| 1. |
- Åkerstedt, Josefin, 1982-
(författare)
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Tailored Reaction Media for the Synthesis of Subvalent Cluster Compounds
- 2010
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Different synthetic approaches and modifications to reaction media have been applied in order to find new routes to the synthesis of main-group clusters and transition metal compounds. The focus has been on the Group 15 element bismuth and the transition metal palladium. The reactions performed have mainly been Lewis acid-base reactions and the characterization tools used X-ray diffraction and Raman spectroscopy. The Bi5[GaCl4]3 salt, previously known form synthesis using other reaction routes, has been isolated from GaCl3-dichloromethane media. The salt containing the subvalent naked bismuth polycation Bi53+ was isolated from the reduction of bismuth(III) chloride. Quantum chemical calculations on the interaction energies of the isolated bismuth cluster show the dichloromethane-cluster interaction energy to be higher than that between benzene and the cluster. Ionic liquids have, in addition to dichloromethane, been shown to work as alternative reaction media for room-temperature synthesis of the Bi5[GaCl4]3 salt. Three different classes of ionic liquids have been used; phosphonium-, imidazolium- and pyrrolidinium-based salts. The ionic liquids used have been treated with Lewis acids in order to promote cluster formation. In this work three new palladium sandwich compounds have also been isolated, using GaCl3-arene reaction media; [Pd2(Ga2Cl7)(C7H8)2], [Pd2(GaCl4)(C9H12)2]∙C9H12 and [Pd2(Ga2Cl7)(C6H5Cl)2]. Quantum chemical calculations on these palladium sandwiches show the chlorobenzene sandwiching ligands unexpectedly interacting more strongly with the dipalladium unit than the methyl substituted arenes.
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| 2. |
- Arbuthnott, Andrew
(författare)
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Understanding regional renewal and industry cluster emergence processes within the Swedish periphery
- 2010
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- There are many insightful writings revealing that regions within industrialised nations are able to renew their local business environments through building and supporting industry clusters. Such knowledge stems from research based on how to maintain and develop successful industry clusters located within central regions. Although such knowledge is valuable for both researchers and practitioners, little is known about the processes involved when new industry clusters are emerging; and especially when they are emerging in peripheral regions. To that background, the purpose of this licentiate thesis is to develop further understanding of regional renewal and industry cluster emergence within peripheral regions. The thesis is based on a series of covering chapters and three research papers. Each of the three research papers contributes to the aim of this study and the research questions that are brought forward within the covering chapters. With aims of developing theory and providing empirical illustration of regional renewal and industry cluster emergence the research questions used to guide this particular research are: How does a new industry cluster emerge within a peripheral region and what are the main processes involved? What role does the interaction between new regional industry and established regional industry play in facilitating industry cluster emergence? What core co-operative and competitive forces drive such emergence efforts? Relevant empirical material brought forward to help answer these questions is based stems from within the peripheral Swedish county of Västernorrland and specifically centres on the emergence of a new biorefinery industry cluster in the Örnsköldsvik region. A conceptual framework outlining structural-organisational, socio-institutional and cognitive perspectives of regional renewal is employed to help govern the study and aid discussion of the three individual research papers appended. Overall, and in a very condensed format, the papers related to this licentiate thesis reveal that industry cluster emergence within a peripheral region can be supported by bottom-up efforts that encapsulate social movement framing activities, dialectical interplays as well as regional competitive and co-operative forces. In particular, interactions between new regional industry and established industry entities can play a key role in the process; mainly through established actors responding to local resource and legitimacy threats that have potential to reduce the region’s opportunities for renewal. Moreover, new industry actors’ mobilisations provide an ‘anti-thesis’ to local traditional industry that restrain but also trigger development. This is found to be crucial to overcome traditional regional actors’ contestation to new industry entities. As such it seems a set of core processes that interact and shape regional industry cluster emergence can be categorised and described as framing processes, movement mobilisation processes, inter-industry relational processes and dialectical processes. Furthermore prominent regional competitive and competitive forces driving industry cluster emergence are revealed to be intra and inter-regional. Those forces can have strong implications for regional renewal in the periphery. As this research focuses upon how a new regional industry cluster can emerge within a peripheral region dominated by declining traditional industries, that is able, but not without difficulties, to aid regional renewal the thesis contributes to further theoretical and practical understanding of regional renewal and industry cluster emergence theories. Thus, offering relevant implications for future researchers, regional policy makers and industry cluster developers interested in peripheral regional development issues.
