A Study of Optical Observing Techniques for Extra-Galactic Supernova Remnants: Case of NGC 300

We present the results of a study of observational and identification techniques used for surveys and spectroscopy of candidate supernova remnants (SNRs) in the Sculptor Group galaxy NGC 300. The goal of this study was to investigate the reliability of using [Sii]/Halpha > 0.4 in optical SNR surveys and spectra as an identifying feature of extra-galactic SNRs (egSNRs) and also to investigate the effectiveness of the observing techniques (which are hampered by seeing conditions and telescope pointing errors) using this criterion in egSNR surveys and spectrographs. This study is based on original observations of these objects and archival data obtained from the Hubble Space Telescope which contained images of some of the candidate SNRs in NGC 300. We found that the reliability of spectral techniques may be questionable and very high-resolution images may be needed to confirm a valid identification of some egSNRs.Comment: 27 Figures, 10 table

Diffractive method of measuring erythrocytes

Awarded the Gunning Victoria Jubilee Prize in Physiolog

Insulin hypoglycaemia in the treatment of the psychoses

(1). An historical introduction to the treatment of insanity is outlined. The development of the hypoglycaemic treatment is traced. (2). The case material reviewed in this thesis consist of 46 patients. Case summaries are included and are divided into two groups - Group I treated by Dr Strecker, and Group II treated by the writer. Of these, 40 were diagnosed as suffering from schizophrenia. (3). An account of the treatment is given in detail. The symptomatology is described at length, particular reference being made to the definition of coma. An account is given of the blood sugar changes, together with a t able. A relationship between coma and blood sugar was found, namely, that for coma to be produced a mean fall of 80% was necessary and. that the more rapid the fall the deeper the coma. The onset of coma seemed to coincide with an acceleration of the pulse and a raised blood, pressure. This is recorded graphically. (4). The management of hypoglycaemia has been d.iscusse and certain points in technique have been emphasised. The difficulties and dangers have been enumerated, and their prophylaxis and treat ment discussed. These undesirable phenomena are rare and usually avoidable. (5). The effects of hypoglycaemia upon the individual have been reviewed. It is considered that there is ample physiological foundation for this treatment in schizophrenia. The mental effects have been considered. Periods of lucidity are discussed and related to the fugue states of diabetics. The undoubted sedative effect of treatment in many cases is made clear. (6). Three types of remission are defined - complete, incomplete and partial. Two Tables of results are given. (7). In the evaluation of results the two groups of cases are dealt with separately. The poor results in Group I are attributed to the unsatisfactory case material, and to the inadequa treatment in many of them. It is considered that the results of treatment in Group II. though perhaps not so satisfactory as might half been hoped, are undoubtedly better than in spontaneous remissions. (8). Insulin treatment is looked upon, not as a method of treatment in itself, but as an important psycho-biological factor which, used in conjunction with other methods of treatment such a psychotherapy and occupational therapy, seems to accelerate the process of recovery - and make this more complete - in essentially recoverable cases. (9). With the modified technique described, it is maintained that treatment can be carried out in the normal hospital routine with no great difficult or undue expenditure of time and money

Stability of trusses by graphic statics.

This paper presents a graphical method for determining the linearized stiffness and stability of prestressed trusses consisting of rigid bars connected at pinned joints and which possess kinematic freedoms. Key to the construction are the rectangular areas which combine the reciprocal form and force diagrams in the unified Maxwell-Minkowski diagram. The area of each such rectangle is the product of the bar tension and the bar length, and this corresponds to the rotational stiffness of the bar that arises due to the axial force that it carries. The prestress stability of any kinematic freedom may then be assessed using a weighted sum of these areas. The method is generalized to describe the out-of-plane stability of two-dimensional trusses, and to describe three-dimensional trusses in general. The paper also gives a graphical representation of the 'product forces' that were introduced by Pellegrino and Calladine to describe the prestress stability of trusses

Transformative effects of technology in learning and teaching in first year university science courses

