| 1. |
- Westerlund, Tina, 1972
(författare)
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Trädgårdsmästarens förökningsmetoder – schema och katalog över förökningsdelar vid vegetativ förökning av fleråriga örtartade växter
- 2013
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The purpose of this licentiate thesis is to gather and classify information about traditional vegetative propagation of perennial herbaceous plants. This thesis is the first, self-contained part of a survey of propagation methods used by horticulturists. The overarching issue concerns horticultural craft practice and knowledge as explanations, understanding and skills in the conditions, processes, and procedures in plant propagation practices. Knowledge of plant propagation is based on a long tradition of horticultural activities in which the transfer of knowledge has mainly been restricted to the working process. However, in recent decades, the number of professional propagators has decreased. As a consequence, there is an increasing risk that some aspects of this knowledge will be lost to future generations. Admittedly, written information about plant propagation is scattered in various sources, but it is difficult to find instructions that clearly describe the various procedures and action steps, and the variants of the same, included in the propagation process. In order to determine and evaluate the relationship between instructions of how work is (or ought to be) performed and plants of various kinds requires either that you have extensive practical experience, or that you have a clear method for organizing, analysing and drawing conclusions about performance in propagation practices. One part of this method is structuring of information. Therefore the question to be considered in this study is: What is the best way to organize collected information on vegetative propagation methods in order for it to function as instructions for the practical work? Information is obtained by observations in nurseries, in dialogue with professional growers and an examination of instructions in written sources. Part of the methodology was that the investigator was involved as an active participant. A key part of the inquiry has therefore been my own propagation trials and experiments carried out with students. The result is a model for sorting and structuring propagation methods based on the plant parts used for vegetative propagation. The model is presented as a scheme and a catalogue. In addition to the aim of constructing the scheme and the catalogue, an additional purpose is to take the first steps towards the propagation instructions in focus in the second part of the study. The paper concludes with a discussion of possible model expansions, as well as how the model can be related to various growth habits. The underlying idea is that the link between reproduction and growth habit may reveal untested combinations of propagation techniques and plant species. It should also be possible to provide answers to why and how the various methods of vegetative propagation work, and how they might evolve.
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| 2. |
- Larsson, Johan, 1990
(författare)
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Guiding Sustainability Transitions: Backcasting, Experimentation and Social learning
- 2019
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Sustainability challenges including climate change, social injustice, resource depletion and biodiversity loss are becoming increasingly apparent. These challenges can be understood as partly resulting from unsustainable socio-technical systems in society, assumed to require transitions to become sustainable in time. When moving beyond more conventional attempts to analyse and describe sustainability challenges, there is an increasing research interest in solutions-oriented and prescriptive approaches to meaningfully engage with sustainability challenges in various contexts. The aim of this thesis is to contribute knowledge on how societal transitions can be guided into desirable and sustainable pathways, where social learning is assumed a key process. The many designs and frameworks for engaging with sustainability transitions that prevail in literature seldom provide insights into the contingent nature of its application in its particular context, the prior knowledge and beliefs of participating actors, or an unpacking of how and why (transformative) social learning processes might unfold. Through inter- and transdisciplinary research and drawing on case studies and ethnographic methods, this thesis includes further development and an empirical evaluation of a backcasting-from-principles process in two settings: a ‘Challenge Lab’ arena that creates space for students to lead sustainability transitions (Paper I), and a regional multi-stakeholder process related to climate policy (Paper II). These studies represent initial attempts to better understand conditions and mechanisms into the kinds of learning that occur in these spaces. Finally, this thesis develops hypotheses on capabilities of sustainability principles in navigating transitions, and particular tools that may be used within and beyond backcasting settings to provide structure in inspiring and supporting conversations on sustainable and desirable futures (Paper III).
