Strength tests of shell bedded autoclaved aerated concrete.

In this master thesis, the properties of shell bedded autoclaved aerated concrete (AAC) are investigated. There are reasons to believe that the values for flexural, compressive and shear strength in the Swedish regulations are on the low side. The work within this master thesis consists of determining the characteristic values based on experimental tests. The test results indicate that the values in the Swedish code BKR 2003, at least for the flexural strength might be on the low side. Regarding shear and compressive strength, which had values close to Swedish regulations, further tests are necessary to draw any conclusions

Child Witness Policy: Law Interfacing with Social Science

The number of children testifying in court has posed serious practical and legal problems for the judicial system. One problem confronting the courts is how to protect children from experiencing the psychological trauma resulting from face-to-face confrontation with a defendant who may have physically harmed the child or threatened future harm to the child

Homalg: A meta-package for homological algebra

The central notion of this work is that of a functor between categories of finitely presented modules over so-called computable rings, i.e. rings R where one can algorithmically solve inhomogeneous linear equations with coefficients in R. The paper describes a way allowing one to realize such functors, e.g. Hom, tensor product, Ext, Tor, as a mathematical object in a computer algebra system. Once this is achieved, one can compose and derive functors and even iterate this process without the need of any specific knowledge of these functors. These ideas are realized in the ring independent package homalg. It is designed to extend any computer algebra software implementing the arithmetics of a computable ring R, as soon as the latter contains algorithms to solve inhomogeneous linear equations with coefficients in R. Beside explaining how this suffices, the paper describes the nature of the extensions provided by homalg.Comment: clarified some points, added references and more interesting example

Evidence for the utilization of host tRNA(m5 U)methylase to modify tRNA coded by phage T4

Mutants of Escherichia coli defective only in the biosynthesis of 5-methyluridine (ribothymidine) in their transfer ribonucleic acid (tRNA) were employed to investigate whether phage T4 induces its own tRNA (m5U)methylase and whether T4-specific tRNA contains 5-methyluridine. The amounts of other methylated derivatives in the T4-specific tRNA were also determined. The results establish that T4-specific tRNA contains 5-methyluridine, and that there is an absolute requirement for a functional host tRNA(m5U)methylase to undertake this modification. Comparison of several physical properties of the host enzyme before and after phage T4 infection did not suggest any phage-directed alteration of the enzyme. The distribution of the methylated constituents in T4-specific tRNA is distinguishable from that in host tRNA. This change, however, may simply reflect a different population of tRNA chains produced by the T4 phage, rather than some change in the tRNA methylase activity of the host.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33911/1/0000176.pd

Introduction: Studying Successful Public Policy in the Nordic Countries

publishedVersionPeer reviewe

Novella 2.0: A Hypertextual Architecture for Interactive Narrative in Games

The hypertext community has a history of research in Interactive Digital Narrative (IDN), including experimental works and systems to support authoring. Arguably the most prevalent contemporary form of IDN is within the world of computer games where a mixture of large-scale commercial works and smaller indie experimental pieces continue to develop new forms of interactive storytelling. We can explore these pieces through the lens of hyper- textual theory and support them with hypertextual architectures, but there are unique challenges within modern game-based storytelling that these frameworks sometimes struggle to capture on a content level, leaving us in some cases with insufficient models and vocabulary. In this paper, we build upon previous work by presenting a discussion on techniques of modeling video game narrative. This is followed by thorough presentation and demonstration of our game-centric theoretical model of interactive narrative, Novella 2.0, which builds upon our previous contributions. This model is then positioned within a novel architecture for the authoring, interchange, integration, and simulation of video game narrative. We present alongside the architecture four key innovations towards supporting game narrative. We include support for Discoverable Narrative and other game narrative content alongside structural features in a deference of responsibility to game engines and our own approach to mixing calligraphic and sculptural hyper- text structure

Self-assembly of mechanoplasmonic bacterial cellulose-metal nanoparticle composites

Nanocomposites of metal nanoparticles (NPs) and bacterial nanocellulose (BC) enable fabrication of soft and biocompatible materials for optical, catalytic, electronic, and biomedical applications. Current BC-NP nanocomposites are typically prepared by in situ synthesis of the NPs or electrostatic adsorption of surface functionalized NPs, which limits possibilities to control and tune NP size, shape, concentration, and surface chemistry and influences the properties and performance of the materials. Here a self-assembly strategy is described for fabrication of complex and well-defined BC-NP composites using colloidal gold and silver NPs of different sizes, shapes, and concentrations. The self-assembly process results in nanocomposites with distinct biophysical and optical properties. In addition to antibacterial materials and materials with excellent senor performance, materials with unique mechanoplasmonic properties are developed. The homogenous incorporation of plasmonic gold NPs in the BC enables extensive modulation of the optical properties by mechanical stimuli. Compression gives rise to near-field coupling between adsorbed NPs, resulting in tunable spectral variations and enhanced broadband absorption that amplify both nonlinear optical and thermoplasmonic effects and enables novel biosensing strategies

Conserved amino acids in each subunit of the heteroligomeric tRNA m1A58 Mtase from Saccharomyces cerevisiae contribute to tRNA binding

In Saccharomyces cerevisiae, a two-subunit methyltransferase (Mtase) encoded by the essential genes TRM6 and TRM61 is responsible for the formation of 1-methyladenosine, a modified nucleoside found at position 58 in tRNA that is critical for the stability of tRNAiMet. The crystal structure of the homotetrameric m1A58 tRNA Mtase from Mycobacterium tuberculosis, TrmI, has been solved and was used as a template to build a model of the yeast m1A58 tRNA Mtase heterotetramer. We altered amino acids in TRM6 and TRM61 that were predicted to be important for the stability of the heteroligomer based on this model. Yeast strains expressing trm6 and trm61 mutants exhibited growth phenotypes indicative of reduced m1A formation. In addition, recombinant mutant enzymes had reduced in vitro Mtase activity. We demonstrate that the mutations introduced do not prevent heteroligomer formation and do not disrupt binding of the cofactor S-adenosyl-l-methionine. Instead, amino acid substitutions in either Trm6p or Trm61p destroy the ability of the yeast m1A58 tRNA Mtase to bind tRNAiMet, indicating that each subunit contributes to tRNA binding and suggesting a structural alteration of the substrate-binding pocket occurs when these mutations are present