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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

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

Meta-analysis of source identification and apportionment in soil: A systematic review of analytical procedures, receptor modeling, and environmental applications.

Soil pollution poses significant risks to ecosystems and human health, necessitating accurate source identification and apportionment to guide mitigation strategies. This systematic review evaluates the application of Positive Matrix Factorization (PMF) and other receptor models in soil pollution studies, focusing on analytical procedures, tracer indicators, and environmental applications. This review aims to provide a comprehensive framework for conducting soil source apportionment studies, aiding policymakers in designing effective, region-specific environmental management strategies by compiling global trends and methodological insights. The study addresses sampling protocols, emphasizing representativeness and quality control. Data from 500 peer-reviewed publications highlight the dominance of research in China, Eastern Europe, and South Asia, with agricultural soils being the most frequently studied. Key findings reveal that traffic emissions (20.8 %) and industrial activities (19.4 %) are the primary global contributors to soil contamination, with regional variations such as coal combustion in cold climates and agricultural inputs in developing regions. Policy recommendations include stricter industrial regulations, sustainable agricultural practices, and targeted remediation efforts based on source-specific risks.

Soil Pollutants

Non-parametric differential methylation analysis characterizes histotype-specific promoter regions in epithelial ovarian cancer.

Epithelial ovarian cancer (EOC) is a heterogenous disease with frequent late-stage diagnosis and high mortality rates, for which no reliable screening tests exist. In recent years, epigenetic biomarkers in the form of DNA methylation in CpG-rich regions have gained increased attention in the scientific community due to their robust nature and accessibility, allowing for diagnosis without the need for invasive surgery. In this study, we investigated the aberrant methylation of promoter regions in early stage EOC through non-parametric methods, with the purpose of characterizing candidate epigenetic biomarkers. The approach was used on a cohort of early stage EOC samples, and results were compared to existing programs for differential methylation. Significant regions were then used to construct a CpG panel for stratifying EOC histotypes through predictive classification in external data. Identified promoter regions were highly reproducible across cohorts, and the constructed CpG model stratified histotypes in external cohorts through predictive classification. Comparisons against other DMP and DMR callers showed a degree of homogeneity between results but also revealed promoter regions that were overlooked despite clear signs of aberrant methylation. Finally, EOC histotypes were found to differ in their methylation distribution types, and results indicate that methods sensitive to non-normally distributed data may be poorly suited to compare groups with different distribution types. The non-parametric approach identified aberrantly methylated promoter regions that were highly reproducible across cohorts. Results from predictive classification indicate that these regions may be useful for the purpose of EOC histotype stratification.

Humans

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, &#x204e;&#x204e;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

Liver Cancer Risk and Incidence Attributable to Human Immunodeficiency Virus: A Meta-Analysis and Population-Attributable Modeling Study of Over 1.2 Million Individuals.

HIV-induced immune suppression and chronic inflammation elevate the risk of cancer progression. We conducted a systematic review and meta-analysis of studies published between January 1, 1984 and October 13, 2023 to assess the association between HIV infection and liver cancer. People living with HIV (PLHIV) had a higher risk (pooled relative risk&#x2009;=&#x2009;3.36, 95% CI: 2.72-4.15). The global PAF for HIV-attributed liver cancer was 1.43% in 2019, with a three-fold increase over the past 30&#x2009;years. The Asia-Pacific region recorded the second highest new cases of HIV-attributed liver cancer in 2019, and the highest age-standardized incidence rate (ASIR) in Eastern and Southern Africa. Particularly, the ASIR of HIV-attributed liver cancer increased rapidly in Eastern Europe and Central Asia, with the highest estimated annual percentage change reaching 22.98%. PLHIV have an increased risk and incidence of liver cancer. In regions with high burden of HIV-attributed liver cancer, it is essential to integrate prevention and effective treatment for HIV, viral hepatitis, alcoholic liver disease, nonalcoholic steatohepatitis, and liver cancer.

