Synthesis and Surface functionalisation of TiO2 nanoparticles - Development of versatile colloidal formulations for the fabrication of photocatalytic self-cleaning glass

The aim of this thesis is the synthesis of TiO2 nanoparticles and the study on the formulation of their colloidal form to prepare wet precursors for the fabrication of self-cleaning glasses. The thesis considers the need to find an alternative synthetic route to a classic two-step sol-gel/solvothermal process that is solvent extensive (high carbon footprint) and requires the use of an autoclave to get a crystalline product. In this study, the synthesis of TiO2 nanoparticles was performed by the forced hydrolysis of TiCl4* 2THF in water at 80°C and Patm, which was a one step, low carbon footprint and relative low temperature process. By this method it was possible to obtain highly crystalline (77% of polycrystalline content), mainly anatase (82% of the crystalline content), faceted and 6±2 nm in size nanoparticles, as shown by X-ray Diffractometry (XRD) and Transmission Electron Microscopy (TEM) analysis. According to Thermogravimetric Analysis (TGA), the nanopowders exhibited 10% by weight of chemisorbed water, which is directly linked with a high number of surface -OH groups. Other properties of the TiO2 nanoparticles were the high Brunauer-Emmett-Teller (BET) surface area of 202 m2/g and the band gap of 3.43 eV, deduced by UltraViolet-Visible (UV-Vis) spectroscopy. All these features made the as-synthesized TiO2 nanoparticles suitable for photocatalytic applications. In this study the TiO2 nanoparticles, in their colloidal form, were used as wet precursors to fabricate self-cleaning glasses. Before their deposition on glass, the TiO2 colloids were analyzed by Zeta potential and DLS, showing that in their synthetic liquor they were stable, but exhibited an agglomeration trend with clusters of particles mainly of 20 nm and up to 100 nm. To deagglomerate the nanoparticles, the chosen dispersant was oxalic acid, which is a small natural molecule easy to be degraded, for instance by photolysis under UV light exposure (in the 200-300 nm range). An optimized wet precursor, suitable for the deposition of TiO2 thin films on glass substrates, was formulated as follows: TiO2 1.25*10-2 M in 70% water and 30% Isopropyl alcohol (IPA), pH= 1.30 and oxalic acid 5*10-4 M. This wet precursor was deposited on glass slides by drop casting. To get compact films the nano-TiO2/glass composites were annealed by heat in the temperature range 60-500°C or by a UV curing system (684mW/cm2) at exposure time from 3s to 3 min, that is an alternative to much more energy consuming heat processing. Their photocatalytic activity was assessed by stearic acid degradation under UV light exposure and compared with a commercial self-cleaning glass (ActivTM) and TiO2/glass samples obtained through ALD and spray pyrolysis. The results, reported in terms of Formal Quantum Efficiency (FQE), demonstrated that all the nano-TiO2/glass samples have a much higher self-cleaning property than ActivTM glass and samples prepared by other techniques that do not employ nanoparticles. The photocatalytic properties of TiO2 nanocolloids were also extended to other substrates, so that the last part of this thesis presents a study to make them compatible with metal substrates. The main problem of this study was the strong acidity of the TiO2 nanocolloids liquor that corrodes metal surfaces, hence a change in their formulation was needed. The increase of the pH to a neutral range by the mean of an alkaline solution (NaOH or NH4OH) led to precipitation. The alternative approach to reduce the acidity of the TiO2 colloids is represented by transferring the TiO2 nanoparticles from their liquor to another solvent, while keeping their stability. This was achieved in 2-butanol using hexanoic acid as a carrier molecule, that is a sustainable chemical compared to surfactants normally employed for nanoparticles surface modification. The resultant colloids were tested on two different metal substrates provided by Tata Steel, Electrolytic Chromium Coated Steel (ECCS) and Trivalent Chromium-Coating Technology (TCCT),on which no signs of corrosion were evident

Prevalence and severity of frailty amongst middle-aged and older adults conveyed to hospital by ambulance between 2010 and 2017 in Wales

