43 resultados para Specification searching

em Helda - Digital Repository of University of Helsinki


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Objectives. In this research I analyzed the learning process of teacher students in a planning meeting using the expansive learning cycle and types of interaction approaches. In activity theory framework the expansive learning cycle has been applied widely in analyzing learning processes taking several years. However, few studies exist utilizing expansive cycles in analyzing short single meetings. In the activity theory framework talk and interaction have been analyzed using following types of interaction: coordination, cooperation and communication. In these studies single interaction situations have been analyzed, in which the status and power positions of participants has been very different. Interactions of self-directed teams, in which the participants are equal, have been examined very little. I am not aware of any studies, in which both learning actions of the expansive cycle and types of interaction by analyzing the same data would have been utilized. The aim of my study was to describe the process of collaborative innovative learning in a situation where the student group tries to accomplish a broad and ill-defined learning task. I aim to describe, how this planning process proceeds through different phases of learning actions of the expansive cycle. My goal is to understand and describe the transformations in the quality of interaction and transitions which are related to it. Another goal of this study is to specify the possible similarities and differences between expansive learning and types of interactions. Methods. Data of this study consisted of videotaped meetings, which were part of the study module for class teacher degree. The first meeting of the study module was chosen to be the primary research material. Five students were present in the group meeting. Transcription of the conversation was analyzed by classifying the turns of conversation following phases of the expansive cycle. After that the material was categorized again by using types of interaction. Results and conclusions. As a result of this study I was able to trace all the phases of the expansive cycle except one. Also, I was able to identify all interaction types. When I compared the two modes of analysis side by side I was able to find connecting main phases. Thus I was able to identify the interdependence between the two ways of analysis on a higher level, although I was not able to notice correlation on the level of individual phases. Based on this, I conclude that learning of the group was simultaneously specification and formulation of the object at the different phases of expansive learning and transformation of the quality of the interaction while searching for the common object.

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In a search for new phenomena in a signature suppressed in the standard model of elementary particles (SM), we compare the inclusive production of events containing a lepton, a photon, significant transverse momentum imbalance (MET), and a jet identified as containing a b-quark, to SM predictions. The search uses data produced in proton-antiproton collisions at 1.96 TeV corresponding to 1.9 fb-1 of integrated luminosity taken with the CDF detector at the Fermilab Tevatron. We find 28 lepton+photon+MET+b events versus an expectation of 31.0+4.1/-3.5 events. If we further require events to contain at least three jets and large total transverse energy, simulations predict that the largest SM source is top-quark pair production with an additional radiated photon, ttbar+photon. In the data we observe 16 ttbar+photon candidate events versus an expectation from SM sources of 11.2+2.3/-2.1. Assuming the difference between the observed number and the predicted non-top-quark total is due to SM top quark production, we estimate the ttg cross section to be 0.15 +- 0.08 pb.

