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PubMed2026

Clinical Utility of Ultra-Widefield Swept-Source OCT for Intraocular Tumors: Comparison With Ultrasonography, SD-OCT, and MRI.

PURPOSE: To evaluate the clinical performance of ultra-widefield swept-source optical coherence tomography (UWF-OCT) in the assessment of choroidal tumors and to compare it with ultrasonography (US), spectral-domain (SD)-OCT, and magnetic resonance imaging (MRI). DESIGN: Retrospective diagnostic comparison. SUBJECTS: Thirty-nine eyes from 39 patients diagnosed with choroidal tumors at a single tertiary referral center. METHODS: This retrospective diagnostic comparison evaluated patients diagnosed with choroidal tumors at a single tertiary referral center between January 2023 and August 2025. All patients underwent UWF-OCT imaging at diagnosis. Tumor measurements obtained with UWF-OCT were compared with US, SD-OCT, and MRI. Comparative analysis among imaging modalities and predictors affecting UWF-OCT applicability was performed. MAIN OUTCOME MEASURES: Tumor thickness (mm) and largest basal diameter (LBD, mm) measurements, and complete measurability rate across different tumor size categories. RESULTS: Thirty-nine eyes from 39 patients (mean age 59.2 ± 16.9 years) were analyzed, including 27 choroidal melanomas (69.2%), 5 metastatic tumors (12.8%), 4 hemangiomas (10.3%), 2 osteomas (5.1%), and 1 (2.6%) indeterminate choroidal melanocytic lesion. UWF-OCT successfully measured both tumor thickness and largest basal diameter (LBD) in 100% (31/31) of small and medium choroidal tumors, substantially outperforming SD-OCT (complete measurement achieved in 63.6% of small tumors, and 0% of medium or large tumors). UWF-OCT measurements were systematically smaller than ultrasonography (thickness: -32.3%, P < .01; LBD: -11.1%, P < .01) and MRI (thickness: -29.2%, P < .01). Mushroom-shaped tumor morphology was the strongest negative predictor of UWF-OCT quality (OR = 0.015, 95% CI 0.001-0.196, P < .01). UWF-OCT's complete measurability was limited in large tumors (12.5%, 1/8). CONCLUSIONS: UWF-OCT provides precise, noninvasive, single-scan assessment of small-to-medium choroidal tumors with detailed structural visualization. It may be particularly useful for dome-shaped tumors, while multimodal imaging with US and MRI remains optimal for complex morphologies. Overall, UWF-OCT represents a valuable tool for diagnosis and treatment planning, with potential utility for longitudinal follow-up in choroidal tumor management.

Humans↗

PubMed2026

Second-Generation ELZA-sub400 Protocol: Individualized High-Fluence Cross-Linking for Ultra-Thin Keratoconus Corneas.

PURPOSE: To evaluate the safety and efficacy of a second-generation individualized corneal cross-linking (CXL) protocol (ELZA-sub400) using high-fluence UV-A irradiation in ultrathin ectatic corneas. DESIGN: Retrospective, single-center, consecutive interventional case series. METHODS: Twenty-nine eyes of 24 patients with progressive keratoconus or post-LASIK ectasia and a post-soak intraoperative thinnest stromal thickness <400 µm were included. After epithelial removal and riboflavin soaking, continuous UV-A irradiation (365 nm) at 3 or 9 mW/cm² was delivered with total fluence titrated up to 10 J/cm² based on intraoperative ultrasound pachymetry and a previously published nomogram targeting an uncross-linked stromal margin of approximately 70 µm above the endothelium. Outcomes were assessed at baseline and up to 12 months using corrected distance visual acuity (CDVA) and corneal parameters measured using Scheimpflug tomography and anterior segment OCT (AS-OCT) with Placido-based topography. The main outcome measure was the proportion of eyes without progression at 12 months, defined as <1.0 D increase in maximum keratometry (Kmax). Secondary outcomes included changes in CDVA, refraction, Kmax, stromal thickness, demarcation line depth, densitometry, and safety parameters. RESULTS: At 12 months, 22/29 eyes (76%; 95% CI, 57.9%-87.8%) met the nonprogression criterion. Mean change in Kmax was -0.77 ± 5.10 D (95% CI, -2.71 to 1.17; P = .418). Mean demarcation line-to-anterior stroma distance was 205 ± 64 µm (95% CI, 180.7-229.3), and demarcation line-to-endothelium distance was 64 µm (IQR, 49-152). All demarcation lines remained within the stromal layer; 15/29 eyes (51.7%) had a demarcation line located ≤70 µm from the endothelium. Median CDVA changed from 0.10 to 0.32 logMAR (P = .142). Minimum stromal thickness showed a median change of -4.0 µm (P = .309). No significant change was observed in densitometry, and no eye developed deep stromal haze or endothelial decompensation. CONCLUSIONS: Second-generation ELZA-sub400 CXL halted ectasia progression in 76% of ultrathin corneas at 12 months and was associated with an acceptable short-term safety profile, including stromal-confined demarcation line formation and no observed endothelial decompensation. The numerical decline in spectacle CDVA observed in this severely affected cohort did not reach statistical significance but is clinically important and warrants confirmation in larger prospective studies.

