501 research outputs found

    Analysis Of Flowering Time, Hybrid Vigor, Yield, And Lodging In Maize

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    Maize (Zea mays L.) is an important crop and an excellent model organism to study genetic systems. It captures remarkable diversity, which can be observed on both the genotypic and phenotypic level. Because of its diversity, maize responded very effectively to artificial selection during domestication and improvement. Maize adapted to very diverse environments. This adaptation has been possible through heritable changes in flowering time, responses to photoperiod and temperature, and plant architecture. Understanding the underlying architecture of these traits will allow us to utilize all the variation offered and increase productivity for a more sustainable agriculture. The following studies focus on analysis of three different traits. First, is a reanalysis of one of the first generation structured association mapping studies of the Dwarf8 locus with flowering time, using new mapping populations and statistical approaches. This trait is highly correlated with population structure, and we found that basic structured association methods overestimate the phenotypic effect in the region, while mixed model approaches perform better. Combined with analysis of the maize NAM population, it is concluded that the QTL effects at the general location of the d8 locus are from extended haplotypes and that d8 is not associated with flowering time. Second, hybrids were developed using the NAM inbred population crossed to a common tester to examine hybrid vigor in terms of plant height and flowering time, as well as yield. A number of QTL were identified for all three traits using joint linkage mapping. Additionally, reasonable prediction accuracies (~0.55) were obtained using ridge regression in the hybrids. This study gives us a better understanding of yield and hybrid vigor. Last, damage caused by lodging is a significant problem in maize production, resulting in 5-20 % annual loss in yield. In this study, more than 1,500 diverse inbred lines crossed to a common tester were evaluated across multiple environments. Due to a large sample size and despite multiple environments with lodging events occurring at different points in time, we were able to utilize joint linkage mapping to identify a number of QTL with small effects for lodging

    Discovering and Assessing Enterprise Architecture Debts

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    The term Enterprise Architecture (EA) Debts has been coined to grasp the difference between the actual state of the EA and its hypothetical, optimal state. So far, different methods have been proposed to identify such EA Debts in organizations. However, these methods either are based on the transfer of known concepts from other domains to EA or are time and resource intensive. To overcome these shortcomings, we propose an approach that uses an interview format to identify EA Debts in enterprises and a method that allows a qualitative assessment of identified EA Debts. The proposed approach is supported by the designed framework that consists of an interview format and a process for determining thresholds of certain EA Smells

    Evaluation of the dao1 gene as a selectable marker in transformation of apple rootstock M26 as well as transformation of a vector containing GA20 oxidase gene into Agrobacterium

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    The aim of this project was to evaluate the possibility to use D-alanine as a selective marker instead of commonly used antibiotics and herbicides in transformation of apple rootstock M26. The transformation was carried out using Agrobacterium tumefaciens strain C58C1(pGV3101) containing the vector pPCV70:dao1. The vector contained the dao1 gene resistant to D-amino acids and the nptII gene resistant to antibiotic, kanamycin. The dao1 encodes for the enzyme D-amino-acid oxidase (DAAO). The enzyme detoxifies D-amino acids, such as, D-alanine, which are harmful to plants. The transformed explants were grown on medium containing increased concentrations of D-alanine, with a starting concentration of 1.2 mM. Eight putative transgenic clones were obtained from the selection medium. However, further molecular analyses have to be carried out to confirm the result. A second experiment was performed to transform the GA20 oxidase gene into A. tumefaciens to get a ready-to-use transformation vector. The vector containing the GA20 oxidase gene was transformed into the A. tumefaciens strain C58C1(pGV3850). DNA from the strain was isolated and digested. The result was visualized on an agarose gel under UV light. The conclusion of the experiment is that the vector containing GA20 oxidase gene has been transformed into the strain C58C1.Syftet med detta projekt var att undersöka möjligheten att vid transformering av äpplegrundstammen M26 genomföra selektion med hjälp av D-aminosyra (D-alanin) istället för andra vanligt förekommande selektionsämnen, så som antibiotika och herbicider. Transformeringar med D-alanin som selektionsämne genomfördes, med Agrobacterium tumefaciens stammen C58C1(pGV3101) innehållande vektorn pPCV70:dao1. Vektorn innehöll även genen nptII, som ger de transformerade explantaten resistans mot antibiotika, kanamycin. dao1 genen kodar för enzymet D-amino-acid oxidase (DAAO). Enzymet bryter ner det giftiga ämnet D-alanin till ofarliga ämnen för växten. De transformerade explantaten odlades på medium innehållande ökande koncentration av D-alanin, med utgångskoncentrationen 1.2 mM. Åtta putativa transformerade kloner selekterades på selektionsmediet. Ytterligare molekylära analyser måste dock genomföras för att bekräfta resultaten. Försök genomfördes även för att transformera en vektor innehållande GA20 oxidas genen i A. tumefaciens, för att få fram en vektor färdig för användning vid transformering av växter. Vektorn innehållande GA20 oxidas genen och nptII genen transformerades in i A. tumefaciens stammen C58C1(pGV3850). DNA från A. tumefaciens var sedan isolerad och fragmenterad. Resultatet visualiserades på en agarose gel under UV ljus. Slutsatsen av försöket är att vektorn transformerats in i A. tumefaciens stammen C58C1

