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In this paper, we study a three-dimensional full hydrodynamic model in a bounded domain with insulating and adiabatic boundary. The model takes the form of nonisentropic Euler-Poisson system and incorporates recombination/generation terms, describing the bipolar transport of hot carriers in semiconductor optoelectronic devices. Of particular concern are the existence, uniqueness and exponential stability of thermal equilibrium states to the model, since these mathematical results are rendered useful in numerical simulation and physical theory of semiconductors. They are rigorously proved by the perturbation argument and energy method. [ABSTRACT FROM AUTHOR]

Using a genetic algorithm together with DFT computations, the stable isomers of Lin+1Fn (n = 2 ~ 17) are obtained. It is found that the Li3F2 is a planar structure, and starting at n = 3, Lin+1Fn adopt three-dimensional configurations with a terminal Li atom or vacancy of F atom. As the cluster sizes increase, the geometries of Lin+1Fn develop, first with cube-like and tubular structures, then forming cage-like arrangements, and eventually favoring rock-salt configurations. The Lin+1Fn (n = 3, 5, 8, 11, 13 and 15) are especially stable and magic number clusters. Low ionization potentials are acquired for Lin+1Fn due to the weakly bonded odd electrons of Li atoms. Particularly, the AIP/VIP for Li14F13 and Li17F16 are only 2.68/2.75 eV and 2.77/2.97 eV, respectively, which indicate that they can be looked as superalkali clusters. Meanwhile, the particularly large hyperpolarizabilities (3237157.14 a.u. and 716489.10 a.u.) for these two isomers are also obtained. According to the electronic structure analysis, Li atoms donate their 2s electrons to the 2p orbitals of F atoms, forming Li–F ionic bonds. Additionally, the spectral properties and the reactivities for the magic number clusters are further investigated. [ABSTRACT FROM AUTHOR]

Surfactant‐free microemulsions (SFMEs) cleaning technology can effectively separate and recover petroleum pollutants from oil‐based drilling cuttings (OBDCs). The identification of the molecular composition of OBDCs is helpful to accurately grasp the conversion mechanism of organic matter. Therefore, the understanding of the mechanism of petroleum removal at the microscopic molecular level in the cleaning process needs to be further studied. The conversion mechanism of organic matter during the use of SFMEs to clean OBDCs was investigated by positive ion atmospheric pressure photoionization Fourier transform ion cyclotron resonance mass spectrometry (+APPI FT‐ICR MS). The results show that the SFMEs cleaning technology can separate and recover CH and CHO organic matter in OBDCs, but there is still a small amount of organic matter with high molecular weight and unsaturated degree in OBDCs that has not been separated. The majority of this organic matter is CH, accounting for 91 %, and it is mainly polycyclic aromatic hydrocarbons. A total of 255 kinds of organic matter in 110# industrial white oil were detected in the recovered oil after treatment, accounting for more than 99 % of the total, which has a certain recoverable value. This study can provide a theoretical reference for the efficient degradation of OBDCs. [ABSTRACT FROM AUTHOR]

Mo13 is a magic number cluster of Mon and can effectively activate N2 in ammonia synthesis, but its ground-state structure is not determined. The possible stable isomers of Mo13 are obtained by using global searching method (genetic algorithm) and further optimized at the level of BP86/def2-TZVP. The results indicate that Mo13 prefers to adopt open or layer-type structures due to the stronger 4d-5 s orbital hybridization. The most stable structure of Mo13 is a seriously deformed icosahedron and it is nearly degenerated in energies with the isomer of cage-like one. Both these two isomers are with high stabilities, and thus the electronic structures, bonding characters, spectral properties, reactive activities and the external filed response for these two isomers are systematically explored. This work provides many important information for distinguishing these two isomers. [ABSTRACT FROM AUTHOR]

This paper is concerned with the zero-relaxation limits for periodic smooth solutions of the non-isentropic Euler–Maxwell system in a three-dimensional torus prescribing the well/ill-prepared initial data. The non-isentropic Euler–Maxwell system can be reduced to a quasi-linear symmetric hyperbolic system of one order. By observing a special structure of the non-isentropic Euler–Maxwell system, we are able to decouple the system and develop a technique to achieve the a priori H s estimates, which guarantees the limit for the non-isentropic Euler–Maxwell system as the relaxation time τ → 0 . We realize that the convergence rate of the temperature is the same as the other unknowns in the L ∞ (0 , T 1 ; H s) , but the convergence rate of the temperature is slower than the velocity in L 2 (0 , T 1 ; H s) . The zero-relaxation limit presented here is the transport equation coupled with the drift–diffusion system. However, the limit of the isentropic Euler–Maxwell system is the classical drift–diffusion system. This shows the essential difference between the isentropic and non-isentropic Euler–Maxwell systems. [ABSTRACT FROM AUTHOR]

Background • Despite growing interest in nutrition as a behavioral intervention to improve cognitive health in clinical populations, many providers find it challenging to provide specific nutritional recommendations. We aimed to review and synthesize current empirical research on this topic and provide considerations for healthcare providers working with adults who wish to optimize their cognition via dietary improvements. Methods • We performed a narrative review of research published between January 2009 and May 2021 on 5 popular dietary interventions: the Mediterranean diet, Dietary Approaches to Stop Hypertension (DASH), the Mediterranean-DASH Intervention Diet for Neurodegenerative Delay (MIND), the ketogenic diet and intermittent fasting. Results and Conclusions • Of the 5 dietary interventions, the Mediterranean diet has been the most extensively investigated, and there is evidence supporting its cognitive benefits. However, operationalization of the Mediterranean diet varies across studies, rendering the results inconclusive. The DASH diet and the MIND diet have stronger operationalization and showed evidence of cognitive benefits. More longitudinal studies and/or randomized clinical trials should be conducted on these 2 relatively new interventions. Finally, there is limited research with human participants regarding the ketogenic diet and intermittent fasting, which are found to be cognitively protective within stringent parameters. Definitions for these 5 dietary patterns and practice tips and recommendations are provided. [ABSTRACT FROM AUTHOR]

