Type IV secretion systems have been identified in several human pathogens including Bordetella pertussis, Helicobacter pylori, and Legionella pneumophila. These systems are responsible for the translocation of virulence proteins and/or DNA, thereby playing an important role in the pathogenesis of infection and plasticity of genomes. Burkholderia cenocepacia is an important opportunistic human pathogen, particularly in persons with cystic fibrosis (CF). Respiratory tract infection by B. cenocepacia in CF patients is often associated with a decline in respiratory function, and can result in acute systemic infection. Burkholderia cenocepacia strain K56-2 is part of the epidemic and clinically problematic ET12 lineage. Two type IV secretion systems have been identified in this strain; one system is plasmid encoded (designated the Ptw type IV secretion system) whereas the other is chromosomally encoded (designated the VirB/D type IV secretion system) and shows homology to the Agrobacterium tumefaciens VirB/D4 type IV secretion system. It was determined that the plasmid encoded Ptw system is a chimeric type IV secretion system composed of VirB/D4-like elements and F-specific subunits. More recently, it was found that this system translocates a protein effector (PtwE1) that is cytotoxic to plant cells. It was also determined that the positively charged C-terminal region of PtwE1 is important for translocation via the Ptw type IV secretion system. Strains of the epidemic B. cenocepacia PHDC lineage contain only a chromosomal VirB/D4-like type IV secretion system (designated BcVirB/D); and a putative effector protein associated with this system has been identified that has C-terminal transport signal and sequences different from the effectors of the Ptw type IV secretion system. It has also been shown that a competing plasmid substrate and a plasmid fertility inhibition factor act to render B. cenocepacia of the PHDC lineage incapable of expressing a plant phenotype. Thus, three type IV secretion systems have been identified in epidemic B. cenocepacia lineages. From two of these, an effector has been identified that has cytotoxic effects on eukaryotic cells, and at least one of these type IV secretion systems is able to translocate DNA substrates.

Generation IV (Gen IV) is a developing new generation of nuclear power reactors which is foreseen to bring about a safer and more sustainable production of nuclear power. A Swedish research program called GENIUS aims at developing the Gen IV technology, with emphasis on lead-cooled fast reactors. The present work is part of the GENIUS project, and deals with safeguards aspects for an envisioned future 100 MW Gen IV demonstration facility including storage and reprocessing plant. Also, the safeguards licensing aspects for the facilities have been investigated and results thereof are presented. As a basis for the study, the changed usage and handling of nuclear fuel, as compared to that of today, have been examined in order to determine how today's safeguards measures can be modified and extended to meet the needs of the demonstration facility. Safeguards approaches have been considered for within and between each unit at the demonstration facility, with the main focus on system aspects rather than proposing safeguards instrumentation on a detailed level. The proposed safeguards approach include the implementation of well-tried measures that are used at currently existing nuclear facilities as well as suggestions for new procedures. The former include, among others, regular inventory verifications, containment and surveillance measures as well as non-destructive and destructive measurements of nuclear materials. The traditional approaches may be improved and supplemented by modern techniques and approaches such as nuclear forensics, safeguards-by-design and improved on-line monitoring of streams of nuclear material. The safeguards approach for the demonstration facility should be outlined early in the licensing process, such that the facility units can be designed in a way that allows for implementation of adequate safeguards measures with minimal intrusion on the regular activities. For operating a nuclear facility in Sweden, two separate permits are required. A license application for a new facility shall be handed both to the Swedish Radiation Safety Authority and to the environmental court, which in parallel prepare for decisions according to the Nuclear Activities Act and the Environmental Code, respectively. In terms of the Swedish legislation, there are no fundamental differences between Gen IV facilities and currently existing plants. However, comprehensive investigations and evaluations would be required in order to license new Gen IV facilities.

Denna uppsats har skrivits i syfte att undersöka om finansiella aktörers information angående risk i fondsparande är förenlig med investerares riskuppfattning. Idag följer finansiella institutioner EU-direktiv och svensk lagstiftning när de riskklassificerar sina fonder. Konkret används 5-årig historisk volatilitet mätt med standardavvikelse. Vi har därför ämnat undersöka om det riskmått och teorierna som ligger till grund för det är tillfredställande i sin nuvarande form. Vi har undersökt detta med hjälp av så väl traditionell som behovsfokuserad finansieringsteori. Genomförandet har gjorts med hjälp av en enkätundersökning som skickats ut till ett urval av medlemmar i Sveriges Aktiesparares riksförbund. Vi har i och med detta urval undersökt en investerare som är något mer kunnig än en småsparare. Resultaten av undersökningen visar på att det finns en brist i kommunikationen mellan finansiella institut och investerare. Likheten mellan de begrepp som idag används och de som reflekterar investeras riskuppfattning är visserligen inte helt olika. Dock visar undersökningen på att det trots detta finns ett antal problem. För det första finns svagheter i förståelse för de akademiska begrepp som förklarar de definitioner som används hos de finansiella instituten. För det andra har investerare en mycket bredare riskdefinition än vad som förmedlas genom nuvarande praxis. Resultaten visar också på problematiken med de psykologiska aspekter som påverkar mänskligt beteende. I fondinformationens nuvarande form tas detta inte i beaktning vilket leder till en asymmetri mellan teori och verklighet. Undersökningen pekar därför på att de riskmått och teorier som ligger till grund för information om risk i fondsparande idag ej är tillräcklig. Slutsatsen är därför att det behövs förbättring från den finansiella sfären för att uppnå bättre kundkommunikation, kundskydd och konkurrenskraft.

