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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 (&#x394;14C), CO2 stable isotopes (&#x3b4;13C, &#x3b4;18O), 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 (&#x394;14C + CO/CO2 and &#x394;14C + CO2 stable isotopes) for source apportionment. Results show that during the dry season, particularly in March-April, atmospheric &#x394;14C 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 &#x394;14C values coincided with regional wildfire activity. Monte Carlo results attributed up to &#x223c;34 %-60 % of local CO2 to biomass burning in April, followed by March with contributions of &#x223c;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

Building phenotypic character matrices for phylogenetic inference: exploration of 35&#x2009;years of practice.

Recent methodological development in phylogenetic inference has focused predominantly on molecular data. However, renewed interest in other data types, particularly morphological data, has followed from the increased recognition of the power of total evidence and tip-dating approaches, including fossil data, for inference of time-scaled trees and rates of evolution. However, attention has largely focused on the improvement of models of morphological evolution and other analytical tools with much less discussion about data acquisition itself. Here we review past and current practice for describing and collecting morphological data for phylogenetic inference. We present a systematic review of 164 phylogenetic analyses conducted over the last 35&#x2009;years and focused on a diverse group of extinct arthropods: trilobites. Trends in increasing matrix size, data type, and coding strategy are evident. Where present, polymorphic characters have been predominantly derived from discretized continuous characters, although increasingly practitioners are utilizing alternative approaches for the treatment of quantitative characters. Not surprisingly, traditional indices that describe character consistency are highly correlated with matrix size but show surprising variation at different taxonomic scales. More recent attempts to describe data quality using information theory imply that characters can have high information content even if data are missing for many tips, providing support against the exclusion of characters because of missing data. In consideration of this, as well as advances in the study of developmental biology and variational complexity, we identify several avenues for increasing the quality and quantity of morphological data going forward.

Phylogeny

Differences in Radiological Risk Perceptions Following Online and In-Person Workshops.

Nuclear energy is widely regarded as a critical part of the pathway toward a secure, low-carbon electricity grid, yet long-term management of used nuclear fuel remains a persistent challenge. Although technically viable options for interim and consolidated storage exist, public concern and community opposition - rooted in historical distrust and risk perception - continue to complicate siting decisions. In response, recent federal efforts have emphasized collaboration-based approaches and community engagement, though empirical evidence on the effectiveness of different engagement strategies remains limited. This study examines how the structure and delivery of community engagement influence changes in public attitudes toward hosting interim used nuclear fuel storage facilities. Using survey data from 13 educational workshops around the United States, we evaluate: (1) the inclusion of trust-building content prior to technical content, and (2) engagement format, comparing online and in-person workshops. Analyses focus on participant changes in perceptions of safety, risk, and support for hosting, using the Wilcoxon rank-sum test and other non-parametric hypothesis tests on surveys conducted before and after workshops. Results indicate that workshop participation is associated with some measurable attitude changes, with significant (p < 0.05) differences in response variability for some questions across workshop formats. In particular, when comparing nuclear energy to other clean energy sources, in-person workshop participants are substantially more likely to gain a more favorable opinion of nuclear energy than online participants. These findings contribute empirical evidence on how trust-building and delivery mode shape outcomes in public engagement on complex and contested energy policy issues such as storage of used nuclear fuel.

nuclear fuel cycle

Pervasive hybridization and introgression in Diervilleae (Caprifoliaceae).

Diervilleae (Caprifoliaceae) is a horticulturally important lineage with striking floral diversity and a long history of interspecific crossing, suggesting reticulate evolution. We integrated nuclear SNPs and whole plastome data to reconstruct a phylogenomic backbone for the tribe and to identify hybrids, cultivated accessions, and introgression among lineages. Nuclear and plastid phylogenies consistently recover Weigela and Diervilla as reciprocally monophyletic and resolve four major lineages within Weigela, providing a reproducible framework for revising sectional limits and species boundaries. Cultivated accessions form a well supported clade sister to W. florida and show predominantly W. florida ancestry while retaining contributions from multiple wild lineages, consistent with recurrent crossing, backcrossing, and selection. Analyses of wild populations reveal recurrent hybrids and enable plausible parental combinations to be inferred. Tests across the genome further indicate strong evidence for historical introgression across Diervilleae, with the strongest signals involving W. middendorffiana, W. maximowiczii, and Diervilla. Fossil evidence, divergence time estimation, and paleodistribution modelling together suggest range expansion during the Miocene and Pliocene followed by climate driven contraction, providing a spatiotemporal context for episodic contact, introgression, and the East Asia-North America disjunction.

Hybridization, Genetic

The identification of growth-promoting lncRNAs in oral cavity squamous cell carcinoma.

