• UbiD domain dynamics underpins aromatic decarboxylation

      Marshall, Stephen A.; orcid: 0000-0001-7678-4989; email: stephen.marshall@chem.ox.ac.uk; Payne, Karl A. P.; orcid: 0000-0002-6331-6374; Fisher, Karl; orcid: 0000-0003-3539-8939; Titchiner, Gabriel R.; orcid: 0000-0002-6378-9884; Levy, Colin; Hay, Sam; orcid: 0000-0003-3274-0938; Leys, David; orcid: 0000-0003-4845-8443; email: david.leys@manchester.ac.uk (Nature Publishing Group UK, 2021-08-20)
      Abstract: The widespread UbiD enzyme family utilises the prFMN cofactor to achieve reversible decarboxylation of acrylic and (hetero)aromatic compounds. The reaction with acrylic compounds based on reversible 1,3-dipolar cycloaddition between substrate and prFMN occurs within the confines of the active site. In contrast, during aromatic acid decarboxylation, substantial rearrangement of the substrate aromatic moiety associated with covalent catalysis presents a molecular dynamic challenge. Here we determine the crystal structures of the multi-subunit vanillic acid decarboxylase VdcCD. We demonstrate that the small VdcD subunit acts as an allosteric activator of the UbiD-like VdcC. Comparison of distinct VdcCD structures reveals domain motion of the prFMN-binding domain directly affects active site architecture. Docking of substrate and prFMN-adduct species reveals active site reorganisation coupled to domain motion supports rearrangement of the substrate aromatic moiety. Together with kinetic solvent viscosity effects, this establishes prFMN covalent catalysis of aromatic (de)carboxylation is afforded by UbiD dynamics.
    • Ultra-Structural Imaging Provides 3D Organization of 46 Chromosomes of a Human Lymphocyte Prophase Nucleus

      Sajid, Atiqa; email: atiqa.sajid@aku.edu; Lalani, El-Nasir; email: elnasir.lalani@aku.edu; Chen, Bo; orcid: 0000-0001-7515-3042; email: bo.chen@tongji.edu.cn; Hashimoto, Teruo; email: T.Hashimoto@Manchester.ac.uk; Griffin, Darren K.; orcid: 0000-0001-7595-3226; email: D.K.Griffin@kent.ac.uk; Bhartiya, Archana; email: a.bhartiya@ucl.ac.uk; Thompson, George; email: george.thompson@manchester.ac.uk; Robinson, Ian K.; orcid: 0000-0003-4897-5221; email: i.robinson@ucl.ac.uk; Yusuf, Mohammed; email: mohammed.yusuf@aku.edu (MDPI, 2021-06-01)
      Three dimensional (3D) ultra-structural imaging is an important tool for unraveling the organizational structure of individual chromosomes at various stages of the cell cycle. Performing hitherto uninvestigated ultra-structural analysis of the human genome at prophase, we used serial block-face scanning electron microscopy (SBFSEM) to understand chromosomal architectural organization within 3D nuclear space. Acquired images allowed us to segment, reconstruct, and extract quantitative 3D structural information about the prophase nucleus and the preserved, intact individual chromosomes within it. Our data demonstrate that each chromosome can be identified with its homolog and classified into respective cytogenetic groups. Thereby, we present the first 3D karyotype built from the compact axial structure seen on the core of all prophase chromosomes. The chromosomes display parallel-aligned sister chromatids with familiar chromosome morphologies with no crossovers. Furthermore, the spatial positions of all 46 chromosomes revealed a pattern showing a gene density-based correlation and a neighborhood map of individual chromosomes based on their relative spatial positioning. A comprehensive picture of 3D chromosomal organization at the nanometer level in a single human lymphocyte cell is presented.
    • Ultra-thin g-C

