title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=149 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Knowledge, attitudes, practices, and vaccination coverage of medical students toward hepatitis B virus in North Sudan, 2023 link: https://peerj.com/articles/18339 last-modified: 2025-01-02 description: BackgroundHepatitis B virus (HBV) is a global health issue, particularly among healthcare personnel, including students because of its occupational exposure pattern. Healthcare Workers and medical students are recommended to have better knowledge, attitudes and good practices and vaccination toward infection control in general and HBV in particular. This study aimed to assess the knowledge, attitudes, and practices of medical students from North Sudan regarding HBV and its vaccination coverage.MethodsA cross-sectional study was conducted from January to June 2023 among medical students in North Sudan. Data were collected using a structured scale using online Google Forms. Descriptive and comparative analyses were performed using SPSS version 26. Statistical significance was set at p ≤ 0.05.ResultsA total of 426 medical students were included in the study. The majority had good knowledge about HBV (86%) and its transmission methods (77%). The majority showed a favorable attitude (77%). The practice score was however very low (15.5%). Older age and advanced academic level were significantly associated with good knowledge (aOR: 3.9; CI 95% [3.69–12.92]; p = 0.016, and aOR: 2.6; CI 95% [1.16–6.15]; p = 0.020, respectively). Only a third of the students were vaccinated (33.0%), with only a few of them received complete doses (18.6%).ConclusionStudents from medical colleges in North Sudan had good knowledge and favorable attitudes toward HBV. However, good practice was low. Older age and advanced academic level were significantly associated with knowledge level. Vaccination coverage was also low among the students in this study. creator: Osama M.I. Mohamed creator: Hassan S.H. Mohammedali creator: Shimaa N.A. Mohamed creator: Hussein A.S. Ahmed creator: Alaa A.M. Mohamedsalih creator: Ola M.A. Abdalgani creator: Tebian A.A. Mohammedosman creator: Alaa A.A. Ali creator: Thuiba A.H. Ali creator: Othman N.O. Amin creator: Mohamed A. Issak creator: Mohamed O. Abdelaziz uri: https://doi.org/10.7717/peerj.18339 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Mohamed et al. title: Constructing age-structured matrix population models for all fishes link: https://peerj.com/articles/18387 last-modified: 2025-01-02 description: Matrix population models are essential tools in conservation biology, offering key metrics to guide species management and conservation planning. However, the development of these models is often limited by insufficient life history data, particularly for non-charismatic species. This study addresses this gap by using life history data from FishBase and the FishLife R package, complemented by size-dependent natural mortality estimates, to parameterize age-structured matrix population models applicable to most fish species. The method was applied to 30 fish species common around oil and gas platforms in the Northern Gulf of Mexico, generating seven key metrics: damping ratio, resilience, generation time, stable age distribution, reproductive value, sensitivity matrix, and elasticity matrix. The damping ratio reflects how quickly a population returns to a stable age distribution after a disturbance, while resilience indicates the speed of recovery from perturbations. Generation time captures the average age of reproduction, and the stable age distribution represents the long-term proportion of individuals in each age class. Reproductive value quantifies future reproductive potential by age class. The sensitivity matrix highlights the age-class transitions most affecting population growth, and the elasticity matrix shows the proportional influence of these factors on population growth. The results demonstrate that robust population models can be constructed with limited species-specific data and reveal notable differences in population dynamics among species. For example, species with longer generation times, like the greater barracuda (Sphyraena guachancho), have lower damping ratios, indicating prolonged transient dynamics. In contrast, species such as the round scad (Decapterus punctatus) exhibit shorter generation times and higher damping ratios, suggesting faster returns to equilibrium. These findings underscore the importance of life history variability in shaping conservation strategies. Additionally, metrics like stable age distributions and reproductive values provide insight into population structure and individual contributions to future populations, while sensitivity and elasticity matrices inform management interventions such as size limits in fisheries. By integrating extensive databases and predictive tools, this study offers a scalable approach for developing matrix population models across diverse fish species. This methodology enhances our understanding of fish population dynamics, particularly for data-deficient species, and