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Effects of aerosol aging on composition and light-absorbance of nitrogen-containing organic compounds: Evidences from ultra-high-resolution mass spectrometry analysis.

Nitrogen-containing organic compounds (NOCs) are key components of particulate matter (PM), but their compositional evolution and light-absorbing properties during atmospheric aging remain poorly understood. In this study, ultra-high-performance liquid chromatography coupled with Orbitrap mass spectrometry was used to semi-quantitatively analyze 59 PM1 samples collected in Shanghai. NOCs accounted for 31 % and 64 % of the detected species in negative (ESI-) and positive (ESI+) ionization modes, respectively. Atmospheric aging significantly reduced the molecular diversity of polar organics, with both the number and mass concentration percentages of CHON- compounds showing significant negative correlations with aging degree. Van Krevelen analysis demonstrated a decrease in the number of carboxylic-rich alicyclic molecules and their CHON- contributions during the aging process (from 37.7 % in fresh samples to 21.2 % in aged samples). CHN+ compounds, a major NOCs group in ESI+ mode, also decreased with aging. Correlation analyses involving the Bep/(Bep+Bap) ratio, relative humidity, and mass absorption efficiency at 365 nm revealed a decline in light absorption capacity with aging, suggesting aqueous-phase oxidation as a dominant aging mechanism. CHON- and CHN+ compounds were identified as the principal light-absorbing constituents in PM1. This work provides new insights into the aging-induced transformations of NOCs in urban PM1, and their changing role in light absorption, highlighting the need for further investigation of the aging mechanisms of NOCs.

Aerosols

Spatially confined electrochemical strategy with DNA-assembled nanogaps for SNP detection.

Accurate detection of low-abundance single nucleotide polymorphisms (SNPs) against a large excess of homologous wild-type sequences requires both selective molecular recognition and effective transduction of small sequence differences into measurable signals. Here, we report a spatially confined electrochemical strategy that couples sequence-selective recognition with size-dependent mass-transport gating. DNA-hybridization-driven self-assembly of gold nanoparticles (AuNPs) forms a three-dimensional self-assembled electrode (3D-SAE) with a DNA-defined interparticle architecture. Competitive probes (SP/WP) convert single-base recognition into distinct molecular-size states: the SNP-associated pathway preferentially triggers a hybridization chain reaction (HCR), generating bulky AuNP-anchored HCR/methylene blue complexes (Au@HCR/MB) with reduced electrochemical accessibility through the porous 3D-SAE, whereas the wild-type pathway does not trigger HCR and maintains a high-current response from more readily accessible MB-containing species. Thus, sequence recognition is translated into a molecular-size difference and subsequently into an electrochemical signal through differential mass transport. Under buffer conditions, the platform achieved a statistically estimated detection limit of ∼0.47 fM and a quantitative range of 1 fM-100 pM. It discriminated a 0.1% mutant abundance in a fragmented genomic-DNA background. The downstream signal-transduction chemistry is enzyme-free and isothermal. This work establishes a mechanistical recognition-size-conversion-mass-transport-gating architecture for electrochemical nucleic acid analysis.

Polymorphism, Single Nucleotide

Bacteroides cellulosilyticus-derived 2-hydroxyphenylacetic acid rectifies hepatic lipid homeostasis in MASLD by targeting the PPARγ-CD36 axis.

The gut microbiota plays an important role in the occurrence and development of metabolic dysfunction-associated steatotic liver disease (MASLD), but the specific molecular mechanisms involved have not been fully elucidated. In this study, human cohort studies were performed to identify that the relative abundance of Bacteroides cellulosilyticus (B. cellulosilyticus) was significantly decreased in patients with MASLD. Through the integration of metagenomic and metabolomic analyses, it was confirmed that B. cellulosilyticus and its metabolite 2-hydroxyphenylacetic acid (2HPAA) are key factors regulating the occurrence and development of MASLD. Single-cell sequencing and lipidomic analyses revealed that 2HPAA can enter the liver through the enterohepatic circulation to exert regulatory effects. Specifically, 2HPAA inhibits the peroxisome proliferator-activated receptor γ (PPARγ) signaling pathway, thereby suppressing the expression of the fatty acid transporter CD36. Meanwhile, 2HPAA regulates lipid metabolism in hepatocytes by significantly enhancing palmitate conversion efficiency and inhibiting CD36 palmitoylation. This dual regulatory effect on CD36 expression and palmitoylation can reduce lipid accumulation in hepatocytes and ultimately alleviate MASLD progression. These findings reveal the mechanism by which B. cellulosilyticus and 2HPAA alleviate MASLD by targeting the PPARγ-CD36 pathway. This work provides a new perspective for the study of gut microbiota-host interactions in regulating liver diseases.

