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Legitimacy, Power, and Aesthetics, in the International Baccalaureate
No full textThis paper explores the facilitation of the emancipatory in an International Baccalaureate (IB) context of privilege. It aligns with the idea that capitalism, even in welfare state democracies or ‘do good’ corporations, maintains the interests of the owners of capital. It is by nature unjust and exploitative and must conceal this injustice by securing a (spurious) legitimacy for itself (Edgar, 2006, p. 88). This makes a rare methodological contribution as the article provides critical ‘meta-analysis’ (Card, 2015) of IB research literature by prioritising work that affords insight into the lived reality within the IB-Sphere. It then triangulates this analysis through the work of German Social Philosopher Jürgen Habermas (1970; 1981; 1983; 1989; 1991).This work provides a significant and timely contribution to ‘franchised education’ (Apple, 2000; Ball, 2012) in the 21st Century, and will be of essential reading to scholars, policy makers and leadership whether involved in the IB, or active in the Neo Liberal spaces of education more generally: such as Multi Trust Academies, Free Schools, or Charter Schools. This is thanks to the lessons learned over nearly 60 years of educational franchise in a diverse and globalising sphere as presented here from IB research through critical analysis. <br/
Customized Multi-Energy Pricing in Smart Grids: A Bilevel and Evolutionary Computation Approach
No full textThis paper proposes a customized energy pricing scheme for energy retailers in multi-energy (i.e., electricity and natural gas) retail markets. Microgrids with distributed energy resources (DERs) and demand response (DR) programs are considered on the demand side. We adopt a bilevel single-leader multi-follower model to analyze the customized multi-energy pricing decisions where the retailer’s profit maximization problem is formulated at the upper level, and the microgrids’ operation costs minimization problems are considered at the lower level. A particle swarm optimization (PSO) based evolutionary solution approach is developed to solve the proposed bilevel decision-making problem. Through a numerical case study, we demonstrate the feasibility and effectiveness of the proposed bilevel model and the solution algorithm. We reveal that the proposed customized pricing scheme could offer differentiated optimal pricing decisions to various microgrids characterized by their energy conversion efficiencies
Antiplatelet resistance: a review of concepts, mechanisms and implications for management in acute ischaemic stroke and transient ischaemic attack
No full textAcute ischaemic stroke is a leading cause of death and major disability worldwide. Approximately 50% of ischaemic strokes are caused by atherothrombotic occlusion of the cerebral arteries and antiplatelets are the mainstay of secondary stroke preventative treatment. Aspirin is beneficial if given early and short-term treatment using aspirin and clopidogrel is increasingly used for patients with intracranial atherosclerotic disease, minor stroke and/or transient ischemic attack. However, up to 50% of patients continue to have recurrent stroke and major vascular events, which may be partly due to resistance to aspirin and/or clopidogrel. Although the precise mechanisms are unknown, clinical and genetic factors associated with bioavailability and binding to target receptors are implicated. This narrative review begins with the concept of aspirin and clopidogrel resistance in ischaemic stroke and transient ischaemic attack (TIA), potential mechanisms including genetic polymorphisms and an overview of platelet function measures and limitations. We conclude by highlighting practical issues in the management of patients with aspirin and/or clopidogrel resistance including the emerging interest in ticagrelor, prasugrel and cilostazol and directions for future trials in TIA and acute ischaemic stroke
Mechanism of melatonin metabolism by CYP1A1. What determines the bifurcation pathways of hydroxylation versus deformylation?
