84 research outputs found

    A Concerted Action of Engrailed and Gooseberry-Neuro in Neuroblast 6-4 Is Triggering the Formation of Embryonic Posterior Commissure Bundles

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    One challenging question in neurogenesis concerns the identification of cues that trigger axonal growth and pathfinding to form stereotypic neuronal networks during the construction of a nervous system. Here, we show that in Drosophila, Engrailed (EN) and Gooseberry-Neuro (GsbN) act together as cofactors to build the posterior commissures (PCs), which shapes the ventral nerve cord. Indeed, we show that these two proteins are acting together in axon growth and midline crossing, and that this concerted action occurs at early development, in neuroblasts. More precisely, we identified that their expressions in NB 6-4 are necessary and sufficient to trigger the formation of the PCs, demonstrating that segmentation genes such as EN and GsbN play a crucial role in the determination of NB 6-4 in a way that will later influence growth and guidance of all the axons that form the PCs. We also demonstrate a more specific function of GsbN in differentiated neurons, leading to fasciculations between axons, which might be required to obtain PC mature axon bundles

    Gastroesophageal Reflux Disease and Helicobacter pylori: What May Be the Relationship?

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    Relationship between Helicobacter pylori (H. pylori) and gastroesophageal reflux disease (GERD) is controversial. We aimed to review the possible relationship between H. pylori infection and GERD. Epidemiological data indicate an inverse relationship between frequency of H. pylori infection and prevalence of GERD and its complications like Barrett's esophagus and esophageal adenocarcinoma. H. pylori eradication in patients with peptic ulcer disease may be associated with increased risk of development of GERD compared with untreated patients. Infection with cagA bearing strains of H. pylori was associated with less severe GERD including endoscopic esophagitis, possibly due to pangastritis leading to hypochlorhydria. Recent studies on inflammatory markers (IL-1ÎČ and IL-1RN) suggest pro-inflammatory genotypes to be protective against development of severe GERD, especially in patients with H. pylori infection. Identification of candidate genes playing an important role in gastric acid secretion and visceral hypersensitivity to the esophageal epithelium might help in early detection of individuals susceptible to develop GERD. Interplay between H. pylori and host factors play an important role in the pathogenesis of GERD

    Ethical awareness in systems development. A case study of the system developerÂŽs responsibility in system development projects

