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Multi-agent learning of asset maintenance plans through localised subnetworks
Get PDFMaintenance planning of networked multi-asset systems is a complex problem due to the inherent individual and collective asset constraints and dynamics as well as the size of the system and interdependencies among assets. Although multi-asset systems have been studied numerous times in the past decades, maintenance planning implications of the system's network characteristics have been barely analysed. Likewise, solutions that consider the network perspective suffer from scalability issues as a network-wide observability is assumed. This paper proposes a network maintenance planning approach based on the decomposition of the multi-asset network into fixed-size localised subnetworks. The overall network maintenance plan is produced by aggregating the subnetwork maintenance plans, which are computed independently via a multi-agent deep reinforcement learning (MARL) algorithm. The results are evaluated against a network-wide approach as well as the commonly-used individual approach. The paper also introduces a systematic approach to integrate the MARL resulting policy in a multi-asset agent-based model. Simulation results of several random asset networks and a large nationwide network infrastructure show that, although a network-wide approach outperforms, on average, other approaches considered, the localised subnetworks approach, provides an acceptable alternative in networks with small-world properties, without the need of a network-wide view
Anticancer effects of the Novel Pyrazolyl-Urea GeGe-3
Get PDFIn a screen of over 200 novel pyrazole compounds, ethyl 1-(2-hydroxypentyl)-5-(3-(3-(trifluoromethyl) phenyl)ureido)-1H-pyrazole-4-carboxylate (named GeGe-3) has emerged as a potential anticancer compound. GeGe-3 displays potent anti-angiogenic properties through the presumptive targeting of the protein kinase DMPK1 and the Ca2+-binding protein calreticulin. We further explored the anticancer potential of GeGe-3 on a range of established cancer cell lines, including PC3 (prostate adenocarcinoma), SKMEL-28 (cutaneous melanoma), SKOV-3 (ovarian adenocarcinoma), Hep-G2 (hepatocellular carcinoma), MDA-MB231, SKBR3, MCF7 (breast adenocarcinoma), A549 (lung carcinoma), and HeLa (cervix epithelioid carcinoma). At concentrations in the range of 10 μM, GeGe-3 significantly restricted cell proliferation and metabolism. GeGe-3 also reduced PC3 cell migration in a standard wound closure and trans-well assay. Together, these results confirm the anticancer potential of GeGe-3 and underline the need for more detailed pre-clinical investigations into its molecular targets and mechanisms of action
Politicisation of science in COVID-19 editorial cartoons: A comparative study of cartoons in Australia, South Africa and the United Kingdom
Get PDFThis study explores the representation of scientists and politicians in editorial cartoons from three countries: Australia, South Africa and the United Kingdom. Of 466 cartoons collected from six Sunday newspapers (two from each country) over an 18 month period, 226 (49%) contained some reference to COVID-19. A qualitative analysis of cartoons highlights the politicisation of science and the relative absence of scientists in the cartoon discourse. Cartoonists fail to address the reasons for the imposition of COVID-19 related restrictions or the effectiveness of such health measures. Instead, cartoonists focus on the restrictions themselves, often portraying politicians as juggling competing demands and scientists as in opposition to the relaxation of social restrictions. In addressing COVID-19 in this way, cartoonists subtly suggest conflicts between the values of scientists, politicians and society. Cartoonists also tie the pandemic into broader political discourses pertinent in each country, for example, states rights in Australia, corruption in South Africa and Brexit in the UK
Simulated autopoiesis in liquid automata
Get PDFWe present a novel form of Liquid Automata, using this to simulate autopoiesis, whereby living machines self-organise in the physical realm. This simulation is based on an earlier Cellular Automaton described by Francisco Varela. The basis of Liquid Automata is a particle simulation with additional rules about how particles are transformed on collision with other particles. Unlike cellular automata, there is no fixed grid or time-step, only particles moving about and colliding with each other in a continuous space/time
Emerging evidence for nurse-led interventions in patients with systemic lupus erythematosus and systemic sclerosis
Get PDFClimate change and modern slavery in public procurement
No full textExisting links between modern slavery and climate change are becoming clearer as the need increases for a just transition to a low-carbon economy. Yet, how organisations attempt to address these risks, either separately or simultaneously, is not understood in depth. In particular, the role of public procurement, which can be a powerful method for driving responsible behaviours into public and private operations alike, remains conceptually understood but under-investigated.We sought, through this project, to address this important knowledge gap by engaging with the public procurement ecosystem. We partnered with London Universities Purchasing Consortium (LUPC) and UK modern slavery charity Unseen UK to work with those organisations and, through LUPC, with public buyers and their suppliers and risk management data platforms. We ultimately conducted over 70 hours of interviews and focus groups with professionals and consultants, including those with lived experience of the issue at those organisations.We developed