Oral Cavity Squamous Cell Carcinoma (OCSCC) is an aggressive tumor that develops within the mouth of patients. Tumor-suppressor gene loss and genomic arrangements fuel tumorigenesis and transcriptional reprogramming. Understanding how these alterations contribute to OCSCC growth and cell survival may identify new therapeutic vulnerabilities or biomarkers. We profiled the role of long non-coding RNAs (lncRNAs) in the growth of three OCSCC cell lines using a CRISPRi-screen and identified 19 lncRNAs that contribute to OCSCC proliferation. By comparing these lncRNAs to other screens, we find that these lncRNAs are uniquely required in OCSCC and not other malignancies. We show that these lncRNAs are abundantly expressed in OCSCC cells and tumors. Independent testing of candidate lncRNAs confirms their role in supporting OCSCC growth. Our results show that a novel subset of lncRNAs are required for the growth of OCSCC cancer cells and that these lncRNAs are cell lineage specific.

CRISPRi

Metabolic engineering of Candida yeasts for biotechnological applications.

Candida yeasts represent a versatile yet underexploited platform for industrial biotechnology. These yeasts utilize a remarkably broad range of carbon sources, particularly for hydrophobic carbon sources, coupled with robust growth and diverse biosynthetic capacities, making them promising hosts for sustainable production of chemicals, fuels, and proteins. Despite these advantages, industrial deployment of Candida species has been hindered by concerns regarding opportunistic pathogenicity and the historical lack of efficient genetic manipulation tools, leading to a substantial gap between metabolic potential and practical utilization. Recent advances in functional genomics, genome editing, and systems metabolic engineering are rapidly overcoming these barriers, enabling more precise and efficient strain development. In this review, we systematically summarize recent progress in the metabolic engineering of Candida species as microbial cell factories, with particular emphasis on expanding genetic toolkits, utilizting renewable and non-conventional carbon sources, and biosynthesizing high-value compounds. In addition, we propose a biosafety-oriented classification framework to support their safe industrial deployment. Finally, we discuss current challenges and emerging opportunities, emphasizing that the synergy of synthetic biology and artificial intelligence-driven design holds the key to unlocking the biotechnological potential of Candida yeasts.

Candida

Air Pollution and Heat Impacts on Respiratory Morbidity and Mortality Outcomes in Africa: A Systematic Review Towards a Meta-analysis.

PURPOSE OF THE REVIEW: This review synthesised evidence on associations between air pollution and respiratory morbidity in Africa. Following PRISMA guidelines, we systematically searched PubMed, ScienceDirect and Elicit for case-control studies published between 2015 and 2025. RECENT FINDINGS: Thirteen studies from ten African countries reported pollutant levels far exceeding WHO guidelines. Indoor PM&#x2082;.&#x2085; in biomass-using homes ranged from 96 to 177&#xa0;&#xb5;g/m&#xb3;, and ambient PM&#x2082;.&#x2085; reached 259&#xa0;&#xb5;g/m&#xb3;. Nitrogen oxides were consistently associated with reduced lung function in children, while household air pollution increased risks of under-five mortality and low birthweight. Associations with acute respiratory infections varied across settings. Vulnerability was greatest among young children, those with airway hyperresponsiveness, and households with poor ventilation. Only three studies included temperature, and none examined heat-respiratory interactions. Across African case-control studies, particulate matter and household air pollution remain consistently linked to adverse respiratory outcomes, highlighting urgent needs for cleaner fuels, improved ventilation, and stronger evidence on combined pollution and heat exposures.

Humans

Temporal evolution of minimally invasive pediatric urolithiasis treatment over 30 years.

Urolithiasis in children has increased substantially over the past 30 years, and surgical management maintains an important role in treatment. Technological advances such as lasers and miniaturization have broadened treatment options, and researchers investigate the best indications for each procedure. The aim was to identify publication trends in the field and explore reasons why Extracorporeal Shockwave Lithotripsy is being gradually less applied in the treatment of pediatric urolithiasis. A Reverse Systematic Review of the literature was conducted regarding the surgical treatment of urolithiasis in children. Five databases were screened, gathering all articles from inception that were evaluated in systematic reviews. We examined 123 publications, 197 reports, and 15,878 procedures, consisting of the largest studied population in the field. There was an increasing number of publications, although in progressively less prestigious journals. The number of studies on miniaturized percutaneous techniques and flexible ureteroscopy has increased closely with the rise in popularity of these procedures worldwide, mainly driven by studies from Asia, Europe, and North America. A trend of self-renewed interest is fueled by technological innovation and has led to fewer publications on Extracorporeal Shockwave Lithotripsy over the years. This review highlights the fact that, despite positive results in recent studies, the low popularity of ESWL within the scientific community is driving a decline in the technique's indications. Moreover, based on the findings of this study, key research priorities include continued reporting of high-quality outcomes, and technological progress in ESWL would contribute meaningfully to the field.

Humans

Surveilled subjectivation: narratives of drug policing among people who use prohibited drugs in Sweden.