Background: Ambulance services are commonly used by older adults. The scope of services continues to adapt in response to more non–life-threatening calls, often due to the acute consequences of chronic illness. Frailty increases with increasing age, but it is not known how common or severe it is within patients conveyed to hospital by ambulance. Methods: Open cohort of people aged ≥50 living in Wales between 2010 and 2017. Routinely collected electronic data on ambulance attendances resulting in conveyance were linked to primary care data within the Secure Anonymised Information Linkage databank, and the electronic Frailty Index was calculated. The prevalence and severity of frailty according to patient and incident characteristics was described. Results: Of 1 264 094 individuals within the cohort, 23.8% were taken to hospital between 2010 and 2017, of which frailty was present in 84.3% of patients. There was an upward trend in the number of conveyances for patients with moderate and severe frailty across the years in all age groups. The distribution of frailty was similar across call categories, deprivation quintiles and out-of-hours incidents. Patients conveyed from residential homes had a higher level of frailty and comprised 8.7% of the total conveyances. Conclusions: The high prevalence of frailty within adults aged ≥50 with emergency conveyances suggests upskilling ambulance crews with frailty training to enhance their assessment and decision making may improve patient outcomes. The high proportion of conveyances from residential homes indicates scope for increasing integration of community services to provide more patient-centred care pathways

Ideology and the question of agency in Africa’s international relations: the case of Ghana

This article reconceptualises the role of ideology in shaping African agency in international relations, offering a nuanced perspective on how African governments navigate global in(ter)dependence. Responding to calls for more substantive engagement with African agency, it decisively moves beyond established narratives of resistance to highlight a more complex and dynamic understanding of agency. By theorising the interlinkages between ideology and foreign policy, the article demonstrates that African states are not passive actors but strategic agents who contest conventional African ideas, resist external pressures, and selectively embrace external policies aligned with the distinctive ideological orientations of successive governments. Through an analysis of Ghana’s foreign policy under the Nkrumah, Rawlings, and Kufuor administrations  –  ­focusing on regional integration and economic diplomacy – the article generates conceptual bases for understanding small-state behavior in the international system. These insights not only reshape scholarly debates on Africa’s global engagement but also have broader implications for rethinking Global South agency and the accountability of African governments in foreign policymaking. The article thus advances intellectual agendas both within African international relations and the larger discipline, with the potential to influence future research and policy analysis well beyond the Ghanaian case

Flags

These Keywords come out of the research exchange projectAffective Noise: Atmospherics of the State of the Nation betweenthe NOVA University of Lisbon (ICNOVA-FCSH) and Queen MaryUniversity of London. They emerged during two workshops heldin London (QMUL‚ 25-26 October 2024) and in Lisbon (UNL‚ 15-16November 2024)‚ gathering artists‚ researchers and postgraduatestudents interested in how sonic and affective atmospheresshape the current political and theatrical present

‘Our training didn't prepare us for private practice’: A multi‐method study of dietetics graduates' preparedness for private practice employment

Aim: This multi‐method study explored dietetics graduates' preparedness for the landscape of private practice employment. Methods: Qualitative, in‐depth interview and audio‐diary data were collected longitudinally in 2019 regarding dietetics graduates' experiences of private practice employability. Framework analysis of qualitative data prompted a quantitative survey of university representatives in 2021–2022 on the use of private practice placements. Survey data were analysed descriptively. Qualitative themes were reviewed alongside quantitative findings and were interpreted in the context of the sociocultural theory, landscapes of practice. Results: Qualitative data from nine dietetics graduates (total 12 hours of audio data) indicated unpreparedness for this setting, with the following themes identified: 1) private practice skills were lacking; 2) making a living from private practice was challenging; and 3) support was needed. Quantitative data from 18 program directors of accredited universities (100% response) illustrated that private practice placement experiences varied from <10 to 40 days. Placements were most commonly elective (44%) and were not offered by four programs (22%). University program directors expressed concerns that private practice placements were challenging to organise and offered limited client contact hours. Conclusions: It is an educational priority to prepare graduates for available employment opportunities by providing learning experiences that traverse the dietetics landscape of practice. Co‐designing placements with private practice business owners may support authentic experiences of appropriate durations, with ample opportunities for students to build skills to enhance preparedness for this growing employment setting