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Poor pharmacokinetics is one of the reasons for the withdrawal of drug candidates from clinical trials. There is an urgent need for investigating in vitro ADME (absorption, distribution, metabolism and excretion) properties and recognising unsuitable drug candidates as early as possible in the drug development process. Current throughput of in vitro ADME profiling is insufficient because effective new synthesis techniques, such as drug design in silico and combinatorial synthesis, have vastly increased the number of drug candidates. Assay technologies for larger sets of compounds than are currently feasible are critically needed. The first part of this work focused on the evaluation of cocktail strategy in studies of drug permeability and metabolic stability. N-in-one liquid chromatography-tandem mass spectrometry (LC/MS/MS) methods were developed and validated for the multiple component analysis of samples in cocktail experiments. Together, cocktail dosing and LC/MS/MS were found to form an effective tool for increasing throughput. First, cocktail dosing, i.e. the use of a mixture of many test compounds, was applied in permeability experiments with Caco-2 cell culture, which is a widely used in vitro model for small intestinal absorption. A cocktail of 7-10 reference compounds was successfully evaluated for standardization and routine testing of the performance of Caco-2 cell cultures. Secondly, cocktail strategy was used in metabolic stability studies of drugs with UGT isoenzymes, which are one of the most important phase II drug metabolizing enzymes. The study confirmed that the determination of intrinsic clearance (Clint) as a cocktail of seven substrates is possible. The LC/MS/MS methods that were developed were fast and reliable for the quantitative analysis of a heterogenous set of drugs from Caco-2 permeability experiments and the set of glucuronides from in vitro stability experiments. The performance of a new ionization technique, atmospheric pressure photoionization (APPI), was evaluated through comparison with electrospray ionization (ESI), where both techniques were used for the analysis of Caco-2 samples. Like ESI, also APPI proved to be a reliable technique for the analysis of Caco-2 samples and even more flexible than ESI because of the wider dynamic linear range. The second part of the experimental study focused on metabolite profiling. Different mass spectrometric instruments and commercially available software tools were investigated for profiling metabolites in urine and hepatocyte samples. All the instruments tested (triple quadrupole, quadrupole time-of-flight, ion trap) exhibited some good and some bad features in searching for and identifying of expected and non-expected metabolites. Although, current profiling software is helpful, it is still insufficient. Thus a time-consuming largely manual approach is still required for metabolite profiling from complex biological matrices.

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The study examines the debate in Finland at the beginning of the 20th century surrounding the philosophy of Henri Bergson. Both within as well as outside of academic philosophy Bergsonism was adapted to the philosophical and cultural landscape in Finland by a process of selective appropriation. The ambiguous relationship between the sender and the receiver is accentuated in reference to philosophical celebrities such as Bergson, whose reputations spread more quickly than the content of their philosophy and whose names are drawn into the political and social discourse. As a philosophical movement the aim of Bergsonism was to create a scientific philosophy of life as an alternative to both idealism and modern empirical and antimetaphysical currents, during a period when European philosophy was searching for new guidelines after the collapse of the idealistic system philosophies of the 19th century. This reorientation is examined from a Finnish viewpoint and in the light of the process of intellectual importation. The study examines how elements from an international discourse were appropriated within the philosophical field in Finland against a background of changes in the role of the university and the educated elites as well as the position of philosophy within the disciplinary hierarchy. Philosophical reception was guided by expectations that had arisen in a national context, for example when Bergsonism in Finland was adjusted to a moral and educational ideal of self-cultivation, and often served as a means for philosophers to internationalize their own views in order to strengthen their position on the national stage. The study begins with some introductory remarks on the international circulation of ideas from the point of view of the periphery. The second section presents an overview of the shaping of the philosophical field at the turn of the 20th century, the naturalism and positivism of the late 19th century that were the objects of Bergson s critique, and an introduction to the attempts of a philosophy of life to make its way between idealism and naturalism. The third and main section of the study begins with a brief presentation of the main features of the philosophy of Bergson, followed by a closer examination of the different comments and analyses that it gave rise to in Finland. The final section addresses the ideological implications of Bergsonism within the framework of a political annexation of the philosophy of life at the beginning of the 20th century.

