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PubMed2026

Efficacy of citicoline as an add-on therapy in Parkinson's disease: a randomized, double-blind trial.

BACKGROUND: Citicoline is a promising therapeutic option for improving both motor and non-motor symptoms in Parkinson's disease (PD) beyond levodopa and other standard dopaminergic treatments. OBJECTIVES: The CITIPARK study evaluated the efficacy and safety of citicoline in improving clinical outcomes and quality of life (QOL) in PD patients on dopaminergic therapies. METHODS: The randomized, double-blind, multicenter trial compared citicoline (1000 mg/day intramuscular, two six-week cycles) with placebo for 24 weeks in PD under stable medications. The primary endpoint was change in Movement Disorder Society-Unified PD Rating Scale (MDS-UPDRS) total score; secondary endpoints included motor and non-motor subscores, QOL, clinical global impression (CGI) and safety. RESULTS: The study enrolled 485 participants, randomizing 474 (citicoline: 303; placebo: 171). Citicoline significantly increased the likelihood of achieving a minimal clinically important difference compared with placebo (OR 2.06, 95% CI 1.06-3.99; P = 0.031) on the MDS-UDPRS total score in the modified intention-to-treat population. Among secondary outcomes, the citicoline group showed greater improvement in motor function (MDS-UPDRS III -2.97 vs -0.13; p = 0.009) and a greater improvement on CGI -II and CGI-III (3.26 vs 3.59; p = 0.021 and 9.30 vs 10.38; p = 0.018, respectively). AEs occurred in 22.1% and 27.1% of the citicoline and placebo groups, respectively. CONCLUSIONS: Citicoline was well tolerated and associated with motor benefits compared with placebo in a highly compliant population. The results suggest a role of citicoline as a safe and possibly effective supportive therapy in PD treated with concomitant dopaminergic agents.

Humans↗

PubMed2026

Effects of intradialytic nutrition on dialysis adequacy and fatigue in hemodialysis patients: a randomized crossover study.

OBJECTIVE: To assess intradialytic nutrition's effects on dialysis adequacy and fatigue in maintenance hemodialysis patients. METHODS: A randomized, two-period, two-sequence, self-controlled crossover trial was conducted in two outpatient hemodialysis centers in Türkiye. Thirty-six patients were randomized; 32 completed both periods. The participants received standardized intradialytic nutrition in one period and no food intake during the control period. Dialysis adequacy was evaluated using the urea reduction ratio and single-pool Kt/V. Intradialytic blood pressure was recorded during dialysis sessions, and fatigue severity was measured using the Piper Fatigue Scale at the end of each period. RESULTS: No significant differences were observed in dialysis adequacy or fatigue scores between the two periods. Intradialytic nutrition was associated with greater reductions in systolic and diastolic blood pressure, particularly during the second hour of dialysis. No clinically relevant adverse events occurred. CONCLUSION: Intradialytic nutrition did not compromise dialysis adequacy or worsen fatigue severity but was associated with increased intradialytic blood pressure reductions. Individualized clinical decisions and careful hemodynamic monitoring are warranted when implementing intradialytic nutritional interventions. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT07687498.

Humans↗

PubMed2026

The combined and independent influence of food texture and a 'mindful eating' instruction on eating rate and food intake among Dutch primary schoolchildren.

Eating rate (ER), the amount of food consumed per unit of time, is a key determinant of food intake, with faster ER associated with larger meal size. Research in adults has shown that both sensory properties like texture, and instructions can influence ER and intake. However, their independent and combined effect on ER and intake in children remain poorly understood. This study examined the effects of food texture and a 'mindful eating' instruction on ER and food intake in children. Children (N = 73), 38 boys, aged 4-12 years, participated in a 4-week cluster-randomized incomplete cross-over study conducted during regular school lunches. Using a 2×3 factorial design, children were exposed to two levels of food texture (softer vs. harder whole-grain buns) and three types of instructions (none, control, 'mindful'). Linear mixed models with repeated measures were used, adjusting for sex and group. As the interaction between food-texture and type of instructions was non-significant, it was excluded from the final models. Results revealed a strong main effect of food texture on ER and food intake (all p < 0.001), where compared with softer buns, harder buns were associated with a slower eating rate (Δ = -6.67 g/min, SE = 0.59) and reduced food intake (Δ = -70 g, SE = 8). In contrast, type of instruction had no significant effect on ER or intake (p = 0.85). Our findings demonstrate that food texture exerts a dominant influence on children's eating rate and food intake, highlighting texture modification as a potential leverage point for influencing ER and intake in children.

