Innovation and failure in mechatronics design education

Innovative engineering design always has associated with it the risk of failure, and it is the role of the design engineer to mitigate the possibilities of failure in the final system. Education should however provide a safe space for students to both innovate and to learn about and from failures. However, pressures on course designers and students can result in their adopting a conservative, and risk averse, approach to problem solving. The paper therefore considers the nature of both innovation and failure, and looks at how these might be effectively combined within mechatronics design education

Delineating neuroinflammation, parasite CNS invasion, and blood-brain barrier dysfunction in an experimental murine model of human African trypanosomiasis

Although Trypanosoma brucei spp. was first detected by Aldo Castellani in CSF samples taken from sleeping sickness patients over a century ago there is still a great deal of debate surrounding the timing, route and effects of transmigration of the parasite from the blood to the CNS. In this investigation, we have applied contrast-enhance magnetic resonance imaging (MRI) to study the effects of trypanosome infection on the blood-brain barrier (BBB) in the well-established GVR35 mouse model of sleeping sickness. In addition, we have measured the trypanosome load present in the brain using quantitative Taqman PCR and assessed the severity of the neuroinflammatory reaction at specific time points over the course of the infection. Contrast enhanced – MRI detected a significant degree of BBB impairment in mice at 14 days following trypanosome infection, which increased in a step-wise fashion as the disease progressed. Parasite DNA was present in the brain tissue on day 7 after infection. This increased significantly in quantity by day 14 post-infection and continued to rise as the infection advanced. A progressive increase in neuroinflammation was detected following trypanosome infection, reaching a significant level of severity on day 14 post-infection and rising further at later time-points. In this model stage-2 disease presents at 21 days post-infection. The combination of the three methodologies indicates that changes in the CNS become apparent prior to the onset of established stage-2 disease. This could in part account for the difficulties associated with defining specific criteria to distinguish stage-1 and stage-2 infections and highlights the need for improved staging diagnostics

Simplifying the construction of domain-specific automatic programming systems: The NASA automated software development workstation project

An overview is presented of the Automated Software Development Workstation Project, an effort to explore knowledge-based approaches to increasing software productivity. The project focuses on applying the concept of domain specific automatic programming systems (D-SAPSs) to application domains at NASA's Johnson Space Center. A version of a D-SAPS developed in Phase 1 of the project for the domain of space station momentum management is described. How problems encountered during its implementation led researchers to concentrate on simplifying the process of building and extending such systems is discussed. Researchers propose to do this by attacking three observed bottlenecks in the D-SAPS development process through the increased automation of the acquisition of programming knowledge and the use of an object oriented development methodology at all stages of the program design. How these ideas are being implemented in the Bauhaus, a prototype workstation for D-SAPS development is discussed

A learning apprentice for software parts composition

An overview of the knowledge acquisition component of the Bauhaus, a prototype computer aided software engineering (CASE) workstation for the development of domain-specific automatic programming systems (D-SAPS) is given. D-SAPS use domain knowledge in the refinement of a description of an application program into a compilable implementation. The approach to the construction of D-SAPS was to automate the process of refining a description of a program, expressed in an object-oriented domain language, into a configuration of software parts that implement the behavior of the domain objects

Nova Aquilae 1918 (V603 Aql) Faded by 0.44 mag/century from 1938-2013

We present the light curve of the old nova V603 Aql (Nova Aql 1918) from 1898-1918 and 1934-2013 using 22,721 archival magnitudes. All of our magnitudes are either in, or accurately transformed into, the Johnson $B$ and $V$ magnitude systems. This is vital because offsets in old sequences and the visual-to-$V$ transformation make for errors from 0.1-1.0 magnitude if not corrected. Our V603 Aql light curve is the first time that this has been done for any nova. Our goal was to see the evolution of the mass accretion rate on the century time scale, and to test the long-standing prediction of the Hibernation model that old novae should be fading significantly in the century after their eruption is long over. The 1918 nova eruption was completely finished by 1938 when the nova decline stopped, and when the star had faded to fainter than its pre-nova brightness of $B=11.43 \pm 0.03$ mag. We find that the nova light from 1938-2013 was significantly fading, with this being seen consistently in three independent data sets (the Sonneberg plates in $B$, the AAVSO $V$ light curve, and the non-AAVSO $V$ light curve). We find that V603 Aql is declining in brightness at an average rate of $0.44 \pm 0.04$ mag per century since 1938. This work provides remarkable confirmation of an important prediction of the Hibernation model.Comment: 13 pages, 1 figure, 2 electronic online data tables, Accepted for publication ApJLet

