title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=25 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Geographic disparities and predictors of suicide mortality risk in Florida: spatial scan statistics and negative binomial modeling link: https://peerj.com/articles/20075 last-modified: 2025-11-04 description: BackgroundFlorida ranks 17th in suicide mortality risk in the United States, with 14.8 suicide deaths per 100,000 persons. Geographic disparities in suicide mortality across the US are well-documented and are partly attributed to the uneven distribution of risk factors. However, limited data exist on such disparities and associated predictors within Florida, despite their importance for guiding targeted prevention efforts. This study aimed to investigate county-level geographic disparities in suicide mortality risk in Florida and identify predictors of these disparities.MethodsThis retrospective ecological study used data from the Florida Department of Health. County-level age-adjusted suicide mortality risks and spatial empirical Bayesian-smoothed risks were calculated for three time periods: 2011–2013, 2014–2016, and 2017–2019. Tango’s spatial scan statistics were applied to identify high-risk clusters. A negative binomial regression model was used to examine county-level predictors of suicide mortality risk for the 2017–2019 period.ResultsStatewide age-adjusted suicide mortality risk increased from 22.6 to 24.3 per 100,000 persons over the study period. Counties in the northwest, northeast, southwest, and parts of central Florida consistently exhibited high mortality risks. Suicide mortality risk was significantly higher in counties with larger proportions of residents aged 45–64 years and ≥65 years, those reporting excessive drinking, frequent mental distress, or veteran status.ConclusionThis study identified geographic disparities and key predictors of suicide mortality risk across Florida counties. These findings can inform policymakers, healthcare providers, and community organizations in designing and implementing targeted suicide prevention programs tailored to the specific needs of high-risk communities. creator: Howard Onyuth creator: Corey Day creator: Nirmalendu Deb Nath creator: Agricola Odoi uri: https://doi.org/10.7717/peerj.20075 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Onyuth et al. title: Serum growth differentiation factor 15 trajectory predicts 28-day mortality in critically ill patients: a multicenter cohort study link: https://peerj.com/articles/20317 last-modified: 2025-11-03 description: BackgroundGrowth differentiation factor 15 (GDF15) has been linked to critical illnesses, particularly cardiovascular and infectious diseases, but its dynamic patterns and prognostic value in critically ill patients remain unclear. This study investigates the predictive utility of serum GDF15 trajectories for 28-day mortality among patients in the intensive care unit (ICU).MethodsIn this multicenter, prospective cohort study, ICU patients were enrolled, and serum GDF15 trajectories during the first week were analyzed using group-based trajectory modeling (GBTM). The association between trajectory subtypes and 28-day mortality was assessed through hierarchically adjusted multivariable logistic regression. A cumulative index, “GDF15-load,” was introduced to quantify overall GDF15 exposure and compared with the Acute Physiology and Chronic Health Evaluation II (APACHE II) and Sequential Organ Failure Assessment (SOFA) scores. The correlation between initial GDF15 levels (GDF15-D1) and GDF15-load was evaluated using Spearman’s correlation test. Predictive performance was assessed via the area under the receiver operating characteristic curve (AUROC), and feature importance was interpreted using Shapley Additive Explanations (SHAP).ResultsAmong 1,973 patients, 493 comprised the cohort for development with full serum profiles on days 1, 3, and 7. Four GDF15 trajectory subtypes were identified: low-maintenance (LM), medium-maintenance (MM), high-increase (HI), and high-persistent (HP). Trajectory subtypes showed significant differences in inflammatory markers, organ dysfunction, and 28-day mortality, with the HI and HP groups having the worst outcomes. GDF15-load increased progressively from LM to HP and emerged as the most important predictor of 28-day mortality, not inferior to APACHE II and SOFA scores. GDF15-D1 was strongly correlated with GDF15-load (Spearman r = 0.778) and demonstrated robust predictive value, particularly in postoperative ICU patients, where its combination with APACHE II or SOFA further improved prognostic accuracy.ConclusionsSerum GDF15 trajectory and GDF15-load are robust predictors of 28-day mortality in ICU patients. GDF15-D1 