Humans

Unraveling the c-Myc-CASC19/HDAC1-NPM1 epigenetic axis: A novel regulatory circuitry and therapeutic target in gastric carcinogenesis.

Mounting evidence implicates long non-coding RNA cancer susceptibility candidate 19 (CASC19) in the pathogenesis of diverse malignancies. However, its functional role and molecular mechanisms in gastric cancer (GC) remain elusive. Herein, we identified a novel 717-bp transcript isoform of CASC19 in GC cells. This study aimed to delineate the biological functions and underlying mechanisms of this novel CASC19 transcript in GC pathogenesis. CASC19 was significantly upregulated in GC tissues and cell lines, correlating with adverse clinicopathological features and poor prognosis in GC patients. Functional investigations demonstrated that CASC19 overexpression potentiated GC cell proliferation, metastasis, and epithelial-mesenchymal transition, whereas CASC19 knockdown attenuated these malignant phenotypes and suppressed tumorigenesis in xenograft models. Mechanistically, CASC19 functioned as a molecular scaffold by recruiting histone deacetylase 1 (HDAC1) to the nucleophosmin 1 (NPM1) promoter. This recruitment sustained H3K27 deacetylation, thereby transcriptionally repressing NPM1 promoter activity and accelerating gastric carcinogenesis. Crucially, Depletion of HDAC1 or NPM1 partial rescued CASC19-mediated oncogenic effects. Intriguingly, the transcription factor c-Myc was found to transcriptionally activate CASC19 through direct binding to its promoter region. Collectively, our findings indicate that the c-Myc-CASC19/HDAC1-NPM1 axis acts as a potential prognostic biomarker candidate for GC and may represent a therapeutic vulnerability worthy of future investigation.

Humans

A systematic review of macaque brain stimulation: Trends and future directions.

Neurostimulation techniques can powerfully modulate neural circuit activity and provide causal insights into the relationship between brain function and behavior. Macaque monkeys have long been a key animal model for brain stimulation studies. While stimulating the macaque brain with one or a few electrodes has already taught us much about brain function and dysfunction, recent technological advances promise a future with more precise stimulation using many more electrodes. However, such possibilities also increase the number of choices an experimenter has when designing their study. We can learn from a rich past, but a comprehensive overview of which brain regions have been studied and with what stimulation parameters is lacking. Here, we present a PRISMA-compliant systematic review of 734 macaque brain stimulation studies using electrical and/or optogenetic stimulation. We find a striking bias in which brain areas have traditionally been stimulated: a mere 10 brain regions account for half of all studies, with the remainder of studies investigating approximately 150 other areas. Across studies, stimulation frequency robustly predicted direct behavioral effects independent of brain region, while amplitude did not. Future studies could more systematically explore less studied regions through lower stimulation frequencies (e.g., 20-50&#x202f;Hz) alongside established ranges (&#x223c;200&#x202f;Hz). Tools such as fMRI or optical imaging can capture neural circuit engagement evoked by these frequencies, even when behavioral effects are absent or remain subtle. Our synthesis offers a guide towards the next steps in high-channel-count, high-precision stimulation approaches.

Animals

Frequency of Human Brucellosis Complications in West Asia: A Systematic Review and Meta-Analysis.

BACKGROUND: Brucellosis is a multi-systemic zoonotic infection. The West Asia/Middle East region is an important global hotspot for brucellosis. This systematic review and meta-analysis aimed to aggregate and synthesize all the available evidence regarding the complications of brucellosis in West Asia/Middle East region. METHODS: PubMed, Embase, Scopus, Web of Science, Google Scholar, and Proquest were searched. Selection of studies, data extraction, and the risk of bias assessment were performed in duplicate. Data extraction was performed for 254 complications. Meta-analysis was performed using a random-effects model with Freeman-Tukey double arcsine transformation. Where applicable small-study effects was assessed using funnel plots and Egger's test. Separate by-country, by-age, and by-publication-decade subgroup analyses were performed if feasible. RESULTS: Out of 9518 results, 240 studies (260 references) were included. The majority of the included studies were conducted in Turkey (n&#x2009;=&#x2009;177). The reported complications varied and different complication categorization systems were detected. The highest pooled estimate was observed for musculoskeletal involvement (50%, 95%CI: 39%-61%, I2&#x2009;=&#x2009;96.63%). The evidences is up-to-date until March 4, 2024. CONCLUSIONS: Some complications such as the complications of the eye were not reported in all the countries. Therefore, it's recommended to determine the relative frequency of those complications in regions without such reports. The pooled estimates of different complications of brucellosis were different. There's a need for the standardization of the reporting of the complications of brucellosis to achieve comparability between studies and across different regions.

