Exploring the impact of visual stimuli on taste expectations and the role of pull-tab position in food packaging
Background Preference for an image is often associated with the perceived ease of use of the depicted object. Aim This study investigated the impact of visual stimuli on taste expectations, focusing on the presentation of food in images. Specifically, it explored how the presence of a pull-tab—perceived by participants as a tool that makes the product easy to use or open—influences these expectations. Methods A sample of 42 right-handed university students (30 women, 12 men; mean age = 20.4 years) evaluated perceived taste expectations of food presented under different conditions using a 9-point Likert scale. The conditions included images of canned food (“Can condition”) with varying pull-tab positions (0°, 90°, 180°, 270°, and Down), as well as images of actual food (“Pineapple condition”). Each participant was shown 12 images per trial in a randomized order and rated their taste expectations immediately after viewing each image. Statistical analyses were conducted using linear mixed models and ANOVA using the Kenward-Roger method. Results Taste expectations were significantly lower in the Can condition compared with the Pineapple condition (mean difference = 3.14, SE = 0.23, p < 0.001). Within the Can condition, pull-tab positions had a significant effect on taste expectation ratings (F = 116.94, p < 0.001). The 0° position (pull-tab facing the viewer) received the highest rating (M = 4.87, SD = 1.86), while the 180° position (pull-tab facing away) received the lowest (M = 3.95, SD = 1.73). Conclusion These findings underscore the complex relationship between visual presentation and taste expectations, providing valuable insights for optimizing product presentation in marketing strategies.
Shibuya et al. (2025) Exploring the impact of visual stimuli on taste expectations and the role of pull-tab position in food packaging. PeerJ 13:e20417 https://doi.org/10.7717/peerj.20417
Metabolites of traffic-related volatile organic compounds in age-related macular degeneration
Background Volatile organic compounds (VOCs), commonly emitted from vehicle exhaust and industrial activities, are prevalent air pollutants in urban environments. These compounds have been reported to cause various health effects through mechanisms such as oxidative stress and neurotoxicity. Recently, air pollution has attracted attention as a potential risk factor for age-related macular degeneration (AMD); however, the association between VOC exposure and AMD remains unclear. Objective This study aimed to assess VOC exposure levels among urban-dwelling AMD patients by quantifying urinary metabolites and investigating the association between VOCs and AMD. Methods This cross-sectional study included 40 untreated AMD patients (AMD group), 10 cataract patients (Cataract group), and 10 healthy controls (Healthy group). Representative urinary metabolites of VOCs—2-methylhippuric acid, 3-methylhippuric acid, mandelic acid, phenylglyoxylic acid, and trans,trans-muconic acid—were measured using gas chromatography-mass spectrometry (GC/MS), with concentrations corrected for urinary creatinine. Group comparisons were performed based on creatinine-adjusted metabolite levels. Results The AMD group exhibited elevated urinary VOC metabolite levels compared to both control groups. The ratios of mean concentrations in the AMD group versus the Healthy and Cataract groups, respectively, were: 2-methylhippuric acid (201% and 181%), 3-methylhippuric acid (190% and 139%), mandelic acid (304% and 198%), phenylglyoxylic acid (118% and 90%), and trans,trans-muconic acid (214% and 92%). Among these, 2-methylhippuric acid and mandelic acid were significantly higher in the AMD group than in both controls (p < 0.001 and p = 0.042; p < 0.001, respectively). Trans,trans-muconic acid also showed a significant increase compared to the Healthy group (p < 0.001). Correlation analysis within the AMD group revealed moderate but significant associations for 2-methylhippuric acid (r = 0.29, p = 0.011), mandelic acid (r = 0.47, p < 0.001), and trans,trans-muconic acid (r = 0.27, p = 0.020). Multivariate logistic regression identified mandelic acid as an independent factor significantly associated with AMD (odds ratio = 17.20, p < 0.001). Subgroup analysis categorized the AMD group into drusenoid AMD, typical AMD (t-AMD), polypoidal choroidal vasculopathy (PCV), and retinal angiomatous proliferation (RAP). No significant differences in urinary VOC metabolite levels were observed among the four subtypes after multiple comparison adjustment. Conclusions These findings indicate that AMD patients are exposed to higher levels of traffic-related VOCs. While mandelic acid—a styrene metabolite—was independently associated with AMD, its role should be interpreted as a potential exposure marker rather than a definitive disease biomarker. Further longitudinal studies are warranted to clarify causal relationships between VOC exposure and AMD development.
