that forced the cells prematurely out of mitosis. The flavonoids fisetin and eupatorin, as well as the synthetic compounds termed SACi2 and SACi4, were characterized in more detail utilizing versatile cell-based and biochemical assays. To identify the molecular targets of these SAC-suppressing compounds, we investigated the conditions in which SAC activity became abrogated. Eupatorin, SACi2 and SACi4 preferentially abolished the tensionsensitive arm of the SAC, whereas fisetin lowered also the SAC activity evoked by lack of attachments between microtubules (MTs) and KTs. Consistent with the abrogation of SAC in response to low tension, our data indicate that all four compounds inhibited the activity of Aurora B kinase. This essential mitotic protein is required for correction of erratic MT-KT attachments, normal SAC signaling and execution of cytokinesis. Furthermore, eupatorin, SACi2 and SACi4 also inhibited Aurora A kinase that controls the centrosome maturation and separation and formation of the mitotic spindle apparatus. In line with the established profound mitotic roles of Aurora kinases, these small compounds perturbed SAC function, caused spindle abnormalities, such as multi- and monopolarity and fragmentation of centrosomes, and resulted in polyploidy due to defects in cytokinesis. Moreover, the compounds dramatically reduced viability of cancer cells. Taken together, using a cell-based HTS we were able to identify new LMW compounds targeting the SAC. We demonstrated for the first time a novel function for flavonoids as cellular inhibitors of Aurora kinases. Collectively, our data support the concept that loss of mitotic fidelity due to a non-functional SAC can reduce the viability of cancer cells, a phenomenon that may possess therapeutic value and fuel development of new anti-cancer drugs.

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Tutkielma kuvaa Suomen arpajaislain muutosprosessia ja sen taustalla olevia tekijöitä sekä muutoksen vaikutuksia rahapelien markkinointiin. Tutkielmassa tarkastellaan erityisesti vuoden 2010 arpajaislain uudistusta ja vaikutuksia. Rahapelejä on kohdeltu Europpan Yhteisöjen lainsäädännössä eri tavalla verrattuna muuhun liiketoimintaan eikä siihen ole sovellettu palveluiden vapaan liikkuvuuden periaatetta samassa mittakaavassa kuin muuhun kaupalliseen toimintaan. Rahapelipalveluiden tarjoaminen internetissä on asettanut valtioiden vanhat rahapelimonopolit uusien haasteiden eteen myös lainsäädännöllisesti. Suomessa valtio on lainmuutoksilla pyrkinyt turvaamaan vallitsevan tilanteen, jossa rahapelipalveluiden tarjoamisesta suomalaisille vastaavat tietyt yhtiöt ja yhdistykset yksinoikeudella. Tutkielma pyrkii kuvaamaan tätä prosessia käyden läpi sen syitä ja seurauksia. Erityishuomion kohteeksi on otettu lakimuutosten vaikutukset ulkomaisten rahapeliyhtiöiden mainontaan suomalaisessa mediassa. Lähteinä on käytetty pääasiassa viranomaislähteitä, mutta tutkielmassa on pyritty tuomaan esille myös rahapelialan toimijoiden näkökulmia.

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Companies today are forced to innovate in order to remain within business. Such innovation projects undertaken by the companies are defined in this study as creative ideas which have been managed through “Stage-Gate” innovation process. This process is used to manage innovation projects as they proceed from being newly created to ready for launching/implementing. This has ensured that the companies manage the innovation project right. However, with so many new creative ideas the companies can come up within limited resources, the companies must rely on Innovation Project Portfolio Management (IPPM) to ensure that they are managing only the right innovation projects. Although, there are many tools and techniques available for use within Project Portfolio Management, there is still no consensus on which are the most effective and no standard framework has been established especially for IPPM. Thus, this study proposes a practical framework for which individual innovative organization can follow as a guideline to manage its innovation project portfolio. The study theoretically first addresses the key differences between project portfolio management of innovation projects and other traditional projects - one of which is the stage nature of innovation projects due to their unclear objectives from the beginning compare to clearly established objectives of traditional projects. Secondly, different tools and techniques which can be used are examined based on the three goals of IPPM: (1) Maximizing the Value of Innovation Project Portfolio: Financial Methods, Decision Trees, Scoring Models and Checklists; (2) Balancing Innovation Project Portfolio: Visual Representations; and (3) Aligning Innovation Project Portfolio with Strategy: Bottom-Up (Scoring Models with Strategic Criteria) and Top-Down (Strategic Buckets). Finally, the two approaches in which IPPM can be integrated with Stage-Gate innovation process are discussed: (1) Gates- Dominated; and (2) Portfolio Reviews-Dominated. Practically, this study investigates IPPM of a case organization, and through analysis of the case study results proposes a practical framework for case organization to improve its current management of innovation project portfolio. This framework is then generalized to propose a final practical framework or guideline for which an innovative organization can follow to manage its innovation project portfolio.