Humans↗

PubMed2026

Qualitative evidence of service user experiences and perspectives on long-acting injectable buprenorphine for opioid treatment - a scoping review.

BACKGROUND: There is substantial literature on opioid treatment program (OTP) formulations and how they relate to the pharmacotherapy service user experience. As a newer formulation, less is known about service user experiences of long-acting injectable buprenorphine (LAIB). The aim of this scoping review is to map the qualitative evidence and gaps in the literature on service user experiences and perspectives of LAIB. METHODS: Our search strategy included Medline, Embase, PsycINFO, CINAHL, Scopus and Web Science, and citation chaining, from January 2016 to June 2025. Studies were included if reporting qualitative descriptions of LAIB service user experiences of treatment for opioid dependence, inclusive of qualitative, mixed methods (description of qualitative data only), case reports and English language. Articles were screened by two reviewers. A living experience first author led the analysis using inductive coding and thematic analysis, to produce a descriptive summary of synthesised findings alongside key study characteristics and quality appraisal, adhering to the Systematic reviews and Meta-Analysis for Scoping Reviews (PRISMA-ScR) checklist. RESULTS: After screening 838 titles/abstracts and reviewing 150 full texts, 40 studies met the eligibility criteria. All were conducted in high income countries, principally the US (n=12); Australia (n=10); and England and Wales (n=9). We identified five themes: Navigating LAIB treatment; Embodied and relational effects of LAIB; Impact and role of the service provider; Narratives of harm reduction and recovery; Stigma and criminalisation. LAIB was commonly experienced as increasing convenience, stability and freedom from daily supervised dosing, enabling improved work, travel, privacy and social participation. Reduced clinic/dosing contact often lessened enacted stigma and treatment burden. However, experiences were heterogenous. Some participants described injection-site discomfort, uncertainty about dose adequacy, reduced flexibility once injected, and ambivalence about LAIB effects. There was inconsistency in LAIB service user reports on service connection, isolation and psychosocial support. Treatment experiences were strongly shaped by provider practices. CONCLUSIONS: Findings underscore the need for integrated, flexible, harm-reduction oriented and person-centred LAIB treatment models that prioritise choice, autonomy and therapeutic relationships to maximise benefit for service users. However, evidence of LAIB service user experiences is concentrated in high-income countries, and the absence of perspectives from low- and middle-income country settings represents a substantial gap in the evidence base.

LAIB↗

PubMed2026

Effects of extended problem-based learning interventions on undergraduate nursing education: A systematic review.

OBJECTIVE: Exploring the effects of long-term PBL (problem-based learning) intervention on undergraduate nursing students. METHODS: The article retrieved literature from CINAHL Complete, Academic Search Complete, Web of Science, PubMed, EMBASE, OVID, and Cochrane Library up to January 2025. Studies had to meet all of these criteria: (1) They used a randomized controlled trial (RCT) and quasi-experimental design. (2) The PBL pedagogy intervention lasted 4 weeks or longer. (3) The participants were undergraduate nursing students. (4) They reported primary outcomes. These included critical thinking, problem-solving skills and self-directed learning. Two researchers screened articles, extracted data, and assessed quality independently using blinding. They used Cochrane ROB2 for RCTs and ROBINS-I for quasi-experimental studies to judge bias risk. Meta-analysis was performed using RevMan 5.4 software. For continuous variables, standardized mean difference (SMD) and 95% confidence interval were calculated. Heterogeneity was assessed by I2 statistic. When I2 > 50%, sensitivity analysis was conducted. The source of heterogeneity was explored by excluding studies one by one. The primary outcomes included standardized critical thinking, problem-solving, and self-directed learning assessment results. RESULTS: A total of 11 randomized controlled trials and quasi-experimental studies were retrieved and included for meta-analysis. The experimental group significantly outperformed the control group in critical thinking, problem-solving, and self-directed learning, with differences being statistically significant (P ≤ 0.05). However, high heterogeneity was observed. After sensitivity analysis, the heterogeneity was reduced and the results remained statistically significant, indicating that the findings were not solely dependent on the excluded studies.

