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We initiate a new, computational approach to a classical problem: certifying non-freeness of ($2$-generator, parabolic) M\"{o}bius subgroups of $\mathrm{SL}(2,\mathbb{Q})$. The main tools used are algorithms for Zariski dense groups and algorithms to compute a presentation of $\mathrm{SL}(2, R)$ for a localization $R= \mathbb{Z}[\frac{1}{b}]$ of $\mathbb{Z}$. We prove that a M\"{o}bius subgroup $G$ is not free by showing that it has finite index in the relevant $\mathrm{SL}(2, R)$. Further information about the structure of $G$ is obtained; for example, we compute the minimal subgroup of finite index in $\mathrm{SL}(2,R)$ that contains $G$.

We initiate a new, computational approach to a classical problem: certifying non-freeness of ($2$-generator, parabolic) Möbius subgroups of $\mathrm{SL}(2,\mathbb{Q})$. The main tools used are algorithms for Zariski dense groups and algorithms to compute a presentation of $\mathrm{SL}(2, R)$ for a localization $R= \mathbb{Z}[\frac{1}{b}]$ of $\mathbb{Z}$. We prove that a Möbius subgroup $G$ is not free by showing that it has finite index in the relevant $\mathrm{SL}(2, R)$. Further information about the structure of $G$ is obtained; for example, we compute the minimal subgroup of finite index in $\mathrm{SL}(2,R)$ that contains $G$.

Let $p$ be a prime and let $\mathbb{C}$ be the complex field. We explicitly classify the finite solvable irreducible monomial subgroups of $\mathrm{GL}(p,\mathbb{C})$ up to conjugacy. That is, we give a complete and irredundant list of $\mathrm{GL}(p,\mathbb{C})$-conjugacy class representatives as generating sets of monomial matrices. Copious structural information about non-solvable finite irreducible monomial subgroups of $\mathrm{GL}(p,\mathbb{C})$ is also proved, enabling a classification of all such groups bar one family. We explain the obstacles in that exceptional case. For $p\leq 3$, we classify all finite irreducible subgroups of $\mathrm{GL}(p,\mathbb{C})$. Our classifications are available publicly in Magma.

We survey aspects of locally nilpotent linear groups. Then we obtain a new classification; namely, we classify the irreducible maximal locally nilpotent subgroups of $\mathrm{GL}(q, \mathbb F)$ for prime $q$ and any field $\mathbb F$.

A 78-year-old man with a long history of polyarteritis nodosa, ischaemic heart disease, chronic kidney disease and a cavitating lung lesion with mycobacterium malmoense was admitted with generalised muscular pain, fatigue, anorexia, decreased mobility and dizziness over the last month. His sputum had recently cultured aspergillus fumigatus and he had commenced on voriconazole six weeks prior. His maintenance therapy for polyarteritis was long term prednisolone and mycophenolate mofetil. His examination demonstrated that he was normotensive with generalised muscular tenderness, ankle oedema, an aortic murmur, bronchial breathing of the left upper lobe but was otherwise unremarkable with a normal postural blood pressure. Bloods demonstrated normal inflammatory markers, a new transaminitis, deteriorating renal function with urea of 37 and hyperkalaemia at 6.2, which required treatment. ANCA tests were negative. A synacthen test was inadequate with cortisol rising from 136 to 268 nmol/L at 30 minutes. Hypoadrenalism due to long-term steroid use was a working diagnosis. His prednisolone was increased to 20mg and he received intramuscular depomedrone 120mg. His voriconazole, mycophenolate and anti-tuberculous drugs were stopped 4 days post admission. He was discussed with renal who felt uraemia wasn’t driving his symptoms and agreed there was no evidence of vasculitis relapse. A random morning cortisol checked 12 days post admission was 463nmol/L. He could now mobilise independently and his renal/liver function returned to baseline. It was felt that the voriconazole was the culprit agent and he didn’t restart this on discharge, after consultation with respiratory.

We introduce almost supplementary difference sets (ASDS). For odd $m$, certain ASDS in ${\mathbb Z}_m$ that have amicable incidence matrices are equivalent to quaternary sequences of odd length $m$ with optimal autocorrelation. As one consequence, if $2m-1$ is a prime power, or $m \equiv 1 \mod 4$ is prime, then ASDS of this kind exist. We also explore connections to optimal binary sequences and group cohomology.

This chapter reads the recent theatrical adaptation of Ayn Rand's 1943 novel _The Fountainhead_ by Toneelgroep Amsterdam (TGA). It considers the adaptation as a new departure for its director, Ivo van Hove who, prior to 2014, had consistently claimed that he had no interest in bringing novels to the stage. The chapter then goes on to consider the specifics of how van Hove reads Rand's novel as an argument for human creativity and freedom in a way that is resonant with the ideology of films (many from the 1960s and 70s) that TGA have adapted. It considers the specifics of Van Hove's adaptation under the four headings of Cinema, Writing, Love and Light.

