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Sources, pathways, and health risk assessment of harmful elements in soil and crops: a case study from East Cameroon
No full textThis study aimed to assess the contamination of soils by potentially harmful elements (PHEs), their transfer to food crops, and the potential health risks to humans. Samples of four rock types, ten soil samples, and six staple food crop samples were collected from representative sites and analyzed for cations using inductively coupled plasma mass spectrometry and for anions using ion chromatography. The mean concentrations (mg/kg) of Fe, Al, Cr, Mn, Ba, Zn, Pb, NO3−, Ni, Cu, Co, As, Se, and F− exceeded the safe limits set by the Food and Agriculture Organization. The pollution load index was > 3 for Mn, Cr, Pb, Se, and NO3−. The geoaccumulation index was > 1 for all elements except Se. The ecological risk index was > 300 solely for Mn. Statistical analysis and GIS-based geospatial plots indicated pollution from both geogenic and anthropogenic sources. Non-carcinogenic risk (HQ) was > 1 for NO3− and Fe in adults and > 1 for Mn, Fe, Al and Cr in children. The bioaccumulation factors were higher in vegetables than in grains. The cumulative hazard index (HI) was low for Cr, Co, and Se in adults, while in children, it was low for Ni, Se, and Ba. Carcinogenic risk indices indicated that Cr posed the highest risk among all PHEs, with children being more vulnerable than adults. Overall, children had a higher exposure to PHEs compared to adults. The findings highlight the human health risks associated with PHE exposure from contaminated agricultural systems, particularly in semi-arid regions.</p
“Closeted” cause lawyering in authoritarian Cambodia
No full textUsing Cambodia as a case study, this article examines cause lawyering in a repressive political environment. It focuses on “closeted” cause lawyering, a practice that we define as the intentional pursuit of change through the legal process that is concealed for strategic purposes. Situated within the wider scholarship on (cause) lawyering in general and authoritarian Southeast Asia and China in particular, the article draws upon interviews conducted over seven years in Cambodia with 37 lawyers and human rights defenders working in practice areas considered politically controversial by the authoritarian state. We identify how closeted cause lawyers operate in such a way as to ensure professional and personal survival while quietly advancing their goals across three settings, including dignity restoration work with clients, legal professionalism in court and sustaining a moral community of like-minded lawyers. The article underscores the ongoing relevance of cause lawyering even where intentionality must be hidden, as well as the enduring importance of cause lawyers’ efforts to preserve an ideal of the rule of law. We conclude by suggesting that the authoritarian turn in a range of democracies, including the Unites States, suggests that closeted cause lawyering may be required to defend democracy even among conventional lawyers
C3HeB/FeJ mice with chronic Mycobacterium avium complex pulmonary infection exhibit impaired respiratory function but not necrotising granulomatous disease
No full textBackgroundMycobacterium avium complex (MAC) is driving a global rise in pulmonary disease (MAC-PD) characterised by chronic infection, granulomatous inflammation and impaired respiratory function. Better animal models are needed to screen candidate therapies targeting bacteria and immune-mediated tissue injury. The C3HeB/FeJ mouse was previously reported to model necrotic granulomatous lung infection in MAC-PD following infection with a low-dose inoculum of the clinical isolate MAC2285R. We investigated whether this model was reproducible with variations in MAC strain and inoculating dose.MethodsSix-week-old female C3HeB/FeJ mice were infected intratracheally with a clinical isolate of MAC (MAC2285R) or reference strains (MAC104 or MAC101). Mice were culled at 4-weekly intervals post-infection until week 12. Lungs, spleen and liver were harvested for bacterial burden enumeration and histological examination. Whole body plethysmography (WBP) was performed weekly to measure changes in respiratory function (Buxco system).ResultsC3HeB/FeJ mice infected with low dose inoculum of MAC2285R infection exhibited increasing bacterial lung infection for 8 weeks (p < 0.05), followed by stable lung burden from weeks 8–12. High dose inoculum resulted in stable lung bacterial burden over 12 weeks. Histological analysis revealed only mild inflammatory changes in both low and high dose inoculum groups at weeks 4, 8 and 12 post-infection, with no evidence of necrotising or non-necrotising granulomatous inflammation. Surrogate measures of respiratory effort (frequency, tidal volume, inspiratory and expiratory flow rates) were increased in mice with high dose inoculum compared to uninfected controls (p < 0.001), but not low dose inoculum. Similar findings on lung bacterial burden and histological analysis were found in mice infected with low- and high-dose inoculum of MAC104 and MAC101. MAC104 infection caused greater changes in respiratory function, whereas MAC101 did not significantly affect breathing patterns.ConclusionThe C3HeB/FeJ mouse is susceptible to chronic MAC infection from intratracheal infection with reference and clinical isolates, but this was not associated with severe granulomatous inflammation as previously reported. A low dose inoculum generated a proliferative lung infection, whereas high dose inoculum resulted in chronic, stable lung bacterial burden. Mice with high-dose inoculum MAC2285R and MAC104 infection also displayed evidence of increased respiratory effort.<br/
