925 resultados para Model basic science research


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The marine environment is certainly one of the most complex systems to study, not only because of the challenges posed by the nature of the waters, but especially due to the interactions of physical, chemical and biological processes that control the cycles of the elements. Together with analytical chemists, oceanographers have been making a great effort in the advancement of knowledge of the distribution patterns of trace elements and processes that determine their biogeochemical cycles and influences on the climate of the planet. The international academic community is now in prime position to perform the first study on a global scale for observation of trace elements and their isotopes in the marine environment (GEOTRACES) and to evaluate the effects of major global changes associated with the influences of megacities distributed around the globe. This action can only be performed due to the development of highly sensitive detection methods and the use of clean sampling and handling techniques, together with a joint international program working toward the clear objective of expanding the frontiers of the biogeochemistry of the oceans and related topics, including climate change issues and ocean acidification associated with alterations in the carbon cycle. It is expected that the oceanographic data produced this coming decade will allow a better understanding of biogeochemical cycles, and especially the assessment of changes in trace elements and contaminants in the oceans due to anthropogenic influences, as well as its effects on ecosystems and climate. Computational models are to be constructed to simulate the conditions and processes of the modern oceans and to allow predictions. The environmental changes arising from human activity since the 18th century (also called the Anthropocene) have made the Earth System even more complex. Anthropogenic activities have altered both terrestrial and marine ecosystems, and the legacy of these impacts in the oceans include: a) pollution of the marine environment by solid waste, including plastics; b) pollution by chemical and medical (including those for veterinary use) substances such as hormones, antibiotics, legal and illegal drugs, leading to possible endocrine disruption of marine organisms; and c) ocean acidification, the collateral effect of anthropogenic emissions of CO2 into the atmosphere, irreversible in the human life time scale. Unfortunately, the anthropogenic alteration of the hydrosphere due to inputs of plastics, metal, hydrocarbons, contaminants of emerging concern and even with formerly "exotic" trace elements, such us rare earth elements is likely to accelerate in the near future. These emerging contaminants would likely soon present difficulties for studies in pristine environments. All this knowledge brings with it a great responsibility: helping to envisage viable adaptation and mitigation solutions to the problems identified. The greatest challenge faced by Brazil is currently to create a framework project to develop education, science and technology applied to oceanography and related areas. This framework would strengthen the present working groups and enhance capacity building, allowing a broader Brazilian participation in joint international actions and scientific programs. Recently, the establishment of the National Institutes of Science and Technology (INCTs) for marine science, and the creation of the National Institute of Oceanographic and Hydrological Research represent an exemplary start. However, the participation of the Brazilian academic community in the latest assaults on the frontier of chemical oceanography is extremely limited, largely due to: i. absence of physical infrastructure for the preparation and processing of field samples at ultra-trace level; ii. limited access to oceanographic cruises, due to the small number of Brazilian vessels and/or absence of "clean" laboratories on board; iii. restricted international cooperation; iv. limited analytical capacity of Brazilian institutions for the analysis of trace elements in seawater; v. high cost of ultrapure reagents associated with processing a large number of samples, and vi. lack of qualified technical staff. Advances in knowledge, analytic capabilities and the increasing availability of analytical resources available today offer favorable conditions for chemical oceanography to grow. The Brazilian academic community is maturing and willing to play a role in strengthening the marine science research programs by connecting them with educational and technological initiatives in order to preserve the oceans and to promote the development of society.

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Alpha2-Adrenoceptors: structure and ligand binding properties at the molecular level The mouse is the most frequently used animal model in biomedical research, but the use of zebrafish as a model organism to mimic human diseases is on the increase. Therefore it is considered important to understand their pharmacological differences from humans also at the molecular level. The zebrafish Alpha2-adrenoceptors were expressed in mammalian cells and the binding affinities of 20 diverse ligands were determined and compared to the corresponding human receptors. The pharmacological properties of the human and zebrafish Alpha2--adrenoceptors were found to be quite well conserved. Receptor models based on the crystal structures of bovine rhodopsin and the human Beta2-adrenoceptor revealed that most structural differences between the paralogous and orthologous Alpha2--adrenoceptors were located within the second extracellular loop (XL2). Reciprocal mutations were generated in the mouse and human Alpha2--adrenoceptors. Ligand binding experiments revealed that substitutions in XL2 reversed the binding profiles of the human and mouse Alpha2--adrenoceptors for yohimbine, rauwolscine and RS-79948-197, evidence for a role for XL2 in the determination of species-specific ligand binding. Previous mutagenesis studies had not been able to explain the subtype preference of several large Alpha2--adrenoceptor antagonists. We prepared chimaeric Alpha2--adrenoceptors where the first transmembrane (TM1) domain was exchanged between the three human Alpha2--adrenoceptor subtypes. The binding affinities of spiperone, spiroxatrine and chlorpromazine were observed to be significantly improved by TM1 substitutions of the Alpha2a--adrenoceptor. Docking simulations indicated that indirect effects, such as allosteric modulation, are more likely to be involved in this phenomenon rather than specific side-chain interactions between ligands and receptors.