Synthesis and Evaluation of New Ligands for Gallium Radiolabelling

A series of N3O3 triaza-tricarboxylate hexadentate ligands, based on the 6-amino-1,4-diazepine scaffold, has been designed and synthesised. An investigation of the suitability of these ligands towards application in 68Ga-PET has been conducted, with particular focus on the efficiency and efficacy of radiolabelling. Subsequently, selectivity for Ga(III) over other relevant cations has been studied, along with exploration of the kinetics of radiolabelling, stability and in vivo behaviour of the radiolabelled complexes in healthy rats. The four best candidates quantitatively radiolabel within three minutes at room temperature over the pH range 4 – 7, to give a single 68Ga-radiolabelled species which is sufficiently stable for in vivo application. As a result, these compounds are very promising candidates for use as ligands in 68Ga-PET. Decoration of the AMPED scaffold amine functionalities yielded a series of chelators, which allowed the 68Ga-radiolabelling properties of this family of ligands to be investigated. The ligands have a mixture of acyclic and cyclic properties, which facilitated rapid binding of the metal and formation of a stable complex. Synthetic details and 1H NMR solution state properties are described. With respect to radiolabelling, the best ligands were those with the least sterically demanding exocyclic amine substituents. However, ligands featuring a mono-alkylated exocyclic amine were prone to internal lactamisation under acidic conditions, which rendered these compounds ineffectual as ligands for 68Ga. The synthesis and radiochemical evaluation of an additional series of ligands, featuring a modified core structure, designed to inhibit the lactamisation reaction and promote ‘pre-organisation’ of the ligand donors were undertaken. The synthetic methodology developed allows for selective functionalisation of the different amine groups of the ring. Modification of the AMPED core by substitution of the tertiary methyl group for a phenyl moiety increased the steric bulk close to exocyclic amine, which inhibited internal lactamisation. Critically, the methyl-for-phenyl substitution does not have a detrimental effect on the complexation properties. Finally a study was undertaken of the radiolabelled complex speciation, using NMR spectroscopy and X-ray crystallography. The presence of multiple radiolabelled complex species was attributed to the formation of kinetically trapped complexes of differing stability. The relative population of the two major ligand conformations is controlled by the relative steric demand of the substituents at the quaternary site. The exocyclic amine is subject to protonation (pKa 5.7), and therefore the relative population of the ligand conformers is pH dependent over the range 3 – 7. By substituting the methyl group for a more sterically demanding phenyl group, the population of the ligand conformation favouring fast and stable gallium binding was increased

A very different kind of rule: Credal rules, argumentation and community

In mainstream Anglo-American philosophy, the relation between cognition and community has been defined primarily in terms of the generalization of the mathematical function (Frege, Russell), especially as a model for the nature of rules (Wittgenstein and followers), which thus come to be under-stood as algorithms. This leads to the elimination of both the reflexive, synthesizing subject (for it is unnec-essary to the algorithmic decision-making procedure installed in the rule), and the intrinsic communal-historical nature of argumentation and belief-formation. Against this approach, I follow R.G. Collingwood’s hitherto unrecognized strategy in his Essay on Metaphysics (1940) and argue that the relation of cognition and community is better understood by way of the ancient and forgotten model of creedal rules of faith or trust. These will be shown to have the logical form of first person performative rules of faith or trust that generate third person declaratives or proposi-tions, and so constitute the possibility conditions for an argumentational logic of question and answer. They restore the synthetic subject, for they are not algorithms but reflexive and interpretive formulae; they are communally constituted and so historically saturated; and they reinstate an ontological theory of truth as disclosure, with coherence and comprehensiveness as its criteria. In these respects, as Collingwood saw, the creedal model provides a fresh interpretation of the historicality of argumentation and redefines the relation of cognition and community in terms of the interdependence of faith and reason