No full textMelatonin, a widely consumed cosmetic active ingredient, has a variety of uses as skin protector through antioxidant and anti-inflammatory functions as well as giving the body UV-induced defenses and immune system support. In the body, melatonin is synthesized from a tryptophan amino acid in a cascade of reactions, but as melatonin is toxic at high concentrations it is metabolized in the human skin by the cytochrome P450 enzymes. The P450s are diverse heme based monooxygenases that catalyze oxygen atom transfer processes that trigger metabolism and detoxification in the body. In the cata-lytic cycle of the P450s, a short-lived high-valent iron(IV)-oxo heme cation radical is formed that has been proposed to be the active oxidant. How and why it activates melatonin in the human body and what the origin of the product distributions is, are unknown. This encouraged us to do a detailed computational study on a typical human P450 isozyme, namely CYP1A1. We initially did a series of molecular dynamics simulations with substrate docked into several orientations. These simulations reveal several stable substrate-bound orientations in the active site, which may lead to differences in substrate activation channels. Using tunneling analysis on the full protein structures, we show that two of the four binding conformations lead to open substrate binding pockets. As a result, in these open pockets the substrate is not tightly bound and can escape back into the solution. In the closed conformations, by contrast, the substrate is mainly oriented with the methoxy group pointing toward the heme, although under a different angle. We then created large quantum cluster models of the enzyme and focused on the chemical reaction mechanisms for melatonin activation leading to competitive O-demethylation and C6-aromatic hydroxylation pathways. The calculations show that active site positioning determines the product distributions, but the bond that is activated is not necessarily closest to the heme in the enzyme-substrate complex. As such, the docking and molecular dynamics positioning of substrate versus oxidant gives misleading predictions on product distributions. In particular, in QM cluster model I we observe that through a tight hydrogen bonding network a preferential 6-hydroxylation of melatonin is obtained. However, O-demethylation becomes possible in alternative substrate-binding orientations that have the C6-aro-matic ring position shielded. Finally, we investigated enzymatic and non-enzymatic O-demethylation processes and show that the hydrogen bonding network in the substrate binding pocket can assist and perform this step prior to product release from the enzyme
Mechanisms of Electron Transfer Rate Modulations in Cytochrome P450 BM3.
No full textThe bacterial cytochromes P450 BM3 (CYP450 BM3) catalyzes reactions of industrial importance. Despite many successful biotransformations, robust re(design) for novel applications remains challenging. Rational design and evolution-ary approaches are not always successful highlighting a lack of complete understanding of the mechanisms of electron trans-fer (ET) modulations. Thus, the full potential of CYP450 reactions remains under-exploited. In this work, we report the first MD-based explicit prediction of BM3 ET parameters (reorganization energies; λ and ET free energies; ΔG°), and log ET rates (log kET) using Marcus theory. Overall, the calculated ET rates for the BM3 wild-type (WT), mutants (F393 and L86), ligand-bound state, and ion concentrations agree well with experimental data. In ligand-free (LF) BM3, mutations modulate kET via ET ΔG°. Simulations show that the experimental ET rate enhancement is due to increased driving force (more negative ΔG°) upon ligation. This increase is related to the protein reorganization required to accommodate the ligand in the binding pocket, rather than binding interaction with the ligand. Our methodology (CYPWare 1.0) automates all the stages of MD simulation step-up, energy calculations, and estimation of ET parameters. CYPWare 1.0 and this work, thus represent an important advancement in the CYP450 ET rate predictions which has the potential to guide the redesign of ET enzymes. This program and a web tool are available on GitHub for academic research
Antiracism CoaliTION in Pain Research (ACTION-PR): Guiding Principles for Equity in Reporting
No full textWriting and Reading Together from Colonial Legacy to World-making:The case of Algerian bilingual authors
No full textKateb Yacine told Geneviève Serreau in 1956 that one does not use a universal language to humiliate a people in its very soul without consequences: sooner or later, the people seize that language and culture for themselves on their way towards freedom. Following this prophecy, Algerian intellectuals have in effect appropriated the French language, which they deploy with a high level of proficiency to address the colonizer in its own language. However, with decolonization, the French language was probed as a legacy of colonialism and an obstacle to Algerian self-realization and cultural authenticity. Algerian governments implemented a top-down Arabization policy, excluding national differences and subscribing wholly to the group of Arab nations. This process alienated those who did not read or speak Arabic in a country that is essentially comprised of a multiplicity of languages, cultures, and identities. This article delves into this bitter polemic as a painstaking search for national identity. It traces the position of the French language in the Algerian intellectual and literary landscape, from an initial gesture of rejection to a later move toward appropriation and nativization
