Developing reduced-order models for the transport of solid particles in turbulence typically requires a statistical description of the particle–turbulence interactions. In this work, we utilize a statistical framework to derive continuum equations for the moments of the slip velocity of inertial, settling Lagrangian particles in a turbulent boundary layer. Using coupled Eulerian–Lagrangian direct numerical simulations, we then identify the dominant mechanisms controlling the slip velocity variance, and find that for a range of Stokes number ${S{\kern-0.5pt}t}^+$, Settling number ${S{\kern-0.5pt}v}^+$ and Reynolds number $\textit{Re}_\tau$ (based on frictional scales),the slip variance is primarily controlled by local differences between the ‘seen’ variance and the particle velocity variance, while terms appearing due to the inhomogeneity of the turbulence are subleading until ${S{\kern-0.5pt}v}^+$ becomes large. We also consider several comparative metrics to assess the relative magnitudes of the fluctuating slip velocity and the mean slip velocity, and we find that the vertical mean slip increases rapidly with ${S{\kern-0.5pt}v}^+$, rendering the variance relatively small – an effect found to be most substantial for ${S{\kern-0.5pt}v}^+\gt 1$. Finally, we compare the results with a model of the acceleration variance (Berk & Coletti 2021 J. Fluid Mech. 917, A47) based the concept of a response function described in Csanady (1963 J. Atmos. Sci. 20, 201–208), highlighting the role of the crossing trajectories mechanism. We find that while there is good agreement for low ${S{\kern-0.5pt}v}^+$, systematic errors remain, possibly due to implicit non-local effects arising from rapid particle settling and inhomogeneous turbulence. We conclude with a discussion of the implications of this work for modelling the transport of coarse dust grains in the atmospheric surface layer.

Ewe and Guin-Mina people in Togo often use festival and ritual events as forums for cultural exchange and as opportunities to reinterpret and repurpose images and objects imported from India. Instead of focusing on large-scale commercial interactions, this article illustrates Afro-Indian cultural exchanges enacted microcosmically upon the canvas of West African bodies. I examine small-scale encounters between Ewe and Guin-Mina Vodun practitioners and South Asian merchants, paying close attention to ritual performances for Mami Wata – a pantheon of Pan-African water spirits often depicted as mermaids and venerated for their dominion over maritime trade. Specifically, I consider how ritual specialists devoted to Mami Wata index histories of trade with Indian merchants through performances that embody Hindu chromolithograph images of deities like Dattatreya and Shiva as depictions of local water spirits. Focusing on movements, gestures and transoceanic flows of currency, goods and objects present in Togolese Mami Wata veneration, this article teases out the threads of critical consumerism, gender fluidity and choreographic practices that accompany such ceremonies, especially during moments of transformative copresence with spirits. Exploring ways Ewe and Guin-Mina performers in Togo use stylized gestures and adornments to transform understandings of commercial relations with foreigners into sources of agency and transformation, I examine ritual choreographies in public festivals and private rituals as oceanic intersections: material representations of desires for social, transcultural and transnational mobility.

An adverse in utero experience negatively impacts perinatal growth in livestock. Maternal heat stress (HS) during gestation reduces placental growth and function. This progressive placental insufficiency ultimately leads to fetal growth restriction (FGR). Studies in chronically catheterized fetal sheep have shown that FGR fetuses exhibit hypoxemia, hypoglycemia, and lower anabolic hormone concentrations. Under hypoxic stress and nutrient deficiency, fetuses prioritize basal metabolic requirements over tissue accretion to support survival. Skeletal muscle is particularly vulnerable to HS-induced placental insufficiency due to its high energy demands and large contribution to total body mass. In FGR fetuses, skeletal muscle growth is reduced, evidenced by smaller myofiber size and mass, reduced satellite cell proliferation, and slower rate of protein synthesis. Disruptions in skeletal muscle growth are associated with mitochondrial dysfunction, including reduced pyruvate flux into the mitochondrial matrix and lower complex I activity in the mitochondrial electron transport chain. This review summarizes current research on the mechanisms by which HS-induced placental insufficiency affects skeletal muscle growth in the fetus, with an emphasis on myogenesis, hypertrophy, protein synthesis, and energy metabolism. The evidence presented is primarily drawn from experiments using chronically catheterized fetal sheep exposed to maternal HS during mid-gestation. Additionally, we explore emerging nutritional strategies aimed at enhancing skeletal muscle growth in animals with FGR. These strategies hold promise not only for improving reproductive efficiency in livestock affected by prenatal stress but also for their translational relevance to human pregnancies complicated by placental insufficiency.

This article examines why, beginning in 1946, the Brazilian government under President Eurico Dutra supplied arms to Dominican dictator Rafael Trujillo, fuelling a regional arms race and reshaping Caribbean Basin dynamics at the onset of the Cold War. It argues that these transfers bypassed conventional diplomatic channels, reflected radical anti-communist currents within Dutra’s inner circle and undercut US non-proliferation efforts. Far from a passive ally, Brazil emerged as a pivotal, if under-recognised, actor in the continental polarisation that led to democratic collapse in Venezuela (1948), Cuba (1952) and Guatemala (1954). The article challenges assumptions of Brazil’s limited Latin American engagement and repositions Dutra’s foreign policy within broader continental strategies of ideological alignment and regional influence. Drawing on Brazilian diplomatic and press sources, as well as archival and printed materials from across Latin America, Europe and the United States, it addresses historiographical gaps around Dutra’s agency and reveals the material underpinnings of Trujillo’s aggression, contributing to a revised understanding of Brazil’s Cold War trajectory.