Cocrystal is considered an effective way to improve the performance of energetic materials and might be used to solve the contradiction between the energy density and safety. In this paper, hexanitrohexaazaisowurtzitane (CL‐20) and 4amino‐3,7‐dinitro‐[1,2,4]triazolo[5,1‐c] [1,2,4]triazine (TTX) are modeled, and the cocrystal structure of hexanitrohexaazaisowurtzitane/4‐Amino‐3,7‐dinitro‐ [1,2,4]triazolo[5,1‐c] [1,2,4]triazine (CL‐20/TTX) is simulated by molecular dynamics. Based on the model equilibrium, this paper demonstrates a strong intermolecular interaction between CL‐20 and TTX with the generation of hydrogen bonds by simulating the binding energy, radial distribution function (RDF) and X‐ray powder diffraction (XRD) of CL‐20/TTX. All the above characterizations could prove that a new type of cocrystal structure may exist between CL‐20 and TTX, i. e. CL‐20/TTX is a new type of cocrystal material. The cohesive energy density (CED), trigger bond length and mechanical properties between the two are also simulated in this paper, and it is concluded that this cocrystal structure could greatly improve not only the high sensitivity defects of CL‐20, but also the mechanical properties of CL‐20 and TTX. The simulation of the CL‐20/TTX cocrystal structure in this paper could provide a reference for the screening of CL‐20 cocrystal and provide guidance for future experimental preparation. [ABSTRACT FROM AUTHOR]

Thrixspermum taeniophyllum is described as a new orchid species from Wenchuan County, Sichuan Province of southwest China. It is morphologically similar to T. japonicum, but it differs from the latter in having branched stems, slightly fleshy strapshaped leaves, longer inflorescences with 3–6 flowers and a capitate gynandrium with a lip-shaped mouth opening. Its species status is also supported by molecular phylogenetic analyses, based on nuclear ribosome internal transcribed spacer (nrITS) and three chloroplast DNA fragments (matK, psbA-trnH and trnL-F), which showed distinct systematic boundaries from the most morphologically similar T. japonicum and their morphological relatives T. saruwatarii and T. pygmaeum. [ABSTRACT FROM AUTHOR]

A unique rotary kite turbine designed with tensile rotary power transmission (TRPT) is introduced in this work. Power extraction, power transmission and the ground station are modelled in a modular framework. The TRPT system is the key component of power transmission, for which three models with different levels of complexity are proposed. The first representation is based on the stationary state of the system, in which the external and internal torques of a TRPT section are in equilibrium, referred to as the steady-state TRPT model. The second representation is a simplified spring-disc model for dynamic TRPT, and the third one is a multi-spring model with higher degrees of freedom and more flexibility in describing TRPT dynamics. To assess the torque loss on TRPT, a simple tether drag model is written for the steady-state TRPT, followed by an improved tether drag model for the dynamic TRPT. This modular framework allows for multiple versions of the rotor, tether aerodynamics and TRPT representations. The developed models are validated by laboratory and field-testing experimental data, simulated over a range of modelling options. Model-based analysis are performed on TRPT design, rotor design and tether drag to understand any limitations and crucial design drivers. Improved designs are explored through multi-parameter optimisation based on steady-state analysis. [ABSTRACT FROM AUTHOR]

To investigate the role of tracheal wall injury in the development of benign airway stenosis in rabbits. Prospective study. We injured the tracheal walls of 28 New Zealand white rabbits using four different methods. Experimental group: Group A (n = 7, mild injury of tracheal mucosa by ordinary brush under bronchoscopy); Group B (n = 7, severe injury of tracheal mucosa by nylon brush under tracheotomy); Group C (n = 7, tracheal cartilage was injured by vascular clamp after tracheotomy); Group D (n = 7, the tracheal cartilage was injured with vascular forceps and the tracheal mucosa was injured with a nylon brush after tracheotomy). Bronchoscopy was performed on each experimental rabbit at 1, 2, 3 and 4 weeks after operation. High-resolution computed tomography (HRCT) and endobronchial optical coherence tomography (EB-OCT) were performed at 4 weeks, and the rabbits were sacrificed after the examination. Their gross and histological findings were comparatively determined whether the experimental rabbit stenosis was established. No airway stenosis was observed in group A. In group B, 28.57% of experimental rabbits developed tracheal stenosis (granulation tissue proliferation was observed in rabbits No. 2 and No. 6 at 1, 2 and 3 weeks after operation, and the tracheal scar contracture was observed in No.6 rabbit at 4 weeks after operation). Fourteen rabbits in group C and group D had tracheal stenosis caused by granulation tissue proliferation at 1, 2 and 3 weeks after operation. At the fourth week after operation, 71.43% of experimental rabbits had tracheal stenosis due to granulation tissue hyperplasia, 7.14% of experimental rabbits had tracheal stenosis due to scar contracture and granulation hyperplasia, and 21.43% of experimental rabbits had tracheal stenosis due to scar contracture. EB-OCT scan showed that the cartilage layer with low signal reflection band was discontinuous. The injury of cartilage is the key factor of benign airway stenosis. Acute injury of airway mucosa alone is unlikely to cause airway stenosis, but combined with cartilage injury may aggravate airway stenosis. EB-OCT can clearly identify the airway layers of rabbits, which is helpful to evaluate the damage of tracheal cartilage and mucosa. The diagnostic potential of this technique makes EB-OCT a promising approach for the study and monitoring of airway diseases. [ABSTRACT FROM AUTHOR]