PPAR gamma

Influence of microplastics on microalgal performance during wastewater polishing.

Microplastics (MPs) are emerging contaminants that are increasingly accumulating in aquatic ecosystems due to excessive anthropogenic activity and insufficient mitigation strategies, posing serious environmental and public health risks. Their impact on wastewater (WW) treatment processes remains poorly understood. This study evaluated the effects of five MPs commonly found in WW - polypropylene, polystyrene, polyamide, low-density polyethylene, and high-density polyethylene - on the physiology and bioremediation performance of the microalga Chlorella vulgaris in synthetic WW (SWW). Metabolic responses were assessed via esterase activity and intracellular reactive oxygen species (ROS), while nitrogen (N), phosphorus (P), and glucose removal were monitored to evaluate bioremediation efficiency. MPs inhibited esterase activity and elevated ROS levels, indicating oxidative stress. Nevertheless, C. vulgaris maintained a high bioremediation capacity (> 75 % N, > 60 % P, and > 70 % for glucose). Environmental conditions modulated microalga response to MPs exposure. Under N-limited conditions, C. vulgaris exhibited enhanced nutrient uptake and biomass production, but a 12 h/12 h light/dark photoperiod reduced N removal but stimulated glucose consumption via heterotrophic metabolism. In contrast, C-limited conditions exacerbated oxidative stress and compromised nutrient removal, resulting in residual concentrations exceeding legal limits. These findings highlight that environmental factors can either mitigate or exacerbate the physiological stress induced by MPs, ultimately affecting WW polishing. This work provides a comprehensive insight into the cellular and metabolic effects of MPs on microalgae and supports C. vulgaris as a resilient and sustainable approach for nutrient and carbon removal in MP-contaminated WW systems.

Microalgae

Plasma proteomics: considerations for preanalytical variability; a systematic review with narrative synthesis.

BACKGROUND: The plasma proteome (PP) is a dynamic system subject to pathology-associated changes and a focus for novel disease biomarker discovery. Disease-related PP research assumes protein concentrations in test specimens accurately reflect the in vivo milieu. However, measures to maintain the physicochemical integrity of the proteome before assay are often rudimentary, poorly described, or lacking standardisation in published studies. Contrastingly, in laboratory medicine, there is an expectation that errors in the so-called "preanalytical phase" (PAP) that impact patient results are understood, monitored, and mitigated against, while also being well described in research publications. There is therefore scope for good practice from laboratory medicine to inform PP research workflows. This review considers factors in the PAP which may impact the validity of PP results. CONTENT: A systematic review was conducted per PRISMA guidelines, limited to English-language peer-reviewed studies (2014-2024). Candidate studies were imported, screened, and managed using Covidence systematic review software. SUMMARY: 15 eligible studies were reviewed, covering many relevant processes. 11 studies reported statistically significant differences in PP due to factors in the PAP. Temperature and time-to-processing were the most commonly reported factors affecting the PP, with significant effects reported in 8 studies. OUTLOOK: PAP variability can significantly affect results in PP studies. Careful consideration of the effect of each stage of the PAP is needed when working with the PP. In multicenter studies, pre-defined and research question-specific sample processing workflows are essential for reducing PAP variability, which helps ensure the validity of PP studies.

Humans

Game-Based Intervention for Bullying: Assessing the Efficacy of the REThink Therapeutic Game in Primary School Children.