Powerful lasers may be used in the future to produce magnetic fields that would allow us to study turbulent magnetohydrodynamic inverse cascade behaviour. This has so far only been seen in numerical simulations. In the laboratory, however, the produced fields may be highly anisotropic. Here, we present corresponding simulations to show that, during the turbulent decay, such a magnetic field undergoes spontaneous isotropisation. As a consequence, we find the decay dynamics to be similar to that in isotropic turbulence. We also find that an initially pointwise non-helical magnetic field is unstable and develops magnetic helicity fluctuations that can be quantified by the Hosking integral. It is a conserved quantity that characterises magnetic helicity fluctuations and governs the turbulent decay when the mean magnetic helicity vanishes. As in earlier work, the ratio of the magnetic decay time to the Alfvén time is found to be approximately $50$ in the helical and non-helical cases. At intermediate times, the ratio can even reach a hundred. This ratio determines the endpoints of cosmological magnetic field evolution.

Recent years have witnessed a “juridical turn” in Chinese environmental governance, emphasising and encouraging legal mobilisation and litigation deployment by citizens to address environmental grievances in either individual or collective forms. This legalisation movement has spawned a budding, socio-legal field of Chinese environmental justice (CEJ), with an ostensible trend towards the legal empowerment of community organisations as “autonomous” litigants representing public interests. Drawing on extensive qualitative data, this study examines how plural, fluid state–society relations are manifested, animated, and permeated in the interactive processes of the CEJ. The analysis reveals four emergent modes of political–organisational connections—the state’s challengers, allies, servants, and subordinates—all of which depend on how the Chinese state interprets their motives for using the law and engaging in litigations, and anticipated effects their legal mobilisation can generate or diffuse in society. The bounded community mobilisation within the CEJ has also embodied the continuing state supremacy and the growing legal responsiveness in the Chinese approach to modernisation. Future theoretical and policy implications for the participatory effectiveness of community organisations in the CEJ are also discussed.

Mass street protests and other highly contentious actions often capture headlines and public attention, but what remains after the news cycle moves on? Many times, grassroots initiatives crystallise during or after these intense moments of participation, leaving in their wake effective organisations that continue to make daily life more liveable in contexts of extreme vulnerability. Despite the persistence and impact of these ‘things that work’ – as we call them – they are often less visible and understudied. How do these initiatives emerge and sustain themselves in the communities in which they work? Using ethnographic methods, we investigate the case of a community centre formed in the wake of a land occupation in the urban periphery of Buenos Aires to answer these questions. We argue that grassroots initiatives build local power through everyday care-work: forming relationships, changing identities and providing valuable services and information.

Tax collection is difficult in low-income countries, and bureaucracies exist alongside non-state actors that extract revenue and provide services informally. Might weak states leverage these actors’ strengths to collect taxes, or should they invest in building fiscal capacity on their own? We conducted a field experiment in Lagos, Nigeria that randomly assigned market vendors to tax appeals delivered by state or non-state agents. Contrary to expectations, non-state actors were not effective messengers. Tax appeals delivered by representatives of marketplace associations, an important social intermediary in this context, were ineffective even at higher levels of trust and message credibility. Messages delivered by state agents, however, were sometimes effective in spurring registration and tax payments, especially among ethnic minorities. This study underlines the importance of social intermediaries in shaping the social contract, and it draws attention to the uneven effects of these kinds of institutions within populations.

We describe a training series using a scaffolded approach informed by Vygotsky’s Learning Theory to advance Hawai‘i -based faculty grant-writing skills. Sponsored by the Professional Development Core of the Center for Pacific Innovations, Knowledge, and Opportunities (PIKO) at the University of Hawai‘i at Mānoa, the initiative includes a 2-week series of 1-hour introductory sessions on aspects of grant writing, a 3-session workshop to develop a specific aims page, and a 5-month training program in grant writing. Over three years, 202 Hawai‘i investigators attended at least one 1-hour introductory session, 62 completed the workshop on preparing specific aims, and 30 completed the 5-month training on grant writing. Participants rated all 3 programs as very useful. Of the 62 unique investigators who completed the Specific Aims Workshop, 21 (33%) submitted PIKO pilot grant applications, 4 (6%) submitted grants elsewhere, and 16 (30%) applied to the 5-month training on grant writing. The 30 GUMSHOE participants reported significant gains in their confidence in accomplishing 21 proposal-writing tasks and, as of May 2025, 26 (87%) submitted grants to the National Institutes of Health or another external funder. This scaffolded training approach is labor- and time-intensive for trainees and faculty mentors, but our outcomes demonstrate its success.