Problem-Based Learning↗

PubMed2026

Risk factors for loss of skeletal muscle mass in patients with chronic kidney disease on a low-protein diet.

OBJECTIVES: A low-protein diet (LPD) is recommended for patients with chronic kidney disease (CKD) to prevent a further decline in renal function. However, its impact on muscle mass in these patients remains unclear. This study investigated the risk factors for loss of muscle mass in patients with CKD on an LPD. METHODS: Eighty-four patients with predialysis CKD (59 men, mean age 61.9 ± 11.5 y) who participated in a multicenter randomized controlled trial initiated in 2014 were retrospectively reviewed. We collected data on baseline blood and urine tests, body composition, and dietary records at the start and end of the observation period. We evaluated muscle mass using the skeletal muscle index (SMI) and analyzed risk factors for a decrease in SMI during the 24-wk observation period, using logistic regression analysis. Variables with an association (P < 0.1) in univariate analysis, as well as age, sex, use of low-protein rice, and changes in protein intake, were subjected to multivariate analysis. RESULTS: SMI decreased in 50 patients (59.5%) during the observation period. Multivariate analysis identified significant associations of the SMI with serum albumin at baseline (odds ratio 0.11, 95% confidence interval 0.02-0.52, P = 0.004) and changes in energy intake while on the LPD (odds ratio 3.39, 95% confidence interval 1.00-11.43, P = 0.049). CONCLUSIONS: Risk factors for reduced SMI in patients with CKD on an LPD were malnutrition when initiating the LPD and reduced energy intake during its implementation. Clinicians should optimize nutritional status before initiation of an LPD and ensure adequate energy intake throughout treatment.

Humans↗

PubMed2026

Which radiographic plane should be used to quantify the distal tibia angle on weightbearing CT images?

BACKGROUND: Precise quantification of distal tibial alignment is essential for planning corrective osteotomies and ankle joint replacement surgery. The lateral distal tibial angle (LDTA) is the principal radiographic parameter used for this purpose. While LDTA is increasingly measured on weightbearing cone-beam CT (WBCT) using two-dimensional coronal slices, the optimal measurement plane remains unclear. METHODS: In this retrospective comparative study, full-leg WBCT scans of patients scheduled for supramalleolar osteotomy (n = 20; mean age 47 ± 12.8 years) were analyzed. LDTA was measured on three coronal planes of the distal tibial plafond (anterior edge, mid-dome, posterior edge) and compared with semi-automated three-dimensional (3D) tibial alignment measurements as the reference standard. RESULTS: Mid-dome LDTA showed no significant difference from the 3D reference (p > 0.05) and demonstrated excellent agreement. Anterior measurements significantly overestimated LDTA, while posterior measurements underestimated it (both p < 0.05), with only fair agreement. CONCLUSION: LDTA should be measured at the mid-dome of the distal tibial plafond on WBCT to ensure accurate and reproducible alignment assessment. LEVEL OF EVIDENCE: Level III - Retrospective Comparative Study.

Humans↗

PubMed2026

Effects of comprehensive oral care on nasogastric tube removal in long-term care residents with dysphagia: A multi-center randomized controlled trial.

Oral care is essential for residents in long-term care (LTC) facilities to reduce complications such as aspiration pneumonia. While routine oral hygiene is standard practice, comprehensive oral care (COC)-which includes facial and intraoral muscle massage, salivary gland stimulation, and oral moisturization-may further enhance swallowing function. However, evidence linking COC directly to nasogastric (NG) tube removal remains limited. This study evaluated the effectiveness of COC in facilitating NG tube removal and improving swallowing function among LTC residents with dysphagia. A multicenter, open-label randomized controlled trial was conducted across eight LTC facilities. The intervention group (n = 40) received daily one-on-one COC sessions lasting 30-40 min, while the control group (n = 37) received routine oral hygiene. Participants were followed for six months, with outcomes including NG tube removal, swallowing function, body weight, and pneumonia incidence. At six months, the COC group demonstrated a significantly higher NG tube removal rate, with eight participants achieving full oral intake (p = 0.005). Functional Oral Intake Scale scores were also significantly higher in the intervention group (p = 0.005). Time to NG tube removal ranged from 17 to 182 days. Under intention-to-treat principles, the NG tube removal rate remained significantly higher in the COC group (16.7%vs. 0%, p = 0.005). Competing risks analysis using the Aalen-Johansen estimator confirmed a 6-month cumulative incidence of NG tube removal of 14.6% in the COC group versus 0% in the control group (Gray's test: p = 0.005), with no significant between-group difference in mortality (p = 0.500). No significant differences were observed in body weight change or pneumonia incidence between groups. Among participants who successfully discontinued NG tube use, dementia was the most common underlying condition. These findings suggest that daily one-on-one COC is a feasible intervention in LTC settings and may improve swallowing function while facilitating NG tube removal in residents with dysphagia.

