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The transport of biochar nano-particles (BCNPs) influenced by complex physicochemical factors is systematically investigated through the transport experiments combined with the interfacial chemistry theory and numerical modeling methods. The two-dimensional (2D) distributions of Derjaguin-Landau-Verwey-Overbeek (DLVO) interaction energy are obtained and a new indicator of DLVO barrier (ξ DB) is proposed to identify the inflection point related to agglomeration and deposition of BCNPs. Results suggest the mobility of BCNPs in porous media decreases with ionic strength, and the inhibitory effect of divalent cations on BCNPs transport is stronger than that of monovalent cations. However, the mobility of BCNPs is enhanced by the increases in pH and humic acid concentrations. In addition, the higher the concentration of BCNPs, the higher the retention of BCNPs in saturated porous media. The mobility of BCNPs is enhanced under the conditions of high flow velocity. A combined value of DLVO energy barriers is calculated and results suggest the decision coefficient (R2) decreases with the fraction of DLVO energy barrier of BCNPs-BCNPs, indicating that the interaction between BCNPs and quartz sand (QS) plays a major role in the transport of BCNPs in porous media. Afterward, the continuous values of two-site kinetic transport parameters of BCNPs in porous media as a function of hydrochemical factors can be predicted by the combined value of DLVO energy barriers. Simultaneously, the critical hydrochemical conditions related to BCNPs mobility can be quantitatively determined by a combination of column experiment, DLVO interaction energy and transport model. The critical hydrochemical conditions are IS(Na+)= 29.3–29.4 mM, IS(Ca2+)= 2.50–2.55 mM, pH= 3.36–3.37, HA concentration= 3.68–5.84 mg·L−1. The findings are important for understanding the transport behavior and mechanism of BCNPs in porous media, and accurate prediction and assessment of BCNPs transport patterns in soil-groundwater systems. [Display omitted] • The interaction between BCNPs and QS plays a major role in transport patterns. • A new indicator of DLVO barrier is proposed to identify inflection point. • Flow velocity, pH and HA enhance BCNPs mobility, while cations inhibit its mobility. • k 1 , k 1d , R RE and P C/C0 increase linearly with DLVO energy barrier, while k 2 and S max2 show a decreasing tend. • Critical hydrochemical factors of BCNPs is accurately obtained by DLVO, experiments and model. [ABSTRACT FROM AUTHOR]

Investigation of the change rate for contaminant parameters is important to characterize dense non-aqueous phase liquid (DNAPL) transport and distribution in groundwater systems. In this study, four experiments of perchloroethylene (PCE) migration are conducted in two-dimensional (2D) sandboxes to characterize change rates of PCE saturation (So) and PCE–water interfacial area (AOW) under different conditions of salinity, surface active agent, and heterogeneity. Associated representative elementary volume (REV) of the change rate of So (So rate) and change rate of AOW (AOW rate) is derived over the long-term transport process through light transmission techniques. REV of So rate (SR-REV) and REV of AOW rate (AR-REV) are estimated based on the relative gradient error ( ε g i ). Regression analysis is applied to investigate the regularity, and a model based on a back-propagation (BP) neural network is built to simulate and predict the frequencies of SR-REV and AR-REV. Experimental results indicated the salinity, surface active agent, and heterogeneity are important factors that affect the So rate, AOW rate, SR-REV, and AR-REV of the PCE plume in porous media. The first moment of the PCE plume along the vertical direction is decreased under conditions of high salinity, surface active agent, and heterogeneity, while these factors have different effects on the second moment of the PCE plume. Compared with the salinity and surface active agent, heterogeneity has the greatest effect on the GTP, the distributions of the So rate and AOW rate along the depth, and dM, dI. For SR-REV, the standard deviation is increased by the salinity, surface active agent, and heterogeneity. Simultaneously, the salinity and heterogeneity lead to lower values of the mean value of SR-REV, while the surface active agent increases the mean value of SR-REV. However, the mean and standard deviation of AR-REV have no apparent difference under different experimental conditions. These findings reveal the complexity of PCE transport and scale effect in the groundwater system, which have important significance in improving our understanding of DNAPL transport regularity and promoting associated prediction. [ABSTRACT FROM AUTHOR]

This article investigates the problems of structural balance and distributed control for a high-order signed network with generic linear dynamics. A novel approach is proposed to analyze the structural balance of a general network based on the strongly connected components of the topology graph and the Frobenius normal form of the adjacency matrix. To address the distributed control of high-order signed networks, both state-feedback and observer-type algorithms are developed on the basis of low-gain strategies, where a unified framework is presented to construct full- or reduced-order observers. The dynamical behaviors of the signed network under the proposed algorithms are systematically explored, where the nontrivial final network state is computed by employing an eigenvector-based approach. The theoretical results are illustrated by numerical examples. [ABSTRACT FROM AUTHOR]

This paper is concerned with the finite-time stability and stabilization problems for a class of hybrid systems, which consists of discrete-time continuous-valued and Boolean dynamics. First, we introduce the so-called systems briefly and give the algebraic form of the systems via Khatri–Rao product and semi-tensor product (STP, i.e., Cheng product). Next, we originally propose the concept of finite-time stability (FTS) for the hybrid systems. Furthermore, some criteria of FTS for the hybrid systems are provided. Via a lemma we present, the computational complexity of the condition on FTS for the logical part could be reduced to O (1). Based on these obtained results, two classes of controllers, state feedback controllers and logical controllers, are designed. Finally, two numerical examples are given to demonstrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