This groundbreaking, cross-generic collection is the first to consider the entire breadth of Alan Hollinghurst's Booker Prize-winning writing. Focused through the concept of influence, the volume addresses critical issues surrounding the work of Britain's most important contemporary novelist. It encompasses provocative and timely subjects ranging from gay visual cultures and representations, to Victorian, modernist and contemporary literature, as well as race and empire, theatre and cinema, eros and economics. The book reveals the fascinating intellectual and affective matter that lies beneath the polished control and dazzling style of Hollinghurst's work. Alongside contributions by distinguished British and American critics, the book includes an unpublished interview with Hollinghurst. Alan Hollinghurst: Writing under the influence uses a creative range of critical approaches to provide the most authoritative and innovative account available of Hollinghurst's works.

We survey the legacy of L.G. Kov��cs in linear group theory, with a particular focus on classification questions.

This groundbreaking, cross-generic collection is the first to consider the entire breadth of Alan Hollinghurst's Booker Prize-winning writing. Focused through the concept of influence, the volume addresses critical issues surrounding the work of Britain's most important contemporary novelist. It encompasses provocative and timely subjects ranging from gay visual cultures and representations, to Victorian, modernist and contemporary literature, as well as race and empire, theatre and cinema, eros and economics. The book reveals the fascinating intellectual and affective matter that lies beneath the polished control and dazzling style of Hollinghurst's work. Alongside contributions by distinguished British and American critics, the book includes an unpublished interview with Hollinghurst. Alan Hollinghurst: Writing under the influence uses a creative range of critical approaches to provide the most authoritative and innovative account available of Hollinghurst's works.

Written in the form of a dialogue between editors Michele Mendelssohn and Denis Flannery, this introduction explores the book's principles and summarises its specific chapters. Emphasising the extent to which the collection is a historically-tessellated exploration of the breadth of Hollinghurst's output, it explores the varied ways in which he is in dialogue with his various influences. For the writers in this collection, a sense of 'influence' emerges that is, while genial and accepting, also not devoid of antagonism and shadow. The extent to which susceptibility to influence can be read as a form of intoxication as well as a world-making state of primal vulnerability is also emphasised. The introduction stresses the extent to which Hollinghurst breaks new ground even as he prowls the precincts of well-established literary traditions. These traditions extend beyond the novel and encompass poetry, translation and theatre in his oeuvre which is also, the book also emphasises, richly in dialogue with cinema as a cultural force and with recent developments in critical theory.

In this paper we present a theoretical model of higher education participation in Ireland. Utilising the Living in Ireland Survey data we model the impact of costs (direct and indirect), the estimated life cycle returns, environmental and parental influences and also household credit constraints on the higher education participation decision. We find that foregone earnings and youth employment rates have a negative impact on this decision; this suggests weaker labour markets for young people may have a positive impact on higher education participation. The insignificance of credit constraints in the shape of household income and maintenance grant eligibility from our estimations can also help draw some tentative policy conclusions. Our results also show that life cycle returns and parental educational level may influence participation in higher education in Ireland.

Although originally designed by and for the use of the Neutron and X-ray communities, the flexibility of the NeXus data format makes it equally suitable for storing data gathered from MuSR experiments. Furthermore, its use should open up the possibility of sharing software beyond the immediate muon community; giving access to the many tools that are already in existence for manipulating NeXus and HDF based files. This paper explores the development of the NeXus format for storing ISIS muon data and the associated experimental conditions. The design of an Instrument Definition for the ISIS muon instruments is described and the implementation of an application to translate the present ISIS raw data format to the NeXus format presented. The development of a common muon data format is a topic of active discussion within the muon community; with this in mind, the suitability of NeXus and, in particular, the ISIS Instrument Definition for general application is considered. A number of applications that have been developed to exploit the flexibility of the ISIS muon NeXus file format are described and a scheme for enabling web based browsing and analysis of experiment data is introduced., Comment: "Paper for NOBUGS2002 Conference, NIST, Gaithersburg, MD. Poster submission. NOBUGS abstract identifier: NOBUGS2002/028 10 pages, Postscript, PDF file available at http://www.isis.rl.ac.uk/NOBUGS2002/ "

