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Pathways of onward HIV disclosure in relationships among young people living with vertically acquired HIV receiving antiretroviral therapy: A qualitative analysis from the BREATHER Plus trial, South Africa.

For young people living with HIV (YPLHIV) navigating their status since birth, managing onward disclosure of a potentially stigmatising condition in relationships is challenging, and may or may not lead to social support, with implications for wellbeing. In a clinical trial setting in KwaZulu-Natal, South Africa, we investigate how young people living with vertically acquired HIV navigate onward disclosure. Data were from the qualitative component of the BREATHER Plus randomised controlled trial evaluating the efficacy, safety and acceptability of short-cycle dolutegravir/tenofovir-based triple antiretroviral therapy (ART) in young people aged 12-19 years. We analyse data on 35 participants receiving ART engaged in clinical trials at the research site: 29 in longitudinal in-depth interviews (IDIs) and 12 across three focus group discussions (FGDs), including 6 in IDIs and FGDs. The Disclosure Processes Model was applied in the thematic analysis. Pre-disclosure was characterised by social assessments of potential confidants. During disclosure, reciprocal vulnerability and partial information-sharing were employed. Post-disclosure processes entailed linear and non-linear feedback trajectories, impacting future disclosures. The findings show that the study cohort of young people receiving ART navigated many bidirectional disclosure pathways to maintain social connections in relationships, and counselling guidelines need to be responsive to this.

Humans

How is goal setting used in interventions for chronic disease prevention and management in sub-Saharan Africa? A systematic review and narrative synthesis.

Non-communicable diseases are increasingly prevalent in sub-Saharan Africa, and goal setting is often used to promote healthy self-management behaviours. In this review, we aimed to synthesise literature around how goal setting is used, for application in future interventions in the region. A systematic search was conducted in six databases and results screened for eligibility. Study characteristics, intervention details, goal setting components, feedback from participants and facilitators were extracted. Data were analysed using narrative synthesis and thematic analysis. The Mixed Methods Appraisal Tool was used to assess study quality. We included 24 publications describing 18 unique interventions. Included studies were of high to moderate methodological quality. Goal setting intervention components were informed by a variety of frameworks and involved a range of tasks. Interventions were often facilitator-led; many were conducted in group settings. Participants reported goal setting as useful for putting self-management into practice but encountered challenges related to language and literacy levels. Adequate detail on goal setting intervention components was not always present. Through this review, we provide a comprehensive picture of the variability of goal setting approaches in chronic disease prevention and management in sub-Saharan Africa and recommend more standardised use and reporting of goal setting intervention components.

Humans

Characteristics of post-exercise responders versus non-responders following aerobic or isometric exercise in physically inactive adults of African and South Asian descent with high-normal blood pressure or grade I hypertension.

OBJECTIVE: To investigate interindividual variability in post-exercise hypotension (PEH) and to characterise cardiovascular and autonomic differences between responders and non-responders following aerobic and isometric exercise in adults of African and South Asian descent with elevated blood pressure (BP). METHODS: Physically inactive adults of African and South Asian descent living in Suriname (18-65 years) with high-normal BP or grade I hypertension participated in a randomised controlled crossover trial. In this randomised cross-over trial, 47 adults (50.1 ± 10.8 years; 38% male) with high-normal blood pressure or grade I hypertension completed three conditions: aerobic exercise (30 min at 40-60% heart rate reserve), isometric handgrip exercise, and a non-exercise control. Ambulatory BP was assessed over 24 h. PEH was defined as the net effect: (post-exercise - pre-exercise) - (post-control - pre-control). Participants were classified as responders if daytime BP decreased ≥5 mmHg. Arterial stiffness, cardiac, and autonomic parameters were assessed. RESULTS: Following aerobic exercise, 46% of participants were classified as systolic responders compared with 28% after isometric exercise. No baseline differences were observed in demographic or clinical characteristics between responders and non-responders, suggesting that PEH variability may reflect underlying physiological rather than clinical differences. Aerobic responders demonstrated greater reductions in aortic augmentation index (-19.4% vs. -10.9%, p = 0.05), larger increases in stroke volume (+8.1 vs. -5.3 mL, p = 0.05) and cardiac output (+1.54 ± 1.89 vs. +0.58 ± 1.60 L/min, p = 0.009), and more favourable autonomic recovery. Among all variables, only the change in cardiac output was associated with PEH magnitude (r = -0.46, p = 0.006). No consistent physiological differences were observed following isometric exercise. CONCLUSION: PEH following aerobic exercise is characterised by a distinct responder phenotype associated with greater reductions in aortic augmentation index and favourable cardiac adaptations. These findings highlight substantial interindividual variability in BP responses and support the need for individualised exercise strategies in hypertension management.