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    MĂ„nga yrken sĂ„ som lĂ€kare och psykologer har en lĂ„ng historia av yrkesutövande. Det lĂ„nga yrkesutövandet har Ă€ven resulterat i att professionen bildat egna, yrkesetiska riktlinjer. IT-branschen som ses som en relativt ung och nĂ„got omogen bransch har Ă€nnu inte nĂ„gra tydliga och konkreta riktlinjer för etik och moral. Det gĂ€ller dĂ„ att skapa diskussioner angĂ„ende etiskt handlande för att bĂ„de öka den etiska medvetenheten men samtidigt stadga riktlinjer. Utvecklingen av IT-branschen gĂ„r idag raskt framĂ„t och denna utveckling medför förĂ€ndring för branschen men Ă€ven för miljön och samhĂ€llet. Syftet med studien Ă€r att utifrĂ„n ett ansvarsperspektiv utreda systemutvecklarens etiska medvetenhet för att dĂ€rigenom kunna ge ett kunskapsbidrag till diskussionen om systemutvecklarens utbildning och yrkesroll. Vi stĂ€ller oss dĂ€rför följande frĂ„ga: Vilka etiska aspekter kan förbĂ€ttra systemutvecklarens utbildning och yrkesroll? För att besvara frĂ„gan sĂ„ har vi utfört en fallstudie dĂ€r vi genomgick ett skarpt systemutvecklingsprojekt för att först testa vĂ„r egna etiska medvetenhet och samtidigt undersöka vilka etiska dilemman en systemutvecklare kan stĂ€llas inför. Vi utförde sedan intervjuer med erfarna systemutvecklare för att ge en kontrast mot oerfarenhet och erfarenhet nĂ€r det kommer till etisk medvetenhet. Undersökning skedde med hjĂ€lp av etiska teorier. Hela studien har utförts med en kvalitativ ansats för att fĂ„ en djupare insikt i forskningsomrĂ„det. Det vi kom fram till i studien var att det inte Ă€r den etiska medvetenheten som spelar sĂ„ stor roll, utan förmĂ„gan att bemöta de etiska dilemman som kan uppstĂ„. De aspekter som visade sig vara av betydelse för detta var; etiska riktlinjer, monetĂ€ra drivkrafter, ansvar samt pĂ„verkningsmöjlighet.Many professions, such as doctors and psychologists, have a long history of work practice which have resulted that these professions have created their own ethical guidelines. The IT profession, which can be viewed as a relative young and somewhat immature profession, have yet to accommodate any clear guidelines regarding ethics. It’s therefore imperative to create discussions regarding ethical actions to raise the ethical awareness and also create ethical guidelines. The development of the IT profession is moving forward at a quick pace and it’s important to understand that this rapid advancement is not only changing the profession but also changing the society and the environment. The purpose of this study is, from a responsibility aspect, to investigate the system developer’s ethical awareness and trough that be able to contribute to the discussion regarding the system developer’s education and profession. To make this contribution we are therefore asking us the following question: Which ethical aspect can help to enhance the system developer’s education and profession? To answer this question we performed a case study where we underwent a live systems development projects. The reason we did this was to test our own ethical awareness and ethical knowledge and also to investigate the kind of ethical dilemmas a system developer can come to face in the profession. Later we made interviews with both experienced and inexperienced system developer’s to be able to present a contrast regarding experienced and inexperienced developers related to ethical awareness. The research was made with ethical theories. For this study we used a qualitative approach in order to get a deeper and richer insight in the research subject. The outcome of the study showed that it wasn’t the ethical awareness that played the most important role, but instead the ability respond to the ethical dilemmas that can arise in the IT profession. The aspects that was of most importance was: ethical guidelines, monetary impulsions, responsibility and the ability to influence. Keywords: Ethics, systems development, responsibility, ethical awareness, systems development project

    Modelling Gene Expression during Ontogenetic Differentiation

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    Various types of recurrent neural networks have been used as models for the regulatory relationships between genes. The neural network is trained on the data from micro-array techniques, each gene corresponds to a neuron in the network. The data from the micro-array technologies has numerous genes, but usually involves few samples, this makes the network heavily under-determined. In this work we will propose a method that can cope with the poorness of the data. We will use a Hopfield-type neural network to model the ontogenetic differentiation of female honeybees. A method that identifies the genes that determine the castes is proposed

    Vibration Monitoring of Fortum’s Hydroelectric Power Plants

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    VibrationsmĂ€tning Ă€r inget nytt fenomen men mĂ„nga företag anser sig Ă€ndĂ„ skeptiskatill den abstrakta metoden. Samma skepticism finns inte vid ett lĂ€karbesök dĂ€r doktornlyssnar efter oljud med sitt stetoskop, Ă€ndĂ„ Ă€r likheterna slĂ„ende. Med dagens teknikĂ€r det möjligt att diagnostisera en maskins olika bestĂ„ndsdelar efter skador genom attanalysera det unika vibrationsmönster de bidrar med. Detta arbete syftar att minska denna barriĂ€r med hjĂ€lp av en introduktion till de olikabegrepp och val som finns inom vibrationsteknisk analys som hjĂ€lpmedel för underhĂ„ll.Slutligen presenteras en implementeringsmall dĂ€r ekonomi och tillgĂ€nglighet anses varamest vitala inför framtida beslut.Even though vibration measurement is not a new phenomenon, many businesses stillremain sceptical towards the somewhat abstract method. Same scepticism does not existwhen you visit the doctor and he uses his stethoscope to listen after abnormalities inthe sound pattern, even though the similarities are striking. With todays technology it ispossible to diagnose a machine’s different parts in search for damages by analysing theunique vibrationpatterns they provide. This study aims to close this gap with the help off an introduction to the different termsand choices that exist in vibration analysis as a tool in preventive maintenance and finallyto present guidelines for implementation where economy and availability is consideredmost pivotal for future decisions

    Managing change in fast-growing companies : a study on governance and critical events