strongly reflects cumulative GDF15 burden and provides a rapid, practical tool for early risk stratification, especially in postoperative ICU patients. These findings support the use of GDF15 as both a dynamic and point-of-care biomarker in intensive care settings. creator: Qinxue Wang creator: Jiawei Wang creator: Yuhan Zhao creator: Yuanze Ma creator: Xiang Li creator: Xinyi Chang creator: Nan Zheng creator: Yong Ji creator: Yi Han uri: https://doi.org/10.7717/peerj.20317 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2025 Wang et al. title: Comparative dosimetric evaluation of single-beam dual-arc versus dual-beam single-arc volumetric modulated arc therapy strategies in lung stereotactic body radiotherapy using Monaco link: https://peerj.com/articles/20311 last-modified: 2025-11-03 description: Background and ObjectiveIn stereotactic body radiotherapy (SBRT) for lung cancer, the choice of volumetric modulated arc therapy (VMAT) optimization strategy is critical for achieving optimal target dose coverage while minimizing exposure to normal tissues. This study aims to compare the dosimetric performance and plan complexity of two VMAT optimization strategies in Monaco: single-beam dual-arc (1B2A) versus dual-beam single-arc (2B1A).MethodsA retrospective analysis was conducted on 50 lung cancer patients treated with SBRT (prescription dose: 50 Gy in 5 fractions). Two VMAT plans were re-optimized using the Monaco treatment planning system: the 1B2A plan (single-beam dual-arc, collimator angle 10°) and the 2B1A plan (dual-beam single-arc, collimator angles 10° and 350°). Dosimetric parameters, including target dose coverage, conformity index (CI), and gradient index (GI), were evaluated for the internal target volume (ITV) and planning target volume (PTV). Dose metrics for organs at risk (OARs) were also analyzed. Plan complexity was assessed based on monitor units (MU), number of control points, complexity index, and integral dose to normal tissues.ResultsSignificant dosimetric differences were observed between the two strategies. When normalized to ensure the prescribed 50 Gy isodose line covers 95% of the PTV volume, the high-dose parameters (D1%, D50%, Dmean) of the ITV and PTV were significantly lower in the 1B2A group compared to the 2B1A group (p < 0.001), indicating superior dose distribution with the 2B1A approach. Although the 1B2A plan exhibited marginally better CI, GI, and low-dose lung sparing (V5–V30), these differences were minimal and clinically insignicant. No substantial dierences were found in the dose sparing of other OARs, including the spinal cord, heart, and ribs. Additionally, the 1B2A plan required signicantly higher MU (+15.5%, p < 0.001) and had greater plan complexity (+9.47%, p < 0.001), suggesting lower treatment efficiency.ConclusionsIn peripheral lung cancer SBRT, the dual-beam single-arc (2B1A) strategy offers superior target dose distribution and treatment efficiency, making it a preferable optimization approach. creator: Jieni Ding creator: Yanqiu Huang creator: Qiang Li creator: Weijun Chen creator: Kainan Shao uri: https://doi.org/10.7717/peerj.20311 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Ding et al. title: A comparison of spinal and lower extremity biomechanics during maximal and sub-maximal deadlifts among strength-trained women link: https://peerj.com/articles/20279 last-modified: 2025-11-03 description: BackgroundPrevious studies have examined changes in biomechanical variables in response to different deadlift loads, yet, the effect of sub-maximal and maximal loads on potential deviation in lifting technique remain inadequately understood.MethodsTherefore, this study compared barbell and joint kinematics, net joint moments (NJMs), and surface electromyography (sEMG) amplitude during 70%, 90%, and 100% of three-repetition maximum (3RM) load using statistical parametric mapping. Twelve strength-trained women (age: 23.18 ± 3.46 years, height: 166.72 ± 2.90 cm, body mass: 68.18 ± 7.67 kg) lifted 72.5 ± 9.3 kg, 93.9 ± 16.6 kg, and 102.9 ± 17.6 kg s at 70%, 90%, and 100% of 3RM deadlifts, respectively.ResultsThe main findings revealed that the maximal load resulted in a significant increase in lower thoracic flexion angles and erector spinae sEMG amplitudes compared to the sub-maximal loads. Additionally, significantly lower hip NJMs were observed with a 70% load compared to 90% and 100% loads.ConclusionTherefore, increasing loads beyond 90% of 3RM might not be necessary if the goal is to train hip extensor strength through deadlifting. Deadlifting loads beyond 90% of 3RM may be achieved by increasing spinal flexion. This posture may allow strength-trained women to lift beyond the strength capacity of their hip extensors