Adolescent

Changes in sexual behavior among women in studies evaluating the dapivirine vaginal ring for HIV prevention.

BACKGROUND: Access to novel HIV prevention technologies often raise concerns of risk compensation. This analysis examined changes in the sexual behaviors of MTN 020/ASPIRE participants, a placebo controlled randomized control trial, who subsequently enrolled in MTN-025/HOPE, an open-label extension using the dapivirine vaginal ring. METHODS: Both studies enrolled healthy, sexually active, HIV-negative women from Malawi, South Africa, Uganda and Zimbabwe. Longitudinal data on participants' sexual behaviors, specifically sex with a nonprimary partner (past 3&#xa0;months), and use of male or female condoms at the last vaginal sex act were compared between ASPIRE and HOPE. Conditional and mixed ordinal logistic regression models evaluated associations between study and sexual behaviors at enrollment,&#xa0;and quarterly over the first 12&#xa0;months. RESULTS: Of the 2629 individuals enrolled in ASPIRE, 1456 (55%) participated in HOPE. At enrollment, the proportion of participants who reported sex with a nonprimary partner and condom use at last vaginal sex act did not differ by study. Across all quarterly follow-up visits, sex with a nonprimary partner was more common in HOPE (13.9-18.7%) than ASPIRE (10.7-12.6%); adjusted OR&#xa0;1.47, 95% CI 1.24-1.75, P&#xa0;<&#xa0;0.001. There was no difference in condom use at the last vaginal act across all quarterly follow-up visits between ASPIRE (36.5-42.7%) and HOPE (43.6-46.7%); adjusted OR&#xa0;1.05, 95% CI 0.94-1.18. CONCLUSION: More women reported sex with nonprimary partners in HOPE, with little change in condom use over time between the two studies. Understanding behavior changes during PrEP use allows for tailored, holistic reproductive health programming.

Humans

Chlorfenapyr-pyrethroid nets for pyrethroid-resistant malaria vectors: efficacy, resistance risks, and policy implications.

The Global Technical Strategy for Malaria 2016-2030 aims to reduce malaria incidence and mortality by 90%, yet widespread pyrethroid resistance among major malaria vectors in sub-Saharan Africa threatens this goal. Thus, the World Health Organization recommends chlorfenapyr-pyrethroid combination nets as a priority intervention where pyrethroid resistance undermines vector control. This systematic review synthesizes evidence on the performance, emerging resistance risks, and policy implications of these next-generation insecticide-treated nets. A structured search of literature from 2010 to 2024 across PubMed, Embase, WHO IRIS, and Google Scholar identified 31 eligible studies from 113 records. Evidence shows that chlorfenapyr-pyrethroid nets consistently outperform pyrethroid-only nets against resistant Anopheles populations, demonstrating a 1.8-fold increase in mosquito mortality (95% CI: 1.5-2.1). Community trials report 40-60% reductions in malaria infection incidence and entomological inoculation rates following deployment. However, early signs of chlorfenapyr resistance have emerged in Anopheles gambiae populations in Central Africa (RR: 2.4, p&#x2009;=&#x2009;0.01), linked to CYP6P4 metabolic overexpression. A significant correlation was also observed between agricultural pesticide use and vector resistance patterns (r&#x2009;=&#x2009;0.62, p&#x2009;<&#x2009;0.05). Although chlorfenapyr-pyrethroid nets provide an important short-term tool for managing pyrethroid resistance, their long-term effectiveness depends on integrated resistance management. Rotational deployment with other insecticide classes, strengthened genetic and phenotypic surveillance, and a coordinated 'One Health' approach involving both public health and agriculture are essential to sustain gains and advance progress toward the 2030 malaria targets.

Pyrethrins

Psychotherapy training in psychiatry: a systematic review and narrative synthesis on the supervision experiences of early-career psychiatrists.