The first part of this study describes the synthesis of a research framework (known as the Transformation Framework) via the analysis of existing literature on technology-related transformation in learning and teaching. The Framework identified five Foundations that were desirable for any implementation of technology in an educational setting and also described three broad types of transformation that might be expected to occur (Institutional, Material and Behavioural). The remainder of the thesis contains a description of the application of the Framework to three science courses in the College of Science and Engineering at a large Scottish university at a point in time when they were attempting to initiate some transformation in learning and teaching, at least in part through the introduction of new technologies. The Framework was used to construct a series of specific interview questions that were designed to illuminate each possible area of transformation. Interviews were then conducted with the Undergraduate Deans who were responsible for the overall initiative of which these courses formed a part and the organisers of each of the three courses (Courses A, B and C). The interview questions were then used to construct an online survey that was used to poll the lecturers and teaching assistants involved in the delivery of each course. Finally, anonymised course marks were obtained for the three courses covering the years before, during and after the innovations were introduced. Using the Framework as a reference, the data sources were then analysed, primarily using NVivo (qualitative data) and SPSS (quantitative data), in order to identify where there may have been transformation perceived or observed, and the evidence supporting the existence of any such transformation was evaluated. Any identified transformations were then analysed further to ascertain any specific contribution that technology may have had to such change. The results provided broad support for the notion that the transformations that may occur are highly context-dependent, and are often influenced by the Foundations that are in place at the time. Course A could be described as “innovation-ready” and as such there was evidence to suggest that the technologies used had several Institutional, Material and Behavioural transformative effects. Course B was more cautious and perhaps less prepared, and yet some Institutional, Material and Behavioural transformations were observed, largely in those areas that were well attended at the Foundation stage. The Course C implementation was done at short notice, and hence with little preparation and as such was very low-key and only limited Material and Behavioural transformations were evident as a result. The research as described above highlights the fact that transformation is far more likely to occur if the proper Foundations have been put in place first, and the technology forms part of an implementation that is well thought-out by the organisers, well supported by the powers-that-be and well accepted by all those who will engage with it. The Framework itself has proved to be a useful and robust guide for this kind of study and it should have value in many different contexts in the future. Applications include not only the evaluation of existing implementations of technology in the classroom but also the planning and preparation of such implementations, informing both the design of a particular course and the choice of technology to achieve specific results

An experimental and computational study of two state of the art living free radical polymerisation techniques