For unipolar hydrodynamic model of semiconductor device represented by Euler-Poisson equations, when the doping profile is supersonic, and the boundary data are in subsonic region and supersonic region separately, the system possesses the shock transonic steady-states and the smooth transonic steady-states. In this paper we study the nonlinear structural stability and the linear dynamic instability of these steady transonic solutions. For any relaxation time: 0 < τ ≤ + ∞ , by means of elaborate singularity analysis, we first investigate the structural stability of the C 1 -smooth transonic steady-states, once the perturbations of the initial data and the doping profiles are small enough. We note that, when the C 1 -smooth transonic steady-states pass through the sonic line, they produce singularities for the system, and cause some essential difficulty in the proof of structural stability. Moreover, when the relaxation time is large enough τ ≫ 1 , under the condition that the electric field is positive at the shock location, we prove that the transonic shock steady-states are structurally stable with respect to small perturbations of the supersonic doping profile. Furthermore, we show the linearly dynamic instability for these transonic shock steady-states provided that the electric field is suitable negative. The proofs for the structural stability results are based on singularity analysis, a monotonicity argument on the shock position and the downstream density, and the stability analysis of supersonic and subsonic solutions. The linear dynamic instability of the steady transonic shock for Euler-Poisson equations can be transformed to the ill-posedness of a free boundary problem for the Klein-Gordon equation. By using a nontrivial transformation and the shooting method, we prove that the linearized problem has a transonic shock solution with exponential growths. These results enrich and develop the existing studies. [ABSTRACT FROM AUTHOR]

This paper describes and illustrates a new species of Primulaceae, Primula wolongensis sp. nov. from Wolong National Nature Reserve in Sichuan Province, China. It is very rare and currently only known from its type locality. The new species belongs to subsection Chartacea of the section Petiolares on account of lacking bud scales at flowering, being efarinose and having distinct petiolate leaves with more or less rounded lamina. The new species can be differentiated from other members of the subsection by leaf blade margin dentate, and leaf veins which are not raised, scape shorter than or equal to pedicels, yellow flowers and location of stamens of the corolla tube at thrum flower. Molecular phylogenetic analysis based on nuclear ribosome internal transcribed spacer (nrITS) demonstrated that P. wolongensis was sister to subgen. Auriculastrum. Primula wolongensis is currently known from a single location in Wolong Town, and its conservation status is assessed as Data Deficient (DD). [ABSTRACT FROM AUTHOR]

Background: Rosmarinic acid (RA) has biological and pharmaceutical properties and shows hepatoprotective potential. However, the hepatoprotective mechanism of RA needs to be further elucidated in vivo and in vitro. Objective: This study was aimed to evaluate the protective effect of RA on carbon tetrachloride (CCl4)-induced liver injury and elucidate the hepatoprotective mechanism of RA in vivo and in vitro. Design: In vivo, the mice were orally administrated with RA (10, 20, and 40 mg/kg bw) daily for 28 consecutive days, and 1% CCl4 (5 mL/kg bw, dissolved in peanut oil) was used to induce liver injury. In vitro, the big rat liver (BRL) hepatocytes were pretreated with RA (0.2, 0.4, and 0.8 mg/mL) for 3 h, and then the hepatocytes were treated with CC14 (final concentration, 14 mM) for 3 h to induce cell injury. The related indexes, including hepatic function, oxidative stress, protein expression of nuclear-factor erythroid 2-related factor 2 (Nrf2) pathway, inflammation, histopathological change, hepatocyte apoptosis, and mitochondrial membrane potential, were evaluated. Results: Oral administration of RA to mice considerably decreased the CCl4-induced elevation of serum alanine aminotransferase (ALT), alkaline phosphatase (ALP), triacylglycerols (TG), total cholesterol (TC), total bilirubin (TBIL), hepatic reactive oxygen species (ROS), malondialdehyde (MDA), nitric oxide (NO), 8-hydroxydeoxyguanosine (8-OHdG), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-8 (IL-8). RA also increased the levels of hepatic glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) and the protein expressions of Nrf2, quinine oxidoreductase (NQO1), and heme oxygenease-1 (HO-1). Histopathological examinations indicated that RA (20 and 40 mg/kg bw) alleviated the liver tissue injury induced by CCl4. Moreover, RA inhibited the hepatocyte apoptosis caused by CCl4 based on TUNEL assay. In vitro, RA pretreatment remarkably recovered the cell viability and reduced the CCl4-induced elevation of AST, ALT, lactate dehydrogenase (LDH), ROS, and 8-OHdG. Immunohistochemistry staining demonstrated that pretreatment with RA markedly inhibited the expression of IL-6, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and Caspase-3 in CCl4-treated hepatocytes. Additionally, RA pretreatment significantly decreased the elevation of mitochondrial membrane potential in CCl4-treated hepatocytes. Conclusions: RA exerted a protective effect against CCl4-induced liver injury in mice through activating Nrf2 signaling pathway, reducing antioxidant damage, suppressing inflammatory response, and inhibiting hepatocyte apoptosis. RA could attenuate BRL hepatocyte ROS production, DNA oxidative damage, inflammatory response, and apoptosis induced by CCl4 exposure. [ABSTRACT FROM AUTHOR]

