Inhibition of ER stress using tauroursodeoxycholic acid rescues obesity-evoked cardiac remodeling and contractile anomalies through regulation of ferroptosis.

Interrupted ER homeostasis contributes to the etiology of obesity cardiomyopathy although it remains elusive how ER stress evokes cardiac anomalies in obesity. Our study evaluated the impact of ER stress inhibition on cardiac anomalies in obesity. Lean and ob/ob obese mice received chemical ER chaperone tauroursodeoxycholic acid (TUDCA, 50 mg/kg/d, p.o.) for 35 days prior to evaluation of glucose sensitivity, echocardiographic, myocardial geometric, cardiomyocyte mechanical and subcellular Ca2+ property, mitochondrial integrity, oxidative stress, apoptosis, and ferroptosis. Intracellular Ca2+ governing domains including sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) were monitored by45Ca2+uptake and immunoblotting. Our results noted that TUDCA alleviated myocardial remodeling (fibrosis, hypertrophy, enlarged LVESD), echocardiographic anomalies (compromised fractional shortening and ejection fraction), cardiomyocyte contractile dysfunction (amplitude and velocity of cell shortening, relengthening time) and intracellular Ca2+ anomalies (compromised subcellular Ca2+ release, clearance and SERCA function), mitochondrial damage (collapsed membrane potential, downregulated mitochondrial elements and ultrastructural alteration), ER stress (GRP78, eIF2α and ATF4), oxidative stress, apoptosis and ferroptosis [downregulated SLC7A11, GPx4 and upregulated transferrin receptor (TFRC)] without affecting global glucose sensitivity and serum Fe2+ in obese mice. Obesity-evoked change in HSP90, phospholamban and Na+-Ca2+ exchanger was spared by the chemical ER chaperone. Moreover, in vitro results noted that TUDCA, PERK inhibitor GSK2606414, TFRC neutralizing antibody and ferroptosis inhibitor LIP1 mitigated palmitic acid-elicited changes in lipid peroxidation and mechanical function. Our findings favored a role for ferroptosis in obesity cardiomyopathy downstream of ER stress.

SCANeXt: Enhancing 3D medical image segmentation with dual attention network and depth-wise convolution.

Existing approaches to 3D medical image segmentation can be generally categorized into convolution-based or transformer-based methods. While convolutional neural networks (CNNs) demonstrate proficiency in extracting local features, they encounter challenges in capturing global representations. In contrast, the consecutive self-attention modules present in vision transformers excel at capturing long-range dependencies and achieving an expanded receptive field. In this paper, we propose a novel approach, termed SCANeXt, for 3D medical image segmentation. Our method combines the strengths of dual attention (Spatial and Channel Attention) and ConvNeXt to enhance representation learning for 3D medical images. In particular, we propose a novel self-attention mechanism crafted to encompass spatial and channel relationships throughout the entire feature dimension. To further extract multiscale features, we introduce a depth-wise convolution block inspired by ConvNeXt after the dual attention block. Extensive evaluations on three benchmark datasets, namely Synapse, BraTS, and ACDC, demonstrate the effectiveness of our proposed method in terms of accuracy. Our SCANeXt model achieves a state-of-the-art result with a Dice Similarity Score of 95.18% on the ACDC dataset, significantly outperforming current methods.

Electrochemical Phenyl-Carbonyl Coupling Reaction of Aromatic Aldehydes or Ketones.

An electrochemical phenyl-carbonyl coupling reaction of aromatic aldehydes or ketones to synthesize 4-(hydroxy(phenyl)methyl)benzaldehyde derivatives has been developed. The method shows high chemoselectivity, broad functional group compatibility, atom economy, and environmental benignity and has good potential applicability.

Regioselective Cycloaddition of Alkenes with tert-butyl Nitrite: A Cascade Approach to the Formation of Δ2-Isoxazolines.