recommendations for public purchasing through a study of: (i) the actions that public sector buyers are taking to manage the risks of modern slavery and climate change in their operations and supply chains; (ii) the actions that tier 1 and tier 2 suppliers to the public sector are taking to address these risks; (iii) the role of public sector purchasing consortia in managing modern slavery and climate change risks through public tendering and contract management on behalf of public buyers; (iv) how and the extent to which the sustainability data platforms used by public buyers to assist in decision making and risk management work for their public sector clients. By studying the factors involved from a multi-party perspective, we intended to better understand the links between the efforts of the various stakeholders involved in responsible procurement in the public sector.Through members of LUPC and consultants introduced to us by Unseen UK, who have lived experience of modern slavery, we were able to triangulate our findings in two focus groups. In this way, we gained valuable insights from different perspectives on the findings of the study and to enhance the recommendations we were developing.The report contains five overarching findings which further inform our specific findings and recommendations
“One dead bedroom”: Exploring the lived experience of sex and sexuality for women with self-reported obsessive-compulsive disorder
Get PDFThis study explored lived experiences of sexuality for women with self-reported obsessive-compulsive disorder (OCD), with a particular focus on the felt impact of OCD on their sexual identities, practices and relationships, and their experiences of help-seeking. One hundred and thirty-four women completed an online qualitative survey. One Skype interview was also undertaken at the request of a participant. We analysed the data using reflexive thematic analysis and developed four themes: ‘My distorted reality’; ‘OCD as sex killjoy’; ‘What is normal sex?’, and ‘I’m scared and you’re not helping’. The participants reported experiencing anxiety around their ‘true’ sexuality and distinguishing between authentic sexual thoughts and intrusive thoughts. They managed the anxiety associated with intrusive thoughts by avoiding sex as much as possible, or altogether. Women who talked about sex in therapy experienced judgements about their sexuality and sexist advice. The analysis locates the distress the women experienced within a patriarchal and heteronormative social context. We argue that dominate discourses around sex and gender have material and embodied consequences for the participants as they navigated their sexual identities and relationships
A systematic review of the effectiveness of reading comprehension interventions in the South African multilingual context
Get PDFInternational comparative measures show that South Africa has extremely low standards in reading. A variety of programmes aimed at boosting reading have been developed, however, the effectiveness of these programmes is unclear. Prior reviews of effective reading instruction practices have focused almost exclusively on learners whose first language and language of instruction is English. This paper reviews evidence from 17 intervention studies which focused on the teaching of reading comprehension in the distinctive multilingual context of South Africa. Although in line with prior reviews, we found some evidence that reading strategy instruction including vocabulary development are features of successful interventions alongside effective teacher education and resourcing of reading. These findings remained inconclusive due to variability in the quality of research, considerable methodological variations of the studies and the limited number of studies. Research in this field requires a more rigorous scientific approach to improve the evidence base
Cyclic voltammetric behaviour and high-performance liquid chromatography amperometric determination of levamisole
Get PDFThe electrochemical oxidation of levamisole, a glassy carbon electrode, was investigated over the pH range 2.0–10.0. Cyclic voltammetric investigations showed a single oxidation process was recorded, with a peak potential (Ep) shown to be pH-dependent in the range 5.0–8.0; between pH 2.0 and pH 5.0, and above pH 8.0, the Ep was found to be independent of pH, indicating apparent pKa values of 5.0 and 8.0. Peak currents were found to increase with increasing pH values. This voltammetric oxidation process was found to be consistent with a two-electron, two-proton oxidation to the corresponding sulfoxide. Based on these findings, the development of a of method based on the high-performance liquid chromatography separation of levamisole, with electrochemical detection being used for its determination, was explored. The chromatographic conditions required for the separation of levamisole were first investigated and optimized using UV detection. The conditions were identified as a 150 mm × 4.6 mm, 5 µm C18 column with a mobile phase consisting of 50% methanol, and 50%, 50 mM, pH 8.0 phosphate buffer. The technique of hydrodynamic voltammetry was applied to optimize the applied potential required for the determination of levamisole, identified as +2.3 V versus a stainless-steel pseudo-reference counter-electrode. Under the optimized conditions, levamisole exhibited a linear response of 1.00–20 mg/L (R2 = 0.999), with a detection limit of 0.27 mg/L. The possibility of determining levamisole in artificial urine was shown to be possible via simple dilution in the mobile phase. Mean recoveries of 99.7%, and 94.6%, with associated coefficients of variation of 8.2% and 10.2%, respectively, were obtained for 1.25 µg/mL (n = 5) and 2.50 µg/mL (n = 5)