      Liu, Chengcheng; Luo, Tian; Sheveleva, Alena M; Han, Xue; Kang, Xinchen; orcid: 0000-0003-0593-0840; Sapchenko, Sergei; Tuna, Floriana; orcid: 0000-0002-5541-1750; McInnes, Eric J L; Han, Buxing; orcid: 0000-0003-0440-809X; Yang, Sihai; orcid: 0000-0002-1111-9272; et al. (2021-07-05)
      growth of the metal-organic framework material MFM-300(Fe) on an ultra-thin sheet of graphitic carbon nitride (g-C N ) has been achieved exfoliation of bulk carbon nitride using supercritical CO . The resultant hybrid structure, CNNS/MFM-300(Fe), comprising carbon nitride nanosheets (CNNS) and MFM-300(Fe), shows excellent performance towards photocatalytic aerobic oxidation of benzylic C-H groups at room temperature under visible light. The catalytic activity is significantly improved compared to the parent g-C N , MFM-300(Fe) or physical mixtures of both. This facile strategy for preparing heterojunction photocatalysts demonstrates a green pathway for the efficient and economic oxidation of benzylic carbons to produce fine chemicals. [Abstract copyright: This journal is © The Royal Society of Chemistry.]
    • Ultrafast Electric Field-Induced Phase Transition in Bulk Bi0.5Na0.5TiO3 under High-Intensity Terahertz Irradiation

      Zhang, Man; McKinnon, Ruth A.; Viola, Giuseppe; Yang, Bin; Zhang, Dou; orcid: 0000-0001-8555-2784; Reece, Michael J.; orcid: 0000-0002-2293-7123; Abrahams, Isaac; orcid: 0000-0002-8606-6056; Yan, Haixue; orcid: 0000-0002-4563-1100 (American Chemical Society (ACS), 2020-12-10)
    • Ultraviolet light-induced collagen degradation inhibits melanoma invasion

      Budden, Timothy; Gaudy-Marqueste, Caroline; Porter, Andrew; orcid: 0000-0002-3353-7002; Kay, Emily; Gurung, Shilpa; Earnshaw, Charles H.; orcid: 0000-0002-7926-8506; Roeck, Katharina; Craig, Sarah; orcid: 0000-0003-1928-582X; Traves, Víctor; Krutmann, Jean; orcid: 0000-0001-8433-1517; et al. (Nature Publishing Group UK, 2021-05-12)
      Abstract: Ultraviolet radiation (UVR) damages the dermis and fibroblasts; and increases melanoma incidence. Fibroblasts and their matrix contribute to cancer, so we studied how UVR modifies dermal fibroblast function, the extracellular matrix (ECM) and melanoma invasion. We confirmed UVR-damaged fibroblasts persistently upregulate collagen-cleaving matrix metalloprotein-1 (MMP1) expression, reducing local collagen (COL1A1), and COL1A1 degradation by MMP1 decreased melanoma invasion. Conversely, inhibiting ECM degradation and MMP1 expression restored melanoma invasion. Primary cutaneous melanomas of aged humans show more cancer cells invade as single cells at the invasive front of melanomas expressing and depositing more collagen, and collagen and single melanoma cell invasion are robust predictors of poor melanoma-specific survival. Thus, primary melanomas arising over collagen-degraded skin are less invasive, and reduced invasion improves survival. However, melanoma-associated fibroblasts can restore invasion by increasing collagen synthesis. Finally, high COL1A1 gene expression is a biomarker of poor outcome across a range of primary cancers.
    • Ultraviolet light-induced collagen degradation inhibits melanoma invasion.

      Budden, Timothy; Gaudy-Marqueste, Caroline; Porter, Andrew; orcid: 0000-0002-3353-7002; Kay, Emily; Gurung, Shilpa; Earnshaw, Charles H; orcid: 0000-0002-7926-8506; Roeck, Katharina; Craig, Sarah; orcid: 0000-0003-1928-582X; Traves, Víctor; Krutmann, Jean; orcid: 0000-0001-8433-1517; et al. (2021-05-12)
      Ultraviolet radiation (UVR) damages the dermis and fibroblasts; and increases melanoma incidence. Fibroblasts and their matrix contribute to cancer, so we studied how UVR modifies dermal fibroblast function, the extracellular matrix (ECM) and melanoma invasion. We confirmed UVR-damaged fibroblasts persistently upregulate collagen-cleaving matrix metalloprotein-1 (MMP1) expression, reducing local collagen (COL1A1), and COL1A1 degradation by MMP1 decreased melanoma invasion. Conversely, inhibiting ECM degradation and MMP1 expression restored melanoma invasion. Primary cutaneous melanomas of aged humans show more cancer cells invade as single cells at the invasive front of melanomas expressing and depositing more collagen, and collagen and single melanoma cell invasion are robust predictors of poor melanoma-specific survival. Thus, primary melanomas arising over collagen-degraded skin are less invasive, and reduced invasion improves survival. However, melanoma-associated fibroblasts can restore invasion by increasing collagen synthesis. Finally, high COL1A1 gene expression is a biomarker of poor outcome across a range of primary cancers.
    • Ultraviolet light-induced collagen degradation inhibits melanoma invasion.