A route for cycloaddition reaction of alkenes and tert-butyl nitrite to synthesize Δ2-isoxazolines has been developed. The overall process involves the formation of multiple chemical bonds without the use of a catalyst. This methodology features mild reaction conditions and good functional group tolerance, providing a direct approach for the preparation of isoxazolines.

Age at job initiation and risk of coronary heart disease: findings from the UK biobank cohort study.

BACKGROUND: Commencing work at an early age has been linked to various risk factors for coronary heart disease (CHD), such as shift work and intensive job strain. However, the relationship between starting work too early and CHD risk remains largely unclear. We examined the association between age at job initiation and the risk of CHD. METHODS: UK Biobank participants aged 38 to 70 years without cardiovascular disease who provided data on their age at job initiation were included. The primary outcome was CHD, which was ascertained using hospital and death records. The hazard ratios (HRs) and 95% confidence interval (CIs) for the association between age at job initiation and CHD were calculated using multivariable Cox regression. RESULTS: Of the 501,971 participants, 114,418 eligible participants were included in the final analysis. The median age at job initiation was 19.0 years. During the mean follow-up of 12.6 years, 6,130 (5.4%) first CHD events occurred. We observed that age at job initiation was inversely associated with CHD (HR 0.98, 95% CI 0.97-0.99), and the association was potentially J-shaped. The HRs for the < 17-year, 17-18-year, and 19-21-year age groups were 1.29 (95%CI 1.18-1.41), 1.12 (95% CI 1.03-1.22) and 1.05 (95% CI 0.97-1.14), respectively, compared with those of the ≥ 22-year group. CONCLUSIONS: Age at job initiation was associated with incident CHD, which was independent of socioeconomic status. Participants who commenced employment before the age of 19 years exhibited a higher risk of developing CHD later in adulthood.

Regional innovation effect of smart city construction in China.

Innovation is an important driving force for high-quality regional economic development. In recent years, the Chinese government has actively explored new ways to improve regional innovation level, and the construction of smart cities is regarded as an important measure to implement the innovation-driven development strategy. Based on the panel data of 287 prefecture-level cities in China from 2001 to 2019, this paper examined the impact of smart city construction on regional innovation. The research shows that: (i) The construction of smart city has significantly improved the level of regional innovation; (ii) Investment in science and technology and human capital level are important transmission paths for smart city construction to affect regional innovation; (iii) Compared with the central and western regions, the impact of smart city construction on regional innovation is more obvious in the eastern region. This study deepens the understanding of smart city construction, which has important policy significance for China to accelerate the construction of an innovative country and the healthy development of smart cities, and provides reference for other developing countries to promote smart city construction.

Predictors of in-hospital heart failure in patients with acute anterior wall ST-segment elevation myocardial infarction.

BACKGROUND: Heart failure (HF) is a severe complication of acute ST-segment elevation myocardial infarction (STEMI). Its incidence is associated with myocardial infarction location, and it occurs frequently after acute anterior wall STEMI due to the larger infarct size. However, predictors of in-hospital HF in patients with acute anterior wall STEMI are inadequately defined. We aimed to determine potential predictors of HF in patients with acute anterior wall STEMI during hospitalization. METHODS: A total of 714 consecutive patients who were diagnosed with acute anterior wall STEMI and underwent primary percutaneous coronary intervention (pPCI) between January 2013 to August 2019 were enrolled retrospectively. We assigned the patients to HF and non-HF groups. The clinical parameters were subjected to univariate analysis and logistic regression analysis to obtain the independent predictors. RESULTS: Among the 714 patients enrolled in the present study (mean age 61.0 ± 13.8 years, men 80.7%), 387 (54.2%) had in-hospital HF. According to a multivariate logistic regression analysis, ventricular fibrillation (VF, OR: 5.66, 95% CI: 2.25-14.23, P < 0.001) was the most striking independent predictor of in-hospital HF. Community-acquired pneumonia (CAP, OR: 4.72, 95% CI: 2.44-9.10, P < 0.001), age (OR: 1.03, 95% CI: 1.01-1.04, P < 0.001), left ventricular ejection fraction (LVEF, OR: 0.96, 95% CI: 0.93-0.97, P < 0.001), and peak N-terminal pro-brain natriuretic peptide (NT-pro-BNP, OR: 1.06, 95% CI: 1.02-1.11, P = 0.006) were also independently associated with in-hospital HF. CONCLUSION: VF, CAP, age, LVEF, and peak NT-pro-BNP were independently associated with in-hospital HF in patients with acute anterior wall STEMI.