BACKGROUND: Supervision is a fundamental component of psychotherapy training, transforming theoretical knowledge into clinical skills through real-world practice. Psychotherapy training practices vary widely between countries, training programs, and over time, including supervision. Our systematic review aimed to investigate and describe the experiences of psychotherapy supervision through early-career psychiatrists' (ECPs) views. METHODS: We systematically searched PubMed/MEDLINE, Scopus, and PubPsych for survey-based studies on ECPs' experiences of psychotherapy supervision during or after their psychiatry training and reported our findings according to the PRISMA guidelines. Of 32,877 articles screened, 29 articles were included. Each article underwent quality assessment, and results were synthesized narratively. RESULTS: Included articles published between 2000 and 2025, were from Europe (N = 16, 55.1%), the Americas (N = 5, 17.2%), Western Pacific (N = 4, 13.7%), South-East Asia (N = 2, 7%), Eastern Mediterranean (N = 1, 3.5%), and Africa (N = 1, 3.5%), with a total of 4691 participants. Supervision access rates ranged from 26.2% in Nigeria to 85.5% in Russia, with significant variation across countries and psychotherapy modalities. Most ECPs received 50-100 total hours of supervision, frequently delivered in weekly sessions. While formats, individual, group, or mixed, varied by country and training scheme, supervision was generally provided by a psychiatrist-psychotherapist. Common learning techniques included oral consultations and case discussions, followed by audio recordings or transcripts. The need to self-fund psychotherapy supervision costs was identified as a prominent barrier. CONCLUSIONS: Psychotherapy supervision is inconsistent globally, with barriers including supervisor availability and cost. There is a large implementation gap between recommendations and evaluated practice. Digital tools and competency-based frameworks may improve access and quality.

Humans

Microplastic contamination in South Asian commercially important seafood: A comprehensive assessment of occurrence, source, and human health risk.

Seafood is a cornerstone of global food security and human nutrition, serving as the primary source of animal protein for more than one-fourth of the global population, with South Asia representing one of the world's fastest-growing seafood-consuming regions. However, escalating microplastic (MP) pollution in marine ecosystems poses an emerging threat to seafood safety and human health, yet a comprehensive regional assessment of MP contamination in South Asian seafood remains lacking. This study presents the first region-wide systematic synthesis of the literature on MP contamination in commercially important seafood across South Asia, integrating occurrence patterns, human exposure assessment, polymer-specific hazard evaluation, and bibliometric analysis to address this critical knowledge gap. The meta-analysis estimated an average microplastic exposure of 145&#xa0;particles/person/day through seafood consumption in South Asia, with fish contributing the highest intake (121 particles/person/day). The detected polymers were classified into PHI hazard levels I-IV, with polyvinyl chloride (PVC), polyurethane (PU), and polyacrylamide (PAM) representing the highest hazard categories. The mean pollution load index (PLI) was 7.71 (Category I), with crustaceans exhibiting the highest contamination (PLI&#xa0;=&#xa0;10.07). Polypropylene was the predominant polymer, whereas fragments and blue particles were the most frequently reported microplastic characteristics. These findings provide the first regional baseline for assessing microplastic contamination, polymer-associated hazards, and human exposure through seafood consumption in South Asia, underscoring the need for standardized monitoring and targeted mitigation strategies to safeguard seafood safety and public health.

Animals

Effectiveness of tobacco cessation interventions delivered in clinical settings in South Asia: a systematic review and meta-analysis.

BACKGROUND: Despite the burden of tobacco use, access to cessation support in South Asia remains scarce. OBJECTIVE: This review evaluates the effectiveness of tobacco cessation interventions delivered in clinical settings in South Asia. METHODS: Five relevant databases were searched from inception to February 2025. Eligibility criteria included randomized and non-randomized studies evaluating behavioral, pharmacotherapy, and multicomponent interventions delivered in clinical settings in South Asia. Data on study setting and design, participant information, intervention, comparator, and outcomes were extracted. Meta-analyses using random-effect models were conducted where possible. Certainty of evidence was assessed using GRADE. RESULTS: Thirty-seven studies were included (22 randomized and 15 non-randomized). Interventions involved pharmacotherapy (n&#x2009;=&#x2009;6; 16.2%), nicotine replacement therapy (n&#x2009;=&#x2009;7; 18.9%), behavioral counseling (n&#x2009;=&#x2009;12; 32.4%), or combined/multicomponent interventions (n&#x2009;=&#x2009;12; 32.4%). Most studies were conducted in India (n&#x2009;=&#x2009;26; 70.3%), followed by Pakistan (n&#x2009;=&#x2009;6; 16.2%), Nepal (n&#x2009;=&#x2009;3; 8.1%), and two studies (5.4%) were multi-country in India, Pakistan, and Bangladesh. Pooled analyses demonstrated higher quit rates among intervention versus control for continuous abstinence at 0-3&#x2009;months (RR: 1.21, 95%CI: 1.06 to 1.37) and >3&#x2009;months (RR: 1.68, 95%CI: 1.1.4 to 2.47), and for point abstinence at >3&#x2009;months post-intervention (RR: 2.03, 95%CI:1.35 to 3.08). Heterogeneity was high for all analyses (I2 range: 94% to 97%). Combined behavioral and pharmacotherapy interventions were most effective (RR: 1.70, 95%CI: 0.98 to 2.92), although not statistically significant (p&#x2009;=&#x2009;0.06). CONCLUSION: Tobacco cessation interventions delivered in clinical settings in South Asia are effective, particularly when combining behavioral support with pharmacotherapy. However, evidence is limited by methodological weaknesses.

