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This paper presents excavation results from Nyabusora, northern Tanzania, conducted by M. Posnansky and W.W. Bishop (1959) and M. Posnansky (1961). Only preliminary reports have previously been published. It synthesises the site’s history, incorporating previously unpublished analyses and information from Posnansky’s original field notes, and presents new 2014 field survey results and new archival research. Nyabusora holds particular significance as the only Early to Middle Stone Age (ESA/MSA) site in the region to have yielded both lithic and faunal remains, which gain new relevance in light of recent developments in ESA/MSA archaeology in eastern Africa. Nyabusora’s ‘Sangoan’ lithic assemblage is now largely decontextualised and associated finds have been lost, so this study presents the only available lithic and faunal analyses, alongside interpretations of the stratigraphic sequence and site. Such stratified assemblages are exceptionally rare and are generally attributed to the Middle Pleistocene. This research enhances understanding of Plio-Pleistocene landscape evolution in the Kagera River and western Lake Victoria-Nyanza Basin. It contributes important new data on ESA/MSA lithic variability and, via ongoing investigations by Basell within the Kagera catchment, offers huge potential for clarifying Middle Pleistocene palaeoenvironments.
Demand currently greatly outweighs supply in teenage mental health, with statutory services and the third sector struggling to cope with the number of referrals. There is increasing interest in the possibility of using schools to provide mental health interventions. This pilot study looked at the feasibility of developing a version of an existing evidence-based transdiagnostic large-class didactic approach widely used in NHS adult services – ‘Stress Control’ – for use with teenagers as a universal early intervention/prevention approach taught by teachers within the Personal and Social Education (PSE) curriculum in a high school in a highly deprived area. PSE teachers were trained, over five hours, to deliver each of the eight sessions in single weekly periods. Measures of anxiety and depression (RCADS) and wellbeing (WEMBWS) were administered at pre- and post-intervention and at 9-month follow-up. Results suggest that teachers reported few problems in delivering the approach, seen as relevant by pupils and showed significant reduction in anxiety and depression and significant gains in wellbeing at post-intervention. These gains were maintained at 9-month follow-up. There appears to be potential in this model. One of its strengths appears to be the positive collaboration between the psychologist, teachers and pupils, which resulted in changes being made to the original model. Limitations of the study and suggestions for future research are given.
Key learning aims
(1) To learn if an evidence-based adult psychoeducational approach can be adapted to meet the needs of teenage pupils in a school in a deprived neighbourhood.
(2) To learn if teachers, with no training in mental health, can deliver this approach.
(3) To test the viability of the approach with an aim of creating a sustainable intervention.
We introduce a natural weighted enumeration of lattice points in a polytope, and give a Brion-type formula for the corresponding generating function. The weighting has combinatorial significance, and its generating function may be viewed as a generalization of the Rogers–Szegő polynomials. It also arises from the geometry of the toric arc scheme associated to the normal fan of the polytope. We show that the asymptotic behaviour of thecoefficients at $q=1$ is Gaussian.
In this paper we are concerned with susceptible–infected–removed (SIR) epidemics with vertex-dependent recovery and infection rates on complete graphs. We show that the hydrodynamic limit of our model is driven by a nonlinear function-valued ordinary differential equation consistent with a mean-field analysis. We further show that the fluctuation of our process is driven by a generalized Ornstein–Uhlenbeck process. A key step in the proofs of the main results is to show that states of different vertices are approximately independent as the population $N\rightarrow+\infty$.
Slip effects on solid boundaries are common in complex fluids. Boundary depletion layers in polymer solutions can create apparent slip effects, which can in turn significantly impact the dynamics of moving bodies. Motivated by microswimmer locomotion in such environments, we derive a series of slip slender-body theories for filamentous bodies experiencing slip-like boundary conditions. Using Navier’s slip model, we derive three slip slender-body theories, linking the body’s velocity to the distribution of hydrodynamic forces. The models are shown to be consistent with each other and with existing numerical computations. As the slip length increases, we show that the drag parallel to the body decreases towards zero while the perpendicular drag remains finite, in a manner which we quantify. This reduction in drag ratio is shown to be inversely related to microswimmer mobility in two simple swimmer models. This increase could help rationalise empirically observed enhanced swimming in complex fluids.