Hydrochemistry and isotopes are studied for characterizations of geothermal waters, groundwaters, and surface waters in Leizhou Peninsula (LZ) and the northern part of Hainan Island (HN) across the tensile-tectonic Qiongzhou Strait, southern China. Water chemistry results showed that most geothermal waters are of alkaline and HCO3-Na types, while shallow groundwater samples were significantly different with HCO3-Ca, HCO3-Mg, and HNO3-Ca types. Stable isotope data indicated that the source of LZ geothermal waters is of atmospheric precipitation, while HN geothermal water has a slight "oxygen drift". Cation geothermometers and silica geothermometers could appropriately predict reservoir temperatures. Based on multicomponent mineral equilibria and quart geothermometer without steam loss, reservoir temperatures were estimated to be in the range of 65.0°C to 165.0°C at an average circulation depth of 2023 m, substantiated with data from a thousand-meter-depth borehole. The saturation indexes (SI) simulated by PHREEQC and Na-K-Mg triangle diagram revealed that the chemical components in the geothermal waters are possibly derived from water-rock interactions at high temperatures. Four simulation paths were established to calculate the mass flux of minerals by PHREEQC program. The hydrothermal circulation process of the volcanic rocks on both sides of the Qiongzhou Strait was similar, but the water-mineral reactions of Leizhou Peninsula were more intense. During the high-temperature hydrothermal deep circulation in the central part of Hainan Island, the molar transfer was low and the degree of mineral reaction is weak. Finally, the geothermal genetic mechanism for the study area of the extensional geostructure was proposed. The findings mark the characteristics for the tensile-tectonic region in slight "oxygen shift", low values of 87Sr/86Sr for possible deep source from the mantle, and higher reservoir temperatures at shallower circulation depths. [ABSTRACT FROM AUTHOR]

Recycling of polyester waste has become a focus of global attention in recent years. Herein, a novel bimetallic catalyst, CoMo@NC derived from Mo@ZIF-CoZn, has been prepared, which can be applied in hydrogenolysis for recycling terephthalate-based polyesters (polyethylene terephthalate (PET) and polybutylene terephthalate (PBT)), converting PET to the valuable monomer terephthalic acid (PTA) in high yield within 10 hours at 260 °C, under atmospheric H2. A distinct enhancement in the catalytic performance of this catalyst is observed when compared with monometallic catalysts, which can be ascribed to the "synergistic catalysis" between Mo-sites and Co-sites inside the bimetallic catalyst. The recyclability test indicated that this catalyst could be reused for at least six times with stable activity. This work highlights new possibilities for bimetallic catalysts applied in sustainable chemistry. [ABSTRACT FROM AUTHOR]

[Display omitted] • Groundwater vulnerability zonation investigation is conducted for GHM Greater Bay Area. • Three different perspectives are comprehensively considered in this study. • Groundwater risk, function value and contamination status are superposed using the AHP method. • Quantification and visualization of groundwater contamination prevention regionalization. • The AHP-DRASTICH model is an effective method to evaluate the groundwater risk in shallow aquifers. The groundwater contamination assessment and prevention regionalization are an important part of groundwater investigation, which is of great significance to groundwater environmental management and contamination control. Although the Guangdong-Hong Kong-Macao Greater Bay Area (GHM Greater Bay Area) has faced significant groundwater contamination since 2020, there's been no investigation into its vulnerability zonation. In this paper, groundwater in a typical area of south China was taken as the research object. We analyzed groundwater contamination risk by considering both the groundwater vulnerability and the load from contamination sources. Using the analytic hierarchy process (AHP) method, we superposed the groundwater risk, function value and contamination status, and realized the quantification and visualization of groundwater contamination prevention regionalization. Based on the DRASTIC model, the zones of low, moderate, high, and very high vulnerability are respectively 14.2 %, 24.28 %, 37.67 %, and 20.45 % of the study area. Results show that the groundwater vulnerability grade in the area is III-IV, which means it is easy to be polluted. The functional value of groundwater in the south-central part of the region is relatively high. Most of the areas with high prevention and control levels are located in plain areas and the Piedmont plain area with an area of 460 km2. The secondary control levels (key protection area) are mainly located in the middle, southwest, and northeast of the plain, with an area of 6944 square kilometers. Consequently, the ideas and contamination prevention zone maps might provide a scientific foundation for long-term planning and management and groundwater conservation in the Guangdong-Hong Kong-Macao Greater Bay Area and peripheral zones. [ABSTRACT FROM AUTHOR]

Two separate groups of geothermal waters have been identified in the coastal region of Guangdong, China. One is Xinzhou thermal water of regional groundwater flow system in a granite batholith and the other is thermal water derived from shallow coastal aquifers in Shenzao geothermal field, characterized by high salinity. The hydrochemical characteristics of the thermal waters were examined and characterized as Na-Cl and Ca-Na-Cl types, which are very similar to that of seawater. The hydrochemical evolution is revealed by analyzing the correlations of components versus Cl and their relative changes for different water samples, reflecting different extents of water-rock interactions and clear mixing trends with seawaters. Nevertheless, isotopic data indicate that thermal waters are all of the meteoric origins. Isotopic data also allowed determination of different recharge elevations and presentation of different mixing proportions of seawater with thermal waters. The reservoir temperatures were estimated by chemical geothermometries and validated by fluid-mineral equilibrium calculations. The most reliable estimates of reservoir temperature lie in the range of 148–162°C for Xinzhou and the range of 135–144°C for Shenzao thermal waters, based on the retrograde and prograde solubilities of anhydrite and chalcedony. Finally, a schematic cross-sectional fault-hydrology conceptual model was proposed. [ABSTRACT FROM AUTHOR]