Brucellosis

Effectiveness of grief interventions in underrepresented regions: a systematic review and exploratory meta-analysis.

Background: Most evidence on grief and bereavement interventions originates from Western, Educated, Industrialized, Rich, and Democratic (WEIRD) populations, raising concerns about the generalizability and cultural relevance of existing findings in diverse global contexts. Individuals confronted with the death of a close person, particularly in cases of sudden or potentially traumatic loss, may be at increased risk of adverse psychological and physical health outcomes, highlighting the importance of effective interventions. This study aimed to synthesize evidence on the effectiveness of grief interventions in underrepresented regions.Method: A systematic search of Web of Science, APA PsycInfo, and Scopus, supplemented by manual reference checks, identified randomized controlled trials (RCTs) targeting bereaved individuals in underrepresented regions. Meta-analyses were conducted to estimate overall and subgroup effects based on control type, loss type, and intervention characteristics.Results: Fourteen RCTs comprising 1122 participants were included. Grief interventions demonstrated a significant moderate-to-large effect compared to control conditions (SMD&#x2009;=&#x2009;-0.74, 95% CI [-1.01, -0.47]). Substantial heterogeneity was observed (I&#xb2;&#x2009;=&#x2009;77%). No significant subgroup differences were identified.Conclusion: Grief interventions show promising effectiveness across diverse cultural and geographical contexts. However, the limited and heterogeneous evidence base highlights the need for more high-quality RCTs and for the development of culturally sensitive and contextually grounded approaches to mental health care in underrepresented regions.

Humans

Effects of passive blood flow restriction on muscle function following exercise-induced muscle damage in recreationally active males.

This investigation examined the effects of passive blood flow restriction (pBFR) on indices of exercise-induced muscle damage (EIMD) in recreationally active males. Fifteen males completed six consecutive visits (&#xb1;2&#x2009;hours). Participants completed 3&#x2009;&#xd7;&#x2009;25 maximal, unilateral, isokinetic (60&#xb0;&#xb7;s-1), concentric-eccentric leg extensions on both legs. Each leg was randomly assigned to receive pBFR (80% arterial occlusion pressure) or sham (20&#x2009;mmHg) at 0, 24, 48, 72, and 96&#x2009;hours post-EIMD. Perceived muscle soreness, range of motion (ROM), pain pressure threshold (PPT), concentric peak torque (CPT), and maximal voluntary isometric contraction (MVIC) torque were assessed and analyzed using separate linear mixed-effects models. Perceived muscle soreness increased at 24&#x2009;hours (mean difference [meandiff] = 4.9 au; p&#x2009;<&#x2009;0.001) and recovered by 96&#x2009;hours (p&#x2009;=&#x2009;0.482), with no differences between conditions (p&#x2009;=&#x2009;0.450). ROM (meandiff&#x2009;=&#x2009;-3.1&#xb0;; p&#x2009;=&#x2009;0.040), PPT (meandiff&#x2009;=&#x2009;-1.63 kgf; p&#x2009;<&#x2009;0.001), CPT (meandiff&#x2009;=&#x2009;-27.7&#x2009;Nm; p&#x2009;<&#x2009;0.001), and MVIC torque (meandiff&#x2009;=&#x2009;-30.8&#x2009;Nm; p&#x2009;<&#x2009;0.001) decreased at 24&#x2009;hours, with recovery occurring between 48-96&#x2009;hours. Condition-specific differences were observed for ROM (meandiff&#x2009;=&#x2009;2.5&#xb0;; p&#x2009;<&#x2009;0.001), PPT (meandiff&#x2009;=&#x2009;0.49 kgf; p&#x2009;=&#x2009;0.005), CPT (meandiff&#x2009;=&#x2009;6.2&#x2009;Nm; p&#x2009;=&#x2009;0.020), and MVIC torque (meandiff&#x2009;=&#x2009;7.1&#x2009;Nm; p&#x2009;=&#x2009;0.044), which were greater in pBFR than sham. These findings suggested that pBFR may reduce impairments in ROM, PPT, CPT, and MVIC torque following EIMD, despite a similar recovery trajectory between conditions.