Iron-Catalyzed Synthesis of Benzosultams from N-Phenyl-N-(prop-2-yn-1-yl)benzenesulfonamide and Benzenesulfonyl Hydrazine.

A novel route for an iron-catalyzed tandem sulfonylation, C(sp2)-H activation, cyclization reaction which uses N-phenyl-N-(prop-2-yn-1-yl)benzenesulfonamide and benzenesulfonohydrazide to synthesize derivatives of (Z)-2-phenyl-4-((phenylsulfonyl)methylene)-3,4-dihydro-2H-benzo[e][1,2]thiazine 1,1-dioxide has been developed. The method features convenient operation and good functional group tolerance. In addition, it employs insensitive and inexpensive FeSO4 as the catalyst and provides a direct approach for the preparation of benzothiazides.

Spatio-Temporal Point Process for Multiple Object Tracking.

Multiple object tracking (MOT) focuses on modeling the relationship of detected objects among consecutive frames and merge them into different trajectories. MOT remains a challenging task as noisy and confusing detection results often hinder the final performance. Furthermore, most existing research are focusing on improving detection algorithms and association strategies. As such, we propose a novel framework that can effectively predict and mask-out the noisy and confusing detection results before associating the objects into trajectories. In particular, we formulate such "bad" detection results as a sequence of events and adopt the spatio-temporal point process to model such events. Traditionally, the occurrence rate in a point process is characterized by an explicitly defined intensity function, which depends on the prior knowledge of some specific tasks. Thus, designing a proper model is expensive and time-consuming, with also limited ability to generalize well. To tackle this problem, we adopt the convolutional recurrent neural network (conv-RNN) to instantiate the point process, where its intensity function is automatically modeled by the training data. Furthermore, we show that our method captures both temporal and spatial evolution, which is essential in modeling events for MOT. Experimental results demonstrate notable improvements in addressing noisy and confusing detection results in MOT data sets. An improved state-of-the-art performance is achieved by incorporating our baseline MOT algorithm with the spatio-temporal point process model.

Thoracic perivascular adipose tissue inhibits VSMC apoptosis and aortic aneurysm formation in mice via the secretome of browning adipocytes.

Abdominal aortic aneurysm (AAA) is a dangerous vascular disease without any effective drug therapies so far. Emerging evidence suggests the phenotypic differences in perivascular adipose tissue (PVAT) between regions of the aorta are implicated in the development of atherosclerosis evidenced by the abdominal aorta more vulnerable to atherosclerosis than the thoracic aorta in large animals and humans. The prevalence of thoracic aortic aneurysms (TAA) is much less than that of abdominal aortic aneurysms (AAA). In this study we investigated the effect of thoracic PVAT (T-PVAT) transplantation on aortic aneurysm formation and the impact of T-PVAT on vascular smooth muscle cells. Calcium phosphate-induced mouse AAA model was established. T-PVAT (20 mg) was implanted around the abdominal aorta of recipient mice after removal of endogenous abdominal PVAT (A-PVAT) and calcium phosphate treatment. Mice were sacrificed two weeks after the surgery and the maximum external diameter of infrarenal aorta was measured. We found that T-PVAT displayed a more BAT-like phenotype than A-PVAT; transplantation of T-PVAT significantly attenuated calcium phosphate-induced abdominal aortic dilation and elastic degradation as compared to sham control or A-PVAT transplantation. In addition, T-PVAT transplantation largely preserved smooth muscle cell content in the abdominal aortic wall. Co-culture of T-PVAT with vascular smooth muscle cells (VSMCs) significantly inhibited H2O2- or TNFα plus cycloheximide-induced VSMC apoptosis. RNA sequencing analysis showed that T-PVAT was enriched by browning adipocytes and anti-apoptotic secretory proteins. We further verified that the secretome of mature adipocytes isolated from T-PVAT significantly inhibited H2O2- or TNFα plus cycloheximide-induced VSMC apoptosis. Using proteomic and bioinformatic analyses we identified cartilage oligomeric matrix protein (COMP) as a secreted protein significantly increased in T-PVAT. Recombinant COMP protein significantly inhibited VSMC apoptosis. We conclude that T-PVAT exerts anti-apoptosis effect on VSMCs and attenuates AAA formation, which is possibly attributed to the secretome of browning adipocytes.