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| 3. |
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| 4. |
- Elfving, Anna
(författare)
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Transcriptional regulation of mouse ribonucleotide reductase
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- All living organisms are made of cells and they store their hereditary information in the form of double stranded DNA. In all organisms DNA replication and repair is essential for cell division and cell survival. These processes require deoxyribonucleotides (dNTPs), the building blocks of DNA. Ribonucleotide reductase (RNR) is catalyzing the rate limiting step in the de novo synthesis of dNTPs. Active RNR is a heterodimeric protein complex. In S phase cells, the mouse RNR consists of the R1 and the R2 proteins. The R1/R2 RNR-complex supplies the cell with dNTPs required for DNA replication. Outside S-phase or in non-proliferating cells RNR is composed of R1 and p53R2 proteins. The R1/p53R2 RNR-complex supplies cells with dNTPs required for mitochondrial DNA replication and for DNA repair. An undisturbed dNTP regulation is important since unbalanced dNTP pools results in DNA mutations and cell death. Since unbalanced pools are harmful to the cell, RNR activity is regulated at many levels. The aim of this thesis is to study how the mouse RNR genes are regulated at a transcriptional level. We have focused on the promoter regions of all three mouse RNR genes. Primer extension experiments show that the transcription start of the TATA-less p53R2 promoter colocalizes with an earlier unidentified initiator element (Inr-element). This element is similar to the known Inr-element in the mouse R1 promoter. Furthermore, functional studies of the R1 promoter revealed a putative E2F binding element. This result suggests that the S phase specific transcription of the R1 gene is regulated by a similar mechanism as the R2 promoter which contains an E2F binding site. Finally we have established a method to partially purify the transcription factor(s) binding the upstream activating region in the mouse R2 promoter by phosphocellulose chromatography and affinity purification using oligonucleotides immobilized on magnetic beads. This method will allow us to further study the transcription factors responsible for activating expression of the R2 protein. This method has a potential to be utilized as a general method when purifying unknown transcription factors.
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| 5. |
- Espling, Daniel, 1983-
(författare)
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Metadata Management in Multi-Grids and Multi-Clouds
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Grid computing and cloud computing are two related paradigms used to access and use vast amounts of computational resources. The resources are often owned and managed by a third party, relieving the users from the costs and burdens of acquiring and managing a considerably large infrastructure themselves. Commonly, the resources are either contributed by different stakeholders participating in shared projects (grids), or owned and managed by a single entity and made available to its users with charging based on actual resource consumption (clouds). Individual grid or cloud sites can form collaborations with other sites, giving each site access to more resources that can be used to execute tasks submitted by users. There are several different models of collaborations between sites, each suitable for different scenarios and each posing additional requirements on the underlying technologies.Metadata concerning the status and resource consumption of tasks are created during the execution of the task on the infrastructure. This metadata is used as the primary input in many core management processes, e.g., as a base for accounting and billing, as input when prioritizing and placing incoming task, and as a base for managing the amount of resources allocated to different tasks.Focusing on management and utilization of metadata, this thesis contributes to a better understanding of the requirements and challenges imposed by different collaboration models in both grids and clouds. The underlying design criteria and resulting architectures of several software systems are presented in detail. Each system addresses different challenges imposed by cross-site grid and cloud architectures:The LUTSfed approach provides a lean and optional mechanism for filtering and management of usage data between grid or cloud sites.An accounting and billing system natively designed to support cross-site clouds demonstrates usage data management despite unknown placement and dynamic task resource allocation.The FSGrid system enables fairshare job prioritization across different grid sites, mitigating the problems of heterogeneous scheduling software and local management policies.The results and experiences from these systems are both theoretical and practical, as full scale implementations of each system has been developed and analyzed as a part of this work. Early theoretical work on structure-based service management forms a foundation for future work on structured-aware service placement in cross- site clouds.