Children's mental health issues can have a lasting effect into adulthood, including enhanced risks for their social and emotional development, as well as their academic performance and overall behavior. Worldwide nearly 1 billion children are affected by the bullying phenomenon, with social, emotional, and economic consequences. In this vein, our study aimed to analyze the effect of the therapeutic game REThink on the improvement of emotion regulation abilities and the reduction of both bullying behavior and victimization in primary school children. Our sample consisted of 75 children who were voluntarily enrolled by their parents, and randomly assigned to the intervention group (n = 38) or to the control group (n = 37). They completed the baseline assessment consisting of emotion regulation, irrationality, bullying and victimization behavior measurements, then the children from the intervention group played the therapeutic game REThink. Four weeks later, after completing each level twice, every participant had completed the same questionnaires at the post-test assessment. The results indicated significant changes across victimization for children who were exposed to verbal, physical or social bullying, increased emotional control and lower levels of irrationality, low frustration tolerance to work and demandingness, with small to medium effect size improvements for the REThink game group compared to the control group. The REThink therapeutic game proved to be a promising intervention tool for reducing victimization effects and irrationality, and improving emotion regulation abilities in primary school children. Future research could improve on these results by addressing the timeline stability limit.

Humans

Comparison of clinical outcomes of robotic versus open pyeloplasty in infants under 6 months.

INTRODUCTION: Robotic pyeloplasties have become the popular approach for surgical repair of ureteropelvic junction obstruction (UPJO) in the pediatric population. In infants less than 6 months old, there is concern for lack of intra-abdominal working space and lack of benefit compared to an open approach. Our aim was to compare the peri-operative and post-operative outcomes of patients undergoing open versus robotic pyeloplasty under six months of age. METHODS: A retrospective review was performed of patients less than six months of age undergoing robotic or open pyeloplasty between 2020 and 2024 at a single institution. Patient demographics and clinical outcomes were collected and compared. Surgical success was defined as a >50% reduction in the antero-pelvic diameter (APD) of the affected kidney at one year post pyeloplasty. RESULTS: A total of 32 patients were identified (16 robotic and 16 open), median age at surgery was 4 months old. There was no significant difference in length of hospital stay or narcotic usage between the two groups. The robotic cohort had a significantly longer operative time (209.5 min vs 142.5 min, p < 0.001) compared to the open cohort. There was no significant difference between post-operative complication or surgical success rates between the two groups. CONCLUSION: In this small series, robotic and open pyeloplasty both remain viable options for infants less than 6 months of age with equivalent surgical outcomes and lengths of hospital stay.

Humans

Degradation of a graphene-reinforced polyamide by fungi: When culture conditions matter.

The large-scale production, marketing and disposal of polymer-based graphene products can lead to the dispersal of graphene-enriched plastic particles into terrestrial ecosystems, where they might accumulate if not degraded by organisms. The objective of this work is to test the degradability and compatibility of one polyamide-6 polymer reinforced with reduced graphene-oxide (PA6-rGO) and its base constituents (polyamide-6, PA6; reduced graphene oxide, rGO) using mono- and co-cultures of two lignin-degrading fungi (Bjerkandera adusta and Morchella esculenta) grown under different nutrient conditions. Fungal (co-)cultures were exposed to pure rGO or abraded powders of PA6 and PA6-rGO in two different liquid media, and monitored over time for biomass growth, H2O2 production, and activity of two lignolytic enzymes (i.e., Laccase, Lac, and Lignin peroxidase, LiP). The changes in polyamide structure were evaluated by proton nuclear magnetic resonance and mass spectrometry, and changes in rGO were evaluated by Raman spectroscopy. The materials had no effect on fungal growth. PA6 increased Lac secretion only in low nutrient medium, while PA6-rGO slightly suppressed LiP activity. Only M. esculenta promoted polyamides oxidation when cultured in a low nutrient medium, as evidenced by a change in mass distribution values (m/z: 400-420) and the appearance of a new resonance peak (at 5.37 ppm). Lignolytic exudates in co-cultures low in nutrients caused a greater change in rGO, as shown by the increase in the ID/IG ratio. The degradation of rGO, PA6 and PA6-rGO depended on culture conditions.

