This study investigates interaction in eight sibling pairs aged 1-5 years with the purpose of examining the prevalence of certain variables constituting the interaction. The siblings were observed with video camera while playing with a toy brought along by the author. In order to validate and expand upon the information obtained from the observations, the parent(s) were asked to respond to a number of questions from a Questionnaire. The variables investigated were reciprocal and complementary interaction, asymmetrical roles, imitation, conflict, joint and parallel play and communication. The results obtained indicate that, in these eight sibling pairs, reciprocal interaction, that is interaction taking place on an equal level, is signified by joint play. Complementary interaction, that is interaction taking place on different levels, is signified by parallel play. High activity level for boys versus low activity level for girls in three sibling pairs were observed to correspond to gender-specific play activities in everyday life.

<p>Species of Campylobacter, Arcobacter and Helicobacter have been associated with various diseases in humans and animals / and chickens have been identified as a reservoir of these microorganisms. Two published techniques and a new technique, developed in this dissertation, were evaluated to test its efficiency in removing PCR inhibitors from chicken samples. All of the techniques were based on agarose/DNA slants and were evaluated using multiplex PCR and an Internal Amplification Control. The new technique was found to be most effective and consequently used further in the study. A novel study was done to evaluate the survival of Campylobacter, Arcobacter and Helicobacter strains in chicken blood at -20, 4, 37 and 42&ordm / C as well as at ambient room temperature (&plusmn / 22&ordm / C). It was found that all strains could survive at all temperatures, albeit at different duration times. Most notably, an A. butzleri strain was able to survive at 4oC for up to 297 days.</p>

One of the most conspicuous features of mergers is that they come in waves that are correlated with increases in share prices and price/earnings ratios. We use a natural way to discriminate between pure stock market influences on firm decisions and other influences by examining merger patterns for both listed and unlisted firms. If "real" changes in the economy drive merger waves, as some neoclassical theories of mergers predict, both listed and unlisted firms should experience waves. We find significant differences between listed and unlisted firms as predicted by behavioral theories of merger waves. (author's abstract)

As from the beginning of the 20th century, there has been a shift in the scale of architectural production as an outcome of advanced construction technologies, new range of building materials, automation of building services and progressive infrastructural networks. The increased physical capacity -the deeper and taller buildings- not only increased the scale of the architectural practice in relation with urban planning, but also presented architecture the possibility to offer a wider social programmation for the reorganization of the urban territory. The increase in the scale of architectural production, this study would argue, has given rise to a critical tension between the fields of architecture and urbanism. The aim of this study is to understand alternative positions towards the relationship between architecture and urbanism in the production of the city through a cross-reading of the architectural-urban theories of Le Corbusier and Rem Koolhaas. At a very preliminary investigation, the urban thinking of Le Corbusier represents the modernist ideal in architecture that is after the rational and linear architectural production of the city with all its social, cultural and economic components. The theory generated by Rem Koolhaas, on the other hand, represents the end of the modernist ideal on the city, since it refuses the possibility of imposing a rigid, definitive and stable program on the city through the mediation of architecture. What separates these two positions is the turning point in the social and cultural structure that was experienced in 1960&rsquo / s, but what makes possible a continuous reading is the both architect&rsquo / s attempt to radicalize the scale of the architectural production, with diverse approaches towards its programmation. The study is an attempt to make this comparative analysis in order to understand what has changed from one to another in terms of their understanding of form, scale, program and context in architectural production, as well as their position towards social programmation of the urban organization.

Acute graft versus host disease (aGVHD) affects more than 40% of patients undergoing haematopoietic stem cell transplantation. aGVHD occurs after transplantation of donor haematopoietic cells into hosts incapable of rejecting the donor cells, when donor T cells attack host tissue. Despite extensive efforts, aGVHD remains problematic to prevent and difficult to control. Current therapies to prevent aGVHD induce profound immunosuppression, leaving patients at increased risk of infection and leukaemic relapse. Dendritic cells (DC) are professional antigen presenting cells of haematopoietic origin and are the primary stimulators of the immune system, uniquely being able to activate naïve T cells. A growing body of evidence suggests that DC are responsible for the stimulation of the donor T cells which cause aGVHD. I have used a model of aGVHD which utilizes conditioned severe combined immunodeficient mice transplanted with human peripheral blood mononuclear cells (PBMC). In this model human CD4+ T cells appear to be responsible for an aGVHD-like syndrome which results in death 15-30 days post transplant. I have shown, using in vitro depletion of individual populations, that other subpopulations of human PBMC did not affect the survival of the mice. I have also demonstrated that human DC are required for the induction of aGVHD in the majority of mice. This novel finding validated the use of this model to test the primary hypothesis; that antibody mediated depletion of DC would prevent aGVHD. The murine IgM monoclonal antibody (Mab), CMRF-44 Mab, is specific for an unknown molecule expressed on the surface of activated human DC. Previous work had shown that when mixed lymphocyte reaction stimulator cells were depleted of CMRF-44+ cells, there was a significant reduction in the proliferation of responder cells. Here I tested the efficacy of CMRF-44 as a therapy for the prevention of aGVHD in the model. CMRF-44 Mab did not improve survival of mice treated with human PBMC, despite recent data showing that CMRF-44 expression on DC was predictive of aGVHD in patients. In vitro depletion of CMRF-44+ cells from human PBMC prior to transplantation also did not reduce incidence of aGVHD. An alternate target for the depletion of human DC was CD83 which is also expressed on the surface of activated human DC. I generated a rabbit polyclonal antibody using a human CD83 fusion protein, which was then affinity purified in a multi-step process which yielded only antibody specific for human CD83. Treatment with this antibody greatly improved survival of transplanted mice. Further experiments showed that anti-CD83 treatment did not abrogate human leucocytes including CD8+ memory T cells suggesting that a therapy using an anti-CD83 antibody has the potential to prevent aGVHD without the immunosuppression associated with current anti-aGVHD therapies. The work described here has validated the use of a human mouse chimeric model as an in vivo assay of human DC function and shown that targeting CD83 has the potential to reduce the incidence of clinical aGVHD whilst preserving donor memory T cells.