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Teekkareiden musiikkikerho halusi päivittää valo-ohjauskalustoaan sekä selvittää, olisiko järkevää tehdä ohjauksessa käytettävä konsoli itse. Tässä työssä käsitellään valo-ohjauskonsolin suunnitteluprojektin projektinhallintaa suunnittelun, määrittelyn, tavoitteiden ja työryhmän toiminnan osalta. Työssä tehdään myös valo-ohjauskonsolille suuntaa-antava määrittely, joka tarkoituksena on ottaa huomioon tärkeimpiä sähkölaitteen suunnittelussa huomioon otettavia kriteereitä. Työssä selvitetään, mikä on toimiva työmalli pienelle tutkimusprojektille ja kannattaako pienen organisaation valmistaa valo-ohjauskonsoli itse.

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In recent decades, business intelligence (BI) has gained momentum in real-world practice. At the same time, business intelligence has evolved as an important research subject of Information Systems (IS) within the decision support domain. Today’s growing competitive pressure in business has led to increased needs for real-time analytics, i.e., so called real-time BI or operational BI. This is especially true with respect to the electricity production, transmission, distribution, and retail business since the law of physics determines that electricity as a commodity is nearly impossible to be stored economically, and therefore demand-supply needs to be constantly in balance. The current power sector is subject to complex changes, innovation opportunities, and technical and regulatory constraints. These range from low carbon transition, renewable energy sources (RES) development, market design to new technologies (e.g., smart metering, smart grids, electric vehicles, etc.), and new independent power producers (e.g., commercial buildings or households with rooftop solar panel installments, a.k.a. Distributed Generation). Among them, the ongoing deployment of Advanced Metering Infrastructure (AMI) has profound impacts on the electricity retail market. From the view point of BI research, the AMI is enabling real-time or near real-time analytics in the electricity retail business. Following Design Science Research (DSR) paradigm in the IS field, this research presents four aspects of BI for efficient pricing in a competitive electricity retail market: (i) visual data-mining based descriptive analytics, namely electricity consumption profiling, for pricing decision-making support; (ii) real-time BI enterprise architecture for enhancing management’s capacity on real-time decision-making; (iii) prescriptive analytics through agent-based modeling for price-responsive demand simulation; (iv) visual data-mining application for electricity distribution benchmarking. Even though this study is from the perspective of the European electricity industry, particularly focused on Finland and Estonia, the BI approaches investigated can: (i) provide managerial implications to support the utility’s pricing decision-making; (ii) add empirical knowledge to the landscape of BI research; (iii) be transferred to a wide body of practice in the power sector and BI research community.

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Diplomityössä tutkittiin Fortumin Loviisan ydinvoimalaitoksen ulosvirtauskanaviston ja suurnopeuskosteudenerottimen toimintaa, sekä selvitettiin taustalla olevaa teoriaa ja aiemmin tehtyjä tutkimuksia. Tavoitteena oli ymmärtää ja esittää laitteiden toimintaa, sekä tutkia voiko ulosvirtauskanaviston suorituskykyä parantaa geometrian muutoksilla. Työssä luotiin tutkittaville kohteille geometriat ja laskentahilat, joiden avulla simuloitiin niiden toimintaa eri käyttötilanteissa numeerisen virtauslaskennan avulla. Laskennan reunaehdot saatiin olemassa olevasta prosessimallista ja aiemmista turbiiniselvityksistä. Ulosvirtauskanaviston suorituskyky laskettiin kolmella eri lauhdutinpaineella neljällä eri geometrialla. Geometrian muutokset vaikuttivat selkeästi ulosvirtauskanaviston suorituskykyyn ja sitä saatiin parannettua. Kaksi kolmesta muutoksesta, lisäkanavat ja oikaistu vesilippa, pa-ransivat suorituskykyä. Lokinsiipien poistaminen heikensi ulosvirtauskanaviston toi-mintaa. Suurnopeuskosteudenerottimen mallintaminen jäi lähtötietojen ja ajan puutteen takia hieman tavoitteesta. Sekä ulosvirtauskanaviston että suurnopeuskosteudenerotti-men jatkotutkimusta ja mahdollisia toimenpiteitä varten saatiin arvokasta uutta tietoa.

