In-Scanner Thoughts shape Resting-state Functional Connectivity: how participants "rest" matters.

Resting-state fMRI (rs-fMRI) scans-namely those lacking experimentally-controlled stimuli or cognitive demands-are often used to identify aberrant patterns of functional connectivity (FC) in clinical populations. To minimize interpretational uncertainty, researchers control for across-cohort disparities in age, gender, co-morbidities, and head motion. Yet, studies rarely, if ever, consider the possibility that systematic differences in inner experience (i.e., what subjects think and feel during the scan) may directly affect FC measures. Here we demonstrate that is the case using a rs-fMRI dataset comprising 471 scans annotated with experiential data. Wide-spread significant differences in FC are observed between scans that systematically differ in terms of reported in-scanner experience. Additionally, we show that FC can successfully predict specific aspects of in-scanner experience in a manner similar to how it predicts demographics, cognitive abilities, clinical outcomes and labels. Together, these results highlight the key role of in-scanner experience in shaping rs-fMRI estimates of FC.

A Comparative Analysis of Two Commonly Used FDA-Approved Immunoassays for Fentanyl Detection.

BACKGROUND: Given the opioid epidemic, fentanyl screening in urine has become increasingly important. Immunoassays remain the most common screening methodology due to the high throughput and ease of integration into automated chemistry systems. The fentanyl ARK II from Ark Diagnostics is a widely used immunoassay, while a novel fentanyl assay called FEN2 by Lin-Zhi has become available on the Roche platform. Here, we evaluate and compare their performance. METHODS: Four hundred and thirty-four urine samples were analyzed for fentanyl across the Lin-Zhi FEN2 and ARK II assays on the Cobas c502 platform. Samples were analyzed immediately upon request for drug of abuse screening or frozen for subsequent analysis. For confirmation testing, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method with a limit of detection of 1 ng/mL for fentanyl/norfentanyl was used. Any sample with either fentanyl or norfentanyl above the LC-MS/MS cutoff was deemed positive. RESULTS: The ARK II had 11 false negatives and 7 false positives, while the Lin-Zhi FEN2 had 12 false negatives and 2 false positives. This resulted in ARK II having a sensitivity and specificity of 90.4% and 97.8% respectively, while Lin-Zhi FEN2 had a sensitivity and specificity of 89.5% and 99.4%. CONCLUSIONS: Both the ARK II and Lin-Zhi FEN2 immunoassays detected fentanyl well. Overall, the Lin-Zhi assay had slightly better specificity than ARK II, in our data set. While some discrepant results were observed between the 2 immunoassay systems, most occurred near the immunoassay detection cutoffs.

Brief Report: Risk of Recurrent Interstitial Lung Disease From Osimertinib Versus Erlotinib Rechallenge After Symptomatic Osimertinib-Induced Interstitial Lung Disease.

Introduction: Interstitial lung disease (ILD) is the most frequent cause of drug-related mortality from EGFR tyrosine kinase inhibitors (TKIs). Yet, for patients with symptomatic osimertinib-induced ILD, the risk of recurrent ILD associated with EGFR TKI rechallenge, either with osimertinib or another TKI, such as erlotinib, is unclear. Methods: Retrospective study of 913 patients who received osimertinib treatment for EGFR mutation-positive NSCLC. Clinical characteristics, ILD treatment history, and subsequent anticancer therapy of patients with symptomatic osimertinib-induced ILD were collated. The primary end point was to compare the incidence of recurrent ILD with osimertinib versus erlotinib rechallenge. Results: Of 913 patients, 35 (3.8%) had symptomatic osimertinib-induced ILD, of which 12 (34%), 15 (43%), and eight (23%) had grade 2, 3 to 4, and 5 ILD, respectively. On ILD recovery, 17 patients had EGFR TKI rechallenge with eight received osimertinib and nine received erlotinib. The risk of recurrent ILD was higher with osimertinib rechallenge than erlotinib (p = 0.0498). Of eight, five (63%) developed recurrent ILD on osimertinib rechallenge, including three patients with fatal outcomes. In contrast, only one of nine patients (11%) treated with erlotinib had recurrent ILD. Median time to second ILD occurrence was 4.7 (range 0.7-12) weeks. Median time-to-treatment failure of patients with erlotinib rechallenge was 13.2 months (95% confidence interval: 8.6-15.0). Conclusions: The risk of recurrent ILD was considerably higher with osimertinib rechallenge than erlotinib. Osimertinib rechallenge should be avoided, whereas erlotinib may be considered in patients with symptomatic osimertinib-induced ILD.