during the final repetition of a 3RM deadlift. creator: Andreas H. Gundersen creator: Roland van den Tillaar creator: Hallvard Falch creator: Stian Larsen uri: https://doi.org/10.7717/peerj.20279 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Gundersen et al. title: The role of pre-pregnancy overweight in gestational diabetes, hypertension, and macrosomia: a retrospective study link: https://peerj.com/articles/20277 last-modified: 2025-11-03 description: PurposeAdverse pregnancy outcomes, including gestational diabetes mellitus (GDM), gestational hypertension (GHp), macrosomia, preterm birth, and low birth weight, pose significant risks to maternal and neonatal health. Pre-pregnancy overweight is a modifiable risk factor for these outcomes. However, comprehensive analyses of multiple adverse outcomes and their dose-response relationships with pre-pregnancy body mass index (BMI) remain limited.MethodsThis retrospective cohort study included 748 women with singleton pregnancies who delivered at Yuyao Maternal and Child Health Hospital from January 1, 2022, to December 31, 2022. Participants were categorized into normal-weight and overweight groups based on pre-pregnancy BMI. Logistic regression models were used to evaluate associations between overweight and adverse pregnancy outcomes, adjusting for confounding variables. Restricted cubic spline (RCS) regression was employed to investigate dose-response relationships between BMI and pregnancy outcomes.ResultsPre-pregnancy overweight was significantly associated with higher risks of GDM (adjusted OR = 3.122, 95% CI [1.754–5.557], p < 0.001), GHp (adjusted OR = 2.864, 95% CI [1.566–5.239], p = 0.001), and macrosomia (adjusted OR = 2.119, 95% CI [1.076–4.173], p = 0.030). No significant associations were observed with preterm birth or low birth weight. RCS analysis showed no evidence of nonlinear relationships, indicating that the risk of adverse outcomes increased linearly with BMI.ConclusionPre-pregnancy overweight is a significant modifiable risk factor for adverse maternal and neonatal outcomes, particularly GDM, GHp, and macrosomia. These findings underscore the importance of integrating BMI monitoring and personalized weight management strategies into pre-pregnancy care programs to mitigate risks and improve maternal and neonatal health outcomes. creator: Sisi Zhu creator: LiFeng Chen creator: LiJuan Shen creator: Xiangxiang Fu uri: https://doi.org/10.7717/peerj.20277 license: https://creativecommons.org/licenses/by-nc/4.0 rights: ©2025 Zhu et al. title: Investigation of spatiotemporal evolution and driving mechanisms of carbon sources and sinks in dry-hot valleys under extreme climate events: a case study of the Nu River dry-hot valley link: https://peerj.com/articles/20268 last-modified: 2025-11-03 description: Under global climate change, the rising frequency of extreme weather events profoundly affects ecosystem carbon cycles. However, in the ecologically fragile dry-hot valleys of Southwest China, the response of carbon source-sink dynamics to these extremes remains unclear, which hinders effective regional carbon management. This study investigates the Nu River dry-hot valley, using the Google Earth Engine platform to process multi-source remote sensing and meteorological data from 2001–2024. We established a framework of 15 extreme climate indices and applied Sen-Mann-Kendall trend analysis, Pearson correlation, and threshold regression models to explore the spatiotemporal evolution of carbon dynamics and their non-linear response to extreme climate. Our results show that: (1) The region’s carbon sink capacity displayed a fluctuating but overall increasing trend with significant spatial heterogeneity; areas of substantial increase were concentrated in the southern, low-altitude zones. (2) Extreme climate events triggered non-linear carbon cycle responses by altering hydrothermal conditions. The synergy of high temperatures and intense, short-duration precipitation weakened the carbon sink, whereas dispersed rainfall alleviated drought stress and enhanced carbon fixation. (3) Both extreme temperature and precipitation indices showed clear regulatory thresholds, above which their effects were significantly amplified; this reveals that the carbon cycle in the dry-hot valley is highly sensitive to extreme events and exhibits distinct threshold-driven responses. This research provides a theoretical basis for the mechanisms regulating carbon flux in dry-hot ecosystems under a variable climate and offers crucial scientific support for optimising regional pathways to carbon neutrality and implementing climate-adaptive management. creator: Haojun Sun creator: Shaoyun Zhang creator: Shanshan Liu creator: Liping Zhang