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Bayesian hierarchical modelling of root canal morphology in mandibular first premolars across 21 countries
Pertek Hatipoğlu, Fatma; Magat, Güldane; Karobari, Mohmed Isaqali; Buchanan, Glynn Dale; Kopbayeva, Maira; Taha, Nessrin; Makahleh, Nisrein; Fernández-Grisales, Rafael; Bekjanova, Olga; Luu, Peter; Bürklein, Sebastian; Mufadhal, Abdulbase; Petridis, Xenos; Mora, María Fernanda; Sugumaran, Surendar; Allawi, Safaa; Ivica, Anja; Lim, Wen Yi; Fadag, Abdulrahman; Jagtap, Rohan; Martín-Cruces, José; Kulczyk, Tomasz; Alfirjani, Suha; Palma, Paulo J.; Hatipoğlu, Ömer (Wiley, 2026)
BACKGROUND : Understanding root canal morphology is crucial for successful endodontic treatment; however, the anatomy of mandibular first premolars (M1Ps) remains one of the most variable and challenging aspects. The Vertucci classification provides a standardised framework for describing canal configurations; however, population-level data integrating multiple countries are scarce. This study aimed to evaluate the global distribution and determinants of Vertucci canal morphology in M1Ps using a Bayesian hierarchical model. METHODS : Cone-beam computed tomography (CBCT) data of M1Ps from 21 countries were analysed. The Vertucci classification was used as the categorical outcome variable. The predictors included tooth side (34/44), voxel size, field of view (FOV), sex and age, with the country modelled as a random intercept. A Bayesian hierarchical multinomial logistic regression was fitted using the brms package (rstan backend) with weakly informative priors. Posterior estimates were expressed as odds ratios (OR) and 95% credible intervals (CrI), and model-based predicted probabilities were computed for each Vertucci type. RESULTS : Bayesian modelling estimated the posterior probability of Vertucci Type I configuration at 73.4% (95% CrI: 63.8%–81.5%). Non–Type I configurations showed lower but credible probabilities, including Type V (8.2%, 3.6%–15.9%), Type III (3.7%, 1.6%–7.7%), Type IV (2.9%, 1.2%–6.3%) and Type II (1.3%, 0.5%–3.1%). Unclassified canal patterns accounted for approximately one-tenth of the MnP1s (9.9%, 3.9%–19.2%). Substantial variability was observed between countries for non–Type I and unclassified configurations, whereas Type I remained consistently predominant. Sex and age exerted modest effects, whereas tooth side and field of view showed no meaningful associations. Increasing the voxel size was associated with a slight reduction in the probability of Type I and marginal increases in Type V and unclassified configurations. CONCLUSIONS : Although Vertucci Type I configuration predominates globally in MnP1s, clinically relevant non–Type I and unclassified canal patterns occur with non-negligible frequency and vary across populations. Bayesian hierarchical modelling enables the robust quantification of anatomical heterogeneity and uncertainty, supporting more reliable cross-country comparisons and cautious interpretation of less common canal configurations.
Availability and affordability of therapies and services of multiple sclerosis in Africa : a continent-wide survey
Shalash, Ali; Gams Massi, Daniel; Ben Sassi, Samia; Tibar, Houyam; Fall, Maouly; Zewde, Yared Z.; Alsiddig Ebraheem, Ahmed; Mecheri, Yasser; Razafimahefa, Julien; Dadah, Samy; Fernando, Goncalves Carlos; Kapto, Olivier; Kisekka Musubire, Abdu; Sheikh Mohamed, Ahmed Omar; Camara, Massaman; Nestor, Nsengiyumva; Amer, Naziha; Neshuku-Nampala, Saara Ndinelago; Marcellin, Bugeme; Sakad, Foksouna; Ngwende, Gift Wilson; Hooker, Juzor; Jamnagerwalla, Yusuf; Akpalu, Albert; Saylor, Deanna; Van Coller, Riaan; Okubadejo, Njideka U.; Hamid, Eman; Abdelaziz, Azza Abdelnasser; Salah, Nouran Mohamed (Sage, 2026-03)
BACKGROUND : Limited data is available about the availability of multiple sclerosis (MS) therapies and services in Africa. OBJECTIVE : We aimed to investigate the availability, affordability, frequency of usage, and insurance coverage of MS therapies and services across Africa. METHODS : A comprehensive web-based survey was constructed and distributed to neurologists from different African countries. The survey addresses availability, affordability, frequency of use, and insurance coverage of different therapies and services of MS. RESULTS : Respondents represented 27 African countries. Intravenous methylprednisolone was always available in most countries (88.9%), while interferons were completely or partially available in 13 countries (48.1%). The most available disease-modifying therapies (DMTs) were rituximab (22 countries, 81%), followed by interferon beta 1a intramuscular type (12, 44.4%). Availability of other DMTs was variable, while specific MS services were limited. Affordability is limited in most countries, and the use of DMTs was related to insurance coverage. Most associated therapies and investigations were more available and affordable, but less insured. Neurologists were the main healthcare providers, but traditional healers had a role in 14.8% of countries. CONCLUSION : Significant challenges characterize MS care in Africa. MS therapies, particularly DMTs and services, are inaccessible and unaffordable in most African countries.