In vitro biological evaluation and in silico studies of linear diarylheptanoids from Curcuma aromatica Salisb. as urease inhibitors.

Plants of the Zingiberaceae family, specifically those belonging to the Curcuma species, are commonly under consideration as potential therapeutic agents for the management of gastrointestinal diseases. In this study, we carried out a phytochemical study on Curcuma aromatica Salisb. (or so-called "Nghe trang" in Vietnamese) grown in Vietnam, which yields three newly discovered 3,5-diacetoxy diarylheptanoids (1-3) and six known 3,5-dihydroxyl diarylheptanoids (4-9). The bioactivity assessment shows that all isolated compounds, except compounds 3, 7, and 8, could inhibit urease. Compounds 4 and 9 significantly inhibit urease, with an IC50 value of 9.6 and 21.4 µM, respectively, more substantial than the positive control, hydroxyurea (IC50 = 77.4 µM). The structure-activity relationship (SAR) of linear diarylheptanoids was also established, suggesting that the hydroxyl groups at any position of skeleton diarylheptanoids are essential for exerting anti-urease action. Through a comparative analysis of the binding sites of hydroxyurea and diarylheptanoid compounds via our constructed in silico model, the mechanism of action of diarylheptanoid compounds is predicted to bind to the dynamic region close to the dinickel active center, resulting in a loss of catalytic activity. Such insights certainly help design and/or find diarylheptanoid-based compounds for treating gastric ulcers through inhibiting urease.

Estimation of trajectory of protective efficacy in infectious disease prevention trials using recurrent event times.

In studies of infectious disease prevention, the level of protective efficacy of medicinal products such as vaccines and prophylactic drugs tends to vary over time. Many products require administration of multiple doses at scheduled times, as opposed to one-off or continual intervention. Accurate information on the trajectory of the level of protective efficacy over time facilitates informed clinical recommendations and implementation strategies, for example, with respect to the timing of administration of the doses. Based on concepts from pharmacokinetic and pharmacodynamic modeling, we propose a non-linear function for modeling the trajectory after each dose. The cumulative effect of multiple doses of the products is captured by an additive series of the function. The model has the advantages of parsimony and interpretability, while remaining flexible in capturing features of the trajectories. We incorporate this series into the Andersen-Gill model for analysis of recurrent event time data and compare it with alternative parametric and non-parametric functions. We use data on clinical malaria disease episodes from a trial of four doses of an anti-malarial drug combination for chemoprevention to illustrate, and evaluate the performance of the methods using simulation. The proposed method out-performed the alternatives in the analysis of real data in terms of Akaike and Bayesian Information Criterion. It also accurately captured the features of the protective efficacy trajectory such as the area under curve in simulations. The proposed method has strong potential to enhance the evaluation of disease prevention measures and improve their implementation strategies.

Validated assays for the quantification of C9orf72 human pathology.