Humans

Patient-reported outcomes in pediatric regional anesthesia trials: current use and limitations.

PURPOSE OF REVIEW: This review examines the current use and limitations of patient-reported outcome measures (PROMs) in pediatric regional anesthesia research. Despite the increasing emphasis on patient-centered outcomes, existing pediatric outcome assessment frameworks may inadequately capture the pain experience and interference with daily living. RECENT FINDINGS: Across 17 identified randomized controlled trials and 15 ongoing studies, PROM use remains highly variable, with consistent reliance on observational pain scales such as the Face, Legs, Activity, Cry, and Consolability scale and limited incorporation of standardized, longitudinal health-related quality-of-life measures. SUMMARY: Current pediatric PROM frameworks remain fragmented, limiting comprehensive evaluation of recovery. Greater standardization and incorporation of developmentally appropriate, longitudinal outcome measures are needed to better align clinical research with meaningful patient-centered endpoints and to improve assessment of functional and psychosocial recovery.

Humans

Relationship between menopausal hormone therapy and incidence risk of breast cancer: systematic review and meta-analysis.

BACKGROUND: Menopausal hormone therapy (MHT) is widely prescribed for alleviating menopausal symptoms. Prior studies have mainly focused on individual hormone therapy formulations. This meta-analysis comprehensively synthesized evidence across various regimens to systematically evaluate the association between MHT and breast cancer risk. MATERIALS AND METHODS: We systematically searched CNKI, Wanfang, PubMed, and Web of Science from inception through August 2024. Eligible studies examining breast cancer risk following MHT were independently screened and assessed by two reviewers. The review and meta-analysis followed PRISMA guidelines. RESULTS: Thirty-four studies were included. The random-effects model showed a significant but heterogeneous overall association (OR = 1.15, 95% CI: 1.09-1.22; I&#xb2; = 92.4%). Subgroup analysis identified hormone type, use status, and region as key determinants (P for interaction < 0.001). Stratification by hormone type resolved much of the heterogeneity, revealing risk confined to estrogen-progestin therapy (EPT; OR = 1.44, 95% CI: 1.26-1.64), while estrogen-only therapy (ET) showed no overall association (OR = 1.00, 95% CI: 0.91-1.10). Study type, region, and sample size were significant effect modifiers. For ET, randomized controlled trials demonstrated a protective effect (OR = 0.78, 95% CI: 0.70-0.87), contrasting with neutral findings from observational studies. CONCLUSIONS: MHT is associated with a modest but significant increase in breast cancer risk, primarily driven by EPT. This risk was not observed with ET in observational studies, though trials suggested a protective effect. Crucially, the association shows marked geographical heterogeneity, indicating risk is modified by regimen and regional factors.

Humans

Single-slice Functional Lung MRI During Metronome-Paced Tachypnea Detects Changes in Regional Ventilation Dynamics After a Single Dose of Dual Bronchodilator Treatment in COPD.