Humans↗

PubMed2026

Safety of insulin eye drops in the treatment of open angle glaucoma: a randomized phase I clinical trial.

OBJECTIVE: The progression of glaucoma despite adequate intraocular pressure (IOP) control highlights the need for neuroprotective and neuroregenerative therapies. Preclinical studies suggest insulin promotes retinal ganglion cell survival and regeneration, but its safety in higher concentrations (100 and 500 units/mL), administered topically, has been poorly characterized in humans. We aim to assess the safety and tolerability of these two concentrations of insulin eye drops in patients with open-angle glaucoma (OAG). DESIGN: A phase I, randomized, double-blind, placebo-controlled, single-centre clinical trial. PARTICIPANTS: Patients with mild to moderate OAG were randomized 2:2:1 to receive once-daily topical insulin U-100, U-500, or placebo in 1 eye for 5 days, with follow-up visits at 1, 3, and 6 months. The primary safety outcomes include glycemia, serum potassium, ocular adverse events (AEs), and ocular tolerability scores. Secondary outcomes included IOP, best-corrected visual acuity (BCVA), retinal nerve fibre layer thickness, ganglion cell complex, visual field, and OCT angiography. RESULTS: Eighteen open-angle glaucoma patients were enrolled (mean age: 66.2 ± 10.1 years). No serious AEs related to insulin were observed. One asymptomatic, transient near-hypoglycemia event occurred in a fasting participant (3.9 mmol/L), with no recurrence after dietary adjustment. No significant changes were found in serum potassium, IOP, BCVA, visual fields, or OCT. Ocular symptoms in the insulin groups were limited to transient, mild burning sensation upon application. One participant experienced cystoid macular edema at 3 months, which was attributed to pre-existing ocular pathology. CONCLUSION: Topical insulin at 100 and 500 units/mL concentrations was well tolerated in patients for short-term use and did not result in significant systemic or ocular toxicity.

Aged↗

PubMed2026

Association of the Charlson Comorbidity Index With 1-Year Outcomes in Patients With Macular Edema Secondary to Retinal Vein Occlusion.

OBJECTIVE: To determine the predictive value of the Charlson Comorbidity Index (CCI) for outcomes in patients with macular edema secondary to retinal vein occlusion (RVO). DESIGN: Retrospective clinical cohort study. SUBJECTS: Patients seen between 2013 and 2023 at the Cole Eye Institute, Cleveland Clinic, were included. All patients were >18, diagnosed with RVO (International Classification of Diseases (ICD)-9 and 10 codes), had a complete CCI score, and had at least 1 year of ophthalmic follow-up data after their first intravitreal injection (baseline). Patients with ocular surgery, trauma, or panretinal photocoagulation were excluded. METHODS: Age-adjusted CCI scores were calculated for each patient from chart review. For patients with bilateral RVO, one eye was selected randomly. Patients were stratified into tertiles by CCI distribution: tertile 1 (CCI 0-5; mean 3.4), tertile 2 (age-CCI 4.1-6; mean 4.9), and tertile 3 (CCI ≥ 8; mean 9.6). Multivariable linear regression was performed to determine the predictive value of CCI and other covariates on visual and anatomical outcomes. MAIN OUTCOME MEASURES: Best-corrected visual acuity (BCVA) and central subfield thickness (CST) at 1-year follow-up. RESULTS: A total of 972 patients met all criteria, with an average age-adjusted CCI score of 6.2. Each one-point increase in CCI predicted 0.38 fewer letters in BCVA at follow-up (P < .001). Baseline BCVA was a significant predictor of follow-up BCVA in all tertiles (P < .001). In the third tertile, each one-point increase in CCI was associated with a 0.72 letter reduction in follow-up BCVA (P < .001). For CST, baseline CST was strongly predictive of final CST (P < .001), while CCI was only significant in the first tertile, where each point increase in CCI predicted a 13.7 µm increase in CST (P = .02). In RVO subtype interaction models, the age-adjusted CCI × CRVO interaction was not statistically significant for either 1-year BCVA (P = .269) or 1-year CST (P = .695). CONCLUSIONS: Higher CCI scores are significantly associated with worse visual outcomes in patients with RVO, particularly in the combined population and most comorbid patients (tertile 3). CCI was significantly associated with higher (thicker) CST only among the least comorbid patients (tertile 1).

