Search

The affordances of social media, have significantly transformed how patients seek and process health information online, including those with chronic diseases like irritable bowel disease (IBD). Few studies have explored how information processing may impact symptom management. Guided by social cognitive theory, this study investigates how Chinese and U.S. patients (N = 838) process health information in a cross-cultural setting and the impact on symptom management. It finds that efficient information processing improves treatment understanding and symptom management for IBD patients, regardless of their cultural backgrounds. It also reveals a U-shaped quadratic relationship between IBD severity and emotional and peer support, indicating varying support needs at different IBD stages. These findings provide valuable insights for healthcare professionals, patients, and caregivers in designing interventions for chronic diseases. The study underscores the importance of recognizing the dynamics of health information processing and the need for a more nuanced approach to patient support and care. [ABSTRACT FROM AUTHOR]

Several vascular embolization materials are commonly used in clinical practice, however, having application defects of varying degrees, such as poor intraoperative imaging and easy recanalization of embolized blood vessels, they are challenging for application during Transcatheter arterial embolization (TAE). Thus, an intraoperative visible vascular embolization material with good embolization effect and biocompatibility can improve transcatheter arterial embolization clinical efficacy to some extent. Our study aimed to synthesize a novel vascular embolization material that can achieve complete embolization of arterial trunks and peripheral vessels, namely poly (N-isopropyl acrylamide)-co-acrylic acid nanogel (NIPAM-co-AA). Iohexol 200 mg/mL was co-assembled with 7 wt% NIPAM-co-AA nanogel to create an intelligent thermosensitive radiopaque nanogel (INCA), which achieves a good intraoperative imaging effect and is convenient for transcatheter arterial bolus injection due to its good fluidity and temperature-sensitive sol-gel phase transition. The normal rabbit kidney embolism model further confirmed that INCA could effectively use Digital subtraction angiography (DSA) to achieve intraoperative imaging, and real-time monitoring of the embolization process could avoid mis-embolization and leakage. Meanwhile, in a 42-day study, INCA demonstrated an excellent embolization effect on the right renal artery of New Zealand white rabbits, with no vascular recanalization and ischemic necrosis and calcification remaining. As a result, this radiopaque thermosensitive nanogel has the potential to be an intelligent thermosensitive medical vascular embolization material, providing dual benefits in TAE intraoperative imaging and long-term postoperative embolization while effectively addressing the shortcomings and challenges of commonly used clinical vascular embolization agents. [ABSTRACT FROM AUTHOR]

A surge in interest surrounding metasurfaces has been witnessed in recent years, driven by their capability to autonomously manipulate electromagnetic wavefront (EM) in three-dimensional space. While the initial focus in metasurface research has often been on manipulating electromagnetic waves using single polarization and frequency schemes, significant advancements have been made to overcome these limitations. Recent developments have introduced multifunctional metasurfaces that enable simultaneous control over multiple frequencies and polarizations, substantially enhancing their capacity for information processing and communication. Building on these advancements, our work introduces a novel three-channel full-space metasurface that leverages double-face copper-cladded patterns on a single-layer substrate, significantly increasing channel capacity through both frequency and polarization multiplexing. In order to achieve efficient control of the EM wavefront in multi-frequency and polarization scenarios, a super unit cell-based approach is utilized, wherein high-performance meta-atoms are combined to form super unit cells with minimal interferences. Specifically, different functionalities can be achieved in full space under different wave polarizations and frequencies. To validate the concept, a metasurface sample is fabricated and experimentally tested. The experimental results agree with both theoretical predictions and simulations, confirming the effectiveness of a three-channel metasurface holography. The metasurface achieves independent control of the incident EM wave's polarization and frequency, thus enhancing information storage capacity and encryption security. • A metasurface for three-channel holographic imaging using polarization-frequency multiplexing is proposed. • The design uses super unit cells for efficient EM wave phase control. • Two holographic images are achieved under LP wave illumination using the propagation phase principle. • A holographic image is achieved under LCP illumination using the geometric phase principle in the transmission semi-space. • Simulations and experiments confirm independent control of polarization and frequency, enhancing storage and security. [ABSTRACT FROM AUTHOR]

Stochastic optimization acceleration is extremely significant and challenging for deep neural networks (DNNs). In recent years, several novel proportional-integral–differential-based (PID-based) optimizers have been proposed to speed up the optimization by alleviating the oscillation behavior of stochastic gradient descent with momentum (SGD-M), yet lacked theoretical analysis. Along this line of research, this paper adopts dynamical system theory to design a new hybrid optimizer and present theoretical analysis. Firstly, it is found that DNN optimization is equivalent to a discrete time dynamical system. Building upon the equivalence, high order augmented dynamical system viewpoint is utilized to design a PI-like optimizer for ensuring high accuracy, which is more stable than SGD-M. Then, hybrid dynamical system viewpoint is employed to improve the PI-like optimizer as a new hybrid form for suppressing oscillation and accelerating optimization. Lyapunov method, Taylor series, matrix theory and equilibrium are combined to theoretically investigate the convergence and the oscillation of loss function, showing that the proposed hybrid optimizer can alleviate oscillation, boost optimization speed, and maintain high accuracy. In theoretical analyses, explicit conditions of hyper-parameters that guarantee training stability are calculated and presented, practically guiding the adjustment of hyper-parameters and promoting the application of hybrid optimizer. Experiments are presented on three commonly used benchmark datasets, i.e., MNIST, CIFAR10 and CIFAR100, demonstrating that the hybrid optimizer obtains up to 42% acceleration with competitive accuracy relative to state-of-the-art optimizers. In short, this paper not only presents a new hybrid optimizer for accelerating optimization, but also provides a novel, theoretical and systematic perspective to find and analyze new optimizer for DNNs. [ABSTRACT FROM AUTHOR]

There is an on-going demand in recent years for safer and "greener" hair coloring agents with the global consumer awareness of the adverse effects of synthetic hair dyes. The belief in sustainability and health benefits has focused the attention of the scientific community towards natural colorants that serve to replace their synthetic toxic counterparts. This review article encompasses the historical applications of a vast array of natural plant hair dyes and summarizes the possible coloration mechanisms (direct dyeing and mordant dyeing). Current information on phytochemicals (quinones, tannins, flavonoids, indigo, curcuminoids and carotenoids) used for hair dyeing are summarized, including their botanical sources, color chemistry and biological/toxicological activities. A particular focus is given on research into new natural hair dye sources along with eco-friendly, robust and cost-effective technologies for their processing and applications, such as the synthetic biology approach for colorant production, encapsulation techniques for stabilization and the development of inorganic nanocarriers. In addition, innovative in vitro approaches for the toxicological assessments of natural hair dye cosmetics are highlighted. [ABSTRACT FROM AUTHOR]