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The study is a philosophical analysis of Israel Scheffler’s philosophy of education, focusing on three crucial conceptions in his philosophy: the conception of rationality, the conception of human nature, and the conception of reality. The interrelations of these three concepts as well as their relations to educational theorizing are analysed and elaborated. A conceptual problem concerning Scheffler’s ideal of rationality derives from Scheffler’s supposition of the strong analogy between science education and moral education in terms of the ideal of rationality. This analogy is argued to be conceptually problematic, since the interconnections of rationality, objectivity, and truth, appear to differ from each other in the realms of ethics and science, given the presuppositions of ontological realism and ethical naturalism, to which Scheffler explicitly subscribes. This study considers two philosophical alternatives for solving this problem. The first alternative relates the analogy to the normative concept of personhood deriving from the teleological understanding of human nature. Nevertheless, this position turns out to be problematic for Scheffler, since he rejects all teleological thinking in his philosophy. The problem can be solved, as it is argued, by limiting Scheffler’s rejection of teleology – in light of his philosophical outlook on the whole – in a manner that allows a modest version of a teleological conception of human nature. The second alternative, based especially on Scheffler’s later contributions, is to suggest that reality is actually more complex and manifold than it appears to be in light of a contemporary naturalist worldview. This idea of plurealism – Scheffler’s synthesis of pluralism and realism – is represented especially in Scheffler’s contributions related to his debate with Nelson Goodman dealing with both constructivism and realism. The idea of plurealism is not only related to the ethics-science-distinction, but is more widely related to the relationship between ontological realism and the incommensurable systems of description in diverse realms of human understanding. The Scheffler-Goodman debate is also analysed in relation to the contemporary constructivism-realism debate in educational philosophy. In terms of educational questions, Scheffler’s plurealism is argued as offering a fruitful perspective. Scheffler’s philosophy of education can be interpreted as searching for solutions to the problems deriving from the tension between the tradition of analytical philosophy and the complexity and multiplicity of educational reality. The complexity of reality combined with the supposition of the limitedness of human knowledge does not lead Scheffler to relativism or particularism, but, in contrast, Schefflerian formulations of rationality and objectivity preserve the possibility for critical inquiry in all realms of educational reality. In light of this study, Scheffler’s philosophy of education provides an exceptional example of combining ontological realism, epistemological fallibilism, and the defence of the ideal of rationality, combined with a wide-ranging understanding of educational reality.

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Today information and communication technology allows us to use multimedia more than ever before in e-learning materials. Multimedia though can increase cognitive load in learning process. Because of that it cannot be taken granted what kind of learning materials should be produced. This paper intended to study the diversity of e-learning materials and the factors related cognitive load. The main purpose was to study the multimodality of the multimedia learning materials. The subject of this study is the learning materials on the web site Kansalaisen ABC published by YLE. Learning materials in the web site were approached from three different perspectives. The specific questions were: (1) What kind of form features are used in the representations of the learning material? Are certain form features preferred over others? (2) How do the cognitive load factors take shape in learning materials and between the forms? (3) How does the multimodality phenomenon appear in the learning materials and in what ways are form features and cognitive load factors related to multimodality? In this case study a qualitative approach was used. Analysis of the form features and the cognitive load factors in learning materials were based on content analysis. Form features included the specification of a format, the structure, the interactivity type and the type of learning material. The results showed that the web sites include various representations of both verbal and visual forms. Cognitive load factors were related mostly to visual than verbal material. Material presented according to the principles of cognitive multimedia theory multimedia representations did not cause cognitive overload in the informants. Cognitive load was increased in the case of students needing to split their attention between the multimedia forms in time and place. The results indicated how different individual characteristics are reflected by the cognitive load factors.