Humans↗

PubMed2026

Development of the zebrafish foveal analogue: a quantitative atlas of high-acuity zone growth and retinal regionalisation.

The vertebrate retina contains specialised regions for high-acuity vision, exemplified by the human fovea and its zebrafish analogue, the high-acuity zone (HAZ). Despite the widespread use of zebrafish to model retinal disease, a stage-resolved quantitative reference describing normal eye, photoreceptor layer (PRL) and lens growth has been lacking. Here, we apply contrast-enhanced micro-computed tomography (micro-CT) to construct the first three-dimensional micro-CT normative atlas of wild-type zebrafish eye development across five larval stages [3, 5, 7, 10 and 18 days post-fertilisation (dpf)], mapping circumferential PRL thickness, eye and lens morphology, and compartment growth rates. Regional PRL thickening within the temporo-ventral region of the expected HAZ emerged by 5 dpf and was sustained by a localised redistribution of growth, persisting and extending towards the optic nerve through 18 dpf. The PRL, lens and eye grew through four phases, alternating between disproportionate PRL expansion and coordinated growth, while the eye remodelled from a nasal-dominant to a temporo-ventral-dominant form. This regional specialisation was protracted relative to gross ocular growth and could proceed independently of it, paralleling the extended postnatal maturation of the human fovea. This atlas provides a quantitative baseline for distinguishing disease-induced changes from normal variation, supporting zebrafish models of foveal hypoplasia and related disorders.

Animals↗

PubMed2026

Late hiatal hernia after Roux-en-Y gastric bypass: a systematic review.

Obesity is a global public health issue. This condition is linked to gastroesophageal reflux disease (GERD) and hiatal hernia (HH), both of which are exacerbated by increased intra-abdominal pressure. Roux-en-Y gastric bypass (RYGB) is one of the most widely performed techniques for treating obesity and is considered a versatile option suitable for most patients. The development of a symptomatic HH and pouch migration can lead to various symptoms and complications. PubMed, EMBASE, and Cochrane Central were searched for studies with late HH after RYGB. We pooled outcomes for symptom resolution. Secondary outcomes were recurrence rate and operation characteristics (mesh use, cruroplasty, gastropexy, reoperation, length of stay, and operative time). A meta-analysis could not be conducted due to significant heterogeneity in HH. HH following RYGB presents with GERD (39-93.6%), obstructive symptoms (29%-88%), and abdominal pain (28.6%-71%). Diagnostic methods include endoscopy, computed tomography scans, and upper gastrointestinal series. Surgical management varies, with primary cruroplasty being the most common approach, sometimes incorporating mesh or fundoplication. Postoperative symptom resolution rates range from 42.9% to 100%, with HH recurrence occurring in 5%-6.54% of cases. Follow-up durations varied, showing improvement in most patients, though some continued to experience reflux and dysphagia HH contributes to obstructive and reflux symptoms, with contrast-enhanced imaging offering the highest diagnostic accuracy. Bioabsorbable mesh may reduce recurrence, highlighting the need for long-term monitoring.

Humans↗

PubMed2026

Radiographic assessment and orthodontic intervention effects on orthodontically induced root resorption: a systematic review and meta-analysis of clinical trials.

The relative contribution of radiographic methods and characteristics of the orthodontic intervention to orthodontically induced root resorption (OIRR) remains unknown. The aims of this systematic review and meta-analysis were to (1) estimate the pooled OIRR effect across orthodontic intervention versus comparator contrasts, (2) compare pooled estimates by radiographic method (2D [two-dimensional] vs. 3D/CBCT [three-dimensional/cone-beam computed tomography]), and (3) explore whether force mechanics (intrusive versus nonintrusive) modified OIRR magnitude. Seven randomized controlled trials and one prospective study (January 2010-October 2025) were included. Only OIRR was the outcome, reported as correlation coefficients (r). The primary analysis combined within-study intervention-versus-comparator estimates. Subgroup analysis of 2D versus 3D/CBCT imaging was prespecified, whereas post-hoc analysis of intrusive versus nonintrusive mechanics was performed. The pooled analysis for the primary outcome showed a small, nonsignificant OIRR effect (r = 0.07; 95% confidence interval [CI]: -0.12 to 0.27; p = 0.372) with high heterogeneity (I2 = 84.0%). Radiographic method did not change the pooled estimates significantly (p = 0.331). Force-mechanics analysis showed that intrusive mechanics was related to significantly higher root resorption than nonintrusive mechanics (r = 0.40; 95% CI = 0.15 to 0.65 versus r = -0.03; 95% CI = -0.16 to 0.10; p < 0.001). This accounted for 87.1% of the between-study variance. The average orthodontic intervention effect on OIRR was small and not significant; however, the OIRR magnitude was strongly affected by force mechanics, particularly by intrusive forces. There was no significant difference in pooled estimates by radiographic method; however, 3D/CBCT provides superior volumetric quantification and should be used judiciously according ALARA (as low as reasonably achievable) principles.