This paper presents a unified least-squares approach to simultaneous input and state estimation (SISE) of discrete-time linear systems. Although input estimators for systems with and without direct feedthrough are generally designed in two different ways, i.e., one with and another without a delay, the proposed approach unifies the two cases using a receding horizon estimation strategy. Moreover, regularization terms representing input information are incorporated and discarded to accommodate the model-based and model-free scenarios, respectively. The present work first investigates the general case where prior input information is available for systems with direct feedthrough and addresses important issues including the existence, optimality and stability of the derived estimators. Then, the problem of whether and under what conditions the existing studies for different systems can be related together is investigated. By setting different design parameters, the proposed estimation framework includes important literature results as its special cases, making it possible to generalize the SISE problems in various contexts. Besides, unlike the previous studies that only considered recursive SISE formulations, the present study develops a batch SISE (BSISE) formulation that addresses the optimal filtering and smoothing problems cohesively. The present work provides a unified approach to input and state estimation where the availability of the input information ranges from exactly known to completely unknown and the systems may have either zero, non-full-rank or full-rank direct feedthrough. The optimization-based formulation and its Bayesian interpretation open a variety of possible extensions and inspire new developments. [ABSTRACT FROM AUTHOR]

This paper investigates the leaderless consensus control problem of high-order nonholonomic chained systems. Based on the relationship between state and consensus error, a novel Lyapunov function is defined and is proved positive definite and radially unbounded. The first control law is constructed to make the Lyapunov function non-increasing. The Lyapunov method, graph theory and LaSalle invariance principle are applied to analyse system stability, where some skillful mathematical calculations are conducted to overcome the difficulties caused by nonholonomic constraint and high-order structure, and the explicit expression and the conditions of control parameter matrix are calculated. Then, the second control law is designed by extending the results to the input saturation case. Both of the two controllers are smooth, time-invariant, static, distributed, and able to achieve global asymptotic consensus of nonholonomic chained systems over connected undirected graph. Numerical simulation examples are implemented to demonstrate the effectiveness of the proposed control schemes. [ABSTRACT FROM AUTHOR]

Necroptosis is a type of regulated cell death (RCD) that is triggered by changes in the extracellular or intracellular milieu that are picked up by certain death receptors. Thanks to its potent capacity to induce immunological responses and overcome apoptotic resistance, it has garnered significant attention as a potential cancer treatment. Basic information for the creation of nano-biomedical treatments is provided by studies on the mechanisms underlying tumor necroptosis. Receptor-interacting protein kinase 1 (RIPK1)–RIPK3-mediated necroptosis, Toll-like receptor domain-containing adapter-inducing interferon (IFN)-β (TRIF)–RIPK3-mediated necroptosis, Z-DNA-binding protein 1 (ZBP1)–RIPK3-mediated necroptosis, and IFNR-mediated necroptosis are the four signaling pathways that collectively account for triggered necroptosis in this review. Necroptosis has garnered significant interest as a possible cancer treatment strategy because, in contrast to apoptosis, it elicits immunological responses that are relevant to therapy. Thus, a thorough discussion is held on the connections between tumor cell necroptosis and the immune environment, cancer immunosurveillance, and cells such as dendritic cells (DCs), cytotoxic T cells, natural killer (NK) cells, natural killer T (NKT) cells, and their respective cytokines. Lastly, a summary of the most recent nanomedicines that cause necroptosis in order to cause immunogenic cell death is provided in order to emphasize their promise for cancer immunotherapy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Exciton dynamics includes exciton generation, diffusion, dissociation and recombination. • Recent research progress of exciton dynamics in photo(electro)catalysis is overviewed. • Characterization techniques of exciton dynamics in photo(electro)catalysis are summarized. • Modulating strategies of exciton dynamics in photo(electro)catalysis are discussed. • Conclusions and outlooks of exciton dynamics in photo(electro)catalysis are presented. The fundamental study on photo(electro)catalytic reactions is central for the potential application in solving energy and environmental issues. However, the exciton effect, which affects their photo(electro)catalytic performance especially in organic and low-dimensional inorganic materials, is less explored. Therefore, it is necessary to investigate the exciton dynamics involved in the photo(electro)catalytic process, and the strategies for modulating exciton dynamics are also needed for improving the photo(electro)catalytic performance. In this review, we introduce the exciton dynamics and main exciton characterization techniques, and summarize the mechanisms for modulating exciton dynamics in photo(electro)catalysis. Finally, current challenges and future possible developments for exciton dynamics in the photo(electro)catalytic process are discussed. We hope this review will provide insights on the exciton dynamics in the photo(electro)catalysis, thus inspiring more researches on the materials with strong exciton effect in photo(electro)catalytic applications. [ABSTRACT FROM AUTHOR]

Background. Osteoporosis is a major disease that affects the quality of life of middle-aged and old people, so it is very important to find efficient and safe drugs to treat osteoporosis. The purpose of this study was to investigate the therapeutic effect of naringin on postmenopausal osteoporosis in ovariectomized (OVX) rats. Methods. Chinese biomedical databases, CNKI, PubMed, EMBASE, and Wan Fang were searched for articles from inception to March 2020. Two independent researchers screened articles according to inclusion criteria. RevMan 5.3 was used for data analysis. Results. Ten studies were included in the systematic review. The bone mineral density (BMD) significantly increased after naringin treatment (weighted mean difference, 0.06; 95% CI, 0.03–0.09; P < 0.01). There was no significant increase in BMD after estrogen treatment compared with naringin (weighted mean difference, 0.00; 95% CI, −0.00 to 0.01; P = 0.06). The trabecular bone volume (BV/TV) (weighted mean difference, 2.09; 95% CI, 1.85–2.34; P < 0.01) and trabecular thickness (Tb.Th) (weighted mean difference, 6.65; 95% CI, 6.55–6.74; P < 0.01) significantly increased after using naringin. Conclusions. Naringin had been shown to promote bone formation in OVX rats. However, the mechanism of naringin needs more research to confirm. [ABSTRACT FROM AUTHOR]