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Technological innovations, the development of the internet, and globalization have increased the number and complexity of web applications. As a result, keeping web user interfaces understandable and usable (in terms of ease-of-use, effectiveness, and satisfaction) is a challenge. As part of this, designing userintuitive interface signs (i.e., the small elements of web user interface, e.g., navigational link, command buttons, icons, small images, thumbnails, etc.) is an issue for designers. Interface signs are key elements of web user interfaces because ‘interface signs’ act as a communication artefact to convey web content and system functionality, and because users interact with systems by means of interface signs. In the light of the above, applying semiotic (i.e., the study of signs) concepts on web interface signs will contribute to discover new and important perspectives on web user interface design and evaluation. The thesis mainly focuses on web interface signs and uses the theory of semiotic as a background theory. The underlying aim of this thesis is to provide valuable insights to design and evaluate web user interfaces from a semiotic perspective in order to improve overall web usability. The fundamental research question is formulated as What do practitioners and researchers need to be aware of from a semiotic perspective when designing or evaluating web user interfaces to improve web usability? From a methodological perspective, the thesis follows a design science research (DSR) approach. A systematic literature review and six empirical studies are carried out in this thesis. The empirical studies are carried out with a total of 74 participants in Finland. The steps of a design science research process are followed while the studies were designed and conducted; that includes (a) problem identification and motivation, (b) definition of objectives of a solution, (c) design and development, (d) demonstration, (e) evaluation, and (f) communication. The data is collected using observations in a usability testing lab, by analytical (expert) inspection, with questionnaires, and in structured and semi-structured interviews. User behaviour analysis, qualitative analysis and statistics are used to analyze the study data. The results are summarized as follows and have lead to the following contributions. Firstly, the results present the current status of semiotic research in UI design and evaluation and highlight the importance of considering semiotic concepts in UI design and evaluation. Secondly, the thesis explores interface sign ontologies (i.e., sets of concepts and skills that a user should know to interpret the meaning of interface signs) by providing a set of ontologies used to interpret the meaning of interface signs, and by providing a set of features related to ontology mapping in interpreting the meaning of interface signs. Thirdly, the thesis explores the value of integrating semiotic concepts in usability testing. Fourthly, the thesis proposes a semiotic framework (Semiotic Interface sign Design and Evaluation – SIDE) for interface sign design and evaluation in order to make them intuitive for end users and to improve web usability. The SIDE framework includes a set of determinants and attributes of user-intuitive interface signs, and a set of semiotic heuristics to design and evaluate interface signs. Finally, the thesis assesses (a) the quality of the SIDE framework in terms of performance metrics (e.g., thoroughness, validity, effectiveness, reliability, etc.) and (b) the contributions of the SIDE framework from the evaluators’ perspective.

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Chromatin proteins play a role in the organization and functions of DNA. Covalent modifications of nuclear proteins modulate their interactions with DNA sequences and are probably one of the multiple factors involved in the process of switch on/off transcriptionally active regions of DNA. Histones and high mobility group proteins (HMG) are subject to many covalent modifications that may modulate their capacity to bind to DNA. We investigated the changes induced in the phosphorylation pattern of cultured Wistar rat Sertoli cell histones and high mobility group protein subfamilies exposed to 7 µM retinol for up to 48 h. In each experiment, 6 h before the end of the retinol treatment each culture flask received 370 KBq/ml [32P]-phosphate. The histone and HMGs were isolated as previously described [Moreira et al. Medical Science Research (1994) 22: 783-784]. The total protein obtained by either method was quantified and electrophoresed as described by Spiker [Analytical Biochemistry (1980) 108: 263-265]. The gels were stained with Coomassie brilliant blue R-250 and the stained bands were cut and dissolved in 0.5 ml 30% H2O2 at 60oC for 12 h. The vials were chilled and 5.0 ml scintillation liquid was added. The radioactivity in each vial was determined with a liquid scintillation counter. Retinol treatment significantly changed the pattern of each subfamily of histone and high mobility group proteins.

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This study evaluated the fatty acid quantification, proximate and amino acid compositions, antioxidant activity, total phenolic compounds, vitamin E, and mineral contents of new amaranth (BRS Alegria) and quinoa (BRS Piabiru) cultivars which were produced in order to adapt these pseudocereals to the climatic conditions of central-western Brazil. They showed superior levels of protein and total lipids in comparison to their native counterparts. The lipid profile of the amaranth BRS Alegria was revealed to be better than those of other native cultivars. Quinoa BRS Piabiru presented a higher antioxidant capacity and phenolic content than the studied amaranth cultivar, but lower contents of tocopherols. All of the obtained results confirm that these new grains possess an overall amount of nutritional compounds that is better than those reported for many native counterparts of the studied samples. The employed analytical methods in this work contributed to a better understanding of the quinoa BRS Piabiru and amaranth BRS Alegria chemical compositions. Therefore, the diversity and quantity of all of the studied compounds in the samples denote the considerable importance of these grains for food science research area.

