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This research was designed primarily to determine whether and to what extent several species of Dipteria (true flies) carry viable dissemules of algae and or Protozoa "in-flight."

A leading cause of male infertility is genetic variation in genes required for sperm formation and/or function. There is evidence to suggest PACRG is involved in mammalian spermatogenesis. Specifically, the loss of Pacrg function causes a spermatogenic defect and male infertility in mice. To investigate if PACRG plays a similar role in human spermatogenesis, the localisation of PACRG was determined in human testis. Using an immunohistochemical approach, this study demonstrated that PACRG is localised to the human sperm flagella. To investigate a potential role for PACRG in human male infertility, sequence analysis and an association study were performed. Sequence analysis did not identify any pathological alterations. However, 1 of 3 variants identified (rs9347683) was shown to be significantly associated with male infertility by association analysis (p=0.009, Odds Ratio=1.6, n=766). / A high degree of structural and functional conservation exists between different types of motile cilia/flagella. Evidence from studies in C.reinhardtii and T.brucei indicate Pacrg is necessary for axoneme formation and microtubule stability. To test the role of the mammalian homologue, this study characterised the Pacrg knockout mouse, quakingviable (qkv) and generated Pacrg transgenic qkv mice (qkv-Tg). Using immunohistochemistry and immunoelectron microscopy this study demonstrated that Pacrg was localised to the axonemal microtubule doublets of sperm and ependymal cilia. The absence of Pacrg was associated with compromised sperm flagella formation and male infertility. In addition, histological and MRI analysis of qkv mutant mice revealed hydrocephalus. Specifically, qkv mutant mice showed a ~2.5 fold expansion of the lateral ventricle area compared to wildtype mice. The hydrocephalus phenotype was associated with a reduction in ependymal cilial beat frequency (CBF). Transgenic expression of Pacrg was sufficient to rescue the hydrocephalus and infertility phenotypes. In conclusion, this study has demonstrated that Pacrg is a novel axonemal protein in a subset of motile cilia and loss of Pacrg function results in spermiogenic defects and hydrocephalus in mice. Further, this study has shown that variations in the human PACRG promoter are a risk factor in human male infertility. Collectively these data provide evidence for a conserved role of PACRG in the cilial axoneme. This suggests the protein may be a candidate for a variety of human diseases characterised by cilial dysfunction.