This study aims to enhance the stability and bioavailability of astaxanthin by loading it into nanostructured lipid carriers (NLCs), then incorporating the NLCs into alginate microgels. The NLCs (about 200 nm particle size) and alginate microgels (about 1 mm particle size) are prepared using high‐pressure homogenization and injection‐gelation methods, respectively. Based on in vitro dissolution assessments, the astaxanthin in alginate microgels dissolves more slowly than that in NLCs. In simulated gastric digestive juice, minimal dissolution of microgel‐embedded astaxanthin is detected; however, in simulated intestinal digestive juice, the dissolution is appreciably accelerated. Moreover, the 2 h bio‐accessibility of astaxanthin in microgels is less than that in NLCs. At higher concentrations of sodium alginate and calcium ions, the internal pores of the microgels become smaller, resulting in slower dissolution and lower bio‐accessibility of astaxanthin. As for the chemical stability of the pigment, it is improved by the secondary coating effect of hydrogelation. Hence, NLC incorporation into alginate microgels constitutes a promising strategy for the encapsulation of astaxanthin in the food industry. Practical applications : Nanostructured lipid carriers (NLCs) incorporated in alginate microgels can increase the water solubility of astaxanthin, improve its chemical stability, increase its bioavailability, and allow for its controlled release. The high‐pressure homogenization method used to prepare NLCs can be easily applied on an industrial level. Moreover, the operation conditions of the injection‐gelation process needed to synthesize the alginate microgels are mild, nontoxic, and nonpolluting. The NLC‐alginate microgels can be used in yogurt, ice cream, and other foods. [ABSTRACT FROM AUTHOR]

Size‐fractionated aerosol particles were collected with a MOUDI 10‐stage cascade impactor from an urban roadside place in a downtown area of Hong Kong. Fine aerosol particulate samples from stage 6 (aerodynamic particle diameter between 0.56 and 1 μm) and stage 9 (aerodynamic particle diameter between 0.10 and 0.18 μm) were pretreated at a chosen temperature, including −100°C, −50°C, 25°C, and 60°C, in a load lock chamber and then analyzed using time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) at the same temperature (−100°C). Principal component analysis (PCA) was applied to further analyze ToF‐SIMS spectra of aerosol particles with different pretreatment temperatures from two selected stages. ToF‐SIMS results showed that the intensities of aliphatic hydrocarbon ions such as C4H7+ and C4H9+ and amine ions such as C2H8N+ and C4H12N+ decreased with an increase of the pretreatment temperature under ultrahigh vacuum conditions. We have shown that analyses of this type of aerosol particles using ToF‐SIMS should not be conducted at ambient temperature but at low temperature (eg, −50°C). In addition, we also developed a procedure that can be used to analyze aerosol particle samples under ultrahigh vacuum environment. [ABSTRACT FROM AUTHOR]

Previous research has revealed the privacy paradox, which suggests that despite concern about their online privacy, people still reveal a large amount of personal information and don't take measures to protect personal privacy online. Using data from a national-wide survey, this study takes a psychological approach and uses the rational fatalism theory to explain the privacy paradox on the Internet and the social networking sites (SNSs). The rational fatalism theory argues that risks will become rational if the person believes he or she has no control over the outcome. Our results support the rational fatalism view. We found that people with higher levels of fatalistic belief about technologies and business are less likely to protect their privacy on the Internet in general, and the SNS in particular. Moreover, such relationship is stronger among young Internet users compared with older users. [ABSTRACT FROM AUTHOR]

Bioelectrochemical systems (BESs) are an innovative technology for the efficient degradation of antibiotics. Shewanella oneidensis (S. oneidensis) MR-1 plays a pivotal role in degrading sulfamethoxazole (SMX) in BESs. Our study investigated the effect of BES conditions on SMX degradation, focusing on microbial activity. The results revealed that BESs operating with a 0.05 M electrolyte concentration and 2 mA/cm2 current density outperformed electrolysis cells (ECs). Additionally, higher electrolyte concentrations and elevated current density reduced SMX degradation efficiency. The presence of nutrients had minimal effect on the growth of S. oneidensis MR-1 in BESs; it indicates that S. oneidensis MR-1 can degrade SMX without nutrients in a short period of time. We also highlighted the significance of mass transfer between the cathode and anode. Limiting mass transfer at a 10 cm electrode distance enhanced S. oneidensis MR-1 activity and BES performance. In summary, this study reveals the complex interaction of factors affecting the efficiency of BES degradation of antibiotics and provides support for environmental pollution control. [ABSTRACT FROM AUTHOR]

Polystyrene (PS)‐dioctyl phthalate (DOP) films were prepared by spin coating solutions of a mixture of PS and DOP on Si wafers and characterized by time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) and X‐ray photoelectron spectroscopy (XPS). ToF‐SIMS depth profile results showed that DOP mainly segregated to the top 10 nm of the surface of the PS‐DOP film as well as to the interface between the film and the substrate. The normalized intensities of the ions corresponding to DOP on the surface increased as the annealing temperature increased and reached a maximum at the annealing temperature of 60°C, and then decreased as the annealing temperature increased. XPS results indicate that the maximum amount of DOP segregated to the top surface of the PS‐DOP film can reach to 39 wt% at the annealing temperature of 60°C. In addition, DOP evaporated at 25°C under ultra‐high vacuum conditions; hence, ToF‐SIMS and XPS analyses need to be carried out at low temperatures (e.g., −40°C). [ABSTRACT FROM AUTHOR]

The calcination temperature has a great influence on the adsorption performance, but there are few studies on the calcination temperature. In this research, the effects on clinoptilolite calcined at different temperatures under vacuum conditions are studied and the raw material of clinoptilolite comes from China's Liaoning Province. Clinoptilolite treated at 100 °C is methane selectivity and the equilibrium adsorption capacity between methane and nitrogen at 1 atm (atmosphere) pressure reaches 5.73. With the increase of treatment temperature, the adsorption capacities of methane and nitrogen on clinoptilolite increase, but the influence of changing calcination temperature on nitrogen adsorption is more significant. After calcination at 150 °C, clinoptilolite gradually changes to nitrogen selectivity, and the nitrogen selectivity reaches the maximum at 190 °C. The ratio of equilibrium adsorption capacity between nitrogen and methane at 1 atm (atmosphere) pressure is 1.52. When the calcination temperature reaches 350 °C, clinoptilolite can’t be regenerated after adsorption performance. The adsorption capacity of nitrogen on clinoptilolite calcined at 190 °C at 100 s (second) reaches 0.32 mmol/g, while the adsorption of methane at this time is only 0.032 mmol/g, so the nitrogen kinetic selectivity of clinoptilolite calcined at 190 °C is much greater than that of methane. [ABSTRACT FROM AUTHOR]