Humans

Non-motor symptoms and healthcare utilization before diagnosis of myasthenia gravis: a nationwide cohort study.

BACKGROUND: Non-motor symptoms have been reported prior to myasthenia gravis (MG) diagnosis. However, the temporal patterns of non-motor symptoms and healthcare utilization before MG diagnosis remain unclear. METHODS: We conducted a retrospective, population-based cohort study using the Korean National Health Insurance Service (KNHIS) database from 2011 to 2021. Incident MG cases were identified using the International Classification of Diseases, Tenth and Rare Intractable Disease codes. Individuals younger than 20&#xa0;&#xa0;years or with missing health screening data were excluded. Each MG case was matched 1:10 by age, sex, and index date to controls. Non-motor symptoms and healthcare utilization were defined using operational criteria derived from KNHIS claims data. Rate ratios (RRs) and 95&#xa0;% confidence intervals (CIs) were estimated across four prespecified intervals (0-1, 1-2, 2-5, and 5-10&#xa0;&#xa0;years) before MG diagnosis. RESULTS: We included 8,355 MG patients and 83,550 controls (mean age, 53.7&#xa0;&#xa0;years; male, 44&#xa0;%). MG patients had higher rates of any non-motor symptoms over 10&#xa0;&#xa0;years(RR 1.34; 95&#xa0;% CI 1.30-1.39), with the sharpest increase in the year before diagnosis. Depression, anxiety, migraine, constipation, and insomnia consistently showed higher RRs across all intervals. Hospitalizations (RR 1.66; 95&#xa0;% CI 1.61-1.71) and outpatient clinic visits (RR 1.10; 95&#xa0;% CI 1.04-1.17) were consistently higher across 10&#xa0;&#xa0;years, peaking during the 0-1 year before MG diagnosis. CONCLUSION: Non-motor symptoms and healthcare utilization increased years before MG diagnosis. Earlier recognition of these symptom patterns may facilitate timelier evaluation for MG and improve diagnostic pathways.

Humans

Genome-wide insights into the evolutionary and demographic history of the red alga Mazzaella laminarioides: Evidence for speciation with ancient migration along the southeast Pacific coast.

The mechanisms driving lineage divergence in red algae remain unexplored, despite the group's remarkable diversity and ancient evolutionary history. The red alga Mazzaella laminarioides, a Chilean intertidal species complex composed of three parapatric cryptic lineages (North, Center, South), offers a valuable system to evaluate these processes, as its life history combines severe dispersal limitation with a haploid-diploid cycle that may influence the emergence of reproductive barriers. We reconstructed its evolutionary history using whole-genome sequencing and nuclear genome assembly of representative individuals from each lineage. Phylogenomic analyses based on 1,507 single-copy orthologs recovered three deeply divergent lineages with limited nuclear discordance consistent with incomplete lineage sorting. For both splits, demographic modelling was most consistent with an Ancient Migration scenario, although support over strict isolation was moderate, suggesting that divergence may have begun with low asymmetric ancestral gene flow followed by subsequent loss of connectivity, demographic bottlenecks, and later population expansion. Coding sequence analyses revealed lineage-specific dN/dS heterogeneity; only one South-lineage locus passed FDR correction (metaxin-1, mitochondrial protein import), with two further South-lineage candidates in chlorophyll and heme biosynthesis falling below the FDR threshold. Together, these signals suggest that divergent selective pressures on energy acquisition may have contributed to divergence at the southern end of the distribution. These results add to the small but growing body of whole-genome data for red algae and, alongside recent macroalgal studies, suggest that ancestral connectivity could be a recurrent feature of lineage divergence even in marine organisms with extremely restricted dispersal.