Dual long-acting bronchodilators are a standard treatment in chronic obstructive pulmonary disease (COPD), aimed at alleviating dyspnea, improving exercise tolerance, and preventing exacerbations. Metronome-paced tachypnea (MPT) offers a feasible alternative to exercise testing for the evaluation of dynamic hyperinflation (DH) in COPD. Because MPT can be performed during MRI, its combination with single-slice phase-resolved functional lung (PREFUL) MRI provides a promising approach to investigate changes in regional ventilation dynamics induced by DH. This approach was evaluated in a randomized, investigator-blinded, placebo-controlled, single-dose (SD) crossover trial with a two-week extension of once daily dual bronchodilator medication, in which patients with stable COPD underwent PREFUL MRI during resting tidal breathing (RTB) and during MPT. During RTB, no significant improvements in MRI-derived parameters were observed after SD treatment compared with placebo. During MPT, however, regional ventilation, flow-volume loop correlation, its defect percentage, and end-expiratory lung area improved significantly after SD treatment compared to the placebo scan (all p&#x2009;<&#x2009;0.02). After multi-dose treatment, five out of six measured parameters improved during MPT, when compared to the baseline scan without bronchodilator treatment (all p&#x2009;<&#x2009;0.03). In contrast to RTB, PREFUL MRI during MPT was able to detect changes in COPD patients already after SD treatment. The combination of MPT and PREFUL MRI represents a promising method to evaluate the effects of dual bronchodilators on regional ventilation dynamics and hyperinflation.

Humans

Access to maternity services for women asylum seekers and refugees: A transnational document analysis of international, European regional, and United Kingdom governance.

Women asylum seekers and refugees face persistent barriers to maternity care (antenatal, intrapartum and postnatal care) across high-income countries, yet the upstream governance shaping access remains under-examined. Although legally distinct, both groups share protection-seeking experiences and are addressed jointly in governance documents. This study examined and synthesised how international (macro), European regional (meso), and United Kingdom (UK, micro) governance documents frame and operationalise maternity service access. Sixty-four documents were analysed using the READ framework. Inductive analysis of macro and meso documents identified six access dimensions: universal coverage; cultural and linguistic adaptation; rights-based approaches; multi-agency collaboration; data, monitoring and accountability; and quality of care. These dimensions structured assessment of UK governance, with jurisdictions rated strong, moderate or weak. Alignment was fragmented: Wales, Scotland and Northern Ireland exempted asylum seekers from charging, whereas England retained charging provisions. Multi-agency collaboration was consistently articulated, yet none of the 35 UK government documents focused on maternity access for this population, and none required outcome monitoring disaggregated by asylum or refugee status. UK governance appears coordinated in form but fragmented in substance. UK-wide minimum standards and routine recording of these data, with safeguards against immigration-related use, could strengthen coherence and accountability and improve visibility of inequities.

Refugees

Regional and statewide hysterectomy-corrected endometrial cancer incidence and five-year relative survival in Texas.

BACKGROUND: Rising endometrial cancer (EC) incidence nationwide, particularly among Hispanic women, and high prevalence of risk factors such as obesity and comorbidities in Texas, motivated us to estimate EC incidence rates (IRs) and survival by age (<50 years/ early-onset, &#x2265;50 years/late-onset), race-ethnicity (Non-Hispanic-White [NHW], -Black [NHB], Hispanic), histology (endometrioid, non-endometrioid), and area-based socioeconomic (SES) factors across Texas Health Service Regions (HSRs). STUDY DESIGN: Between 2000 and 2019, a total of 42,571 women (20-79 years) with EC were reported from Texas within the Surveillance, Epidemiology, and End Results Program. IRs and 5-year relative survival were calculated using SEER*Stat. IRs were corrected for hysterectomy using Behavioral Risk Factor Surveillance System data. RESULTS: Statewide EC IRs rose from 38.5 (2000-2009) to 44.5 (2010-2019), with the highest increase in the Upper-South (42.6 to 53.8). Across HSRs, Upper-South consistently had higher IRs among women <&#x202f;50 (13.9) and &#x2265;&#x202f;50 years (112.7). Among those <&#x202f;50 years, Hispanics had the highest IRs (12.4), predominantly endometrioid tumors, whereas in women &#x2265;&#x202f;50 years, NHB had the highest IRs (119.2) with a large proportion of non-endometrioid tumors. IRs were higher in areas with lower poverty, and higher education, income, and urbanization. Associations with unemployment were mixed. Worse survival outcomes were observed among NHBs, non-endometrioid, advanced-stage, and lower SES. Central Texas had more favorable survival outcomes compared to other HSR. CONCLUSION: EC IRs and survival rates in Texas largely mirror national trends, with regional differences likely reflecting sociodemographic and histologic distributions.