supports more informed conservation efforts. It also promotes ecosystem-based management by enabling species comparisons through standardized metrics, contributing to the sustainability of marine ecosystems. creator: Masami Fujiwara uri: https://doi.org/10.7717/peerj.18387 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Fujiwara title: Mapping species of greatest conservation need and solar energy potential in the arid Southwest for future sustainable development link: https://peerj.com/articles/18568 last-modified: 2025-01-02 description: The need for renewable energy has become increasingly evident in response to the climate change crisis, presenting a paradoxical challenge to biodiversity conservation. The Southwest United States is desirable for large-scale solar energy development (SED) due to its high global horizontal irradiance (GHI) values and vast open landscapes. However, this region is also rich in unique ecological and biological diversity. Several distinct species have garnered special attention as human population growth, habitat alteration, and climate change have accelerated in recent decades (i.e., LeConte’s Thrasher (Toxostoma lecontei), Bendire’s Thrasher (Toxostoma bendirei), Sonoran Desert Tortoise (Gopherus morafkai), Mojave Desert Tortoise (Gopherus agassizii), and the Southwestern population of the Burrowing Owl (Athene cunicularia). As the United States prepares to increase its development in renewable energies, particularly solar energy, there has been a growing concern about how this development will further impact these species. In this study, we propose a novel combined approach to find areas of high habitat suitability for endangered species within areas of high SED potential. Specifically, we employed species distribution modeling (SDM) to identify areas with suitable habitats and likely species presence, and we conducted a site suitability analysis for potential SED locations within the Southwest. As a result, we found significant overlap between potential SED locations and the high-priority habitats of all target species, thus underlining the importance of prioritizing conservation efforts as more solar projects are reviewed in these Southwestern states. Our study aims to inform conservationists and developers in making sustainable decisions for the region’s future development. creator: Kylee Fleckenstein creator: Adam Stein creator: Heather L. Bateman creator: Fabio De Albuquerque uri: https://doi.org/10.7717/peerj.18568 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Fleckenstein et al. title: A giant specimen of Rhamphorhynchus muensteri and comments on the ontogeny of rhamphorhynchines link: https://peerj.com/articles/18587 last-modified: 2025-01-02 description: Rhamphorhynchus is one of the best-known pterosaurs, with well over 100 specimens being held in public collections. Most of these represent juvenile animals, and the adults known are typically around 1 m in wingspan. Here we describe a near complete skeleton, preserved partially in 3D, of an animal with a wingspan of around 1.8 m, that is considerably larger than other known specimens, and is among the largest known non-pterodactyloid pterosaurs. This animal shows differences in the anatomy not seen in smaller specimens, revealing details of late-stage ontogeny in this genus. The specimen exhibits a disproportionate reduction in the size of the orbit and increase in the size of the lower temporal fenestra, a reduction in the proportional mandibular symphysis, and unusually laterally flattened teeth, which may point to a changing diet as these animals grew. These features show a transition from smaller to larger specimens of Rhamphorhynchus and also appear in other large specimens of rhamphorhyhchines and point to a consistent pattern in their development. creator: David W.E. Hone creator: Skye N. McDavid uri: https://doi.org/10.7717/peerj.18587 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Hone and McDavid title: The application of deep learning in early enamel demineralization detection link: https://peerj.com/articles/18593 last-modified: 2025-01-02 description: ObjectiveThe study aims to develop a diagnostic model using intraoral photographs to accurately detect and classify early detection of enamel demineralization on tooth surfaces.MethodsA retrospective analysis was conducted with 208 patients aged 14 to 44. A total of 624 high-quality digital images captured under standardized conditions were used to construct a deep learning model based on the Mask region-based convolutional neural network (Mask R-CNN). The model was trained to automate the detection of enamel demineralization. Its performance was compared to two junior dentists’ diagnostic abilities.ResultsThe model achieved an F1-score of 0.856 for detecting demineralized teeth on the validation set, a metric that reflects comprehensive diagnostic performance, demonstrating performance close to that of senior dentists. With the the model’s assistance, the junior dentists’ average F1-scores improved significantly—from 0.713 and 0.689 to 0.897 and 0.949, respectively (p < 0.05). The model accurately