Accurate and reliable on-site detection of explosives and their precursors remains critical for first responders and EOD teams. While portable spectroscopic techniques such as Raman and FTIR are widely used for this purpose, their limited sensitivity and robustness when analysing heterogeneous real-world specimens such as Homemade Explosives (HMEs) lead to high false-negative rates in the field. This study presents a cloud-based hierarchical machine learning framework integrated with handheld NIR spectroscopy to improve detection robustness. The two-level approach provides high-sensitivity screening at Level 1 (explosive/precursor family detection) and refined subclass characterization at Level 2 (e.g., moisture state, composition). The model was trained on approximately 17,000 NIR scans (similar to 5000 averaged samples from similar to 550 substances). Performance was assessed using bootstrapping and an independent EOD operational dataset (195 explosives, 10 precursors, 65 true negatives). The best ensemble model achieved 96.3% accuracy on the independent EOD data set, with a 3.1% false-negative rate (96.9% true positive rate) and 0% false-positive rate among the chemical families represented in training. This corresponds to a substantial reduction in false negatives compared to previously reported portable NIR and Raman studies. Importantly, the hierarchical structure ensures that missed subclass identification does not compromise initial threat detection, providing an inherent safety margin for field screening. These results demonstrate that combining hierarchical classification with large-scale, variability-driven training significantly enhances the reliability of portable NIR-based detection. The cloud-based framework enables continuous model updates through the integration of field data. Remaining limitations include intrinsic NIR insensitivity for certain inorganic salts and dependence on representative training variability. Future integration with complementary techniques such as Raman spectroscopy offers a pathway toward comprehensive, field-deployable multi-sensor detection systems.
A core aim of educational systems is the nurturing of certain values in students, but underlying mechanisms remain unclear, leaving teachers without guidelines. Our framework considers teachers as attachment and authority figures who influence students' personal values, and physical education (PE) as a context that can foster this social influence. We experimentally tested if PE teacher communication of personal values influences students’ personal values, attitudes and post-experiment self-reported behaviour, and if this social influence is reinforced by the intensity of physical engagement in PE tasks. The results of our 2 (teacher value: healthy eating vs. control) x 2 (intensity of physical engagement: low vs. high) design (n = 207) confirmed our hypotheses. According to our framework, exploratory analyses moreover revealed that intense physical engagement strengthened student perceptions of teacher support, which enhanced student adherence to teacher values. These findings highlight how PE teachers can instil socially useful values in future citizens.
Reduced tillage combined with native/spontaneous cover crops are increasingly promoted as climate-smart practices to enhance soil organic carbon (SOC) storage in dryland agriculture, yet the mechanisms controlling carbon and nitrogen (N) stabilization under semiarid Mediterranean conditions remain insufficiently understood. In particular, the effectiveness of these practices may depend not only on plant biomass inputs, but also on plant residue quality, soil texture, microbial activity, and aggregate-mediated protection. In this long-term study (6-20 years), the effects of reduced tillage (twice a year) combined with native cover crops (RT + NCC), relative to traditional tillage (TT; 3-5 times per year to maintain bare soil), were assessed in the top 15 cm of soil (corresponding to the tillage depth) across three rainfed semiarid almond (Prunus dulcis Mill.) orchards with contrasting soil types (Calcisol and Regosol). Their influence on (i) soil aggregate distribution and stability, (ii) the quantity and quality of OC and N pools across soil aggregate fractions, and (iii) microbial activity and carbonnitrogen dynamics was evaluated. Soil response to management was strongly site-dependent. The clearest effect was observed in the silty loam soil, where reduced tillage combined with native cover crops increased the free macro and occluded aggregates percentage (about 120%), stimulated microbial activity (enzymatic activities, microbial biomass and mineralized OC), and promoted the redistribution of OC and N into more physically protected pools (increased of about 50% in OC and 35% in N concentration within the occluded aggregates). The soils with higher sand content strongly constrained management outcomes. Across sites, plant residue quantity alone did not explain the observed responses, which were also shaped by residue biochemical quality and local edaphic conditions. Importantly, management practices effects were more evident at the aggregate-fraction level than in bulk soil, where total SOC and N often showed limited changes despite clear increases in protected fractions. Overall, our results demonstrate that the stabilization of OC and N in semiarid Mediterranean almond orchards is governed by the interaction among soil texture, plant residue quality, microbial activity, and physical protection within aggregates. These findings highlight the need for site-specific strategies that maximize the transfer of fresh organic inputs into persistent and protected soil OC fractions.
How does a person’s immigration status shape well-being, integration and opportunities? Immigration status is particularly high-stakes for people fleeing persecution and violence, who may face uncertainty in their ability to reside legally and move freely. Yet there is limited causal evidence on how obtaining refugee status affects refugees’ lives after arrival. In this study, we address this empirical gap by combining administrative UNHCR records linked to an original panel survey of asylum seekers and refugees in Greece conducted between 2022 and 2023. We use a difference-in-differences design to identify the impact of refugee status on labor market outcomes, integration into host communities, psychological distress and onward migration. We find that obtaining refugee status from the Greek state reduces psychological distress and improves overall integration, with the effects being mostly driven by navigational integration, while also increasing secondary movements within Europe. These results are robust to a variety of checks and specifications, providing evidence for the multidimensional impact of granting refugee status.
Introduction: This study aimed to assess the psychometric validity of the 12-item Burnout Assessment Tool (BAT-12) among bus drivers - a high-risk but understudied occupational group across the three main linguistic regions of Switzerland (German, French, and Italian). Methods: The study sample comprised 494 bus drivers who completed the BAT-12 in the Transport Personnel Health Cohort (TRAPHEAC) study. Content validity was assessed by expert ratings and user interviews in French. Structural validity was examined using CFA, and cross-cultural validity through differential item functioning (DIF) analyses. Construct validity was evaluated through convergent, divergent, and discriminative analyses based on pre-defined hypotheses. Results: Both the correlated four-factor and second-order four-factor CFA models showed satisfactory fit, supporting the multidimensional structure of the BAT-12. For the French version, 9 of the 12 items met the prespecified item-level content validity threshold, while the scale-level SCVI/Ave was 0.861, approaching but not attaining the 0.90 value recommended for excellent content validity. Ordinal logistic regression identified uniform DIF for items 2 and 7 in the German-French comparison and for items 2 and 12 in the German-Italian comparison; nonuniform DIF was detected for item 8 in the German-Italian comparison. Sensitivity analyses indicated that excluding DIF-flagged items had little impact on the overall between-language comparisons. Most construct-validity hypotheses were supported, although the association between the BAT-12 and the BDI-II was stronger than expected. Discriminative validity analyses showed higher BAT-12 scores among groups expected to be at greater risk of burnout. Conclusion: In Swiss bus drivers, the BAT-12 showed good structural and construct validity. Crosslanguage content comparability requires further investigation.