This paper investigated the deep fault thermal flow processes in the Xinzhou geothermal field in the Yangjiang region of Guangdong Province. Deep faults channel geothermal energy to the shallow ground, which makes it difficult to study due to the hidden nature. We conducted numerical experiments in order to investigate the physical states of the geothermal water inside the fault zone. We view the deep fault as a fast flow path for the thermal water from the deep crust driven up by the buoyancy. Temperature measurements at the springs or wells constrain the upper boundary, and the temperature inferred from the Currie temperature interface bounds the bottom. The deepened boundary allows the thermal reservoir to revolve rather than to be at a fixed temperature. The results detail the concept of a thermal reservoir in terms of its formation and heat distribution. The concept also reconciles the discrepancy in reservoir temperatures predicted from both quartz and Na-K-Mg. The downward displacement of the crust increases the pressure at the deep ground and leads to an elevated temperature and a lighter water density. Ultimately, our results are a first step in implementing numerical studies of deep faults through geothermal water flows; future works need to extend to cases of supercritical states. This approach is applicable to general deep-fault thermal flows and dissipation paths for the seismic energy from the deep crust. [ABSTRACT FROM AUTHOR]

Barium strontium titanate (BST) thin films deposited on stainless steel (SS) substrates can be expected for their potential applications in MEMS-structure tunable microwave devices. In this paper, two sandwich-like structures with varied average Ba/Sr ratio of BST thin films, BaSrTiO layer in the middle or at ends, on LaNiO buffered SS substrates were fabricated by sol-gel technique, and meanwhile were theoretically carried out via a modified phenomenological model. Results show that dielectric constant and tunability of such BST films can be tailored by average Ba/Sr ratio and structures. When the average Ba/Sr ratio is unchanged, the structure with smaller lattice parameter of middle layer than that of top/bottom layer can achieve larger tunability resulting from its smaller compressive misfit strain, which has been qualitatively characterized by X-ray diffraction and Raman spectra. Especially, the largest tunability reaches 30 % under the electric field of 300 kV cm by locating BaSrTiO layer in the middle and BaSrTiO layers at ends. Furthermore, the experimental dielectric constants and tunabilities are in good agreement with the calculated data, instructing that the dielectric properties of BST thin films with unchanged Ba/Sr ratio can be tailored by changing the structure to adjust the lattice misfit strain of each uniform layer. This implies that multilayer BST thin films also can be designed by phenomenological theory. [ABSTRACT FROM AUTHOR]

We describe a lattice Boltzmann (LB) method for simulating water isotope fractionation during diffusion-limited ice crystal growth by vapor deposition from water-oversaturated air. These conditions apply to the growth of snow crystals in clouds where the vapor composition is controlled by the presence of both ice crystals and water droplets. Modeling of water condensation with the LB method has the advantage of allowing concentration fields to evolve based on local conditions so that the controls on grain shapes of the condensed phase can be studied simultaneously with the controls on isotopic composition and growth rate. Water isotope fractionation during snow crystal growth involves kinetic effects due to diffusion of water vapor in air, which requires careful consideration of the boundary conditions at the ice-vapor interface. The boundary condition is relatively simple for water isotopes because the molecular exchange rate for water at the interface is large compared to the crystal growth rate. Our results for the bulk crystal isotopic composition are consistent with simpler models using analytical solutions for radial geometry. However, the model results are sufficiently different for oxygen isotopes that they could affect the interpretation of D-excess values of snow and ice. The extent of vapor oversaturation plays a major role in determining the water isotope fractionation as well as the degree of dendritic growth. Departures from isotopic equilibrium increase at colder temperatures as diffusivity decreases. Dendritic crystals are isotopically heterogeneous. Isotopic variations within individual snow crystals could yield information on the microphysics of ice condensation as well as on the accommodation or sticking coefficient of water associated with vapor deposition. Our results are ultimately a first step in implementing LB models for kinetically controlled condensation or precipitation reactions, but needs to be extended also to cases where the molecular exchange rate is comparable to the crystal growth rate. This approach could also be applicable to aerosol chemical evolution. [ABSTRACT FROM AUTHOR]

Sepsis is a critical condition affecting patients worldwide. Systemic inflammatory response syndrome in sepsis contributes to organ dysfunction and mortality. The oXiris is a recently developed continuous renal replacement therapy (CRRT) hemofilter indicated for the adsorption of cytokines from the bloodstream. In our study, in a septic child, CRRT with three filters, including the oXiris hemofilter, resulted in a downregulation of inflammatory biomarkers and a reduction of vasopressors. Herein, we described the first report of such usage in septic children. [ABSTRACT FROM AUTHOR]

