Research disruption during PhD studies and its impact on mental health: Implications for research and university policy

Research policy observers are increasingly concerned about the impact of the disruption caused by the Covid-19 pandemic on university research. Yet we know little about the effect of this disruption, specifically on PhD students, their mental health, and their research progress. This study drew from survey responses of UK PhD students during the Covid-19 pandemic. We explored evidence of depression and coping behaviour (N = 1780), and assessed factors relating to demographics, PhD characteristics, Covid-19-associated personal circumstances, and significant life events that could explain PhD student depression during the research disruption (N = 1433). The majority of the study population (86%) reported a negative effect on their research progress during the pandemic. Results based on eight mental health symptoms (PHQ-8) showed that three in four PhD students experienced significant depression. Live-in children and lack of funding were among the most significant factors associated with developing depression. Engaging in approach coping behaviours (i.e., those alleviating the problem directly) related to lower levels of depression. By assessing the impact of research disruption on the UK PhD researcher community, our findings indicate policies to manage short-term risks but also build resilience in academic communities against current and future disruptions

Market microstructure issues related to the Greek capital market

Since the stock market crash of October 1987, academics and policy makers have been very concerned about the causes of the crash and whether the microstructure of the equity market should be redesigned to protect the market from drastic fluctuations. For their concerns, circuit breakers have been recommended as the mechanisms for the market stabilisation and for reducing the volatility of the stock market. Empirical and theoretical studies carried out so far have not been able to conclusively resolve the debate on the effects of circuit breakers on financial markets. As a result, this thesis aims to contribute to the market microstructure literature and to add empirical content to current academic and policy discussions, by conducting an investigation on the effects and implications of circuit breakers on financial markets, focusing on daily price limits, transaction taxes and margin requirements, with specific reference to the Greek capital market. Based on our empirical findings, we provide little evidence in support of the effectiveness of the above regulatory measures, in line with previous literature. Furthermore, our empirical findings suggest that both researchers and policy makers. should continue their efforts to conduct further tests on their suitability, as well as in exploring other mechanisms and channels, which might be more effective in stabilising the market and reducing volatility. Finally, the empirical findings in this thesis support what Roll (1989) stated over 17 years ago in his comprehensive review on the implications for regulatory policy. that there is little evidence in favour of the efficacy of margin requirements, price limits and transaction taxes

Optimal planning of distribution grids considering active power curtailment and reactive power control

In this paper, a new planning methodology is proposed for existing distribution grids, considering both passive and active network measures. The method is designed to be tractable for large grids of any type, e.g., meshed or radial. It can be used as a decision-making tool by distribution system operators which need to decide whether to invest in new hardware, such as new lines and transformers, or to initiate control measures influencing the operational costs. In this paper, active power curtailment and reactive power control are taken into account as measures to prevent unacceptable voltage rises as well as element overloads, as these allow postponing network investments. A low-voltage, meshed grid with 27 nodes is used to demonstrate the proposed scheme. In this particular case, the results show that by using control measures, an active distribution system operator can defer investments and operate the existing infrastructure more efficiently. The methodology is able to account for variations in operational and investment costs coming from regulatory influences to provide an insight to the most cost-efficient decision

Coordinating service provision in dynamic service settings: a position practice relations perspective

How is continuity of service provision supported in dynamic service settings (DSS) when interactions span space and time, and are being increasingly infused by technology? We explored this question through our eighteen-month qualitative study of the DSS of UK mental health. We found that the pattern of interaction that emerges is constantly reconfigured through processes of spanning time, stretching space and through distributed agency. Further, we found that service provision does not only occur among work roles with clear (cross)organizational links but also through diverse interaction among current customers and their friends, as well as customer-to-customer interactions. We characterize such service provision which is not anchored to any service organization as being extraorgnizational. Further, we highlight the importance of the history of interactions and how trust built through diverse interactions in the past may influence trust building in current interaction. To explain our findings we introduce the concepts of "position-practices" and position-practice relations (PPR) to theorize how diverse interaction among dispersed actors contributes to service provision continuity in DSS. We develop a conceptual process model which identifies processes of spanning time, and the stretching of space by which the PPR web of service provision is dynamically reconfigured, and with what consequences for both our case as well as other dynamic service settings.We acknowledge the support of the National Institute of Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care (CLAHRC) East of England. The first author is also grateful to the Alexander S. Onassis Public Benefit Foundation for funding her doctoral studies and was funded during the development of this manuscript by the NIHR Collaboration for Leadership in Applied Health Research and Care Oxford at Oxford Health NHS Foundation Trust