Type IV secretion systems have been identified in several human pathogens including Bordetella pertussis, Helicobacter pylori, and Legionella pneumophila. These systems are responsible for the translocation of virulence proteins and/or DNA, thereby playing an important role in the pathogenesis of infection and plasticity of genomes. Burkholderia cenocepacia is an important opportunistic human pathogen, particularly in persons with cystic fibrosis (CF). Respiratory tract infection by B. cenocepacia in CF patients is often associated with a decline in respiratory function, and can result in acute systemic infection. Burkholderia cenocepacia strain K56-2 is part of the epidemic and clinically problematic ET12 lineage. Two type IV secretion systems have been identified in this strain; one system is plasmid encoded (designated the Ptw type IV secretion system) whereas the other is chromosomally encoded (designated the VirB/D type IV secretion system) and shows homology to the Agrobacterium tumefaciens VirB/D4 type IV secretion system. It was determined that the plasmid encoded Ptw system is a chimeric type IV secretion system composed of VirB/D4-like elements and F-specific subunits. More recently, it was found that this system translocates a protein effector (PtwE1) that is cytotoxic to plant cells. It was also determined that the positively charged C-terminal region of PtwE1 is important for translocation via the Ptw type IV secretion system. Strains of the epidemic B. cenocepacia PHDC lineage contain only a chromosomal VirB/D4-like type IV secretion system (designated BcVirB/D); and a putative effector protein associated with this system has been identified that has C-terminal transport signal and sequences different from the effectors of the Ptw type IV secretion system. It has also been shown that a competing plasmid substrate and a plasmid fertility inhibition factor act to render B. cenocepacia of the PHDC lineage incapable of expressing a plant phenotype. Thus, three type IV secretion systems have been identified in epidemic B. cenocepacia lineages. From two of these, an effector has been identified that has cytotoxic effects on eukaryotic cells, and at least one of these type IV secretion systems is able to translocate DNA substrates.

Protein oligomerization provides a way for cells to modulate function in vivo. In this study, self-assembling protein fragments from ParC, DnaX, and proteins of unknown function were used to generate phenotypes in a dominant negative manner. These fragments were expressed as Thioredoxin (TRX) fusions under the control of the inducible araBAD promoter. Fragments chosen contain only the oligomerization domain of the protein, lacking the regions necessary for catalytic function. Fragments of ParC, a subunit of Topoisomerase (Topo) IV, generated fragment-specific phenotypes. Regions that expressed both the oligomerization domain and CTD of ParC (ParC206-752 and ParC332-752) yielded filamentous cells with several different nucleoid segregation phenotypes. Another ParC fragment containing only the oligomerization domain of ParC (ranging from 333-485) yields a recA-dependent septation defect in a subset of the population. This phenotype suggests that Topo IV may be inhibiting chromosome dimer resolution. The overexpression of DnaX247-455, a fragment containing regions of both the tau and gamma subunits of the DNA Polymerase III holoenzyme, led to a severe plating defect. Upon further investigation, this fragment caused filamentation, a nucleoid defect, and induction of sulA, similar to the effects seen with the dnaX temperature-sensitive alleles. The overexpression of the various y-protein fragments yielded a variety of mediaspecific plating defects on over 50% of the proteins tested. The overexpression of the protein fragments yielded effects that were not seen by other overexpression or deletion experiments, even under similar growth conditions. The results presented here show that the overexpression of self-assembling fragments yield a variety of dominant negative phenotypes. Reducing the activity of protein complexes allows for new aspects of the physiological process to be investigated.