Cohort profile update: The Northern Ireland Longitudinal Study (NILS)
No full textKey Features• The Northern Ireland Longitudinal Study (NILS)—a linked, administrative dataset comprising ∼28% of the resident population in Northern Ireland was established in 2006 to fulfill a range of academic and policy-research purposes.• A further four census linkages have enabled a lifespan of >40 years for new research on health transitions, migration, social mobility, and other population trends.• The most recent census linkage in 2021 comprised a total cohort of 515 930 people in the age range of 0 to 100+ years.• The new linkage of environmental and school datasets in addition to the latest census provides the opportunity for new topics of research including self-reported chronic health conditions, national identity and language, sexual orientation, and renewable energy.• The NILS has already been used by many researchers in academic and non-academic organizations. For new projects and enquiries, please contact [email protected].<br/
Improving parallel scalability for molecular dynamics simulations in the exascale era
No full textMolecular Dynamics (MD) simulations are time-consuming as they simulate particle-to-particle interactions for increasingly larger particle counts. Applications split these interactions into short-range and long-range interactions at large counts as long-range ones can be approximated with a fundamentally different computation. State-of-the-art implementations map these computations on different processes, often on different nodes, which results in heterogeneous processes with disparate parallel scaling properties, with periodic information exchanges between them. This split and the communication that it requires creates a richer performance optimization space. Our fundamentally novel approach increases asynchrony between the process classes, which implies that up-to-date grid potentials are not always available and so we instead model evolving potentials based on their histories. We provide a theoretical analysis of the accuracy of our approach as well as experimental evaluation of these approximations. We implement our approach in the open-source LAMMPS MD code and detail its implementation in the split Verlet and PPPM algorithms, including the asynchronous communication pattern. The assessment for the preservation of accuracy after incorporating asynchrony needs to consider the following: 1) order of particle-wise inaccuracy introduced relative to the order of inaccuracy of the baseline synchronous numerical integration methods; 2) degree to which statistical trajectories (e.g., heat, pressure, total energy) associated with the simulated system deviate from those of baseline synchronized simulations; 3) degree to which invariants such as total energy in Hamiltonian systems are preserved in using the asynchronous approach. We show a brief analysis in terms of the first consideration, while demonstrating experimental preservation of accuracy of the trajectories and invariants for most of the applications considered. For the heterogeneous process allocations where synchrony is a substantial bottleneck, an asynchronous run can show about 80% speedup over the synchronous run, attributed mostly to the substantial reduction in the time waiting for the grid potential communications
A preliminary psychometric investigation of a brief positive school experiences scale
No full textIntroductionUniversal screening using measures of mental health symptoms is discounted by UK schools due to stakeholder concerns. This is a preliminary study of the psychometric properties of a new Brief Positive School Experiences (B-PSEs) scale, devised to assess associations between cumulative positive school experiences (PSEs) and adolescent mental health as part of a PhD project that explored PSEs count as a potential proxy measure of adolescent mental health risk.MethodsFive teachers developed a brief 19-item PSEs measure. 460 adolescents (aged 14–16) completed a survey based on these items and items measuring mental health (N = 460). Exploratory factor analysis and measures of internal consistency assessed the scale’s preliminary psychometric properties.ResultsThe B-PSEs scale demonstrated a three-factor structure; (1) Coping with school demands; (2) School belonging, safety and support; and (3) Equity and low social adversity. Composite reliability was measured at 0.91.ConclusionThe B-PSEs scale is a reliable measure with a robust factor structure and PSEs scores measured using the scale have demonstrated associations with adolescent mental health outcomes.<br/