Root Resorption↗

PubMed2026

Effect of Baseline ASPECTS on Tenecteplase Efficacy Before Thrombectomy in Acute Large-Vessel Occlusion Stroke: A Post Hoc Analysis of the BRIDGE-TNK Randomized Trial.

BACKGROUND AND OBJECTIVES: The impact of ischemic extent on the efficacy and safety of intravenous thrombolysis before thrombectomy remains uncertain. The aim of this study was to evaluate whether the baseline ischemic extent, measured by the Alberta Stroke Program Early Computed Tomography Score (ASPECTS), modifies outcomes of intravenous tenecteplase administered before endovascular thrombectomy. METHODS: This was a post hoc analysis of the BRIDGE-TNK (thrombectomy with vs without rhTNK-tPA in stroke) trial, conducted across China from May 2022 to September 2024. We compared the efficacy and safety of intravenous tenecteplase plus thrombectomy vs thrombectomy alone in acute large-vessel occlusion stroke patients within 4.5 hours of last known well, stratified by baseline ASPECTS (<8 vs 8-10). The outcomes included 90-day functional independence (modified Rankin Scale score of 0-2), 48-hour symptomatic intracranial hemorrhage (sICH), and 90-day mortality. Regression models incorporating a treatment-by-ASPECTS interaction term were used for analysis. RESULTS: Among 550 patients, 241 (43.8%) had ASPECTS <8 (median [interquartile range, IQR] age, 69 [61-77] years; 56.4% male) and 309 had ASPECTS 8-10 (median [IQR] age, 70 [61-77] years; 59.5% male). The rate of functional independence was significantly higher in the tenecteplase plus thrombectomy group than in the thrombectomy-alone group in the ASPECTS <8 subgroup (adjusted risk ratio [aRR], 1.67; 95% CI 1.18-2.35), but not in the ASPECTS 8-10 subgroup (aRR, 0.99; 95% CI 0.84-1.17; pinteraction = 0.007). Rates of sICH did not differ significantly between treatment groups in either ASPECTS subgroups (ASPECTS <8: 10.0% vs 11.2%; ASPECTS 8-10: 7.5% vs 2.8%; pinteraction = 0.11). Ninety-day mortality was comparable between treatment groups in the ASPECTS <8 subgroup, but numerically higher with tenecteplase plus thrombectomy in the ASPECTS 8-10 subgroup (aRR = 1.89, 95% CI 0.99-3.61, pinteraction = 0.04). DISCUSSION: In this exploratory post hoc analysis, a signal of benefit was observed in patients with ASPECTS <8 who received intravenous tenecteplase before thrombectomy, whereas no functional improvement and possible safety concerns were seen in those with ASPECTS 8-10. Prospective confirmation in randomized trials is required before practice change. TRIAL REGISTRATION INFORMATION: ClinicalTrials.gov; Unique identifier: NCT04733742.

Humans↗

PubMed2026

Desmodium styracifolium Total Flavone Capsules for Urolithiasis: A Phase 3 Randomized Clinical Trial.

