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This paper explores the intersection of Nigerian criminology and the United Nations Sustainable Development Goals (SDGs), highlighting the opportunities and future directions for aligning criminological research, education and practice with global development priorities. While Nigeria faces complex challenges such as poverty, inequality, insecurity, gender-based violence, environmental degradation and ineffective justice institutions, criminologists have a vital role in finding sustainable solutions. This paper explores how specific SDGs, notably Goals 3, 4, 5, 8, 9, 11, 13 and 16, provide significant opportunities for criminological involvement, including crime prevention, youth empowerment, community safety and tackling cybercrime. It suggests that incorporating SDGs into criminology curricula, enhancing data collection, encouraging field research, shaping policy reforms and accessing global funding can greatly improve the impact and relevance of the discipline. By taking an interdisciplinary, culturally aware and community-focused approach, Nigerian criminologists can advocate for evidence-based reforms that confront both the immediate and underlying factors of crime and insecurity. The paper concludes that aligning Nigerian criminology with the SDGs offers a timely chance to bolster academic and policy relevance while also serving as a strategic avenue for promoting peace, justice and inclusive development in Nigeria.
The wake merging of two side-by-side porous discs with varying disc spacing is investigated experimentally in a wind tunnel. Two disc designs used in the literature are employed: a non-uniform disc and a mesh disc. Hot-wire anemometry is utilised to acquire two spanwise profiles at 8 and 30 disc diameters downstream and along the centreline between the dual-disc configuration up to 40 diameters downstream. The spanwise Castaing parameter profiles confirm the appearance of rings of internal intermittency at the outermost parts of the wakes. These rings are the first feature to interact between the discs. After this point, the turbulence develops to a state whereby an inertial range is observable in the spectra. Farther downstream, the internal intermittency shows the classical features of homogeneous, isotropic turbulence. These events are repeatable and occur in the same order for both types of porous discs. This robustness allows us to develop a general map of the merging of the two wakes.
This paper presents an experimental and analytical investigation into the use of trailing edge slits for the reduction of aerofoil trailing edge noise. The noise reduction mechanism is shown to be fundamentally different from conventional trailing edge serrations, relying on destructive interference from highly compact and coherent sources generated at either ends of the slit. This novel approach is the first to exploit the coherence intrinsic to the boundary layer turbulence. Furthermore, the study demonstrates that trailing edge slits not only achieve superior noise reductions compared with sawtooth serrations of the same amplitude at certain conditions, but also offer frequency-tuning capability for noise reduction. Noise reduction is driven by the destructive interference between acoustic sources at the root and tip of the slit, which radiate with a phase difference determined by the difference in times taken for the boundary layer flow to convect between the root and tip. Maximum noise reductions occur at frequencies where the phase difference between these sources is $180^\circ$. The paper also presents a detailed parametric study into the variation in noise reductions due to the slit length, slit wavelength and slit root width. Additionally, a simple two-source analytic model is proposed to explain the observed results. Wind tunnel measurements of the unsteady flow field around the trailing edge slits are also presented, providing insights into the underlying flow physics.
The linear stability of a thermally stratified fluid layer between horizontal walls, where non-Brownian thermal particles are injected continuously at one boundary and extracted at the other – a system known as particulate Rayleigh–Bénard (pRB) – is studied. For a fixed volumetric particle flux and minimal thermal coupling, reducing the injection velocity stabilises the system when heavy particles are introduced from above, but destabilises it when light particles are injected from below. For very light particles (bubbles), low injection velocities can shift the onset of convection to negative Rayleigh numbers, i.e. heating from above. Particles accumulate non-uniformly near the extraction wall and in regions of strong vertical flow, aligning with either wall-impinging or wall-detaching zones depending on whether injection is at sub- or super-terminal velocity. The increase of the volumetric particle flux always enhances these effects.
We construct an fpqc gerbe $\mathcal {E}_{\dot {V}}$ over a global function field F such that for a connected reductive group G over F with finite central subgroup Z, the set of $G_{\mathcal {E}_{\dot {V}}}$-torsors contains a subset $H^{1}(\mathcal {E}_{\dot {V}}, Z \to G)$ which allows one to define a global notion of (Z-)rigid inner forms. There is a localization map $H^{1}(\mathcal {E}_{\dot {V}}, Z \to G) \to H^{1}(\mathcal {E}_{v}, Z \to G)$, where the latter parametrizes local rigid inner forms (cf. [8, 6]) which allows us to organize local rigid inner forms across all places v into coherent families. Doing so enables a construction of (conjectural) global L-packets and a conjectural formula for the multiplicity of an automorphic representation $\pi $ in the discrete spectrum of G in terms of these L-packets. We also show that, for a connected reductive group G over a global function field F, the adelic transfer factor $\Delta _{\mathbb {A}}$ for the ring of adeles $\mathbb {A}$ of F serving an endoscopic datum for G decomposes as the product of the normalized local transfer factors from [6].