Tandem Reduction, Ammonolysis, Condensation, and Deamination Reaction for Synthesis of Benzothiadiazines and 1-(Phenylsulfonyl)-1H-benzimidazoles.

A novel route for a SnCl2-promoted tandem reduction, ammonolysis, condensation, and deamination reaction which uses nitrile and 2-nitro-N-phenylbenzenesulfonamide/N-(2-nitrophenyl)benzenesulfonamide to synthesize derivatives of benzothiadiazine/1-(phenylsulfonyl)-1H-benzimidazole has been developed. The method features convenient operation and good functional group tolerance. In addition, it employs unsensitive and inexpensive SnCl2/i-PrOH as the reaction reagent and provides a direct approach for the synthesis of pharmaceutically important targets.

Colchicine Inhibits NETs and Alleviates Cardiac Remodeling after Acute Myocardial Infarction.

PURPOSE: Colchicine, a multipotent anti-inflammatory drug, has been reported to alleviate cardiac remodeling and improve cardiac function after acute myocardial infarction (AMI). However, the underlying mechanism remains incompletely understood. Because neutrophils extracellular traps (NETs) enhance inflammation and participate in myocardial ischemia injury, and colchicine can inhibit NETosis, we thus aimed to determine whether colchicine exerts cardioprotective effects on AMI via suppressing NETs. METHODS: Adult C57BL/6 mice were subjected to permanent ligation of the left anterior descending coronary artery and treated with colchicine (0.1 mg/kg/day) or Cl-amidine (10 mg/kg/day) for 7 or 28 days after AMI. Cardiac function was evaluated by echocardiography, and NETs detected by immunofluorescence. ROS production was detected using 2',7'-dichlorodihydrofluorescein diacetates (DCFH-DA) fluorometry. Intracellular Ca2+ concentration was assessed by a fluorometric ratio technique. RESULTS: We found that colchicine treatment significantly increased mice survival (89.8% in the colchicine group versus 67.9% in control, n = 32 per group; log-rank test, p < 0.05) and improved cardiac function at day 7 (left ventricular ejection fraction (LVEF): 28.0 ± 9.2% versus 12.6 ± 3.9%, n = 8 per group; p < 0.001) and at day 28 (LVEF: 26.2 ± 7.2% versus 14.8 ± 6.7%, n = 8 per group; p < 0.001) post-AMI. In addition, the administration of colchicine inhibited NETs formation and inflammation. Furthermore, colchicine inhibited NETs formation by reducing NOX2/ROS production and Ca2+ influx. Moreover, prevention of NETs formation with Cl-amidine significantly alleviated AMI-induced cardiac remodeling. CONCLUSIONS: Colchicine inhibited NETs and cardiac inflammation, and alleviated cardiac remodeling after acute myocardial infarction.

Inverse synthetic aperture ladar imaging based on modified cubic phase function.