IMPORTANCE: No oral medication is currently approved for the management of urolithiasis. Guang Jing Qian Cao (Desmodium styracifolium total flavone capsules; hereinafter, Guang Jing), a traditional Chinese herbal extract, has shown clinical benefits for urolithiasis, but randomized clinical trials are needed to assess its effectiveness. OBJECTIVE: To evaluate whether Guang Jing improves stone passage rates (SPRs) compared with placebo in adults with urolithiasis. DESIGN, SETTING, AND PARTICIPANTS: This double-blind, placebo-controlled, phase 3 randomized clinical trial was conducted at 34 sites in China from December 2017 to April 2020. Participants included adults (aged 18-70 years) with diagnosed ureteral stones. Data analysis was conducted on November 4, 2020. INTERVENTION: Participants were randomized 3:1 to receive oral Guang Jing (0.6 g) or matching placebo 3 times daily for 28 days, in addition to investigator-prescribed background medication. MAIN OUTCOMES AND MEASURES: The primary outcome was SPR by day 28, confirmed by computed tomography. Secondary outcomes included SPR by day 14, stone migration rate, and stone migration distance. Between-group comparisons were performed using the Cochran-Mantel-Haenszel test for categorical outcomes and t tests for continuous outcomes. RESULTS: A total of 606 participants were randomly assigned to receive Guang Jing (n = 458) or placebo (n = 148). Their mean (SD) age was 43.0 (12.0) years, 474 (78.2%) were male, and the mean (SD) stone size was 0.6 (0.1) cm. The SPR by day 28 was significantly higher for the Guang Jing group compared with the placebo group (204 of 457 [44.6%] vs 50 of 148 [33.8%]; relative risk, 1.32 [95% CI, 1.03-1.69]; P = .03), with an absolute risk difference of 10.9 (95% CI, 2.0-19.7) percentage points. No significant between-group differences in SPR by day 14 (Guang Jing vs placebo: 133 [29.1%] vs 33 [22.3%]; P = .14) or stone migration distance (mean [SD], 29.5 [51.8] mm vs 29.7 [43.8] mm; P = .11) were observed. Adverse event rates were similar for the Guang Jing and placebo groups (88 [19.3%] vs 27 [18.2%]). CONCLUSIONS AND RELEVANCE: In this randomized clinical trial, treatment with Guang Jing significantly increased the expulsion of 5- to 10-mm ureteral stones by day 28, with a favorable safety profile. These findings suggest that Guang Jing may be an additional medical expulsive therapy option for appropriately selected patients. TRIAL REGISTRATION: Chinese Clinical Trial Registry Identifier: ChiCTR-IIR-17013275.

Humans↗

PubMed2026

Stable chloroform emissions in southeastern China: insights from recent observations.

Chloroform (CHCl3) is a short-lived ozone-depleting substance not currently regulated under the Montreal Protocol. Due to the unique meteorological conditions in East Asia, CHCl3 emitted in this region has a greater potential to reach the stratosphere and contribute to ozone depletion. As an essential component of national CHCl3 emissions, southeastern China has attracted increasing attention. However, long-term observational data in this region remain relatively scarce, with no updates since 2020. In this study, we continuously measured atmospheric CHCl3 concentrations at a remote monitoring station in southeastern China from 1 June 2023 to 31 May 2025. Frequent concentration enhancements were observed during the monitoring period, with mixing ratios ranging from 9.3 to 134.1 ppt and an average value of 36.8 ± 19.7 ppt. Back-trajectory analysis indicated that air masses associated with elevated CHCl3 levels primarily originated from coastal industrial provinces in eastern China. Using the Potential Source Contribution Function and Concentration Weighted Trajectory methods, we identified the Yangtze River Delta (Jiangsu, Anhui, and Zhejiang Provinces) and Jiangxi Province as dominant source regions. Emissions of CHCl3 in southeastern China were estimated using the Tracer Ratio Method to be approximately 30.1 ± 5.3 Gg/yr from 2023-06-01 to 2025-05-31, indicating overall stability relative to earlier estimates and no apparent upward trend. These findings provide updated insights into the current status of CHCl3 emissions in southeastern China and highlight the need for continued monitoring and emission assessment of CHCl3 in East Asia, given its unregulated status and implications for ozone layer recovery.

Air Pollutants↗

PubMed2026

Hip Arthroscopy-Assisted Management of Pipkin Types I and II Femoral Head Fracture-Dislocations: Mid-Term Clinical and Radiographic Outcomes.

OBJECTIVES: Hip arthroscopy-assisted surgery has been proposed as a minimally invasive option for femoral head fractures; however, evidence with mid-term follow-up remains limited. This study aimed to evaluate the clinical and radiographic outcomes of arthroscopy-assisted management for Pipkin Types I and II femoral head fracture-dislocations with a minimum follow-up of 5 years. METHODS: This retrospective study included 23 consecutive adults (19 Pipkin I and 4 Pipkin II) treated with hip arthroscopy-assisted fragment excision or internal fixation between March 2013 and January 2020. Preoperative computed tomography was used for surgical planning, and fixation was placed with arthroscopic headless screws. Clinical outcomes were assessed using the Harris Hip Score (HHS) and Thompson-Epstein (T-E) criteria. Radiographic evaluation included avascular necrosis (AVN), heterotopic ossification (HO; Brooker), osteoarthritis (OA; Tönnis), and fracture reduction quality (Matta's criteria). Group comparisons were evaluated using independent samples t-tests, Mann-Whitney U tests, and Fisher's exact test. The mean follow-up was 86.2 ± 21.2 months. RESULTS: The cohort consisted of 19 males and 4 females with a mean age of 28.7 ± 9.9 years. Fifteen patients underwent fixation and eight underwent excision. The final mean HHS was 98.3 ± 1.9, with 21 patients (91%) achieving excellent and 2 (9%) good T-E criteria. There were no significant differences between the fixation and excision groups in demographic characteristics, operative time, or functional outcomes (all p > 0.05); however, hospital stay was significantly shorter in the excision group (2.9 ± 0.6 vs. 5.5 ± 4.6 days, p = 0.028). In the fixation group, mean maximal displacement improved from 7.6 mm preoperatively to 2.6 mm postoperatively, with anatomic reduction achieved in 6 cases (40%), imperfect in 6 (40%), and poor in 3 (20%). Patients with Pipkin Type I fractures had significantly higher HHS than those with Type II fractures (98.7 ± 1.7 vs. 96.0 ± 0.8, p = 0.018). Complications were rare, with one case of Brooker Grade I HO and one case of mild OA. No AVN or total hip arthroplasty occurred during the follow-up. CONCLUSIONS: Hip arthroscopy-assisted management of selected Pipkin Type I and II femoral head fractures yields excellent mid-term clinical outcomes with acceptable radiographic reduction and a low complication rate. This minimally invasive technique represents a viable alternative in appropriately selected patients when fragment characteristics and surgical expertise permit.

