Universidad de Burgos

Adolescent tobacco use remains a major public health concern (World Health Organization, 2024). In recent years, electronic cigarettes have become a frequent pathway to nicotine initiation, posing new challenges for traditional school-based tobacco prevention strategies.

A repeated cross-sectional observational study was conducted with 5,658 students aged 11 to 18 years from secondary schools in Burgos (Spain), corresponding to six academic cohorts between 2010 and 2023. The study was carried out within the framework of a universal school-based prevention program targeting tobacco and electronic cigarette use, delivered during the first year of compulsory secondary education. Following the intervention, students voluntarily and anonymously completed an evaluation questionnaire. Trends in experimentation across cohorts and associations between self-reported program participation and psychosocial and program evaluation variables were examined using logistic regression models and interpreted as observational associations without causal attribution.

Experimentation with conventional cigarettes showed a marked decline in the earlier cohorts and a subsequent stabilization in more recent years. Electronic cigarette use was assessed from 2021 onwards, with relevant prevalence levels observed in the most recent cohorts. In the subsample with detailed consumption data (n = 2,206), electronic cigarettes were the most commonly used product in the past 30 days (10.4%), followed by conventional cigarettes (7.2%).Social exposure to tobacco use was high, with more than 80% of students reporting at least one smoker in their immediate environment. In bivariate regression analyses, self-reported participation in the program was associated with experimentation with electronic cigarettes (OR = 0.66; p = 0.006), although this association did not remain significant after adjustment for age, gender, school type, and social exposure. By contrast, program participation showed consistent associations with indicators of program evaluation, including positive appraisal of the sessions (AOR = 5.25; 95% CI: 3.85-7.16) and discussion of program content within the family (OR = 1.92; p < 0.001).

In this repeated cross-sectional series, adolescent use patterns were characterized by the increasing prominence of electronic cigarettes. Self-reported program participation was associated with indicators of engagement and appraisal, which should be interpreted within the limits of the observational design. Overall, the findings highlight the relevance of prevention approaches that explicitly address vaping and integrate school-based actions with adolescents' social and family contexts.

High-diversity ecosystems are often presumed to be resilient. Yet, marine caves, along with other high-diversity systems, have proved highly sensitive to both climate change and anthropogenic stressors. This study seeks to resolve the underlying causes of this apparent paradox by investigating the functional resilience of marine caves ecosystems. We investigated nine Atlantic marine caves to identify key environmental drivers at landscape, local, and within-cave scales of sessile community structure and assess their functional resilience. Using hierarchical sampling (414 photoquadrats, 126 taxa), biological trait analysis (six traits), and statistical modelling (RLQ-Fourth Corner, GLMs, GAMMs), we assessed trait-environment relationships. Wave energy was the dominant driver among seascape and local-scale factors, explaining 34.5% of trait-environment associations, followed by depth range (7.7%). Four functional syndromes reflected major ecological trade-offs, such as autotrophs vs. active sponge feeders. Despite high regional taxonomic diversity (Shannon H' = 3.6) and functional richness (1.93), 57% of functional entities were represented by single taxa revealing low functional redundancy and thus low resilience potential. Functional vulnerability decreased and redundancy increased with spatial scale, with semi-dark zones being the most vulnerable cave sector (81%). Overall, wave exposure and depth shaped functional structure and resilience potential at a seascape scale in marine caves. The decoupling between taxonomic diversity and functional redundancy suggests that this vulnerability paradox may be a common pattern in high-diversity systems, as demonstrated in coral reefs and tropical forests, partially explaining their unexpected fragility under global change.

Microforamina are small vascular channels connecting the cranial diploe to the endocranial space, hypothesized to play a role in thermoregulation and neuroimmune functions, yet their quantitative anatomy is poorly documented in humans and, in general, in vertebrates. This preliminary study provides the first analysis of their number, size, and correlation with skull thickness in 10 modern human crania, using high-resolution industrial tomography (0.25 mm voxel size). Results show substantial interindividual variability, with an inverse relationship between channel size and frequency. Although the smallest channels were most numerous, the larger ones contributed to a comparable total luminal area. Medium-sized channels show statistically significant correlations with cranial thickness: negative correlations with inner table thickness and positive correlation with diploic space proportion, specifically in the parietal and occipital bones. These preliminary findings establish a quantitative baseline, indicating that microforamina prevalence is more influenced by the thickness of the vault layers than with general cranial size.