This thesis describes the research conducted by t he author in completion of a Doctor of Philosophy in the Centre for Advanced Macromolecular Design(CAMD), Univcrsity of New South Wales (UNSW) , Sydney, Australia; under the supervision of Professor Christopher Barner-Kowollik and Doctor Michelle L. Coote (Australian National University). The research has led to the creation of new knowledge in the fields of free radical polymerisation and chemical kinetics. Research was conducted in two main thrusts: (1) investigation into the governing kinetic processes behind star polymer synthesis via what has become known as a reversible addition fragmentation chain transfer (RAFT), R-group approach and (2) an entirely new mode of living free radical (LFR) polymerisation which has been named thioketone mediated polymerisation (TKMP). In the first broad area of the described research, a novel kinetic modelling scheme has been developed in which only the reactions of a single arm star are simulated explicitly. Subsequently, the molecular weight distributions (MWDs) arising from the single arm star simulation are convolved, using probabilistic calculations, to generate the MWD appropriate to a multi-arm star polymerisat ion bearing t he same kinetic parameters as the single arm one. This model is validated against experimental data, enabling, for the first time, the use of rigorous theoretical reasoning to distill a set of synthetic guidelines for star polymer synthesis via a RAFT, R-group approach. Subsequently, the product spectra resulting from RAFT, R-group approach polymerisations of para-acetoxystyrene have been analysed via mass spectrometry. This has led to direct evidence for many of the complex species whose existence had, up until this point, been inferred from gel permeation chromatography (GPC) measured MWDs. The menagerie of species identified includes, but is not limited to, star-star couples, initiator fragment terminated stars, initiator fragment terminated star-star couples and linear chains -- both living and terminated. Using a kinetic model devised specifically for application in mass spectrometry analysis, the experimentally observed abundances of each of the above species have been compared to t hose predicted by simulation. The qualitative agreement between the predicted and observed abundances has provided additional evidence that t he proposed mechanism for RAFT, R-group approach polymerisations is correct and operative. Further, it seems unlikely that significant, undiscovered kinetic phenomena exist. Due to (a) long simulation times encountered using the state of the art, commercial partial differential equation solver for polymerisation kinetics (i.e. PREDICI, Computing in Technology (CiT), GmbH; see http://www.cit-wulkow.de) and (b) the limited flexibility this software provides with respect to the types of chemical species that can be simulated, fundamental research has been conducted into the kinetic Monte Carlo method to (i) examine fundamental aspects of this simulation approach; (ii) determine the maximum speed attainable through a combination of optimisations including run-time generation of problem specific code and parallelisation; and, therefore (iii) find out what the potential of this method may be as a replacement for t he existing methods. In terms of speed, the developed code outperforms previous Monte Carlo benchmarks in the literature by a factor of 2.6 and the latest developments in the commercial tool, PREDICI that took place during the author's Ph.D. candidature give it similar performance to the herein described Monte Carlo code; however, the latter is required to run on multiple processors in order to compete with the serial algorithm implemented in PREDICI. The Monte Carlo method does, however, provide complete freedom with respect to the chemical species whose kinetics can be simulated, allowing for complex species with many chain lengths and, in principal copolymer compositions and branched structures. The Monte Carlo approach is the method of choice for these types of simulations and for the first time competes with the commercial tool in terms of speed. In the second broad area of the described research, an experimental investigation has been conducted into the applicability of thioketones, S=C (R1) (R2), as mediating agents for free radical polymerisations. The compound di-tert-butyl thioketone (DTBT), S=C-(C(CH3)3)2, has been chosen as a model reagent and this, when incorporated into a free radical polymerisation of styrene has led to a linear increase of the average molecular weight as conversion of monomer into polymer takes place - demonstrating control. A reversible radical trapping mechanism has been proposed and evidence for this has been provided in the form of an ab initio calculation of the equilibrium constant for the trapping of a styryl dimer radical by DTBT. This equilibrium constant was approximately K = 105 L mol-1 and is close to the value which is expected on the basis of the experimental results. To aid future experimental investigations intoTKMP, a quantum chemical survey has, been conducted with the aim of discovering the radical affinities of a large range of thioketones. It has been demonstrated that there is ample scope within this class of compound for potent radical trapping - far above that of DTBT. The affinities of various thioketone substrates for radicals have been understood in terms of the radical stabilising and thioketone destabilising effect of the two substituents R1 and R2 on, respectively, the adduct radical, R-S-C•(R1) (R2), and the parent thioketone. All results appearing in this thesis have been published previously in peer-reviewed scientific journals

IL-21 receptor expression in human tendinopathy

The pathogenetic mechanisms underlying tendinopathy remain unclear, with much debate as to whether inflammation or degradation has the prominent role. Increasing evidence points toward and early inflammatory infiltrate and associated inflammatory cytokine production in human and animal models of tendon disease. The IL-21/IL-21R axis is a proinflammatory cytokine complex that has been associated with chronic inflammatory diseases including rheumatoid arthritis and inflammatory bowel disease. This project aimed to investigate the role and expression of the cytokine/receptor pair IL-21/IL-21R in human tendinopathy. We found significantly elevated expression of IL-21 receptor message and protein in human tendon samples but found no convincing evidence of the presence of IL-21 at message or protein level. The level of expression of IL-21R message/protein in human tenocytes was significantly up regulated by proinflammatory cytokines (TNFα/IL-1β) in vitro. These findings demonstrate that IL-21R is present in early human tendinopathy mainly expressed by tenocytes and macrophages. Despite a lack of IL-21 expression these data again suggest that early tendinopathy has an inflammatory/cytokine phenotype, which may provide novel translational targets in the treatment of tendinopathy