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High-performance metal oxide nanoparticle materials synthesised using polar aprotic solvents for advanced supercapacitor applications
No full textYesWe report on a newly developed, surfactant free and scalable methodology for the synthesis of spherical nanoparticles of nickel hydroxide [Ni(OH)2] and nickel oxide (NiO), employing the polar, aprotic solvent, dimethylformamide (DMF), and evaluate their potential for electrochemical battery-type supercapacitor applications. The material synthesis methodology was extended to the hybrid nanomaterial nickel hydroxide-manganese dioxide [Ni(OH)2-MnO2] and, with the addition of SDBS, manganese dioxide (MnO2) nanoparticles. The resulting nanostructured materials were comprehensively characterized by various structural, morphological, and thermal techniques. Of all electrode materials investigated in three-electrode configuration, surfactant free NiO and α-Ni(OH)2-MnO2 exhibit the highest specific capacities with values of 312.42 mAh g-1 and 348.61 mAh g-1 at a current density of 1 A g-1, respectively. In symmetric devices, where surfactant free NiO and α-Ni(OH)2-MnO2 were employed as the active layers, specific capacities of 94.31 mAh g-1 and 139.43 mAh g-1 at a current density of 1 A g-1 and energy densities of 47.21 Wh kg-1 and 69.72 Wh kg-1 at a power density of 1 kW kg-1 respectively have been measured. The devices have a maximum capacity retention of 86.50% and 90.18% after 5000 charge-discharge cycles at 3 A g-1 demonstrating that they also possess high cycle stability. These results confirm the viability of the rational design methodology employed here for the surfactant free synthesis of electrode materials for deployment in energy storage applications.Commonwealth Scholarship Commission (CSC) for financial support through the Split-Site programme (PKCN-2019-175). UKIERI-DST Partnership (IND/CONT/G/17-18/36)
Lanthanide (Er, Eu)-Doped TiO2 with Enhanced Kinetics for a High-Performance Asymmetric Supercapacitor and Oxygen Evolution Reaction
No full textNoSupercapacitor performance is generally hindered by sluggish electrode reaction kinetics, which can be improved through doping to create surface defects, oxygen vacancies, and active sites. Pristine TiO2, Er-doped, Eu-doped, and Er/Eu-codoped TiO2 nanoparticles were synthesized via a solution-based method. Among all of the electrodes fabricated, Er/Eu-codoped TiO2 showed the highest specific capacitance of 1772.5 F g−1 at 1 A g−1 and a low charge transfer resistance of 12.37 Ω, highlighting the enhanced electrical conductivity and rapid ion and electron transport. The Er/Eu-codoped TiO2 electrode was further investigated in asymmetric supercapacitor geometry, where it demonstrated a wide potential window of 1.6 V, a specific capacitance of 135 F g−1 at 2 A g−1, an energy density of 48 Wh kg−1, and a power density of 1.6 kW kg−1. Additionally, pristine TiO2, Er-doped, Eu-doped, and Er/Eu-codoped TiO2 exhibited excellent oxygen evolution reaction performance, with onset potentials of 1.57, 1.52, 1.49, and 1.47 V and low overpotentials of 460, 400, 380, and 290 mV at 20 mA cm−2. The electrodes exhibited excellent electrochemical stability when tested for 20 h using constant potential electrolysis. Tafel slopes of 166.11, 164.71, 139.08, and 115.19 mV dec−1 suggested that all of the electrocatalysts under study are promising materials for OER research. These findings confirm that TiO2 codoped with rare earth metals is an appealing electrode material for energy storage as well as energy generation.Commonwealth Scholarship Commission (CSC) Split-Site program (PKCN-2019-175
The Long-term Effect of Civil Conflict on Psychological Well-being
Get PDFYesA growing literature shows that exposure to civil conflict could have long-term effects on psychological well-being in adulthood. This paper examines the long-term effects of exposure to the Nigerian civil war on the psychological well-being of heads of household using a difference-in-differences approach. We find that exposure to the civil war is associated with an increase in depressive score or symptoms in later life. We also find gender and locational differences in the effects of the civil war on depressive symptoms. The findings of this paper reveal that illness, household income, ownership of formal accounts, access to electricity, and unemployment, are some of the potential mechanisms through which exposure to conflict could affect depressive symptoms in later life. The findings of this paper support the hypothesis that exposure to shocks such as conflict could have deleterious consequences on well-being in later life
Solvatomorphism of a 2,6-pyridyldicarboxamide-based foldamer
No full textYesA detailed solvatomorphism study conducted on a diamine-terminated 2,6-pyridyldicarboxamide-based foldamer 1 is reported. This investigation establishes the influence of a diverse range of polar and non-polar solvents including chloroform (1A), a trifluorotoluene/dichloromethane mixture (1A), dimethyl-formamide/diethyl ether (1B), tetrahydrofuran (1·THF), butanone (1·butanone), dichloromethane (1·DCM), a methanol/dichloromethane mixture (1·MeOH) and dimethylsulfoxide (1·DMSO) on the solid-state conformation and crystal packing behaviour of this supramolecular scaffold. Single-crystal X-ray diffraction analysis of the seven solvatomorphs of the studied foldamer (1A, 1B, 1·DCM, 1·THF, 1·butanone, 1·MeOH and 1·DMSO) identi ed that 1·DCM, 1·THF, 1·butanone, 1·MeOH and 1·DMSO form supramolecular aggregates (e.g., channels/cavities) which incorporate