This paper investigates the parameter estimation of Hammerstein–Wiener systems whose linear subsystems are observable state-space models. The particle swarm optimization (PSO) and gravitational search (GSA) algorithms are combined to derive a novel method for identifying the discussed systems. To improve the optimization ability, some improvements are employed, including adding the oscillating exponential decay inertia weight and fuzzy membership in PSO (OFPSO) and introducing the chaotic optimization mechanism to GSA (CGSA). Thus, the combination of OFPSO and CGSA (OFPSO-CGSA) method is proposed. Its principle is to utilize coordinated behaviors of the speed in the OFPSO algorithm and the acceleration in the CGSA algorithm to update the particle position. Moreover, the convergence analysis proves that the OFPSO-CGSA algorithm converges to the global solution with probability one. Two simulations of the Hammerstein–Wiener nonlinear systems with two-dimensional and three-dimensional linear state space subsystems verify that the algorithms are effective, and OFPSO-CGSA has the best performance considering the convergence speed and identification accuracy in the algorithm comparison. [ABSTRACT FROM AUTHOR]

This paper investigated aqueous chemistry for two geothermal spring groups responsive and sensitive to flow fluctuations induced by earthquakes. Quake monitorings are favored for their being in residential areas with well-preserved natural flow systems in Xinyi City's Xijiang Hot Springs and Fengshun County's Shihu Hot Spring. The hot springs are typical in temperatures and flow rates in southern China's Guangdong Province. Physical and chemical conditions deep down in the heat sources are important constraints on earthquake, fluid flow, reactive solute transport and heat transfer, but remain challenging to address via field observations and numerical experiments. In this paper, we made daily and annual observations on flow rates, temperature, and/or aqueous chemistry. We employed strontium isotopes as tracers for the water sources, equilibrium phase diagram for K-feldspar and albite stability, and Na-K-Mg diagram for heat reservoir temperatures. The abundant sulfite content in Xijiang Hot Springs is discussed. Our main finding are that the deep fault springs are characterized by low reduction-oxidation potential at around −200- −150 mV and relatively large daily flow variations. The results provide scientific background features on the field sites regarding earthquake monitoring and predictions and geothermal reservoir. [ABSTRACT FROM AUTHOR]

This paper investigates the parameter estimation of errors-in-variables Wiener (EIV-W) nonlinear systems. In such nonlinear systems, both input and output contain interference noises, and some intermediate processes are also interfered by noises. The hierarchical technology is applied to decompose the whole system into two subsystems firstly. For the linear subsystem, in order to obtain unbiased estimates of model parameters, a bias compensation method is introduced. Then, the bias-compensated least squares (BLS) algorithm is proposed. For the nonlinear subsystem, on the basis of particle swarm optimisation (PSO), the fuzzy control technology is added to improve the ability of jumping out of the local optimum. Thus, a bias-compensated least squares and fuzzy PSO based hierarchical (BLS-FPSO-H) method is derived at last. In simulation, a numerical example and a case study about the carbon fibre stretching process are implemented. Results indicate that the BLS-FPSO-H algorithm can effectively identify EIV-W nonlinear systems, the convergence speed and identification accuracy are greatly improved than the basic PSO method and some other PSO variants. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis and catalytic evaluation of palladium complexes containing NCN Pincer ligand is reported. The pincer palladium complexes as (pre)catalyst showed efficient catalytic activity for the C–H arylation of N-substituted indoles, allowing the synthesis of 2-arylindoles with moderate to good yields and excellent regioselectivities. [Copyright &y& Elsevier]

SUMMARY This paper discusses the exponential stability and stabilization for nonlinear descriptor systems with discrete and distributed delays. In terms of the Lyapunov method, the exponential stability of the slow subsystem is firstly obtained. Then, a new homotopy-based approach is proposed to investigate the exponential stability of the fast subsystem. By an estimate of the weighted matrix norm for a nonlinear mapping, the exponential stability of the fast subsystem and thus delay-dependent sufficient conditions for the exponential stability of the systems are obtained. In addition, a state feedback controller is designed for the stabilization of the nonlinear descriptor systems. Finally, the effectiveness of the proposed approach is illustrated by numerical examples. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper presents a new approach to the output feedback control problem of master-slave synchronization of time-delay chaotic Lur'e systems with sector and slope restricted nonlinearities under communication constraints. The communication constraints involve measurement quantization and signal transmission delay. By constructing an appropriate Lyapunov functional with the idea of a discretized Lyapunov-Krasovskii functional method and utilizing the sector bound of the logarithmic quantizer, a delay-dependent synchronization criterion is derived. The desired synchronization controller can be obtained by solving a set of linear matrix inequalities. Finally, numerical simulations for Chua's circuit are proposed to show the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the model-based networked control is addressed for a class of singularly perturbed control systems with nonlinear uncertainties. An approximate linear slow and fast control system of the plant, which can be obtained by omitting the nonlinear uncertainties, are used as a model to estimate the state behavior of the plant between transmission times. The stability of model-based networked control systems is investigated under the assumption that the controller/actuator is updated with the sensor information at constant time intervals. It is shown that there exists the allowable upper bound of the singular perturbation parameter such that the model-based networked control system is globally exponentially stable. [Copyright &y& Elsevier]

Abstract: This paper addresses the existence and uniqueness of a solution and stability for Lipschitz discrete-time descriptor systems. By means of the fixed point principle, a criterion is presented via a matrix inequality, and the criterion guarantees the existence and uniqueness of a solution. In addition, a sufficient condition is also presented to ensure that the solution exists for any compatible initial condition and the system is globally exponentially stable simultaneously. It is shown that the criterion presented in this paper is easy to verify and independent of the choices of decomposition matrices for the given system. Finally, the approach is illustrated by a numerical example. [Copyright &y& Elsevier]

