Formalization of the fundamental group in untyped set theory using auto2

We present a new framework for formalizing mathematics in untyped set theory using auto2. Using this framework, we formalize in Isabelle/FOL the entire chain of development from the axioms of set theory to the definition of the fundamental group for an arbitrary topological space. The auto2 prover is used as the sole automation tool, and enables succinct proof scripts throughout the project.Comment: 17 pages, accepted for ITP 201

An Empirical Study of 'Fringe Benefits' and Performance of the Korean Firms

This paper examines the effects of fringe benefits in the compensation package on performance of the Korean firms. Theoretically, fringe benefits have two implications in relation to employees: they are effective instruments that provide incentives; at the same time, some fringe benefits, especially the power-related benefits, are often used for exploitation of self-interests. Using a six-year panel data of the Korean manufacturing firms, we do a regression analysis and identify the links between fringe benefits and performance of the Korean firms. Our results suggest that, in general, these types of compensations do not promote good performance of firms. The results also imply that perhaps some designs in pay for performance in Korea are not efficient.published_or_final_versio

Network-analysis-guided synthesis of weisaconitine D and liljestrandinine.

General strategies for the chemical synthesis of organic compounds, especially of architecturally complex natural products, are not easily identified. Here we present a method to establish a strategy for such syntheses, which uses network analysis. This approach has led to the identification of a versatile synthetic intermediate that facilitated syntheses of the diterpenoid alkaloids weisaconitine D and liljestrandinine, and the core of gomandonine. We also developed a web-based graphing program that allows network analysis to be easily performed on molecules with complex frameworks. The diterpenoid alkaloids comprise some of the most architecturally complex and functional-group-dense secondary metabolites isolated. Consequently, they present a substantial challenge for chemical synthesis. The synthesis approach described here is a notable departure from other single-target-focused strategies adopted for the syntheses of related structures. Specifically, it affords not only the targeted natural products, but also intermediates and derivatives in the three families of diterpenoid alkaloids (C-18, C-19 and C-20), and so provides a unified synthetic strategy for these natural products. This work validates the utility of network analysis as a starting point for identifying strategies for the syntheses of architecturally complex secondary metabolites

Sustainable built asset management performance indicators and attributes : a UK social housing case study example

This paper aims to identify key performance indicators (KPI), and their corresponding attributes, required to successfully manage asset management sustainably in a built environment context. Improving the sustainability of existing housing stock is a major challenge facing the UK social housing sector. There is a lack of support to navigate the growing and often incongruent information relating to sustainable development and how to operationalise it. The problem is twofold; firstly, the current (single criterion) condition-based approach to maintenance planning constrains Asset Managers and does not fully address the social, environmental and economic aspects of sustainability. Secondly, the toolkits available for assessing the sustainability of housing are often generic and are time consuming and expensive to implement. This paper reports the findings of a participatory research project with a leading London based housing association, using a series of landlord and tenant workshops to derive a set of attributes associated with key performance indicators (KPIs) to fully reflect the local requirements of the landlord and their interpretation of the sustainability agenda. Five KPIs considered to be measurable, directly affected by maintenance work and independent of each other were identified by this landlord (comfort, running costs, adaptability, maintenance costs and community).The resulting outputs, in a policy context, will provide a clear route-map to social housing landlords of how to improve the sustainability of their housing stock with the additional benefits of addressing fuel poverty, carbon emissions targets whilst at the same time help create and maintain housing in which people want to live. The proposed approach is flexible enough to incorporate the individual requirements of landlords, be able to adapt to changes in government policy (local and central) in a timely, robust, transparent and inclusive format

Biochemical properties of Paracoccus denitrificans FnrP:Reactions with molecular oxygen and nitric oxide

In Paracoccus denitrificans, three CRP/FNR family regulatory proteins, NarR, NnrR and FnrP, control the switch between aerobic and anaerobic (denitrification) respiration. FnrP is a [4Fe-4S] cluster containing homologue of the archetypal O2 sensor FNR from E. coli and accordingly regulates genes encoding aerobic and anaerobic respiratory enzymes in response to O2, and also NO, availability. Here we show that FnrP undergoes O2-driven [4Fe-4S] to [2Fe-2S] cluster conversion that involves up to 2 O2 per cluster, with significant oxidation of released cluster sulfide to sulfane observed at higher O2 concentrations. The rate of the cluster reaction was found to be ~6-fold lower than that of E. coli FNR, suggesting that FnrP can remain transcriptionally active under microaerobic conditions. This is consistent with a role for FnrP in activating expression of the high O2 affinity cytochrome c oxidase under microaerobic conditions. Cluster conversion resulted in dissociation of the transcriptionally active FnrP dimer into monomers. Therefore, along with E. coli FNR, FnrP belongs to the subset of FNR proteins in which cluster type is correlated with association state. Interestingly, two key charged residues, Arg140 and Asp154, that have been shown to play key roles in the monomer-dimer equilibrium in E. coli FNR are not conserved in FnrP, indicating that different protomer interactions are important for this equilibrium. Finally, the FnrP [4Fe-4S] cluster is shown to undergo reaction with multiple NO molecules, resulting in iron nitrosyl species and dissociation into monomers