Graphite

Integration of ear and hearing care services in low- and middle-income health systems: a systematic review and qualitative synthesis.

Hearing loss is a global public health burden and mostly affects those living in low- and middle-income countries (LMICs). One approach to address ongoing challenges is the World Health Organization's recommendation for the integration of ear and hearing care (EHC) services into healthcare packages. However, little is known about EHC integration approaches, particularly in LMICs additionally, these approaches have not been investigated through a health systems lens. This qualitative review aimed to describe the various approaches to the EHC service integration in LMICs and to identify enabling and constraining factors. We reviewed 17 studies, with a focus on LMICs, using adaptations of the Valentijn integration and World Health Organization EHC frameworks, following the PRISMA guidelines. Our investigation showed that most integration approaches were at micro or individual level. Enabling factors for integration of EHC services were training, mentorship, collaboration, technology, inclusion of EHC in healthcare packages and investment in EHC services. Barriers were challenges with training, facilities and equipment, policy implementation and resourcing of EHC services. We further described factors influencing healthcare seeking behaviour and the use of integrated EHC services, such as access and ability to pay, referral systems and communication and awareness. This study describes the complex nature of EHC integration and ways to support integration. Key considerations are the level of integration, training to address workforce issues and factors influencing service utilisation as we work towards health system strengthening.

Humans

Patient Ethnicity and Staff Use of Restraints and Restrictive Practice in Inpatient Psychiatric Services: A Systematic Review.

Restrictive practices such as restraints, seclusion, and forced medication are only intended to be used when the threat is at a level whereby an individual is likely to inflict harm on themselves or another individual. Demographic variations, including ethnicity, may be associated with the use of these practices. However, there is no systematic review on patient ethnicity specifically. The review therefore aimed to establish whether a patient's ethnic identity was associated with staff use of restrictive practices in inpatient psychiatric services. The systematic review followed the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Four databases were searched (PsycINFO, Medline, Embase, and CINAHL). Methodological quality was assessed using the Critical Appraisal Skills Program Checklists. Fifteen studies met the inclusion criteria. A variety of ethnicities were identified within the studies. These were driven by the location of the study. Seclusion (14 studies), forced medication (4), and physical restraint (4) were explored. There were mixed findings, with ethnicity shown to predict restrictive practices in studies having larger participant numbers, longer follow-up periods and less methodological bias. It remains unclear whether ethnicity is a genuinely independent predictor of restraint and coercive practices or interacts with other risk factors. Staff working in inpatient settings should be aware of how unconscious biases might affect clinical practice. Recruiting a diverse workforce from minority ethnic groups into inpatient psychiatric services would be a positive step. However, support for these staff members is important, and all staff should be equipped to respond to ethnic diversity. Future research should explore beyond patient-level factors.

Humans

Oxygen-controlled gamma-irradiation and annealing enable terminal processing of collagen-based biomaterials.

Gamma irradiation is a widely adopted method for terminal sterilization of medical devices; however, its application to collagen-based extracellular matrix (ECM) materials remains limited due to radiation-induced degradation of structural integrity and mechanical performance. Here, we present an engineered terminal-processing strategy that combines oxygen controlled gamma irradiation (25-30&#xa0;kGy) with post-irradiation dry-heat annealing to preserve ECM functionality while achieving effective sterilization. By modulating oxygen availability during irradiation, this approach alters radical reaction pathways, suppresses oxygen-mediated oxidative degradation, and generates a metastable radical-containing intermediate, which is subsequently converted into a structurally stabilized collagen network through thermal annealing. As a result, the treated matrices preserved ECM integrity and recovered clinically relevant mechanical properties. Furthermore, the process achieved cumulative viral reductions exceeding 6 log10 across a representative panel including enveloped and non-enveloped DNA and RNA viruses, demonstrating compatibility with sterility assurance and viral safety requirements for biologically derived medical devices. Notably, preliminary observations indicate that mechanical integrity can be partially preserved even at elevated irradiation doses up to 50&#xa0;kGy, suggesting potential applicability to sterilization validation frameworks requiring higher assurance levels. Overall, this work establishes a mechanistically grounded terminal-processing paradigm that enables control of radical fate, decouples sterilization efficacy from material degradation, and integrates sterilization, viral safety, and functional preservation into a unified and scalable framework for collagen-based biomaterials. This concept repositions gamma-irradiation from a purely degradative process to a controllable tool for tuning collagen structure and performance.