Thesis (Ph. D.)--Washington State University, May 2009. / Title from PDF title page (viewed on Apr. 21, 2010). "Department of Psychology." Includes bibliographical references (p. 39-43).

Thesis (Ph. D.)--Ohio State University, 2006. / Available online via OhioLINK's ETD Center; full text release delayed at author's request until 2009 Apr 26

There is an urgent need for novel preventive and therapeutic strategies for graft versus host disease (GvHD) occurring after allogeneic hematopoietic cell transplantation (allo-HCT). T-cell-based immunotherapies have been developed, however there are still some hurdles for the use of currently availably regulatory T-cells in clinical practice (naturally occurring FOXP3 + nTregs and inducible regulatory T cells), mainly owing to the lack of specific cell surface markers. The hypomethylating agent azacytidine (5-aza-dC) has been shown to generate immunoregulatory T-cells ex vivo. Interestingly, it has been shown that genes other than FOXP3 are responsible for the suppressor function of 5-aza-dC induced T-regs. HLA-G is a surface molecule with potent immunoregulatory functions which is normally expressed during pregnancy protecting the “semi-allogeneic” fetus from maternal immune attack and then is epigenetically repressed. The aim of this study was the induction of HLA-G expression in T-lymphocytes with the use of the demethylating agent 5-Aza-dC and investigation of their possible immunoregulatory properties. Our results showed that short in vitro treatment of peripheral blood T-cells with 5-aza-dC induces HLA-G expression and, more importantly, these induced HLA-G + T-cells could suppress lymphoproliferation when added as third party cells in mixed lymphocyte cultures. This suppression seems to be reduced after HLA-G neutralization and cell-to-cell contact independent. Furthermore, these induced HLA-G + T-cells show a reduced proliferation to allogeneic stimuli. Taken together, our results indicate the ex vivo production of HLA-Gpos T-lymphocytes with immunoregulatory properties. Our long term goal is the use of this population as adoptive cellular therapy for GvHD and other T-cell mediated diseases. / -