Defects were created on the surface of highly oriented pyrolytic graphite (HOPG) by sputtering with an Ar+ ion beam, then characterized using X‐ray photoelectron spectroscopy (XPS) and time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) at 500°C. In the XPS C1s spectrum of the sputtered HOPG, a sp3 carbon peak appeared at 285.3 eV, representing surface defects. In addition, 2 sets of peaks, the Cx− and CxH− ion series (where x = 1, 2, 3...), were identified in the ToF‐SIMS negative ion spectrum. In the positive ion spectrum, a series of CxH2+• ions indicating defects was observed. Annealing of the sputtered samples under Ar was conducted at different temperatures. The XPS and ToF‐SIMS spectra of the sputtered HOPG after 800°C annealing were observed to be similar to the spectra of the fresh HOPG. The sp3 carbon peak had disappeared from the C1s spectrum, and the normalized intensities of the CxH− and CxH2+• ions had decreased. These results indicate that defects created by sputtering on the surface of HOPG can be repaired by high‐temperature annealing. [ABSTRACT FROM AUTHOR]

This work investigates a new formation control problem of multiple underactuated surface vessels. The controller design is based on input-output linearisation technique, graph theory, consensus idea and some nonlinear tools. The proposed smooth time-varying distributed control law guarantees that the multiple underactuated surface vessels globally exponentially converge to some desired geometric shape, which is especially centred at the initial average position of vessels. Furthermore, the stability analysis of zero dynamics proves that the orientations of vessels tend to some constants that are dependent on the initial values of vessels, and the velocities and control inputs of the vessels decay to zero. All the results are obtained under the communication scenarios of static directed balanced graph with a spanning tree. Effectiveness of the proposed distributed control scheme is demonstrated using a simulation example. [ABSTRACT FROM AUTHOR]

Global asymptotic stabilization of underactuated surface vessels is generally achieved only by designing complicated controllers. This paper proposes a very simple control law that globally asymptotically stabilizes the position of underactuated surface vessel to a desired constant location and its velocities to zero. The proposed controller is independent of velocity signals and is robust to model parameters. It neither includes an observer nor an adaptive/sliding-mode law. Controller development and stability analysis rely on a novel Lyapunov function and LaSalle's theorem. Furthermore, by extending the proposed control strategy, a saturated control law is also obtained ensuring the semiglobal asymptotic stability of position error system. Effectiveness of the proposed control schemes is demonstrated by simulation examples. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Whether political ties enhance or weaken firm performance has been widely investigated in a number of studies, including some on China. Based on a database of non-financial A-share listed firms from 2004 to 2012, we study the effects of political ties on firm performance within a quantile regression framework. We find that there is a positive relationship between political ties and economic performance, but that it is diminishing with respect to firm performance. Political ties appear particularly important for weaker firms. [ABSTRACT FROM PUBLISHER]

Clean surface of graphene was obtained at 500 °C and characterized by X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). In the XPS C1s spectrum of graphene, besides an asymmetric sp 2 carbon peak and a π-π ∗ shake-up peak appeared, an additional sp 3 carbon peak representing sp 3 defects was also present. In the ToF-SIMS positive ion spectrum of graphene, a series of C x H 2 + ions originated from the defects of graphene was found. To determine the origin of the C x H 2 + ions, defects were created on the surface of nearly defect-free highly oriented pyrolytic graphite (HOPG) by bombarding it with a Cs + ion beam at various sputtering doses. A detailed examination of the positive ion spectra of ion-bombarded HOPG surfaces reveals the presence of the C x H 2 + ions, confirming that these C x H 2 + ions, which came from the defects created on the sputtered HOPG surfaces, are similar to the defects present on graphene surface. A sp 3 carbon peak at 285.3 eV, representing sp 3 defects appeared in the XPS spectra of sputtered HOPG samples, confirms that the surface of the sputtered HOPG is similar to that of graphene. Fragmentation mechanisms of selected ions in the ToF-SIMS spectra of graphene and HOPG were proposed. [ABSTRACT FROM AUTHOR]

The concept of crash precursor identification is gaining more practicality due to the recent advancements in Advanced Transportation Management and Information Systems. Investigating the shortcomings of the existing models, this paper proposes a new method to model the real time crash likelihood based on loop data through schematic eigenvectors. Firstly, traffic volume, occupancy and density spatiotemporal schematics in certain duration before an accident occurrence were constructed to describe the traffic flow status. Secondly, eigenvectors and eigenvalues of the spatiotemporal schematics were extracted to represent traffic volume, occupancy and density situation before the crash occurrence. Thirdly, by setting the vectors in crash time as case and those at crash free time as control, a logistic model is constructed to identify the crash precursors. Results show that both the eigenvectors and eigenvalues can significantly impact the accident likelihood compared to the previous study, the proposed model has the advantage of avoiding multicollinearity, better reflection of the overall traffic flow status before the crash, and improving missing data problem of loop detectors. [ABSTRACT FROM AUTHOR]

Secondary traffic accidents are generally recorded without being specifically noted as such in the accident database, leading to difficulty in the study of such accidents. Previous research generally classified secondary incidents by predefining fixed spatio-temporal boundaries—a method that can be very subjective. Using 10,762 accident records gathered from 2012 upstream loop detector data on a California interstate freeway, this paper proposes a dynamic method for more convincing and accurate classification based on traffic shock waves detected by the loop detectors. This method identifies and associates a secondary accident with its primary accident if it is tested and found to have occurred within the spatio-temporal impact area of the primary accident. Shock waves from each accident are calculated and updated along freeway via multiple detectors, and secondary accidents are identified as those that occur within the spatio-temporal boundaries of a primary accident. Results show that secondary accidents account for 1.08% of California interstate freeway accidents, which is much lower than previous research estimates. Dispersed spatio-temporal gaps between primary and secondary accident pairs were found with an expectation of 71.09 min and 3.88 miles with a standard deviation of 55.36 min and 4.64 miles respectively. [ABSTRACT FROM AUTHOR]