Summary: This paper presents modeling analyses of long term infiltration and tracer tests in fractured tuffs at Yucca Mountain, NV, USA. The experiments were conducted on a 20m thick tuff section in a flyover formed by two exploratory tunnels. The infiltration test last for 870days. Both measured infiltration and seepage show significant temporal and spatial variations. The tracer test used inorganic tracers (I−, Br−, F−) and organic tracers (fluorobenzoic acids) released 559days after the infiltration test started. Leaching from dry salts from fracture walls was found to have affected tracer breakthroughs. The unsaturated flow was evaluated by optimizing 45 parameter values in a three-dimensional model, which accounts for fracture–matrix interaction and heterogeneous hydraulic properties in a column-based scheme. The field data are valuable asset to evaluate the modeling approaches for fractured rocks and the relative importance of the matrix diffusion process. Results show that matrix diffusion is an important process for transport, and that effective matrix-diffusion coefficients at the field-scale are larger than those at the laboratory-scale for the solutes. [Copyright &y& Elsevier]

Abstract: This paper addresses the state estimation and stabilization for linear discrete-time descriptor systems. It is assumed that the estimator and controller can only receive the transmitted sequence of finite coded signals via a limited digital communication channel. Both coder–decoder and coder–decoder–controller procedures are proposed, in which a compensation term is introduced to meet the compatible requirement. In addition, an effective method for selecting the compensation term is presented. Detection and stabilization conditions in terms of linear matrix inequality are obtained. Finally, an example is given to illustrate the effectiveness of design procedures. [Copyright &y& Elsevier]

Abstract: Metal oxide and oxyhydroxide nanoparticles are important components of natural aqueous systems and have application in photocatalysis. Uncoated (oxyhydr)oxide nanoparticles can form charge-stabilized colloids in water, but the precise regimes of dispersion and aggregation have been determined for very few nanomaterials. We studied the colloidal behavior of ∼6 nm nanoparticles of iron oxyhydroxide (FeOOH), a common natural nanoscale colloid, and found that these nanoparticles formed stable suspended clusters under a range of aqueous conditions. Light and X-ray scattering methods show that suspended fractal nanoclusters are formed between pH 5 and 6.6 with well-defined maximum diameters that can be varied from 25 nm to approximately 1000 nm. The nanoclusters retain a very high surface area, and persist in suspension for at least 10 weeks in solution. The process is partially reversible because optically transparent suspensions are regained when nanoparticles that aggregated and settled at pH >7 are adjusted to pH 4 without stirring. However, completely redispersed nanoparticles are not obtained even after one month. Because nanocluster formation is controlled predominantly by surface charge, we anticipate that many metal oxide and other inorganic nanoparticles will exhibit equivalent cluster-forming behavior. Our results indicate that natural nanoparticles could form stable nanoclusters in groundwater that are likely to be highly mobile, with implications for the long-range transport of surface sorbed contaminants. [Copyright &y& Elsevier]

Abstract: Global asymptotic stabilization for a class of singular bilinear systems is first studied in this paper. New approaches are developed by means of the LaSalle invariant principle for nonlinear systems. A new set of sufficient condition is first derived via the continuous static state feedback, the feedback not only guarantees the existence of solution but also the global asymptotical stabilization for the closed loop system. [Copyright &y& Elsevier]

This paper discusses a robust stabilization problem for a class of multi-input and multi-output (MIMO) discrete-time non-linear systems with both state and control inputs containing non-linear perturbations. The problem is solved via static output feedback and dynamic output feedback, respectively. A unified approach is used to cast the problem into a convex optimization involving linear matrix inequalities (LMI), all the controllers can robustly stabilize the systems and maximize the bound on the non-linear perturbations. This paper also extends the output feedback centralized design approach to a class of discrete-time MIMO non-linear decentralized systems, both robust static and dynamic output feedback controllers are obtained. [ABSTRACT FROM AUTHOR]

The article presents the authors' comments on Chinese contribution to global health as of August 30, 2014. Topics include China's global health development, China's rural and urban health-care network, and health-care technologies' use. Attention is paid to the China-Association of Southeast Asian Nations (ASEAN) Public Health Fund, the Asia-Pacific Economic Cooperation (APEC), and the first Brazil, Russia, India, China, and South Africa (BRICS) Health Ministers' meeting in Beijing, China.

Presents a comprehensive modeling framework for simulating the natural attenuation of fuel-hydrocarbons using the RT3D computer code. Contamination of ground water in the United States; Bioremediation technologies for treatment of contaminated ground water sites; Natural attenuation as treatment technology for managing organic solute plumes.

Febrile infection–related epilepsy syndrome (FIRES) is a devastating epileptic encephalopathy with limited treatment options and unclear etiology. Vagus nerve stimulation (VNS) is an FDA-approved therapy for refractory epilepsy that has been shown to decrease the frequency and severity of seizures. There is a growing interest in alternate non-pharmaceutical therapies for managing super-refractory status epilepticus (SRSE). We present a 29-month-old case, diagnosed with FIRES, whose seizures were successfully controlled by utilization of VNS after ineffective response to intensive pharmacotherapy and ketogenic diet treatment. The VNS was planted after 14 days of refractory seizure activity with a following rapid parameter titration for 42 days without evident side effect, which finally controlled the seizure in the acute phase. VNS may be a potential candidate for the treatment of SRSE in FIRES. [ABSTRACT FROM AUTHOR]