Humans↗

PubMed2026

Deciphering S-nitrosylation-regulated metabolic networks in postmortem beef based on label-free modificomics: Identification of ferroptosis as a novel quality-related pathway.

This study elucidated the molecular mechanisms of S-nitrosylation on postmortem beef metabolism and quality based on the label-free modificomics. Varying degrees of S-nitrosylation were exogenously induced in beef semimembranosus (SM) muscle. Results indicated that a high S-nitrosylation level significantly increased beef pH and Warner-Bratzler shear force (WBSF) while reducing centrifugal loss (P < 0.05). A total of 828 S-nitrosylated proteins and 1458 modification sites were identified, of which 114 sites on 81 proteins (DSNPs) exhibited differential modification abundance, representing an increase of 125% compared with previous proteomics studies. DSNPs were mainly involved in glycolysis, the tricarboxylic acid cycle, oxidative phosphorylation, calcium signaling, cell structure, and ferroptosis. Notably, this study provides the first evidence in postmortem muscle that S-nitrosylation regulates key ferroptosis-related proteins, including ACSL, CP, and TF, offering new insights into the link between S-nitrosylation and the ferroptosis pathway in meat. Correlation analysis demonstrated that TF was significantly negatively correlated with pH and WBSF, but positively correlated with centrifugal loss (P < 0.05). Collectively, protein S-nitrosylation critically modulates postmortem beef quality through the coordinated regulation of multiple metabolic processes. More importantly, the identification of ferroptosis as a S-nitrosylation-sensitive pathway provides a new perspective for regulating meat quality through protein post-translational modifications.

Animals↗

PubMed2026

Statistical test to compare the linkage model and the admixture model based on central limit results.

In the Admixture Model, the probability that an individual carries a certain allele at a specific marker depends on the allele frequencies in K ancestral populations and the proportion of the individual's genome originating from these populations. The markers are assumed to be independent. The Linkage Model is a Hidden Markov Model that extends the Admixture Model by incorporating linkage between neighboring loci. We prove consistency and asymptotic normality of maximum likelihood estimators for the ancestry of individuals in the Linkage Model, complementing earlier results by (Pfaff et al., 2004; Pfaffelhuber and Rohde, 2022; Heinzel, 2025) for the Admixture Model. These results are used to prove that a statistical test that allows for model selection between the Admixture Model and the Linkage Model is an asymptotic level-α-test. Finally, we demonstrate the practical relevance of our results by applying the test to real-world data from The 1000 Genomes Project Consortium (2015).

Genetic Linkage↗

PubMed2026

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 PM₂.₅ in biomass-using homes ranged from 96 to 177 µg/m³, and ambient PM₂.₅ reached 259 µg/m³. 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↗

PubMed2026

Long-term efficacy of cognitive behavioural therapy for insomnia (CBT-I) on depressive symptoms: A systematic review and meta-analysis of randomised controlled trials.

Depressive symptoms are common in individuals with persistent insomnia. Previous meta-analyses of randomised controlled trials (RCTs) showed that cognitive behavioural therapy for insomnia (CBT-I) can reduce depressive symptoms at post-treatment. However, the long-term maintenance of these improvements has never been systematically examined. To fill-in this gap, we conducted a systematic review and meta-analysis of the long-term (≥3 months) effects of CBT-I on depressive symptoms. The review was registered in PROSPERO (CRD420251146061). Only RCTs in adults with insomnia were considered. Pubmed, Scopus, Psycinfo, CINAHL, and Medline were searched up to 12 September 2025 with no predefined time constraints. From 5359 records initially retrieved, we included 53 articles reporting on 13,608 individuals. After outliers removal, random effects meta-analysis showed that CBT-I was superior to control conditions in reducing depressive symptoms at 3 [k = 29, d = -.35, [95% CI: -.49 to -.21], p < .001], 6 [k = 29, d = -.32, [95% CI: -.59 to -.05], p = .018], and 12 [k = 10, d = -.25, [95% CI: -.39 to -.12], p < .001] months follow-ups. Results demonstrate that the effects of CBT-I on depressive symptoms are sustained throughout the year following treatment, although effects may decline over time.