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The main objective of this study is to examine the motivations behind sharing information and other content in social media. The goal was also to research how social media has changed information sharing behavior online. The theoretical part of the study covers social media marketing, motivations and Rioux’s framework of Information-Acquiring–and-Sharing in Internet environments. Marketer’s abilities to influence information sharing is explained through the MOA-model. The empirical research was conducted by using deductive research methods to assess Rioux’s framework of IA&S behavior in social media. This study included interviews of 12 respondents. The data was collected and analyzed by using qualitative research methods. This study confirms Rioux’s findings. Everyday information needs motivate information acquiring behavior. The findings show that social and emotional needs for maintaining relationships and the need for participation are considered as the most important internal motivations of sharing information and other content on social media. External motivations include expectations of others, environmental norms, and opportunities to win money. Social media strengthens the motivation for sharing information by offering a platform for satisfying these needs. It has also increased information sharing online due to its ease of use.

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Hyvän syntymän hoidon tavoitteena on turvata synnyttäjän paras mahdollinen terveys, vähentää tarpeetonta puuttumista synnytyksen kulkuun ja mahdollistaa voimaannuttava synnytyskokemus perheelle. Hyvä syntymän hoito ja siihen liittyvä kätilöiden kliinisen hoitotyön osaaminen ei voi kehittyä, ellei hoitotyön käytäntöjä tutkita. Suomalaista hoitotieteellistä syntymän hoitoon liittyvää tutkimusta on vähän. Tämän tutkimuksen tarkoituksena oli kuvata synnytyksen ponnistusvaiheen hoidon käytäntöjä Suomen synnytyssairaaloissa. Lisäksi seurantatutkimuksen avulla selvitettiin, miten ensisynnyttäjät kokivat synnytyksen ponnistusvaiheen, sen aikana saamansa hoidon, ensisynnyttäjien synnytyskokemusta, kivun kokemista, vointia kolmena päivänä synnytyksen jälkeen sekä heidän seksuaaliterveyttään ensimmäisen vuoden aikana synnytyksen jälkeen. Tutkimuksen tavoitteena oli tuottaa tietoa, jonka avulla voidaan kehittää synnytyksen ponnistusvaiheen hoitoa ja lisätä tietoa synnyttäneiden naisten voinnista ja seksuaaliterveydestä. Tutkimuksen ensimmäinen osio toteutettiin poikkileikkaustutkimuksena (2009), johon osallistui Suomen synnytyssairaaloiden synnytysosastoilla työskentelevät kätilöt (N = 662). Tutkimuksen toinen osio toteutettiin seurantatutkimuksena (2009−2011), jossa oli neljä mittausajankohtaa: kolmantena päivänä synnytyksestä sekä kolmen, kuuden ja kahdentoista kuukauden kuluttua synnytyksestä. Tähän osioon osallistui spontaanisti alateitse yhden elävän lapsen (pää tarjoutuvana) synnyttäneet ensisynnyttäjät (N = 453) ja sikiön perätilan vuoksi suunnitellusti keisarileikatut ensisynnyttäjät (N = 84). Aineisto analysoitiin tilastollisin menetelmin. Tutkimustulosten mukaan osa kätilöiden käyttämistä synnytyksen ponnistusvaiheen hoitokäytännöistä ei ole näyttöön perustuvia. Synnytyssairaalan synnytyksen hoidon kulttuuri näyttää siirtyvän mallioppimisen kautta. Ensisynnyttäjät kokivat synnytyksen ponnistusvaiheen hoidon pääsääntöisesti myönteisenä. Alateitse synnyttäneillä ensisynnyttäjillä oli myönteisempi synnytyskokemus ja vähemmän kipua heti synnytyksen jälkeen ja kolmena synnytyksen jälkeisenä päivänä verrattuna keisarileikkauksella synnyttäneisiin ensisynnyttäjiin. Alateitse synnyttäneillä ensisynnyttäjillä kipu ja ompeleet eivät vaikuttaneet haitallisesti vastasyntyneen hoitoon tai imetykseen niin paljon kuin keisarileikkauksella synnyttäneillä ensisynnyttäjillä. Välilihan leikkaus-, repeämä- tai keisarileikkaushaavat olivat täysin parantuneet suurimmalla osalla naisista kolmen kuukauden kuluttua synnytyksestä. Yleisimpiä naisten kokemia oireita ensimmäisen vuoden aikana synnytyksestä olivat emättimen kostumisen vaikeus, yhdyntäkivut, peräpukamat sekä arpikudoksen kipu ja kiristys. Sukupuolinen halukkuus ja tyytyväisyys seksielämään olivat huonompaa ensimmäisen vuoden aikana synnytyksestä verrattuna aikaan ennen raskautta ja synnytystä. Synnytyksen aikaisella hoitotyöllä ja näyttöön perustuvalla synnytyksen ponnistusvaiheen hoidolla on suuri merkitys naisen synnytyskokemukseen, synnytyksen jälkeiseen vointiin ja seksuaaliterveyteen.