Enhancing Damping in Single-Phase Grid-Forming Virtual Oscillator Control Inverters: A Feedforward Strategy

The expansion of residential distributed generation systems relies heavily on single-phase inverters for grid integration. However, these inverter-based resources compromise grid stability, mainly due to a lack of inertia and grid strength. To address these issues, grid-forming inverters have been developed, with virtual oscillator control (VOC) emerging as a promising approach due to its superior dynamic performance. However, basic VOC-based inverters cannot provide inertial functionality. Attempts to incorporate virtual inertia into VOCs have significantly reduced the damping factor and led to severe dynamic oscillations. This paper presents a novel technique to improve the dynamic response of single-phase VOC-based inverters by enhancing damping without affecting the virtual inertia and droop functionalities. The effectiveness of the proposed approach is validated through small-signal analysis and extensive experimental testing on a 2.5 kVA single-phase inverter. The results confirm the small-signal model with well-damped dynamic responses in gridconnected mode, without degrading system inertia during stand-alone operation

The role of plasmalogen lipids in synaptic assembly and function: Implications for neurodegenerative processes

Synaptic dysfunction is a hallmark of neurodegeneration and often precedes neuronal death. Plasmalogen lipids, abundant in the brain, have a unique conical structure that supports vesicle fusion and fission, processes essential for synaptic transmission. Declining plasmalogen levels are observed with normal aging and are further exacerbated in Alzheimer’s disease (AD), particularly in carriers of the apolipoprotein E4 (APOE4) allele, the strongest genetic risk factor for late-onset AD.However, the precise role of plasmalogens in neuronal function and neurodegeneration remains unclear. This thesis aimed to elucidate the role of plasmalogens in synaptic assembly, neuronal differentiation, and their potential involvement in reactive oxygen species (ROS)-driven neuroinflammatory processes.To explore the functional significance of plasmalogens, SH-SY5Y cells with silenced fatty acyl CoA reductase 1 (FAR1), the rate-limitng enzyme in plasmalogen biosynthesis, were differentiated into neuron-like cells and assessed for protein expression and synapse assembly. Impaired clustering of the presynaptic protein Synaptophysin 1 in FAR1 knockdown cells revealed a critical role for plasmalogens in synaptic assembly. Further analyses suggested that plasmalogen depletion alters vesicle size, influences ROS degradation, and disrupts early neuronal differentiation, likely impairing cell adhesion.Additionally, this thesis introduces a cost-effective method for generating astrocytelike cells from ReNcell VM progenitors and co-culturing them with iPSC-derived neurons. This innovative approach provides a versatile platform for studying astrocytic lipid trafficking and the impact of APOE, the only lipid transport protein in the human brain and a key genetic risk factor for AD, on neuronal health.In summary, this work underscores the essential role of plasmalogen lipids in neuronal differentiation and synaptic function while establishing valuable methodologies for studying neuron-astrocyte interactions. These findings provide a foundation for future research into the molecular mechanisms of neurodegeneration, aging, and APOE-dependent lipid dysregulation, opening new avenues fortherapeutic strategies