Mimura et al. (2025) Metabolites of traffic-related volatile organic compounds in age-related macular degeneration. PeerJ 13:e20405 https://doi.org/10.7717/peerj.20405
Virtual reality technology for upper and lower limb motor function, daily function, and balance in stroke patients: a meta-analysis of randomized controlled trials
Background Stroke is a common neurological disorder that often results in motor dysfunction, significantly impairing patients’ quality of life and increasing the economic burden on healthcare systems. Virtual reality (VR) technology has emerged as an innovative approach in stroke rehabilitation. This meta-analysis aimed to comprehensively evaluate the effects of VR-based interventions on motor function, daily function, and balance in stroke patients. Methods We systematically searched PubMed, Embase, the Cochrane Library, Web of Science, and China National Knowledge Infrastructure (CNKI) databases from inception to October 2025 for randomized controlled trials (RCTs) investigating VR technology in stroke rehabilitation. Study quality was assessed using the Cochrane Risk of Bias 2.0 tool. Data synthesis involved pooling effect sizes, conducting subgroup analyses, and assessing publication bias using Stata 17. Results A total of 27 RCTs involving 877 stroke patients were included in the meta-analysis. VR technology demonstrated statistically significant improvements across multiple functional domains: lower limb motor function (Cohen’s d = 0.41, 95% CI [0.25–0.57], P < 0.001), upper limb motor function (Cohen’s d = 0.25, 95% CI [0.03–0.48], P = 0.03), daily function (Cohen’s d = 0.24, 95% CI [0.07–0.42], P = 0.01), and balance (Cohen’s d = 0.31, 95% CI [0.09–0.52], P < 0.001). The effects ranged from small to moderate across domains, with lower limb function showing the most substantial improvement. Sensitivity analyses confirmed the robustness of these findings, and subgroup analyses revealed that factors such as training cycle influenced treatment effects. Conclusion VR technology demonstrates significant potential as an effective complementary intervention for improving motor function, daily function, and balance in stroke patients. The small to moderate effect sizes across domains support its integration into conventional rehabilitation protocols. Future research should focus on optimizing VR parameters, investigating different VR technology types, and evaluating long-term sustainability to further establish its efficacy in stroke rehabilitation.
Zhang et al. (2025) Virtual reality technology for upper and lower limb motor function, daily function, and balance in stroke patients: a meta-analysis of randomized controlled trials. PeerJ 13:e20402 https://doi.org/10.7717/peerj.20402
Metabolite profiling from the fermentation of marine-derived extracts by Lactobacillus acidophilus LB
Background Lactobacillus acidophilus LB is a probiotic strain with the ability to produce valuable bioactive metabolites through fermentation. Sustainable biomass sources such as Spirulina platensis, Ulva reticulata, and Caulerpa lentillifera, which can also be obtained from agricultural or aquacultural by-products, offer a promising alternative for microbial cultivation, but their effects on the metabolic profile of L. acidophilus LB are still unclear. Methods The study utilized L. acidophilus LB (GenBank accession OK398226) cultivated in media containing Spirulina platensis, Ulva reticulata, and Caulerpa lentillifera extracts. High-resolution mass spectrometry (liquid chromatography-high resolution mass spectrometry-quadrupole-time-of-flight, LC-HRMS QTOF) was employed for compound profiling. Principal component analysis (PCA) and Pearson correlation were used to analyze metabolic variations across different culture conditions. The Kruskal-Wallis test assessed statistical differences in metabolite concentrations. Results Methyl lucidenate Q and 6-Gingerol were the most abundant bioactive compounds detected across samples. PCA revealed that L. acidophilus LB in media supplemented with different preparations of Spirulina platensis, Ulva reticulata, and Caulerpa lentillifera was associated with distinct differences in metabolite profiles, leading to clustering patterns. K-means clustering identified three metabolomic groups, with the pellet obtained from L. acidophilus LB cultured in medium supplemented with U. reticulata seaweed showing a unique chemical profile. Pearson correlation analysis suggested possible biochemical interactions among metabolites, with Auraptenol and Daturametelin B exhibiting a strong positive correlation (r = 0.99). The absence of Methyl lucidenate Q in this sample indicates potential enzymatic degradation or metabolic inhibition. Conclusion This study highlights the impact of L. acidophilus LB on metabolite diversity in substrate-driven fermentation systems. The findings suggest microbial interactions modulate metabolite patterns in the fermented supernatants, potentially enhancing pharmacological properties. Future research should focus on optimizing culture conditions to maximize yield and functional validation of identified compounds for therapeutic applications. These insights contribute to the broader field of natural product discovery and marine biotechnology.