uri: https://doi.org/10.7717/peerj.20268 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Sun et al. title: From trace to trace maker: Oligocene–Miocene coprolites of southern Poland and their potential producers link: https://peerj.com/articles/20242 last-modified: 2025-11-03 description: In this paper we describe coprolites from deep-marine Oligocene sediments, shallow- and deep-marine Miocene deposits, as well as Miocene continental environments in southern and central Poland. The Oligocene and Miocene coprolites from marine environments (hereinafter referred to as M) are classified into six morphotypes: (M1) sinusoidal, (M2) elongated and straight, (M3) curved, (M4) irregular, (M5) S-shaped, and (M6) oval. Sinusoidal coprolites, previously interpreted as originating from predatory fish (e.g., Palimphyes, Oligophus, and indeterminate taxa), are reinterpreted here, based on actualistic observations, as crustacean (crab) faeces. Morphotypes (M2)–(M5) are attributed to fish, while the oval type (M6) is tentatively linked to columbid-like birds, although alternative producers cannot be excluded. Miocene deep-sea coprolites are represented by relatively long, complex fecal masses composed of constricted strings, suggesting holothurians or cephalopods as potential producers. Elongated Miocene coprolites from shallow-water environments are likely to have been produced by teleost fish - most likely Sparidae - or by sharks. However, other vertebrates, including toothed and toothless cetaceans and porpoises, cannot be ruled out. The terrestrial Miocene specimens include five morphotypes (hereinafter referred to as T-terrestrial, T1–T7): (T1) oval, (T2) sinusoidal, (T3) elongated with two submorphotypes (T3/1–siderite individuals and T3/2–apatite individuals), (T4) S-shaped, and (T5) irregular. They are interpreted as coprolites likely produced by snakes (T1–T3/1, T4, T5), and small mammals such as Sciuridae and/or Chiropteridae (T3/2). Overall, these data provide new insights into the diversity of post-Mesozoic coprolites and refine our understanding of their producers and associated ecosystems in Central Europe. creator: Tomasz Brachaniec creator: Dorota Środek creator: Mateusz Salamon creator: Michał Bugajski creator: Piotr Duda creator: Adam Danielak creator: Magdalena Janiszewska creator: Grzegorz Sadlok creator: Wojciech Kuśnierczyk uri: https://doi.org/10.7717/peerj.20242 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Brachaniec et al. title: Hidden microalgae diversity in reef systems: reanalysis of coral microbiomes reveals spatial patterns of coral-associated plastid communities in the Southwestern Atlantic Ocean (SWAO) link: https://peerj.com/articles/20116 last-modified: 2025-11-03 description: The microbial community associated with corals plays a critical role in reef ecosystems, yet studies mainly focus on prokaryotes and Symbiodiniaceae, overlooking other oxygen-evolving photosynthetic eukaryotes. This leaves a knowledge gap regarding potentially important microbiome members. Here, we revisited coral microbiome datasets to investigate the diversity of plastid-bearing eukaryotes associated with Southwestern Atlantic Ocean (SWAO) corals. We compiled an inventory of plastid-bearing communities, uncovering their diversity and exploring ecological patterns. We further applied this approach to analyze the plastidiomes (plastid-bearing communities) of corals from the Abrolhos Bank, the largest reef system in the region, as a case study. A systematic literature review of 16S rDNA-based coral microbiome was conducted, excluding studies lacking plastid 16S sequences. The search made in PubMed resulted in 19 studies reporting corals sampled from 2009 to 2022, which were compiled and reanalyzed. Sequences of chloroplast origin (Silva 132) were further taxonomically classified by consensus-BLASTn search with the PR2 plastid 16S database. The dataset encompassed reef water and coral microbiomes from eight coral species, emphasizing the genus Mussismilia. A total of 272 amplicon libraries yielded 707,949 plastid sequences, identifying 196 algal genera across 41 classes. Reef water and coral plastid communities differed markedly. Ostreobium (81%) and Calliarthron (49%) were the most prevalent genera in coral samples. Diatoms were common (>40% of samples) in the water and in corals, whereas corallicolids were exclusive to corals (31.8%). The Abrolhos case study revealed geographic variation in Mussismilia harttii plastidiomes, which were less diverse than those in the water column. Coral indicator taxa included Ostreobium, corallicolids, Navicula, and Amphora. Our findings identify plastidiome variations and their implications for the coral host. Lipid-rich diatoms prevalent in