Gastrochilus heminii (Orchidaceae), a new orchid species from Sichuan Province, Southwest China, is described and illustrated. It morphologically resembles G. affinis and G. yei, but differs markedly from the former in having a thinner and slightly rolled downwards reniform epichile and the central thickened purple-red mat with irregular folds (vs. subtriangular epichile curves upwards, with 2 thick, brown to purplish- brown median ridges from base to apex), and can be clearly distinguished from the latter by having reniform epichile with lobed apex and subconical hypochile with bilobed apex that splits into two conical protrusions (vs. semi-rounded epichile not lobed and subconical hypochile not bilobed). The results of molecular phylogenetic analysis based on nuclear ribosome internal transcribed spacer (nrITS) and four chloroplast DNA fragments (matK, psbA-trnH, psbM-trnD, and trnL-F) of 36 Gastrochilus species showed that G. heminii was closely related to G. affinis and G. distichus. [ABSTRACT FROM AUTHOR]

The stable isomers of (LiF)n (n = 2∼18) are obtained by using genetic algorithm combined with DFT calculations. Both the (LiF)2 and (LiF)3 are planar structures, and from n = 4, the three-dimensional structures become more energy favored. The cage-like isomers are dominated for n = 4∼12. However, (LiF)9 and (LiF)15 adopt tubular configurations, while (LiF)16 and (LiF)18 form rock-salt structures. (LiF)n (n = 2, 4, 6, 9, 12 and 15) can be considered as magic number clusters and particularly stable. There is small vertical electron affinity but large vertical ionization potential for (LiF)n. The electronic structure analysis indicates that Li atoms transferred their 2 s electrons to the 2p orbitals of F atoms, and thus form strong Li-F ionic bonds. The IR, Raman and UV–Vis spectra are also acquired. Both the electrostatic potential and the dual descriptor suggest that the locations of Li and F atoms are the optimal reaction sites. [ABSTRACT FROM AUTHOR]

• Head lice are often invisible because of their rapid movement and photophobism. • Dermoscopy visualized the adult lice, nymphs, and nits on the scalp hair. • Dermoscopic video captured two mating lice harassed by a male louse and a nymph. [ABSTRACT FROM AUTHOR]

Ga 12 N 12 is a fullerene cage and particularly stable. The surface adsorption and encapsulated storage of H 2 on the Ga 12 N 12 are thoroughly explored by applying a genetic algorithm combined with DFT calculations. The results reveal that one H 2 can form physical adsorption on the surface sites of Ga 12 N 12 with ideal adsorption intensities (−0.227∼-0.303 eV) and the mode of H 2 adsorption on a Ga atom is the most energy favored. Interestingly, the Ga 12 N 12 can adsorb a maximum of 38H 2 molecules with mass density of 7.01 wt%. The electronic structure analysis indicates that the charge transferring between H 2 and Ga 12 N 12 is observed. Meanwhile, H 2 is also effectively polarized, and thus the electrostatic interaction is improved. When H 2 is adsorbed on the Ga atom, weak covalent interactions are also induced. The encapsulation of H 2 in the Ga 12 N 12 is an endothermic process and six H 2 molecules can be encapsulated in the Ga 12 N 12 with the moderate encapsulation and releasing energy barrier of 3.286∼4.508 eV and 0.390∼3.008 eV, respectively. Our results suggest that Ga 12 N 12 is regarded as a potential hydrogen storage material. [Display omitted] • The stable isomers of Ga 12 N 12 and H 2 adsorption structures were obtained by our genetic algorithm program. • H 2 can form surface adsorption on Ga 12 N 12 with mass density of 7.01 wt%. • The hydrogen storage mechanism was discussed. • The encapsulation of H 2 in Ga 12 N 12 was also explored. [ABSTRACT FROM AUTHOR]

The development of the Light Detection and Ranging (LIDAR) technology has enabled wider options for wind turbine control, in particular regarding disturbance rejection. The LIDAR measurements provide a spatial, preview wind information, based on which the controller has a better chance to cope with the wind disturbance before it affects the turbine operation. In this paper, a model predictive controller for above-rated wind turbine control was developed with the use of pseudo-LIDAR wind measurements data. A predictive control algorithm was developed based on a linearised wind turbine model, in which the disturbance from the incoming wind was computed by the LIDAR simulator. The optimal control action was applied to the nonlinear turbine model. The developed controller was compared with the baseline control and a previously developed LIDAR-assisted control combining a feedback-and-feedforward design. Our simulation studies on a 5 MW nonlinear wind turbine model, under different wind conditions, demonstrated that the developed LIDAR-based predictive control achieved improved performance in the presence of small variations in the out-of-plane rotor torque and fore-aft tower acceleration, as well as a smoother generator speed regulation and satisfied pitch activity control constraints. [ABSTRACT FROM AUTHOR]

Directional rotary steerable is one of the key components of modern intelligent drilling, and the analysis of force and deformation in bottom hole assembly is the key to control a well trajectory. Although the introduction of edge calculation will significantly improve the case requirements in engineering application, due to the complexity of directional rotary steerable BHA, such as variable stiffness and discontinuity, few theoretical mechanical models can simultaneously solve the above problems and obtain accurate solutions. In this paper, the inclination angle and diameter of borehole are considered comprehensively. From weight on bit in drilling parameters, assembly structure parameters of multiple variable cross section, discontinuity, stabilizer diameter and position of all sorts of influencing factors, such as the vertical and horizontal bending method combined with the finite element method, a point-type rotary steering BHA is established as a new type of mechanical model, with actual project as an example, through iteration, and the calculated results with the software of numerical verify the correctness of the model. Finally, the model is used to study the bit side force of discontinuous directional rotatory stepping-type BHA, and the effects of offset, weight on bit, and distance between two stabilizers on bit side force are analyzed. The research results provide support for structure optimization and BHA parameter evaluation of directional rotary steerable tools. [ABSTRACT FROM AUTHOR]

