Overexpression of vesicle-associated membrane protein PttVAP27-17 as a tool to improve biomass production and the overall saccharification yields in Populus trees

Background Bioconversion of wood into bioproducts and biofuels is hindered by the recalcitrance of woody raw material to bioprocesses such as enzymatic saccharification. Targeted modification of the chemical composition of the feedstock can improve saccharification but this gain is often abrogated by concomitant reduction in tree growth. Results In this study, we report on transgenic hybrid aspen (Populus tremula x tremuloides) lines that showed potential to increase biomass production both in the greenhouse and after 5 years of growth in the field. The transgenic lines carried an overexpression construct for Populus tremula x tremuloides vesicle-associated membrane protein (VAMP)-associated protein PttVAP27-17 that was selected from a gene-mining program for novel regulators of wood formation. Analytical-scale enzymatic saccharification without any pretreatment revealed for all greenhouse-grown transgenic lines, compared to the wild type, a 20-44% increase in the glucose yield per dry weight after enzymatic saccharification, even though it was statistically significant only for one line. The glucose yield after enzymatic saccharification with a prior hydrothermal pretreatment step with sulfuric acid was not increased in the greenhouse-grown transgenic trees on a dry-weight basis, but increased by 26-50% when calculated on a whole biomass basis in comparison to the wild-type control. Tendencies to increased glucose yields by up to 24% were present on a whole tree biomass basis after acidic pretreatment and enzymatic saccharification also in the transgenic trees grown for 5 years on the field when compared to the wild-type control. Conclusions The results demonstrate the usefulness of gene-mining programs to identify novel genes with the potential to improve biofuel production in tree biotechnology programs. Furthermore, multi-omic analyses, including transcriptomic, proteomic and metabolomic analyses, performed here provide a toolbox for future studies on the function of VAP27 proteins in plants

Synoptic analysis of a decade of daily measurements of SO2 emission in the troposphere from volcanoes of the global ground-based Network for Observation of Volcanic and Atmospheric Change

Volcanic plumes are common and far-reaching manifestations of volcanic activity during and between eruptions. Observations of the rate of emission and composition of volcanic plumes are essential to recognize and, in some cases, predict the state of volcanic activity. Measurements of the size and location of the plumes are important to assess the impact of the emission from sporadic or localized events to persistent or widespread processes of climatic and environmental importance. These observations provide information on volatile budgets on Earth, chemical evolution of magmas, and atmospheric circulation and dynamics. Space-based observations during the last decades have given us a global view of Earth's volcanic emission, particularly of sulfur dioxide (SO2). Although none of the satellite missions were intended to be used for measurement of volcanic gas emission, specially adapted algorithms have produced time-averaged global emission budgets. These have confirmed that tropospheric plumes, produced from persistent degassing of weak sources, dominate the total emission of volcanic SO2. Although space-based observations have provided this global insight into some aspects of Earth's volcanism, it still has important limitations. The magnitude and short-term variability of lower-atmosphere emissions, historically less accessible from space, remain largely uncertain. Operational monitoring of volcanic plumes, at scales relevant for adequate surveillance, has been facilitated through the use of ground-based scanning differential optical absorption spectrometer (ScanDOAS) instruments since the beginning of this century, largely due to the coordinated effort of the Network for Observation of Volcanic and Atmospheric Change (NOVAC). In this study, we present a compilation of results of homogenized post-analysis of measurements of SO2 flux and plume parameters obtained during the period March 2005 to January 2017 of 32 volcanoes in NOVAC. This inventory opens a window into the short-term emission patterns of a diverse set of volcanoes in terms of magma composition, geographical location, magnitude of emission, and style of eruptive activity. We find that passive volcanic degassing is by no means a stationary process in time and that large sub-daily variability is observed in the flux of volcanic gases, which has implications for emission budgets produced using short-term, sporadic observations. The use of a standard evaluation method allows for intercomparison between different volcanoes and between ground- and space-based measurements of the same volcanoes. The emission of several weakly degassing volcanoes, undetected by satellites, is presented for the first time. We also compare our results with those reported in the literature, providing ranges of variability in emission not accessible in the past. The open-access data repository introduced in this article will enable further exploitation of this unique dataset, with a focus on volcanological research, risk assessment, satellite-sensor validation, and improved quantification of the prevalent tropospheric component of global volcanic emission