    Разработка испытательно-отладочного программно-аппаратного комплекса на основе ICPDASPCI-1602

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    Материалы XIII Междунар. науч.-техн. конф. студентов, магистрантов и молодых ученых, Гомель, 25–26 апр. 2013

    Snus use and risk of schizophrenia and non-affective psychosis

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    AbstractBackgroundRecent studies suggest a possible causal role for smoking in schizophrenia and psychosis. Most studies have focused on cigarette smoking, the most common form of tobacco use, but other forms of tobacco exist, including smokeless products such as Swedish snuff (or “snus”).MethodsWe explored whether snus use is associated with schizophrenia and non-affective psychotic illness in a large Swedish registry data set. The majority of participants were aged 18 or 19 at the time of assessment.ResultsWe observed a positive association between snus use and odds of schizophrenia in all analyses, but the magnitude of the association was small and the confidence interval wide, consistent with no association (fully adjusted HR 1.03, 95% 0.70–1.54). A similar pattern was observed for non-affective psychosis, but the magnitude of the association was somewhat greater and the confidence intervals narrower, so that these analyses provided stronger statistical evidence for this association (fully adjusted HR 1.22, 95% CI, 1.00–1.48).ConclusionsOur results therefore provide modest evidence for an association between snus use and risk for non-affective psychosis. This is consistent with emerging evidence from a range of studies and methodologies that tobacco use may be a risk factor for psychotic illness. However, our results provide some evidence against the hypothesis that it is the burnt products of cigarette smoke that are psychotogenic

    Hållbarhet i värdekedjan - Faktorer som påverkar företags arbete med hållbarhet

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    Sammanfattning Examensarbetets titel: Hållbarhet i värdekedjan – faktorer som påverkar företags arbete med hållbarhet Seminariedatum: 2014-06-04 Kurs: FEKH19 Examensarbete i Strategic Management på kandidatnivå, 15 HP Författare: Sara Ahlberg, Marielle Gomez, Frida Larsson Handledare: Merle Jacob Nyckelord: hållbarhet, värdekedjan, CSR, möjliggörande faktorer, café- och restaurangbranschen Syfte: Syftet med uppsatsen är att undersöka vilka faktorer som påverkar företags möjlighet att arbeta med hållbarhet i sin värdekedja. Metod: Uppsatsen har via en abduktiv ansats tillämpat en kvalitativ metod. Med hjälp av en multipel fallstudie på fem företag i café- och restaurangbranschen har empiri samlats in genom semi-strukturerade intervjuer och kompletterande dokumentinsamling. Genom mönsterpassning har teorin jämförts med den insamlade empirin. Teoretiska perspektiv: Teorin grundar sig i Porters värdekedja och därefter en diskussion som applicerar hållbarhet i denna. Med utgångspunkt i en komprimerad version av Porters värdekedja har faktorer identifierats som möjliggör företags hållbarhetsarbete. Fyra faktorer som övergripande påverkar företags möjlighet till att arbeta med hållbarhet har identifierats: generisk strategi, underliggande motiv, konsekvens och transparens. Därefter har sex faktorer som påverkar möjligheten till att arbeta hållbart och kan kopplas till en specifik del i värdekedjan identifierats: leverantörsval, affärsrelationer, drivande ledare, innovation, storlek och kundpreferenser. Empiri: Utifrån de semi-strukturerade intervjuerna med vart och ett av fallföretagen genererades ett empiriskt material som utgjorde grunden för undersökningen, detta kompletterades med information från respektive fallföretags hemsidor. Resultatet visar hur de övergripande och resterande faktorerna påverkar företagens möjlighet att arbeta med hållbarhet i olika mån. Slutsats: Resultaten från undersökningen visar att följande faktorer påverkar företags möjlighet att i olika grad arbeta med hållbarhet i värdekedjan: underliggande motiv, transparens, leverantörsval, affärsrelationer, innovation, storlek och kundpreferenser