Gamma Rays

Contrasting redox-related physiological responses associated with HaGATA23 and HaGATA36 during Orobanche cumana parasitism in sunflower (Helianthus annuus L.).

Helianthus annuus is an economically important Asteraceae species used for seed oil production and ornamental purposes, but its production is seriously affected by the root-parasitic plant Orobanche cumana. GATA transcription factors are zinc-finger DNA-binding regulators involved in plant development and stress adaptation. However, the molecular characteristics of GATA transcription factors in Helianthus annuus and their contribution to Helianthus annuus -Orobanche cumana interaction remain poorly understood. Here, 36 HaGATA members were retrieved from the Helianthus annuus genome and classified into four phylogenetic clades. Chromosomal placement, collinearity, gene structure, motif composition, and promoter elements varied among the 36 HaGATA members, indicating evolutionary conservation coupled with functional diversification. Expression analysis and RT-qPCR analyses revealed differential expression patterns among HaGATA genes under O. cumana stress, with HaGATA23 markedly downregulated and HaGATA36 strongly upregulated. Overexpression of HaGATA23 was associated with increased malondialdehyde (MDA) accumulation and unfavorable changes in antioxidant enzyme activities, whereas its silencing showed the opposite physiological tendency. In contrast, overexpression of HaGATA36 reduced malondialdehyde accumulation, increased peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD) activities, while its silencing showed the reverse tendency. These results indicate that HaGATA23 and HaGATA36 are candidate genes associated with contrasting redox-related physiological responses during O. cumana stress. This work provides evidence that GATA transcription factors are associated with redox-related physiological responses in sunflower under O. cumana treatment and identifies HaGATA23 and HaGATA36 as functionally divergent candidate genes for further validation.

Helianthus

Predictive Validity of Violence Screening Tools in Emergency and Psychiatric Services: A Systematic Review.

Violence against healthcare staff, including a threat or an act of violence toward people during their work, poses a physical and psychological risk to workers internationally. Screening is an important strategy in preventing violence against healthcare professionals. The aim of this systematic review was to synthesize evidence on the predictive validity of risk assessment tools used to screen for violence and aggression risk toward healthcare workers in emergency and psychiatric departments (PD). Primary studies that examined the predictive validity of risk assessment tools for workplace violence were identified via a systematic search of Medline, PsycINFO, Embase, and the Cochrane databases. There were 62 eligible studies, ten of which had a lower risk of bias (RoB). Those studies with high RoB were primarily due to a failure to present calibration measures as part of the analysis. All included studies adopted a longitudinal design and were conducted in PDs. The ten highest-quality studies reported on eight different instruments, four of which showed acceptable to outstanding predictive performance. The Dynamic Appraisal of Situational Aggression and the Br&#xf8;set Violence Checklist showed the best predictive performance; they were also validated in emergency departments and are best suited for short-term risk prediction. We recommend that the selection of a risk assessment tool should consider the following: (a) the target population, (b) the violence operationalization, and (c) the purpose of the monitoring. We note that the use of a screening tool should be a part of a multicomponent strategy to ensure staff safety.

Humans

Efficacy of Proton Pump Inhibitor Therapy for Nocturnal GERD Symptoms and Associated Sleep Disturbances: A Systematic Review of Randomized Controlled Trials.