segmented tooth surfaces and detected demineralized areas, allowing for precise detection of demineralized areas and monitoring of lesion progression.ConclusionDeep learning can accurately segment tooth surfaces and lesion contours, enhancing the precision, accuracy, and efficiency of enamel demineralization diagnosis and area delineation. creator: Ketai He creator: Rongxiu Zhang creator: Muchun Liang creator: Keyue Tian creator: Kaihui Luo creator: Ruoshi Chen creator: Jianpeng Ren creator: Jiajun Wang creator: Juan Li uri: https://doi.org/10.7717/peerj.18593 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2025 He et al. title: The inter-trial and inter-session reliability of Theia3D-derived markerless gait analysis in tight versus loose clothing link: https://peerj.com/articles/18613 last-modified: 2025-01-02 description: BackgroundGait analysis is traditionally conducted using marker-based methods yet markerless motion capture is emerging as an alternative. Initial studies have begun to evaluate the reliability of markerless motion capture yet the evaluation of different clothing conditions across sessions and complete evaluation of the lower limb and pelvis reliability have yet to be considered. The aim of this study was to evaluate the inter-trial, inter-session and inter-session-clothing variation and root mean square differences between tight- or loose-fitting clothing during walking.MethodTwenty-two healthy adult participants walked along an indoor walkway whilst eight video cameras recorded their gait in either tight- or loose-fitting clothing. A commercial markerless motion capture system (Theia3D) provided gait kinematics for evaluation.ResultsReliability results showed average inter-trial variation of <2°, inter-session variation of <3° and inter-session-clothing variation <3.5°. Root mean square differences (RMSD) between clothing conditions were <2°.DiscussionPelvis variations were smaller than those at the hip, knee and ankle. Our results showed smaller variation than in previous studies which may be due to updates to software. The demonstration of the reliability of markerless motion capture for gait analysis in healthy adults should prompt further evaluation in clinical conditions and reconsideration of multi-assessor marker-based gait analysis protocols, where variation is highest. creator: Sylvia Augustine creator: Richard Foster creator: Gabor Barton creator: Mark J. Lake creator: Raihana Sharir creator: Mark A. Robinson uri: https://doi.org/10.7717/peerj.18613 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Augustine et al. title: How many reptile and amphibian species are in Uganda, and why it matters for global biodiversity conservation link: https://peerj.com/articles/18704 last-modified: 2025-01-02 description: Biodiversity is unevenly distributed across the globe. Regional differences in biodiversity impact conservation through the allocation of financial resources, development of infrastructure, and public attention. Such resources are often prioritized to areas that are in more need than others. However, reasons for deciding which locations are more deserving are derived from an accurate knowledge of the number and composition of species that occur in each region. Regional differences in biodiversity, however, can reflect differences in the source of information consulted, rather than bona fide differences between areas. As a result, conservation resources may not be directed to regions in proportion to their actual need, especially if there is no consensus among sources of information. Here, we compared major sources of information on species of reptiles and amphibians that occur in Uganda, Africa. We found that none of the sources agreed on the total number, nor composition, of species in the country, with estimates for amphibians ranging more widely than those for reptiles. Notably, sources with similar species richness differed in species composition, which had an impact on the number of threatened species in the country. These results for a conspicuous group of vertebrates suggest that lesser-known groups are also likely misrepresented in sources, especially in other underexplored regions of tropical Africa. We discuss the implications for biodiversity conservation that are derived from inaccurate species lists that are commonly used by agencies, scientists, and practitioners. We argue that more critical evaluations of biodiversity resources, in addition to greater capacity building for field programs, taxonomy, and museum collections, will be essential to ensure that resources are allocated to regions that need them the most. creator: Daniel F. Hughes creator: Mathias Behangana uri: https://doi.org/10.7717/peerj.18704 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Hughes and Behangana title: Basis of single-seed formation in chestnut: cytomorphological observations reveal ovule developmental patterns of Castanea henryi link: https://peerj.com/articles/18711 last-modified: 2025-01-02 description: BackgroundMany plants, including those commonly found in the Fagaceae family, produce more flowers and ovules than mature fruits