This research study is aimed at assisting the Texas Department of Transportation (TxDOT) in making a transition from the use of the AASHTO Standard Specifications for Highway Bridges to the AASHTO LRFD Bridge Design Specifications for the design of prestressed concrete bridges. It was identified that Type C and AASHTO Type IV are among the most common girder types used by TxDOT for prestressed concrete bridges. This study is specific to these two types of bridges. Guidelines are provided to tailor TxDOT's design practices to meet the requirements of the LRFD Specifications. Detailed design examples for an AASHTO Type IV girder using both the AASHTO Standard Specifications and AASHTO LRFD Specifications are developed and compared. These examples will serve as a reference for TxDOT bridge design engineers. A parametric study for AASHTO Type IV and Type C girders is conducted using span length, girder spacing, and strand diameter as the major parameters that are varied. Based on the results obtained from the parametric study, two critical areas are identified where significant changes in design results are observed when comparing Standard and LRFD designs. The critical areas are the transverse shear requirements and interface shear requirements, and these are further investigated. The interface shear reinforcement requirements are observed to increase significantly when the LRFD Specifications are used for design. New provisions for interface shear design that have been proposed to be included in the LRFD Specifications in 2007 were evaluated. It was observed that the proposed interface shear provisions will significantly reduce the difference between the interface shear reinforcement requirements for corresponding Standard and LRFD designs.The transverse shear reinforcement requirements are found to be varying marginally in some cases and significantly in most of the cases when comparing LRFD designs to Standard designs. The variation in the transverse shear reinforcement requirement is attributed to differences in the shear models used in the two specifications. The LRFD Specifications use a variable truss analogy based on the Modified Compression Field Theory (MCFT). The Standard Specifications use a constant 45-degree truss analogy method for its shear design provisions. The two methodologies are compared and major differences are noted.

Tidigare forskning har visat att individer uppväxta i Japan presterar bättre än individer uppväxta i USA på test avsedda att mäta spatial förmåga. En hypotes till varför har varit att en intensiv exponering för och kunskap om bildmässigt komplicerade skrifttecken (Kanji), skapar gynnsamma förutsättningar för prestationer på test av spatial förmåga. Föreliggande studie undersökte om det fanns ytterligare kognitiva domäner där Kanjikunskap kunde vara av fördel. Universitetsstudenter från Japan (n=14) med Kanjikunskap (KK) och universitetsstudenter från Sverige (n=14) utan Kanjikunskap (UKK) testades med Symbolletning från WAIS-IV för att jämföra gruppernas prestationer. Studenterna från Japan (KK) presterade signifikant högre på Symbolletning än studenterna från Sverige (UKK). Eventuell påverkan av KK samt andra faktorer som kan ha bidragit till skillnad i prestationer mellan studentgrupperna diskuteras.

The aim for this study is to investigate how the cooperation between teachers from nine-years compulsory school and comprehensive upper secondary school is organized in a Swedish municipality, based on the formulation in the Swedish curriculum. My idea is to see how the cooperation is organized, when it comes to information about pupils who haven’t passed the qualifications to upper secondary school, especially in Mathematics. Lennart Lundquist’s basic ideas about the qualities of the one who is guided, in this case the teacher, underlie my study when it comes to the directions from the school board. I carried out my study in a Swedish municipality, where I interviewed teachers at two different compulsory schools and one upper secondary school. I also let the school board become a part of my study, as they received a minor questionnaire. The results of my study points out that there is much to be done when it comes to cooperation between the teachers from different school levels. The interviewed teachers points out that they lack knowledge about each other and they ask for more physical meetings to start cooperation. The school board also seems to be aware about the lack of cooperation. One of the principals states in his questionnaire that a first physical meeting is planned this August, as a first step to generate a more organized cooperation between the school levels. At the end of this essay I also suggest how this first meeting could be a start at a new form of cooperation in the investigated municipality, for example a wider discussion between the school board and the teachers and subject-focused collegial meetings across the school levels.

The effects of global warming raise demands for reduced CO2 emissions, whereas at the same time the world’s need for energy increases. With the aim to resolve some of the difficulties facing today’s nuclear power, striving for safety, sustainability and waste minimization, a new generation of nuclear energy systems is being pursued: Generation IV. New reactor concepts and new nuclear facilities should be at least as resistant to diversion of nuclear material for weapons production, as were the previous ones. However, the emerging generation of nuclear power will give rise to new challenges to the international safeguards community, due to new and increased flows of nuclear material in the nuclear fuel cycle. Before a wide implementation of Generation IV nuclear power facilities takes place, there lies still an opportunity to formulate safeguards requirements for the next generation of nuclear energy systems. In this context, this thesis constitutes one contribution to the global efforts to make future nuclear energy systems increasingly resistant to nuclear material diversion attempts. This thesis comprises three papers, all of which concern safeguards and proliferation resistance in Generation IV nuclear energy systems and especially recycling facilities: In Paper I, proliferation resistances of three fuel cycles, comprising different reprocessing techniques, are investigated. The results highlight the importance of making group actinide extraction techniques commercial, due to the inherently less vulnerable isotopic and radiological properties of the materials in such processes. Paper II covers the schematic design and safeguards instrumentation of a Generation IV recycling facility. The identification of the safeguards needs of planned facilities can act as a guide towards the development of new instrumentation suitable for Generation IV nuclear energy systems. Finally, Paper III describes a mode of procedure for assessing proliferation resistance of a recycling facility for fast reactor fuel. The assessments may be used, as in this case, as an aid to maintain or increase the inherent proliferation resistance when performing facility design changes and upgrades.

No description available.