Articles

C-phycocyanin (C-PC) is a high-value pigment–protein in <i>Spirulina</i> biomass whose thermolability makes it vulnerable to degradation during post-harvest drying, yet freeze-drying—the gold-standard preservation method—remains prohibitively energy-intensive for large-scale production. This study investigated whether controlled-humidity air drying can preserve C-PC content and its antioxidant functionality in dried biomass comparably to freeze-drying. Wet <i>Spirulina</i> biomass (25 g fresh weight) was dried under nine factorial combinations of temperature (25, 40, and 60°C) and relative humidity (20, 30, and 40%) using a temperature–humidity chamber, with freeze-drying (FD) as the reference. C-PC was extracted, quantified spectrophotometrically along with allophycocyanin and chlorophyll, and its purity index (A<SUB>620</SUB>/A<SUB>280</SUB>) and antioxidant activity (DPPH radical scavenging, IC<SUB>50</SUB>, and ascorbic acid equivalent antioxidant capacity) were determined. Statistical analyses included one-way ANOVA with Tukey's post-hoc test and partial Pearson correlation. Air drying at 25°C yielded C-PC contents of 184.39 - 194.72 mg g<SUP>-1</SUP> DW (98 - 104% of the FD reference, 188.11 mg g<SUP>-1</SUP> DW) with food-grade purity indices of 0.95 - 1.00, whereas drying at 40°C and 60°C reduced C-PC to 76 - 85% and 58 - 63% of the FD value, respectively. Partial correlation analysis identified temperature as the dominant determinant of C-PC loss (Pearson <i>r</i> = -0.90 to -1.00), while relative humidity exerted a secondary, modulatory influence. The 25°C air-dried C-PC retained 86 - 87% of the antioxidant capacity of a commercial C-PC reference standard, approaching the 94% retention achieved by freeze-drying. These findings demonstrate that controlled-humidity air drying at 25°C and 20 - 30% relative humidity effectively preserves both C-PC yield and bioactivity at levels comparable to freeze-drying, offering a potential scalable and low-cost drying alternative for the <i>Spirulina</i> nutraceutical industry

The focus of this study was to determine the influence of religious literacy and multicultural teaching competence on the teaching self-efficacy of Religious and Moral Education (RME) teachers in public basic schools within the Kumasi Metropolis. The research employed a cross-sectional survey design with a sample of 308 RME teachers selected through the stratified sampling technique from 165 basic schools across 14 circuits. Data were collected using questionnaires and analysed using Partial Least Squares Structural Equation Modelling (PLS-SEM). The findings revealed that religious literacy significantly and positively influenced teachers’ self-efficacy (β = 0.487, p < 0.05), accounting for 23.7% of the variance. Similarly, multicultural teaching competence demonstrated a strong positive effect on teaching self-efficacy (β = 0.711, p < 0.05), explaining 50.6% of the variance. Finally, the study found that religious literacy and multicultural teaching competence together contributed 52.2% to RME teachers' teaching self-efficacy (SD = 0.692, p < 0.05, R² = 0.522). The study recommended that the Ghana Education Service (GES) and the National Council for Curriculum and Assessment (NaCCA) should design and mandate regular in-service training programmes focused specifically on religious literacy for RME teachers. Also, it was recommended that pre-service and in-service training should emphasise awareness of personal biases, deep knowledge of learners’ cultural and religious backgrounds, and practical skills for culturally responsive pedagogy.