Rhodophyta

Dissemination of blaKPC-3-harbouring Klebsiella pneumoniae across ST48 and ST628 in multiple healthcare facilities in the Republic of Korea.

Klebsiella pneumoniae carbapenemase-3 (KPC-3) remains rare in South Korea, where KPC-2 is the dominant carbapenemase, making the repeated detection of a concentrated blaKPC-3 signal over five years notable. We performed genomic analyses of blaKPC-3-harbouring K. pneumoniae from a regional healthcare network. Two chromosomally distinct lineages with concordant capsule loci (ST628/KL15 and ST48/KL62) presented multidrug-resistant phenotypes, and the virulence-associated loci were confined to ST48. Single-nucleotide polymorphism (SNP) analyses revealed near-clonal relatedness within lineages, with 0-38 pairwise SNPs among ST628 isolates and 8 SNPs between the two ST48 isolates. Core-genome multilocus sequence typing (cgMLST) supported this structure, as ST628 isolates were assigned to complex type 19149 with 0-7 allelic differences, and ST48 isolates were assigned to complex type 19150 with 5 allelic differences. These patterns support vertical spread via clonal expansion across multiple facilities. Despite substantial chromosomal separation, most isolates carried the same IncFII(K) plasmid backbone and blaKPC-3, and they were nearly indistinguishable from a plasmid previously reported in South Korea. One isolate carried blaKPC-3 on a distinct multireplicon IncFIB(K)/IncFII(K) plasmid, indicating that the signal was not confined to a single plasmid backbone. In both plasmids, blaKPC-3 was embedded within Tn4401b. These findings indicate that a rare blaKPC-3 genotype can persist regionally through sustained clonal dissemination and that cross-lineage linkage is compatible with past horizontal transfer involving a conserved plasmid. These findings underscore the need for subtype-resolved, regionally coordinated genomic surveillance in connected healthcare networks to detect uncommon carbapenemase variants early.

Klebsiella pneumoniae

The impact of the COVID-19 pandemic on osteoporotic fractures: a systematic review and meta-analysis.

BACKGROUND: Recent reports suggest that the COVID-19 pandemic and associated lockdowns may have influenced the epidemiology of osteoporotic fractures, but results vary across regions and fracture types. The aim of this study was to provide evidence-based insights into the impact of the pandemic on osteoporotic fracture incidence. METHODS: We searched four databases (PubMed, Embase, Cochrane Library, and Web of Science) up to August 2025 for observational or retrospective studies comparing osteoporotic fracture incidence during the COVID-19 pandemic (2020) with the pre-pandemic period (2019). The primary outcome of interest was the change in fracture incidence, analysed using risk ratios (RR) with 95% confidence intervals (CI) in Review Manager 5.4. Subgroup analyses were performed by sex, geographic region, and fracture type. RESULTS: Nine studies meeting the inclusion criteria were analysed. Overall, "all types" of osteoporotic fractures showed a significant decrease during the pandemic (RR = 0.85, 95% CI 0.80-0.91, p&#x2009;<&#x2009;0.0001). Specifically, forearm fractures decreased significantly (RR = 0.87, 95% CI 0.79-0.96, p&#x2009;=&#x2009;0.002). However, for the most clinically significant fractures, no statistically significant global change was found for hip fractures (RR = 0.93, 95% CI 0.76-1.15, p&#x2009;=&#x2009;0.14) or vertebral fractures (RR = 1.35, 95% CI 0.85-2.15, p&#x2009;=&#x2009;0.20). In regional subgroup analysis, hip fracture incidence decreased significantly in South America (RR = 0.79, p&#x2009;=&#x2009;0.0004) and in both males and females, but no significant change was observed in Europe (RR = 0.92, 95% CI 0.81-1.04, p&#x2009;=&#x2009;0.17). CONCLUSION: During the COVID-19 pandemic, there was a decrease in the incidence of minor fractures, such as those of the forearm, likely due to reduced outdoor activity. However, the incidence of major osteoporotic fractures (hip and vertebral) remained stable globally, with significant reductions observed only in specific regions like South America.

Humans

Mitochondrial DNA diversity in Ecuadorian populations: Recurrence of variant 16136 within haplogroup B2.