      Budden, Timothy; Gaudy-Marqueste, Caroline; Porter, Andrew; orcid: 0000-0002-3353-7002; Kay, Emily; Gurung, Shilpa; Earnshaw, Charles H; orcid: 0000-0002-7926-8506; Roeck, Katharina; Craig, Sarah; orcid: 0000-0003-1928-582X; Traves, Víctor; Krutmann, Jean; orcid: 0000-0001-8433-1517; et al. (2021-05-12)
      Ultraviolet radiation (UVR) damages the dermis and fibroblasts; and increases melanoma incidence. Fibroblasts and their matrix contribute to cancer, so we studied how UVR modifies dermal fibroblast function, the extracellular matrix (ECM) and melanoma invasion. We confirmed UVR-damaged fibroblasts persistently upregulate collagen-cleaving matrix metalloprotein-1 (MMP1) expression, reducing local collagen (COL1A1), and COL1A1 degradation by MMP1 decreased melanoma invasion. Conversely, inhibiting ECM degradation and MMP1 expression restored melanoma invasion. Primary cutaneous melanomas of aged humans show more cancer cells invade as single cells at the invasive front of melanomas expressing and depositing more collagen, and collagen and single melanoma cell invasion are robust predictors of poor melanoma-specific survival. Thus, primary melanomas arising over collagen-degraded skin are less invasive, and reduced invasion improves survival. However, melanoma-associated fibroblasts can restore invasion by increasing collagen synthesis. Finally, high COL1A1 gene expression is a biomarker of poor outcome across a range of primary cancers.
    • UN treaty-based bodies and the Islamic Republic of Iran: Human rights dialogue (1990–2016)

      Moinipour, Shabnam; orcid: 0000-0003-1764-0832; Bendall, Mark (Informa UK Limited, 2018-03-02)
    • Unbiased estimation of the gradient of the log-likelihood in inverse problems

      Jasra, Ajay; Law, Kody J. H.; orcid: 0000-0003-3133-2537; email: kody.law@manchester.ac.uk; Lu, Deng (Springer US, 2021-03-03)
      Abstract: We consider the problem of estimating a parameter θ∈Θ⊆Rdθ associated with a Bayesian inverse problem. Typically one must resort to a numerical approximation of gradient of the log-likelihood and also adopt a discretization of the problem in space and/or time. We develop a new methodology to unbiasedly estimate the gradient of the log-likelihood with respect to the unknown parameter, i.e. the expectation of the estimate has no discretization bias. Such a property is not only useful for estimation in terms of the original stochastic model of interest, but can be used in stochastic gradient algorithms which benefit from unbiased estimates. Under appropriate assumptions, we prove that our estimator is not only unbiased but of finite variance. In addition, when implemented on a single processor, we show that the cost to achieve a given level of error is comparable to multilevel Monte Carlo methods, both practically and theoretically. However, the new algorithm is highly amenable to parallel computation.
    • Uncertainty, Anxiety and Isolation: Experiencing the COVID-19 Pandemic and Lockdown as a Woman with Polycystic Ovary Syndrome (PCOS)