This paper investigates the flow past a flexible splitter plate attached to the rear of a fixed circular cylinder at low Reynolds number 150. A systematic exploration of the plate length ($L/D$), flexibility coefficient ($S^{*}$) and mass ratio ($m^{*}$) reveals new laws and phenomena. The large-amplitude vibration of the structure is attributed to a resonance phenomenon induced by fluid–structure interaction. The modal decomposition indicates that resonance arises from the coupling between the first and second structural modes, where the excitation of the second structural mode plays a critical role. Due to the combined effects of added mass and periodic stiffness variations, the two modes become synchronised, oscillating at the same frequency while maintaining fixed phase difference $\pi /2$. This further results in the resonant frequency being locked at half of the second natural frequency, which is approximately three times the first natural frequency. A reduction in plate length and an increase in mass ratio are both associated with a narrower resonant locking range, while a higher mass ratio also shifts this range towards lower frequencies. A symmetry-breaking bifurcation is observed for cases with $L/D\leqslant 3.5$, whereas for $L/D=4.0$, the flow remains in a steady state with a stationary splitter plate prior to the onset of resonance. For cases with a short flexible plate and a high mass ratio, the shortened resonance interval causes the plate to return to the symmetry-breaking stage after resonance, gradually approaching an equilibrium position determined by the flow field characteristics at high flexibility coefficients.
Although deep reinforcement learning (DRL) techniques have been extensively studied in the field of robotic manipulators, there is limited research on directly mapping the output of policy functions to the joint space of manipulators. This paper proposes a motion planning scheme for redundant manipulators to avoid obstacles based on DRL, considering the actual shapes of obstacles in the environment. This scheme not only accomplishes the path planning task for the end-effector but also enables autonomous obstacle avoidance while obtaining the joint trajectories of the manipulator. First, a reinforcement learning framework based on the joint space is proposed. This framework uses the joint accelerations of the manipulator to calculate the Cartesian coordinates of the end-effector through forward kinematics, thereby performing end-to-end path planning for the end-effector. Second, the distance between all the linkages of the manipulator and irregular obstacles is calculated in real time based on the Gilbert–Johnson–Keerthi distance algorithm. The reward function containing joint acceleration is constructed with this distance to realize the obstacle avoidance task of the redundant manipulator. Finally, simulations and physical experiments were conducted on a 7-degree-of-freedom manipulator, demonstrating that the proposed scheme can generate efficient and collision-free trajectories in environments with irregular obstacles, effectively avoiding collisions.
We analyze nearly 70,000 New York City criminal court arraignments to examine how judges’ professional backgrounds influence pretrial detention. We classify judges as having experience in law enforcement, legal services, both, or neither. Judges with law enforcement backgrounds are, on average, 3.9 percentage points more likely than others to order detention and impose cash bail. When bail is imposed, they set amounts about 32% higher. No significant differences emerge for legal services backgrounds. Because law enforcement experience is common among judges, our findings have broad implications for pretrial detention nationwide.
Here we report microfossil helminth analysis of soils/sediments from the Cloudman site, Lake Huron, Michigan, encompassing the Early Late Woodland (AD 500/600–1000) to the early Historic period. Results reveal eggs of the dog nematode Toxocara canis (a first for North America), the human nematode Ascaris lumbricoides, and a species of taeniid cestode, intestinal parasites that could have affected the health of people and their domesticated dogs. The eggs suggest that the presence of dogs at the site remained relatively stable over the c. 1000-year span of this period. The results offer a new line of evidence for possible dog presence and domestication in North America.
