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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]

In this paper, a nonlinear partial-state feedback control is designed for a 3-DOF pantograph–catenary system by using backstepping approach, such that the contacting force of the closed-loop system is capable of tracking its reference profile. In the control design, the pantograph–catenary model is transformed into a triangular form, facilitating the utilization of backstepping. Derivatives of virtual controls in backstepping are calculated explicitly. A high-order differentiator is designed to estimate the unknown time derivatives of elasticity coefficient; and an observer is proposed to reconstruct the unmeasurable states. It can be proved theoretically that, with the proposed nonlinear partial-state feedback control, the tracking error of the contacting force is ultimately bounded with tunable ultimate bounds. Theoretical results are demonstrated by numerical simulations. • The backstepping approach is firstly applied to control design for pantograph–catenary system. • The closed-loop system is capable of tracking not only constant reference contacting force but also time-varying periodic reference forces. • A high-order differentiator is designed to approximate the unknown derivatives of time-varying elasticity coefficient. • A simple observer is designed to reconstruct the un-measurable system states. [ABSTRACT FROM AUTHOR]

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]

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]

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]

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]

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]

Sepsis-associated encephalopathy (SAE) is a common complication of sepsis caused by neuroinflammation. Electroacupuncture (EA) can be used to treat SAE, but the underlying mechanism is not clear. Lack of PICK1 further aggravates the inflammatory response in mice with sepsis. Therefore, we sought to investigate whether PICK1 is involved in the protective effects of electroacupuncture to SAE. In this study, mice were treated with EA after lipopolysaccharide (LPS) treatment. Behavioral tests; microglial activity of hippocampus; neuron survival and the inflammatory factors PICK1 and TLR4, as well as TLR4-related proteins, such as ERK, JNK, and P38, were assessed after EA treatment. PICK1, TLR4, and TLR4-related proteins, as well as PICK1-TLR4 complex levels were assessed in BV2 cells treated with LPS, PICK1 siRNA, or PICK1 polypeptide. The results indicated that EA could improve neurological assessment and reduce activation of microglial and TLR4 and expression of proinflammatory cytokines. EA also reduced the expression of TLR4 and phosphorylation of ERK/JNK/P38 while, increased the expression of PICK1 and TLR4 complexes. PICK1 knockdown further promoted the expression of TLR4 and phosphorylation of ERK/JNK/P38 in BV2 cells, but this effect was reversed by PICK1 polypeptides. These results suggest that EA may reduce neuroinflammation responses, decrease inflammatory factors, and finally, protect SAE by increasing the formation of PICK1-TLR4 complexes in microglia. • Electroacupuncture prevents LPS- induced neuroinflammation in mice. • Electroacupuncture up-regulate PICK-TLR4 complexes in hippocampus. • PICK-TLR4 complexes in the microglia partakes in electroacupuncture prevents neuroinflammation. [ABSTRACT FROM AUTHOR]

Owing to the superior photoluminescence property, low toxicity and good biocompatibility, nitrogen-doped graphene quantum dots (NGQDs) have been regarded as promising nanomaterials for biological applications such as bioimaging. However, many of the preparation methods are complicated, high cost, eco-unfriendly, and with a low product yield. Here, we demonstrate a novel top-down approach for NGQDs preparation, in which the low cost graphite was used as a precursor, ammonium persulfate as an oxidative molecule and nitrogen source, and H 2 O 2 as an oxidative agent, N -methyl-2-pyrrolidone as a solvent and potential functionalizer. Meanwhile, the solvent extraction was applied for the first time to purify NGQDs. The separated NGQDs display green and blue fluorescence, deriving from the difference sizes and nitrogen doped types. The total product yield of NGQDs is calculated to be about 52%, containing 88% of green-emissive NGQDs and 12% of blue-emissive NGQDs. Meanwhile, our NGQDs own low cytotoxicity, and display a good bioimaging performance in the in vitro and in vivo investigation. The synthesis idea in our work might be also applicable to obtain other kinds of quantum dots from the readily obtainable bulk materials. Unlabelled Image • A simple and eco-friendly method was developed for preparation of nitrogen-doped graphene quantum dots. • Two different kinds of nitrogen-doped graphene quantum dots with blue- and green-emission, respectively, were obtained. • The nitrogen-doped graphene quantum dots with superior fluorescent properties can be used for bioimaging applications. [ABSTRACT FROM AUTHOR]