Hydrodeoxygenation (HDO) for upgrading biomass usually requires high temperature and high H2 pressure. Herein, g-C3N4-supported Pd–Au bimetallic nanoparticles are reported as an efficient catalyst for the HDO of vanillin, a typical biomass-derived compound, and some other aromatic aldehydes. With the catalyst and formic acid as the hydrogen donor, the reaction occurs at room temperature and under atmospheric air, and a satisfactory yield of the desired product was achieved within 1 h. A two-phase solvent of H2O and EA was used, and the catalyst could be reused at least 5 times. The superior performance of PdAu/g-C3N4 compared to monometallic catalysts could be mainly ascribed to the synergistic catalysis inside the catalyst, which was explored via characterization analysis. [ABSTRACT FROM AUTHOR]

In this study, we devised a diagnostic platform harnessing a combination of recombinase polymerase amplification (RPA) and the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a system. Notably, this platform obviates the need for intricate equipment and finds utility in diverse settings. Two result display methods were incorporated in this investigation: the RPA-Cas12a-fluorescence method and the RPA-Cas12a-LFS (lateral flow strip). Upon validation, both display platforms exhibited no instances of cross-reactivity, with seven additional types of fungal pathogens responsible for respiratory infections. The established detection limit was ascertained to be as low as 102 copies/µL. In comparison to fluorescence quantitative PCR, the platform demonstrated a sensitivity of 96.7%, a specificity of 100%, and a consistency rate of 98.0%.This platform provides expeditious, precise, and on-site detection capabilities, thereby rendering it a pivotal diagnostic instrument amenable for deployment in primary healthcare facilities and point-of-care settings. [ABSTRACT FROM AUTHOR]

Aims/Introduction: Diabetic cardiomyopathy is a type of myocardial disease. It causes left ventricular hypertrophy, followed by diastolic and systolic dysfunction, eventually leading to congestive heart failure. However, the underlying mechanism still requires further elucidation. Materials and Methods: A high‐glucose zebrafish model was constructed by administering streptozocin intraperitoneally to enhance the development of cardiomyopathy and then treated with adenosine monophosphate‐activated protein kinase (AMPK) activator. Cardiac structure and function, and protein and gene expression were then analyzed. Cardiomyocytes (CMs) culture in vitro using lentivirus were used for detection of AMPK, p53 and Krüppel‐like factor 2a (klf2a) gene expression. Results: In the hyperglycemia group, electrocardiogram findings showed arrhythmia, echocardiography results showed heart enlargement and dysfunction, and many differences, such as increased apoptosis and myocardial fiber loss, were observed. The phospho‐AMPK and klf2a expression were downregulated, and p53 expression was upregulated. Activation of phospho‐AMPK reduced p53 and increased klf2a expression, alleviated apoptosis in CMs and improved cardiac function in the hyperglycemic zebrafish. In vitro knockdown system of AMPK, p53 and klf2a using lentivirus illustrated an increased p53 expression and decreased klf2a expression in CMs by inhibiting AMPK. Repression of p53 and upregulation of klf2a expression were observed, but no changes in the expression of AMPK and its phosphorylated type. Conclusions: In the model of streptozocin‐induced hyperglycemia zebrafish, the reduction of phosphorylated AMPK increased p53, which led to KLF2a decrease to facilitate apoptosis of CMs, inducing the cardiac remodeling and cardiac dysfunction. These results can be reversed by AMPK activator, which means the AMPK–p53–klf2a pathway might be a potential target for diabetic cardiomyopathy intervention. [ABSTRACT FROM AUTHOR]

Aims: Status epilepticus (SE) is the most common neurological emergency in pediatric patients. This study aimed to screen for prognostic biomarkers of SE in the cerebrospinal fluid (CSF) using metabolomics. Methods: Ultra‐performance liquid chromatography quadrupole time‐of‐flight tandem mass spectrometry (UPLC‐QTOF‐MS) was conducted to identify prognostic biomarkers in CSF metabolomics by comparing the poor outcome group (N = 13) with the good outcome group (N = 15) of children with SE. Differentially expressed metabolites were identified using Mann–Whitney U test corrected by Benjamini‐Hochberg and partial least squares discriminant analysis (PLS‐DA). Results: The PLS‐DA model identified and validated significant metabolic differences between the poor and good outcome groups of children with SE (PLS‐DA with R2Y = 0.992 and Q2 = 0.798). A total of 49 prognosis‐related metabolites were identified. Of these metabolites, 20 including glutamyl‐glutamine, 3‐iodothyronamine, and L‐fucose had an area under the curve (AUC) ≥ 80% in prognostic prediction of SE. The logistic regression model combining glutamyl‐glutamine and 3‐iodothyronamine produced an AUC value of 0.976, with a sensitivity of 0.863 and specificity of 0.956. Pathway analysis revealed that dysregulation of the citrate cycle (TCA) and arginine biosynthesis may contribute to poor SE prognosis. Conclusions: This study highlighted the prognosis‐related metabolomic disturbances in the CSF of children with SE and identified potential prognostic biomarkers. A prognostic prediction model combining glutamyl‐glutamine and 3‐iodothyronamine with high predictive value was established. [ABSTRACT FROM AUTHOR]