The construction industry remains one of the most hazardous sectors globally, with Nigeria experiencing a high incidence of workplace accidents despite the adoption of Occupational Health and Safety Management (OHSM) frameworks. This study evaluated the effectiveness of OHSM practices in improving workplace safety across construction companies in Nigeria’s coastal cities. A cross-sectional design was employed, combining quantitative surveys of construction workers (n = 1,400) with qualitative interviews of 35 managers and supervisors. Quantitative data were analyzed using SPSS version 28, while thematic analysis was applied to qualitative responses. Findings revealed a generally positive perception of OHSM, with 54.4% of workers rating OHS policy effectiveness as “Good” and 52.0% rating health outcomes as “Good.” However, accident frequency remained a concern, with 46.4% reporting accidents occurred “Occasionally” and 31.9% acknowledging them as “Frequent” or “Very Frequent.” Comparative analysis showed indigenous firms were rated higher in policy effectiveness and health outcomes but also reported slightly higher accident frequencies than international firms. Thematic analysis identified five key monitoring and evaluation strategies including routine inspections, regular training, audits, behavioural reinforcement, and access control, Also, five measures of OHSM effectiveness, including compliance observation, incident tracking, KPIs, employee feedback, and benchmarking. OHSM was found to positively influence project outcomes by reducing compensation costs, enhancing reputation, and improving supervision and quality of work. OHSM practices in Nigeria’s construction sector are perceived as effective in policy and health outcomes, yet accident rates remain a critical challenge. The study underscores the importance of continuous training, stricter enforcement, behavioural reinforcement, and systematic performance evaluation.

<b>Introduction:</b> Stroke remains one of the leading causes of death and disability worldwide, with ischemic stroke accounting for most cases. Structural vascular factors such as carotid artery tortuosity have gained attention as potential markers of vascular aging and cerebrovascular risk. The carotid tortuosity index (CTI), defined as the ratio of actual vessel length to the straight-line distance between two fixed points, provides a quantitative measure of arterial curvature. A CTI value of ≥1.2 indicates pathological tortuosity. Although noninvasive modalities such as CTA and MRA are frequently used, digital subtraction angiography (DSA) remains the gold standard for evaluating vessel geometry due to its higher spatial precision. This study aimed to determine the association of age, sex, and hypertension with CTI measured by DSA.<b> </b><b>Methods:</b> A cross-sectional study was conducted from November to December 2025 at the Neurointervention Clinic, RS Pelni Jakarta, Indonesia, involving 61 adult patients who underwent carotid DSA. CTI was measured bilaterally using digital imaging software and classified as <1.2 (non-tortuous) or ≥1.2 (tortuous). Clinical data, including age, sex, and hypertension status, were collected from medical records and analyzed using bivariate tests. <b>Results:</b> Older age (≥65 years), female sex, and hypertension were significantly associated with higher CTI values on both carotid sides. Tortuosity was more common among hypertensive patients and elderly females, indicating the influence of vascular remodeling and chronic hemodynamic stress. <b>Conclusion:</b> Carotid tortuosity increases with age, hypertension, and female sex. DSA-based CTI measurement provides a reliable and precise approach for evaluating vascular changes associated with cerebrovascular risk.

The ultimate goal of this study was to determine the influence of religious literacy and multicultural teaching competence of RME teachers on their teaching self-efficacy in the Accra Metropolis. Grounded in culturally responsive teaching and self-efficacy theory, this study employed a cross-sectional survey design. All 441 RME teachers in the eight (8) circuits in the Metropolis which has seventy-two (72) basic schools were involved in the study through the census method. Data were collected using a questionnaire and analyzed using descriptive statistics and partial least squares structural equation modeling (PLS-SEM). Findings revealed that RME teachers reported high levels of RL, MTC, and TSE. Religious literacy and multicultural teaching competence jointly explained 44.2% of the variance in TSE, with a statistically significant positive effect (p < 0.05). It was recommended that, the curriculum for training RME teachers should include in them topics on RL and MTC.

Eating at home remains very much ingrained in Ghanaian culture but rapid urbanization coupled with busy lifestyle and advancement in technology has greatly changed the way of life of many Ghanaians. These changes have altered the tradition of cooking and eating at home. The study focused on the determinants of consumer patronage of street foods in the Koforidua Metropolis. The target population comprised customers that patronize the street foods in Koforidua Metropolis. From the target population, 197 consumers were selected using convenience. A structured self-administered questionnaire was utilized to gather the required data. The data collected were coded and analyzed with the help of SPSS-23. The findings revealed that food characteristics and social status determines consumers patronage of street food. It became evident that age (r=0.261, p<0.01), age (r=-0.318, P<0.01), educational level (r=0.144, P<0.05) and occupation (r=-0.477, P<0.01) of consumers has a significant influence on the decision and patronage of street food. The study concluded that food characteristics and social factors are major determinants of consumers patronage of street foods. It is recommended that Food and Drug Authority (FDA), other stakeholders, and street food vendors work cooperatively to establish laws that capture the distinctive and diverse foods sold on the street and their various preparation, storage, and sale methods in order to ensure that food preparation and sales are safe and hygienic.