and seeds. In Castanea henryi, an ovary contains 16–24 ovules, but only one develops into a seed. The other ovules abort or otherwise fail to fully develop, but the reason for this is unknown. Such a strict reproductive screening mechanism is rare in plants.MethodsIn this study, controlled pollination scheme were adopted, and conventional paraffin embedding and semi-thin sectioning techniques, followed by microscopy, were used for cytological studies of ovule development in C. henryi.ResultsPollination affected not only the process of ovule development, but also the proportion of ovules that formed mature embryo sacs. Approximately 53.53% of the ovules in the pollinated treatment developed normally, while only 16.55% of the ovules in the unpollinated treatment developed into mature embryo sacs with a seven-cell, eight-nucleated structure. Failure to form mature embryo sacs and the abnormal divisions of the zygote, respectively, were the reasons for the pre- and post-fertilization ovule failures. Our findings not only provide basic information on the reproductive biology and also information on seed production of C. henryi. creator: Qi Qiu creator: Xiaoming Tian creator: Guolong Wu creator: Juntao Wu creator: Deyi Yuan creator: Xiaoming Fan uri: https://doi.org/10.7717/peerj.18711 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2025 Qiu et al. title: Effect of low-dose radiation pre-irradiation on postoperative local chest wall recurrence of breast cancer—A retrospective study link: https://peerj.com/articles/18717 last-modified: 2025-01-02 description: PurposeThe purpose of this study was to determine the efficacy and safety of low-dose radiotherapy (LDR) for postoperative local chest wall recurrence of breast cancer.MethodsThe records of 52 patients with postoperative local chest wall recurrent breast cancer treated at our cancer center from January 2019 to December 2022. The t-test was used to compare the means of the LDR group and non LDR group. Categorical data were compared using the chi-square test. The Kaplan-Meier method were used to determine the factors associated the survival.ResultsCompared to patients who did not undergo LDR, patients in the LDR group showed a higher incidence of grade I side effects in their skin and soft tissue systems (p = 0.002), a significant reduction in grade II side effects (p < 0.05), and no grade III side effects. Compared with the non LDR group, the complete response rates were 42.3% vs. 38.5%, p = 0.777, the partial response rates were 53.8% vs. 50.0%, p = 0.781, and the objective relief rates were 96.2% vs. 88.5%, p = 0.833, respectively. The 3-year overall survival rate, local recurrence free survival rate, distant metastasis-free survival rate and disease-specific survival rate comparison between LDR group and non LDR group was 54.8% vs. 55.8%, p = 0.845 and 54.2% vs. 52.9%, p = 0.751, 67.9% vs. 51.9%, p = 0.097 and 39.2% vs. 49.6%, p = 0.993, respectively.ConclusionCompared with traditional radiotherapy, LDR pre-irradiation has better tolerance and efficacy in patients with local chest wall recurrence of breast cancer after operation. creator: Ruifang Zeng creator: Hanyu Wang creator: Xiaojun Cai creator: Junhao Lin creator: Pengfei Li creator: Shan Zeng creator: Aimin Li uri: https://doi.org/10.7717/peerj.18717 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2025 Zeng et al. title: Visualizing and quantifying biomineral preservation in fossil vertebrate dental remains link: https://peerj.com/articles/18763 last-modified: 2025-01-02 description: In this study, we attempt to illustrate fossil vertebrate dental tissue geochemistry and, by inference, its extent of diagenetic alteration, using quantitative, semi-quantitative and optical tools to evaluate bioapatite preservation. We present visual comparisons of elemental compositions in fish and plesiosaur dental remains ranging in age from Silurian to Cretaceous, based on a combination of micro-scale optical cathodoluminescence (CL) observations (optical images and scanning electron microscope) with in-situ minor, trace and rare earth element (REE) compositions (EDS, maps and REE profiles), as a tool for assessing diagenetic processes and biomineral preservation during fossilization of vertebrate dental apatite. Tissue-selective REE values have been obtained using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), indicating areas of potential REE enrichment, combined with cathodoluminescence (CL) analysis. Energy dispersive X-ray spectroscopy (EDS) mapping was also used to identify major elemental components and identify areas of contamination or diagenetic replacement. We conclude that the relative abilities of different dental tissues to resist alteration and proximity to the exposure surface largely determine the REE composition and, accordingly, the inferred quality of preserved bioapatite. creator: Matthew B. Cowen creator: Marc de Rafélis creator: Loïc Ségalen creator: Benjamin P. Kear creator: Maïtena Dumont creator: Živilė Žigaitė uri: https://doi.org/10.7717/peerj.18763 license: https://creativecommons.org/licenses/by-nc/4.0 rights: © 2025 Cowen et al.