Cette thèse rappelle les fondements du pilotage des systèmes logistiques et montre l'intérêt de la mise en place d'un SCP (Systèmes Contrôlés par le Produit). L'intégration de tels systèmes doit d'abord prendre en compte la cohérence entre les différents éléments le constituant. Ainsi les systèmes centralisés cherchent à proposer des plans de moyen-long termes visant un optimal de coût, mais aussi une certaine stabilité et peu de nervosité dans le temps. Par ailleurs, les systèmes distribués ont démontré leur capacité à permettre une réaction rapide à des événements impromptus survenant dans le système physique. L'hybridation de ces deux types de pilotage est donc une voie de gain de productivité pour les systèmes logistiques et industriels. Le premier chapitre de la thèse décrit l'évolution des systèmes de planification et de pilotage de la production, avec l'objectif d'identifier les forces et faiblesses des différentes approches proposées jusqu'à nos jours et permettent définir l'objectif général de la thèse. Le chapitre deux analyse l'état de l'art concernant les outils de modélisation des systèmes de production centralisés/distribués et aussi le concept de contrôle par le produit. Ce chapitre sert de base pour définir les objectifs spécifiques de la thèse. Le chapitre trois présente le cadre de modélisation proposé. Ce cadre est basé sur une approche cybernétique, et plus spécifiquement sur le modèle de système viable (VSM). Le chapitre démarre avec une présentation générale du modèle de système viable, puis présente un modèle générique de modélisation de systèmes contrôlés par le produit. Enfin, le chapitre décrit une application de ce cadre général aux systèmes de planification et pilotage de la production de type SCP. Le chapitre quatre définit les différentes méthodes de décision, tant centralisées que distribuées, développées pour l'implémentation du modèle générique définit dans le chapitre trois. Aux niveaux centralisés et distribués ces méthodes sont basées sur des modèles de programmation mathématique développés pour considérer l'adaptabilité et la flexibilité du système. Le chapitre cinq montre les principaux résultats dans une application basée sur un cas industriel qui a nécessité le développement d'un outil de simulation qui considère des variables de court, moyen et long termes pour les différents modèles d'optimisation. Ces résultats montrent l'intérêt de ce type d'hybridation / This thesis is concerned with the foundations of the planning and control logistics systems and shows the interest of the PDS (Product-driven Systems) applied in this context. The development of such systems must consider the coherence between the different components. Centralized systems offer long terms plans aiming an optimal cost, but also some stability and nervousness reduction. Distributed systems allow a fast reaction to perturbations happening in the physical system. Then, the hybridization of these two kinds of planning and control systems is a way of increase productivity for logistic and industrial systems. The first chapter of the thesis describes the evolution of the production planning and control systems, to identify forces and weaknesses of the different approaches proposed until our days and allow to define the general objective of the thesis. Chapter two analyses the state of the art concerning the tools for modeling hybrid centralized/distributed production systems and also the concept of product-driven systems. This chapter serves as a basis to define the specific objectives of the thesis. Chapter three introduces the proposed modeling framework. This framework is based on a cybernetic approach, and more specifically in the Viable System Model (VSM). The chapter starts with a general presentation of VSM and then introduces a generic framework to model PDS. Finally, this chapter describes an application for production planning and control. Chapter four defines the different decision methods developed for the implementation of the generic model defined in the chapter three. At centralized and distributed levels these methods are based on mathematical programming models. Chapter five shows the main results of an application based on an industrial case which required the development of a simulation tool which considers variables of short, médium and long terms for the different optimization models. These results show the interest of this type of hybridization

En säker bakteriediagnostik kräver en korrekt provtagningsteknik, ett lämpligt transportsätt och rätt odlingsteknik. På grund av centralisering av verksamheter och ekonomiska begräsningar, är transport av prover till mikrobiologilaboratorium mycket vanligt. Detta medför behov av ett transportmedium som håller känsliga bakterier vid liv under långa transport- och förvaringstider. Dessutom skall transportrören klara av maskinell utodling som kräver ett vätskebaserat provtagningsmedium. Denna övergång minskar även arbetsbelastning och förbättra ergonomin hos personalen. I denna studie utvärderades viabilitet av Propionibacterium acnes (n=3), Bacteroides fragilis (n=2) och Neisseria gonorrhoeae (n=3) i transportmediet från COPAN E-swab™. Alla tre bakterier förvarades i transportrören i 24, 48 och 72 timmar (h) och dessutom i 120h för P. acnes och B. fragilis. Den ursprungliga koncentrationen samt den procentuella viabilitetsförlusten över tid beräknades med hjälp av viable count. Efter 120h förvaring i transportmediet hade viabiliteten minskat till 47 – 80 % för P. acnes, 18 % för B. fragilis 1 och 73 % för B. fragilis 2. N. gonorrhoeae visade en minskad viabilitet med 96 – 99,97 % efter 24h förvaring i 4°C och rumstemperatur. P. acnes och B. fragilis kunde förvaras i transportmediet i upp till 5 dygn utan att diagnostiken äventyrades. N. gonorrhoeae kunde förvaras i transportmediet i 24h för att diagnostik genom odling ska vara möjlig. / Safe bacterial diagnostics requires proper sampling techniques, suitable specimen transport and correct inoculation techniques. As a result of centralization of operations and economic restraints, transportation of samples to microbiology laboratories is very common. This entails the need for a transport medium that keeps sensitive bacteria alive under the long transport and storage time. Additionally, the transport tube should be convenient for automatic inoculation that requires a liquid based medium. This transition also reduces workload and improves ergonomics of the staff. In this study the survival of Propionibacterium acnes (n = 3), Bacteroides fragilis (n = 2) and Neisseria gonorrheae (n = 3) in the transport medium Copan E-swab™   was evaluated. All the species were inoculated in the tubes for 24, 48, 72h and also 120h for B. fragilis and P. acnes.  Initial concentration at start time and the percentage survival over time was calculated with the help of viable count. Viability decreased to 47 – 80 % for P. acnes, 18 % for B. fragilis 1 and 73% for B. fragilis 2 after 120 h storage in the transportmedium. N. gonorrhoeae showed a reduction in viability of 96 – 99,97 % after 24h storage in the medium at 4°C and in room temperature. P. acnes and B. fragilis can be stored in the medium for up to 5 days, without endangering a diagnosis. N. gonorrhoeae can be stored in the transport medium for up to 24h to secure a diagnosis through culturing.