Frequent consumption of aflatoxins-contaminated spices has been linked to serious adverse health effects among consumers. The likelihood of exposure to these toxins is influenced by the level of public awareness. Controlling aflatoxins contamination throughout the food chain is critical for public health. This study aimed to assess the handling practices and awareness of aflatoxin contamination among micro- and small-scale spice processors. A total of 60 processors from 4 districts of two regions of Tanzania were interviewed. The results showed that while 56.7% of interviewed processors were aware of aflatoxin contamination in spices primarily through training (38.3%) and mass media (30%). However, there were still misconceptions regarding the causes and effects of aflatoxins to human health. It was observed that, poor drying and storage practices, inadequate monitoring of processors aggravated the situation. Nonetheless, all interviewed processors expressed willingness to participate in training programs to ensure quality and safety along the chain. The study findings underscore the necessity for targeted interventions to reduce aflatoxin risks in the spice value chain. These should include strengthened food safety inspections and enforcement, as well as tailored training and support for micro and small-scale spice processors. Enhancing their knowledge and ability to adopt proper handling, drying and storage practices is critical for enhancing food safety and safeguarding public health.

<b>Background:</b><b> </b>Traditional foods, once carriers of cultural identity and heritage, are being quietly replaced as globalization and modern ideals redefine the choices of younger generations. This ethnographic study investigated the cultural meaning and symbolism of <i>Tuei</i>, an indigenous maize-based beverage, among the Fante people in the Central Region of Ghana. The study aimed to document how <i>Tuei</i> is rooted in Fante social and ceremonial life, exploring its role as a symbol of identity, continuity, and tradition. <b>Methods:</b> A qualitative approach with semi-structured interviews were done with 7 participants involving one cultural expert, three elders, and three local producers. <b>Results:</b> The findings revealed that <i>Tuei</i> has a significant role in rites of passage such as marriages, funerals, and naming ceremonies, where it functions as a marker of status and social cohesion. It was daily used as a gesture of hospitality and symbol of community unity. Additionally, the study found that the nutritional benefits of <i>Tuei</i> was rich in essential nutrients from maize, which contribute to energy provision and digestion. Some participants also reported its traditional use in promoting digestive health and general well-being. Again, <i>Tuei</i> was influenced by modernization which has reduced its consumption among younger generations and elite groups. <b>Conclusions:</b> The study concluded with recommendations to strengthen these preservation efforts through educational initiatives, the integration of <i>Tuei</i> into cultural festivals, and ongoing community engagement to ensure the continuity of this cultural practice.

The gut-brain axis (GBA) has emerged as a central focus in the study of neurodevelopmental disorders, particularly autism spectrum disorder (ASD). Research suggests that microbial composition and its metabolic byproducts influence neural development, synaptic plasticity, and behavior [1,2,3]. A structured bibliometric analysis of Scopus and Web of Science records was performed using Bibliometrix and VOSviewer to trace trends and thematic evolution of GBA–ASD literature [7,8]. In parallel, a data-driven pathway modeling approach maps microbial metabolites (e.g., short-chain fatty acids, tryptophan catabolites) to host signaling pathways including vagal stimulation, immune cytokine modulation, and blood–brain barrier (BBB) permeability [4,5]. Simulations implemented in Python’s NetworkX illustrate how perturbations in metabolite flux may influence CNS outcomes. The findings reveal growing emphasis on butyrate, serotonin, microglial priming, and maternal immune activation in ASD-related GBA studies, and highlight the need for rigorous empirical validation of computational predictions [9,10,11].