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The aim of the study was to analyze and facilitate collaborative design in a virtual learning environment (VLE). Discussions of virtual design in design education have typically focused on technological or communication issues, not on pedagogical issues. Yet in order to facilitate collaborative design, it is also necessary to address the pedagogical issues related to the virtual design process. In this study, the progressive inquiry model of collaborative designing was used to give a structural level of facilitation to students working in the VLE. According to this model, all aspects of inquiry, such as creating the design context, constructing a design idea, evaluating the idea, and searching for new information, can be shared in a design community. The study consists of three design projects: 1) designing clothes for premature babies, 2) designing conference bags for an international conference, and 3) designing tactile books for visually impaired children. These design projects constituted a continuum of design experiments, each of which highlighted certain perspectives on collaborative designing. The design experiments were organized so that the participants worked in design teams, both face-to-face and virtually. The first design experiment focused on peer collaboration among textile teacher students in the VLE. The second design experiment took into consideration end-users needs by using a participatory design approach. The third design experiment intensified computer-supported collaboration between students and domain experts. The virtual learning environments, in these design experiments, were designed to support knowledge-building pedagogy and progressive inquiry learning. These environments enabled a detailed recording of all computer-mediated interactions and data related to virtual designing. The data analysis was based on qualitative content analysis of design statements in the VLE. This study indicated four crucial issues concerning collaborative design in the VLE in craft and design education. Firstly, using the collaborative design process in craft and design education gives rise to special challenges of building learning communities, creating appropriate design tasks for them, and providing tools for collaborative activities. Secondly, the progressive inquiry model of collaborative designing can be used as a scaffold support for design thinking and for reflection on the design process. Thirdly, participation and distributed expertise can be facilitated by considering the key stakeholders who are related to the design task or design context, and getting them to participate in virtual designing. Fourthly, in the collaborative design process, it is important that team members create and improve visual and technical ideas together, not just agree or disagree about proposed ideas. Therefore, viewing the VLE as a medium for collaborative construction of the design objects appears crucial in order to understand and facilitate the complex processes in collaborative designing.

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Tutkimuksessa etsittiin vastauksia kysymyksiin, mistä yksilöllisyys muodostuu ja miten se ilmenee musliminaisten pukeutumisessa. Vastauksia tutkimuskysymyksiin haettiin teorian ja aineiston vuoropuheluun perustuvalla fenomenologisesti orientoituneella sisällönanalyysilla. Analysoitava aineisto on hankittu haastattelemalla yhdeksää Suomessa asuvaa musliminaista. Tutkimuksessa yksilöllisyyttä pukeutumisessa on tarkasteltu prosessina. Prosessiin vaikuttavina tekijöinä on tarkasteltu yksilön olemusta, personallisuutta, minuutta, identiteettejä, uskontoa, kulttuuria ja sosiaalisia suhteita. Prosessissa keskeistä aineiston perusteella oli positiivisen minuuden kokemuksen tavoittelu, joka tarkoitti naisille intuitiivista oman itsensä tunnistamista ja tyytyväisyyttä peilin heijastamaan kuvaan. Yksilöllisen pukeutumisen voikin sanoa olevan seurausta positiivisen minuuden kokemuksen tavoittelusta, koska jokaiselle naiselle erilainen pukeutuminen antoi tunteen sopivuudesta itselle. Esimerkiksi uskonnolliselle musliminaisille pään peittäminen merkitsee oman minuuden toteutumista, koska hän kokee tuon pukeutumisen olevan uskon mukainen pukeutumistapa. Toiselle musliminaiselle pään peittäminen voi merkitä positiivisen minuuden kokemuksen menettämistä. Yksilöllisyys pukeutumisessa ilmeni monin tavoin. Osa naisista peittää julkisuudessa koko päänsä ja vartalonsa, osa ei peitä päätään ja jotkut pukeutuvat jopa tiukkoihin tai paljastaviin vaatteisiin. Suomessa on myös kasvonsa peittäviä musliminaisia, joita ei kuitenkaan ole mukana tässä tutkimuksessa. Yksilöllisyyttä ilmeni kuitenkin myös samalla tavalla pukeutuvien musliminaisten ryhmässä. Yksilöllisyys pukeutumisessa ilmeni erilaisina vaatekappaleina, hiustyyleinä, valintoina, yksityiskohtina ja väreinä. Yksilöllisyydessä ei kuitenkaan ole kyse vain havaittavasta pukeutumisen erilaisuudesta, vaan siitä, miten kukin musliminainen kuuluu tähän maailmaan ja toteuttaa omaa minuuttaan pukeutumisella. Tämä tarkoittaa sitä, että tutkimuksessa yksilöllisenä pukeutumisena voidaan pitää sitäkin, mikä monen suomalaisen mielestä ei näytä yksilölliseltä. Avainsanat: Yksilöllisyys, minuus, pukeutuminen, islam, naiset, prosessi, kokemus