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    Bakgrund: För nystartade företag Àr vÀgen till framgÄng sÀllan okomplicerad. Resan prÀglas ofta av motgÄngar, hinder och utmaningar, framför allt för företag som vÀxer snabbt. MÄnga har bildenav att företag som vÀxer mycket och snabbt enbart Àr förenade med framgÄng och att tillvÀxt Àrvad alla entreprenörer drömmer om. Dock Àr det en komplex och krÀvande uppgift att styrasnabbvÀxande företag. Tidigare forskning har visat hur företag förÀndras nÀr de vÀxer, dÀremotsaknas forskning om vilka styrverktyg som Àr lÀmpliga vid snabb tillvÀxt, hur styrningen förÀndrasöver tid i snabbvÀxande företag samt hur företag bör styras nÀr de vÀxer snabbt med förvÀrv. Denna studie kommer dÀrför att undersöka styrningens förÀndring pÄ ett snabbvÀxande företag dÀr tillvÀxten utgjorts av mÄnga förvÀrv. Syfte: Syftet med studien Àr att öka förstÄelsen för vilka styrverktyg som anvÀnts och hur styrningen förÀndrats över tid i ett snabbvÀxande företag dÀr tillvÀxten utgjorts av mÄnga förvÀrv. Vidare Àmnar studien identifiera vilka kritiska hÀndelser som frÀmst bidragit till styrningens förÀndring. Metod: Denna studie har anvÀnt sig av en kvalitativ forskningsstrategi, en induktiv forskningsansats samt en fallstudie som forskningsdesign. Insamlingen av empiriska data har baserats pÄ primÀrdata frÄn intervjuer samt sekundÀrdata ifrÄn Ärs- och delÄrsrapporter, data frÄn pressmeddelanden pÄ företagets hemsida samt interna dokument. Slutsats: Studien visar att de kritiska hÀndelser som pÄverkat styrningen mest i fallföretaget Àr börsnoteringen, ett ledningsbyte och en omorganisation. Bland de styrverktyg som har anvÀnts i studien har kulturkontroll varit det styrverktyg som förÀndrats mest och dÀrmed haft störst pÄverkan pÄ företagets tillvÀxtresa. Vidare har tre viktiga faktorer identifierats som i kombination med styrningen bidragit till en lyckad förÀndringsresa: dynamiken mellan grundarna och företagskulturen, dynamiken mellan grundarna och tillvÀxten och slutligen dynamiken mellan företagskulturen och tillvÀxten. Background: For startups, the road to success is rarely straightforward. The journey is often characterized by setbacks, obstacles, and challenges, especially for fast-growing companies. Many people have the idea that fast-growing companies are only associated with success and that growth is the dream of all entrepreneurs. However, managing fast-growing companies is a complex and demanding task. Research has previously studied how firms change as they grow, but there is a lack of research on which management controls are appropriate for rapid growth, on how governance changes over time in fast-growing firms, and on how firms should be governed whenthey grow rapidly through acquisitions. Therefore, this study will investigate the change in governance in a fast-growing company where acquisitions have been a large part of the growth. Purpose: The purpose of the study is to increase the understanding of which management controls have been used and how governance has changed over time in a fast-growing company,where acquisitions have been a large part of the growth. Furthermore, the study aims to identify the critical events that mainly contributed to the change in governance. Methodology: This study has used a qualitative research strategy, an inductive research approach and a case study as a research design. The collection of empirical data has been based on primary data from interviews and secondary data from annual and interim reports, data from press releases on the company's website and internal documents. Conclusion: The study shows that the critical events that most affected governance in the case company are the IPO, a change of management and a reorganization. Among the management controls used in the study, cultural control was the type of control that changed the most and thus had the greatest impact on the company's growth journey. Furthermore, three important factors have been identified that, in combination with governance, have contributed to a successful change journey: the dynamics between the founders and the corporate culture, the dynamics between the founders and growth, and finally the dynamics between the corporate culture and growth

    Managing change in fast-growing companies : a study on governance and critical events