Background. The purpose of this study was to evaluate the association between the non-high-density lipoprotein cholesterol (non-HDL-C) to high-density lipoprotein cholesterol (HDL-C) ratio and the risk of coronary artery disease (CAD). We also explored the potential role of non-HDL-C/HDL-C in the prognosis of CAD. Methods. We analyzed 930 consecutive patients with chest discomfort who underwent coronary angiography. Of these, 680 were diagnosed with CAD; the remaining 250 patients were normal. Multivariate logistic regression and receiver operating characteristic (ROC) curves were employed to evaluate the association between non-HDL-C/HDL-C and CAD. The effect of non-HDL-C/HDL-C on the progression of major adverse cardiovascular events (MACEs) was also explored. Results. Increased non-HDL-C/HDL-C was associated with an increased risk of CAD (OR: 1.291; 95% CI: 1.039-1.561; P = 0.013). The results of stratified analyses by CAD subtype showed a correlation between high non-HDL-C/HDL-C and increased risk of acute coronary syndrome (OR: 1.661; 95% CI: 1.259-2.207; P < 0.001), high Gensini score (OR: 1.408; 95% CI: 1.021-1.935; P = 0.039), and multivessel disease (OR: 1.487; 95% CI: 1.128-1.992; P = 0.007). Moreover, the areas under the ROC for the predictive value of non-HDL-C/HDL-C for CAD, acute coronary syndrome, high Gensini score, and multivessel disease were 0.604, 0.658, 0.642, and 0.636, respectively. Non-HDL-C/HDL-C in CAD patients was significantly correlated with the risk of long-term MACEs (P = 0.004). Conclusions. The findings of this study indicated that non-HDL-C/HDL-C plays an important role in the risk and progression of CAD. These findings need verification by further large-scale prospective studies. [ABSTRACT FROM AUTHOR]

Objectives: Continuous renal replacement therapy becomes available utilization for pediatric critically ill, but the impact of mortality rate in severe sepsis remains no consistent conclusion. The aim of the study is to assess the effect of continuous renal replacement therapy in pediatric patients with severe sepsis and the impact this therapy may have on their mortality.Design: Propensity score-matched cohort study analyzing data prospectively collected by the PICUs over 2 years (2016-2018).Setting: Four PICUs of tertiary university children's hospital in China.Patients: The consecutive patients with severe sepsis admitted to study PICUs were enrolled from July 2016 to June 2018.Interventions: The patients were divided into the continuous renal replacement therapy group and the conventional (noncontinuous renal replacement therapy) group.Measurements and Main Results: A total of 324 patients with severe sepsis were enrolled. The hospital mortality rate was 35.6% (64/180) in the continuous renal replacement therapy group and 47.9% (69/144) in the noncontinuous renal replacement therapy group. After propensity score adjustment, the hospital mortality rate was 21.3% (29/136) in the continuous renal replacement therapy group and 32.4% (44/136) in the noncontinuous renal replacement therapy group. In subgroup analysis, the relative risk of dying was 0.447 (95% CI, 0.208-0.961) only in patients complicated by acute respiratory distress syndrome (p = 0.037), but not in patients with shock, acute kidney injury, acute liver dysfunction, encephalopathy, and fluid overload greater than 10%. The mean duration of continuous renal replacement therapy was 45 hours (26-83 hr) with an ultrafiltration rate of 50 mL/kg/hr. The level of interleukin-6 was decreased, and the percent of natural killer cells (%) was improved in the continuous renal replacement therapy group compared with the noncontinuous renal replacement therapy group. Furthermore, continuous renal replacement therapy was an independently significant risk factor for hospital mortality in pediatric patients with severe sepsis, and the interval between continuous renal replacement therapy initiation and PICU admission was an independent risk factor for hospital mortality in patients receiving continuous renal replacement therapy.Conclusions: Continuous renal replacement therapy with an ultrafiltration rate of 50 mL/kg/hr decreases hospital mortality rate in pediatric severe sepsis, especially in patients with acute respiratory distress syndrome. [ABSTRACT FROM AUTHOR]

A simple homogeneous catalyst system composed of commercially available [IrCl(cod)]2 and 1,10-phenanthroline is used for the selective transfer hydrogenation of nitroarenes to anilines. [ABSTRACT FROM AUTHOR]

An atom-economic, environmentally benign method for the oxidative cross-coupling of isochroman derivatives with thiol derivatives is examined. [ABSTRACT FROM AUTHOR]

Herein, we describe a photo-responsive organogel using low molecular mass gelators (LMOGs) of stilbenedicarboxylic acid (St) and octadecylamine (NC 18). Organogels could be obtained by the mixture of St and NC 18 in a variety of organic solvents, which was in the formation of ion pairs via electrostatic interaction. The phase transition temperature of the St(NC 18) 2 gel increased with the increase of the gel agent concentration, which reached a constant value of 369 K at gel agent concentration of 90 mmol/L. The organogels could be destroyed by UV irradiation, originating from the photo-responsive characteristics of the stilbene group. Compared with the traditional responsive LMOGs, the St(NC 18) 2 gel system is composed of readily available compounds. The organogel will have a wider range of applications in the development of the smart materials for sensors, recognition, and separation. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Carbapenem-resistant gram-negative bacilli (CR-GNB) have been increasingly reported in China. However, dynamic monitoring data on molecular epidemiology of CR-GNB are limited in pediatric patients. Results: 300 CR-GNB isolates (200 Carbapenem-resistant K. pneumoniae (CRKP), 50 carbapenem-resistant A.baumannii (CRAB) and 50 carbapenem-resistant P. aeruginosa (CRPA)) were investigated. The predominant carbapenemase gene was blaNDM−1 (73%) and blaKPC−2 (65%) in neonates and non-neonates. Meanwhile, the predominant STs were ST11 (54%) in neonates and ST17 (27.0%) and ST278 (20.0%) in non-neonates. Notably, a shift in the dominant sequence type of CRKP infections from ST17 /ST278-NDM-1 to ST11-KPC-2 was observed during the years 2017–2021 and KPC-KP showed relatively higher resistance to aminoglycosides and quinolones than NDM-KP.BlaOXA−23 was isolated from all the CRAB isolates while only one isolate expressing blaBIC and 2 isolates expressing blaVIM−2 were found in CRPA isolates. ST195 (22.0%) and ST244 (24.0%) were the most common in CRAB and CRPA isolates and all the STs of CRAB belonged to CC92 while CRPA presents ST types with diversity distribution. Conclusion: CRKP showed different molecular phenotypes in neonates and non-neonates and was changing dynamically and high-risk clone of ST11 KPC-KP should be paid more attention. Most CRKP and CRAB strains shared the same CCs, suggesting that intrahospital transmission may occur, and large-scale screening and more effective measures are urgently needed. [ABSTRACT FROM AUTHOR]