Big sister, dog, and ethnic names: semiotic ideologies of self-naming on Xiaohongshu (RED)
No full textThis paper examines the self-naming practices of international students on the Chinese social media platform Xiaohongshu (‘Little Red Book’), focusing on how these practices are shaped by specific semiotic ideologies. Self-naming serves a critical role in understanding the identity processes of international students as they navigate the complexities of cultural differences, social differentiation, and performative demonstrations of ‘doctorateness’ with a domestic audience during their sojourn abroad. Data draw from a cross-disciplinary sample of twenty Chinese doctoral students in the UK, collected through the following qualitative procedures: i) in-depth narrative interviews exploring biographies and histories of engagement with the platform; ii) analysis of posts and messages; and iii) follow-up ‘dialogic-action’ interviews in which participants actively engaged with the platform during discussions. The multiform data was analysed using Mediated Discourse Analysis, focusing on how language, symbols, and self-naming practices are mediated through cross- and intra-cultural contexts, and broader semiotic ideologies of self-naming. The paper discusses three representative examples which collectively underscore themes of showcasing or concealing aspects of identity: ‘big sister’ (姐姐), ‘dog’ (狗), and forms of ‘ethnic names’. Each practice reflects a distinct semiotic ideology, revealing how personal branding intersects with platform affordances and construction of personae to establish individual self-brands as doctoral students abroad. The research highlights the nuanced ways in which international students curate their identities on digital platforms like Xiaohongshu and the importance of critical analyses of language at various substrata of practice.<br/
Convolutional networks can model the functional modulation of the MEG responses associated with feed-forward processes during visual word recognition
No full textTraditional models of reading lack a realistic simulation of the early visual processing stages, taking input in the form of letter banks and predefined line segments, making them unsuitable for modeling early brain responses. We used variations of the VGG-11 convolutional neural network (CNN) to create models of visual word recognition that starts from the pixel-level and performs the macro-scale computations needed for the detection and segmentation of letter shapes to word-form identification of large vocabulary of 10k Finnish words, regardless of letter size, shape, or rotation. The models were evaluated based on an existing magnetoencephalography (MEG) study where participants viewed regular words, pseudowords, noise-embedded words, symbol strings, and consonant strings. The original images used in the study were presented to the models and the activity in the layers was compared to MEG evoked response amplitudes. Through a few alterations to make the network more biologically plausible, we found an CNN architecture that can correctly simulate the behavior of three prominent responses, namely the type I (early visual response), type II (the 'letter string' response), and the N400m. In conclusion, starting a model of reading with convolution-and-pooling steps enables the flexibility and realism crucial for a direct model-to-brain comparison
State-of-the-art virtualisation technologies for the centralised automotive E/E architecture
No full textThe automotive industry is undergoing profound changes, driven by the need for safer, more environmentally friendly, and more accessible future mobility and transport systems for goods and people. Enabling technologies include electrification, digitalisation, and automation of future vehicles. These technologies are powered by a multitude of onboard Electronic Control Units (ECUs). A typical modern vehicle has about 100 physical ECUs to enable various aspects of its function. These legacy many-ECU electronic/electrical (E/E) architecture models, known as distributed E/E architecture, are deemed inefficient as the number of ECUs and their processing power requirements keep increasing. In contrast, emerging centralised E/E architectures propose using fewer physical high-performance onboard processors on which an almost unlimited number of virtual ECUs can be created to handle various legacy and modern applications. As a result, virtualisation techniques, which enable multiple virtual ECUs with different operating systems to run concurrently on a single hardware platform, are promising models for modern centralised E/E architectures. Motivated by this trend, this paper provides a structured and comprehensive state-of-the-art review of virtualisation techniques for automotive applications, covering areas such as resource allocation, AUTOSAR, peripheral I/O interfaces, and in-vehicle communication networks. We comprehensively review the literature and identify research gaps in virtualisation techniques for cache management, paravirtualsation, software-defined networking for in-vehicle networks, and virtualisation for enhanced prototyping and testing in the context of modern E/E architectures for modern vehicles