A thin, evaporating sessile droplet with a pinned contact line containing inert particles is considered. In the limit in which the liquid flow decouples from the particle transport, we discuss the interplay between particle advection, diffusion and adsorption onto the solid substrate on which the droplet sits. We perform an asymptotic analysis in the physically relevant regime in which the Péclet number is large, i.e. ${\textit{Pe}}\gg 1$, so that advection dominates diffusion in the droplet except in a boundary layer near the contact line, and in which the ratio of the particle velocities due to substrate adsorption and diffusion is at most of order unity as ${\textit{Pe}}\rightarrow \infty$. We use the asymptotic model alongside numerical simulations to demonstrate that substrate adsorption leads to a different leading-order distribution of particle mass compared with cases with negligible substrate adsorption, with a significant reduction of the mass in the suspension – the nascent coffee ring reported in Moore et al. (J. Fluid Mech., vol. 920, 2021, A54). The redistribution leads to an extension of the validity of the dilute suspension assumption, albeit at the cost of breakdown due to the growth of the deposited layer, which are important considerations for future models that seek to accurately model the porous deposit regions.
In this paper, we study the cohomology of the unitary unramified PEL Rapoport-Zink space of signature $(1,n-1)$ at hyperspecial level. Our method revolves around the spectral sequence associated to the open cover by the analytical tubes of the closed Bruhat-Tits strata in the special fiber, which were constructed by Vollaard and Wedhorn. The cohomology of these strata, which are isomorphic to generalized Deligne-Lusztig varieties, has been computed in an earlier work. This spectral sequence allows us to prove the semisimplicity of the Frobenius action and the non-admissibility of the cohomology in general. Via p-adic uniformization, we relate the cohomology of the Rapoport-Zink space to the cohomology of the supersingular locus of a Shimura variety with no level at p. In the case $n=3$ or $4$, we give a complete description of the cohomology of the supersingular locus in terms of automorphic representations.
Ionic surfactants are commonly employed to modify the rheological properties of fluids, particularly in terms of surface viscoelasticity. Concurrently, external electric fields can significantly impact the dynamics of liquid threads. A key question is how ionic surfactants affect the dynamic behaviour of threads in the presence of an electric field? To investigate this, a one-dimensional model of a liquid thread coated with surfactants within a radial electric field is established, employing the long-wave approximation. We systematically investigate the effects of dimensionless parameters associated with the surfactants, including surfactant concentration, dilatational Boussinesq number ${\textit{Bo}}_{\kappa \infty }$ and shear Boussinesq number ${\textit{Bo}}_{\mu \infty }$. The results indicate that increasing the surfactant concentration and the two Boussinesq numbers reduces both the maximum growth rate and the dominant wavenumber. In addition, both the electric field and surfactants mitigate the breakup of the liquid thread and the formation of satellite droplets. At low applied electric potentials, the surface viscosity induced by surfactants predominantly governs this suppression. Surface viscosity suppresses the formation of satellite droplets by maintaining the neck point at the centre of the liquid thread within a single disturbance wavelength. When the applied potential is high, the electric stress has two main effects: the external electric field exerts a normal pressure on the liquid thread surface, suppressing satellite droplet formation, while the internal electric field inhibits liquid drainage. Surface viscosity further stabilizes the system by suppressing flow dynamics during this process.
Digital financial inclusion (DFI) has been widely recognized for its potential role in reducing poverty by fostering entrepreneurship. However, whether DFI benefits all social classes equally remains an open question. Integrating technology adoption and income stratification research, this study investigates the impact of DFI on income stratification – specifically lower-, middle-, and upper-income classes – across key entrepreneurial stages, including venture creation, investment, and performance. Using data from 36,557 household-wave observations in the China Household Financial Survey (CHFS), we find that (1) lower-class households are less likely to establish entrepreneurial ventures compared to upper-class households but are more likely to do so than middle-class households, and (2) they make lower investments in entrepreneurial ventures compared to their upper-class counterparts, and experience lower entrepreneurial performance than middle- and upper-class households. The results also show that, whereas DFI positively influences entrepreneurial venture creation, investment, and performance for lower-class households, these effects are less pronounced compared to those observed in middle- and upper-class households. The study advances an integrated view of DFI by examining its differential impacts across income classes and entrepreneurial stages and contributes to the ongoing debate about its effectiveness as a universal poverty reduction solution.