Fibre optic chemical sensing has been demonstrated using side-polished single mode optical bre, evanescently coupled to chemically sensitive Langmuir-Blodgett overlay waveguides. The sensors exhibit a channel dropping response centred on a wavelength dependent upon the thickness and refractive index of the overlay waveguide. It has been shown that chemically sensitive organic dyes prove to be suitable materials for forming the overlay waveguide whereas the Langmuir-Blodgett deposition technique provides the required overlay thickness control. A brief optic pH sensor has been demonstrated by depositing a merocyanine dye onto a side-polished optical fibre which exhibits a change in transmission of 9.7 ± 0.8 dB pH" at a working wavelength of 750 n and 4.2 ± 0.5 dB pH`1 at 780 nm, with a shift in the channel dropping centre wavelength of 18.8 ± 0.8 n pH`1. The response time of the sensor to a step change in pH has been measured to be ~ 20 s. The advantage of being able to chemically engineer the organic materials used to form the overlay waveguides has been demonstrated by manufacturing a second pH sensor designed to operate at longer wavelengths using a second, modified merocyanine dye. The overall wavelength response of this second sensor to pH has been shown to be non- linear but a sensitivity of 23.3 ± 0.3 n pH`l is observed over a linear region. Finally, i order to investigate the non-linear response, a computer model based on the Kramers- Kronig relations has been devised and shows good agreement with experimental values. l

An unusual nucleolar organizer region (NOR) heteromorphism was noted among 13 of 41 parents in whom nondisjunction leading to trisomy 21 was known to have occurred. In contrast, only one of these double NOR (dNOR) variants was found among the 41 normal spouses and none were seen among 50 control individuals. In two dNOR(+) families, a second child with trisomy 21 was conceived. In both families, the extra chromosome in each child was contributed by the parent who carried the dNOR variant and resulted from a recurrent meiosis I error. Our data suggest that the dNOR heteromorphism may play a role in meiotic nondisjunction and could be associated with as much as a 20-fold increased risk for having offspring with trisomy 21.

With increasing numbers of young people participating in higher education in Ireland and a heavy reliance of higher education institutions on State funding, the introduction of an alternative finance system for Ireland has been muted over the past number of years. However, no study has been conducted to gauge the potential impact of such measures. In this paper we utilise a dynamic microsimulation model developed for Ireland to simulate the impact of both an income contingent loan system (ICL) and a graduate tax system from a fiscal and redistributional viewpoint and to analyse the repayment length under the former system. Our results suggest that an ICL system could be more equitable, while the graduate tax system could be a better alternative from a fiscal viewpoint. The results also illustrate the importance of the interest rate attached to any future student loan system within Ireland from a fiscal viewpoint

This paper outlines how a discrete choice experiment (DCE) can be used to learn more about how students are willing to trade off various features of assignments such as the nature and timing of feedback and the method used to submit assignments. A DCE identifies plausible levels of the key attributes of a good or service and then presents the respondent with alternative bundles of these attributes and their levels and asks the respondent to choose between particular bundles. We report results from a DCE we conducted with undergraduate business students regarding their preferences for assignment systems. We find that the most important features of assignments are how relevant the assignments are for exam preparation and the nature of the feedback that students receive. We also find that students generally prefer online to paper assignments. We argue that the DCE approach has a lot of potential in education research. Accessed 4,497 times on https://pareonline.net from November 13, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.

Stack, K. et al., The Mars 2020 Perseverance rover landing site is located within Jezero crater, a ∼50km diameter impact crater interpreted to be a Noachian-aged lake basin inside the western edge of the Isidis impact structure. Jezero hosts remnants of a fluvial delta, inlet and outlet valleys, and infill deposits containing diverse carbonate, mafic, and hydrated minerals. Prior to the launch of the Mars 2020 mission, members of the Science Team collaborated to produce a photogeologic map of the Perseverance landing site in Jezero crater. Mapping was performed at a 1:5000 digital map scale using a 25 cm/pixel High Resolution Imaging Science Experiment (HiRISE) orthoimage mosaic base map and a 1 m/pixel HiRISE stereo digital terrain model. Mapped bedrock and surficial units were distinguished by differences in relative brightness, tone, topography, surface texture, and apparent roughness. Mapped bedrock units are generally consistent with those identified in previously published mapping efforts, but this study’s map includes the distribution of surficial deposits and sub-units of the Jezero delta at a higher level of detail than previous studies. This study considers four possible unit correlations to explain the relative age relationships of major units within the map area. Unit correlations include previously published interpretations as well as those that consider more complex interfingering relationships and alternative relative age relationships. The photogeologic map presented here is the foundation for scientific hypothesis development and strategic planning for Perseverance’s exploration of Jezero crater., With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737)

Written in the form of a dialogue between editors Michele Mendelssohn and Denis Flannery, this introduction explores the book's principles and summarises its specific chapters. Emphasising the extent to which the collection is a historically-tessellated exploration of the breadth of Hollinghurst's output, it explores the varied ways in which he is in dialogue with his various influences. For the writers in this collection, a sense of 'influence' emerges that is, while genial and accepting, also not devoid of antagonism and shadow. The extent to which susceptibility to influence can be read as a form of intoxication as well as a world-making state of primal vulnerability is also emphasised. The introduction stresses the extent to which Hollinghurst breaks new ground even as he prowls the precincts of well-established literary traditions. These traditions extend beyond the novel and encompass poetry, translation and theatre in his oeuvre which is also, the book also emphasises, richly in dialogue with cinema as a cultural force and with recent developments in critical theory.