Ortho-brom benzyl alcohols are also applicable in these reactions with slightly lower yields. [ABSTRACT FROM AUTHOR]

This paper considers the event-triggered H ∞ filtering problem for continuous-time switched linear systems. It is assumed that only the information of system output and switching signal is available to the filter at each event-triggered sampling instant. Based on a mode dependent event-triggered sampling scheme, the filtering error system is modeled as a switched system with augmented switching signal. Then, by the average dwell time technique and multiple Lyapunov function method, a new sufficient condition is obtained such that the filtering error system is exponentially asymptotically stable and satisfies the weighted H ∞ performance. The design method for the filter and event-triggered parameters is formulated by solving a set of linear matrix inequalities. Finally, the effectiveness of the proposed approach is illustrated by two numerical examples. [ABSTRACT FROM AUTHOR]

We developed a clay pore water (CPW) isotopic method for tracing paleoenvironments characterized by sporopollens. The thick clayey layers have the advantage of preserving pore water regardless of whether the water is inherent in the clayey layers or not. Therefore, the clayey layers are a suitable target from which paleoenvironmental information can be extracted. Sediment sporopollens as well as CPW deuterium and oxygen isotopes were investigated in drilling cores obtained from a 130-m borehole at a field site in Hengshui in the North China Plain. Our interpretation of δ 18 O in CPW was consistent with sporopollens climate indices, indicating that CPW was an effective proxy for obtaining paleoenvironmental information. Sporopollens species were abundant in the cores, but the quantity of each species was low. Furthermore, mean annual temperature and precipitation curves were established using a pollen–climatic response surface model. The results indicated two warm-humid periods (5.2–0 m, 22.6–11 m) and one cold-dry period (8.8–6.4 m) in the Holocene as well as two warm-humid periods (90.6–83 m, 110.6–108.2 m) and three cold-dry periods (approximately 40 m, 66.4–56.8 m, approximately 100 m) in the Late Pleistocene. Data derived from the sporopollens and CPW cumulatively elucidate the environmental change in Northern China. [ABSTRACT FROM AUTHOR]

This method uses thiourea as an odorless sulfur source and proceeds generally with high Z-selectivity. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Palladium (II)-Catalyzed Oxidative ortho-Arylation of 2-Phenylpyridines" by researcher J. Feng and others in the 2013 issue of the periodical "Synlett."

Background: The concept of acute kidney injury (AKI) substages has been recommended to better phenotype AKI and identify high-risk patient groups and therefore improve the diagnostic accuracy of AKI. However, there remains a gap between the recommendation and the clinical application. The study aimed to explore the incidence of AKI substages based on a sensitive AKI biomarker of urinary cystatin C (uCysC), and to determine whether AKI substages were relevant with respect to outcome in critically ill children. Results: The multicenter cohort study enrolled 793 children in pediatric intensive care unit (PICU) of four tertiary hospitals in China. Children were classified as non-AKI, sub-AKI and AKI substages A and B according to uCysC level at PICU admission. Sub-AKI was defined by admission uCysC level ≥ 1.26 mg/g uCr in children not meeting the KDIGO criteria of AKI. In children who fulfilled KDIGO criteria, those with uCysC < 1.26 was defined as AKI substage A, and with ≥ 1.26 defined as AKI substage B. The associations of AKI substages with 30-day PICU mortality were assessed. 15.6% (124/793) of patients met the definition of sub-AKI. Of 180 (22.7%) patients with AKI, 90 (50%) had uCysC-positive AKI substage B and were more likely to have classical AKI stage 3, compared to substage A. Compared to non-AKI, sub-AKI and AKI substages A and B were risk factors significantly associated with mortality, and the association of sub-AKI (adjusted hazard ratio HR = 2.42) and AKI substage B (adjusted HR = 2.83) with mortality remained significant after adjustment for confounders. Moreover, AKI substage B had increased risks of death as compared with sub-AKI (HR = 3.10) and AKI substage A (HR = 3.19). Conclusions: Sub-AKI defined/based on uCysC occurred in 20.2% of patients without AKI and was associated with a risk of death close to patients with AKI substage A. Urinary CysC-positive AKI substage B occurred in 50% of AKI patients and was more likely to have classical AKI stage 3 and was associated with the highest risk of mortality. [ABSTRACT FROM AUTHOR]