A repeat expansion mutation in the C9orf72 gene is the leading known genetic cause of FTD and ALS. The C9orf72-ALS/FTD field has been plagued by a lack of reliable tools to monitor this genomic locus and its RNA and protein products. We have validated assays that quantify C9orf72 pathobiology at the DNA, RNA and protein levels using knock-out human iPSC lines as controls. Here we show that single-molecule sequencing can accurately measure the repeat expansion and faithfully report on changes to the C9orf72 locus in what has been a traditionally hard to sequence genomic region. This is of particular value to sizing and phasing the repeat expansion and determining changes to the gene locus after gene editing. We developed ddPCR assays to quantify two major C9orf72 transcript variants, which we validated by selective excision of their distinct transcriptional start sites. Using validated knock-out human iPSC lines, we validated 4 commercially available antibodies (of 9 tested) that were specific for C9orf72 protein quantification by Western blot, but none were specific for immunocytochemistry. We tested 15 combinations of antibodies against dipeptide repeat proteins (DPRs) across 66 concentrations using MSD immunoassay, and found two (against poly-GA and poly-GP) that yielded a 1.5-fold or greater signal increase in patient iPSC-motor neurons compared to knock-out control, and validated them in human postmortem and transgenic mouse brain tissue. Our validated DNA, RNA and protein assays are applicable to discovery research as well as clinical trials.

Urban green waste bulking agent is the major source of antimicrobial resistance genes persisted in home compost, not animal manure.

Urban green waste and food waste are often used as bulking agents to prepare home compost in combination with animal manure in urban horticulture and community gardening. Although it is known that antimicrobial resistance genes (ARGs) persist in home compost, their origins have not been determined. In addition, the factors contributing to ARGs persistence remain unclear. In this study, we aim to (i) characterize the changes in the microbiome and antimicrobial resistome during the composting process of home compost using metagenomics shotgun sequencing, (ii) identify the source of the ARGs persisted in home compost using SourceTracker, and (iii) elucidate the collective effect of compost microbiome and environmental factors, including the physicochemical properties and antibiotics concentration of home compost, in contributing to ARG persistence using Procrustes analysis, co-occurrence network analysis, variation partitioning analysis, and structural equation modeling. SourceTracker analysis indicated that urban green waste bulking agent was the major source of the persisting ARGs in home compost instead of animal manure. Procrustes analysis and co-occurrence network analysis revealed a strong association between microbiome and antimicrobial resistome. Variation partitioning analysis and structural equation modeling suggested that physicochemical properties shaped the antimicrobial resistome directly and indirectly by influencing the microbiome. Our results indicated that the persistence of ARGs in home compost might be due to the succession of microbial species from the urban green waste bulking agent, and the physicochemical properties might have defined the compost environment to shape the microbiome in the compost, thus, in turn, the persisting antimicrobial resistome.

Performance of large language models at the MRCS Part A: a tool for medical education?

INTRODUCTION: The Intercollegiate Membership of the Royal College of Surgeons examination (MRCS) Part A assesses generic surgical sciences and applied knowledge using 300 multiple-choice Single Best Answer items. Large Language Models (LLMs) are trained on vast amounts of text to generate natural language outputs, and applications in healthcare and medical education are rising. METHODS: Two LLMs, ChatGPT (OpenAI) and Bard (Google AI), were tested using 300 questions from a popular MRCS Part A question bank without/with need for justification (NJ/J). LLM outputs were scored according to accuracy, concordance and insight. RESULTS: ChatGPT achieved 85.7%/84.3% accuracy for NJ/J encodings. Bard achieved 64%/64.3% accuracy for NJ/J encodings. ChatGPT and Bard displayed high levels of concordance for NJ (95.3%; 81.7%) and J (93.7%; 79.7%) encodings, respectively. ChatGPT and Bard provided an insightful statement in >98% and >86% outputs, respectively. DISCUSSION: This study demonstrates that ChatGPT achieves passing-level accuracy at MRCS Part A, and both LLMs achieve high concordance and provide insightful responses to test questions. Instances of clinically inappropriate or inaccurate decision-making, incomplete appreciation of nuanced clinical scenarios and utilisation of out-of-date guidance was, however, noted. LLMs are accessible and time-efficient tools, access vast clinical knowledge, and may reduce the emphasis on factual recall in medical education and assessment. CONCLUSION: ChatGPT achieves passing-level accuracy for MRCS Part A with concordant and insightful outputs. Future applications of LLMs in healthcare must be cautious of hallucinations and incorrect reasoning but have the potential to develop AI-supported clinicians.