The modal auxiliary form must plus perfect aspect (must have +V-en) has recently acquired the meaning of direct evidentiality in Multicultural London English, the new London dialect. Because the new meaning is a recent innovation we have a rare opportunity to witness its development at first hand, unlike earlier changes in the history of must. Our analysis supports the view that the classic definition of evidentiality in terms of information source is too narrow to explain the expression of evidentiality in spoken interaction, and that a broader definition in terms of epistemic authority is more appropriate. We argue that the direct evidential meaning is a coherent further step in the semantic changes undergone by must during its history. It represents a previously undocumented pathway in the grammaticalisation of evidentiality. It also supports the view that evidentiality is not a purely lexical phenomenon in English.
We simulate thermal convection in a two-dimensional square box using the no-slip condition on all boundaries, and isothermal bottom and top walls, and adiabatic sidewalls. We choose 0.1 and 1 for the Prandtl number $Pr$ and vary the Rayleigh number $Ra$ between $10^6$ and $10^{12}$. We particularly study the temporal evolution of integral transport quantities towards their steady states. Perhaps not surprisingly, the velocity field evolves more slowly than the thermal field, and its steady state – which is nominal in the sense that large-amplitude low-frequency oscillations persist around plausible averages – is reached exponentially. We study these oscillation characteristics. The transient time for the velocity field to achieve its nominal steady state increases almost linearly with the Reynolds number. For large $Ra$, the Reynolds number itself scales almost as $Ra^{2/3}\, Pr^{-1}$, and the Nusselt number as $Ra^{2/7}$.
This paper presents the design, control strategy, and preliminary testing of Epi.Q, a modular unmanned vehicle (UGV) tailored for challenging environments, including exploration and surveillance tasks. To manage the complexities of the articulated structure, including lateral slip and the risk of jackknifing, a fuzzy logic-based traction control system was implemented. To improve traction stability by modulating power distribution between modules, the system optimally controls steering and traction. Subsequently, the paper introduces the fuzzy control system and presents preliminary validation experiments, including hill-climbing, obstacle navigation, steering, and realignment tests. Preliminary results indicate that the proposed fuzzy control strategy significantly improves traction and maneuverability even on steep inclines and uneven surfaces. These findings highlight the potential for fuzzy logic control to improve UGV performance.
The study aim is to validate the utility and implications of the Manjila jugular bulb classification.
Methods
A retrospective study of 182 patients who underwent lateral skull base or otologic surgery was conducted. Pre-operative temporal bone computed tomography and magnetic resonance imagery scans were reviewed, and the classification was independently applied by a neuroradiologist and neuro-otologist. Concordance among imaging, intra-operative findings, complications, and functional outcomes was assessed.
Results
Substantial agreement was found between imaging and intra-operative findings (Cohen’s kappa = 0.78). High-riding jugular bulbs were present in 13.7 per cent of cases, with complications such as venous bleeding (5.5 per cent) and cranial nerve palsy (2.7 per cent). Surgical approaches were altered in 25 per cent of cases. Functional outcomes, including hearing and facial nerve preservation, were not correlated with jugular bulb grades.
Conclusion
The classification demonstrated strong concordance with intra-operative findings, emphasising the importance of pre-operative identification for tailored surgical planning.
The evolution of the crystal structure and mechanical behavior of Ca-montmorillonite (Ca-Mnt) under varying degrees of hydration is crucial for understanding its swelling properties. The objective of the present study was to investigate systematically the microstructural changes and stress–strain response of Ca-Mnt through molecular dynamics (MD) simulations, supplemented by experimental validation. By employing stress–strain hysteresis curves, the equivalent damping ratio was characterized by quantifying the impact of hydration on energy dissipation. The results indicated that, within the investigated hydration range, the absolute value of the mean H2O–Mnt interfacial interaction energy decreased with increasing hydration; as the water content increased from 300 mgwater per gclay to 420 mgwater per gclay, the average interfacial energy was reduced by ~2.65 eV Å–2. Hydration had a significant influence on the mechanical properties of Ca-Mnt, particularly in the Z-direction, in which the tensile strength decreased, whereas the compressive strength increased with greater degrees of hydration. The stress–strain hysteresis curves shifted progressively to the right as hydration intensified, demonstrating pronounced non-linearity and energy dissipation characteristics. The equivalent damping ratio initially decreased and then increased with increasing degrees of hydration, highlighting the dual effect of hydration on energy dissipation. This study validates the reliability of the simulation results and provides theoretical insights for understanding the hydration-induced expansion mechanisms of montmorillonite and its engineering applications.