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The Baltic Sea is a unique environment that contains unique genetic populations. In order to study these populations on a genetic level basic molecular research is needed. The aim of this thesis was to provide a basic genetic resource for population genomic studies by de novo assembling a transcriptome for the Baltic Sea isopod Idotea balthica. RNA was extracted from a whole single adult male isopod and sequenced using Illumina (125bp PE) RNA-Seq. The reads were preprocessed using FASTQC for quality control, TRIMMOMATIC for trimming, and RCORRECTOR for error correction. The preprocessed reads were then assembled with TRINITY, a de Bruijn graph-based assembler, using different k-mer sizes. The different assemblies were combined and clustered using CD-HIT. The assemblies were evaluated using TRANSRATE for quality and filtering, BUSCO for completeness, and TRANSDECODER for annotation potential. The 25-mer assembly was annotated using PANNZER (protein annotation with z-score) and BLASTX. The 25-mer assembly represents the best first draft assembly since it contains the most information. However, this assembly shows high levels of polymorphism, which currently cannot be differentiated as paralogs or allelic variants. Furthermore, this assembly is incomplete, which could be improved by sampling additional developmental stages.

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Les schémas en annexe ont été réalisés avec le logiciel Adobe Illustrator.

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Cette recherche vise à examiner les relations entre la perception que des membres du personnel enseignant ont des pratiques du leadership transformationnel de la direction d’école, du contexte scolaire et des conditions favorisant leur engagement à implanter le renouveau pédagogique dans leur école. Le schéma conceptuel et le questionnaire qui sous-tendent cette recherche sont une adaptation de ceux élaborés par Yu, Leithwood et Jantzi (2002). Le questionnaire a été complété par 31 membres du personnel enseignant de quatre écoles primaires montréalaises appartenant à des commissions scolaires anglophones et francophones. À partir de ces données, nous avons calculé des moyennes et nous avons comparé les écoles, à l’aide des tests Mann-Whitney, selon leur niveau d’implantation du renouveau pédagogique, leur niveau socioéconomique et la langue de la commission scolaire d’appartenance. De plus, pour compléter nos données quantitatives, nous avons repris quelques citations des entrevues faites auprès des directions de ces écoles que les professeurs du département d’Administration et fondements de l’éducation de l’Université de Montréal, qui font partie du Groupe de recherche sur l’éducation en milieux défavorisés (GRÉMD), ont effectuées dans le cadre d’une autre étude. Les comparaisons des écoles selon leur niveau d’implantation du renouveau pédagogique révèlent que le personnel enseignant des deux écoles en changement se distingue de celui des deux écoles peu engagées dans le changement sur un seul point majeur : il a évalué moins positivement le contexte scolaire, un résultat appuyé par les analyses non paramétriques. Il semble que, dans les écoles qui ont participé à notre étude, le fait de soutenir l’implantation du renouveau pédagogique serait associé à une évaluation plus faible du contexte scolaire ; la culture de l’école et l’environnement étant les conditions les plus touchées. Un autre résultat de cette recherche est le fait que les enseignantes de l’école favorisée ont évalué le contexte scolaire, notamment la culture, l’environnement et les stratégies pour le changement, moins positivement que les enseignantes des écoles défavorisées. Enfin, les comparaisons des écoles en fonction de la langue de la commission scolaire indiquent qu’il n’existe pas de différence significative dans les évaluations faites des trois variables, que les enseignantes travaillent dans une école appartenant à une commission scolaire anglophone ou francophone. Étant donné que l’échantillon d’enseignantes qui a participé à notre étude est modeste, les résultats de cette recherche ne peuvent pas être généralisés, cependant ils pourraient constituer une base pour des recherches ultérieures dans ce domaine.