Recall of exposure in UK farmers and pesticide applicators:trends with follow-up time
No full textBACKGROUND: Occupational epidemiological studies on pesticide use commonly rely on self-reported questionnaire or interview data to assess exposure. Insight into recall accuracy is important, as misclassification of exposures due to imperfect recall can bias risk estimates.METHODS: We assessed the ability of workers in three UK cohorts (Prospective Investigation of Pesticide Applicators' Health [PIPAH], Pesticide Users' Health Study [PUHS], and Study of Health in Agricultural Work [SHAW]) to remember their working history related to pesticide exposure over time periods ranging from 3 to 14 years prior. During 2019-2020, cohort participants were re-surveyed using a similar questionnaire to that used previously. We compared recall of responses at follow-up to those reported at baseline related to crops/areas of work, use of personal protective equipment (PPE) items, hygiene habits, frequency of pesticide use, and application method. To assess the extent of recall, we used sensitivity, specificity, the percentage of overall agreement, and area under the curve (AUC) values. We also examined the presence of over or underestimation of recalled years, and days and hours per year, of working with pesticides using geometric mean ratios (GMR) and regression analysis to investigate any trends based on demographic characteristics.RESULTS: There were 643 individuals who completed both the baseline and follow-up surveys in the three cohorts with response rates ranging from 17 to 46%. There was a strong correlation (rho = 0.77) between the baseline and recalled years working with pesticides, though higher values were reported at follow-up (GMR = 1.18 [95% confidence interval: 1.07-1.30]) with no consistent differences by demographic characteristics. There was stronger agreement in the recalled days compared to hours per year in two of the cohorts. Recall for a number of exposure determinants across short and longer periods entailed overall agreement of >70%, though with some differences: for example, sensitivity for long-term recall of crops was poor (<43% in PUHS), whereas short-term recall of hygiene practices was good (AUC range = 0.65-1.00 in PIPAH).CONCLUSION: Results indicate that recall ability may deteriorate over a longer period. Although low-response rates may require these findings to be interpreted with caution, recall for a number of exposure determinants appeared reliable, such as crops and hygiene practices within 3 years, as well as days per year working with pesticides.</p
Robust Formation Control for Networked Robotic Systems Using Negative Imaginary Dynamics
No full textThis paper proposes a consensus-based formation tracking scheme for multi-robot systems utilising the Negative Imaginary (NI) theory. The proposed scheme applies to a class of networked robotic systems that can be modelled as a group of single integrator agents with stable uncertainties connected via an undirected graph. NI/SNI property of networked agents facilitates the design of a distributed Strictly Negative Imaginary (SNI) controller to achieve the desired formation tracking. A new theoretical proof of asymptotic convergence of the formation tracking trajectories is derived based on the integral controllability of a networked SNI systems. The proposed scheme is an alternative to the conventional Lyapunov-based formation tracking schemes. It offers robustness to NI/SNI-type model uncertainties and fault-tolerance to a sudden loss of robots due to hardware/communication fault. The feasibility and usefulness of the proposed formation tracking scheme were validated by lab-based real-time hardware experiments involving miniature mobile robots
‘Enter Parliament but never become part of it’: How have the Greens in the UK Approached Opposition?
No full textThe Greens in the UK have benefited from the fragmentation of the party system and the creation of devolved institutions, achieving consistent representation at multiple levels of British politics in recent years. However, we know little about what they have done in these positions. This study uses interviews with Green legislators to investigate how they have interpreted the task of opposition at Westminster, Holyrood and Stormont. We show that Green legislators’ approaches to opposition have been influenced by their party identity, and that differences in approach between the institutions have largely been determined by contrasting political opportunity structures, rather than parliamentary rules. These findings highlight the importance of party as a factor shaping opposition strategy and the varied roles which opposition parties can play within the UK political system