The desire to develop a holistic framework for knowing and modelling in human enterprises is not new. Methodologies, such as Systems Dynamics, Soft Systems and the Viable Systems Model all claim a holistic perspective. Each of these approaches emphasises the interrelatedness of `things', rather than the `things' themselves. Thus, they avoid the possible fragmentation that can occur when elements within a situation are treated as if they exist independently. Unfortunately, the systems approaches flounder because they fail to reconcile knowledge with the path that brings it into being, or to satisfactorily deal with the concepts of order or communication in language. The Thesis, therefore, provides a greater clarification of these issues, in the light of enactive cognitive science, chaos theory and contemporary theories on dialogue. As a result, a new framework is presented, for knowing and modelling in human enterprises, that is based on our `new' understanding of holism. The organisational context of the Thesis is provided by two generic models, both developed by the author (a model of Duopoly Competition and a model of Chaos Control ), together with a case study of the Danish hearing aid manufacturer Oticon. The Thesis concludes by presenting various insights arising from our new frame of reference and reflecting on their challenges for organisations.

This thesis investigates how individual student nurses construct a body of knowledge that is appropriate and able to support or underpin their practical experiences in the early part of their undergraduate pre-registration nursing programme. It is an exploration of how contemporary nursing students link theory, that is fit for purpose, with the art and skills that are pre-requisite for competent nursing practice. The study is written from the perspective of a senior academic and perceived gatekeeper of professional nursing standards, and uses personal and professional writing to illustrate the ontological stance adopted. Working with the core concepts introduced by Bernstein (1975), Von Glasersfeld (1989), Mezirow et al (2000) inter alia, an emergent research methodology is employed. A questionnaire is used to confirm that the Higher Education Institution where the research was conducted was typical in the UK at the time; web logs (blogs) are used to explore the individual experiences of ten student nurses; and this is supplemented by interviews, naturally occurring and other data to illuminate, extend and contextualise the findings. The findings underpin the construction of a recursive model that links heads, hands and hearts with a central focus on viable knowledge, this being the knowledge that guides practice. The contribution of this study to practice relates to the recognition that knowledge must be presented and transmitted in a viable fashion with practice being maintained as pivotal to the educational process, and the recommendations of the study for curriculum design and delivery reflect this. The research concludes that viable knowledge that is dependent upon the centrality of practice in nurse education should become the defining attribute of the nurse of the future.