The diruthenium-based linear mixed valence complex trans-[Ru2(ap)4-NC-Ru(DMAP)4-CN-Ru2(ap)4][PF6]2 (12+[PF6]2) (ap = 2-anilinopyridinate, DMAP = 4-dimethylaminopyridine) and its two-electron oxidation product 14+[PF6]4 have been synthesized and fully characterized. The investigation reveals that complex 12+ displays a single MMCT transition, whereas complex 14+ has three identified MMCT transitions (MMCT-1, MMCT-2 and MMCT-3) upon oxidation. Interestingly, MMCT-2 in complex 14+ might result from the transition from the RuIII-NC-RuII-CN-RuIII component, which is composed of the central RuII and its two neighboring RuIII atoms from the cluster Ru VI2 units, to both the terminal RuIII atoms of the same cluster Ru VI2 units, which is supported by the TDDFT calculations. [ABSTRACT FROM AUTHOR]

Three new mexicanolide limonoids were obtained from the 90% ethanol extract of the seeds of Khaya senegalensis. Their structures were elucidated as senegalenines A–C (1–3) by analysing their 1D/2D NMR and MS spectroscopic analysis. In addition, the isolated limonoids were tested in vitro for antimicrobial potentials against 5 pathogenic microorganisms. Consequently, compounds 1–3 exhibited antimicrobial activity against the tested Gram negative bacteria at the minimum inhibitory concentration values less than 40 μg/ml. [ABSTRACT FROM AUTHOR]

This paper evaluates how operation and maintenance (O&M) factors affect energy production and optimal deployment sites for floating offshore wind farms (FOWs) in the North Sea and the Iberian Peninsula. The geospatial analysis incorporates reliability, maintainability, accessibility, and availability aspects, and evaluates their impact on energy production. The results demonstrate that O&M factors have a significant impact on the final energy production and therefore on the identification of optimal deployment sites, both quantitatively and qualitatively. In the North Sea, promising deployment sites are identified in regions with lower wind resources but shorter turbine downtime, such as Denmark, Germany and southern Scotland. In the Iberian Peninsula, areas with high resource potential, such as the northwest Spanish and Portuguese coasts, may be less appealing than the less powerful Mediterranean regions due to lower maintainability. In particular, the efficiency of future FOW farms in the North Sea and Atlantic Ocean regions of the Iberian Peninsula heavily relies on vessel operational limits for major repairs. Increasing the significant wave height limit for major repairs from 1.5 m to 2 m results in an average capacity factor increment of 2.54% across ScotWind farms and over 6% along the northwest coast of the Iberian Peninsula. [ABSTRACT FROM AUTHOR]

It is widely known that mold is one of important indices in assessing the quality of stored wheat. First, mold will decrease the quality of wheat kernels; the wheat kernels infected by mold can produce secondary metabolites, such as aflatoxins, ochratoxin A, zearalenone, fumonisins and so on. Second, the mycotoxins metabolized by mycetes are extremely harmful to humans; once the food or feed is made of by those wheat kernels infected by mold, it will cause serious health problems on human beings as well as animals. Therefore, the effective and accurate detection of wheat mold is vitally important to evaluate the storage and subsequent processing quality of wheat kernels. However, traditional methods for detecting wheat mold mainly rely on biochemical methods, which always involve complex and long pretreatment processes, and waste part of wheat samples for each detection. In view of this, this paper proposes a type of eco-friendly and nondestructive wheat mold detection method based on ultra weak luminescence. The specific implementation process is as follows: firstly, ultra weak luminescence signals of the healthy and the moldy wheat subsamples are measured by a photon analyzer; secondly, the approximate entropy and multiscale approximate entropy are introduced as the main classification features separately; finally, the detection model has been established based on the support vector machine in order to classify two types of wheat subsamples. The receiver operating characteristic curve of the newly established detection model shows that the highest classification accuracy rate can reach 93.1%, which illustrates that our proposed detection model is feasible and promising for detecting wheat mold. [ABSTRACT FROM AUTHOR]

Purpose: Probiotics, as live microorganisms that improve intestinal microbial balance, have been implicated in the modulation of neurodegenerative diseases via the microbiome–gut–brain axis by improving gut dysbiosis. This review examines the association between probiotics and neurocognitive function in age-related dementia. Methods: We searched MEDLINE, Embase, Scopus, Web of Science and Cochrane library for in vivo studies using equivalent combinations of "probiotics" and "dementia" as per PRISMA. From the 52 in vivo studies identified, 5 human and 22 animal studies with comparable quantitative outcomes on neurocognitive/behavioural function were meta-analysed by forest plots, subgroup analysis and meta-regression. The analysis of biomarkers, risk of bias and publication bias were also performed. Results: In elderly humans, probiotics correlates with a non-significant difference of neurocognitive function in Mini-Mental State Examination, but with significant improvement only in those diagnosed with Alzheimer's disease. In animals, probiotics significantly improved neurocognitive function as measured by Morris Water Maze, Y-Maze, and Passive Avoidance. Further analysis by subgrouping and meta-regression found that the probiotics-neurodegeneration association is age dependent in humans but is neither dose dependent nor duration dependent in animals or humans. Analysis of biomarkers suggested that the neurocognitive effect of probiotics is associated with an altered gut microbiome profile, downregulated proteinopathic, inflammatory and autophagic pathways, and upregulated anti-oxidative, neurotrophic, and cholinergic pathways. Conclusion: Overall, we report promising results in animal studies but limited evidence of probiotics leading to neurocognitive improvement in humans. More research into probiotics should be conducted, especially on live biotherapeutic products for targeted treatment of gut dysbiosis and age-related dementia. [ABSTRACT FROM AUTHOR]