GOALS: A systematic review was conducted to evaluate the efficacy and safety of proton pump inhibitor (PPI) therapy in relieving nocturnal reflux symptoms and sleep disturbances. BACKGROUND: Nocturnal gastroesophageal reflux disease (GERD) is commonly associated with sleep disturbances. The benefits of PPI therapy for GERD-related nocturnal reflux and sleep disturbance remain unclear. STUDY: We searched the MEDLINE, EMBASE, and Cochrane CENTRAL databases from inception to March 1, 2026, for randomized controlled trials (RCTs) in adults with GERD and sleep disturbances that compared any PPI to placebo or an alternative therapy. The primary outcome was the proportion of patients experiencing relief from nighttime heartburn. Secondary outcomes included relief from GERD-related sleep disturbances, changes in subjective sleep quality, work productivity, and treatment-emergent adverse events (TEAEs). RESULTS: Five RCTs involving 1495 patients met the inclusion criteria. Three placebo-controlled trials consistently showed that PPI therapy improved nighttime heartburn relief and GERD-related sleep disturbances compared with placebo. Subjective sleep quality and sleep-related daytime functioning also generally improved with PPI therapy. However, the findings were more heterogeneous across trials because of differences in study populations, comparators, and outcome measures. Across the placebo-controlled studies, TEAEs were generally similar between the PPI and placebo groups. CONCLUSIONS: PPI therapy was associated with improvement in nighttime heartburn and reflux-related sleep disturbances, especially in patients with reflux-driven nocturnal symptoms. The available evidence also suggests potential improvement in subjective sleep quality and sleep-related daytime functioning.

Humans

Strategy for enhanced production of A40926B0 in Nonomuraea gerenzanensis using an efficient CRISPR/AsCas12f1 system.

The global emergence of vancomycin-resistant Gram-positive pathogens underscores the urgent need for efficient production of novel lipoglycopeptide antibiotics. Dalbavancin, a last-resort therapeutic agent, relies on its key biosynthetic precursor A40926B0, whose industrial manufacture is severely limited by the low yield of wild-type Nonomuraea gerenzanensis and inefficient genetic tools for this rare actinomycete. Here, we developed a high-efficiency CRISPR/AsCas12f1 genome editing system and applied systematic metabolic engineering to boost A40926B0 biosynthesis. First, conjugation conditions were optimized to elevate the transfer efficiency in N. gerenzanensis D11. The hypercompact AsCas12f1 nuclease showed markedly lower cytotoxicity than SpCas9 and enabled 100% gene deletion efficiency with preferred PAMs (TTTG, CTTG, GTTG). Second, we strengthened the shikimate pathway via multiple genetic strategies: overexpressing feedback-resistant DAHP synthase (aroG fbr ) and chorismate mutase/prephenate dehydrogenase (tyrA fbr ), as well as knocking out pheA. This manipulation blocks the phenylalanine synthetic branch and redirects metabolic flux toward the l-tyrosine branch. Third, we engineered the branched-chain fatty acid (BCFA) pathway via promoter replacement of bkdA2B2C2, LipAB, fabF and deletion of acdH to enhance isododecanoyl side-chain supply. The combinatorial engineering yielded strain B-13, which produced 1740&#x202f;mg/L A40926B0 in shake flasks. Finally, 50-L fed-batch fermentation with continuous maltodextrin feeding further increased the titer to 1817&#x202f;mg/L, the highest reported titer to date. This work establishes a robust CRISPR editing tool for N. gerenzanensis and provides valuable engineering references for precursor-oriented strain improvement targeting lipoglycopeptide antibiotics, offering insights for the industrial scale production of A40926B0.

A40926B0

Timing of OMERACT core domain measurement in gout clinical trials: a systematic review of randomised trials.

AIMS: The Outcome Measures in Rheumatology (OMERACT) initiative has endorsed core domain sets for gout trials. The aims of this study were to evaluate the time points and frequencies at which the gout core domains are measured in existing gout urate-lowering therapy and gout flare trials, and whether all collected measurements were reported. METHODS: Urate-lowering therapy (n = 29) and gout flare randomised clinical trials (n = 14) from 2005 were identified from a prior systematic review of core domain reporting. Data were extracted for the time points and frequencies at which each core domain was measured, as well as whether all collected measurements were reported. RESULTS: In urate-lowering therapy trials, the core domains were measured at seven different frequencies. Serum urate and gout flares were most commonly measured monthly, and tophus burden was most commonly measured three monthly. Reporting of all collected measurements varied, from 24/29 (83%) trials for serum urate to 0/2 (0%) trials for activity limitation. In gout flare trials, core domains were measured at nine different frequencies. Pain, joint tenderness and joint swelling were most commonly measured monthly. Reporting of all collected measurements varied, from 13/14 (93%) trials for pain to 3/8 (37.5%) trials for joint tenderness. CONCLUSION: In both urate-lowering therapy and gout flare trials, there is substantial variability in when the core domains are measured, and reporting of collected measurements is inconsistent. This work provides the foundation for a consensus process to establish standardised time points and frequencies for measuring the OMERACT-endorsed gout core domains.