The pollution characteristics of volatile organic compounds (VOCs) in urban and background regions in Hainan province, China, were determined based on field measurements of CO, NO, NO 2 , O 3 , VOCs, and meteorological parameters conducted at Haikou (HK, an urban site) and Wuzhishan (WZS, a background site) in 2019. The annual average concentration of VOCs at HK was 13.1 ppb, which was 2.2 times higher than that at WZS (6.0 ppb). VOC concentrations at HK were higher in winter, whereas there was no significant monthly variation at WZS. Diurnal variations in VOCs were characterized by two peaks at HK, attributable to emissions during morning and evening rush-hour traffic. At WZS, the diurnal variations of VOCs were characterized by one peak at 13:00–16:00, corresponding to the high temperature and intense sunlight in the afternoon. The total O 3 formation potential of ambient VOCs was 135.1 g g−1 at HK and 80.6 g g−1 at WZS, with the O 3 formation potential of alkenes accounting for 53.4% and 47.2%, respectively. The potential source region of VOCs at both sites was likely the southeastern ocean region of China (i.e., Guangdong, Guangxi, Hunan, and Jiangxi provinces) and Vietnam, Cambodia, and Thailand. Using on an empirical kinetic modeling approach, O 3 formation at HK occurred under a mixed-limited region, and at WZS under a NOx-limited region. Traffic emissions were the largest contributor to VOCs at HK, accounting for 38.7%, followed by solvents (19.6%), combustion (15.2%), industrial sources (15.0%), and plant sources (11.5%). At WZS, traffic accounted for 39.6% of VOCs, similar to HK, whereas the contribution of industrial sources (22.1%) was higher. Although there are few vehicles and little industry around WZS, the long-distance transport of VOCs emitted elsewhere by these sources had a significant influence on the region's VOCs. The contribution of plant sources of VOCs was 1.5 times higher at WZS (17.0%) than at HK. None of the VOC species posed significant non-carcinogenic or carcinogenic risks at either HK or WZS. [Display omitted] • The annual average concentration of VOCs at HK was 2 times higher than that at WZS. • Isoprene, ethene, and cis -2-butene were the dominant OFP species at both HK and WZS. • O 3 formation in HK was under a mixed-limited region. • None of the VOC species posed a significant non-carcinogenic or carcinogenic risk. [ABSTRACT FROM AUTHOR]

Transformers with long-range dependency and data specificity act as an effective means of classifying insect pests in agricultural engineering. Although many methods have been proposed to confine the range of self-attention within a local region to reduce the computation complexity, none of them can reduce the number of model parameters. Moreover, the self-attention mechanism usually causes query tokens to focus excessively on image patches, which limits the effective receptive field and the long-range dependence. To address these issues, this paper establishes a novel D ilated- W indows-based Vi sion T ransformer with E fficient- S uppressive-self-attention (DWViT-ES) architecture, which includes efficient-self-attention (ESA), dilated window (DW), and suppressive-self-attention (SSA) as its core components. The ESA simplifies the successive linear Transformations to reduce the number of model parameters and computational costs. Meanwhile, the DW and SSA expand the effective receptive field of self-attention mechanism to prevent query tokens from focusing on similar and close regions, thereby preventing the loss of useful information. Finally, experiments show that the DWViT-ES only has 19.6 M parameters and 3.5G FLOPs (over 20% reductions vs. 19.6 M and 4.5G of Swin-T). Meanwhile, the DWViT-ES training from scratch has 71.6% top-1 accuracy on the IP102 dataset (2.4% absolute improvement of Swin-T); after fine-tuning on Imagenet-1K, the DWViT-ES achieves 76.0% and 78.7% top-1 accuracy on IP102 and CPB (0.1% and 0.9% absolute improvement of Swin-T), respectively. Meanwhile, practical deployment on a mobile-embedded device is presented, which validates the feasibility of the DWViT-ES. [ABSTRACT FROM AUTHOR]