Drought has gradually become one of the most severe abiotic stresses on plants. Plants that experience stress training can exhibit enhanced stress tolerance. According to MicroRNA (miRNA) sequencing data, this study identified 195 candidate drought memory-related miRNAs in wheat, and targets of 64 (32.8%) candidate miRNAs were validated by degradome sequencing. Several drought memory-related miRNAs such as tae-miR9676-5p, tae-MIR9676-p3_1ss21GA, tae-miR171a, tae-miR531_L-2, tae-miR408_L-1, PC-3p-5049_3565, tae-miR396c-5p, tae-miR9778, tae-miR164a-5p, and tae-miR9662a-3p were validated as having a strong response to drought memory by regulating the expression of their target genes. In addition, overexpression of drought memory-related miRNA, tae-miR531_L-2, can remarkably improve the drought tolerance of transgenic Arabidopsisthaliana. Drought memory can regulate plant cellular signal transduction, plant biosynthetic processes, and other biological processes to cope with drought via transcriptional memory. In addition, drought memory-related miRNAs can promote starch and sucrose catabolism and soluble sugar accumulation and regulate proline homeostasis to improve plant drought resistance. Our results could contribute to an understanding of drought memory in wheat seedlings and may provide a new strategy for drought-resistant breeding. [ABSTRACT FROM AUTHOR]

A novel ratiometric electrochemical sensor was developed based on a carbon cloth electrodeposited with silver nanoparticles and drop-coated by covalent organic framework (COF-LZU1) for simultaneous determination of bisphenol A (BPA) and bisphenol S (BPS). Carbon cloth exhibited a significantly larger electrochemical active area than common glassy carbon electrodes (27.5 times). Silver nanoparticles not only provided a stable reference signal but also enhanced electroactivity for the oxidation of BPA and BPS. COF-LZU1 with good adsorption performance and large periodic π-arrays promoted the enrichment of BPA and BPS to further increase the current response. Compared with the traditional single-signal electrochemical sensor, the developed ratiometric sensor exhibited better reproducibility and a wider linear range for BPA and BPS from 0.5 to 100 μM with a limit of detection of 0.15 μM. Furthermore, the developed sensor showed excellent stability and superior anti-interference ability. The real sample analysis for BPA and BPS has been successfully carried out in mineral water, electrolyte drink, tea, juice, and beer with recoveries of 88.3–111.7%. The developed ratiometric sensor is expected to be a candidate for the preparation of other electrochemical sensors and the analysis of additional practical samples. [ABSTRACT FROM AUTHOR]

Background: Scrub typhus (ST) is a life-threatening infectious disease if appropriate treatment is unavailable. Large discrepancy of clinical severity of ST patients was reported among age groups, and the underlying risk factors for severe disease are unclear. Methods: Clinical and epidemiological data of ST patients were collected in 55 surveillance hospitals located in Guangzhou City, China, from 2012 to 2018. Severe prognosis and related factors were determined and compared between pediatric and elderly patients. Results: A total of 2,074 ST patients including 209 pediatric patients and 1,865 elderly patients were included, with a comparable disease severity rate of 11.0% (95% CI 7.1%–16.1%) and 10.3% (95% CI 9.0%–11.8%). Different frequencies of clinical characteristics including lymphadenopathy, skin rash, enlarged tonsils, etc. were observed between pediatric and elderly patients. Presence of peripheral edema and decreased hemoglobin were the most important predictors of severe illness in pediatric patients with adjusted ORs by 38.99 (9.96–152.67, p<0.001) and 13.22 (1.54–113.50, p = 0.019), respectively, while presence of dyspnea and increased total bilirubin were the potential determinants of severe disease in elderly patients with adjusted ORs by 11.69 (7.33–18.64, p<0.001) and 3.17 (1.97–5.11, p<0.001), respectively. Compared with pediatric patients, elderly patients were more likely to receive doxycycline (64.8% v.s 9.9%, p<0.001), while less likely to receive azithromycin therapy (5.0% v.s 41.1%, p<0.001). Conclusion: The disease severity rate is comparable between pediatric and elderly ST patients, while different clinical features and laboratory indicators were associated with development of severe complications for pediatric and elderly patients, which is helpful for diagnosis and progress assessment of disease for ST patients. Author summary: The study investigated different clinical features and risk factors for severe disease between pediatric and elderly patients with scrub typhus. We found that significantly higher frequencies of lymphadenopathy, skin rash, enlarged tonsils, etc. were observed in pediatric patients than elderly patients. Other non-specific signs, subjective complaints, and chest radiographic abnormality were overpresented in elderly patients. Risk factors for severe disease between pediatric and elderly patients with scrub typhus were different. Presence of peripheral edema and decreased hemoglobin were the most important factors for pediatric patients, while presence of dyspnea and increased total bilirubin for elderly patients. These findings reminded medical workers to acknowledge this important difference and to adopt an age specific method in the differential diagnosis and risk assessment for scrub typhus. [ABSTRACT FROM AUTHOR]

Variable curvature friction pendulum bearings (VCFPB) effectively reduce the dynamic response of storage tanks induced by earthquakes. Shaking table testing is used to assess the seismic performance of VCFPB isolated storage tanks. However, the vertical pressure and friction coefficient of the scaled VCFPB in the shaking table tests cannot match the equivalent values of these parameters in the prototype. To avoid this drawback, a real-time hybrid simulation (RTHS) test was developed. Using RTHS testing, a 1/8 scaled tank isolated by VCFPB was tested. The experimental results showed that the displacement dynamic magnification factor of VCFPB, peak reduction factors of the acceleration, shear force, and overturning moment at bottom of the tank, were negative exponential functions of the ratio of peak ground acceleration (PGA) and friction coefficient. The peak reduction factors of displacement, acceleration, force and overturning moment, which were obtained from the experimental results, are compared with those calculated by the Housner model. It can be concluded that the Housner model is applicable in estimation of the acceleration, shear force, and overturning moment of liquid storage tank, but not for the sliding displacement of VCFPBs. [ABSTRACT FROM AUTHOR]