<b>Background:</b> Sexual and gender minority (SGM) youth are at elevated risk for adverse mental health and substance use outcomes. Stressors such as family conflict, discrimination, and trauma have been suggested as possible mediators of these disparities. <b>Aims:</b> This study examined whether family conflict, discrimination, and trauma mediate the associations between SGM identity and adverse outcomes, including suicide attempt, major depressive disorder (MDD), nicotine use, and marijuana use. <b>Methods:</b> Participants were children from the Adolescent Brain Cognitive Development (ABCD) study. SGM identity was reported at baseline, while outcomes included past MDD and suicide attempts as well as future nicotine and marijuana use. Structural equation modeling (SEM) was used to test both direct and indirect pathways linking SGM identity to mental health and behavioral outcomes. <b>Results:</b> No significant mediation was found through family conflict, discrimination, or trauma. Instead, effects of SGM identity were primarily direct: SGM youth had higher odds of past suicide attempts and MDD, as well as future marijuana use, but not future nicotine use. Stressor variables, however, were independently associated with outcomes. Discrimination predicted all outcomes; trauma was positively associated with suicide, nicotine, and marijuana use but not MDD; and family conflict predicted all outcomes except MDD. <b>Conclusion:</b> Family conflict, discrimination, and trauma did not mediate SGM disparities in mental health and substance use, but each emerged as an independent predictor of risk. These findings highlight the complexity of mechanisms underlying SGM-related disparities and suggest the need for future research to explore additional pathways and contextual influences.

This commentary letter was conducted to evaluate Wang et al.'s (2025) research study on the relationship between perceived staffing and quality of care among hospitals. The current study's findings show that the relationship between professional self-efficacy and job performance is mediated by work engagement. Life contentment influences work engagement, which is associated with enhanced job performance. However, involvement acts as a mediator between job performance and burnout, which could affect the quality of patient care. Staffing satisfaction and quality patient care are closely related, and it is essential for healthcare institutions to prioritize appropriate workforce levels and address the nursing shortage. However, there are still unanswered questions in this sector, such as researching nursing-specific care procedures, addressing data challenges, and understanding the connections between nursing practice and patient care outcomes. Future research should address the "black box" of nursing practice and address variations in the quality of patient care provided by nurses.

The Free Senior High School (FSHS) policy implementation in Ghana has garnered significant attention in academic research, with various studies delving into its advantages and implementation obstacles. Nevertheless, there has been a rise in school dropout rates among secondary school students amidst the programme implementation. There is therefore the need for a more localized scientific inquiry into the socio-economic factors contributing to school dropout among Senior High School (SHS) students in the Abofour community. The study employed a qualitative approach, using the case study design to conduct interviews with 22 students who had dropped out of SHS, to explore their experiences and identify key socio-economic factors influencing their decisions to leave school. Thematic data analysis revealed six main themes, namely, lack of parental support, peer influence, early marriage and pregnancy, economic conditions, and unsupportive school environment, as among the causative factors. The findings suggest that while the Free SHS policy has removed some direct financial barriers, other social, economic, and institutional factors continue to spur up dropout rates. The study concludes that addressing these underlying issues requires a multi-faceted approach that includes strengthening family support systems, improving school environments, and providing targeted interventions for at-risk students. In this regard, policymakers and other educational stakeholders are required to provide targeted supports to enhance student retention and reduce dropout rates in the Abofour community.

<b>Background:</b> Adolescent girls living in disaster-prone coastal regions of Bangladesh face heightened nutritional vulnerability due to limited food access, poor dietary diversity, and environmental stressors. Despite growing concerns about adolescent malnutrition, few studies have examined the combined influence of food security, dietary diversity, and age on nutritional outcomes in these settings. <b>Objectives:</b> This study aimed to assess the association between dietary diversity, food security, and age with the nutritional status of adolescent girls in coastal Bangladesh. <b>Methods:</b> A cross-sectional survey was conducted among 345 adolescent girls aged 10–19 in Chattogram and Cox’s Bazar. Data on dietary intake were collected using a 24-hour dietary recall and a food frequency questionnaire. Household food security was assessed using a validated scale. Nutritional status was determined using BMI-for-age classifications. Bivariate and multivariate analyses explored associations between dietary diversity, food security, age, and nutritional status. <b>Results:</b> Among participants, 10.14% were underweight, and 29.85% were either overweight or obese. While 17.39% demonstrated high dietary diversity (≥7 food groups), the majority had moderate diversity (5 or 6 food groups) (59.42%). Food-insecure households were significantly more likely to have overweight or obese adolescents (p < 0.05). Although dietary diversity was associated with BMI in bivariate analysis, it was not a significant predictor in the multivariate model. Age showed a significant relationship with both dietary diversity and nutritional status. <b>Conclusion:</b> The findings emphasize the importance of addressing household food security and age-related nutritional vulnerabilities in coastal areas. Interventions should prioritize age-sensitive, culturally appropriate strategies to improve dietary quality and prevent the double burden of malnutrition among adolescent girls.