Inverse synthetic aperture imaging ladar (ISAL) can achieve high-resolution images, and yet it faces pulse-to-pulse high-order phase errors that the microwave radar can ignore. The high-order phase errors are almost caused by mechanical vibrations in general, which blur the azimuth focusing effect. This paper presents an ISAL imaging model to obtain high-resolution images. A novel modified cubic phase function (CPF) algorithm is proposed to compensate the additional high-order phase errors. Some high-resolution well-focused ISAL simulation images and real target images are shown to validate the methods. It is shown that the third-order phase errors are compensated by the distinctive digital signal process and the image entropy of real target images is reduced significantly.

Pyridine Detection Using Supramolecular Organic Frameworks Incorporating Cucurbit[10]uril.

A physical impregnation method is presented in this study, providing a facile approach to encapsulating functional guest molecules (GMs) into robust crystalline supramolecular organic frameworks incorporating cucurbit[10]uril (Q[10]-SOF). As Q[10]-SOF has high evaporated pyridine affinity under normal atmospheric pressure, pyridine molecules in this method were successfully encapsulated into the nanospace formed by GMs and Q[10]-SOF while retaining their crystal framework, morphology, and high stability. GMs@Q[10]-SOF solid materials were found to respond to pyridine, being suitable to be used as solid sensors. Notably, Q[10]-SOF loading with pyrene exhibited a unique response to pyridine along with dramatic fluorescence quenching; loading with dansyl chloride exhibited a unique response to pyridine along with significant fluorescence enhancement, having a quick response within 60 s. Our findings represent a critical advancement in the design of pyridine detection and adsorption for commercial gas identification and sensing.

Estimation and correction of vibration-induced range cell migration for FMCW synthetic aperture ladar.

Synthetic aperture ladar (SAL) is a newly developed imaging device for remote sensing application. Owing to its short wavelength (3-5 orders of magnitude shorter than radar), SAL is very sensitive to platform vibration. For frequency-modulated continuous-wave SAL (FMCW-SAL), the platform vibration induces an additional range cell migration (RCM) to the SAL image. The vibration-induced RCM (VI-RCM) deteriorates the image quality. The VI-RCM is a unique problem for the FMCW-SAL imaging. To address this problem, a raw-data-driven method is proposed to correct the VI-RCM in this paper. First, the signal model was developed to show the VI-RCM in FMCW-SAL echo. Then, based on the model, the differential phase function (DPF) is constructed for the adjacent range profiles. The DPF is a single-frequency signal with its frequency being proportional to the relative range shift between the adjacent range profiles. Based on the DPF, the relative range shift is estimated. After the estimation of all the relative range shifts, the VI-RCM is calculated and corrected. Experiments are performed. The simulated experiment demonstrated the feasibility, accuracy, and efficiency of the proposed method, and the real data processing result verified the effectiveness of the proposed method for FMCW-SAL in practical applications.

Predictive risk factors of early onset left ventricular aneurysm formation in patients with acute ST-elevation myocardial infarction.