Humans

Quantifying the combined effects of semi-closed terrain and monsoon on PM2.5 and O3 pollution aggregation in the North China Plain.

The North China Plain (NCP) and its surrounding regions represent one of the key priority areas for air pollution control. As anthropogenic emissions decline significantly, the effect of terrain and meteorology on air pollution pattern has become increasingly prominent, particularly given the NCP's unique semi-closed terrain and East Asian monsoon dynamics. However, quantitative characterization of terrain-dominated blocking effects remains unexplored. Here we quantitatively assess the blocking effects of mountains and terrain-coupled meteorological factors on air pollutant dispersion. We find the NCP on the eastern side of the Taihang Mountains showed high PM2.5 and O3 pollution levels, with winter PM2.5 and summer O3 high-value zones showing opposite north-south aggregation patterns. PM2.5 and O3 concentrations were highest in plains, followed by platforms, hills, and finally mountains. Within the 120-km buffer zones of the typical mountains in the NCP and its surrounding regions, PM2.5 and O3 concentrations increased initially with altitude but then decreased markedly above a threshold altitude. Above the threshold altitude, mountain blocking effects became dominant. The effective blocking altitudes of typical mountains in the NCP and its surrounding regions ranged between 22 and 929 m for winter PM2.5 pollution, and between 19 and 1060 m for summer O3 pollution. The Terrain-Wind Close Index indicates that the terrain-coupled East Asian monsoon showed stronger blocking effects on PM2.5 dispersion in southern NCP during winter and on O3 diffusion in northern NCP during summer, matching observed high-pollution zones. This study offers key insights for regional joint air pollution mitigation strategies, as well as regional pollution assessment.

Particulate Matter

Global epidemiology of diabetes and prediabetes in lean or non-obese patients with NAFLD: a systematic review and meta-analysis.

BACKGROUND: The presence of diabetes increases the risk of adverse outcomes of patients with non-alcoholic fatty liver disease (NAFLD) even in those with lean or non-obese NAFLD. However, the epidemiological data regarding the prevalence of diabetes and prediabetes in lean or non-obese NAFLD populations remain limited. We assessed the global epidemiology of diabetes and prediabetes in lean or non-obese patients with NAFLD. METHODS: Published studies were searched in PubMed, EMBASE, Cochrane Library, and Web of Science databases from the inception of the databases to October 2024. The pooled global prevalence of diabetes or prediabetes in patients with NAFLD was evaluated using random-effects meta-analysis. Subgroup meta-analysis and meta-regression were used to investigate potential sources of heterogeneity. RESULTS: A total of 54 studies involving 146,714 patients with non-obese or lean NAFLD were included. The pooled global prevalence of diabetes among patients with lean or non-obese NAFLD was 15.6% (95% CI 10.8%-22.7%). Studies from South America reported the highest prevalence (41.3%, CI 39.1%-43.5%). Meta-regression models showed that geographic region and mean age (p&#x2009;<&#x2009;0.05) were associated with the were associated with the prevalence of diabetes, jointly accounting for 51.61% of the heterogeneity. The global prevalence of prediabetes among patients with lean or non-obese NAFLD was 22.9% (95% CI 12.5%-41.9%) with the highest prevalence reported in studies from Europe (34.4%, CI 23.0%-51.4%). Meta-regression models showed that geographic region and country (p&#x2009;<&#x2009;0.05) were associated with the prevalence of prediabetes, jointly accounting for 73.65% of the heterogeneity. CONCLUSION: The pooled global prevalence of diabetes and prediabetes were 15.6% and 22.9% in lean or non-obese patients with NAFLD, respectively. These findings suggest the importance of diabetes screening in these patients.

Humans