<b>Objective:</b> This integrative review aims to critically examine the clinical management of periprosthetic joint infections (PJI) in total hip arthroplasty (THA), emphasizing decision-making strategies, diagnostic advancements, and therapeutic innovations. The study focuses on the complexity of infection control, microbial resistance, and individualized treatment planning. <b>Methods:</b><b> </b>A systematic review of the literature was conducted using PubMed, Scopus, Web of Science, and Google Scholar, targeting studies published between 2015 and 2025. Articles were selected based on their contribution to understanding the clinical, microbiological, and surgical aspects of PJI in THA. Fifty-five studies met the inclusion criteria and were analyzed descriptively.<b> </b><b>Results:</b><b> </b>PJI in THA is influenced by multifactorial risk profiles, including obesity, diabetes, and immunosuppression. Staphylococcus aureus, particularly MRSA, remains the most frequently isolated pathogen, followed by Gram-negative organisms and fungal species. Diagnostic innovations such as next-generation sequencing have enhanced pathogen detection, while two-stage revision remains the gold standard for chronic infections. Emerging strategies—such as antimicrobial coatings, tailored antibiotic protocols, and multidisciplinary care models—demonstrate promise in improving clinical outcomes. <b>Conclusion:</b><b> </b>Managing PJI in THA necessitates a comprehensive and individualized approach, integrating early and accurate diagnosis, pathogen-specific treatment, and advanced preventive measures. The integration of emerging technologies and personalized care pathways is critical to optimizing outcomes and reducing the clinical and economic burden of PJI.

(1) <b>Background</b>: Psychological flexibility, the ability to adapt to changing demands while staying true to personal values, is linked to better health behaviors. However, its relationship with cardiovascular health behaviors, particularly in Filipino populations, remains underexplored. (2) <b>Aim</b>: This study aimed to examine the relationship between psychological flexibility and cardiovascular health behaviors among outpatients in Rizal, Philippines, focusing on BMI, smoking, physical activity, and dietary habits. (3) <b>Methods</b>: A cross-sectional, descriptive-correlational design was used with 100 outpatient participants from selected hospitals. Psychological flexibility was measured using the Acceptance and Action Questionnaire-II (AAQ-II), and cardiovascular health behaviors were assessed using a modified version of the American Heart Association’s Life Simple 7 tool. Descriptive statistics and Pearson’s correlation were applied. (4) <b>Results</b>: The findings showed that respondents had neutral levels of psychological flexibility. While most exhibited intermediate BMI and physical activity, dietary habits varied. A significant positive correlation was found between psychological flexibility and whole grain consumption. However, no significant associations were found with BMI, smoking, or physical activity. (5) <b>Conclusions</b>: Psychological flexibility appears to influence specific health behaviors, such as dietary choices, but does not strongly correlate with other cardiovascular health behaviors. Further research is needed to explore its broader role in cardiovascular disease prevention.

<b>Background</b><b>:</b><b> </b>Electronic cigarette (e-cigarette) use is increasingly prevalent among youth and young adults, particularly college and university students. This is a population for whom e-cigarette use is not recommended due to potential health risks, including nicotine addiction and long-term respiratory effects. Social networks play a crucial role in shaping attitudes toward e-cigarettes and influencing use behaviors. However, the relative influence of different social ties—parents, siblings, and friends—on e-cigarette attitudes and use remains unclear. <b>Objective</b><b>:</b><b> </b>This study utilizes data from the SMOKES study to compare the influence of e-cigarette use within different social network sections—parents, friends, and siblings—on personal e-cigarette attitudes and use among college and university students. <b>Methods</b><b>:</b><b> </b>Using a cross-sectional survey of college and university students, we examined the associations between e-cigarette use within different social networks and individual e-cigarette attitudes and use. Multivariate regression models assessed the strength of these associations, adjusting for key demographic and behavioral covariates. <b>Results</b><b>:</b><b> </b>Findings indicate that among college and university students, the strongest influence on both e-cigarette attitudes and use comes from friends who use e-cigarettes. In contrast, parental and sibling e-cigarette use showed weak or non-significant effects. These results suggest that peer influence, rather than family influence, plays a dominant role in shaping e-cigarette-related behaviors and perceptions in young adults. <b>Conclusion</b><b>:</b><b> </b>This study underscores the importance of peer influence in e-cigarette uptake and attitudes among college and university students. Public health interventions aimed at reducing e-cigarette use in this population should consider targeting peer networks rather than focusing solely on family-based influences.