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| 3. |
- Boge, Lukas, 1987
(författare)
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Lipid-based liquid crystals as drug delivery vehicles for antimicrobial peptides
- 2017
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The development of antimicrobial resistance is a great challenge within the health sector around the world. The demand for new efficient treatments is alarming in order to treat various bacterial infections in the near future. Antimicrobial peptides (AMPs) are a group of novel antibiotics that have gain more and more attraction the past decade. However, AMPs suffers from relatively low stability due to proteolytic and chemical degradation. As a consequence, carrier systems protecting the AMPs are highly needed for achieving efficient treatments. In this thesis, lyotropic liquid crystalline (LC) structures consisting of cubic glycerol monooleate/water and hexagonal glycerol monooleate/oleic acid/water have been examined as carriers for three AMPs (AP114, DPK-060 and LL-37). Both bulk gels and discrete dispersed structures, i.e. cubosomes and hexosomes have been studied. Moreover, two different peptide loading approaches for the cubosomes were tested and compared; pre- and post-loading. Characterization of the LC structures was performed using small-angle x-ray scattering (SAXS), dynamic light scattering, ζ-potential, and cryogenic transmission electron microscopy (Cryo-TEM) and peptide loading efficacy by liquid chromatography. The antimicrobial effect of the AMP loaded LC nanoparticles (LCNPs) was studied in vitro using minimum inhibitory concentration (MIC) and time-kill assays. Proteolytic protection was investigated by incubating the formulations with two elastases and the antimicrobial effect after proteolysis was studied using radial diffusion assay (RDA). Results showed that the most hydrophobic peptide (AP114) was prone to induce an increase in negative curvature of the bulk cubic LC gel, hence pushing the system towards a hexagonal structure. The most polar peptide (DPK-060) induced a decrease in negative curvature while LL-37 did not change the LC phase at all. The hexagonal LC phase was not affected by any of the AMPs. The cubic pre- and post-loaded LCNPs displayed promising antimicrobial activity, and sometimes could a synergetic effect be observed, resulting in a slightly better activity than the unformulated AMP. The hexagonal LCNPs were found to be very efficient in encapsulating the AMPs, but did not display any antimicrobial effect, indicating insufficient delivery of peptide to the bacteria. Moreover, cubosomes post-loaded with LL-37 was found to protect the peptide from proteolytic degradation, resulting in a significant better bactericidal effect after proteolysis.
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| 4. |
- Maurina Morais, Eduardo, 1989
(författare)
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Synthesis of protic ionic liquids. Challenges and solutions for the synthesis of pure compounds.
- 2022
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The urgent need to diversify our energy matrix is responsible for a renewed interest in fuel cell technology, which can use hydrogen gas, a renewable green fuel, as an energy source. This technology is currently a commercially available option, however, it still requires technological improvements before it can be widely used for different applications. One way this technology could potentially be improved is by increasing its temperature range of operation by developing new, anhydrous proton conducting materials. Protic ionic liquids, which are organic salts with low melting temperatures, are interesting candidates for this application, since they can conduct protons in the operational conditions of fuel cells and without the need of water. These compounds can be synthesized by a simple acid-base neutralization reaction, but certain considerations must be taken in order to obtain high quality (dry and pure) protic ionic liquids. In this thesis, a series of triazolium and imidazolium based protic ionic liquids were synthesized using a solvent-free method designed to address several limitations encountered with other commonly used methods. Using this method, pure (98-99% m/m) and dry (128-553 ppm of water) protic ionic liquids were synthesized (in a laboratory scale) without the need for purification methods that require heating the ionic liquid, hence avoiding the common issue of thermal decomposition. This method was also designed to allow for the accurate measurement of acid and base, and for the controlled mixing of both compounds, which is essential to avoid producing impure protic ionic liquids with excess of either acid or base. The system is consists of only glass and chemically resistant polymer(PTFE and PVDF) parts, which avoids other contaminants that can result from unwanted reactions involving the reagents with common laboratory tools (metallic objects, paper, plastic, etc.). The resulting ionic liquids were carefully analyzed by spectroscopic and thermal analysis methods designed to avoid water absorption, which is known to affect their properties. To complement this experimental characterization, computational chemistry tools were used to assess the ionic liquids’ properties, as well as to assign vibrational modes.