Formulation and performance of variational integrators for rotating bodies

Variational integrators are obtained for two mechanical systems whose configuration spaces are, respectively, the rotation group and the unit sphere. In the first case, an integration algorithm is presented for Euler’s equations of the free rigid body, following the ideas of Marsden et al. (Nonlinearity 12:1647–1662, 1999). In the second example, a variational time integrator is formulated for the rigid dumbbell. Both methods are formulated directly on their nonlinear configuration spaces, without using Lagrange multipliers. They are one-step, second order methods which show exact conservation of a discrete angular momentum which is identified in each case. Numerical examples illustrate their properties and compare them with existing integrators of the literature

Efficacy of selective laser trabeculoplasty for normal tension glaucoma: 1 year results

BACKGROUND: Normal tension glaucoma (NTG) is commonly treated with anti-glaucoma medications. Recently, selective laser trabeculoplasty (SLT) has been demonstrated to lower the intraocular pressure (IOP) and medication use in NTG. The purpose of this study was to investigate the efficacy of a single session of SLT for NTG at 1 year. METHODS: This prospective cohort study recruited NTG patients taking anti-glaucoma medication. Potential subjects were excluded if they had had previous glaucoma surgery or laser and also if intraocular surgery or additional SLT procedures were performed after the first treatment. All subjects underwent a 1-month washout. A 30% IOP reduction was set as the target IOP. A single session of SLT was performed to 360 degrees of the trabecular meshwork. At 1-month after SLT, medication was resumed to achieve the target IOP. The IOP was measured every 3 months, and the number of medications was recorded at 3, 6, and 12 months. Only the right eye was used for statistical analysis. RESULTS: In 41 right eyes, the mean pre-study IOP was 14.3 +/- 3.4 mmHg while on 1.5 +/- 0.8 eye drops. The post-washout IOP was 16.2 +/- 2.2 mmHg. A mean of 191.1 +/- 26.3 SLT shots at 1.0 +/- 0.07 mJ were applied. There was significant IOP reduction at all time intervals following SLT when compared to the post-washout IOP (P < 0.0001). The number of medications was significantly reduced at all time intervals following SLT when compared to the pre-study level (P < 0.0001). At 12 months, the mean IOP was 12.2 +/- 2.2 mmHg while on 1.1 +/- 0.9 eye drops. CONCLUSIONS: A single session of SLT for NTG achieved an additional 15% IOP reduction while using 27% less medication at 1 year compared to pre-study levels.Trial registration: The Clinical Trials Register of the University of Hong Kong HKCTR1847The European Clinical Trials Database 2014-003305-15 (August 11, 2014) (https://eudract.ema.europa.eu/).published_or_final_versio

Phonological and phonetic properties of nasal substitution in Sasak and Javanese

Austronesian languages such as Sasak and Javanese have a pattern of morphological nasal substitution, where nasals alternate with homorganic oral obstruents—except that [s] is described as alternating with [ɲ], not with [n]. This appears to be an abstract morphophonological relation between [s] and [ɲ] where other parts of the paradigm have a concrete homorganic relation. Articulatory ultrasound data were collected of productions of [t, n, ʨ, ɲ], along with [s] and its nasal counterpart from two languages, from 10 Sasak and 8 Javanese speakers. Comparisons of lingual contours using a root mean square analysis were evaluated with linear mixed-effects regression models, a method that proves reliable for testing questions of phonological neutralization. In both languages, [t, n, s] exhibit a high degree of articulatory similarity, whereas postalveolar [ʨ] and its nasal counterpart [ɲ] exhibited less similarity. The nasal counterpart of [s] was identical in articulation to [ɲ]. This indicates an abstract, rather than concrete, relationship between [s] and its morphophonological nasal counterpart, with the two sounds not sharing articulatory place in either Sasak or Javanese.published_or_final_versio