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| 6. |
- Gref, Margareta, 1950-
(författare)
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Glomerular filtration rate in adults : a single sample plasma clearance method based on the mean sojurn time
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Glomerular filtration rate (GFR) is a key parameter in evaluating kidney function. After a bolus injection of an exogenous GFR marker in plasma an accurate determination of GFR can be made by measuring the marker concentration in plasma during the excretion. Simplified methods have been developed to reduce the number of plasma samples needed and yet still maintain a high accuracy in the GFR determination. Groth previously developed a single sample GFR method based on the mean sojourn time of a GFR marker in its distribution volume. This method applied in adults using the marker 99m Tc-DTPA is recommended for use when GFR is estimated to be ≥ 30 mL/min. The aim of the present study was to further develop the single plasma sample GFR method by Groth including patients with severely reduced renal function and different GFR markers. Three different GFR markers 51Cr-EDTA, 99mTc-DTPA and iohexol were investigated. Formulas were derived for the markers 51Cr-EDTA and iohexol when GFR is estimated to be ≥ 30 mL/min. For patients with an estimated GFR < 30 mL/min a special low clearance formula with a single sample obtained about 24 h after marker injection was developed. The low clearance formula was proven valid for use with all three markers. The sources of errors and their influence on the calculated single sample clearance were investigated. The estimated distribution volume is the major source of error but its influence can be reduced by choosing a suitable sampling time. The optimal time depends on the level of GFR; the lower GFR the later the single sample should be obtained. For practical purpose a 270 min sample is recommended when estimated GFR ≥ 30 mL/min and a 24 h sample when estimated GFR < 30 mL/min. Sampling at 180 min after marker injection may be considered if GFR is estimated to be essentially normal.
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| 7. |
- Holmberg, Henrik, 1976-
(författare)
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Generalised linear models with clustered data
- 2010
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In situations where a large data set is partitioned into many relativelysmall clusters, and where the members within a cluster have some common unmeasured characteristics, the number of parameters requiring estimation tends to increase with sample size if a fixed effects model is applied. This fact causes the assumptions underlying asymptotic results to be violated. The first paper in this thesis considers two possible solutions to this problem, a random intercepts model and a fixed effects model, where asymptoticsare replaced by a simple form of bootstrapping. A profiling approach is introduced in the fixed effects case, which makes it computationally efficient even with a huge number of clusters. The grouping effect is mainly seen as a nuisance in this paper. In the second paper the effect of misspecifying the distribution of the random effects in a generalised linear mixed model for binary data is studied. One problem with mixed effects models is that the distributional assumptions about the random effects are not easily checked from real data. Models with Gaussian, logistic and Cauchy distributional assumptions are used for parameter estimation on data simulated using the same three distributions. The effect of these assumptions on parameter estimation is presented. Two criteria for model selection are investigated, the Akaike information criterion and a criterion based on a chi-square statistic. The estimators for fixed effects parameters are quite robust against misspecification of the random effects distribution, at least with the distributions used in this paper. Even when the true random effects distribution is Cauchy, models assuming a Gaussian or a logistic distribution regularly produce estimates with less bias.
