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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]

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]

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]

Spartina alterniflora is ecologically important in its original habitat; however, it has caused controversy since it was introduction into China (now it has been spreading rapidly on the Jiangsu, Shanghai, Zhejiang and Fujian coasts). The purpose of the present contribution is, on the basis of an analysis and synthesis of existing data sets, to evaluate the environmental-ecological effects of S. alterniflora, and to identify the relevant scientific problems that require further research in the future. Investigations have shown that, by reducing the near-bed shear stress associated with tidal currents, S. alterniflora can enhance the settling flux of suspended sediment and deposition rate on the tidal flats over the region. Further, field survey and analysis indicate that the S. alterniflora salt-marsh has a high primary production and provides a new type of habitat for the native benthic fauna. Some macro-, meio- and micro-fauna that used to live in the native salt-marshes have adapted to the S. alterniflora salt-marsh, forming a new ecosystem. Under the influences of a number of background factors, such as latitude variations and the coastal type, the environmental-ecological changes induced by Spartine have regional differentiations. To the north of Hangzhou Bay, with a high position of the pre-Holocene stratum base, a large width of the tidal flats, and a gentle bed slope, only a small part of the intertidal zone is occupied by the S. alterniflora salt-marsh. Here, the S. alterniflora salt-marshes mainly play a positive role in coastal protection and ecosystem functioning. In contrary, to the South of Hangzhou Bay, The pre-Holocene deposits are situated in relatively deeo waters, and the width of the tidal flats formed within coastal embayments is relatively narrow. As such, the expansion of S. alterniflora has squeezed the living space of other intertidal organisms, thus has a negative ecological effect. Therefore, the regional differentiation of the Spartina effects should be sufficiently considered in coastal development and management. Furthermore, in order to predict the future evolution of the S. alterniflora wetlands over the region, in addition to in situ monitoring and measurements, an ecosystem dynamic model should be established, taking into account the coupling of the rerrestrial and marine environmental-ecological processes. [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]

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]

Background: Considerable research has been devoted to examining the mental health conditions of patients with COVID-19 and medical staff attending to these patients during the COVID-19 pandemic. However, there are few insights concerning how the pandemic may take a toll on the mental health of the general population, and especially of nonpatients (ie, individuals who have not contracted COVID-19).Objective: This study aimed to investigate the association between social media use and mental health conditions in the general population based on a national representative sample during the peak of the COVID-19 outbreak in China.Methods: We formed a national representative sample (N=2185) comprising participants from 30 provinces across China, who were the first to experience the COVID-19 outbreak in the world. We administered a web-based survey to these participants to analyze social media use, health information support received via social media, and possible psychiatric disorders, including secondary traumatic stress (STS) and vicarious trauma (VT).Results: Social media use did not cause mental health issues, but it mediated the levels of traumatic emotions among nonpatients. Participants received health information support via social media, but excessive social media use led to elevated levels of stress (β=.175; P<.001), anxiety (β=.224; P<.001), depression (β=.201; P<.001), STS (β=.307; P<.001), and VT (β=.688; P<.001). Geographic location (or geolocation) and lockdown conditions also contributed to more instances of traumatic disorders. Participants living in big cities were more stressed than those living in rural areas (P=.02). Furthermore, participants from small cities or towns were more anxious (P=.01), stressed (P<.001), and depressed (P=.008) than those from rural areas. Obtaining more informational support (β=.165; P<.001) and emotional support (β=.144; P<.001) via social media increased their VT levels. Peer support received via social media increased both VT (β=.332; P<.001) and STS (β=.130; P<.001) levels. Moreover, geolocation moderated the relationships between emotional support on social media and VT (F2=3.549; P=.029) and the association between peer support and STS (F2=5.059; P=.006). Geolocation also interacted with health information support in predicting STS (F2=5.093; P=.006).Conclusions: COVID-19 has taken a severe toll on the mental health of the general population, including individuals who have no history of psychiatric disorders or coronavirus infection. This study contributes to the literature by establishing the association between social media use and psychiatric disorders among the general public during the COVID-19 outbreak. The study findings suggest that the causes of such psychiatric disorders are complex and multifactorial, and social media use is a potential factor. The findings also highlight the experiences of people in China and can help global citizens and health policymakers to mitigate the effects of psychiatric disorders during this and other public health crises, which should be regarded as a key component of a global pandemic response. [ABSTRACT FROM AUTHOR]