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Partnering with our environment to manage our wastes: land application of drinking water treatment and wastewater treatment sludges in sandy soils
Full text linkThe application of sewage sludge to agriculture is particularly risky in sandy soils, due to pollutant mobility. However, these nutrients are most needed in these soils, which are widely distributed in Southern Africa. This perspective piece investigates the co-amendment of water treatment residuals (WTR) to promote soil integrity, analogous to the sorptive properties of clay, fortifying nutrient-poor sandy soils to receive sewage sludge. Ecological motivations like biomimicry, environmental carrying capacity and evolutionary adaptation were explored. Land application was compared to other sludge re-use options, focusing on practical considerations. The local distribution of sandy soils and their agricultural consequences were mapped, with an exploration of the high-value crops ideal for this strategy – harnessing crop growth for pollutant remediation and minimizing downstream market risks. The economic benefits and challenges were explored in the ‘sandbox’ of the Philippi Horticultural Area, where a co-diversion strategy was modelled using simple cost analyses. Public participation was explored through the vehicle of eco-conscious markets and certification. Finally, a relatively consistent WTR and sewage sludge production ratio was shown across provincial, national and international urban development, a golden thread facilitating this waste management strategy
TREASURE: a cusTomisable seRious gamE frAmework for School cUltuRe lEarning
No full textThis study addresses the challenges faced by foreign guardians in navigating unfamiliar educational practices by proposing a serious game framework called TREASURE (a cusTomisable seRious gamE frAmework for School cUltuRe lEarning). This framework outlines key design principles for serious games aimed at multicultural education, including multilingual support, a customizable user dashboard, gender-specific pronunciations, at least one multimedia-based exploration mode for accessing structured school event information, and a quiz mode with immediate feedback to enhance learning through interaction and visual reinforcement. Moreover, to illustrate the key components and design structure of TREASURE, a prototype game was elaborately implemented
Structural and Dynamic Origins of Payne Effect Reduction by Steric Stabilization in Silica Reinforced Poly(butadiene) Nanocomposites
Full text linkSilica nanoparticles in polybutadiene nanocomposites cause significantly hindered polymer dynamics in the form of a glassy layer, which can extend more than 10 nm from the nanoparticle surface. We present experiments for a well‐defined series of these nanocomposites to contrast the contributions of free chain ends versus hindered dynamics on the non‐linear rheological effects associated with energy loss in transport. Quasi‐elastic neutron scattering (QENS) experiments using isotopic labeling and interfacially‐active polymers enabled quantification of the glassy layer's thickness, which we relate to the strain softening (Payne effect), energy dissipation and the previously established nanostructure of the materials. We explored the thickness of the glassy layer from near the bulk glass transition temperature up to 363 K, in the presence or absence of nanoparticles and interfacially active polymers. Although the glassy layer becomes thinner with increasing temperature, it remains significant (> 3 nm) even when the sample is more than 180 K above the bulk glass transition temperature. This layer can account for the substantial levels of reinforcement, up to a factor of 20, and energy dissipation observed in silica filled rubbers beyond values expected from particle volume fraction arguments alone. Since the interfacially‐active polymers simultaneously inhibit nanoparticle aggregation and introduce polymer chain ends to the interparticle region, these experiments provide a direct test of whether energy loss in reinforced nanocomposites is attributable to “glassy bridges” between particles or chain ends. We show that while chain ends may be significant at low strain, below 1%, the percolation of the glassy layer of hindered polymer dynamics between silica particles dominates the Payne effect at high strain (~10% or more) and that this contribution can be dramatically reduced by sufficient steric stabilization to the nanoparticles
From market access to regulatory cooperation in the Greater Bay Area (GBA): an international economic law perspective
Full text linkOne unique challenge that the Greater Bay Area (GBA) development presents to policymakers is how heterogeneous regulatory frameworks in three different legal jurisdictions within a single sovereign state can be coordinated to facilitate cross-border transactions while respecting the region’s diverse legal traditions. This article argues that, as trade liberalization in goods and services has largely been achieved in the GBA, market access is no longer the primary challenge to its development. Moving forward, regulatory cooperation is a critical factor for the success of the GBA. Deep regulatory cooperation will significantly enhance the business environment, attract domestic and international investors, and strengthen the GBA’s global competitiveness. Moreover, the GBA can draw inspiration from best practices in high-standard regional trade agreements to advance regulatory cooperation
Uneven development and the geographies of energy transition in Mozambique
Full text linkIn Mozambique, sustainable energy access is an increasing priority for a diverse range of actors seeking to improve livelihoods and stimulate economic development—particularly in rural areas where energy infrastructure remains limited. Drawing on field research conducted as part of a comparative three-year project examining the potential of community energy systems to foster inclusive, just, and clean energy transitions in Southern and East Africa, this paper develops a critical, policy-relevant and geographically grounded analysis of Mozambique's energy transitions, which are unfolding across multiple fronts. Our analysis addresses both the move away from conventional or ‘traditional’ energy sources to ‘modern’ energy services, and the shift toward renewable energy technologies. We argue that while Mozambique has taken important steps toward a cleaner energy future there remain significant constraints to progress and that it is crucial to consider the advancement of renewable energy in relation to the country's embedded resource and extractive geographies that shape the directions, possibilities, and spatial dynamics of transition. We examine the broader policy environment, focusing on the state's energy transition strategy and its implications for energy justice, spatial inequality, and economic opportunity. Particular attention is given to the role and potential of decentralized, off-grid energy systems, emphasizing the need for greater community participation in both policy design and implementation. Finally, we develop a political economy framework to analyse the influence of state institutions, international donors, and private capital in shaping Mozambique's energy transitions, and assess their impacts on energy poverty and the goal of equitable, sustainable energy access