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Critical cellular decisions such as should the cell proliferate, migrate or differentiate, are regulated by stimulatory signals from the extracellular environment, like growth factors. These signals are transformed to cellular responses through their binding to specific receptors present at the surface of the recipient cell. The epidermal growth factor receptor (EGF-R/ErbB) pathway plays key roles in governing these signals to intracellular events and cell-to-cell communication. The EGF-R forms a signaling network that participates in the specification of cell fate and coordinates cell proliferation. Ligand binding triggers receptor dimerization leading to the recruitment of kinases and adaptor proteins. This step simultaneously initiates multiple signal transduction pathways, which result in activation of transcription factors and other target proteins, leading to cellular alterations. It is known that mutations of EGF-R or in the components of these pathways, such as Ras and Raf, are commonly involved in human cancer. The four best characterized signaling pathways induced by EGF-R are the mitogen-activated protein kinase cascades (MAPKs), the lipid kinase phosphatidylinositol 3 kinase (PI3K), a group of transcription factors called Signal Transducers and Activator of Transcription (STAT), and the phospholipase Cγ; (PLCγ) pathways. The activation of each cascade culminates in kinase translocation to the nucleus to stimulate various transcription factors including activator protein 1 (AP-1). AP-1 family proteins are basic leucine zipper (bZIP) transcription factors that are implicated in the regulation of a variety of cellular processes (proliferation and survival, growth, differentiation, apoptosis, cell migration, transformation). Therefore, the regulation of AP-1 activity is critical for the decision of cell fate and their deregulated expression is widely associated with many types of cancers, such as breast and prostate cancers. The aims of this study were to characterize the roles of EGF-R signaling during normal development and malignant growth in vitro and in vivo using different cell lines and tissue samples. We show here that EGF-R regulates cell proliferation but is also required for regulation of AP-1 target gene expression in fibroblasts in a MAP-kinase mediated manner. Furthermore, EGF-R signaling is essential for enterocyte proliferation and migration during intestinal maturation. EGF-R signaling network, especially PI3-K-Akt pathway mediated AP-1 activity is involved in cellular survival in response to ionizing radiation. Taken together, these results elucidate the connection of EGF-R and AP-1 in various cellular contexts and show their importance in the regulation of cellular behaviour presenting new treatment cues for intestinal perforations and cancer therapy.

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This dissertation examines the short- and long-run impacts of timber prices and other factors affecting NIPF owners' timber harvesting and timber stocking decisions. The utility-based Faustmann model provides testable hypotheses of the exogenous variables retained in the timber supply analysis. The timber stock function, derived from a two-period biomass harvesting model, is estimated using a two-step GMM estimator based on balanced panel data from 1983 to 1991. Timber supply functions are estimated using a Tobit model adjusted for heteroscedasticity and nonnormality of errors based on panel data from 1994 to 1998. Results show that if specification analysis of the Tobit model is ignored, inconsistency and biasedness can have a marked effect on parameter estimates. The empirical results show that owner's age is the single most important factor determining timber stock; timber price is the single most important factor in harvesting decision. The results of the timber supply estimations can be interpreted using utility-based Faustmann model of a forest owner who values a growing timber in situ.