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    Bakgrund: För nystartade företag Àr vÀgen till framgÄng sÀllan okomplicerad. Resan prÀglas ofta av motgÄngar, hinder och utmaningar, framför allt för företag som vÀxer snabbt. MÄnga har bildenav att företag som vÀxer mycket och snabbt enbart Àr förenade med framgÄng och att tillvÀxt Àrvad alla entreprenörer drömmer om. Dock Àr det en komplex och krÀvande uppgift att styrasnabbvÀxande företag. Tidigare forskning har visat hur företag förÀndras nÀr de vÀxer, dÀremotsaknas forskning om vilka styrverktyg som Àr lÀmpliga vid snabb tillvÀxt, hur styrningen förÀndrasöver tid i snabbvÀxande företag samt hur företag bör styras nÀr de vÀxer snabbt med förvÀrv. Denna studie kommer dÀrför att undersöka styrningens förÀndring pÄ ett snabbvÀxande företag dÀr tillvÀxten utgjorts av mÄnga förvÀrv. Syfte: Syftet med studien Àr att öka förstÄelsen för vilka styrverktyg som anvÀnts och hur styrningen förÀndrats över tid i ett snabbvÀxande företag dÀr tillvÀxten utgjorts av mÄnga förvÀrv. Vidare Àmnar studien identifiera vilka kritiska hÀndelser som frÀmst bidragit till styrningens förÀndring. Metod: Denna studie har anvÀnt sig av en kvalitativ forskningsstrategi, en induktiv forskningsansats samt en fallstudie som forskningsdesign. Insamlingen av empiriska data har baserats pÄ primÀrdata frÄn intervjuer samt sekundÀrdata ifrÄn Ärs- och delÄrsrapporter, data frÄn pressmeddelanden pÄ företagets hemsida samt interna dokument. Slutsats: Studien visar att de kritiska hÀndelser som pÄverkat styrningen mest i fallföretaget Àr börsnoteringen, ett ledningsbyte och en omorganisation. Bland de styrverktyg som har anvÀnts i studien har kulturkontroll varit det styrverktyg som förÀndrats mest och dÀrmed haft störst pÄverkan pÄ företagets tillvÀxtresa. Vidare har tre viktiga faktorer identifierats som i kombination med styrningen bidragit till en lyckad förÀndringsresa: dynamiken mellan grundarna och företagskulturen, dynamiken mellan grundarna och tillvÀxten och slutligen dynamiken mellan företagskulturen och tillvÀxten. Background: For startups, the road to success is rarely straightforward. The journey is often characterized by setbacks, obstacles, and challenges, especially for fast-growing companies. Many people have the idea that fast-growing companies are only associated with success and that growth is the dream of all entrepreneurs. However, managing fast-growing companies is a complex and demanding task. Research has previously studied how firms change as they grow, but there is a lack of research on which management controls are appropriate for rapid growth, on how governance changes over time in fast-growing firms, and on how firms should be governed whenthey grow rapidly through acquisitions. Therefore, this study will investigate the change in governance in a fast-growing company where acquisitions have been a large part of the growth. Purpose: The purpose of the study is to increase the understanding of which management controls have been used and how governance has changed over time in a fast-growing company,where acquisitions have been a large part of the growth. Furthermore, the study aims to identify the critical events that mainly contributed to the change in governance. Methodology: This study has used a qualitative research strategy, an inductive research approach and a case study as a research design. The collection of empirical data has been based on primary data from interviews and secondary data from annual and interim reports, data from press releases on the company's website and internal documents. Conclusion: The study shows that the critical events that most affected governance in the case company are the IPO, a change of management and a reorganization. Among the management controls used in the study, cultural control was the type of control that changed the most and thus had the greatest impact on the company's growth journey. Furthermore, three important factors have been identified that, in combination with governance, have contributed to a successful change journey: the dynamics between the founders and the corporate culture, the dynamics between the founders and growth, and finally the dynamics between the corporate culture and growth

    Fuktkontroll av en ventilerad platta pÄ mark : Modellering i COMSOL Multiphysics 5.5