      Atkinson, Lou; email: l.atkinson1@aston.ac.uk; Kite, Chris; orcid: 0000-0003-1342-274X; email: c.kite@chester.ac.uk; McGregor, Gordon; orcid: 0000-0001-8963-9107; email: ac4378@coventry.ac.uk; James, Tamsin; email: jamestno@aston.ac.uk; Clark, Cain C. T.; orcid: 0000-0002-6610-4617; email: ad0183@coventry.ac.uk; Randeva, Harpal S.; email: harpal.randeva@uhcw.nhs.uk; Kyrou, Ioannis; email: ad6702@coventry.ac.uk (MDPI, 2021-09-25)
      Background: The COVID-19 pandemic and the related lockdown measures presented a significant risk to physical and mental wellbeing in affected populations. Women with polycystic ovary syndrome (PCOS) are predisposed to several cardio-metabolic risk factors which increase the susceptibility to severe COVID-19 and also exhibit increased likelihood of impaired mental health wellbeing. Therefore, these women who usually receive care from multiple primary and specialist healthcare services may be disproportionately impacted by this pandemic and the related restrictions. This study aimed to explore the lived experience of the first UK national lockdown as a woman with PCOS. Methods: As part of a larger cross-sectional study, 12 women with PCOS living in the UK during the first national COVID-19 lockdown were recruited to a qualitative study. Telephone interviews were conducted in June/July of 2020, and data collected were subjected to thematic analysis. Results: Five themes were identified. “My PCOS Journey” describes participants’ experiences of diagnosis, treatment and ongoing management of their PCOS. “Living Through Lockdown” describes the overall experience and impact of the lockdown on all aspects of participants’ lives. “Self-care and Managing Symptoms” describe multiple challenges to living well with PCOS during the lockdown, including lack of access to supplies and services, and disruption to weight management. “Healthcare on Hold” describes the uncertainty and anxiety associated with delays in accessing specialised healthcare for a range of PCOS aspects, including fertility treatment. “Exacerbating Existing Issues” captures the worsening of pre-existing mental health issues, and an increase in health anxiety and feelings of isolation. Conclusion: For the women with PCOS in this study, the COVID-19 pandemic and the first national lockdown was mostly experienced as adding to the pre-existing challenges of living with their condition. The mental health impact experienced by the study participants was increased due to lack of access to their normal support strategies, limitations on healthcare services and uncertainty about their risk of COVID-19.
    • Uncertainty, Anxiety and Isolation: Experiencing the COVID-19 Pandemic and Lockdown as a Woman with Polycystic Ovary Syndrome (PCOS).

      Atkinson, Lou; Kite, Chris; orcid: 0000-0003-1342-274X; McGregor, Gordon; orcid: 0000-0001-8963-9107; James, Tamsin; Clark, Cain C T; orcid: 0000-0002-6610-4617; Randeva, Harpal S; Kyrou, Ioannis (2021-09-25)
      The COVID-19 pandemic and the related lockdown measures presented a significant risk to physical and mental wellbeing in affected populations. Women with polycystic ovary syndrome (PCOS) are predisposed to several cardio-metabolic risk factors which increase the susceptibility to severe COVID-19 and also exhibit increased likelihood of impaired mental health wellbeing. Therefore, these women who usually receive care from multiple primary and specialist healthcare services may be disproportionately impacted by this pandemic and the related restrictions. This study aimed to explore the lived experience of the first UK national lockdown as a woman with PCOS. As part of a larger cross-sectional study, 12 women with PCOS living in the UK during the first national COVID-19 lockdown were recruited to a qualitative study. Telephone interviews were conducted in June/July of 2020, and data collected were subjected to thematic analysis. Five themes were identified. "My PCOS Journey" describes participants' experiences of diagnosis, treatment and ongoing management of their PCOS. "Living Through Lockdown" describes the overall experience and impact of the lockdown on all aspects of participants' lives. "Self-care and Managing Symptoms" describe multiple challenges to living well with PCOS during the lockdown, including lack of access to supplies and services, and disruption to weight management. "Healthcare on Hold" describes the uncertainty and anxiety associated with delays in accessing specialised healthcare for a range of PCOS aspects, including fertility treatment. "Exacerbating Existing Issues" captures the worsening of pre-existing mental health issues, and an increase in health anxiety and feelings of isolation. For the women with PCOS in this study, the COVID-19 pandemic and the first national lockdown was mostly experienced as adding to the pre-existing challenges of living with their condition. The mental health impact experienced by the study participants was increased due to lack of access to their normal support strategies, limitations on healthcare services and uncertainty about their risk of COVID-19.
    • Uncovering genetic mechanisms of hypertension through multi-omic analysis of the kidney.