A Data-Driven Two-Stage Distributionally Robust Planning Tool for Sustainable Microgrids

This paper presents a data-driven two-stage distributionally robust planning tool for sustainable microgrids under the uncertainty of load and power generation of renewable energy sources (RES) during the planning horizon. In the proposed two-stage planning tool, the first-stage investment variables are considered as here-and-now decisions and the second-stage operation variables are considered as wait-and-see decisions. In practice, it is hard to obtain the true probability distribution of the uncertain parameters. Therefore, a Wasserstein metric-based ambiguity set is presented in this paper to characterize the uncertainty of load and power generation of RES without any presumption on their true probability distributions. In the proposed data-driven ambiguity set, the empirical distributions of historical load and power generation of RES are considered as the center of the Wasserstein ball. Since the proposed distributionally robust planning tool is intractable and it cannot be solved directly, duality theory is used to come up with a tractable mixed-integer linear (MILP) counterpart. The proposed model is tested on a 33-bus distribution network and its effectiveness is showcased under different conditions

Comparison of AC Optimal Power Flow Methods in Low-Voltage Distribution Networks

Embedded with producers, consumers, and prosumers, active Low-Voltage Distribution Networks (LVDNs) with bi-directional power flows are rising to over-shadow the investment and operation planning in power systems. The Optimal Power Flow (OPF) has been extensively used in the recent years to solve different investment and operation planning problems in LVDNs. However, OPF is inherently a complex non-linear and non-convex optimization problem. Hence, different linearization and convexification models have been introduced in the literature to enhance the modeling accuracy and computational tractability of the OPF problem in LVDNs. In this paper, five multi-period OPF models (including the basic non-linear and non-convex one) are presented, with different linearizations/convexifications for the power flow equations. The proposed models are implemented on the IEEE 34-bus test system and their modeling accuracy and computational complexity are compared and discussed

mHealth and global mental health: still waiting for the mH2 wedding?

Background Two phenomena have become increasingly visible over the past decade: the significant global burden of disease arising from mental illness and the rapid acceleration of mobile phone usage in poorer countries. Mental ill-health accounts for a significant proportion of global disability-adjusted life years (DALYs) and years lived with disability (YLDs), especially in poorer countries where a number of factors combine to exacerbate issues of undertreatment. Yet poorer countries have also witnessed significant investments in, and dramatic expansions of, mobile coverage and usage over the past decade. Debate The conjunction of high levels of mental illness and high levels of mobile phone usage in poorer countries highlights the potential for “mH2” interventions – i.e. mHealth (mobile technology-based) mental health interventions - to tackle global mental health challenges. However, global mental health movements and initiatives have yet to engage fully with this potential, partly because of scepticism towards technological solutions in general and partly because existing mH2 projects in mental health have often taken place in a fragmented, narrowly-focused, and small-scale manner. We argue for a deeper and more sustained engagement with mobile phone technology in the global mental health context, and outline the possible shape of an integrated mH2 platform for the diagnosis, treatment, and monitoring of mental health. Summary Existing and developing mH2 technologies represent an underutilised resource in global mental health. If development, evaluation, and implementation challenges are overcome, an integrated mH2 platform would make significant contributions to mental healthcare in multiple settings and contexts

Light and oxygen induced degradation limits the operational stability of methylammonium lead triiodide perovskite solar cells

Here, we demonstrate that light and oxygen-induced degradation is the main reason for the low operational stability of methylammonium lead triiodide (MeNH3PbI3) perovskite solar cells exposed to ambient conditions. When exposed to both light and dry air, unencapsulated MeNH3PbI3 solar cells rapidly degrade on timescales of minutes to a few hours. This rapid degradation is also observed under electrically bias driven current flow in the dark in the presence of O2. In contrast, significantly slower degradation is observed when the MeNH3PbI3 devices are exposed to moisture alone (e.g. 85% relative humidity in N2). We show that this light and oxygen induced degradation can be slowed down by the use of interlayers that are able to remove electrons from the perovskite film before they can react with oxygen to form O2−. These observations demonstrate that the operational stability of electronic and optoelectronic devices that exploit the electron transporting properties of MeNH3PbI3 will be critically dependent upon the use of suitable barrier layers and device configurations to mitigate the oxygen sensitivity of this remarkable material