coral plastidiomes may support corals nutritionally after coral bleaching, while other free-living and bloom-forming microalgae produce significantly more reactive oxygen species than Symbiodiniaceae, potentially driving oxidative stress. These results highlight microeukaryotic community variation across corals and its ecological relevance, offering a framework for using plastid-bearing communities as biomarkers of shifts in coral holobionts. creator: Clara P. Pires creator: Livia B. Villela creator: Rodrigo L. Moura creator: Paulo S. Salomon creator: Arthur W. Silva-Lima uri: https://doi.org/10.7717/peerj.20116 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2025 Pires et al. title: Predation experiments with 3D-printed lizard models yield limited responses in pheasants link: https://peerj.com/articles/20103 last-modified: 2025-11-03 description: Animal colouration has been viewed as an adaptation shaped by both abiotic and biotic factors, balancing sexual attractiveness against predation risk. In studying predator-prey dynamics, using 3D models as prey surrogates is common, but material constraints can affect outcomes in both natural and seminatural settings. Here, we utilized 3D-printed models representing three colour morphs of sand lizards (Lacerta agilis) to investigate interactions with captive-bred pheasants (Phasianus colchicus) utilizing forced exploration experiments in an outdoor arena fitted with a grass carpet. The models adequately represented the lizard colouration across a reflectance spectral range of 330–800 nm. Our findings indicate that the pheasants generally exhibited a minimal response to static models, with significant differences observed only in younger birds (7–12 weeks old), demonstrating a higher alert response than adults. No effects were found relating to the colour morph or sex of the lizard models. These results suggest that immobile 3D-printed prey models may be insufficient to trigger natural predator responses in this predator-prey system, highlighting potential limitations of static models in eliciting predator reaction. creator: Radovan Smolinský creator: Ivo Adam creator: Zuzana Hiadlovská creator: Shubhra Sau creator: Pavel Škrabánek creator: Natália Martínková uri: https://doi.org/10.7717/peerj.20103 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Smolinský et al. title: Plant morphological traits and ecological stoichiometry in disturbed vs. conserved forests link: https://peerj.com/articles/20301 last-modified: 2025-10-31 description: Global forests are currently facing significant anthropogenic disturbances. Previous research on plant functional traits has predominantly focused on relatively intact forests, often overlooking those that have experienced such disturbances. This oversight has lead to a scarcity of relevant data regarding disturbed forests in the global and Chinese plant functional trait databases, thereby limiting our understanding of the life history strategies employed by plants inhabiting these altered environments. This study presents data on 12 morphological traits and 24 ecological stoichiometry traits for 62 common species in disturbed forests and 43 species in conserved forests in East China. We analyzed the variability characteristics of these functional traits, explored functional trait differences between disturbed and conserved forests, and examined relationships among various functional traits to investigate disparities in life history strategies between the two forest types. The results indicated that the variability of plant functional traits was generally lower in disturbed forests compared to conserved ones. Most functional traits exhibited significant differences between the two forest types (P < 0.05). Additionally, stronger correlations among functional traits were noted in disturbed forests. From a functional trait perspective, plants in disturbed forests displayed high trait correlations and formed trait combinations indicative of a resource conservative strategy characterized by low specific leaf area, high dry matter content and tissue density across leaves, twigs, barks and stems; alongside heightened carbon investment but reduced al locations for nitrogen and phosphorus. A comprehensive investigation of plant functional traits in both disturbed and conserved forests will enrich the global and Chinese trait databases, providing insights into how forest plants adapt to disturbances and informing ecological restoration in degraded areas. creator: Xiaoyin Guan creator: Haojun Xia creator: Shuming Li creator: Shuisheng Yu creator: Zihong Zheng creator: Julian Liu creator: Libin Liu uri: https://doi.org/10.7717/peerj.20301 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2025 Guan et al.