Humans↗

PubMed2026

Effects of exercise on aerobic capacity in people with prehypertension or hypertension: a systematic review and meta-analysis of randomized controlled trials.

This study aimed to quantify the effects of exercise on aerobic capacity in people with prehypertension or hypertension and to identify exercise prescription parameters that optimize improvements. A comprehensive search was conducted in PubMed, Web of Science, Embase, Cochrane Library, and Scopus from inception to 24 October 2025. Data were pooled using standardized mean differences (SMDs) with 95% confidence intervals (CI). Fifteen studies met the inclusion criteria. Exercise significantly improved aerobic capacity in people with prehypertension or hypertension (SMD = 0.88; 95% CI: 0.61-1.15; P  < 0.00001), with multicomponent training demonstrating superior efficacy. Exploratory subgroup analyses suggest that longer programs (≥12 weeks), lower frequency (<3 sessions/week), 60-min sessions or longer, total weekly exercise less than 180 min, and professional supervision may be associated with better outcomes.

Humans↗

PubMed2026

Impact of neoprene wetsuits on lung volumes and work of breathing: implications for military diver safety and performance.

INTRODUCTION: Neoprene wetsuits may impose mechanical constraints on the chest wall, potentially altering respiratory function. This study investigated the impact of neoprene wetsuits on lung volumes, airway mechanics, and work of breathing (WOB) in healthy male divers. METHODS: A randomised crossover trial was conducted with 31 male divers at the Royal Netherlands Navy Diving Medical Centre. Participants underwent pulmonary function testing, including spirometry, body plethysmography, the forced oscillation technique (FOT), and diffusion capacity measurements, both with and without a hoodless standardised 5 mm neoprene full body wetsuit with a neoprene neck seal. Primary outcomes included changes in forced vital capacity (FVC), functional residual capacity (FRC), airway resistance (Raw), reactance (Xrs), and WOB. RESULTS: Wearing a neoprene wetsuit led to statistically significant reductions in FVC (2.8%, P < 0.05), forced expiration in one second (2.9%, P < 0.05), FRC (4.0%, P < 0.05), and expiratory reserve volume (10.9%, P < 0.05), alongside increases in inspiratory capacity and tidal volume. Raw increased significantly (P < 0.05), while the FOT revealed altered airway mechanics, evidenced by increased Xrs at multiple frequencies (P < 0.05). Diffusion capacity remained unchanged, suggesting preserved alveolar-capillary function. CONCLUSIONS: Neoprene wetsuits induce mechanically restrictive effects on the chest wall, reducing static and dynamic lung volumes and increasing WOB. While these changes may not be clinically relevant at rest, their impact needs to be determined during strenuous or prolonged dives, particularly when combined with other equipment that limits thorax excursions. Future research should explore the effects of the military 5 mm wetsuit under immersed conditions to better understand their operational impact on diver performance and safety.

Male↗

PubMed2026

Effects of apple phenolics on the human metabolome: modulation of key metabolic pathways.

Apples are widely recognized for their potential health benefits, partly attributed to their phenolic compounds. However, their impact on human metabolism remains incompletely understood. This study investigated metabolic effects of apple-derived phenolic compounds using untargeted metabolomics approach across multiple biofluids. In a crossover intervention study, 30 healthy men consumed a phenolic-rich apple juice or a placebo for two weeks. Blood, urine and saliva samples were collected before and after each intervention and analyzed by direct infusion ultra-high resolution mass spectrometry. Consumption of apple phenolic compounds resulted in significant alterations of the human metabolome, including increased levels of phenolic-derived degradation products and microbial-associated metabolites across all biofluids. Pathway enrichment analysis revealed pronounced effects on phenylalanine and tyrosine metabolism, as well as linoleic and arachidonic acid metabolism, Overall, these findings demonstrate that apple phenolic compounds induce measurable, microbiota-associated and systemic metabolic changes, providing new insights into their metabolic fate and biological relevance.