Humans↗

PubMed2026

Littoral and wetland vegetation decrease carbon emissions from dry inland waters.

Lakes are recognized as active components of the inland water carbon (C) cycle, as organic matter is processed by microbial respiration, inducing large carbon dioxide (CO2) and methane (CH4) emissions. In the context of long-lasting drought periods, large uncertainties remain about: (1) the influence of wet-dry cycle on CO2 and CH4 fluxes in littoral zones and lacustrine wetlands; and (2) the contribution of emergent vegetation to C fluxes in dry inland waters. At the water-land interface of two shallow lakes, this study focuses on CO2 and CH4 fluxes from vegetated and bare dry inland waters in relation to hydrological fluctuations. Three seasonal campaigns were conducted to measure daytime CO2 and CH4 fluxes in pelagic, littoral and wetland surface waters, as well as in temporarily air-exposed sediments, using floating and static chambers, respectively. Our results reveal that wet-dry cycle in the littoral zone and wetlands strongly influence gaseous C fluxes through contrasting patterns, especially in late summer, when the biological processes are most active (primary production and respiration). In air-exposed littoral zones, organic-poor sandy sediments presented the lowest CO2 and CH4 emissions, whereas in air-exposed lacustrine wetlands, water-saturated sediments accumulated high amounts of plant-derived organic matter, promoting intense microbial activity and the highest C emissions. However, amphiphytes and helophytes vegetation in exposed littoral zones and wetlands reversed the direction of C fluxes, inducing the highest CO2 uptake due to high photosynthesis rates. This study underlines the relevance of considering vegetation in dry inland waters, particularly in lacustrine littoral zones and wetlands, to obtain comprehensive lake C budgets, especially under climate change scenarios.

Wetlands↗

PubMed2025

An integrated multiscale air quality modelling framework for industrial park pollution: Linking local emissions to regional transport.

Capturing the spatiotemporal distribution of pollutants in industrial parks remains challenging for regional air quality models because of their coarse resolution (3 km), resulting in uncertainties in local emission quantification. To address this, we developed the Integrated Multiscale Air Quality Modelling System for Industry (IAQMS-Industry), coupling the regional Nested Air Quality Prediction Modelling System (NAQPMS) with a city-scale chemical transport model. This framework integrates point-source locations and Gaussian plume dispersion to simulate particulate matter with a diameter smaller than 2.5 micrometres (PM2.5) at 100 m resolution. Applied to the Beijing Yi Zhuang and Tangshan industrial parks and evaluated against observations. The coupled model achieved a normalized mean bias (NMB) ranging from 3.1 % to 6.2 %, improving upon NAQPMS (-16.9 % to -7.7 %). Spatial analysis revealed that coarse regional grids underestimated the PM2.5 concentrations at industrial sites by smoothing gradients, whereas IAQMS-Industry successfully resolved spatial patterns. Industrial point emissions accounted for 22.9 %-26.4 % of PM2.5 in the coupled model, which was significantly greater than the regional model estimates of 1.6 %-13.7 %. These findings indicate that regional models overestimate pollutant dispersion processes in industrial parks while underestimating local industrial impacts. By explicitly resolving point-source dynamics and linking them to regional transport, IAQMS-Industry provides a robust tool for designing targeted emission controls in industrial cities and balancing local air quality improvements with minimized regional pollution outflow. This study underscores the necessity of multiscale modelling for accurate source apportionment and informed environmental governance in industrial zones.

Air Pollution↗

PubMed2026

Impacts of climate-driven yield changes on the affordability of healthy diets: a modelling study.