Frihet och kontroll. En studie i styrning av postbyråkratiska organisationer

Vi har i vår uppsats studerat frihet och kontroll i postbyråkratiska organisationer. Enligt förespråkare för demokratiska företag ger denna nya organisationsform de anställda större frihet samtidigt som kontrollen minskar. Men en organisation förutsätter styrning och kontroll, var har då kontrollen tagit vägen? Vi använder det brasilianska företaget Semco som exempel på ett postbyråkratiskt företag och tittar på hur de arbetar rent teoretiskt med frihet och kontroll. Semcos VD Ricardo Semler har skrivit flera böcker om hur han förändrade Semco från ett auktoritärt och byråkratiskt företag med motivations- och lönsamhetsproblem till ett organiskt och dynamiskt företag där de anställda känner sig delaktiga och längtar efter att gå till jobbet på morgonen. Genom att analysera Semco ur ett kontroll- och frihetsperspektiv tittar vi på vad som hände efter omorganiseringen till ett postbyråkratiskt företag. Det vi kommer fram till är att kontrollen snarare har ökat till följd av att den flyttats från mellanchefsnivå ned till samtliga individer i organisationen. Genom att omdefinera frihetsbegreppet har dock människans frihet i organisationen till trots ökat, men inte om man ser till den klassiska definitionen av frihet

Aspects of the recursive projection method applied to flow calculations

In this thesis, we have investigated the Recursive Projection Method, RPM, as an accelerator for computations of both steady and unsteady flows, and as a stabilizer in a bifurcation analysis. The criterion of basis extraction is discussed. It can be interpreted as a tolerance for the accuracy of the eigenspace spanned by the identified basis, alternatively it can be viewed as a criterion when the approximative Krylov sequence becomes numerically rank deficient. Steady state calculations were performed on two different turbulent test-cases; a 2D supersonic nozzle flow with the Spalart-Allmaras 1-equation model and a 2D sub-sonic airfoil simulation using the κ - ε model. RPM accelerated the test-cases with a factor between 2 and 5. In multi-scale problems, it is often of interest to model the macro-scale behavior, still retaining the essential features of the full systems. The ``coarse time stepper'' is a heuristic approach for circumventing the analytical derivation of models. The system studied here is a linear lattice of non-linear reaction sites coupled by diffusion. After reformulation of the time-evolution equation as a fixed-point scheme, RPM coupled with arc-length continuation is used to calculate the bifurcation diagrams of the effective (but analytically unavailable) equation. Within the frame-work of dual time-stepping, a common approach in unsteady CFD-simulation, RPM is used to accelerate the convergence. Two test-cases were investigated; the von Karman vortex-street behind a cylinder at Re=100, and the periodic shock oscillation of a symmetric airfoil at M ∞ = 0.76 with a Reynolds number Re=11 x 106. It was believed that once a basis had been identified, it could be retained for several steps. The simulations usually showed that the basis could only be retained for one step. The need for updating the basis motivates the use of Krylov methods. The most common method is the (Block-) Arnoldi algorithm. As the iteration proceeds, Krylov methods become increasingly expensive and restart is required. Two different restart algorithm were tested. The first is that of Lehoucq and Maschhoff, which uses a shifted QR iteration, the second is a block extension of the single-vector Arnoldi method due to Stewart. A flexible hybrid algorithm is derived combining the best features of the two.QC 20101015</p

Användaracceptans för Web 2.0

Web 2.0 har blivit ett vanligt förekommande ord ute på Internet och i datorrelaterad press. Men vad innebär detta egentligen? Ordet innebär i grund och botten en attitydförändring som har med hur Internetanvändare använder Internet och dess applikationer att göra. Det råder dock delade meningar om vad, vilka tekniker och applikationer, som kan räknas till Web 2.0. I detta arbete reder vi ut begreppet tydligare för att skapa oss en bättre förståelse för ordet och dess innebörd. Detta gör vi för att kunna identifiera faktorer som påverkar huruvida användare av Internet vill ta till sig de nya applikationer som Web 2.0 för med sig. Detta är även vårt huvudsyfte med arbetet. Genom att vi sedan jämför Web 2.0 med ”hur man brukat Internet tidigare” kan vi identifiera det som är nytt med Web 2.0. Det nya anser vi vara ett samarbetsperspektiv, ett aktivt givande och tagande av information/kunskap/erfarenheter mm. Denna nyvunna kunskap har vi sedan använt oss av när vi har sökt efter teori. Dessa teorier har resulterat i en egen undersökningsmodell. Med hjälp av teorin och den, utifrån teorin, utformade empiriska undersökningen, bestående av semi-strukturerade intervjuer, har vi försökt utreda vårt huvudsyfte med arbetet. Resultatet från vår respondentgrupp visar på att det finns ett par viktiga faktorer som är grundläggande och viktiga när det gäller acceptans av Web 2.0 applikationer. Vad gäller det aktiva deltagandet, som Web 2.0 innebär, ser vi dock en tydlig tendens att våra respondenter inte är beredda att ta till sig detta sätt att bruka Internet i dagsläget. Det verkar som Web 2.0 applikationerna måste vara riktade mot ett för respondenterna specifikt särintresse för att de skall vara intresserade av att aktivt delta