Ab initio kinetics of the CH3NH + NO2 reaction: formation of nitramines and N-alkyl nitroxides.

This study provides a detailed understanding of how the reaction between CH3NH, one of the primary products of the CH3NH2 + OH/Cl reactions, and NOx occurs in the atmosphere since the reaction is expected to be a dominant sink for the tropospheric CH3NH radical. First, we focus on the reaction of the aminyl radical CH3NH with NO2, complementing the known reaction between CH3NH and NO, to provide the overall picture of the CH3NH + NOx system. The reaction was meticulously examined across the extended range of temperature (298-2000 K) and pressure (0.76-76 000 torr) using quantum chemistry calculations and kinetic modeling based on the framework of the Rice-Ramsperger-Kassel-Marcus (RRKM)-based master equation. Highly correlated electronic structure calculations unveil that the intricate reaction mechanism of the CH3NH + NO2 reaction, which can proceed through O-addition or N-addition to form NO2, encompasses numerous steps, channels, and various intermediates and products. The temperature-/pressure-dependent kinetic behaviors and product distribution of the CH3NH + NO2 reaction are revealed under atmospheric and combustion conditions. The main products under atmospheric conditions are found to be CH3NHO and NO, as well as CH3NHNO2, while under combustion conditions, the primary products are only CH3NHO and NO. Given its stability under ambient conditions, CH3NHNO2, a nitramine, is believed to have the potential to induce DNA damage, which can ultimately result in severe cancers. Secondly, by building upon prior research on the CH3NH + NO system, this study shows that the reaction of CH3NH with NOx holds greater importance in urban areas with elevated NOx emissions than other oxidants like O2. Furthermore, this reaction occurs swiftly and results in the creation of various compounds, such as the carcinogenic nitrosamine (CH3NHNO), carcinogenic nitramine (CH3NHNO2), CH3NNOH, (CH3NN + H2O) and (CH3NHO + NO).

Identification of potential anti-hyperglycemic compounds in Cordyceps militaris ethyl acetate extract: in vitro and in silico studies.

Cordyceps militaris has been long known for valuable health benefits by folk experience and was recently reported with diabetes-tackling evidences, thus deserving extending efforts on screening for component-activity relationship. In this study, experiments were carried out to find the evidence, justification, and input for computations on the potential against diabetes-related protein structures: PDB-4W93, PDB-3W37, and PDB-4A3A. Liquid chromatography identified 14 bioactive compounds in the ethyl acetate extract (1-14) and quantified the contents of cordycepin (0.11%) and adenosine (0.01%). Bioassays revealed the overall potential of the extract against α-amylase (IC50 = 6.443 ± 0.364 mg.mL-1) and α-glucosidase (IC50 = 2.580 ± 0.194 mg.mL-1). A combination of different computational platforms was used to select the most promising candidates for applications as anti-diabetic bio-inhibitors, i.e. 1 (ground state: -888.49715 a.u.; dipole moment 3.779 Debye; DS¯ -12.3 kcal.mol-1; polarizability 34.7 Å3; logP - 1.30), 10 (ground state: -688.52406 a.u.; dipole moment 5.487 Debye; DS¯ -12.6 kcal.mol-1; polarizability 24.9 Å3; logP - 3.39), and 12 (ground state: -1460.07276 a.u.; dipole moment 3.976 Debye; DS¯ -12.5 kcal.mol-1; polarizability 52.4 Å3; logP - 4.39). The results encourage further experimental tests on cordycepin (1), mannitol (10), and adenosylribose (12) to validate their in-practice diabetes-related activities, thus conducive to hypoglycemic applications.Communicated by Ramaswamy H. Sarma.