Perturbation of Fe(III)-bearing oxic environments by reduced species such as sulfide occurs widely in natural and engineered systems. However, whether hydroxyl radicals (OH) can be produced in these environments remains unexplored. Here we show that sulfide drives OH production in Fe(III) oxyhydroxides suspensions under neutral and oxic conditions. For lepidocrocite, ferrihydrite and goethite suspensions at 11.2 mM Fe, the addition of 0.5 mM sulfide produced 14.2, 14.3 and 22.4 μM OH within 120 min, respectively. With addition of sulfide to lepidocrocite suspensions at 11.2 mM Fe, the cumulative OH concentration within 120 min increased from 0 to 14.2, 25.2, 52.6 and 63.1 μM when sulfide dosage increased from 0 to 0.5, 2.5, 5 and 7.5 mM, respectively. At a fixed sulfide dosage of 5 mM, the cumulative OH concentration increased with increasing the number of sulfide additions. The mechanisms of OH production were attributed to the generation of surface-bound Fe(II), most likely in the form of >FeIIOH 2 +, and Fe(II) in the solid phase or FeS from the reactions between sulfide and Fe(III), followed by O 2 activation. OH production could take place until depletion of sulfide. Finally, we found that the generated OH could oxidize the coexisting redox-active substances like phenol under neutral and oxic conditions. Our findings reveal that sulfide perturbation of Fe(III)-bearing oxic environments is a new source of OH, and contaminants oxidation by OH necessitates consideration in these environments. A new abiotic pathway of dark OH production. Image 1 •. OH can be produced in oxic Fe(III)-bearing environments perturbed by sulfide. • Surface-bound Fe(II) and Fe(II) in the solid phase or FeS were produced in sulfide/Fe(III)/O 2 systems. • O 2 activation by surface-bound Fe(II) and/or Fe(II) in the solid phase or FeS was responsible for. OH production. • The produced. OH could oxidize organic contaminants. • A new abiotic pathway was proposed for dark. OH production in the environment. [ABSTRACT FROM AUTHOR]

Highlights • Desorption/elution simulation of GSA was studied in COMSOL efficiently. • A superficial desorption rate constant was considered at the liquid–solid interface. • Equilibrium time is decreased by increasing the concentration of desorbent HCl. • The recycle percentage of GSA is acceptable in a series of adsorption–elution cycles. Abstract For several decades, plenty of iridoid glycosides including geniposide (GS) and geniposidic acid (GSA) in the gardenia yellow pigment extraction waste water was not recovered effectively. This study is aimed to supply an efficient GSA recycling route. In this study, a model incorporating a superficial desorption rate constant was applied to the batch GSA desorption process, i.e., recycling, for verification. Then, the model was further developed to research the feasibility in dynamic column elutions simulation through porous uniform media. The simulation approach was done by coupling velocity field and mass transfer equations using COMSOL Multiphysics™ Finite element method, with appropriate mesh refinement was employed to solve the equation system. The HCl solutions ranging from 0.03 mol/L to 0.06 mol/L were used to desorb/elute the GSA from a presaturated polymeric porous anionic resin D08. Good results were accomplished in terms of ion exchange desorption rate and GSA recovery. The pore diffusion model (PDM) considering counter ion was established to describe the desorption/elution kinetics in the batch/column experiment. By the least square fitting method, the superficial desorption rate constant K d of GSA/HCl reaction on the ion-exchange sites of porous resin was fitted to 0.116 L/(mol s). Subsequently, this value was sequentially applied in the simulation of the dynamic elution process. The individual pore diffusion coefficients for GSA and Cl− were estimated to be 5.07 × 10−10 and 1.77 × 10−9 m2/s, respectively. In order to validate the simulation feasibility of this pore diffusion model to a dynamic column elution process, the effects of HCl concentration, flow rate and column's height/diameter ratio on the column performance were investigated systematically. The results from this work should serve as motivation for further experimental and theoretical study in the scaling-up of GSA purification process. Finally, repeated adsorption–elution column cycles were simulated by the PDM model well. [ABSTRACT FROM AUTHOR]