Consultation-liaison psychiatry (CLP) refers to the subspecialty of psychiatry and the specialist clinical services that deliver care at the intersection of mental and physical healthcare. CLP services provide specialist medical and multidisciplinary expertise for managing conditions in these areas of mental and physical healthcare overlap, and comorbidity. The Model of Care for CLP was identified as a key priority in Sharing the Vision, the 2020 national mental health policy in Ireland. Following four years of work by a writing group initiated by the Faculty of Liaison Psychiatry at the College of Psychiatrists of Ireland, the Model of Care for CLP in Ireland was launched in May 2025 (Cpsychi H (2025). Consultation-Liaison Psychiatry: A Model of Care for Ireland. Dublin: HSE.).). Consultation-Liaison Psychiatry: A Model of Care for Ireland. Dublin: HSE.). This reflects the collaborative efforts between the Liaison Faculty and the Irish Health Service Executive (HSE). This Model of Care, developed in collaboration with clinicians and patients, the College of Psychiatrists of Ireland, and the HSE, provides a potential template for future collaborations in the development and implementation of National Mental Health policy.
Sustainable management of watersheds to secure freshwater resources and maintain ecological stability relies on adopting land-use strategies supporting diverse ecosystem services through natural processes. This necessitates systematic evaluation of prospective land-use practices and their associated costs and benefits. We conducted a comprehensive economic evaluation of pro-watershed land-use options, focusing on a well-recognized agroforestry system with alternative organic cultivation in the Navnera watershed in Rajasthan, India. We adopted the ‘total economic valuation’ framework, using the revealed preference approach for monetary evaluation and modelling indirect benefits primarily through Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST). Our findings indicate that the total economic value of ecosystem services in this watershed has the potential to increase by 4.6% with the adoption of agroforestry and only by 1.3% under organic farming compared to current land-use practices. While agroforestry might reduce farmland revenue and water yield, it compensates for these with other important environmental benefits such as water purification, sediment reduction, nutrient retention and carbon sequestration. This local-scale appraisal of ecosystem services helps policymakers understand the cost–benefit dynamics of watershed land-use changes, which is vital for developing effective management strategies through the involvement of local communities.
As a step towards realising a skin-friction drag reduction technique that scales favourably with Reynolds number, the impact of a synthetic jet on a turbulent boundary layer was explored through a study combining wind-tunnel measurements and large eddy simulations. The jet was ejected in the wall-normal direction through a rectangular slot whose spanwise dimension matched that of dominant large-scale structures in the logarithmic region to target structures of that size and smaller simultaneously. Local skin-friction reduction was observed at both $x/\delta =2$ and $x/\delta =5$ downstream of the orifice centreline, where $\delta$ is the boundary-layer thickness. At $x/\delta =2$, the skin-friction reduction was observed to be due to the synthetic-jet velocity deficit intersecting the wall. At $x/\delta =5$, evidence from the simulations and wind-tunnel measurements suggests that a weakening of wall-coherent velocity scales is primarily responsible for the skin-friction reduction. Local skin-friction reduction which scales favourably with Reynolds number may be achievable with the synthetic jet employed in this study. However, there are many technical hurdles to overcome to achieve net skin-friction drag reduction over the entire region of influence. For instance, regions of skin-friction increase were observed close to the orifice ($x/\delta \lt 2$) and downstream of the orifice edge due to the induced motion of synthetic-jet vortical structures. Additionally, a recirculation region was seen to form during expulsion, which has implications for pressure drag on non-planar surfaces.