Thesis (MEng)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Thorough layout verification of superconductor integrated circuits goes beyond design rule checking and parameter value extraction. The former is used to verify adherence to process design rules, and the latter to determine the element values of components such as inductors and resistors and Josephson junction critical currents. Still, neither gives much warning against subtle layout errors that could result in unintended parasitic elements, or a circuit that does not reflect the original circuit topology. A specialized implementation for Cadence Virtuoso allows layout-versus-schematic verification, but it is limited both to commercial software and in terms of its usefulness. Parameter extraction software such as InductEx is used to extract the component element values of a circuit from its layout if the circuit topology is provided as a netlist, which is mostly created by the designer. However, the element values are extracted for the supplied topology, even if a layout mistake such as creating a connection to the wrong node or a mistake in the netlist results in a model mismatch. After a failed verification, further diagnosis is required to determine whether the error is indeed in the layout or in the input topology - prolonging the verification process significantly. Here we present a free-standing layout-versus-schematic verification toolkit for superconductive integrated circuits, and discuss its implementation after systematically considering the algorithms at its core. We demonstrate results of the layout-versus-schematic verification and how the layout-versus-schematic toolkit is used as a whole in conjunction with InductEx to perform automated parameter extraction for cell-level layout verification. The current version of this toolkit provides the user with three stand-alone tools that are best used in conjunction with InductEx: A GDSII file flattener, a layout-to-schematic netlist extractor (with the option of viewing a pictorial reconstruction of the netlist and schematic) and a netlist comparison tool by which the user can determine whether a layout agrees with an input schematic. We conclude that the netlist comparison and viewing tool provides a valuable method for expediting the layout verification process, making it more efficient and minimizing the chances of mistakes. In its current form the layout-to schematic tool is still limited in that it cannot yet fully support circuits with mutual coupling. Although many improvements can still be made to this toolkit, the implemented version of these tools can already provide great benefit to Rapid Single Flux quantum (RSFQ) cell designers. / AFRIKAANSE OPSOMMING: Deeglike uitleg verifikasie van supergeleier geïntegreerde stroombane strek verder as bloot die nasien van ontwerpreëls en die onttrekking van parameter waardes. Eersgenoemde word gebruik om vas te stel of daar voldoen word aan die proses se ontwerpreëls, en laasgenoemde om die waardes van komponente soos induktors en resistors en die kritiese strome van Josephson aansluitings te bepaal. Nogtans bied nie een van hulle veel waarskuwing teen subtiele uitlegfoute wat onbeplande parasitiese elemente kan veroorsaak nie, of teen ‘n stroombaan wat nie die oorspronklike stroombaan topologie weerspieël nie. ‘n Gespesialiseerde implementasie van Cadence Virtuoso maak LVS (layout-versus-schematic) verifikasie moontlik, maar dit is beperk tot kommersiële sagteware en ook beperk in terme van bruikbaarheid. Parameter onttrekking sagteware soos InductEx word gebruik om waardes van die komponent-elemente van ‘n stroombaan vanuit die uitleg te onttrek wanneeer die stroombaan topologie as ‘n netlist, wat meestal deur die ontwerper geskep is, voorsien word. Die elementwaardes word egter onttrek volgens die topologie wat verskaf is, al is daar uitlegfoute, soos byvoorbeeld wanneer ‘n koppeling met ‘n verkeerde node plaasvind, of wanneer daar netlist foute is wat modelteenstrydighede veroorsaak. Na ‘n mislukte verifikasie poging word verdere diagnostiese stappe gedoen om te bepaal of die fout in die uitleg lê, of in die spesifieke topologie wat verskaf is, wat natuurlik die verifikasieproses aansienlik verleng. Hier stel ons ‘n vrystaande LVS verifikasie sagteware-pakket vir supergeleier geïntegreerde stroombane bekend, en bespreek, deur middel van die algoritmes wat die kern daarvan uitmaak, die implementering van hierdie sagteware-toestel. Ons bied die resultate van die LVS verifikasie aan en wys hoe die LVS sagteware toestel as geheel saam met InductEx gebruik kan word om automatiese parameter uittrekking vir sel-vlak uitleg verifikasie te berwerkstellig. Die huidige weergawe van die pakket bied die verbruiker drie alleenstaande programme wat verkieslik saam met InductEx gebruik moet word: ‘n GDSII “file flattener”, ‘n uitleg-tot-schematiese diagram netlist ekstraktor (met die opsie om ‘n herkonstruktueerde beeld van netlist en skematiese diagram te besigtig) en ‘n netlist vergelyking toestel waarmee die verbruiker kan vasstel of ‘n uitleg met ‘n oorspronklike skematiese diagram ooreenstem. Ons lei af dat die netlist vergelyking toestel ‘n waardevolle metode bied om die uitleg verifikasie proses te bespoedig en vergemaklik en die kanse van foute te minimaliseer. In sy huidige vorm is die uitleg-tot-skematiese diagram toestel beperk omdat dit nog nie stroombane met koppeling kan steun nie.

Cette thèse traite de l'analyse économique des conflits, et plus particulièrement de l'apport d'une méthode, la "Contest Theory". En partant du postulat simple que les agents économiques réalisent un arbitrage beurre-canons, les conflits ont pu être intégrés dans le champ de l'analyse économique. Dans le premier chapitre, nous proposons une synthèse des principaux résultats et nous décrivons le rôle décisif des Contest Success Functions dans ce cadre théorique. Le second chapitre montre que, pour traiter des conflits armés, l'identité institutionnelle des agents devrait davantage être pris en considération dans les modèles de la "Contest Theory". Le troisième chapitre s'intéresse aux motivations pouvant expliquer le commerce d'armes entre ennemis. Nous montrons que si le vendeur dispose d'une technologie militaire et non militaire plus efficace que l'acheteur, le commerce d'armes peut s'avérer mutuellement avantageux. Dans le quatrième chapitre nous proposons d'estimer et de comparer les quatre plus grandes formes de Contest Success Functions en recourant à des données provenant du monde virtuel. À partir d'un échantillon de 1957 batailles, nous trouvons que la forme ratio est celle qui a la plus grande qualité prédictive. En d'autres termes, le principal facteur expliquant la victoire sur un champ de bataille (virtuel) est le ratio du nombre de canons déployés. / This thesis deals with conflict economics, and more precisely with the contributions of the Contest Theory to the field. This method assumes that economic agents face a trade off between guns and butter's activities. By doing so, it allows the consideration of conflicts in economic mainstream. In the first chapter, we offer a survey on guns versus butter models. In particular, we focus on Contest Success Functions which are the cornerstone of the framework. The second chapter highlights one limit of the models of contest theory in conflict economics namely the lack of importance given to the identity of agents. The third chapter studies the motivation which can explain the existence of arms trade between enemies. We show that if the seller has a higher productivity both in guns and butter's activity, there exists a mutually benefficial agreement. As a result, even between enemies, arms trade may be rational. In the fourth chapter, we estimate and compare the four main forms of Contest Success Functionsusing data coming from virtual worlds. Based on a sample of 1957 (virtual) battles, we find that the ratio form is always the best-fit Contest Success Function.