Gout

Genome-wide identification of the HSP70 superfamily in tropical sea cucumber Stichopus monotuberculatus and their expression analysis under low-salinity stress.

Heat shock proteins (HSPs) are a group of evolutionarily conserved molecular chaperones that serve as indispensable core regulators in preserving cellular homeostasis and orchestrating organismal stress responses. The tropical sea cucumber Stichopus monotuberculatus, a high-value aquaculture species, is sensitive to fluctuations in environmental salinity-a challenge that has emerged as a critical bottleneck limiting its large-scale commercial cultivation. However, no systematic investigation has been conducted to characterize the HSP70 superfamily in S. monotuberculatus and elucidate its functional roles in salinity adaptation. In the present study, we performed a comprehensive genome-wide scan and identified 19 HSP70 superfamily genes in the S. monotuberculatus genome, with the HSP70IV subfamily showing remarkable gene expansion, containing 8 distinct copies. Phylogenetic analysis, conserved motif identification, and gene structure characterization demonstrated high evolutionary conservation within each HSP subfamily. These genes were unevenly distributed across the chromosomes of S. monotuberculatus, and prediction of cis-acting elements revealed that their upstream regulatory regions were enriched with numerous functional elements associated with stress response and immune regulation. Salinity stress experiments revealed that under severe low-salinity conditions (18&#x2030;), the expression levels of SmHSPA14L and multiple HSP70IV subfamily members were significantly elevated, while SmHYOU1D was significantly downregulated; in contrast, only subtle changes were detected in the expression of most HSP70 genes under moderate low-salinity stress (24&#x2030;). These findings strongly suggest that HSP70 genes, particularly the expanded HSP70IV subfamily, may act as key modulators in the low-salinity stress response. This work provides valuable insight into the molecular mechanisms underlying salinity adaptation in tropical sea cucumbers.

Animals

Enhancement of secondary organic aerosol formation from isoprene photooxidation by ammonia.

Ammonia (NH3) can participate in atmospheric secondary organic aerosol (SOA) formation by reacting with organic acids and carbonyl compounds in particle phase, but its influence on the gas phase chemistry remains unclear. This study performed a series of smog chamber experiments to investigate the influence of NH3 on the formation of SOA from isoprene photooxidation by OH radicals. Both gas and particle phase products were measured with a series of state-of- art instruments including a nitrate ion chemical ionization mass spectrometer (nitrate-CIMS) and high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS). Our results showed that in the presence of NH3 SOA in the chamber significantly increased, along with an enhanced oxidation of isoprene. CIMS analysis further showed that NH3 in the chamber homogeneously reacts not only with gas-phase organic acids but also with gaseous low volatility oxygenated organic molecules (OOMs) to generate extremely low volatility and ultralow volatility NH3-OOMs clusters. Quantum chemical calculation showed that NH3 can spontaneously interact with OOMs to form NH3-OOMs clusters by forming hydrogen bonds with RCOOH, R-OOH, and R-OH. These clusters can promote new particles formation and particle growth through nucleation and condensation, directly enhancing the isoprene SOA production with a contribution of 78% to the enhanced SOA. Moreover, the formation of NH3-OOMs clusters also results in more isoprene consumed by OH radicals, indirectly increasing the SOA production with a contribution of 22 % to the enhanced SOA. Our work for the first time clarified a synergetic effect of NH3 on isoprene SOA formation, which should be accounted for by models.

Aerosols