A theoretical appraisal of the GR4J rainfall-runoff modelling framework
Full text linkThe GR4J (Génie Rural à 4 paramètres Journalier) model is a widely used conceptual rainfall-runoff model that simulates river flow from daily precipitation and potential evapotranspiration data. This article presents a theoretical appraisal of GR4J with two primary objectives: (1) to establish clearer links between its heuristic components and physically-based hydrological processes, and (2) to identify practical modifications to minimise the need for operator splitting within its analytical solution framework. We show that GR4J’s soil water model is mathematically identical to the Probability Distributed Model (PDM), although it employs a fixed probability density function that resembles a log-normal distribution, while its empirical unit hydrograph can be moment-matched with a diffusion wave model derived from the Saint-Venant equations. Furthermore, while percolation can be conceptually appropriate for some catchments, we demonstrate that operator splitting can be entirely avoided by omitting percolation, assuming inter-catchment groundwater exchange is a linear function of discharge rate and adopting an alternative exponential storage function analytical solution for the non-linear flow routing store. We propose a revised model structure that is more physically interpretable and computationally efficient than the original GR4J formulation. Testing our modifications across 671 catchments in the UK revealed minimal impacts on model calibration and validation performance. This work provides a deeper theoretical basis for key empirical aspects of GR4J and introduces an operator-splitting-free formulation expected to yield more numerically reliable results
Geographical and environmental dependencies in multivariate count models: Recreation demand for Italian National Parks
Full text linkWe propose an innovative spatial-based multivariate Generalized Poisson regression model to explain the number of outdoor recreation trips to protected areas. The innovation consists of capturing the impact of geographical and environmental similarities across destinations. As a proof of concept, the approach is applied to data obtained from an online survey with 794 respondents sampled from across Italy between October and November 2022. The attention is placed on assessing travellers’ preferences for four popular Italian National Parks: the Parco Nazionale delle Dolomiti Bellunesi, the Parco Nazionale dell’Appennino Tosco Emiliano, the Parco Nazionale delle Cinque Terre, and the Parco Nazionale dell’Abruzzo, Lazio e Molise. The results corroborate the existence of strong spatial and environmental correlation patterns across the nature sites under assessment. Further, the multivariate approach enhances the predictive accuracy of trip count frequencies relative to simpler models used for comparison
Tall talks about elephants: Hannibal’s crossing through disciplines
Full text linkThe enigma of Hannibal’s Alpine crossing has captivated minds and sparked debates across centuries, much like an elusive puzzle that resists a definitive solution. This article explores the fierce and often acrimonious scholarly debates surrounding Hannibal’s journey, where the quest to separate historical fact from romantic myth has turned into a battleground for competing disciplines. Military historians, geographers and philologists have all staked their claims, each employing distinct methods to argue their case, yet the controversy has only intensified. As the debate has evolved, the focus has shifted from merely identifying the route to examining how historical truths are constructed amid academic rivalries. The article scrutinizes the rhetorical strategies and epistemological conflicts that have defined this ongoing dispute, revealing how the quest to solve Hannibal’s mystery has often led to sharp intellectual skirmishes. These clashes, far from resolving the issue, have instead highlighted the complexities of reconstructing ancient events with limited and sometimes contradictory information. Ultimately, these debates, as harsh as they may be, have contributed to elevating the Western Alps as a zone of historical attention and prestige, now increasingly exploited for heritage
Impact of suction and swell-induced softening on pile behavior in an unsaturated expansive clay
Full text linkThis study examined the response of a single pile embedded in an unsaturated expansive clay. This was achieved by performing three-dimensional finite-element analyses, employing the Barcelona Basic Model. The study aimed to quantify the contribution of suction and swell-induced softening in dictating the mobilization of shaft resistance. Centrifuge testing was used as a benchmarking study to simulate free-swell and pile pullout response. The resulting coupled hydromechanical flow deformation analyses effectively captured swell evolution, changes in lateral swell pressure, and swell-induced softening, all of which significantly influenced load mobilization along the pile length. The results obtained identified zones of both positive and negative shaft resistance along the pile, previously overlooked by studies focusing solely on the development of positive resistance within the active zone. The development of tensile load in the pile was closely correlated with the reduction in suction and resulting swell upon wetting. During initial wetting, reduction of suction to the air occlusion value (where only 18% of total swell had been achieved) produced the maximum tensile load, after which reductions in load were observed. Furthermore, in comparison to rainfall infiltration, a rise in the water table was found to be a more critical hydraulic condition, generating maximum axial load and pile uplift. The study also highlighted conservatism in calculating pile capacity based on saturated soil mechanics, with the capacity found to be around five times lower than under unsaturated conditions. These findings enhance the understanding of pile foundation design in unsaturated expansive clays
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