BACKGROUND: Food security is central to global nutrition improvement and public health goals, and healthy diets represent a higher-level aspiration beyond merely avoiding hunger. Climate change poses an increasing threat to food systems by affecting crop yields and food prices. Although climate change-driven risks to hunger have been widely studied, the extent to which climate change undermines the affordability of healthy diets while accounting for socioeconomic responses and regional inequalities remains insufficiently understood. This study aimed to quantify the effects of climate change on the future affordability of healthy diets under alternative socioeconomic and climate scenarios. METHODS: We developed an integrated modelling framework that explicitly couples multimodel crop-yield projections with an integrated assessment model (Global Change Analysis Model [GCAM]). Yield responses from six global gridded crop models driven by four climate models were integrated into GCAM, allowing endogenous socioeconomic adjustments such as land-use shifts, production reallocation, and price responses to emerge under shared socioeconomic pathways (SSPs). Diet affordability was then assessed using the Food and Agriculture Organization of the UN's Cost and Affordability of a Healthy Diet framework across three socioeconomic-climate scenarios (SSP1-2.6, SSP2-4.5, and SSP3-6.0). FINDINGS: Under a high-emissions pathway (ie, SSP3-6.0), climate change was projected to render healthy diets unaffordable for a model-mean of 119 million people globally by 2100, even when CO2 fertilisation effects are included, with the upper end of the model ensemble reaching about 1·6 billion people. In contrast, climate-induced affordability losses were found to be negligible under both a low-emissions pathway (ie, SSP1-2.6; -0·3 million) and a medium-emission pathway (SSP2-4.5; +0·2 million). Under a high-emission pathway, model-mean projections indicated that diet costs could increase by up to 12% in the most affected regions by the end of the century. Under medium emissions, cost increases were projected to remain below 4%, whereas under low emissions, affordability changes were projected to be minimum across regions (within approximately 0·5%). Substantial regional disparities emerged, with the largest and most consistent affordability losses concentrated in low-income regions that contributed least to historical greenhouse gas emissions. Under SSP3-6.0, these disparities persisted particularly in regions of Africa and Asia despite projected three-to-five-fold increases in income over the century, with climate-induced disruptions to food systems increasing the number of people unable to afford a healthy diet through mid-century. INTERPRETATION: Climate change is likely to exacerbate global nutritional inequalities by disproportionately increasing the affordability risks of healthy diets in regions that have contributed least to historical greenhouse gas emissions. Under high-warming scenarios, socioeconomic development alone is insufficient to fully offset these risks, highlighting the structural vulnerability of low-income food systems to climate-driven price shocks. These findings suggest that in the absence of targeted interventions, climate change could continue to undermine progress towards equitable and health-oriented nutrition outcomes. FUNDING: Ministry of Science and Technology of the People's Republic of China; National Natural Science Foundation of China; National Aeronautics and Space Administration Goddard Institute for Space Studies Climate Impacts Group; Future of Life Institute; and Global Alliance for Improved Nutrition.

Journal Article↗

PubMed2026

Biomass burning contributions to Mexico City's atmospheric CO2 estimated using a multi-isotope approach.

Fossil fuel combustion dominates anthropogenic emissions worldwide; however, special attention should be addressed to biomass burning, since it is an increasingly important contributor under warmer, drier fire-weather conditions exacerbated by climate change. These emissions could impact the atmospheric composition of heavily urbanized environments. To assess the influence of biomass burning, along with fossil fuels combustion and soil and plant respiration on Mexico City's atmospheric composition, we conducted a year-long (December 2023-December 2024) isotopic monitoring of atmospheric CO2, combining radiocarbon (Δ14C), CO2 stable isotopes (δ13C, δ18O), and CO/CO2 ratios. Once defined the isotopic signatures and the characteristic CO/CO2 that describe the sources, we performed Monte Carlo simulations under two tracer modalities (Δ14C + CO/CO2 and Δ14C + CO2 stable isotopes) for source apportionment. Results show that during the dry season, particularly in March-April, atmospheric Δ14C values approached and overlapped background levels despite Mexico City's fossil-fuel dominance, indicating enhanced non-fossil inputs. Moreover, backward HYSPLIT trajectories supported that these elevated Δ14C values coincided with regional wildfire activity. Monte Carlo results attributed up to ∼34 %-60 % of local CO2 to biomass burning in April, followed by March with contributions of ∼31 %-49 %. Since these biomass burning figures contrast with the official emissions inventory of Mexico City metropolitan area, which assigns <1 % of total CO2 emissions to biomass burning, this study could exhibit the emissions inventory underestimation of this source, and thus, the need to reassess and incorporate top-down isotopic constraints in fire-affected urban regions.

Mexico↗

PubMed2025

Coupling of spectroscopy and nitrogen-oxygen isotopes unveils the mechanisms of dissolved organic matter and nitrate pollution in lakes within the agro-pastoral transition zone.