Hoang et al. (2025) Metabolite profiling from the fermentation of marine-derived extracts by Lactobacillus acidophilus LB. PeerJ 13:e20399 https://doi.org/10.7717/peerj.20399
Athletic participation and its impact on self-concept, body image, and physical fitness in Saudi female adolescents: a cross-sectional comparison between athletes and non-athletes
Background Adolescence is a critical developmental period marked by significant physical and psychosocial changes that shape adult behavior and personality. In Saudi Arabia, where female sports participation is newly encouraged, this study therefore aimed to explore how athletic participation influences body image perception, including potential discrepancies between self-perception and fitness outcomes, in a context where female participation in structured physical activity has historically been limited but is now being promoted under Vision 2030. Methods A cross-sectional study was conducted in Riyadh province from October 2024 to February 2025, involving 439 female students aged 12–18. Participants were recruited from schools in Al Majma’ah city and were categorized as athletes (school sports participants, n = 252) or non-athletes (n = 241). Outcomes were assessed using the Physical Self-Inventory-Short (PSI-S) for self-perception, the Stunkard Scale for body image, and physical performance tests (Shuttle Run, V Sit-and-Reach, and Wall Sit Test). Results Our findings revealed that athletes reported significantly higher self-perception on the PSI-S compared to non-athletes (53.17% vs. 37.34% high self-perception; p = 0.002). After body mass index (BMI) adjustment, athletes scored higher on the Stunkard Scale (5.83 vs. 4.31; p < 0.001). Athletes demonstrated a tendency to perceive their bodies as moderately larger than their actual BMI-adjusted size, a disparity not observed in non-athletes. This self-perception coexisted with superior physical performance, suggesting that athletic training may decouple size perception from functional capability. Athletes outperformed non-athletes in cardiorespiratory fitness (Shuttle Run: 9.96 vs. 8.01; p < 0.001), flexibility (V Sit-and-Reach: 14.50 vs. 13.02; p = 0.012), and muscular endurance (Wall Sit Test: 63.17 vs. 58.30; p = 0.024). No significant differences in self-perception were observed across BMI categories, suggesting athletic participation’s benefits transcend weight status. Conclusion The findings align with global research linking physical activity to enhanced body satisfaction and self-worth. However, athletes’ self-perception of larger body figures may reflect societal pressures toward thinness, highlighting the complex interplay of cultural ideals and body image. The study underscores the role of sports in promoting physical fitness and psychological well-being among Saudi adolescent females, supporting national efforts to encourage female athletic participation.
Alonazi et al. (2025) Athletic participation and its impact on self-concept, body image, and physical fitness in Saudi female adolescents: a cross-sectional comparison between athletes and non-athletes. PeerJ 13:e20353 https://doi.org/10.7717/peerj.20353
Bornean orangutan nest identification using computer vision and deep learning models to improve conservation strategies
Background Regular population surveys are crucial for the evaluation of conservation measures and the management of critically endangered species such as the Bornean orangutans. Uncrewed aerial vehicles (UAV) are useful for monitoring orangutans by capturing images of the canopy, including nests, to monitor their population. However, manually detecting and counting nests from UAV imagery is time-consuming and requires trained experts. Computer vision and deep learning (DL) models for image classification offer an excellent alternative for orangutan nest identification. Methods This study investigated DL for nest recognition from UAV imagery. A binary dataset (“with nest” and “without nest”) was created from UAV imagery from Sabah, Malaysian Borneo. The images were captured using a fixed-wing UAV with a complementary metal-oxide semiconductor camera. After image augmentation, 1,624 images were used for the dataset and further split into 70% training, 15% testing and 15% validation for model performance evaluation, i.e., accuracy, precision, recall and F1-score. Four DL models (InceptionV3, MobileNetV2, VGG19 and Xception) were trained to learn from the labeled dataset and predict the presence of nests in new images. Results The results show that out of four DL models, Inception V3 has the best model performance with more than 99% accuracy and precision, while VGG19 has the lowest performance. In addition, gradient-weighted class activation maps were used to interpret the results, allowing visualization of the regions used by InceptionV3 and VGG19 for classification. This study shows the potential of integrating DL into orangutan conservation, particularly in monitoring the orangutan population in the protected environment. Future research should focus on the automatic detection of nests to improve UAV-based monitoring of orangutans.