<b>Background: </b>Electronic cigarette (e-cigarette) use and vaping tobacco have increased rapidly worldwide, raising concerns about their health effects, social acceptability, and regulatory challenges. In many countries, e-cigarettes are more commonly used by individuals from higher socioeconomic status (SES) backgrounds, who, in theory, should have greater knowledge about e-cigarettes and their associated risks. However, it remains unclear why a group with more knowledge about e-cigarette risks would also hold more positive attitudes toward vaping and exhibit higher usage rates — a phenomenon that may represent a knowledge-behavior paradox. Understanding this paradox, along with the complex relationships between e-cigarette knowledge, attitudes, and behaviors, is critical for informing effective public health interventions, campaigns, social media messaging, and regulatory policies. <b>Objectives: </b>This study aimed to evaluate the complex relationship between SES, e-cigarette knowledge, pro-vaping attitudes, and e-cigarette use. <b>Methods: </b>The SMOKES Study (Study of Measurement of Knowledge and Examination of Support for Tobacco Control Policies) used a multi-center, cross-sectional design, collecting data from 2,403 college and university students across 15 provinces in Iran (covering nearly half of the country's provinces). The survey measured family income, age, sex, ethnicity, e-cigarette use, knowledge, and attitudes. Structural Equation Modeling (SEM) was employed to examine the interrelations between SES, knowledge, attitudes, and behavior, while adjusting for age, sex, and ethnic minority status. <b>Results</b>: SEM analysis confirmed the hypothesized paradox. Although greater knowledge about e-cigarettes was linked to less favorable attitudes toward vaping and lower use, pro-vaping attitudes emerged as the strongest predictor of vaping behavior, while knowledge played a weaker protective role. Notably, individuals with higher SES simultaneously showed higher knowledge and, paradoxically, more pro-e-cigarette attitudes and greater usage. Female students and ethnic minority students reported higher correct knowledge and lower pro-vaping attitudes and use. Although age and higher family income were associated with more favorable attitudes, they did not directly predict vaping behavior. These results suggest that for higher SES individuals, poor knowledge is not the main driver of e-cigarette use; rather, their pro-e-cigarette attitudes, which seem to outweigh the influence of knowledge, play a key role. <b>Conclusions: </b>Although individuals from higher SES backgrounds report greater correct knowledge about e-cigarettes, this knowledge does not necessarily translate into reduced positive attitudes or lower usage. This study highlights the complexity of these paradoxical effects and suggests that public health strategies need to go beyond simple education and knowledge-based interventions. Targeted approaches should address industry messaging, challenge misconceptions, and strengthen regulatory efforts to reduce e-cigarette use among young adults, including those from higher SES backgrounds.

<b>Background:</b> Women have consistently shown lower quit rates in tobacco cessation programs compared to men. This gender disparity persists despite comprehensive interventions and access to cessation resources. While prior studies suggest that factors such as social support, chronic disease burden, and socioeconomic status may contribute to these differences, there is limited empirical evidence to confirm these mechanisms. <b>Aims:</b> This study aimed to investigate potential mechanisms underlying gender differences in quit rates in a tobacco cessation program, testing whether demographic, socioeconomic, health, or behavioral factors explain the observed disparities. <b>Methods:</b> Participants were assigned to one of three smoking cessation interventions: an in-person program (CEASE), a self-help approach, or an online/hybrid program. The main outcome measured was smoking abstinence, evaluated three months after the intervention. Secondary analyses explored whether demographic, socioeconomic, health, or tobacco use-related factors mediated the association between gender and quit rates. <b>Results:</b> Women had significantly lower quit rates than men (p < 0.01). This association remained significant after adjusting for demographic, socioeconomic, health, and addiction-related factors. While women reported higher social support and a higher prevalence of chronic cardiometabolic conditions, these factors did not explain the gender disparity in quit rates. <b>Conclusions:</b> Gender differences in quit rates persist despite controlling for known factors that could influence cessation success. Although women had higher social support, they had lower quit rate. Future research should explore unmeasured variables, such as psychological, biological, and structural influences, to develop more effective cessation strategies tailored for women.