BACKGROUND: Left ventricular aneurysm (LVA) is a severe complication of ST-elevation myocardial infarction (STEMI) and is associated with poor prognosis due to high mortality. However, predictors of LVA formation in early period are inadequately defined. OBJECTIVES: The purpose of this study is to determine potential predictors of LVA formation in early period (<15 days after admission) after acute STEMI. METHODS: The present study was retrospectively conducted involving 1823 STEMI patients based on the AMI database of our clinic between January 2013 and April 2019. Among STEMI patients with regional wall motion abnormality (RWMA), the baseline, angiographic, procedural characteristics of patients with early-onset LVA and controls without LVA were compared. The controls were matched 2:1 with LVA cases for the admission date. Patients with prior myocardial infarction, non-ischemic cardiomyopathy, severe heart valve disease, and patients without coronary angiography were excluded. The odds ratio (OR) and confidence interval (CI) were obtained by logistic regression analysis and all statistical analysis were performed by SPSS 25.0. RESULTS: Among 1823 STEMI patients who underwent coronary angiography, 103 eligible patients (median age 67 years) had LVA and were compared to 206 patients without LVA (median age 60 years). In multivariate analysis, RWMA in the left ventricular anterior wall (OR 13.17, 95%CI 2.21-78.57, p=0.005) was found to be the most striking predictor of LVA, followed by RWMA in the apex (OR 7.93, 95%CI 2.22-28.30, p=0.001). Female sex (OR 3.91, 95%CI 1.54-9.93, p=0.004), peak N-terminal pro brain natriuretic peptide (NT-pro BNP,OR 1.08, 95%CI 1.01-1.16, p=0.031), time between onset of pain and balloon time (OR 1.01, 95%CI 1.00-1.01, P=0.016), and presence of QS-waves on initial electrocardiogram (OR 3.06, 95%CI 1.49-6.27, P=0.016) were independently associated with LVA formation. CONCLUSION: This study indicated that female sex, peak NT-pro BNP, the time between the onset of pain and balloon time, presence of QS-waves on initial electrocardiogram, RWMA of left ventricular anterior wall and apex were the independent predictors of early-onset LVA in patients with acute STEMI.

Layer-by-Layer Fabrication of Core-Shell Fe3O4@UiO-66-NH2 with High Catalytic Reactivity toward the Hydrolysis of Chemical Warfare Agent Simulants.

Detoxifying materials against chemical warfare agents (CWAs) and their simulants are highly desired for proper handling of contamination by and destruction of CWAs. Herein, we report a facile layer-by-layer fabrication of core-shell Fe3O4@UiO-66-NH2 and its application in fast degradation of CWA simulants. The Fe3O4@UiO-66-NH2 composite was prepared through a layer-by-layer epitaxial growth strategy, by alternately immersing Fe3O4 nanoparticles in ethanol solutions of a metal node [Zr6O4(OH)4]12+ precursor and organic linkers [NH2-BDC, 2-aminoterephthalic acid], respectively, and separating using a magnet. As confirmed by characterization results, the Fe3O4@UiO-66-NH2 composites with 24.4 µmol/g Zr6 node content showed a well-defined core-shell structure as well as good thermal and chemical stability. These core-shell magnetic metal-organic frameworks (MOFs) were further tested in the catalytic hydrolysis of dimethyl-4-nitrophenyl phosphate (a nerve agent simulant) and demonstrated 36 times higher catalytic activity than the UiO-66-NH2 powder due to their highly defective surface, high percentage of MOFs on the surface, and their rich mesoporous structure. Since magnetism was retained after the coating of MOFs, Fe3O4@UiO-66-NH2 could be easily recovered and reused after catalysis.

Combined Experimental and Molecular Simulation Investigation of the Individual Effects of Corexit Surfactants on the Aerosolization of Oil Spill Matter.

We report laboratory aerosolization experiments and classical molecular dynamics (MD) simulations, with the objective of investigating the individual effects of the two Corexit surfactants Span 80 (nonionic) and dioctyl sodium sulfosuccinate (DOSS, ionic), on the aerosolization of oil spill matter to the atmosphere. Our simulation results show that Span 80, DOSS, and the oil alkanes n-pentadecane (C15) and n-triacontane (C30) exhibit deep free energy minima at the air/seawater interface. C15 and C30 exhibit deeper free energy minima at the interface when Span 80 is present, as compared to the situation when DOSS or no surfactants are at the interface. These results suggest that Span 80 makes these oil hydrocarbons more likely to be adsorbed at the surface of seawater droplets and carried out to the atmosphere, relative to DOSS or to the situation where no surfactants are present. These simulation trends are in qualitative agreement with our experimental observations in a bubble-column setup, where larger amounts of oil hydrocarbons are ejected when Span 80 is mixed with oil and injected into the column, as compared to when DOSS is used. Our simulations also indicate that Span 80 has a larger thermodynamic incentive than DOSS to move from the seawater phase and into the air/seawater interface. This observation is also in qualitative agreement with our experimental measurements, which indicate that Span 80 is ejected in larger quantities than DOSS. Our simulations also suggest that DOSS predominantly adopts a perpendicular orientation with respect to the air/seawater interface at a dispersant to oil ratio (DOR) of 1:20, but has a slight preference to lie parallel to the interfaces at a DOR = 1:5; in both cases, DOSS molecules have their tails wide open and stretched. In contrast, Span 80 has a slight preference to align parallel to the interfaces with a coiled conformation at both DOR values.