In Sweden, possession and personal use of drugs are criminalized since 1988, resulting in police work being directed towards minor drug offenses. Despite this, police and other authorities are encouraged to protect the health and wellbeing of people who use prohibited drugs (PWUPD). Knowledge is scarce on how this drug policy plays out in practice. This study therefore analyzes interviews with 20 PWUPD who visited harm reduction services and interacted with policing agents in Stockholm, Sweden. The analysis is based on the participants' narratives of drug policing, and it concerns how they produced themselves as subjects through relations between materiality and discourse. We utilize the concept of surveilled subjectivation to elucidate what the participants could do, what they knew and who they could be or become under drug policing. Four themes were identified illustrating the link between discourse and materiality in PWUPD's surveilled subjectivation: "Material aspects of surveillance"; "Resisting the 'drug abuser' identity"; "Fighting power with power"; and "Crossing boundaries and becoming-other". The participants described nonstop efforts to prevent their bodies, activities, belongings and environments from being enfolded by drug law enforcement, which otherwise would fuel even more surveillance. They therefore disassociated themselves from the "drug abuser" identity, and managed encounters with policing agents by keeping a low profile or acting compliantly. While the study highlights the skills and knowledges the participants deployed to navigate omnipresent drug policing, we conclude that their production of autonomous and empowered subjectivities would be facilitated if possession and use of drugs were no longer criminalized.

Humans

Trends in demographic and health survey publications based on a bibliometric analysis.

BACKGROUND: The Demographic and Health Surveys (DHS) Program, launched in 1984, provides high-quality population health data that underpins a vast body of global health research. However, the scale and growth patterns of DHS-based publications remain underexplored, particularly as donor funding uncertainties threaten program sustainability. OBJECTIVE: We examine temporal trends in DHS-based research output from 1984 to 2025, quantifying growth patterns and publication delays to inform understanding of the program's global research expansion. METHODS: A systematic bibliometric review was conducted following PRISMA guidelines across PubMed, Scopus, Web of Science, Dimensions, Wiley, and CINAHL. Eligible peer-reviewed articles using DHS data between 1984 and 2025 were identified. Annual publication counts were analyzed, segmented regression identified growth inflection points, and timeliness was assessed by calculating lag between survey completion and publication. RESULTS: Over 10,000 DHS-based publications were identified. Annual output rose from isolated studies in the 1980s to several hundred annually by the 2010s. Segmentation analysis revealed two rapid growth phases: a 56-publications/year increase from 2004-2012, and a 71-publications/year increase from 2012 to 2024. Despite this growth, median lag from survey completion to publication remained approximately 5 years, with only a modest recent improvement (Kendall's &#x3c4;&#x2009;=&#x2009; -0.623, p&#x2009;<&#x2009;0.001). CONCLUSION: DHS data have fueled exponential growth in global health research over four decades, confirming their vital role in evidence generation. However, persistent publication delays highlight the need to shorten the pathway from data collection to dissemination through strengthened research capacity in low- and middle-income countries. Sustained funding is essential to maintain this critical evidence source.

Bibliometrics

Pollution characteristics and health risks of PAHs and OPAHs in PM2.5 of an inland basin city in China under the influence of the clean air action plan.

Since the implementation of China's Clean Air Action, remarkable progress has been made in air pollution control, with continuous air quality improvement in Xi'an, a typical inland basin city in the Fenwei Plain. To clarify winter organic aerosol pollution variations and pinpoint targeted control needs under policy regulation, this study investigated PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) and oxygenated derivatives (OPAHs) in winter Xi'an, focusing on pollution levels, chemical compositions, source contributions, meteorological impacts, regional transport and health risks. Historical comparison showed generally lower wintertime PAH concentrations in Xi'an during the period of China's clean-air actions. PMF results indicated mixed source influences on PAHs and OPAHs, with biomass-burning-related mixed combustion showing the largest contribution. During haze episodes, absolute concentrations of both PAHs and OPAHs increased; the increase was statistically significant for OPAHs but not for parent PAHs, while 4-5 ring PAHs and BcdPQ dominated the PAH and OPAH profiles, respectively. Meteorological variability, particularly synoptic pressure patterns, was strongly associated with pollutant concentrations, and regional pollution was dominated by in-basin accumulation combined with short-range transport from northern Shaanxi industrial zones. Haze periods exhibited higher toxic-equivalent concentrations, with OPAHs, particularly BcdPQ, dominating the toxicity-equivalent burden. Screening-level ILCR estimates generally remained below 10&#x207b;4 but increased during haze episodes, especially for adult and elderly groups. In conclusion, China's clean air actions have coincided with lower wintertime PAH pollution, but stronger control of residential biomass and other solid-fuel combustion, traffic emissions, and OPAH formation remains necessary in the Fenwei Plain.

China