Abstract In this work, a mesoporous Fe3+ type ion exchanger (DOW-3) was used to adsorb the geniposide (GS) involved in gardenia yellow pigment waste water. To test its viability, the mass transfer zone (MTZ) in dynamic adsorption column that plays an important role in the future scale-up of the GS adsorption process was studied systematically. Simulation of the MTZ behavior under various operation conditions in a packed adsorption column enabled the predictions of breakthrough curves of GS for the mesoporous adsorbent. Several modes of mass transport and processes taking place simultaneously, such as permeation, convection, dispersion and adsorption equilibrium were incorporated in the proposed model. Modeling process firstly affected the behavior of MTZ when it formed and moved throughout the column, and then had a much greater impact on the shape of breakthrough curve in the simulation. The dynamics of MTZ were studied under different adsorption conditions such as various column heights, flow rates and inlet concentrations. Moreover, the post-processing technique and 3D visualization of MTZ simulation results were capable of demonstrating the expanding and progressing of the MTZ related to the adsorption isotherm. The basic findings of MTZ dynamics will be very useful for process scale up. Additionally, the effective molecule docking results obtained from this study, help us fully understand the contribution of various molecular forces in the adsorption mechanism. Graphical abstract Image Highlights • A mesoporous iron-type ion exchanger was firstly used in GS adsorption processes. • PDEs in the column model were solved in Comsol Multiphysics by a 3D technology. • Overall mass transfer coefficient K overall were obtained by this model. • Behavior and properties of MTZ was studied detailedly in adsorption experiments. • Molecule docking results well explains the adsorption mechanism of GS molecule. [ABSTRACT FROM AUTHOR]

Abstract: A novel electro-Fenton process based on Pd-catalytic production of H2O2 from H2 and O2 has been proposed recently for transforming organic contaminants in wastewaters and groundwater. However, addition of Fe(II) complicates the operation, and it is difficult to recycle Pd catalyst after treatment. This study attempts to synthesize an integrated catalyst by loading Pd onto magnetic Fe3O4 nanoparticles (Pd/MNPs) so that H2O2 and Fe2+ can be produced simultaneously in the electrolytic system. In an undivided electrolytic cell, phenol, a probe organic contaminant, is degraded by 98% within 60 min under conditions of 50 mA, 1 g/L Pd/MNPs (5 wt% Pd), pH 3 and 20 mg/L initial concentration. The degradation rate peaks at pH 3, increases with increasing Pd loading and electric current and decreases with increasing initial concentration. A distinct mechanism, reductive dissolution of solid Fe(III) in Fe3O4 by atomic H chemisorbed on Pd surface, is responsible for Fe2+ production from Pd/MNPs. The efficiency of phenol degradation can be sustained at the same level for ten times of repeated treatment using the Pd/MNPs catalyst. The variations of main crystal structure and magnetic property of catalysts are minimal after treatment, but low concentrations of Pd leached, which needs further evaluation. [Copyright &y& Elsevier]