The cleanliness of the surface of graphene is important for its proper functioning in devices and sensors. Impurities including residual poly(methyl methacrylate) (PMMA) and hydrocarbon contaminants can alter its electronic and chemical properties. In this study, we used two surface-sensitive techniques, X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS), to monitor the chemical composition of the surface of graphene after washing it with acetone and annealing at high temperatures. The concentration of residual PMMA and hydrocarbon contaminants decreased as the annealing temperature increased. The atomic ratio of sp 3 carbons to sp 2 carbons of a clean graphene surface determined using XPS can be used to estimate the amounts of sp 3 defects in graphene. ToF-SIMS spectra indicate that residual PMMA was removed from the surface of graphene at 400 °C, while hydrocarbon contaminants required a higher temperature of 500 °C to remove. In ToF-SIMS spectra obtained at 500 °C, the characteristic ions for graphene, which are related to cleavage of ring structure, include C x + ( x = 1, 2, 3…), C x H + and C x H 2 + as well as C x − and C x H − . For the first time, we developed a process to produce a very clean graphene surface which was verified by ToF-SIMS and XPS analyses. [ABSTRACT FROM AUTHOR]

Self-disclosure is popular on social network site (SNS). However, teenagers’ self-disclosure behavior and their regret of posting, a negative emotional experience, have been seldom studied. Using data from a nationally representative survey, this study tries to investigate teenagers’ self-disclosure and regret of posting on SNS. We further examine how demographic variables, SNS use, different types of “friends”, trust, and privacy control behavior relate to self-disclosure and regret of posting. We find that though teenagers reveal moderately high level of personal information on SNS, they do not disclose all types of personal information equally. Results also show that male and older teens disclose more personal information. Frequent SNS use, large SNS network size, and having strangers in SNS friend list increase both self-disclosure and posting regret. Setting SNS profile private is related to lower level of self-disclosure. Implications for privacy design of SNS are discussed. [ABSTRACT FROM AUTHOR]

The full-state stabilization scheme is proposed for the control of an underactuated surface vessel with unknown modeling parameters. By knowing only the upper/lower bounds of model parameters, the designed controller is the first one able to globally uniformly asymptotically stabilize all the states of the vessel to zero. The virtual surge velocity control law is first derived, which makes the Lyapunov function at the kinematic level non-increasing, irrelevant to the yaw velocity, leaving a freedom for choosing the virtual yaw velocity control law to stabilize the other state variables. After finishing the design of virtual velocity law, the back-stepping approach and the Lyapunov redesign technique are combined to obtain the actual force/torque control law despite parameter uncertainties. Simulation examples are given to illustrate the effectiveness of the proposed control law, showing that all the states and the control inputs are globally uniformly asymptotically convergent to zero under parameter uncertainties and are globally bounded under unknown external bounded disturbances. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Adopting a longitudinal angle, this study analyzed data from the Pew Internet's Health Tracking Survey in 2006, 2008, and 2010 to identify potential communication inequalities in social networking site use. Results showed that with the growing role of social networking site use in predicting people's likelihood of seeking health information online, the socioeconomic and demographic factors that contributed to the disparities in social networking site use could also lead to disparities in seeking health information online. Also, results indicated that people are more likely to seek heath-related information online if they or their close family or friends have a chronic disease situation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sepiolite and palygorskite are an abundant natural 1D nanofibrous clay mineral. • They are increasingly used in the dermopharmaceutical and cosmetic fields. • Their dosage forms for topical application and toxicological aspects were reviewed. • Applications include pelotherapy, wound healing, antimicrobial, coloration and UV protection. Functionalization of natural clay minerals for high value-added pharmaceutical and cosmetic applications receives significant research attention worldwide attributable to a rising demand and ongoing search for green, efficient, economically sustainable and ecofriendly geomaterials. Fibrous clays, i.e. palygorskite and sepiolite, are naturally-occurring hydrated magnesium aluminum silicate clay minerals with 2:1 layer-chain microstructure and one-dimensional nanofibrous morphology. Due to their unique structural, textural and compatibility features, over the past decade, fibrous clays and their organic modified derivatives are increasingly used in the dermopharmaceutical and cosmetic fields as excipients, active agents or nanocarriers to develop novel skin delivery systems or to modify drug release profile for enhanced health effects. This comprehensive review presents the up-to-date information on fibrous clays used in topically-applied products for therapeutic and cosmetic purposes with the focus on their performance-related structural characteristics and the underlying mechanisms. The recent advancement of fibrous clay-based skin delivery systems was summarized in wide range of applications including pelotherapy, wound healing, antimicrobial action, coloration and UV protection. An overview of the commonly used topically-applied dosage forms (powders, hydrogels, films, peloids and Pickering emulsion) as well as the toxicological aspects was also included, which might provide guidance to the design and development of fibrous clay-based skin delivery systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sepiolite and palygorskite are an abundant natural 1D nanofibrous clay mineral. • They are increasingly used in the dermopharmaceutical and cosmetic fields. • Their dosage forms for topical application and toxicological aspects were reviewed. • Applications include pelotherapy, wound healing, antimicrobial, coloration and UV protection. Functionalization of natural clay minerals for high value-added pharmaceutical and cosmetic applications receives significant research attention worldwide attributable to a rising demand and ongoing search for green, efficient, economically sustainable and ecofriendly geomaterials. Fibrous clays, i.e. palygorskite and sepiolite, are naturally-occurring hydrated magnesium aluminum silicate clay minerals with 2:1 layer-chain microstructure and one-dimensional nanofibrous morphology. Due to their unique structural, textural and compatibility features, over the past decade, fibrous clays and their organic modified derivatives are increasingly used in the dermopharmaceutical and cosmetic fields as excipients, active agents or nanocarriers to develop novel skin delivery systems or to modify drug release profile for enhanced health effects. This comprehensive review presents the up-to-date information on fibrous clays used in topically-applied products for therapeutic and cosmetic purposes with the focus on their performance-related structural characteristics and the underlying mechanisms. The recent advancement of fibrous clay-based skin delivery systems was summarized in wide range of applications including pelotherapy, wound healing, antimicrobial action, coloration and UV protection. An overview of the commonly used topically-applied dosage forms (powders, hydrogels, films, peloids and Pickering emulsion) as well as the toxicological aspects was also included, which might provide guidance to the design and development of fibrous clay-based skin delivery systems. [ABSTRACT FROM AUTHOR]