In this paper, we consider the compressible Navier–Stokes–Maxwell equations with a non-constant background density in R 3 . We first show the existence and uniqueness of the non-trivial equilibrium (steady-state) of the system when the background density is a small variation of certain constant state, then we prove the asymptotic stability of the steady-state once the initial perturbation around the steady-state is small. Furthermore, by establishing the time-decay estimates for the corresponding linearized homogeneous equations, we artfully derive the time-algebraic convergence rates. The proof is based on the time-weighted energy method but with some new developments on the weight settings. [ABSTRACT FROM AUTHOR]

Ponerorchis wolongensis, a new orchid species from the Hengduan Mountains, western Sichuan, China, is described and illustrated here based on morphological and phylogenetic evidence. Morphologically, the new species is similar to P. capitata, but they can easily be differentiated by the number of leaves and flowers, the shape of leaves, and the mid‐lobe of the labellum. Phylogenetically, based on seven DNA sequences, the new species is more close to P. sichuanica, but these two species are very different in both growth habit and morphological characteristics. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study on the pullout behaviour of inclined shallow plate anchors subjected to axial pull in sand. The 1g model tests were performed to examine the effects of anchor inclination and sand–anchor interface conditions on the load–displacement response and the associated failure and deformation mechanisms of plate anchors at various embedment ratios and sand densities. The anchor pullout capacity was found to increase continuously with the load inclination angle to the vertical (α), and the increase was more significant for α from 45° to 90°. The effect of sand–anchor interface conditions was negligible for horizontal plate anchors (α = 0°), but it became increasingly significant at larger inclination angles. The effects of these two factors both decreased with an increasing embedment ratio. Their influences on the failure and deformation mechanisms were measured and analysed using a digital image correlation (DIC) technique. Based on the test data and results available in the literature, a simple empirical method for the prediction of pullout resistance of inclined plate anchors in sand is calibrated and recommended. [ABSTRACT FROM AUTHOR]

Background: China is the country with the largest elderly population. To actively respond to this ageing population, China has proposed the Community Aged Care Service Centre (CACSC) network as the major elderly care development policy. However, many residents resisted the development of the CACSC network, which affected its smooth implementation. Based on the theory of "Not in My Backyard" (NIMBY), this paper proposes a model of the influencing factors of community residents on the opposition to the construction of CACSCs.Methods: Residents living in urban communities over the age of 20 in China are the target of this study. The questionnaires were collected in the form of electronic questionnaires created on a professional website, and hyperlinks to the questionnaires were distributed through social media. The descriptive statistical analysis, T-tests, ANOVA and structural equation modelling were performed on cross-sectional survey data from 509 questionnaires.Results: The research results show that superstition, the NIMBY attitude, and perceived risk have a significant positive impact on the opposition to the construction of CACSCs, while the negative impact of perceived benefit on the opposition intention is not significant. Moreover, perceived knowledge has a significant positive impact on perceived benefit and a significant negative impact on superstition and perceived risk.Conclusions: Strengthen policy advocacy on ageing, clarify the service content of CACSC and encourage young people to participate in public welfare activities for the elderly can reduce the opposition of community residents to the construction of a CACSC. [ABSTRACT FROM AUTHOR]

To eliminate the influence of spacesuits' joint resistant torque on the operation of astronauts, an active spacesuit scheme based on the joint-assisted exoskeleton technology is proposed. Firstly, we develop a prototype of the upper limb exoskeleton robot and theoretically analyse the prototype to match astronauts' motion behavior. Then, the Jiles-Atherton model is adopted to describe the hysteretic characteristic of joint resistant torque. Considering the parameter identification effects in the Jiles-Atherton model and the local optimum problem of the basic PSO (particle swarm optimization) algorithm, a SA- (simulated annealing-) PSO algorithm is proposed to identify the Jiles-Atherton model parameters. Compared with the modified PSO algorithm, the convergence rate of the designed SA-PSO algorithm is advanced by 6.25% and 20.29%, and the fitting accuracy is improved by 14.45% and 46.5% for upper limb joint model. Simulation results show that the identified J-A model can show good agreements with the measured experimental data and well predict the unknown joint resistance torque. [ABSTRACT FROM AUTHOR]

Ottelia acuminata (O. acuminata) is an edible and medicinal submerged plant endemic to southwestern China, yet there is little information available concerning its nutritional or bio-active composition. This study aimed to evaluate in detail the nutritional profile and phenolic composition of O. acuminata (inflorescence, peduncle, and leaf) and investigate a protective activity in phenolic extracts on DNA damage induced by •OH and ROO• radicals. O. acuminata was excellent sources of protein (17.7–24 g/100 g DW), TPC (11.43–19.00 mg GAE/g DW), ascorbic acid, and minerals (especially potassium, calcium, and iron). Interestingly, the protein contained a high amount of EAA with a ratio (EAA11/TAA) in the range of 47.79–50.93%, BCAA and MSG-like AA. The inflorescences and leaves of O. acuminata contained abundant UFA with a ratio of UFA/TFA more than 50%. Five phenolic compounds, with a predominance of luteolin, luteolin-7-O-glucoside and chlorogenic acid, were identified by HPLC. Phenolic extracts of O. acuminata displayed a significant protective effect on DNA damage, which effect was comparable to that of the positive control (trolox). It was concluded that O. acuminata is an excellent vegetable with a high nutritional value and a great potential as a natural antioxidant. [ABSTRACT FROM AUTHOR]

C19H18N4O, monoclinic, P21/c (no. 14), a = 9.7995(9) Å, b = 10.0627(10) Å, c = 32.490(3) Å, β = 96.180(2)°, V = 3185.2(5) Å3, Z = 8, Rgt(F) = 0.0502, wRref(F2) = 0.1597, T = 296 K. [ABSTRACT FROM AUTHOR]