solvent molecules within the voids of the system, leading them to adopt channels of differing dimensions between 3.5 and 9.0 Å. Solid-state analysis identified that a diverse array of intermolecular non-covalent interactions form between the foldamer and the solvent molecule, including N–H⋯O, N–H⋯Cl, O–H⋯O, N–H⋯Cl and C–H⋯O hydrogen-bonding interactions, stabilising the formation of these solvent-mediated channel aggregates within the different solvatomorphs of the studied foldamer. We envisage that these solvatomorphism studies will facilitate the future design of foldamers, particularly given the emerging solid-state applications of foldamers which could hold relevance in the field of crystal engineering or for the uptake of small molecules for long-term use in energy storage and materials chemistry.UKRI Future Leaders Fellowship [MR/S035486/2], the Royal Society of Chemistry Research Grant [RF19-4013], the Royal Society Research Grant [RGS/R1/231242], the Leverhulme Trust Research Project Grant [RPG-2022-118
Examining inclusivity: the use of AI and diverse populations in health and social care: a systematic review
No full textYesBackground
Artificial intelligence (AI)-based systems are being rapidly integrated into the fields of health and social care. Although such systems can substantially improve the provision of care, diverse and marginalized populations are often incorrectly or insufficiently represented within these systems. This review aims to assess the influence of AI on health and social care among these populations, particularly with regard to issues related to inclusivity and regulatory concerns.
Methods
We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Six leading databases were searched, and 129 articles were selected for this review in line with predefined eligibility criteria.
Results
This research revealed disparities in AI outcomes, accessibility, and representation among diverse groups due to biased data sources and a lack of representation in training datasets, which can potentially exacerbate inequalities in care delivery for marginalized communities.
Conclusion
AI development practices, legal frameworks, and policies must be reformulated to ensure that AI is applied in an equitable manner. A holistic approach must be used to address disparities, enforce effective regulations, safeguard privacy, promote inclusion and equity, and emphasize rigorous validation
Seismic performance of SFCBs reinforced UHPC-filled steel tube composite columns: Test, modeling and theoretical analysis
No full textYesThis paper explores the seismic behavior of a novel composite column, specifically designed to address the issues of rapid stiffness degradation and significant residual deformation that commonly occur in conventional concrete-filled steel tube (CFST) columns under low cycle reversed loading. The proposed composite column comprises of ultra-high performance concrete (UHPC) filled steel tubes (UHPCFST) reinforced with steel-FRP composite bars (SFCBs), which collectively enhance the structural performance under low reversed cyclic loading. The seismic performance of SFCBs-UHPCFST composite columns was investigated by conducting low-cyclic reversed loading tests and finite element modeling, analyzing the effects of strength of concrete and steel tube, type of longitudinal reinforcement, axial compression ratio, slenderness ratio, ratio of longitudinal bars and stirrups. The results indicated that all composite columns exhibited compression-bending failure. Compared with conventional steel-reinforced UHPCFST columns, SFCBs reinforced columns showed slightly lower bearing capacity but demonstrated superior deformation capacity, lower residual deformations, higher energy dissipation capacity, smaller degradation of stiffness and bearing capacity, and better reparability. Increasing concrete strength, reinforcement ratio, or steel yield strength, or reducing the slenderness ratio effectively enhanced the loading capacity and initial stiffness of SFCBs-UHPCFST composite columns, while increasing the stirrup ratio had a limited effect. With the axial compression ratio improved from 0.15 to 0.25, the bearing capacity of SFCBs-UHPCFST composite columns increased; however, when the ratio improved from 0.25 to 0.35 and 0.45, the bearing capacity significantly reduced, second-order P-Δ effects became more pronounced, and the stiffness degradation rate increased. Finally, a hysteretic model for the SFCBs-UHPCFST composite columns was established based on a degraded trilinear model, with predicted values fitting well with experimental results, accurately reflecting the hysteretic behavior of SFCBs-UHPCFST composite columns.National Natural Science Foundation of China (51678514), High-End Foreign Experts Project of Ministry of Science and Technology, China (G2022014054L), Science and Technology Project of Jiangsu Construction System (2023ZD104, 2023ZD105), Yangzhou City and Yangzhou University Science and Technology Cooperation Fund Project (YZ2022194), Graduate Research and Innovation Projects of Jiangsu Province (KYCX24_3750), Jiangsu Provincial Government Scholarship Project (2024), Excellent Doctoral Dissertation Fund of Yangzhou University (2024)The full-text of this article will be released for public view at the end of the publisher embargo on 15 Feb 2027
Developing electrothermal energy storage system for building heating by using stainless steel wires reinforced ultra-high performance concrete