Mechanistic and Kinetic Insights into OH-Initiated Atmospheric Oxidation of Hymexazol: A Computational Study.

Hymexazol is a volatile fungicide widely used in agriculture, causing its abundance in the atmosphere; thus, its atmospheric fate and conversion are of great importance when assessing its environmental impacts. Herein, we report a theoretical kinetic mechanism for the oxidation of hymexazol by OH radicals, as well as the subsequent reactions of its main products with O2 and then with NO by using the Rice-Ramsperger-Kassel-Marcus-based Master equation kinetic model on the potential energy surface explored at the ROCBS-QB3//M06-2X/aug-cc-pVTZ level. The predicted total rate constants ktotal(T, P) for the reaction between hymexazol and OH radicals show excellent agreement with scarcely available experimental values (e.g., 3.6 × 10-12 vs (4.4 ± 0.8) × 10-12 cm3/molecule/s at T = 300 K and P = 760 Torr); thus, the calculated kinetic parameters can be confidently used for modeling/simulation of N-heterocycle-related applications under atmospheric and even combustion conditions. The model shows that 3,4-dihydroxy-5-methyl-4,5-dihydro-1,2-oxazol-5-yl (IM2), 3,5-dihydroxy-5-methyl-4,5-dihydro-1,2-oxazol-4-yl (IM3), and (3-hydroxy-1,2-oxazol-5-yl)methyl (P8) are the main primary intermediates, which form the main secondary species of (3,4-dihydroxy-5-methyl-4,5-dihydro-1,2-oxazol-5-yl)dioxidanyl (IM4), (3,5-dihydroxy-5-methyl-4,5-dihydro-1,2-oxazol-4-yl)dioxidanyl (IM7), and ([(3-hydroxy-1,2-oxazol-5-yl)methyl]dioxidanyl (IM11), respectively, through the reactions with O2. The main secondary species then can react with NO to form the main tertiary species, namely, (3,4-dihydroxy-5-methyl-4,5-dihydro-1,2-oxazol-5-yl)oxidanyl (P19), (3,5-dihydroxy-5-methyl-4,5-dihydro-1,2-oxazol-4-yl)oxidanyl (P21), and [(3-hydroxy-1,2-oxazol-5-yl)methyl]oxidanyl (P23), respectively, together with NO2. Besides, hymexazol could be a persistent organic pollutant in the troposphere due to its calculated half-life τ1/2 of 13.7-68.1 h, depending on the altitude.

Risks and impacts of thromboembolism in patients with pancreatic cancer.

INTRODUCTION: Patients with pancreatic cancer have a high risk of thromboembolism (TE), which may increase mortality. Most relevant studies have been conducted in Western populations. We investigated risk factors for TE in a predominantly Chinese population of patients with pancreatic cancer, along with effects of TE on overall survival. METHODS: This retrospective cohort study included patients diagnosed with exocrine pancreatic cancer in Prince of Wales Hospital in Hong Kong between 2010 and 2015. Data regarding patient demographics, World Health Organization performance status, stage, treatment, TE-related information, and time of death (if applicable) were retrieved from electronic medical records. Univariate and multivariable logistic regression analyses were performed to identify risk factors for TE. Survival analyses were performed using Kaplan-Meier analysis and Cox proportional hazards regression. RESULTS: In total, 365 patients were included in the study. The overall incidence of TE (14.8%) was lower than in Western populations. In univariate logistic regression analysis, stage IV disease and non-head pancreatic cancer were significantly associated with TE (both P=0.01). Multivariable logistic regression analysis showed that stage IV disease was a significant risk factor (odds ratio=1.08, 95% confidence interval [CI]=1.00-1.17; P=0.046). Median overall survival did not significantly differ between patients with and without TE (4.88 months vs 7.80 months, hazard ratio=1.08, 95% CI=0.80-1.49; P=0.58) and between patients with TE who received anticoagulation treatment or not (5.63 months vs 4.77 months, hazard ratio=0.72, 95% CI=0.40-1.29; P=0.27). CONCLUSION: The incidence of TE was low in our Chinese cohort. Stage IV disease increased the risk of TE. Overall survival was not affected by TE or its treatment.