Vibrio parahaemolyticus is a food-borne pathogen commonly associated with the consumption of raw or undercooked seafood resulting in primary infections of the human gastrointestinal tract. It is estimated to cause about 4500 illnesses each year in the United States. However, infection from this food-borne pathogen can be avoided if this organism is detected in the implicated food, prior to consumption. Current standard methods of detecting this organism are dependent on the culturability of the bacteria. Detection based on an organism’s culturability may be problematic as V. parahaemolyticus has been known to exist in a viable but nonculturable (VBNC) state. Bacteria in the VBNC state are characterized by low levels of metabolic activity and the inability to be cultured by standard laboratory practices. When bacteria enter the VBNC state, their gene expression profile may be different than the culturable counterpart. We were interested in comparing the expression of two virulence-associated genes between VBNC and culturable cells of V. parahaemolyticus. V. parahaemolyticus RIMD2210633 was incubated at 4°C in modified Morita mineral salt solution supplemented with 0.5% NaCl (MMS) or trypticase soy broth supplemented with 2% NaCl (TSBS), which represented nutrient poor and rich conditions, respectively. The number of VBNC and culturable cells were determined by standard plate count and fluorescence microscopy. The expression levels of virulence-associated genes tdh2 and escU, were measured relative to the housekeeping gene, pvsA, by qRT-PCR. Nutrient availability and temperatures exerted variable effects on the virulence gene expression. It is possible that VBNC V. parahaemolyticus cells may retain their pathogenicity potential.

Conversion of <i>Campylobacter upsaliensis</i> to the nonculturable but viable coccoid form was characterized. Chloramphenicol did not prevent the conversion. Severe decreases in isocitrate dehydrogenase activity and oxygen uptake and extensive degradation of ribosomal RNA suggest that the coccoid form is a degenerative form rather than part of a life cycle. The autolysins of spiral and coccoid forms of <i>C. upsaliensis</i> were also studied. Autolytic activity in the soluble and sediment fractions of sonicates of the spiral and the coccoid form of <i>C. upsaliensis</i> could not be demonstrated by native (nondenaturing) PAGE. Autolysins were detected, however, by using denaturing SDS-PAGE gels containing either purified <i>E. coli </i> peptidoglycan or whole cells of <i>Micrococcus luteus</i> as the turbid substrate, with subsequent renaturation by treatment with Triton X-100 buffer. In renaturing gels that contained <i>E. coli</i> peptidoglycan, 14 autolytic bands were detected ranging from 200 kDa to 12 kDa. In similar gels containing whole cells of <i>M. luteus</i> , only a single band appeared having a molecular weight of 34 kDa. This band corresponded to one of the bands present in the gels containing <i>E. coli </i> peptidoglycan. This common autolysin was isolated by adsorbing it from <i>C. upsaliensis</i> lysates onto <i>M. luteus</i> cells and then subjecting these cells to renaturing SDS-PAGE in gels containing <i>E. coli</i> peptidoglycan. The 34 kDa autolysin differed from a single 51 kDa autolysin unique to the <i>M. luteus cells</i>. The 34 kDa autolysin was isolated from an SDS-PAGE gel and was pure when tested by isoelectric focusing. The N-terminal amino acid sequence analysis showed the first 15 amino acids of the 34 kDa autolysin to have 67% identity with a part of antigenic protein PEB4 of <i>Campylobacter jejuni</i>. The purified autolysin was used to immunize rabbits and the antibodies produced precipitated autolytic activity from cell lysates. The specificity of the antibodies was shown by Western blotting: only a single specific band occurred, with a molecular weight of 34 kDa, and thus it seems unlikely that the 34 kDa autolysin was derived from any of the other autolysins that were detected. / Ph. D.

Following active growth, the aquatic gram-negative rod Prolinoborus fasciculus (Aquaspirillum fasciculus) exhibited a mass conversion from its culturable rod form to a nonculturable coccoid form. Chloramphenicol did not prevent the conversion. Attempts to obtain variants that would not convert to the coccoid form were unsuccessful. Although the coccoid form fluoresced with acridine orange, agarose gel electrophoresis revealed extensive ribosomal RNA degradation. Poly-Ã -hydroxybutyrate, abundant in the vegetative rods, was not detectable in the coccoid cells. The results suggest that the coccoid form of A. fasciculus is a degenerative form rather than part of a life cycle. / Master of Science