Lakes in arid and semi-arid regions are subjected to severe ecological stress, such as organic pollution, eutrophication, and salinization, due to climate change and human activities. This study investigates Chagannur Lake, a typical arid-region lake that is representative and ecologically sensitive in Northern China's agro-pastoral ecotone, to uncover its pollution characteristics and mechanisms. We employed fluorescence spectroscopy and stable isotope analysis to trace dissolved organic matter (DOM) and nitrate sources. The DOM composition was dominated by microbial metabolic byproducts and protein-like substances, suggesting that microbial processes are key to organic matter transformation. Source apportionment revealed that pollutants primarily originated from livestock and poultry manure (37.6 %), agricultural fertilizers (35.6 %), and soil erosion (24.7 %), with agricultural fertilizers contributing most significantly in the Gogstai River (63.3 %). A structural equation model (SEM) coupling spectral and mass spectrometric data revealed that microbial transformation significantly impairs the lake's self-purification capacity, thereby promoting pollutant accumulation (path coefficient = 0.91,*p < 0.05). Moreover, microbial processes link endogenous and exogenous pollution, a mechanism effectively traced by isotopic and fluorescence indices (path coefficient = 0.55, ⁎⁎p < 0.01). These findings enhance the understanding of pollution sources and transformation mechanisms in arid-region lakes and offer foundational theoretical support for policymakers engaged in pollution control strategies.

Lakes↗

PubMed2026

Three-dimensional source apportionment and quantitative characterization of horizontal and vertical transport fluxes of O3 and its precursors in the Beijing-Tianjin-Hebei region, China.

Persistent surface ozone (O3) pollution in the Beijing-Tianjin-Hebei (BTH) region is driven by coupled precursor emissions and multi-scale transport, yet its altitude-dependent transport and source contributions remain insufficiently quantified. Here we integrated the Weather Research and Forecasting and the Comprehensive Air Quality Model with Extensions with the Ozone Source Apportionment Technology and a quantitative transport-flux framework to characterize three-dimensional source apportionment and horizontal/vertical fluxes of O3, Volatile Organic Compounds‌ (VOCs), and Nitrogen Oxides (NOx) across dynamic meteorological scenarios. Simulations showed that VOCs and NOx were dominated by local emissions near the surface (73.61 %-82.18 %), whereas surface O3 was primarily controlled by regional transport, with local contributions of only 11.01 %-13.75 %. Notably, the transport dominance further strengthened with altitude, exceeding 93 % at 1.8 km. Industrial and transportation emissions together contributed more than 75 % of precursor emissions and account for approximately 80 % of O3 formation, while favorable/unfavorable meteorological years modulated long-range transport efficiency and the vertical distribution of contributions. Horizontal flux analysis highlighted three major pathways (Northwest-Southeast, Southeast-Northwest, and Southwest-Northeast), with Shijiazhuang serving as a critical pollutant "sink" across altitude layers. Vertical fluxes revealed an altitude transition near 600 m: net downward transport dominated below 600 m, whereas enhanced summer convection promoted upward transport above 600 m. These results support altitude-dependent, scenario-specific strategies for coordinated regional O3 mitigation in the BTH region.

Ozone↗

PubMed2026

Modelling peak microbial pollution events caused by combined sewer overflows in a source-to-sea system.

Predicting peak microbial pollution events in downstream coastal bathing waters caused by combined sewer overflows (CSOs) is essential for protecting public health. In urban areas, wastewater effluents, CSOs, and surface runoff can contribute to elevated microorganism loads to downstream waters. These pressures are likely to be intensified by growing population density and more frequent heavy rainfalls due to climate change. This study developed a process-based model to simulate Escherichia coli (E. coli) emissions, transport, and fate from the initial sources to coastal beaches. A three-year retrospective simulation (2017-2019) shows that E. coli concentrations in CSO discharges varied widely across the catchment (4.6 - 7.3 (log10 CFU 100 ml-1)). 99th percentile E. coli concentrations (4.0 (log10 CFU 100 ml-1)) at the inland water outlet were dominated by local CSO emissions, whereas 90th percentile E. coli concentrations (3.6 (log10 CFU 100 ml-1)) reflected cumulative upstream contributions from both CSO and effluent emissions. With the simulation accuracy of 89%, the model reliably reproduced the E. coli dynamics on the downstream beach and showed strong performance in representing peak concentrations based on Complementary Cumulative Distribution Function (CCDF) analysis. The process-based model enables quantitative tracking of source contributions and identification of pollution hotspots, providing support for mitigation measures. The study lays down a source-to-sea modelling framework for representing pollution transport across the aquatic continuum and provides a transferable tool for microbial pollution forecasting and climate adaptation planning.

Climate projection↗