The identification of lineage-defining variants, frequently found in the coding region of mitochondrial DNA (mtDNA), is essential for refining haplogroup classification. Most mtDNA studies in South American populations have focused on the control region (CR), which has provided important insights into population structure and maternal lineage origins, although information needed for more robust phylogenetic resolution has been neglected. This study investigates the maternal genetic structure of Ecuadorian populations by combining CR and whole mitogenome analyses. Sequences from the mtDNA CR were obtained from 461 individuals (253 Mestizos and 208 Native Americans), while complete mitogenomes were sequenced for 127 individuals to improve phylogenetic resolution by identifying lineage-defining variants present in coding region. Most mtDNA haplogroups in the two population groups analyzed were of Native American origin (A2, B2, B4, C1, D1, D4), with significant differences in the distribution of specific lineages between them. Among Mestizos, African haplogroups (all within the L branches) and Eurasian haplogroups (H, K, R, U) were detected at low frequencies, whereas no African lineages were observed among Native Americans. The results obtained highlighted a heterogeneity within Ecuadorian populations that must be considered when developing mtDNA haplotype databases for forensic purposes. Whole mitogenome sequences enabled the identification of variants that refined haplogroup classifications, provided a more accurate reconstruction of the maternal genetic diversity, and improve the discrimination between Native American and Asian maternal lineages within haplogroup B4b.

Humans

Genome-wide SNP data support species boundaries in sympatric Polylepis Ruiz & Pav. (Rosaceae) species from Bolivia and Ecuador.

Species delimitation in the South American genus Polylepis is notoriously challenging due to high morphological similarity and phenotypic plasticity, likely driven by hybridization and gene flow. Previous phylogenetic studies suggested that genetic structure aligns more strongly with geography than with taxonomy, questioning existing species concepts and hampering conservation efforts. We used double-digest RAD sequencing (ddRADseq) to generate genome-wide SNP data for 11 Polylepis species sampled across multiple localities in Bolivia and Ecuador. Population genetic analyses, phylogenetic inference, and network approaches were combined to assess whether genetic structure aligns more closely with taxonomy or geography. Morphologically defined species formed largely cohesive genetic lineages across regions, with species identity explaining substantially more genetic variation than locality. While localized admixture and reticulation were detected among closely related taxa, widespread species showed strong genetic cohesion and clear separation from congeners. Our results indicate that the sampled Polylepis species from Bolivia and Ecuador maintain distinct genetic identities despite localized signals consistent with gene flow. This genome-wide support for current taxonomy highlights Polylepis as a valuable model for studying speciation under gene flow and indicates that multiple geographic sampling will be essential in reconstructing a robust phylogeny of the genus, with important implications for conservation planning in Andean montane forests.

Bolivia

Antarctic Peninsula soil carbon stock and efflux: A complex interplay of soil properties and heavy metals.

This study establishes a quantitative framework for understanding surface soil carbon dynamics and ecosystem connectivity in Fildes Peninsula and Ardley Island, King George Island, South Shetland Islands, Antarctic Peninsula. The mean soil organic carbon (SOC) stock across all study sites was 1.10 &#xb1; 1.93 kg C/m&#xb2;. Restricting net carbon balance analysis to Fildes Peninsula, where soil respiration (Rs) data were available, yielded a site-specific SOC stock of 0.45 &#xb1; 0.45 kg C/m&#xb2;. Scaling Rs to a realistic 120-day active season and assuming stable SOC stocks resulted in estimated annual carbon loss of 15 g C/(m2&#xb7;yr), equivalent to 3.3 % of standing SOC. Comprehensive sensitivity analyses spanning plausible winter respiration (0 %-20 % of summer rates) and annual change in SOC stocks (-1 %-2 %) consistently supported a net carbon sink, with turnover rates constrained to 3.3 %/yr-4.7 %/yr. Principal component analysis showed that ornithogenic processes as the dominant control on SOC, total nitrogen (TN), zinc (Zn), copper (Cu), and cadmium (Cd) provide a clear multivariate signature of marine-derived nutrient, while Pb was decoupled from this gradient and associated instead with fine-particle size controls. These results reveal dual but independent drivers of soil metal enrichment in this region. Despite their limited spatial extent, ornithogenic soils store disproportionately large carbon pools. Overall, this integrated analysis reveals how marine-terrestrial subsidies regulate Antarctic carbon cycling and provides a quantitative and reproducible framework for assessing carbon dynamics under ongoing climate change.

Antarctic Regions

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