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    Krypgrunder i nĂ„gon form har anvĂ€nts som grundkonstruktion i Sverige under lĂ„ngtid. Förr var det torpargrunder som med tiden blev isolerade krypgrunder och plintgrunder. Gemensamt för krypgrundskonstruktioner som Ă€r ventilerade med utomhusluft Ă€r att under sommarhalvĂ„ret blir det förhöjda relativa Ă„nghalter. Syftet med fallstudien Ă€r att studera en uteluftsventilerad konstruktion med vĂ€lisolerat bjĂ€lklag och markisolering. Konstruktionen Ă€r nedgrĂ€vd och ventilationen i grunden sker via en tunn spalt under marknivĂ„. Luftspaltens temperatur och relativa Ă„nghalt Ă€r av intresse för att avgöra om det finns risken för mögel i konstruktionen. En simulering av vĂ€rmeflödet mellan byggnad och mark genomförs i COMSOLMultiphysics 5.5 för att avgöra temperaturfördelningen i konstruktionen. Temperaturfördelningen ligger som grund för faststĂ€llandet av relativ Ă„nghalt i konstruktionens luftspalt. Simuleringen anvĂ€nder klimatdata för ett typĂ„r i GĂ€vle. Simuleringen visar att det Ă€r höga temperaturer i luftspalten Ă„ret runt. Detta ger enrelativ Ă„nghalt som mĂ„nadsmedel pĂ„ 37–77% under ett Ă„r. Den höga temperaturen iluftspalten bidrar till att hĂ„lla konstruktionen torr dĂ„ kritisk relativ Ă„nghalt, 75–80%, inte överstigs under en lĂ€ngre period. Resultat Ă€r förvĂ„nansvĂ€rt positivt med en lĂ„g risk för mögeltillvĂ€xt i konstruktionen.Det finns mĂ„nga antaganden framförallt vilket luftflöde som Ă„terfinns i luftspalten.För att validera resultaten i arbetet sĂ„ bör mĂ€tningar genomföras pĂ„ de tvĂ„ prototyphus som existerar.Crawl spaces in some form have been used as foundations in Sweden for a long time.In the past, it was uninsulated crawl spaces that eventually evolved into insulatedcrawl spaces and open plinth foundations. An increased relative humidity during thesummer is a common problem for crawl spaces that are ventilated with outdoor air. The purpose of the case study is to study an outdoor ventilated structure with wellinsulated floor and ground insulation. The construction is below ground level andthe ventilation takes place via a thin air gap below ground level. The temperatureand relative humidity in the air gap are of interest to determine if there is a risk ofmould growth in the design. A simulation of the heat flow between the building and the ground is carried out inCOMSOL Multiphysics 5.5 to determine the temperature distribution in the design.The temperature distribution is the basis for the determination of relative vaporcontent in the air gap of the structure.The simulation uses climate data for a typicalyear in GĂ€vle. The simulation shows a high temperature in the air gap which gives a relative vaporcontent as a monthly average of 37–77% during a year. The high temperature in theair gap contributes to keeping the structure dry when critical relative humidity, 75–80%, is not exceeded for a longer period of time. The results are surprisingly positive with a low risk of mold growth in the construction.There are many assumptions, in particular, which airflow is found in the airgap. In order to validate the results in the work, measurements should be made onthe two prototype houses that exist

    Maintaining interoperability in open source software : A case study of the Apache PDFBox project

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    Software interoperability is commonly achieved through the implementation of standards for communication protocols or data representation formats. Standards documents are often complex, difficult to interpret, and may contain errors and inconsistencies, which can lead to differing interpretations and implementations that inhibit interoperability. Through a case study of two years of activity in the Apache PDFBox project we examine day-to-day decisions made concerning implementation of the PDF specifications and standards in a community open source software (OSS) project. Thematic analysis is used to identify semantic themes describing the context of observed decisions concerning interoperability. Fundamental decision types are identified including emulation of the behaviour of dominant implementations and the extent to which to implement the PDF standards. Many factors influencing the decisions are related to the sustainability of the project itself, while other influences result from decisions made by external actors, including the developers of dependencies of PDFBox. This article contributes a fine grained perspective of decision-making about software interoperability by contributors to a community OSS project. The study identifies how decisions made support the continuing technical relevance of the software, and factors that motivate and constrain project activity. CC BY 4.0</p
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