      Eales, James M; orcid: 0000-0001-6238-5952; Jiang, Xiao; orcid: 0000-0002-1442-8927; Xu, Xiaoguang; orcid: 0000-0003-4568-1623; Saluja, Sushant; Akbarov, Artur; Cano-Gamez, Eddie; McNulty, Michelle T; Finan, Christopher; orcid: 0000-0002-3319-1937; Guo, Hui; orcid: 0000-0003-0282-6933; Wystrychowski, Wojciech; et al. (2021-05-06)
      The kidney is an organ of key relevance to blood pressure (BP) regulation, hypertension and antihypertensive treatment. However, genetically mediated renal mechanisms underlying susceptibility to hypertension remain poorly understood. We integrated genotype, gene expression, alternative splicing and DNA methylation profiles of up to 430 human kidneys to characterize the effects of BP index variants from genome-wide association studies (GWASs) on renal transcriptome and epigenome. We uncovered kidney targets for 479 (58.3%) BP-GWAS variants and paired 49 BP-GWAS kidney genes with 210 licensed drugs. Our colocalization and Mendelian randomization analyses identified 179 unique kidney genes with evidence of putatively causal effects on BP. Through Mendelian randomization, we also uncovered effects of BP on renal outcomes commonly affecting patients with hypertension. Collectively, our studies identified genetic variants, kidney genes, molecular mechanisms and biological pathways of key relevance to the genetic regulation of BP and inherited susceptibility to hypertension.
    • Understanding acceptability in the context of text messages to encourage medication adherence in people with type 2 diabetes

      Bartlett, Y. Kiera; email: kiera.bartlett@manchester.ac.uk; Kenning, Cassandra; Crosland, Jack; Newhouse, Nikki; Miles, Lisa M.; Williams, Veronika; McSharry, Jenny; Locock, Louise; Farmer, Andrew J.; French, David P. (BioMed Central, 2021-06-28)
      Abstract: Background: Acceptability is recognised as a key concept in the development of health interventions, but there has been a lack of consensus about how acceptability should be conceptualised. The theoretical framework of acceptability (TFA) provides a potential tool for understanding acceptability. It has been proposed that acceptability measured before use of an intervention (anticipated acceptability) may differ from measures taken during and after use (experienced acceptability), but thus far this distinction has not been tested for a specific intervention. This paper 1) directly compares ratings of anticipated and experienced acceptability of a text message-based intervention, 2) explores the applicability of the TFA in a technology-based intervention, and 3) uses these findings to inform suggestions for measuring acceptability over the lifespan of technology-based health interventions. Methods: Data were obtained from a quantitative online survey assessing anticipated acceptability of the proposed text messages (n = 59) and a 12-week proof-of-concept mixed methods study assessing experienced acceptability while receiving the text messages (n = 48). Both quantitative ratings by return text message, and qualitative data from participant interviews were collected during the proof-of-concept study. Results: The quantitative analysis showed anticipated and experienced acceptability were significantly positively correlated (rs > .4). The qualitative analysis identified four of the seven constructs of the TFA as themes (burden, intervention coherence, affective attitude and perceived effectiveness). An additional two themes were identified as having an important impact on the TFA constructs (perceptions of appropriateness and participants’ role). Three suggestions are given related to the importance of appropriateness, what may affect ratings of acceptability and what to consider when measuring acceptability. Conclusions: The high correlation between anticipated and experienced acceptability was a surprising finding and could indicate that, in some cases, acceptability of an intervention can be gauged adequately from an anticipated acceptability study, prior to an expensive pilot or feasibility study. Directly exploring perceptions of appropriateness and understanding whether the acceptability described by participants is related to the intervention or the research - and is for themselves or others - is important in interpreting the results and using them to further develop interventions and predict future use.
    • Understanding minimum and ideal factor levels for participation in physical activities by people with haemophilia: An expert elicitation exercise

      Martin, Antony P.; orcid: 0000-0003-4383-6038; Burke, Tom; Asghar, Sohaib; Noone, Declan; Pedra, Gabriel; orcid: 0000-0002-2023-5224; O'Hara, Jamie (Wiley, 2020-04-08)
    • Understanding minimum and ideal factor levels for participation in physical activities by people with haemophilia: An expert elicitation exercise

      Martin, Antony P.; orcid: 0000-0003-4383-6038; Burke, Tom; Asghar, Sohaib; Noone, Declan; Pedra, Gabriel; orcid: 0000-0002-2023-5224; O'Hara, Jamie (Wiley, 2020-04-08)
    • Understanding PITX2-Dependent Atrial Fibrillation Mechanisms through Computational Models