Simon et al. (2025) Bornean orangutan nest identification using computer vision and deep learning models to improve conservation strategies. PeerJ 13:e20333 https://doi.org/10.7717/peerj.20333
Identification of candidate long non-coding RNAs and mRNAs associated with heart aging in mice
Background Understanding the molecular mechanisms underlying cardiac aging may uncover novel therapeutic targets for age-related cardiovascular disease. Long non-coding RNAs (lncRNA), which regulate cell differentiation and disease progression, are emerging as promising diagnostic biomarkers and therapeutic candidates. However, their expression profiles and functional roles in the aging heart remain poorly characterized. Methods Male C57BL/6 wild type mice aged 20 months (aged group) and 3 months (young group) underwent transthoracic echocardiography to evaluate cardiac function. Myocardial aging phenotypes were assessed using hematoxylin-eosin, Masson’s trichrome, terminal deoxynucleotide transferase dUTP nick end labeling (TUNEL), and senescence-associated β-galactosidase staining. Transcriptomic profiling was performed using a lncRNA-focused microarray platform to identify differentially expressed lncRNAs and mRNAs in heart tissues. Results Aged mice showed increased heart weight/body weight and heart weight/tibia length ratios. Both interventricular septum in systole and left ventricular posterior wall in diastole were elevated, while ejection fraction and fractional shortening remained unchanged. The Tei index was significantly higher, suggesting impaired myocardial performance. Histological staining revealed enlarged cardiomyocytes, increased myocardial fibrosis, enhanced apoptosis, and greater senescence-associated β-galactosidase activity. Microarray analysis identified distinct age-related expression patterns of lncRNAs and mRNAs in the heart. Conclusions Cardiac aging is characterized by structural and functional remodeling, accompanied by transcriptional reprogramming involving both lncRNAs and mRNAs. These changes offer insights into potential molecular mechanisms and provide candidate regulatory targets for diagnosis and intervention in age-related heart disease.
Kuai et al. (2025) Identification of candidate long non-coding RNAs and mRNAs associated with heart aging in mice. PeerJ 13:e20433 https://doi.org/10.7717/peerj.20433
Evaluation of the retreatability of bioceramic root canal sealers with various formulations in simulated grooves
Background Bioceramic sealers are increasingly used due to their favorable properties, but their strong bonding to dentin complicates retreatment procedure. In addition, canal irregularities such as isthmuses make the complete removal of filling materials more challenging. Aim This study aimed to evaluate the retreatability of five bioceramic sealers (BioRoot RCS, Bio-C Sealer, CeraSeal, Endoseal MTA, and AH Plus Bioceramic Sealer) using passive ultrasonic irrigation. Materials and Methods Sixty human mandibular premolars with straight canals were prepared to size 40/0.04 taper. After longitudinal splitting, standardized grooves were created. The root canals were subsequently obturated using the single cone technique and stored at 37 °C with 100% humidity for 21 days. Passive ultrasonic irrigation was used to assess sealer removal. Statistical analysis was performed with Kruskal–Wallis and Mann–Whitney U tests. Results The amount of residual sealer in the apical region was statistically higher compared with the coronal region. In the coronal region, the highest amount of residual material was observed in the Bio-C Sealer group, and this difference was statistically significant compared to the other groups. There was no significant difference among the other groups. In the apical region, there were no statistically significant difference between Bio-C Sealer and Endoseal MTA; however Bio-C Sealer showed a statistically significantly higher amount of residual material compared to BioRoot RCS, Ceraseal, and Ah Plus Bioceramic Sealer. Conclusion Among the evaluated bioceramic sealers, Bio-C Sealer exhibited the highest amount of residual material, particularly in the apical region, indicating its lower retreatability. Passive ultrasonic irrigation improved the removal of BioRoot RCS, CeraSeal, and AH Plus Bioceramic Sealer, but was less effective for Bio-C Sealer and EndoSeal MTA. These findings highlight the variability in retreatability among different bioceramic sealers and emphasize the importance of material selection in cases with potential need for retreatment.