<b>Background: </b>The hippocampus plays a critical role in memory and decision-making processes, with its resting-state functional connectivity (rsFC) linked to various behavioral outcomes. This study investigates whether baseline brain-wide rsFC of the hippocampus mediates the relationship between impulsivity and subsequent substance use, specifically tobacco and marijuana use, in adolescents. <b>Methods: </b>Data were drawn from the baseline wave of the Adolescent Brain Cognitive Development (ABCD) study. Resting-state fMRI data were used to evaluate the functional connectivity of the hippocampus with key brain networks, including the cingulo-parietal network, visual network, sensory-motor network, and default mode network (DMN). Impulsivity was assessed using validated self-report measures, and substance use (tobacco and marijuana) was evaluated at follow-up. Mediation models were conducted to examine the extent to which hippocampal rsFC explains the association between impulsivity and substance use. <b>Results: </b>Baseline hippocampal rsFC with the cingulo-parietal network, visual network, sensory-motor network, and DMN showed marginal associations with future tobacco and marijuana use. Additionally, hippocampal rsFC was significantly associated with impulsivity, which, in turn, predicted higher substance use at follow-up. These findings suggest that hippocampal rsFC partially mediates the relationship between impulsivity and substance use behaviors. <b>Conclusions: </b>Hippocampal functional connectivity with brain networks may influence the pathway from impulsivity to future substance use in adolescence. These findings emphasize the importance of hippocampal connectivity in understanding the neural mechanisms underlying risk behaviors and may inform the development of targeted interventions to reduce substance use in this vulnerable population.

<b>Background</b><b> </b>Adolescent substance use is often influenced by socioeconomic and geographical factors. While higher parental education is typically associated with lower substance use, these protective effects may be weaker for marginalized groups facing structural disadvantages that limit the utility and returns of their economic and social resources. Rural areas, characterized by fewer employment opportunities and limited recreational activities, may contribute to marginalization-related diminished returns (MDRs) of parental education on adolescent substance use, including inhalant use. <b>Objectives</b><b> </b>This study applies the MDRs framework to examine whether the protective effect of higher parental education on current inhalant use (past 30 days) among 12th-grade American adolescents varies by geographic location. Specifically, we assess whether youth from highly educated families in rural areas are at a disproportionate risk of inhalant use compared to their urban and suburban peers. <b>Methods</b><b> </b>Using data from the 2024 Monitoring the Future (MTF) study, a nationally representative survey of 12th-grade adolescents in the U.S., we tested main effects and statistical interactions between parental education and residence (rural vs. urban/suburban) in predicting the odds of inhalant use over the past 30 days. Logistic regression models, both with and without interaction terms, were applied to evaluate whether the protective effects of parental education varied by residence location, controlling for relevant demographic and socioeconomic factors. <b>Results</b><b> </b>Findings indicate a significant interaction between parental education and rural residence. While higher parental education was associated with lower odds of inhalant use in urban and suburban areas, this protective effect was substantially weaker in rural settings. Adolescents from highly educated families in rural areas exhibited a higher-than-expected risk of inhalant use, suggesting that geographic marginalization attenuates the benefits of parental socioeconomic resources. <b>Conclusions</b><b> </b>These results highlight the role of place-based marginalization in shaping adolescent substance use disparities, demonstrating that MDRs extend beyond race and ethnicity to location-based disadvantages. Rural youths from highly educated families may face unique structural and social challenges that counteract the protective effects of parental education. Public health efforts should consider place-based interventions that address the economic, recreational, and social limitations of rural environments to reduce substance use risk among high-SES adolescents residing in rural areas.