Humans↗

PubMed2026

Insights from expert panels on the EU clinical evaluation consultation procedure.

BACKGROUND: The Clinical Evaluation Consultation Procedure (CECP) under the EU Medical Device Regulation aims to strengthen and harmonize the assessment of high-risk medical devices. This review summarizes early insights from expert panels to support improved clinical evaluation practices. RESEARCH DESIGN AND METHODS: This review analyses 34 expert panel opinions derived from 281 CECP submissions between April 2021 and December 2025. Statements from opinions were systematically extracted, de-duplicated, and grouped into thematic categories, with independent review and validation. The analysis focuses on common challenges found during the consultation procedure of the expert panels on the content of the clinical assessment in relation to clinical evidence, benefit-risk assessment, intended purpose alignment, and post-market clinical follow-up planning. RESULTS: Expert panel findings highlight recurrent issues in the sufficiency, consistency, and transparency of clinical evidence, underscoring the need for improved standardization and clearer guidance. CONCLUSIONS: Strengthening documentation quality and alignment across stakeholders will enhance the robustness, efficiency, and predictability of conformity assessments for high-risk medical devices.

Humans↗

PubMed2026

Non-destructive prediction of lead content in oilseed rape leaves by fluorescence hyperspectral technology based on neural network.

Based on fluorescence hyperspectral imaging (FHSI), this study targeted rapid, non-destructive quantification of lead (Pb) content in oilseed rape leaves treated with varying silicon (Si) concentrations, acquiring fluorescence spectra over the 484.43-1001.61 nm wavelength range. To optimize spectral data quality, preprocessing methods (Savitzky-Golay smoothing, first derivative, detrending) were comprehensively compared. Characteristic wavelengths were then selected via interval variable iterative shrinkage, which effectively compressed data dimensionality and reduced computational load. A hybrid SE-CL1DA model, fusing a 1D convolutional neural network, a long short-term memory network and SE attention mechanism was constructed, with Bayesian optimization tuning hyperparameters to boost stability. The BO-SE-CL1DA outperformed both traditional machine learning and insufficiently optimized deep learning model (Rp2=0.9609, RMSE = 0.0377 mg/kg, RPD = 5.1736), thus enabling accurate Pb estimation, supporting Si-regulated heavy metal stress management and facilitating agricultural contamination monitoring.

Plant Leaves↗

PubMed2026

In situ product monitoring in heterogeneous reaction of gaseous trimethylamine on Fe2O3/Fe(NO3)3: Effect of environmental factor and particle property.

Gas-particle reactions represent an important atmospheric heterogeneous transformation process for organic amines (OAs). Environmental factors and particle properties may impact the gas-particle reaction products. Although the products from gas-particle reactions can be monitored by various in situ techniques, related data remain scarce. Here, the interfacial and gaseous products from the reaction of trimethylamine on Fe2O3/Fe(NO3)3 particles under light irradiation with mixed NO2, O2, SO2 and H2O were monitored using in-situ diffuse reflectance Fourier transform infrared spectroscopy and proton transfer reaction time-of-flight mass spectrometry. Dark reaction of gaseous trimethylamine on Fe2O3/Fe(NO3)3 generated two interfacial products types: N-containing ones (CH3NCH2, CH3NO2, (CH3)2NCHO, and CH3N(OH)CHO) and N-free ones (alcohols, aldehydes and acids), both accumulating with reaction progression. Light irradiation and O2 oxidation enhanced formation of these products, while NO2 promoted the production of CH3NO2 and (CH3)2NCHO. H2O and SO2 occupied the active sites of particles to inhibit the formation of all products. Compared to Fe(NO3)3, Fe2O3 showed absolute dominance in contribution to the formation of products. Considering the smaller particle size of Fe2O3 and excess Fe(NO3)3, the physical mixing of them reduced the generation of interfacial products. Furthermore, gaseous products of CH3OH, HCHO, CH3CHO, HCOOH and CH3COOH detection clarified the N-free interfacial products. The presence of Fe(NO3)3 inhibited the formation of HCOOH and favored the formation of CH3CHO in the gas phase. By combining product information with thermodynamic calculations, the heterogeneous reaction pathways of trimethylamine were tentatively proposed. These findings provide a guiding significance for the migration of OAs in real atmospheric environment.

Methylamines↗