Självförtroende, ångestbenägenhet, motivationsklimat bland studenter på Lunds universitet.

The purpose of the study was to investigate the relationship between self-efficacy, trait anxiety and motivational climate when it comes to students at Lund University (n=121). A quantitative survey was performed online with General Self-Efficacy Scale (GSE), State Trait Anxiety Inventory (STAI) and Motivational Climate at Work Questionnaire (MCWQ) as the measuring instruments. Although multiple regression analysis showed that trait anxiety is indeed a significant predictor (p<.001) when explaining self-efficacy, the same could not be said about the motivational climate. In a similar manner, a partial correlation showed that the motivational climate didn’t affect the relationship between self-efficacy and trait anxiety. The correlation coefficient was the same (r=-.66) when controlling for motivational climate. A t-test showed no significant difference in trait anxiety between students at the Faculty of Social Sciences and the Faculty of Law. We did however find a significant result when comparing students’ scores for motivational climate. Students at the Faculty of Law scored significantly higher (p<.001) on performance oriented motivational climate, and significantly lower (p=.007) on mastery oriented motivational climate, compared to students at the Faculty of Social Sciences. In conclusion, the motivational climate in a university setting needs further analysis with more complex designs than what we have in our study. Keywords: self-efficacy, anxiety, motivational climate, students, higher educationStudien syftade till att undersöka förhållandet mellan self-efficacy, trait anxiety och motivationsklimat hos studenter på Lunds Universitet (n=121). En kvantitativ enkätundersökning genomfördes online med mätinstrumenten General Self-Efficacy Scale (GSE), State Trait Anxiety Inventory (STAI) samt Motivational Climate at Work Questionnaire (MCWQ). En multipel regressionsanalys visade att trait anxiety är en signifikant prediktor (p <,001) för att förklara self-efficacy, men att motivationsklimatet inte hade någon påverkan på variabeln. På samma sätt så visade en partiell korrelation att motivationsklimatet inte hade en påverkan på sambandet mellan self-efficacy och trait anxiety, då korrelationskoefficienten var densamma efter att kontroll för motivationsklimatet gjordes (r=-,66). Ingen signifikant skillnad i trait anxiety hittades i det t-test som gjordes för att se skillnader mellan den samhällsvetenskapliga- och juridiska fakulteten. Samma test visade dock på en signifikant skillnad i upplevelsen att tillhöra ett visst motivationsklimat, då både det resultatinriktade- (p <,001) och uppgiftsinriktade motivationsklimatet (p=,007) skilde sig åt mellan fakulteterna. Motivationsklimatet behöver alltjämt undersökas ytterligare i universitetsmiljö med designer som är mer komplexa än den vi har använt oss av i denna studie. Nyckelord: self-efficacy, ångest, motivationsklimat, studenter, universite

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Vilka faktorer har betydelse för ett företags beslut att underkasta sig revision?

Since 1983 all Swedish companies are legally obliged to allow themselves to be audited. Recently the question of whether small companies should be subject to this or not has frequently been discussed. Many find it superfluous and think it ought to be abolished. In England small companies no longer have to be audited. However, in a study by Jill Collis it has been shown that a large number of companies choose to be audited although there is no obligation for them to do so. They imply that there are other factors which influence the company’s choice of whether to be audited or not. The purpose of our study is to explain on which factors can affect a small company’s decision to be audited or not. Our theories have been formulated by studying institutional and economical relations in accountancy. The research was carried out by means of telephone interviews on respondents of 250 companies which are classed as small companies in accordance with EC regulations. Our data was subsequently tested in SPSS. Only three of our eleven hypotheses cannot be falsified so far. The factors that explains a company does choose to be audited is board competition, bonus system and the size of the company. In certain hypotheses a tendency to correlation can be seen, but these cannot be statistically verified