The UK Biobank mental health enhancement 2022: Methods and results

Background: This paper introduces the UK Biobank (UKB) second mental health questionnaire (MHQ2), describes its design, the respondents and some notable findings. UKB is a large cohort study with over 500,000 volunteer participants aged 40-69 years when recruited in 2006-2010. It is an important resource of extensive health, genetic and biomarker data. Enhancements to UKB enrich the data available. MHQ2 is an enhancement designed to enable and facilitate research with psychosocial and mental health aspects. Methods: UKB sent participants a link to MHQ2 by email in October-November 2022. The MHQ2 was designed by a multi-institutional consortium to build on MHQ1. It characterises lifetime depression further, adds data on panic disorder and eating disorders, repeats ‘current’ mental health measures and updates information about social circumstances. It includes established measures, such as the PHQ-9 for current depression and CIDI-SF for lifetime panic, as well as bespoke questions. Algorithms and R code were developed to facilitate analysis. Results: At the time of analysis, MHQ2 results were available for 169,253 UKB participants, of whom 111,275 had also completed the earlier MHQ1. Characteristics of respondents and the whole UKB cohort are compared. The major phenotypes are lifetime: depression (18%); panic disorder (4.0%); a specific eating disorder (2.8%); and bipolar affective disorder I (0.4%). All mental disorders are found less with older age and also seem to be related to selected social factors. In those participants who answered both MHQ1 (2016) and MHQ2 (2022), current mental health measure showed that fewer respondents have harmful alcohol use than in 2016 (relative risk 0.84), but current depression (RR 1.07) and anxiety (RR 0.98) have not fallen, as might have been expected given the relationship with age. We also compare lifetime concepts for test-retest reliability. Conclusions: There are some drawbacks to UKB due to its lack of population representativeness, but where the research question does not depend on this, it offers exceptional resources that any researcher can apply to access. This paper has just scratched the surface of the results from MHQ2 and how this can be combined with other tranches of UKB data, but we predict it will enable many future discoveries about mental health and health in general

Neurodiversity, corporate boards, and corporate performance: A systematic review, evidence-based recommendations and future research agenda

PurposeGlobally, an increasing number of people are not only being medically diagnosed and classified as neurodiverse but also facilitated to participate in economic and social activities, including appointment to corporate boards. The study offers a comprehensive and up-to-date systematic literature review (SLR) of the existing studies on neurodivergent individuals (NDIs), neurodivergent individuals on corporate boards (NDOCBs) and their impact on corporate performance. We seek to synthesise and expand the present understanding of both the existing (1) theoretical foundations and (2) empirical literature on (a) multi-level antecedents of NDIs and NDOCBs and (b) the impacts that NDOCBs have on corporate performance.Design/methodology/approachThe study adopts a three-step SLR method and bibliometric analysis to review one of the most extensive SLR datasets available to date on NDIs and NDOCBs, involving 159 theoretical, quantitative, qualitative and mixed studies undertaken in more than 70 countries from 1976 to 2022.FindingsBased on publications in 118 scholarly journals, we discover that most of the available research is descriptive and/or relies on one theory or none, rather than multi-theoretical views. Second, we find that firm-level antecedents of NDIs and NDOCBs, rather than country-level antecedents, have been the focus of previous research. Third, there are noticeable methodological limitations, such as the scarcity of cross-country, mixed-methods and qualitative studies.Originality/valueThere is little understanding of how neurodiverse people contribute to corporate performance decisions. Synthesis of literature reveals that existing studies examining NDIs and NDOCBs and corporate performance, particularly from an accounting perspective, are rare. Subsequently, we offer an extensive and timely SLR of the existing studies on NDOCBs and corporate performance, highlighting the limitations and discussing the prospects for future research on NDIs and NDOCBs

War and peace: exploring microbial defence systems as a source of new antimicrobial therapies

The WHO has compiled a list of pathogens that urgently require new antibiotics in response to the rising reports of antibiotic resistance and a diminished supply of new antibiotics. At the top of this list is fluoroquinolone-resistant Salmonella typhi, fluoroquinolone-resistant Shigella spp. and vancomycin-resistant Enterococcus faecium. Although these problems have been covered in great detail by other contemporary reviews, there are still some fundamental gaps in the translation of current knowledge of the infectious process and the molecular ecology of antibiotic production into a sustainable protocol for the treatment of pathogenic diseases. Therefore, in this narrative review we briefly discuss newly approved antimicrobial drugs (since 2014) that could help to alleviate the burden of multiresistant pathogens listed on the WHO priority list. Being conscious that such treatments may eventually run the risk of future cycles of resistance, we also discuss how new understandings in the molecular ecology of antibiotic production and the disease process can be harnessed to create a more sustainable solution for the treatment of pathogenic diseases