Propagating chain-free normal forms for EOL systems

We establish two types of normal forms for EOL systems. We first show that each ε-free EOL language can be generated by a propagating EOL system in which each derivation tree is chain-free. By this we mean that it contains at least one path from the root to the grandfather of a leaf in which each node has more than one son. We use this result to prove that each ε-free EOL language can be generated by a propagating EOL system in which each production has a right side of length at most two and which does not contain nonterminal chainproductions, i.e., productions A → B for nonterminals A and B. As applications of our results we give a simple proof for the decidability of the finiteness problem for EOL systems and solve an open problem concerning completeness of EOL forms

Vehicle level health assessment through integrated operational scalable prognostic reasoners

Today’s aircraft are very complex in design and need constant monitoring of the systems to establish the overall health status. Integrated Vehicle Health Management (IVHM) is a major component in a new future asset management paradigm where a conscious effort is made to shift asset maintenance from a scheduled based approach to a more proactive and predictive approach. Its goal is to maximize asset operational availability while minimising downtime and the logistics footprint through monitoring deterioration of component conditions. IVHM involves data processing which comprehensively consists of capturing data related to assets, monitoring parameters, assessing current or future health conditions through prognostics and diagnostics engine and providing recommended maintenance actions. The data driven prognostics methods usually use a large amount of data to learn the degradation pattern (nominal model) and predict the future health. Usually the data which is run-to-failure used are accelerated data produced in lab environments, which is hardly the case in real life. Therefore, the nominal model is far from the present condition of the vehicle, hence the predictions will not be very accurate. The prediction model will try to follow the nominal models which mean more errors in the prediction, this is a major drawback of the data driven techniques. This research primarily presents the two novel techniques of adaptive data driven prognostics to capture the vehicle operational scalability degradation. Secondary the degradation information has been used as a Health index and in the Vehicle Level Reasoning System (VLRS). Novel VLRS are also presented in this research study. The research described here proposes a condition adaptive prognostics reasoning along with VLRS

DNA mismatch repair and cellular response to cytarabine :implications for the pathogenesis and treatment of therapy-related acute myeloid leukaemia

PhD ThesisThe DNA mismatch repair (MMR) pathway is responsible for correction of replicative errors, hence is a key factor in maintenance of genomic stability. Paradoxically, functional DNA MMR also mediates the cytotoxicity of certain chemotherapeutic DNA damaging agents. Poor treatment response in therapy-related acute myeloid leukaemia (t-AML) is influenced by a number of factors, one of which might be chemoresistance due to acquired defects in DNA MMR. Using a range of paired MMR proficient and deficient cell lines, investigations herein demonstrate that DNA MMR status mediates response to nucleoside analogues such as cytarabine (Ara-C) used in t-AML chemotherapy. Interestingly, defects of specific MMR components had different and opposing effects on the cytotoxicity of these agents. These findings implicate defects of MMR components as potential prognostic factors in t-AML and suggest assessment of DNA MMR status may be warranted in individual patients when selecting treatment. Cytarabine was mutagenic to DNA at the TK and HPRT loci. Furthermore, the frequency of Ara-C-induced mutation was increased in an MMR-deficient cell line, supporting a role for MMR components in the cellular response to nucleoside analogues, and also suggesting that use of these agents themselves could contribute to the risk of t-AML development. Defective DNA MMR might also contribute to development of relapsed AML, given that genomic instability is demonstrated in some patients at relapse. Genome-wide analysis of DNA copy number aberrations and loss of heterozygosity in a small cohort of matched presentation and relapsed AML samples demonstrated a potential MMR defect in one patient, and also provided some important insights into the clonal origins of relapsed AML. The findings of these investigations together highlight several important considerations for the use of nucleoside analogues in the treatment of t-AML, as well as in other cancers in which dysfunction of the DNA MMR system is implicated.Leukaemia and Lymphoma Researc