Boosting hydrogen evolution reaction performance via island effect-driven interfacial charge tuning and bubble kinetics optimization on Co/Ni(OH)2 array electrode
Jiang, Runlai; Wang, Zheng; Ma, Xianguo; Wang, Xuyun; Song, Hongbing; Wang, Hui; Li, Zihao; Ren, Jianwei; Wang, Rongfang (Elsevier, 2026-01)
Please read abstract in the article.
Bodyguard interactions : a beneficial endophyte triggers emission of methyl salicylate in infested tomato plant mediating attraction of a parasitoid wasp
Akutse, Komivi S.; Agbessenou, Ayaovi; Yusuf, Abdullahi Ahmed; Khamis, Fathiya Mbarak (Springer, 2026-03-13)
The endoparasitoid Dolichogenidea gelechiidivoris is a potential candidate biocontrol agent of Phthorimaea absoluta. We previously reported that the endophyte Trichoderma asperellum M2RT4 triggers the systemic release of key phytohormones in tomato affecting the behavior and herbivory of P. absoluta. As D. gelechiidivoris uses odor cues to locate P. absoluta, we therefore investigated the chemical basis of interactions between D. gelechiidivoris, the tomato plant with and without endophyte and P. absoluta through bioassay-guided chemical analysis. Y-tube olfactometer bioassays showed that the parasitoid was significantly attracted to P. absoluta-infested tomato plants but did not show preference to colonized and colonized-infested plants. Coupled GC–MS analyses revealed both qualitative and quantitative differences in volatile emission between non-colonized, colonized, non-colonized infested and colonized-infested plants, where volatile emission rate increased with increasing infestation level. Methyl salicylate (MeSA) emission was significantly higher in colonized-infested than in colonized and non-colonized infested plants. Subsequent bioassays revealed attraction of the parasitoid to synthetic MeSA emitted at its natural release rate from endophytically-colonized infested plants. Our findings highlight the significant role played by MeSA, which mediates the attraction of D. gelechiidivoris thereby indirectly assisting tomato plants in combatting P. absoluta.
Self-perception changes in adults post-hearing aid adoption
Ferreira, Sulette; Poonasamy, Kaylan; Warren, McKayla; Young, Tamaryn-Ann (University of Pretoria, 2025-10)
Background: Despite their proven benefits for communication, hearing aids continue to show low adoption and use among individuals with hearing loss who require intervention. Various audiological factors contribute to these outcomes; however, limited research has explored the psychosocial aspects that influence hearing aid adoption and use, which could have important implications for rehabilitation strategies. Objective: This study aimed to explore changes in self-perception experienced by adults following hearing aid adoption. Method: A qualitative design was followed to thematically analyse retrospective interview responses from 42 adult participants. Participants were recruited using the Hearing Tracker and Lexie Hearing databases in the United States. Results: Participant ages ranged from 40 to 84 years (mean=70.2 years; 8.2 SD). The majority of participants were male (n=20; 66.7%), and most participants were unilateral hearing aid users (n=27; 90%). Five main themes emerged: self-awareness, overall communication, social engagement, improved quality of life, and work performance. Within these main themes, 13 sub-themes emerged, where participants described a range of positive experiences, such as greater acceptance of hearing loss, heightened confidence, and increased participation. At the same time, some negative experiences were also reported, including perceptions of no noticeable change, as well as persistent communication and hearing difficulties. Conclusion: Hearing aid adoption may support improvements in self-awareness, hearing ability, and participation in everyday life, contributing to predominantly positive changes in self-perception in adults. Although hearing aids play an important role in enhancing psychosocial outcomes, challenges still remain due to unmet expectations or limited benefits in some situations. These findings emphasise the importance and the need for holistic hearing rehabilitation and counselling to communicate both the benefits and limitations of hearing aid use in clinical settings.