From capability to concept : fusion of systems analysis techniques for derivation of future soldier systems

The intent of this thesis is to define a set of processes for use within UK Government dismounted soldier systems research that will provide stakeholders with auditable and traceable information to understand gaps in military capability and justify future procurement decisions. The need for this approach is linked to organisational shifts within the UK Ministry of Defence, and more specifically Government research with the move towards procurement of capability rather than equipment. In conjunction with reducing defence budgets and increased scrutiny, there is a need to prioritise spending to those areas that will provide the most significant enhancement to operational effectiveness. The proposed process suite provides underpinning data to support Government decisions, from definition of military need through to concept design and prioritisation of future research activities. The approach is grounded in the field of systems thinking and systems engineering providing the logical and systematic constructs required for highly complex systems where the human is a central focus. A novel fusion of existing systems tools and techniques enables both subjective data from domain experts and objective data in the form of operational analysis and field trials to be utilised for analysis across the five NATO capability domains, with output defining the relative importance of survivability, sustainability, mobility, lethality and C4I in the context of operational and strategic level military goals as well as wider challenges represented by the doctrinal defence lines of development. Future developments should include alignment with developing pan-MoD initiatives in the form of MODAF, if required by the customer organisation. This would enable generic versions of the process suite to be applied to any defence domain and problem.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

EXPRESS: Differential IL-1 signalling induced by BMPR2 deficiency drives pulmonary vascular remodelling

Background: Bone morphogenetic protein receptor type 2 (BMPR2) mutations are present in patients with heritable and idiopathic pulmonary arterial hypertension (PAH). Circulating levels of Interleukin-1 (IL-1) are raised in patients and animal models. Whether interplay between BMP and IL- 1 signalling can explain the local manifestation of PAH in the lung remains unclear. Methods: Cell culture, siRNA and mRNA microarray analysis of RNA isolated from human Pulmonary artery (PASMC) and Aortic (AoSMC) smooth muscle cells were used. R899X+/- BMPR2 transgenic mice fed western diet for six weeks were given daily injections of IL-1ß prior to assessment for PAH and tissue collection. Results: PASMC have reduced inflammatory activation in response to IL-1ß compared with AoSMCs, however PASMC with reduced BMPR2 demonstrated an exaggerated response. Mice treated with IL-1ß had higher white blood cell counts, and significantly raised serum protein levels of IL-6 and OPG plasma levels recapitulating in vitro data. Phenotypically, IL-1ß treated mice demonstrated increased pulmonary vascular remodelling. Conclusions: IL-1ß induces an exaggerated pulmonary artery specific transcriptomic inflammatory response when BMPR2 signalling is reduced

Epigenetic Dysregulation of the Drp1 Binding Partners MiD49 and MiD51 Increases Mitotic Mitochondrial Fission and Promotes Pulmonary Arterial Hypertension: Mechanistic and Therapeutic Implications

Background -Mitotic fission is increased in pulmonary arterial hypertension (PAH), a hyperproliferative, apoptosis-resistant disease. The fission mediator, dynamin related protein 1 (Drp1) must complex with adaptor proteins to cause fission. Drp1-induced fission has been therapeutically targeted in experimental PAH. Here we examine the role of two recently discovered, poorly understood, Drp1 adapter proteins, mitochondrial dynamics protein of 49 and 51 kDa (MiD49 and MiD51) in normal vascular cells and explore their dysregulation in PAH. Methods -Immunoblots of pulmonary artery smooth muscle cells (PASMC, control, n=6; PAH, n=8) and immunohistochemistry of lung sections (control, n=6; PAH, n=6) were used to assess the expression of MiD49 and MiD51. The effects of manipulating MiDs on cell proliferation, cell cycle, and apoptosis were assessed in human and rodent PAH PASMC using flow cytometry. Mitochondrial fission was studied by confocal imaging. A microRNA (miR) involved in the regulation of MiD expression was identified using microarray techniques andin silicoanalyses. The expression of circulatory miR was assessed using qRT-PCR in healthy volunteers (HV) vs PAH patients from Sheffield, UK (plasma, HV, n=29, PAH, n=27; whole blood, HV, n=11, PAH, n=14), and then confirmed in a cohort from Beijing, China (plasma, HV, n=19, PAH, n=36; whole blood, HV, n=20, PAH, n=39). This work was replicated in monocrotaline and SU5416-hypoxia, preclinical PAH models. siRNA targeting MiDs or a miR mimic were nebulized to rats with monocrotaline-induced PAH (n=4-10). Results -MiD expression is increased in PAH PASMC, which accelerates Drp1-mediated mitotic fission, increases cell proliferation and decreases apoptosis. Silencing MiDs (but not other Drp1 binding partners, Fis1 or MFF) promotes mitochondrial fusion and causes G1-phase cell cycle arrest, through ERK1/2 and CDK4-dependent mechanism. Augmenting MiDs in normal cells causes fission and recapitulates the PAH phenotype. MiD upregulation results from decreased miR-34a-3p expression. Circulatory miR-34a-3p expression is decreased in both PAH patients and in preclinical models of PAH. Silencing MiDs or augmenting miR-34a-3p regresses experimental PAH. Conclusions -In health, MiDs regulate Drp1-mediated fission whilst in disease, epigenetic upregulation of MiDs increases mitotic fission, which drives pathologic proliferation and apoptosis resistance. The miR-34a-3p-MiD pathway offers new therapeutic targets for PAH

VAMP4 directs synaptic vesicles to a pool that selectively maintains asynchronous neurotransmission

Synaptic vesicles in the brain harbor several soluble N-ethylmaleimide-sensitive-factor attachment protein receptor (SNARE) proteins. With the exception of synaptobrevin2, or VAMP2 (syb2), which is directly involved in vesicle fusion, the role of these SNAREs in neurotransmission is unclear. Here we show that in mice syb2 drives rapid Ca2+-dependent synchronous neurotransmission, whereas the structurally homologous SNARE protein VAMP4 selectively maintains bulk Ca2+-dependent asynchronous release. At inhibitory nerve terminals, up- or downregulation of VAMP4 causes a correlated change in asynchronous release. Biochemically, VAMP4 forms a stable complex with SNAREs syntaxin-1 and SNAP-25 that does not interact with complexins or synaptotagmin-1, proteins essential for synchronous neurotransmission. Optical imaging of individual synapses indicates that trafficking of VAMP4 and syb2 show minimal overlap. Taken together, these findings suggest that VAMP4 and syb2 diverge functionally, traffic independently and support distinct forms of neurotransmission. These results provide molecular insight into how synapses diversify their release properties by taking advantage of distinct synaptic vesicle–associated SNAREs