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Strawberries (Fragaria sp.) are adapted to diverse environmental conditions from the tropics to about 70ºN, so different responses to environmental conditions can be found. Most genotypes of garden strawberry (F. x ananassa Duch.) and woodland strawberry (F. vesca L.) are short-day (SD) plants that are induced to flowering by photoperiods under a critical limit, but also various photoperiod x temperature interactions can be found. In addition, continuously flowering everbearing (EB) genotypes are found. In addition to flowering, axillary bud differentiation in strawberry is regulated by photoperiod. In SD conditions, axillary buds differentiate to rosette-like structures called "branch crowns", whereas in long-day conditions (LD) they form runners, branches with 2 long internodes followed by a daughter plant (leaf rosette). The number of crown branches determines the yield of the plant, since inflorescences are formed from the apical meristems of the crown. Although axillary bud differentiation is an important developmental process in strawberries, its environmental and hormonal regulation has not been characterized in detail. Moreover, the genetic mechanisms underlying axillary bud differentiation and regulation of flowering time in these species are almost completely unresolved. These topics have been studied in this thesis in order to enhance strawberry research, cultivation and breeding. The results showed that 8-12 SD cycles suppressed runner initiation from the axillary buds of the garden strawberry cv. Korona with the concomitant induction of crown branching, and 3 weeks of SD was sufficient for the induction of flowering in the main crown. Furthermore, a second SD treatment given a few weeks after the first SD period can be used to induce flowering in the primary branch crowns and to induce the formation of secondary branches. Thus, artificial SD treatments effectively stimulate crown branching, providing one means for the increase of cropping (yield) potential in strawberry. It was also shown by growth regulation applications, quantitave hormone analysis and gene expression analysis that gibberellin (GA) is one of the key signals involved in the photoperiod control of shoot differentiation. The results indicate that photoperiod controls GA activity specifically in axillary buds, thereby determining bud fate. It was further shown that chemical control of GA biosynthesis by prohexadione-calcium can be utilized to prevent excessive runner formation and induce crown branching in strawberry fields. Moreover, ProCa increased berry yield up to 50%, showing that it is an easier and more applicable alternative to artificial SD treatments for controlling strawberry crown development and yield. Finally, flowering gene pathways in Fragaria were explored by searching for homologs of 118 Arabidopsis thaliana flowering-time genes. In total, 66 gene homologs were identified, and they distributed to all known flowering pathways, suggesting the presence of these pathways also in strawberry. Expression analysis of selected genes revealed that the mRNA of putative floral identity gene APETALA1 accumulated in the shoot apex of the EB genotype after the induction of flowering, whereas it was absent in vegetative SD genotype, indicating the usefulness of this gene product as the marker of floral initiation. The present data enables the further exploration of strawberry flowering pathways with genetic transformation, gene mapping and transcriptomics methods.

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ALICE (A Large Ion Collider Experiment) is an experiment at CERN (European Organization for Nuclear Research), where a heavy-ion detector is dedicated to exploit the unique physics potential of nucleus-nucleus interactions at LHC (Large Hadron Collider) energies. In a part of that project, 716 so-called type V4 modules were assembles in Detector Laboratory of Helsinki Institute of Physics during the years 2004 - 2006. Altogether over a million detector strips has made this project the most massive particle detector project in the science history of Finland. One ALICE SSD module consists of a double-sided silicon sensor, two hybrids containing 12 HAL25 front end readout chips and some passive components, such has resistors and capacitors. The components are connected together by TAB (Tape Automated Bonding) microcables. The components of the modules were tested in every assembly phase with comparable electrical tests to ensure the reliable functioning of the detectors and to plot the possible problems. The components were accepted or rejected by the limits confirmed by ALICE collaboration. This study is concentrating on the test results of framed chips, hybrids and modules. The total yield of the framed chips is 90.8%, hybrids 96.1% and modules 86.2%. The individual test results have been investigated in the light of the known error sources that appeared during the project. After solving the problems appearing during the learning-curve of the project, the material problems, such as defected chip cables and sensors, seemed to induce the most of the assembly rejections. The problems were typically seen in tests as too many individual channel failures. Instead, the bonding failures rarely caused the rejections of any component. One sensor type among three different sensor manufacturers has proven to have lower quality than the others. The sensors of this manufacturer are very noisy and their depletion voltage are usually outside of the specification given to the manufacturers. Reaching 95% assembling yield during the module production demonstrates that the assembly process has been highly successful.