Social network sites (SNSs) and mobile phones are becoming increasingly important in teenagers’ lives. Using data collected from a nationally representative survey ( N = 800), this study explores the variation of social capital by SNS adoption, different SNS activities, and mobile personal talk among teenagers. The results indicate that SNS adoption and mobile personal talk can not only enhance teenagers’ close ties with friends, but also jointly promote teenagers’ civic engagement. Among SNS users, mobile personal talk also increase teens’ network capital. Different SNS activities such as commenting on friend’s Facebook pictures and joining Facebook groups have different relationships with social capital, and such relationships are moderated by mobile personal talk. [ABSTRACT FROM AUTHOR]

This work investigates the position centroid rendezvous/formation problems of multiple unicycle agents for the first time. By constructing a new output, the unicycle model is converted to canonical normal form via feedback linearisation approach. Then, we propose the centroid rendezvous and the centroid formation control laws, respectively, guaranteeing that all the agents globally meet at the common initial centroid location and the desired geometric pattern centred at the initial centroid. The proposed control laws are distributed, smooth and time‐varying, ensuring the internal orientation states and the velocity inputs convergent to some fixed values and zero, respectively. All the results are proved under the communication scenarios of fixed directed balanced graph with a spanning tree. Simulation results verify the effectiveness and the robustness of the proposed control schemes. [ABSTRACT FROM AUTHOR]

This experiment investigates effects of communication interface proximity, which was conceptualized as three different media platforms (desktop, laptop, and hand-held device), on college students’ anxiety when receiving emergency alerts about on-campus crimes via emails and text messages. It proposes a new dimension of proximity, interface proximity, and suggests a shift in the emphasis of proximity from audience to event to user to interface. Ninety seven students received alerts on one of the three devices for 2 days. User anxiety increased for news-like information such as crime alerts and varied according to the proximity of the media platform. A three-level model of anxiety, including trait anxiety, media exposure to negative compelling news, and a trigger event, all contributed to participants’ anxiety. [ABSTRACT FROM PUBLISHER]

Highlights: [•] Two socialization agents can influence teens’ online privacy concern. [•] Parents and social networking sites are the two socialization agents. [•] Increasing teens’ online privacy concern will enhance privacy-setting strategies. [•] Increasing teens’ online privacy concern will decrease Facebook profile visibility. [Copyright &y& Elsevier]

Abstract: A novel cathode, Pd loaded Ti/TiO2 nanotubes (Pd–Ti/TiO2NTs), is synthesized for the electrocatalytic reduction of trichloroethylene (TCE) in groundwater. Pd nanoparticles are successfully loaded on TiO2 nanotubes which grow on Ti plate via anodization. Using Pd–Ti/TiO2NTs as the cathode in an undivided electrolytic cell, TCE is efficiently and quantitatively transformed to ethane. Under conditions of 100 mA and pH 7, the removal efficiency of TCE (21 mg/L) is up to 91% within 120 min, following pseudo-first-order kinetics with the rate constant of 0.019 min−1. Reduction rates increase from 0.007 to 0.019 min−1 with increasing the current from 20 to 100 mA, slightly decrease in the presence of 10 mM chloride or bicarbonate, and decline with increasing the concentrations of sulfite or sulfide. O2 generated at the anode slightly influences TCE reduction. At low currents, TCE is mainly reduced by direct electron transfer on the Pd–Ti/TiO2NT cathode. However, the contribution of Pd-catalytic hydrodechlorination, an indirect reduction mechanism, becomes significant with increasing the current. Compared with other common cathodes, i.e., Ti-based mixed metal oxides, graphite and Pd/Ti, Pd–Ti/TiO2NTs cathode shows superior performance for TCE reduction. [Copyright &y& Elsevier]

Sulfur and nitrogen-doped carbon dots (SN-CDs) were prepared by the solvothermal method with PET waste, sulfuric acid, and phenylenediamine as precursors. The as-prepared SN-CDs were characterized by TEM, XPS, FTIR, NMR, and fluorescence spectrometer, and their applications in light-blocking membranes (LBFs) were explored. The results show that SN-CDs are spherical structures with an average particle size of 4.3 nm, and there are sulfur-containing and nitrogen-containing groups on their surface. The fluorescence emission peak for SN-CDs is dependent on the excitation wavelength in the range from 320 to 500 nm. When the excitation wavelength is 420 nm, the emission peak for SN-CDs is located at 540 nm, and the fluorescence intensity is the highest. The fluorescence quantum yield can reach 49.36%, and the average fluorescence lifetime is 6.28 ns. In terms of application, the as-prepared SN-CDs could be dispersed in polylactic acid (PLA) matrix to prepare light-blocking film (LBFs) for UV and blue light. When the amount of SN-CDs is 7%, the blocking rate of LBFs for 365 nm ultraviolet light is close to 100%, and the blocking rate for 430 nm blue light is as high as 90%. As a result, its ability to block light from mobile phone screens and the sun is better than that of commercially available glasses, and its ability to block light from mobile phone screens and the sun is excellent. [ABSTRACT FROM AUTHOR]

Konjac glucomannan (KGM) as an emerging natural polymer has attracted increasing interests owing to its film-forming properties, excellent gelation, non-toxic characteristics, strong adhesion, good biocompatibility, and easy biodegradability. Benefiting from these superior performances, KGM has been widely applied in the construction of multiple composite materials to further improve their intrinsic performances (e.g., mechanical strength and properties). Up to now, KGM-based composite materials have obtained widespread applications in diverse fields, especially in the field of biomedical. Therefore, a timely review of relevant research progresses is important for promoting the development of KGM-based composite materials. Innovatively, firstly, this review briefly introduced the structure properties and functions of KGMs based on the unique perspective of the biomedical field. Then, the latest advances on the preparation and properties of KGM-based composite materials (i.e., gels, microspheres, films, nanofibers, nanoparticles, etc.) were comprehensively summarized. Finally, the promising applications of KGM-based composite materials in the field of biomedical are comprehensively summarized and discussed, involving drug delivery, wound healing, tissue engineering, antibacterial, tumor treatment, etc. Impressively, the remaining challenges and opportunities in this promising field were put forward. This review can provide a reference for guiding and promoting the design and biomedical applications of KGM-based composites. [Display omitted] [ABSTRACT FROM AUTHOR]