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The objective of this review on the investigation of "cara inchada" in cattle (CI), pursued over the last 30 years, was to elucidate the pathogenicity of the disease and come to proper conclusions on its etiology. CI has been widely considered to be of nutritional origin, caused primarily by mineral deficiency or imbalance. However, the disease consists of a rapidly progressive periodontitis, affecting the periodontal tissues at the level of the premolars and molars during the period of tooth eruption generally starting in young calves. The disease led to great economic losses for farmers in central-western Brazil, after the occupation of new land for cattle raising in the 1960s and 1970s. The lateral enlargement of the maxillary bones of affected calves gave the disease the popular name of "cara inchada", i.e., swollen or enlarged face. The enlargement was found to be due to a chronic ossifying periostitis resulting from the purulent alveolitis of CI. Black-pigmented non-saccharolytic Bacteroides melaninogenicus, always together with Actinomyces (Corynebacterium) pyogenes, were isolated in large numbers from the periodontal lesions. B. melaninogenicus could be isolated in small numbers also from the marginal gingiva of a few healthy calves maintained on CI-free farms. "In vitro"-assays showed that streptomycin and actinomycin, as well as the supernatants of cultivates of actinomycetes from soils of CI-prone farms, applied in subinhibitory concentrations to the bacteria tested, enhanced significantly (up to 10 times) the adherence of the black-pigmented B.melaninogenicus to epithelial cells of the bovine gingiva. The antibiotics are apparently produced in large quantities by the increased number of soil actinomycetes, including the genus Streptomyces, that develop when soil microflora are modified by cultivating virgin forest or "Cerrado" (tree-savanna) for the first time for cattle grazing. The epidemiology of CI now provides strong evidence that the ingestion with the forage of such antibiotics could possibly be an important determinant factor for the onset and development of this infectious periodontitis. The antibiotic enhanced adherence of B.melaninogenicus to the sulcus-epithelium of the marginal gingiva, is thought to allow it to colonize, form a plaque and become pathogenic. There is experimental evidence that this determinant factor for the development of the periodontitis is present also in the milk of the mothers of CI-diseased calves. It has been shown that the bacteria isolated from the periodontal CI-lesions produce enzymes and endotoxins capable of destroying the periodontal tissues. The epidemiology of CI, with its decline in incidence and its disappearance after several years, could be explained by the fact that the former equilibrium of the microflora of the once undisturbed virgin soil has been reached again and that the number of antibiotic producing actinomycetes has been anew reduced. By this reasoning and all the data available, CI should be considered as a multifactorial infectious disease, caused primarily by the anaerobic black-pigmented non-saccharolytic Bacteroides melaninogenicus, always together with the micro-anaerobic Actinomyces pyogenes. Accordingly, the onset and development of the infectious periodontitis is apparently determined by ingestion with the forage of subinhibitory concentrations of antibiotics produced in recently cultivated virgin soils. This hypothesis is supported by the recent observation of renewed outbreaks of CI-periodontitis in former CI-prone areas, following fresh cultivation after many years. The infectious nature of CI is confirmed by trials in which virginiamycin was used efficiently for the oral treatment of CI-diseased cattle. Previously it has been shown, that spiramycin and virginiamycin, used as additives in mineral supplements, prevented CI-periodontitis.