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| 5. |
- Rocksén, Miranda, 1968
(författare)
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Science Enacted in Everyday Life: Studies of On-line and Classroom Practice
- 2012
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis contributes to the field of science education with two studies investigating science literacy in its practice in everyday life. The approach embrace a view on science learning as embedded in the context of situation, resulting in the study of two practices: on-line communication and science classroom. The particularities in ways of interacting between participants and available physical material are analyzed for the purposes of understanding the characters of unfolding science literacy events. A focus on language use enables methods to distinguish science aspects from other aspects in the context of situation and illuminates how ways of knowing science is connected to ways of expression in ongoing processes of learning. The results illustrate how engagement with and intertwinement of science and everyday genres characterizes science literacy events, particularly seen as the reading, writing and talking about science issues being part of everyday life practices. The two studied contexts are compared as arenas for learning with respect to the different opportunities and routes to learning experiences on-line environments and teaching and learning activities exhibit. Conclusions consider the purposeful decisions learners make and how this have influence on expressed views on science and scientific knowledge. Therefore, learning needs to be understood according to the context of each situation. The thesis represents one approach to current challenges in science education and has implications for professionals engaged in education at different levels in schools and outside schools.
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| 6. |
- Granåsen, Magdalena, 1978-
(författare)
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Exploring C2 Capability and Effectiveness in Challenging Situations : Interorganizational Crisis Management, Military Operations and Cyber Defence
- 2019
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Modern societies are affected by various threats and hazards, including natural disasters, cyber-attacks, extreme weather events and inter-state conflicts. Managing these challenging situations requires immediate actions, suspension of ordinary procedures, decision making under uncertainty and coordinated action. In other words, challenging situations put high demands on the command and control (C2) capability. To strengthen the capability of C2, it is vital to identify the prerequisites for effective coordination and direction within the domain of interest. This thesis explores C2 capability and effectiveness in three domains: interorganizational crisis management, military command and control, and cyber defence operations. The thesis aims to answer three research questions: (1) What constitutes C2 capability? (2) What constitutes C2 effectiveness? and (3) How can C2 effectiveness be assessed? The work was carried out as two case studies and one systematic literature review. The main contributions of the thesis are the identification of perspectives of C2 capability in challenging situations and an overview of approaches to C2 effectiveness assessment. Based on the results of the three studies, six recurring perspectives of capability in the domains studied were identified: interaction (collaboration), direction and coordination, relationships, situation awareness, resilience and preparedness. In the domains there are differences concerning which perspectives that are most emphasized in order obtain C2 capability. C2 effectiveness is defined as the extent to which a C2 system is successful in achieving its intended result. The thesis discusses the interconnectedness of performance and effectiveness measures, and concludes that there is not a united view on the difference between measures of effectiveness and measures of performance. Different approaches to effectiveness assessment were identified, where assessment may be conducted based on one specific issue, in relation to a defined goal for a C2 function or using a more exploratory approach.
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| 7. |
- Jørgensen, Mikkel, 1990
(författare)
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Microkinetic Modeling of Nanoparticle Catalysis using Density Functional Theory
- 2017
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Heterogeneous catalysis is vitally important to modern society, and one path towardsrational catalyst design is through atomistic scale understanding. The atomistic scalecan be linked to macroscopic observables by microkinetic models based on first-principlescalculations. With the increasing accuracy of first-principles methods and growing com-putational resources, it has become important to investigate and further develop themethodology of microkinetic modeling, which is the theme of this thesis.First, a procedure for mean-field microkinetic modeling of reactions over extended surfacesis developed, where complete methane oxidation over Pd(100) and Pd(111) is studied asan example. The model reveals how the main reaction mechanisms depend on reactionconditions, and shows poisoning as well as promotion phenomena.Second, the effect of entropy in microkinetic modeling is investigated, where CO oxidationover Pt(111) is used as a model reaction. Entropy is found to affect reaction kineticssubstantially. Moreover, a method named Complete Potential Energy Sampling (CPES)is developed as a flexible tool for estimating adsorbate-entropy.Third, a kinetic Monte Carlo method is developed to bridge the materials gap in het-erogeneous catalysis. The computational cost to map out the complete reaction-energy-landscape on a nanoparticle is high, which is solved herein using generalized coordinationnumbers as descriptors for reaction energies. CO oxidation over Pt is studied, andnanoparticles are found to behave differently than the corresponding extended surfaces.Moreover, the active site is found to vary with reaction conditions.Finally, the reaction orders and apparent activation energies are coupled to the microscalevia the degree of rate control, which enhances the atomistic understanding of reactionkinetics.