Mn4+-activated luminescent materials exhibit high color purity red light emission, but their limited water resistance hinders practical applications. In this study, citric and oxalic acids are innovatively employed for surface modification, resulting in luminescent materials with enhanced water resistance while preserving their luminescent intensity. This enhancement provides a prerequisite for their application in anti-counterfeiting films and aqueous fluorescent inks. Furthermore, the potential for optical information storage is successfully demonstrated by utilizing the photochromic fluorescent properties of polyvinyl alcohol films deposited on oxalic acid-modified K 2 SiF 6 :Mn4+. Exploiting the 3 ms day time difference between equivalently and non-equivalently doped Mn4+ fluoride, a millisecond information encryption mode is proposed by combining oxalic acid-modified K 2 SiF 6 :Mn4+ (long decay time, τ = 8.99 ms) and K 3 AlF 6 :Mn4+ (short decay time, τ = 5.31 ms). This mode can be effectively decoded using digital cameras and editing software, achieving high-level anti-counterfeiting capabilities. This work advances the application of highly efficient Mn4+-activated red phosphors in the realm of information security. [ABSTRACT FROM AUTHOR]

Organochlorine pesticides are widespread in soils, sediments and even in groundwater, causing great concern to human health because of its toxicity and carcinogenic effects. The remarkable mineralization and lowered toxicity are particularly important during the removal of organochlorine pesticides. In this study, Pd/CeO 2 was prepared and employed as a bifunctional catalyst, to construct the reduction-oxidation series coupling Electro-Fenton (EF) system. The removal of chlorophenols (CPs) reached over 95% within 10 min at pH 3.0 and a current density of 25 mA/cm2 in Pd/CeO 2 -EF system. The second-order rate constant of CPs degradation was 10.28 L mmol−1 min−1 in Pd/CeO 2 -EF system, which was 29 times as fast as the sum of electrolysis with Pd/CeO 2 (0.24 L mmol−1 min−1) and EF (0.11 L mmol−1 min−1). Dehydrochlorination by Pd [H] contributed to the removal of CPs in Pd/CeO 2 -EF system. The generated reactive oxygen species, mainly OH was also confirmed by ESR to contribute to the removal of CPs. The reduction-oxidation series coupling degradation of CPs in Pd/CeO 2 -EF system increased the TOC removal to 70% in 360 min. The analysis of intermediate products further revealed the reductive and oxidative products in Pd/CeO 2 -EF. Moreover, the system of Pd/CeO 2 -EF exhibited an excellent performance treatment for CPs in actual groundwater. This study provides a new stratagem to eliminate organochlorine pesticides in groundwater environments rapidly and thoroughly. • Pd played as a bifunctional catalyst in electro-Fenton system. • The reduction-oxidation coupling degradation of chlorophenols was achieved. • Dechlorination by Pd [H] and then mineralization by OH for chlorophenols were got. • The main degradation pathway of chlorophenols was proposed. • The stability of Pd/CeO 2 -EF were confirmed in actual groundwater. [ABSTRACT FROM AUTHOR]

• Ions representing the interaction between graphene and copper substrate are observed in ToF-SIMS spectra. • The graphene-related ions and the ions related to graphene-Cu interaction show a similar pattern. • Graphene protects Cu substrate from oxidation. • ToF-SIMS provides direct evidence of the interaction between graphene and Cu foil substrate. The interaction between graphene and different metal substrates is important for preparation of graphene with large area and high quality. The existence of graphene-metal interaction can also alter the electronic properties of graphene. In this study, experiments using time-of-flight secondary ion mass spectrometry (ToF-SIMS) were conducted at 450 °C to investigate the interaction between graphene and Cu foil substrate. In the ToF-SIMS spectra, in addition to graphene and Cu-related peaks, we also found the peaks originated from the interaction between graphene and Cu foil substrate. The distribution of the graphene-related ions and the ions related to the graphene-Cu interaction shows a similar pattern in the ToF-SIMS images; however, the distribution of the ions related to the graphene and the Cu oxide exhibits a complementary pattern, revealing that a graphene-covered Cu surface shows an improved oxidation resistance during annealing processes and storage. This work provides direct and strong evidence showing the interaction between graphene and Cu foil substrate. [ABSTRACT FROM AUTHOR]

In order to improve the desulfurization rate, deep eutectic solvents (DESs) were used for the first time as solvents in the reductive desulfurization process with nickel boride (NB). DES plays a dual role of stabilizer and extracting agent in the desulfurization process. NBs prepared in different solvents were characterized by PSZPA, SAPA, XRD and FTIR spectroscopy. Results indicate that the NBs with small particle size and high specific surface area can be obtained by using DES as the solvent. The desulfurization rate of aromatic sulfides using DESs as the solvent is much higher than that using MeOH/THF as the solvent. The desulfurization rate in different DESs follows the order of tetrabutyl ammonium chloride (TBAC)/polyethylene glycol > TBAC/ethylene glycol > TBAC/glycerol. No chemical reactiong takes place between NB and DESs, and the structures of the DESs remain unchanged after regeneration. [ABSTRACT FROM AUTHOR]

Preparative liquid chromatography has become an important purification method owing to its advantages of high separation efficiency, good reproducibility, and low solvent consumption. Because overloading in preparative liquid chromatography must be performed to increase the throughput in a cycle, nonlinear chromatographic behavior is observed. Therefore, it is crucial to carefully study nonlinear chromatography for the purification of a given product, which facilitates the efficient optimization of the purification parameters. In this work, a method for the development of a purification method using preparative liquid chromatography based on nonlinear chromatography is proposed. Hydroxytyrosol was selected as the subject for method demonstration. Using methanol and ethanol as organic modifiers, the optimum flow rate was determined on three commercial columns entitled C8TDE, C18ME, and C18TDE, respectively. The curves were fitted with the van Deemter equation, with thorough analysis of the A, B, and C terms. Adsorption isotherms were subsequently studied to explore the distribution of solutes between the stationary and mobile phases at equilibrium. C18TDE, 5 vol% ethanol–water, and 0.2 mL/min were selected as the optimal separation material, elution solvent, and flow rate, respectively. Purification of hydroxytyrosol was tentatively confirmed on a C18TDE column with 1.6% sample loading, 90.98% recovery, and 98.01% purity. [ABSTRACT FROM AUTHOR]

