Almost half of the global population lives with inadequate or unsafe water, sanitation or hygiene (WASH) services. The consequences of this situation include negative impacts on individual and public health, the environment and economic production. The WASH sector is linked with other international development sectors and is embedded within complex social, environmental and governance structures. This complexity led us to reflect on how WASH sector practitioners and researchers are applying systems thinking tools and techniques to progress an agenda of sustainable and universal WASH services. From this perspective, we then discuss the near- and long-term future needs of the sector in coming to a comprehensive understanding and application of systems thinking to progress the ultimate aim of universal access to safely managed, accessible and abundant water, sanitation and hygiene services.

First-of-a-kind engineered systems often burst with complexity – a major cause of project budget and time overruns. Our particular concern is the structural complexity of nuclear fusion devices, which is determined by the amount and entanglement of components. We seek to understand how this complexity rises during the development phase and how to manage it. This paper formulates a theory around the interplay between a problem-solving design process and an evolving design model. The design process introduces new elements that solve problems but also increase the quantifiable complexity of the model. Those elements may lead to new problems, extending the design process. We capture these causal effects in a hierarchy of problems and introduce two metrics of the impact of design decisions on complexity. By combining and incorporating the Function-Behavior-Structure (FBS) paradigm, we create a new problem-solving method. This method frames formulation, synthesis and analysis activities as transitions from problems to solutions. We demonstrate our method for a nuclear fusion measurement system. Exploring different design trajectories leads to alternative design models with varying degrees of complexity. Furthermore, we visualize the time-evolution of complexity during the design process. Analysis of individual design decisions emphasizes the high impact of early design decisions on the final system complexity.

This article summarises the BJPsych Bulletin 2024 special edition on mental health in criminal justice and correctional settings. The edition considers issues across a range of settings, including police custody, the courts and prisons, as well as considering wider international questions and systems within the field. In this edition, we assert the right of the individual to healthcare services that should be available, accessible, acceptable and of good quality. Psychiatry must play a significant role in shaping this debate as it moves forward.

Several disciplines, such as economics, law, and political science, emphasize the importance of legislative quality, namely well-written legislation. Low-quality legislation cannot be easily implemented because the texts create interpretation problems. To measure the quality of legal texts, we use information from the syntactic and lexical features of their language and apply these measures to a dataset of European Union legislation that contains detailed information on its transposition and decision-making process. We find that syntactic complexity and vagueness are negatively related to member states’ compliance with legislation. The finding on vagueness is robust to controlling for member states’ preferences, administrative resources, length of texts, and discretion. However, the results for syntactic complexity are less robust.

Two asymptotic configurations on a full $\mathbb {Z}^d$-shift are indistinguishable if, for every finite pattern, the associated sets of occurrences in each configuration coincide up to a finitely supported permutation of $\mathbb {Z}^d$. We prove that indistinguishable asymptotic pairs satisfying a ‘flip condition’ are characterized by their pattern complexity on finite connected supports. Furthermore, we prove that uniformly recurrent indistinguishable asymptotic pairs satisfying the flip condition are described by codimension-one (dimension of the internal space) cut and project schemes, which symbolically correspond to multidimensional Sturmian configurations. Together, the two results provide a generalization to $\mathbb {Z}^d$ of the characterization of Sturmian sequences by their factor complexity $n+1$. Many open questions are raised by the current work and are listed in the introduction.

Challenges in implementing digital health in clinical practice hinder its potential. The complexities posed by implementation could benefit from using design practices. To explore the current role of design practices in digital health implementation, designers in the Netherlands were interviewed. The preliminary results indicate that designers contribute to digital health implementation processes, especially in the early stages. Design practices are mainly used for engaging the users, testing concepts, aligning the ideas of stakeholders, and adapting interventions to fit within the contexts.

The aim of this paper is to determine the asymptotic growth rate of the complexity function of cut-and-project sets in the non-abelian case. In the case of model sets of polytopal type in homogeneous two-step nilpotent Lie groups, we can establish that the complexity function asymptotically behaves like $r^{{\mathrm {homdim}}(G) \dim (H)}$. Further, we generalize the concept of acceptance domains to locally compact second countable groups.

Research on visual attention has uncovered significant anomalies, and some traditional methods may have inadvertently probed peripheral vision rather than attention. Vision science needs to rethink visual attention from the ground up. To facilitate this, for a year I banned the word “attention” in my lab. This constraint promoted a more precise discussion of attention-related phenomena, capacity limits, and mechanisms. The insights gained lead me to challenge attributing to “attention” those phenomena that can be better explained by perceptual processes, are predictable by an ideal observer model, or that otherwise may not require an additional mechanism. I enumerate a set of critical phenomena in need of explanation. Finally, I propose a unifying theory in which all perception results from performing a task, and tasks face a limit on complexity.

In the context of the ongoing war in Ukraine, it is striking that there have been many references to resilience, including by Western and Ukrainian leaders. This article is precisely about their use of resilience discourse, and it makes two important contributions to existing scholarship on resilience in conflict settings. First, drawing on Ish-Shalom’s idea of ‘concepts at work’ and analysing a selection of speeches and policy statements (by Western leaders and President Volodymyr Zelensky) that specifically refer to resilience, it demonstrates that resilience is a significant ‘concept at work’ in the war, making certain forms of international and domestic politics possible. Second, while research on resilience frequently discusses different ways that the concept has been defined and approached in fields such as engineering, ecology, and psychology, this article highlights that diverse framings of resilience have become entangled as the concept is ‘at work’ in the war in Ukraine. More specifically, its analysis makes prominent the fusion of different resiliences at different levels – from the individual to the systemic – discursively working together for particular political ends. In this way, it offers a novel way of thinking multi-systemically about resilience and, by extension, about resilience and complexity.