      Bai, Jieyun; email: baijieyun@jnu.edu.cn; Lu, Yaosheng; email: tluys@jnu.edu.cn; Zhu, Yijie; email: zyj1934261010@stu2019.jnu.edu.cn; Wang, Huijin; email: twanghj@jnu.edu.cn; Yin, Dechun; email: yindechun0429@163.com; Zhang, Henggui; email: henggui.zhang@manchester.ac.uk; Franco, Diego; orcid: 0000-0002-5669-7164; email: dfranco@ujaen.es; Zhao, Jichao; email: j.zhao@auckland.ac.nz (MDPI, 2021-07-19)
      Atrial fibrillation (AF) is a common arrhythmia. Better prevention and treatment of AF are needed to reduce AF-associated morbidity and mortality. Several major mechanisms cause AF in patients, including genetic predispositions to AF development. Genome-wide association studies have identified a number of genetic variants in association with AF populations, with the strongest hits clustering on chromosome 4q25, close to the gene for the homeobox transcription PITX2. Because of the inherent complexity of the human heart, experimental and basic research is insufficient for understanding the functional impacts of PITX2 variants on AF. Linking PITX2 properties to ion channels, cells, tissues, atriums and the whole heart, computational models provide a supplementary tool for achieving a quantitative understanding of the functional role of PITX2 in remodelling atrial structure and function to predispose to AF. It is hoped that computational approaches incorporating all we know about PITX2-related structural and electrical remodelling would provide better understanding into its proarrhythmic effects leading to development of improved anti-AF therapies. In the present review, we discuss advances in atrial modelling and focus on the mechanistic links between PITX2 and AF. Challenges in applying models for improving patient health are described, as well as a summary of future perspectives.
    • Understanding regional value chains through the interaction of public and private governance: Insights from Southern Africa’s apparel sector

      Pasquali, Giovanni; email: giovanni.pasquali@manchester.ac.uk; Godfrey, Shane; Nadvi, Khalid (Palgrave Macmillan UK, 2020-09-23)
      Abstract: Regional value chains (RVCs) and South–South trade are increasingly considered key features of 21st-century globalisation. This article investigates how RVCs are shaped by the interaction of private and public governance. It evaluates how this interaction unfolded in Southern Africa’s apparel RVCs, exploring trade, investment and labour regimes across three levels of analysis: national, regional, and global. The paper draws on trade data, secondary literature, and interviews with suppliers and institutions in Eswatini and Lesotho (the largest exporters to the region), and lead firms in South Africa (the largest regional importer). The findings underline the critical role of public governance in shaping retailers’ and suppliers’ participation in RVCs through: (i) regional ‘trade regimes’ protecting regional exporters from global competitors, and recent shifts in global trade regimes; (ii) national and regional ‘investment regimes’ facilitating investment flows from South Africa to Lesotho and Eswatini, and the more recent shift of US-oriented suppliers towards regional markets; and (iii) ‘labour regimes’, including lower wages, less comprehensive labour legislation and weaker trade unions in Lesotho and Eswatini compared to South Africa. The article concludes by considering the policy implications of the interaction of private and public governance for existing and future RVCs in Sub-Saharan Africa.
    • Understanding regional value chains through the interaction of public and private governance: Insights from Southern Africa’s apparel sector

      Pasquali, Giovanni; email: giovanni.pasquali@manchester.ac.uk; Godfrey, Shane; Nadvi, Khalid (Palgrave Macmillan UK, 2020-09-23)
      Abstract: Regional value chains (RVCs) and South–South trade are increasingly considered key features of 21st-century globalisation. This article investigates how RVCs are shaped by the interaction of private and public governance. It evaluates how this interaction unfolded in Southern Africa’s apparel RVCs, exploring trade, investment and labour regimes across three levels of analysis: national, regional, and global. The paper draws on trade data, secondary literature, and interviews with suppliers and institutions in Eswatini and Lesotho (the largest exporters to the region), and lead firms in South Africa (the largest regional importer). The findings underline the critical role of public governance in shaping retailers’ and suppliers’ participation in RVCs through: (i) regional ‘trade regimes’ protecting regional exporters from global competitors, and recent shifts in global trade regimes; (ii) national and regional ‘investment regimes’ facilitating investment flows from South Africa to Lesotho and Eswatini, and the more recent shift of US-oriented suppliers towards regional markets; and (iii) ‘labour regimes’, including lower wages, less comprehensive labour legislation and weaker trade unions in Lesotho and Eswatini compared to South Africa. The article concludes by considering the policy implications of the interaction of private and public governance for existing and future RVCs in Sub-Saharan Africa.
    • Understanding the electrochemistry of "water-in-salt" electrolytes: basal plane highly ordered pyrolytic graphite as a model system.