Guanine nucleotide-binding protein subunit α14 (GNA14) knockdown was demonstrated to inhibit the proliferation of endometrial carcinoma cells in a recent study; however, its role in hepatocellular carcinoma (HCC) is unknown. In the present study, the clinical significance of GNA14 in HCC was assessed using a dataset of patients with HCC from The Cancer Genome Atlas database. The Integrative Molecular Database of Hepatocellular Carcinoma and Oncomine databases were also used to identify the expression levels of GNA14 in HCC tissues. The association between GNA14 expression levels and clinicopathological features was assessed using the Wilcoxon signed-rank test and logistic regression analysis. Kaplan-Meier curves and Cox regression analysis were applied to evaluate the independent risk factors for clinical outcomes. The present study determined GNA14 DNA methylation levels and tumor-infiltrating immune cells, as well as used Gene Set Enrichment Analysis (GSEA) in HCC. GNA14 mRNA expression levels were lower in HCC compared with normal tissues. Downregulation of GNA14 in HCC was significantly associated with tumor grade, clinical stage and T stage. Furthermore, low expression of GNA14 was an independent predictor for survival outcomes. GNA14 expression levels were partially correlated with the infiltration of B cells and macrophages. Additionally, GSEA analysis revealed that the expression levels of GNA14 were associated with multiple signaling pathways, such as translation, DNA replication, and homologous recombination. In conclusion, low GNA14 expression may be a novel biomarker for diagnosis and prognosis prediction for patients with HCC. [ABSTRACT FROM AUTHOR]

Organic afterglow is a fascinating phenomenon with exceptional applications. However, it encounters challenges such as low intensity and efficiency, and typically requires UV-light excitation and facile intersystem crossing (ISC) due to its spin-forbidden nature. Here, we develop a novel strategy that bypasses the conventional ISC pathway by promoting singlet-triplet transition through the synergistic effects of the intra/intermolecular heavy-atom effect in aromatic crystals, enabling the direct population of triplet excited states from the ground state. The resulting materials exhibit a bright organic afterglow with a remarkably enhanced quantum efficiency of up to 5.81%, and a significantly increased organic afterglow lifetime of up to 157 microseconds under visible light. Moreover, given the high-efficiency visible-light excitable organic afterglow emission, the potential application is demonstrated in lifetime-resolved, color-encoded, and excitation wavelength-dependent pattern encryption. This work demonstrates the importance of the direct population method in enhancing the organic afterglow performance and red-shifting the excitation wavelength, and provides crucial insights for advancing organic optoelectronic technologies that involve triplet states. [ABSTRACT FROM AUTHOR]

Some flaws in a paper written by Jawhar Ghommam and Faïçal Mnif ( IEEE Transactions on Industrial Electronics, vol. 56, no. 10, pp. 3951–3963, Oct. 2009) concerning the coordinated path-following control problem for a group of underactuated surface vessels are indicated and corrected. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA)/starch acetate (SA) base film was prepared by scraping film method with PLA as the base film material, modified SA as the filling phase and polyethylene glycol (PEG) as plasticizer. Chitosan (CS)/tea polyphenol (TP) antibacterial agent was coated on the surface of PLA/SA base film by coating method. The morphology and structure of the composite film were characterized by FTIR, XRD, SEM and thermogravimetric analysis, and the mechanical, optical and antibacterial properties were tested and analyzed. The results showed that CS/TP compound antibacterial agent was well combined with PLA/SA base film. Compared with the PLA/SA base film, when the content of TP (based on the mass of PLA/SA base film, the same below) was 0.4%, the tensile strength of the composite film increased by 29.33%, had good mechanical strength (24.96 ± 0.65 MPa), and the elongation at break increased by 29.34%; There was no obvious change in transparency, the light transmittance decreased by 0.86%; At the same time, the antibacterial composite film had good antibacterial effect on Escherichia coli, Staphylococcus aureus and Bacillus subtilis. PLA/SA/CS/TP antibacterial composite film could be used in food packaging, especially those designed to protect food from light and microbial decay. [ABSTRACT FROM AUTHOR]

For many years, the traditional process of gardenia yellow pigment extraction has produced wastewater containing significant quantities of Geniposidic acid (GSA), a substance that could be put to pharmacological uses if it could be effectively recovered. This study aimed to provide an efficient adsorption material, D08, for recycling GSA. Batch experiments showed that adsorption capacity depends on initial concentration and temperature. The maximal adsorption capacity of GSA onto an anionic exchanger reached 310 mg/g. The p K value of GSA was determined to be 4.21. Pore diffusion coefficients ( D ) of GSA for 283, 298 and 313 K were 3.274 × 10, 5.069 × 10 and 7.356 × 10 m/s, respectively. Recovery efficiency of GSA was achieved to 99.81 %. In comparison with pseudo first-order and pseudo second-order equations, the PDM model demonstrated the best fit to the kinetics data of GSA adsorption. Adsorption/desorption experiments proved that D08 offers great adsorption capacity, high adsorption rate and good repeatability. In order to help us to accurately comprehend the mass transfer process, numerical simulation and post-processing to variables c( r, t) and q( r, t) were performed to clarify the adsorption process. [ABSTRACT FROM AUTHOR]

Based on one-year observation, the concentration, sources, and potential source areas of volatile organic compounds (VOCs) were comprehensively analyzed to investigate the pollution characteristics of ambient VOCs in Haikou, China. The results showed that the annual average concentration of total VOCs (TVOCs) was 11.4 ppbV, and the composition was dominated by alkanes (8.2 ppbV, 71.4%) and alkenes (1.3 ppbV, 20.5%). The diurnal variation in the concentration of dominant VOC species showed a distinct bimodal distribution with peaks in the morning and evening. The greatest contribution to ozone formation potential (OFP) was made by alkenes (51.6%), followed by alkanes (27.2%). The concentrations of VOCs and nitrogen dioxide (NO 2) in spring and summer were low, and it was difficult to generate high ozone (O 3) concentrations through photochemical reactions. The significant increase in O 3 concentrations in autumn and winter was mainly related to the transmission of pollutants from the northeast. Traffic sources (40.1%), industrial sources (19.4%), combustion sources (18.6%), solvent usage sources (15.5%) and plant sources (6.4%) were identified as major sources of VOCs through the positive matrix factorization (PMF) model. The southeastern coastal areas of China were identified as major potential source areas of VOCs through the potential source contribution function (PSCF) and concentration-weighted trajectory (CWT) models. Overall, the concentration of ambient VOCs in Haikou was strongly influenced by traffic sources and long-distance transport, and the control of VOCs emitted from vehicles should be strengthened to reduce the active species of ambient VOCs in Haikou, thereby reducing the generation of O 3. [Display omitted]. [ABSTRACT FROM AUTHOR]