No full textYesStainless steel wires (SSWs) with microscale diameter and high aspect ratio can form extensive electrically and thermally conductive networks within concrete at low contents. Combined with their high mechanical properties and corrosion resistance, SSWs enable concrete with self-heating capability and excellent thermal conductivity, as well as ultra-high mechanical properties and durability. Such SSWs enabled self-heating ultra-high performance concrete (SES-UHPC) can achieve active temperature control and on-site utilization of intermittent renewable energies, beneficial to reducing energy consumption and carbon emissions from building heating. Therefore, this study prepared SES-UHPC slabs embedded with Al2O3 tubes encapsulating either water or phase change material (PCM). The content levels of SSWs incorporated in test specimens were 0.5 vol.%, 1.0 vol.%, and 1.5 vol.%. The electrical, self-heating, and thermal storage properties as well as the thermal storing-releasing model of these slabs were investigated. Furthermore, their building heating performances were verified in a simulated room. The results indicated that the SES-UHPC slab with 1.5 vol.% of SSWs has an electrical conductivity as low as 2.0 Ω·cm, unaffected by temperature and thermal cycling. The slab with 1.5 vol.% of SSWs can be heated from 20°C to 80°C with a power of 65 W in 6.8 h, and it continuously provides a total of 90.5 kJ heat supply for 14.4 h. The proposed thermal storing-releasing model based on Newton's law of cooling can accurately describe the temperature of the slabs tested. In a simulated room, the SES-UHPC slabs with water/PCM kept the indoor temperature above 15°C for 14.4 h to 10.3 h with outdoor temperatures of -5°C to -3°C and wind speed of up to 5.7 m/s.National Science Foundation of China (52308236, 52308243, and 52368031), the Fundamental Research Funds for the Central Universities (DUT24GJ202), and the Major Science and Technology Research Project of the China Building Materials Federation (2023JBGS10-02).The full-text of this article will be released for public view at the end of the publisher embargo on 27 Feb 2027
Deploying Artificial Intelligence in Preserving Data Security in Cyber Warfare
No full textNoThe emergence of new technologies has changed the landscape of cyber operations worldwide. Cyberspace has been identified as the fifth dimension after land, sea, air and space where warfare against nation-states occurs. Cyber-attacks on a nation’s critical infrastructure have the capacity to immobilize a state which includes total system failure due to the infiltration of data. If one sector fails, it would cause a domino effect on other critical sectors which could result in a national catastrophe. Cyber threats are complex, destructive and coercive ranging from low-level to technologically sophisticated attacks. The surge of artificial intelligence has created an era of uncertainties and vulnerabilities as it led to political instability and power rivalry. Such technologies have expanded the commission of cyber warfare where nation-states began to focus on protecting critical national infrastructure that requires cyber protection and security. Cyber warfare via modern technologies includes algorithmic dissemination of information, cyberattacks and social media manipulation. In response, States are using new technologies by deploying data analytics and machine learning in detecting and responding to cyber threats. Artificial intelligence also has the capability to improve in reconnaissance and social engineering which makes threat detection more effective and efficient. Data securitisation is critical due to the sensitivity and impact of such proliferation, which would compromise a nation's political, technological and military capacity and its citizens. The digitisation of various sectors has made available such information that opponents would have the digital means to destroy critical sectors, obtain confidential information and disrupt operations. Data security has become an integral part of modern warfare with the influx of disinformation, including information used in complex digital battles. The securitisation of data includes protecting physical and digital data from misuse, disclosure, unauthorised access, unlawful modification and deletion. The consequences would include disruption of critical services, financial loss, privacy issues and data confidentiality. This paper will discuss the current legal landscape in governing data security within the context of cyber warfare and the impact of artificial intelligence in the preservation of data amid the challenging global environment. The element of secrecy and concealment provided in cyberspace made the detection and prevention difficult. The effect of poor data security will not only impact national security but would also cause societal changes where the division of society, public outrage and undermining of trust in the government could happen. Such considerations have driven nation-states to prioritise cybersecurity as it has become an essential element for geopolitical relations where countries compete for advantage and influence within cyberspace
How to navigate and ensure effective patient communication about medicines shortages
No full textNoBest practice principles on gathering information to inform communications, information sharing with patients and working across boundaries to better support affected patients during medicines shortages
Veterans join Pacific Islanders in bid for nuclear testing compensation
No full textNoThe health challenges of Kiritimati people remain largely forgotten, despite records showing that 189 families became unwell after the tests