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| 8. |
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| 9. |
- Nimmermark, Anders, 1971
(författare)
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Facets of chemical bonding that enhance or encumber conceptual understanding
- 2014
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Chemical bonding is a vast subject, rich in abstract concepts and advanced and less-advanced explanatory models that the learner has to master. In this context, the teaching of chemical bonding at the secondary school level is extremely important, as it has the potential to increase or hinder students’ further understanding of bonding.In the absence of firm knowledge and effective mental models of chemical bonding, it almost impossible to achieve significant results in any chemical field or application. In this work, which combines the pure chemistry of bonding with didactical studies, I have used database searches, questionnaires, interviews, and textbook analyses to investigate some of the more important aspect of chemical bonding.In the field of pure Science, bond length data have been analysed to ascertain the differences in bond strength between neutral and charged ligands in coordination compounds. While the bond strengths differ, the difference is not sufficiently large for the bonds to be classified as different types.In the didactical field, the conceptual models of students in South Africa and Sweden and underlying causes for these mind-sets, have been investigated. The results show that the different curricula and points of emphasis foster different patterns of understanding of the topic. One finding is that 55%–60% of the students exposed to any of the curricula have a molecular view of a salt that can be traced to visual representations of single ions or formula units of a salt. Therefore, it is important to understand how, when, and which models to use, in order to help students build a more advanced understanding of chemical bonding.
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| 10. |
- Jensen, Mikael, 1969
(författare)
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Lärande och låtsaslek - ett kognitionsvetenskapligt utvecklingsperspektiv
- 2007
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Denna licentiatuppsats är en tvärvetenskaplig undersökning kring lärandets relation till låtsaslek. Ur ett kognitionsvetenskapligt perspektiv är förmågan att låtsas något av en gåta. Därför är det särskilt intressant att undersöka hur barnet kan nå denna förmåga. Sker det genom lärande? Resulterar låtsasleken i något lärande? Fyller låtsasleken någon avgörande funktion för barnets framtid som kulturell medlem? Detta är de frågor som driver undersökningen. Forskningsprocessen vilar i grunden på tidigare forskningsresultat inom kognitionsvetenskap eller fält som är direkt relevanta för kognitionsforskning. Uppsatsen innehåller också ny empiri som används i två specifika syften: (1) att exemplifiera och förtydliga de teoretiska resonemangen, (2) att visa på förekomsten av visst lärande och viss låtsaslek från autentiska lekmiljöer. Den empiriska studien är utförd som deltagande observationer vid fyra förskoleavdelningar. Barnen i studien var från 20 månader gamla till drygt sex år. De resultat som denna uppsats särskilt bidrar med består i att skapa en teori som integrerar kognition, emotion och kommunikation. Därtill handlar det om tre särskilda perspektiv på lärande och låtsaslek: (1) Människan är utrustad med fem regulatorer som (a) märker av den emotionella statusen i närmiljön; om hot förekommer saknas förutsättningar för lek, (b) reglerar individens uppmärksamhet; vid låtsassituationer behöver individen vara särskilt uppmärksam på små skillnader, (c) transformerar andras handlingar till egna handlingar genom ett spegelsystem som möjliggör imitation, (d) bidrar till lärande av kulturella normer och regler, (e) förhindrar vissa kulturellt oacceptabla handlingar. (2) Människan tar del i sociala aktiviteter och låtsasleken kan ses som en sådan. Låtsasleken som en social aktivitet bygger på kommunikation av två specifika slag: (a) lekhandlingar som är innehållet i leken; varje handling för leken framåt, (b) leksignaler som hela tiden påminner deltagarna om vilken typ av social aktivitet det rör sig om. Ibland kan lekhandling och leksignal sammanfalla men det kräver inte metakommunikation som andra lekforskare har föreslagit. (3) Genom att betrakta lärande och lek som transfer blir det tydligt vad barnet behöver lära sig för att kunna låtsasleka. Det blir också tydligt vad i leken som utgör ett lärande för framtida situationer. Ett sätt att kunna utföra transfer till och från leken är att lära sig särskilda principer. Åtta sådana föreslås och särskilt en princip, principen om funktionell frihet är sammanflätad med leken och lekutvecklingen. Att utveckla principen om funktionell frihet innebär för barnet att det bättre kan förstå den kultur i vilken det växer upp. Vad som föreslås i denna uppsats är att låtsasleken bidrar till kulturellt lärande och att leken har en potential att utveckla kulturen på sikt.
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