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| 8. |
- Hussein, Ahmad, 1967-
(författare)
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Swedish trade and trade policies towards Lebanon 1920-1965
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This licentiate thesis examines the development of Swedish–Lebanese trade relations and the changes of significance for Swedish trade towards Lebanon during the period 1920-1965. The aim of the study is to explore how Sweden as representing a small, open Western economy could develop its economic interests in the emerging Middle East market characterised both by promising economic outlooks, and a high degree of political instability during the age of decolonisation, Cold War logic, and intricate commercial and geo-political factors. The study shows that the Swedish trade with Lebanon was very small during the Interwar period. It was neither possible to find any formal Swedish-Lebanese trade agreements before 1945. In the Post-War period, the promotion of Swedish trade and trade policies towards Lebanon witnessed more interests from the both parties. Two categories of explanations were found for the periods of 1946-53 and 1954-65 respectively. In the first period the Swedish-Lebanese trade developed in a traditional direction with manufactured goods being exported from Sweden and agricultural products being exported from Lebanon. Furthermore, there were no trade agreements between the two countries. In the second period, several Lebanese attempts were made to conclude bilateral trade agreement with Sweden in hope to change the traditional trade direction, and to improve the Lebanese balance of trade. Sweden was, however, convinced that Lebanon could never achieve a balanced foreign trade at least not on a bilateral basis. To maintain a fair access to the Lebanese market, the Swedish authorities avoided to conclude any trade agreement with Lebanon. Despite the Lebanese concern on the big trade deficit between the two countries, Sweden managed in increasing the trade volumes to the region of Middle East through the transit link of Lebanon.
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| 9. |
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| 10. |
- Larsson, Anna
(författare)
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Histone modification regulated bysuppressor of Zeste 12 and Ipl1 : Aurora-like kinase in Drosophila
- 2010
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Polycomb group (PcG) proteins are a group of genome wide silencers that are crucial for many processes during the development. In Drosophila PcG proteins are organised into four different complexes: PRC1, PRC2, PhoRC and PR-DUB. PRC2 consists of four core proteins: Su(z)12, E(z), Esc and Nurf. E(z) is the only known proteins with a known function, it possess a methyltransferase activity that specifically methylates lysine 27 on histone 3 (H3K27). A novel PcG gene was identified in 2001 in screen for modifiers of zeste-white interaction. This gene suppressed zeste’s repression of white and gave it the name Suppressor of zeste 12 (Su(z)12). The Su(z)12 gene is alternatively spliced into two transcripts; a 4.1 kb mRNA called Su(z)12A and a 3.7 kb mRNA called Su(z)12B. These transcripts are translated into two isoforms; a 95 kDa Su(z)12A protein and 100 kDa Su(z)12B protein. These isoforms show a sequence similarity of 95% and the only difference is the C-terminal end. During development these two isoforms are present at different levels. Interaction of the two isoforms with the other core components in PRC2 showed that only Su(z)12B interacts with Nurf. Also the two isoforms showed interaction with each other with the exception of a single copy of Su(z)12A that couldn´t interact with Su(z)12B. Overexpression of Su(z)12B in vivo caused lethality and homeotic transformations. Aurora kinases belong to a conserved family of serine/threonine kinases that are important for many processes in mitotsis, such as spindle formation, chromosomal segregation and cytokinesis. Aurora kinases are overexpressed in many human cancers and inhibitors of Aurora A and Aurora B has shown to inhibit growth and induce apoptosis. There are three Aurora kinases in vertebrates; Aurora A, Aurora B and Aurora C and although they are highly similar, they have different roles and location during mitosis. Aurora B is a chromosomal passenger protein and forms the chromosomal passenger complex with INCENP, Survivin and Borealin. Depletion of Aurora B causes severe effects in mitosis and lead to large cells with several nuclei and polyploidy. The Drosophila homologue of Aurora B is called IpI1-like-Aurora kinase (ial). The c-Myc transcription factor, or its relatives N-Myc and L-Myc, are also overexpressed in many, if not all human cancers. Drosophila has only one Myc protein, dMyc, which is encoded by the diminutive (dm) locus. In Drosophila, dMyc is mostly associated with size and growth regulation and depletion of dm results in endoreplication and growth arrest in early development. Previous work has shown that mammalian c-Myc induces Aurora A and Aurora B kinases. When Myc-driven lymphomas are treated with Aurora B inhibitors, cells are accumulated in G2/M phase and apoptosis is induced. Here we show that these conserved proteins have a potential connection in Drosophila as well since knockdown of ial causes severe phenotypes and leads to larger cells. When ial is knocked down or when dMyc is overexpressed the flies become smaller. Interestingly however transgenic flies which overexpress dMyc and knock down ial exhibit a different pheontype - the flies become bigger. This showing evidence that a relationship between Myc and Aurora B is evolutionary conserved down to Drosophila.
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