An analytical formulation is provided that describes the first two natural modes of the fluid–structure interaction of an incompressible current with a pitching and heaving flexible plate. The objective is twofold: first, to present a general derivation of analytical expressions for the lift, moment and the flexural moments exerted by an inviscid flow on a pitching and heaving plate whose deformation is general enough that the coupling of the flexural moments with the structural equations allows solving analytically the first two natural modes of the system; second, to analyse the propulsion performance of the foil when actuated near the first two natural frequencies. For the second purpose, one also needs the thrust force generated through the motion and the general deformation of the foil considered, which is analytically derived using the linearized vortex impulse theory, extending and systematizing previous works. The analytical expressions, once viscous effects are taken into consideration through nonlinear transverse damping and offset drag coefficients, are compared with small-amplitude available experimental data, discussing their limitations. It is found that low stiffness pitching and heaving are quite different, with a pitching flexible foil only generating thrust near the second resonant frequency, whereas heaving always generates thrust, with the maximum slightly below the second natural frequency. Maximum thrust for large stiffness pitching is around the first natural frequency. The maximum efficiency occurs at frequencies close to the first natural mode if the foil is sufficiently rigid, but it is not related to the natural frequencies as the rigidity decreases.
As more governments commit to feminist foreign policies (FFPs), this commitment trickles down to a central foreign policy area: peacebuilding. As a field, peacebuilding has historically been dominated by western states and western-dominated institutions performing interventions along the hegemonic liberal peacebuilding paradigm (Lederach 1997; Mac Ginty 2008). This has, in turn, provoked significant feminist criticisms and interventions (Duncanson 2016; Hewitt and True 2021; McLeod 2018). When Germany, the largest peacebuilding funder globally (Rotmann, Li, and Stoffel 2021; UN Peacebuilding 2024), announced their FFP in 2023, this development opened up the prospect for substantial feminist change, but also raised questions about what such change might look like in practice.
Are shifting party-union relationships impacting the vote intentions of union members in Canada? By analyzing voting intentions within the Canadian labour movement, the findings illuminate the complexity of union members’ electoral behaviour and the strategic opportunities for parties vying for their votes. The authors find that while union members continue to be more likely than the average voter to support the NDP, this support is nuanced by factors such as union type, gender, education, age, and income. Notably, the study finds that the Conservatives have made significant inroads among construction union members and those with college education, challenging traditional assumptions about Canadian labour politics.
This article is concerned with the history of eugenic sterilisation in Britain through the 1920s and 1930s. In this period, the Eugenics Society mounted an active but ultimately unsuccessful campaign to legalise the voluntary surgical sterilisation of various categories of people, including those deemed ‘mentally deficient’ or ‘defective’. We take as our explicit focus the propaganda produced and disseminated by the Eugenics Society as part of this campaign, and especially the various kinds of data mobilised therein. The parliamentary defeat of the Society’s Sterilisation Bill in July 1931 marks, we argue, a significant shift in the tactics of the campaign. Before this, the Eugenics Society framed sterilisation as a promising method for eradicating, or at least significantly reducing the incidence of, inherited ‘mental defect’. Subsequently, they came to emphasise the inequality of access to sterilisation between rich and poor, (re)positioning theirs as an egalitarian campaign aimed at extending a form of reproductive agency to the disadvantaged. These distinct phases of the campaign were each supported by different kinds of propaganda material, which in turn centred on very different types of data. As the campaign evolved, the numbers and quantitative rhetoric which typified earlier propaganda materials gave way to a more qualitative approach, which notably included the selective incorporation of the voices of people living with hereditary ‘defects’. In addition to exposing a rupture in the Eugenics Society’s propagandistic data practices, this episode underscores the need to further incorporate disabled dialogues and perspectives into our histories of eugenics.