Highlights: [•] A cheap Cu/C catalyst was synthesized for electro-Fenton process. [•] Cu/C catalyzed the electrolytic degradation of phenol. [•] OH radicals were the dominant ROS for phenol degradation. [•] Degradation under different conditions was investigated. [•] The performance of Cu/C was lower compared with Pd/C. [Copyright &y& Elsevier]

• The involvement of PICK1 in Sepsis-associated Encephalopathy was first identified. • Deficiency of PICK1 aggravates inflammatory damage and overactivation of the TLR4 pathway. • PICK1 plays a protective role in Sepsis-associated Encephalopathy by forming a complex with TLR4. The treatment options for sepsis-associated encephalopathy caused by systemic inflammation are still not sufficient. Protein kinase C interaction protein 1 (PICK1) has attracted much attention because of its important physiological functions in many tissues. However, its role in sepsis-associated encephalopathy remains elusive. Our study results revealed that the expression levels of PICK1 protein in mice with lipopolysaccharide-induced sepsis-associated encephalopathy were not significantly changed, but PICK1 deficiency led to excessive activation of microglia and Toll-like receptor (TLR)4 pathways, which aggravated the sepsis- associated encephalopathy. We also observed that PICK1 and TLR4 form a complex in microglial cells, thereby providing brain protection. These findings contribute to our understanding of the important role of PICK1 in sepsis and may provide novel therapeutic targets to treat sepsis-associated encephalopathy. [ABSTRACT FROM AUTHOR]

As the general public rely more on social media for accessing health information, it is important to investigate how patients with complex chronic diseases use social media for symptom management. Guided by social cognitive theory, this study analyzes Crohn's disease patients' use of health information and its impact on their clinical course. The results show that health information on social media had provided the patients significant informational, emotional, and peer support, which mediated their treatment understanding, symptom management, and trust in doctors. When their symptoms went worse, the patients reported obtaining more support from social media groups, leading to better treatment understanding. A better treatment understanding resulted in more trust in doctors. But using social media groups that were not monitored by physicians reduced their trust in doctors. Initial evidence shows that health information could benefit patients like a complementary medical intervention. As an exploratory study, the results should be interpreted with caution as some findings may not be generalized to all complex chronic disease patients. This endorses the importance of studying patients' health information processing on social media as part of the effort for improving chronic illness care. • Social media have potential to improve Crohn's disease patients' clinical course. • Health information on social media offers informational, emotional and peer support. • The support alters treatment understanding, symptom control, and trust in doctors. • Patients' interaction with doctors on social media affects health outcomes. • Health information may function like medical interventions in the clinical course. [ABSTRACT FROM AUTHOR]

Rebaudioside A (RA) self-assembled into ultrasmall nanomicelles can be utilized as ocular drug delivery system; nevertheless, the therapeutic efficacy of RA micelles has not evaluated thus far. In this manuscript, the RA micelles are thought to strengthen the therapeutic effects of pterostilbene (Pt). Results showed that Pt can be highly encapsulated into RA micelles with ultrasmall particle sizes (3.99 ± 0.03 nm) with a uniform distribution (polydispersity index, PDI = 0.184 ± 0.008). RA-Pt exhibited pronounced improvement for the in vitro antioxidant activity and the in vitro membrane permeation of Pt. RA-Pt exhibited good ocular tolerance. The use of RA-Pt led to the significant improvement in the in vivo intraocular permeation of Pt as well as the improvement in the in vivo anti-inflammatory efficacy. The in vivo evaluation of antioxidant effects revealed that RA-Pt exhibits improvement in suppressing the generation of oxidative stress and inducing the enzymes of reactive oxygen species (ROS) degradation. Furthermore, RA-Pt was confirmed to exhibit a strong treatment efficiency for corneal alkali burns. These findings indicate that RA-based self-assembled ultrasmall nanomicelles demonstrate tremendous potential toward the improvement in the ocular bioavailability as well as a therapeutic effect of poor aqueous soluble drugs such as Pt. [ABSTRACT FROM AUTHOR]