      Iamprasertkun, Pawin; Ejigu, Andinet; Dryfe, Robert A W; orcid: 0000-0002-9335-4451 (2020-06-08)
      A new approach to expand the accessible voltage window of electrochemical energy storage systems, based on so-called "water-in-salt" electrolytes, has been expounded recently. Although studies of transport in concentrated electrolytes date back over several decades, the recent demonstration that concentrated aqueous electrolyte systems can be used in the lithium ion battery context has rekindled interest in the electrochemical properties of highly concentrated aqueous electrolytes. The original aqueous lithium ion battery conception was based on the use of concentrated solutions of lithium bis(trifluoromethanesulfonyl)imide, although these electrolytes still possess some drawbacks including cost, toxicity, and safety. In this work we describe the electrochemical behavior of a simple 1 : 1 electrolyte based on highly concentrated aqueous solutions of potassium fluoride (KF). Highly ordered pyrolytic graphite (HOPG) is used as well-defined model carbon to study the electrochemical properties of the electrolyte, as well as its basal plane capacitance, from a microscopic perspective: the KF electrolyte exhibits an unusually wide potential window (up to 2.6 V). The faradaic response on HOPG is also reported using K<sub>3</sub>Fe(CN)<sub>6</sub> as a model redox probe: the highly concentrated electrolyte provides good electrochemical reversibility and protects the HOPG surface from adsorption of contaminants. Moreover, this electrolyte was applied to symmetrical supercapacitors (using graphene and activated carbon as active materials) in order to quantify its performance in energy storage applications. It is found that the activated carbon and graphene supercapacitors demonstrate high gravimetric capacitance (221 F g<sup>-1</sup> for activated carbon, and 56 F g<sup>-1</sup> for graphene), a stable working voltage window of 2.0 V, which is significantly higher than the usual range of water-based capacitors, and excellent stability over 10 000 cycles. These results provide fundamental insight into the wider applicability of highly concentrated electrolytes, which should enable their application in future of energy storage technologies.
    • Understanding the electrochemistry of "water-in-salt" electrolytes: basal plane highly ordered pyrolytic graphite as a model system.

      Iamprasertkun, Pawin; Ejigu, Andinet; Dryfe, Robert A W; orcid: 0000-0002-9335-4451 (2020-06-08)
      A new approach to expand the accessible voltage window of electrochemical energy storage systems, based on so-called "water-in-salt" electrolytes, has been expounded recently. Although studies of transport in concentrated electrolytes date back over several decades, the recent demonstration that concentrated aqueous electrolyte systems can be used in the lithium ion battery context has rekindled interest in the electrochemical properties of highly concentrated aqueous electrolytes. The original aqueous lithium ion battery conception was based on the use of concentrated solutions of lithium bis(trifluoromethanesulfonyl)imide, although these electrolytes still possess some drawbacks including cost, toxicity, and safety. In this work we describe the electrochemical behavior of a simple 1 : 1 electrolyte based on highly concentrated aqueous solutions of potassium fluoride (KF). Highly ordered pyrolytic graphite (HOPG) is used as well-defined model carbon to study the electrochemical properties of the electrolyte, as well as its basal plane capacitance, from a microscopic perspective: the KF electrolyte exhibits an unusually wide potential window (up to 2.6 V). The faradaic response on HOPG is also reported using K Fe(CN) as a model redox probe: the highly concentrated electrolyte provides good electrochemical reversibility and protects the HOPG surface from adsorption of contaminants. Moreover, this electrolyte was applied to symmetrical supercapacitors (using graphene and activated carbon as active materials) in order to quantify its performance in energy storage applications. It is found that the activated carbon and graphene supercapacitors demonstrate high gravimetric capacitance (221 F g for activated carbon, and 56 F g for graphene), a stable working voltage window of 2.0 V, which is significantly higher than the usual range of water-based capacitors, and excellent stability over 10 000 cycles. These results provide fundamental insight into the wider applicability of highly concentrated electrolytes, which should enable their application in future of energy storage technologies. [Abstract copyright: This journal is © The Royal Society of Chemistry.]