Sümbüllü et al. (2025) Evaluation of the retreatability of bioceramic root canal sealers with various formulations in simulated grooves. PeerJ 13:e20398 https://doi.org/10.7717/peerj.20398
Process of heavy metal transport between soil and the atmosphere: a review
The transport of heavy metals (HMs) (excluding Hg) between soil and the atmosphere significantly influences human production and life. This review systematically summarizes the processes involved in the wind erosion-driven transport of HMs from soil to the atmosphere and the partitioning of atmospheric HMs via atmospheric deposition, drawing on relevant literature analysis and synthesis. The results reveal that both soil and the atmosphere are sinks of HMs, influencing each other significantly. The transport of soil HMs to the atmosphere along with soil fugitive dust by wind force incorporates three pathways: the direct suspension of suspension-size aggregates, the collision and abrasion of creep-size and saltation-size aggregates, and the breakage or decomposition of creep-size aggregates. Conventional farming practices, elevated HM concentrations, and high wind speeds exacerbate soil HM emissions. However, the effects of soil organic matter (SOM) and clay on soil HM emission demonstrate dual characteristics. Atmospheric deposition has emerged as a significant source of soil HMs, with wet deposition predominating, except in arid and semiarid regions. Dry deposition is influenced by meteorological parameters and topographic profiles, whereas preceding weather and precipitation duration are other factors affecting for wet deposition. This process increases the exposure possibility and consequent exposure dosage of HMs to humans and crops, thereby amplifying the potential risks of HMs. Moreover, the capacity of atmospheric HMs for long-range wind-driven dispersal may leave remote and sensitive ecosystems that are increasingly vulnerable. Moreover, it concludes with a synthesis of the current challenges and discusses recommendations for future directions. Therefore, this review will have significant reference and guiding value for research in this field and is intended for researchers engaged in the migration of HMs in soil and atmosphere, the safe utilization of heavy metal contaminated soil, and regional background values of soil HMs.
Environmental Contamination and Remediation
Zhang et al. (2025) Process of heavy metal transport between soil and the atmosphere: a review. PeerJ 13:e20381 https://doi.org/10.7717/peerj.20381
Combined effect of Millet-Cowpea intercropping and biopesticide application against Heliocheilus albipunctella De Joannis (Lepidoptera: Noctuidae) in Burkina Faso
Pearl millet, Pennisetum glaucum L. R. Br. (Poales: Poaceae), the main cereal crop in the Sahelian zone of Burkina Faso, is attacked by several insect pests, among which is the millet head miner, Heliocheilus albipunctella De Joannis (Lepidoptera: Noctuidae). Damage and yield losses caused by H. albipunctella on millet range from 30.00% to 85.00%. Control and management of H. albipunctella currently rely on synthetic insecticides, which are harmful to human and environmental health. Hence, there is a need to explore and develop alternative management strategies. Consequently, the current research, which was conducted, explored the use of millet-cowpea intercropping, a very common practice in the Sahelian zone of Burkina Faso, together with the application of biopesticides of Neem (Azadirachta indica A. Juss. (Sapindales: Meliaceae) seed kernels aqueous extracts. Fieldwork was carried out in Burkina Faso’s Djibasso and Dori communes during the 2021 rainy period. The obtained results found that the application of Neem extracts on cowpea plants at the flowering stage, synchronized with the heading stage of millet, significantly reduced the incidence of H. albipunctella. When millet was intercropped with cowpea, the application of aqueous extracts of Neem indirectly led to a significant reduction of about 50.00% in the number of larvae per spike. Additionally, a reduction in the percentage of millet spikes attacked, a decrease in mine length, and a gain in grain yield of more than 40.00% were observed. Thus, the findings from the application of this agricultural practice could be a promising control option against H. albipunctella.
Boly et al. (2025) Combined effect of Millet-Cowpea intercropping and biopesticide application against Heliocheilus albipunctella De Joannis (Lepidoptera: Noctuidae) in Burkina Faso. PeerJ 13:e20221 https://doi.org/10.7717/peerj.20221