Bubble bursting as an aerosol generation mechanism during an oil spill in the deep-sea environment: laboratory experimental demonstration of the transport pathway.

Oil spills in the deep-sea environment such as the 2010 Deep Water Horizon oil spill in the Gulf of Mexico release vast quantities of crude oil into the sea-surface environment. Various investigators have discussed the marine transport and fate of the oil into different environmental compartments (air, water, sediment, and biota). The transport of the oil into the atmosphere in these previous investigations has been limited to only evaporation, a volatility dependent pathway. In this work, we studied the aerosolization of oil spill matter via bursting bubbles as they occur during whitecaps in a laboratory aerosolization reactor. By evaluating the alkane content in oil mousse, crude oil, the gas phase, and particulate matter we clearly demonstrate that aerosolization via bursting bubbles is a solubility and volatility independent transport pathway for alkanes. The signature of alkane fractions in the native oil and aerosolized matter matched well especially for the less volatile alkanes (C20-C29). Scanning electron microscope interfaced with energy dispersive X-ray images identified the carbon fractions associated with salt particles of aerosols. Theoretical molecular dynamics simulations in the accompanying paper lend support to the observed propensity for alkanes at air-salt water interfaces of breaking bubbles and the produced droplets. The presence of a dispersant in the aqueous phase increased the oil ejection rate at the surface especially for the C20-C29 alkanes. The information presented here emphasizes the need to further study sea-spray aerosols as a possible transport vector for spilled oil in the sea surface environment.

Bubble bursting as an aerosol generation mechanism during an oil spill in the deep-sea environment: molecular dynamics simulations of oil alkanes and dispersants in atmospheric air/salt water interfaces.

Potential of mean force (PMF) calculations and molecular dynamics (MD) simulations were performed to investigate the properties of oil n-alkanes [i.e., n-pentadecane (C15), n-icosane (C20) and n-triacontane (C30)], as well as several surfactant species [i.e., the standard anionic surfactant sodium dodecyl sulfate (SDS), and three model dispersants similar to the Tween and Span species present in Corexit 9500A] at air/salt water interfaces. This study was motivated by the 2010 Deepwater Horizon (DWH) oil spill, and our simulation results show that, from the thermodynamic point of view, the n-alkanes and the model dispersants have a strong preference to remain at the air/salt water interface, as indicated by the presence of deep free energy minima at these interfaces. The free energy minimum of these n-alkanes becomes deeper as their chain length increases, and as the concentration of surfactant species at the interface increases. The n-alkanes tend to adopt a flat orientation and form aggregates at the bare air/salt water interface. When this interface is coated with surfactants, the n-alkanes tend to adopt more tilted orientations with respect to the vector normal to the interface. These simulation results are consistent with the experimental findings reported in the accompanying paper [Ehrenhauser et al., Environ. Sci.: Processes Impacts 2013, in press, (DOI: 10.1039/c3em00390f)]. The fact that these long-chain n-alkanes show a strong thermodynamic preference to remain at the air/salt water interfaces, especially if these interfaces are coated with surfactants, makes these species very likely to adsorb at the surface of bubbles or droplets and be ejected to the atmosphere by sea surface processes such as whitecaps (breaking waves) and bubble bursting. Finally, the experimental finding that more oil hydrocarbons are ejected when Corexit 9500A is present in the system is consistent with the deeper free energy minima observed for the n-alkanes at the air/salt water interface at increasing concentrations of surfactant species.