A case of false positive opiate immunoassay results from rifampin (rifampicin) treatment.

The drug screen test on a 12-year-old male patient was positive for opiates by a kinetic interaction of microparticles in solution (KIMS) immunoassay method on the Roche Cobas C502. The positive opiates result was not confirmed by the liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. A chart review revealed that the patient had tuberculosis and was on rifampin. We spiked rifampin into drug-free urine and tested opiates with the Cobas method. Once again, a positive result was obtained. This case showed that rifampin can still cause false positive opiate results measured with the KIMS method. We want to stress the importance of confirming positive screen results by more specific methods such as LC-MS/MS.

HAVOC: Small-scale histomic mapping of cancer biodiversity across large tissue distances using deep neural networks.

Intratumoral heterogeneity can wreak havoc on current precision medicine strategies because of challenges in sufficient sampling of geographically separated areas of biodiversity distributed across centimeter-scale tumor distances. To address this gap, we developed a deep learning pipeline that leverages histomorphologic fingerprints of tissue to create "Histomic Atlases of Variation Of Cancers" (HAVOC). Using a number of objective molecular readouts, we demonstrate that HAVOC can define regional cancer boundaries with distinct biology. Using larger tumor specimens, we show that HAVOC can map biodiversity even across multiple tissue sections. By guiding profiling of 19 partitions across six high-grade gliomas, HAVOC revealed that distinct differentiation states can often coexist and be regionally distributed within these tumors. Last, to highlight generalizability, we benchmark HAVOC on additional tumor types. Together, we establish HAVOC as a versatile tool to generate small-scale maps of tissue heterogeneity and guide regional deployment of molecular resources to relevant biodiverse niches.

Opportunities and challenges of tackling Scope 3 "Indirect" emissions from residential hot water.

The water sector could play a major role towards a Net Zero greenhouse gas (GHG) future if Scope 3 emissions were embraced and operationalised. Significant opportunities and challenges exist in tackling Scope 3 emissions including those associated with customer hot water use. Present GHG emission reduction practices predominantly focus on Scope 1 "within utility" and Scope 2 "purchased energy" emissions. In the urban water cycle, Scope 3 "indirect" emissions dominate, and water use is only one example of Scope 3 emissions. Over 90% of all water cycle GHG emissions can be attributed to water use in residential, industrial and commercial premises, collectively some 7% of global GHG emissions. One possibility is for water utilities to actively support efficient hot water use such as new ultra-low flow shower heads. Scope 3 opportunities also offer a range of cost-effective emissions-reduction opportunities, particularly when the wider perspective of "community value" is considered and not just a "business financial perspective". Hot water efficiency is additionally essential to Net Zero carbon futures, even with decarbonised grids, because most major Net Zero roadmaps require energy efficiency gains. Scientific and management advance needed includes: accounting methodologies, clear roles, collaboration, new business models, and clear definitions. The water sector has the opportunity to play a significant role in achieving Net Zero cities. The decision how much is yet to be made.

Social operant conditioning of autobiographical memory sharing.

The memories for past autobiographical experiences that we share can influence relationship formation and consolidation with important implications for our mental health. However, little is known about how people's responses to our memories can influence subsequent memory sharing. Previous research examined how operant processes (i.e., punishment with aversive sounds) influence the sharing of memories for specific events from our past. Understanding the (social) mechanisms associated with difficulty sharing specific autobiographical memories is important given the association between these difficulties and a range of psychiatric diagnoses. We investigate the effects of verbal and non-verbal social operants on the willingness to share specific autobiographical memories. Participants shared memories with a confederate who coded their memories as specific or non-specific and responded in either an engaged/attentive, dismissive manner or gave no feedback depending on participants' assigned condition. Participants who were reinforced for sharing specific memories and punished for sharing non-specific memories, were more likely to share specific than non-specific memories compared to those who received no feedback. Reinforcement alone was not sufficient for modifying specificity. The ways that we respond to people when they share memories with us can influence their subsequent willingness to share specific events from their past.

The interplay of membrane fluidity, acyl chain order and area per lipid on the partitioning of two antidepressants paroxetine and sertraline.

Selective serotonin reuptake inhibitors (SSRIs) are among the popular drugs for treating depression and mental disorders. Membrane fluidity has previously been considered as the main factor in modulating the membrane partitioning of SSRIs, while other biophysical properties, such as the acyl chain order and area per lipid, were often neglected. Varying the lipid membrane composition and temperature can significantly modify the physical phase and, in turn, affect its fluidity, acyl chain order and area per lipid. Here, we investigate the role of membrane fluidity, acyl chain order and area per lipid in the partitioning of two SSRIs, paroxetine (PAX) and sertraline (SER). The model membranes were either POPC : SM (1 : 1 mol ratio) or POPC : SM : Chol (1 : 1 : 1 mol ratio) and studied in the temperature range of 25-45 °C. The order parameters and area per lipid in the two lipid mixtures were calculated using molecular dynamics simulations. The membrane partitioning of PAX and SER was determined via second derivative spectrophotometry. In a lower temperature range (25-32 °C), membrane fluidity favors the SSRI partitioning into Lo/Ld POPC:SM:Chol. In a higher temperature range (37-45 °C), the interplay between membrane fluidity, acyl chain order and area per lipid favors drug partitioning into Ld POPC:SM. The findings offer indication for the inconsistent distribution of SSRIs in tissues as well as the possible interaction of SSRIs with lipid domains and membrane-bound proteins.

OH-initiated oxidation of vinyl butyrate: ab initio insights.

The widespread use of vinyl butyrate (CH2CHOC(O)CH2CH2CH3 or VB) in the polymer industry and daily-life materials inevitably results in its emission into the atmosphere. Therefore, understanding the mechanism and kinetics of the VB conversion is critical for evaluating its fate and environmental impacts. Herein, we theoretically investigate the chemical transformation of VB initiated by OH radicals in the atmosphere using the stochastic Rice-Ramsperger-Kassel-Marcus (RRKM)-based master equation kinetic model on the potential energy surface explored at the M06-2X/aug-cc-pVTZ level of theory. Showing excellent agreement with limited experimental kinetic data, the VB + OH kinetic model reveals that H-abstraction from Cß (i.e., -CßH2CH3) prevails over the OH-addition to the double bond (CC), even at low temperatures. The detailed analyses, including those of the time-resolved species profiles, reaction rate, and reaction flux, reveal the reaction mechanism shift with temperature (causing the U-shaped temperature dependence of k(T, P)) and the noticeable pressure dependence of k(T, P) at low temperatures. The secondary chemistry under atmospheric conditions (namely, the reaction of the main product with O2 and its subsequent reactions with NO) was then characterized within the same framework to reveal the detailed kinetic mechanism (e.g., [4-(ethenyloxy)-4-oxobutan-2-yl]oxidanyl (IM12) + NO2 is the dominant channel under atmospheric conditions), suggesting VB is not a persistent organic pollutant and a new environmental concern regarding the formed NO2. Also, the kinetic behaviors of vinyl butyrate and its oxidation products were extended from atmospheric to combustion conditions for further applications. Moreover, through TD-DFT calculations, it is shown that several related important species (i.e., 1-(ethenyloxy)-1-oxobutan-2-yl (P4), [4-(ethenyloxy)-4-oxobutan-2-yl]dioxidanyl (IM7), and IM12) can potentially undergo photolysis in the atmosphere.