The initial value problems of bipolar isentropic/non-isentropic compressible Navier-Stokes-Maxwell (CNS-M) systems arising from plasmas in R 3 are studied. The main difficulty of studying the bipolar isentropic/non-isentropic CNS-M systems lies in the appearance of the electromagnetic fields satisfying the hyperbolic Maxwell equations. The large time-decay rates of global smooth solutions with small amplitude in L q (R 3) for 2 ≤ q ≤ ∞ are established. For the bipolar non-isentropic CNS-M system, the difference of velocities of two charged carriers decay at the rate (1 + t) − 3 4 + 1 4 q which is faster than the rate (1 + t) − 3 4 + 1 4 q (ln ⁡ (3 + t)) 1 − 2 q of the bipolar isentropic CNS-M system, meanwhile, the magnetic field decay at the rate (1 + t) − 3 4 + 3 4 q (ln ⁡ (3 + t)) 1 − 2 q which is slower than the rate (1 + t) − 3 4 + 3 4 q for the bipolar isentropic CNS-M system. The approach adopted is the classical energy method but with some new developments, where the techniques of choosing symmetrizers and the spectrum analysis on the linearized homogeneous system play the crucial roles. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study on the uplift behaviour of both pipes and strip plate anchors buried in sand. A total of 24 plane-strain uplift tests were performed using an image-based deformation measurement technique, by which the influences of anchor/pipe embedment ratio, sand relative density and pipe roughness on the load-displacement responses and associated failure and deformation mechanisms were systematically investigated. It was observed that the overall uplift responses of pipes and strip anchors were essentially similar. The peak uplift resistance of a strip anchor tended to be greater than that of a pipe at shallow depths, but the difference reduced as the sand-pipe interface frictional strength and the embedment ratio increased. Image analysis shows that the peak resistance of a shallow strip anchor/pipe was mobilised through the formation of an inverted trapezoidal block, bounded between a pair of inclined shear zones. The inclinations of the shear zones were dependent on sand dilatancy, and its average angle to the vertical for a strip anchor is slightly larger than that for a pipe. The shear zones initiate from the edges of an anchor invariably, whereas the initiation points may lie above the pipe waist, varying with sand-pipe interface conditions. These observations were used to modify a limit equilibrium method and a cavity expansion approach for predicting the peak uplift resistance of shallow pipes in sand. The modified methods were validated using a database of 125 shallow pipe uplift tests assembled from the literature. After the modifications, a good agreement with the overall database was shown, with average errors of less than 6%. [ABSTRACT FROM AUTHOR]

The implementation of horizontal wells is a key to economic development of the deep shale gas reservoir. In order to optimize the key parameters for drilling, stimulation, and the production system, the development effect of a horizontal well in deep shale gas formations was investigated from various aspects in this study. The drilling, fracturing, and production performances of this well were analyzed combining with the geological characteristics. The main technical problems and key factors that restrict the gas well performance and estimated ultimate recovery (EUR) were clarified. Through the integrated study of geology and engineering, the optimization strategies for increasing gas production and EUR are provided. The Z2 area, where the Z2-H1 well is located, has good reservoir physical properties, which bring a high drilling efficiency. However, there are still some problems during its development, such as poor fracture extension both horizontally and vertically, limited stimulated reservoir volume (SRV), rapid production declining, large water production, and serious liquid accumulation. In this study, a comprehensive approach was proposed that can improve single-well production and EUR by optimizing the target position, horizontal section length, pathway, spacing, new drilling and fracturing technology, and production system. [ABSTRACT FROM AUTHOR]

Interleukins (ILs) are cytokines with crucial functions in innate and adaptive immunity. IL genes are only found in vertebrates, except for IL-16, which has been cloned in some arthropod species. However, the function of this gene in invertebrates is unknown. In the present study, an IL-16-like gene (EsIL-16) was identified from the Chinese mitten crab Eriocheir sinensis. EsIL-16 was predicted to encode a precursor (proEsIL-16) that shares similarities with pro-IL-16 proteins from insects and vertebrates. We show that caspase-3 processes proEsIL-16 into an approximately 144-kDa N-terminal prodomain with nuclear import activity and an approximately 34-kDa mature peptide that might be secreted into the extracellular region. EsIL-16 mRNA could be detected in all analyzed tissues and was significantly upregulated after immune challenge both in vitro and in vivo. T7 phage display library screening suggested potential binding activity between EsIL-16 and integrin, which was confirmed by coimmunoprecipitation assay. Interestingly, EsIL-16 promoted cell proliferation via integrin β1 in primary cultured crab hemocytes and Drosophila S2 cells. Furthermore, the interaction between EsIL-16 and integrin β1 was necessary to efficiently protect the host from bacterial infection. To our knowledge, this study revealed integrin β1 as a receptor for IL-16 and the function of this interaction in hemocyte proliferation in invertebrates for the first time. These results provide new insights into the regulation of innate immune responses in invertebrates and shed the light on the evolution of ILs within the animal kingdom. [ABSTRACT FROM AUTHOR]

We consider stability problems for the compressible viscous and diffusive magnetohydrodynamic (MHD) equations arising in the modeling of magnetic field confinement nuclear fusion. In the first part, we investigate the Cauchy problem to the barotropic MHD system. With the help of the techniques of anti-symmetric matrix and an induction argument on the order of the space derivatives of solutions in energy estimates, we prove that smooth solutions exist globally in time near the non-constant equilibrium solutions. We also obtain the asymptotic behavior of solutions when the time goes to infinity. The result shows that gradients of both the velocity and the magnetic field converge to the equilibrium solutions with the same norm ‖ · ‖ H s - 3 , while the density converge with stronger norm ‖ · ‖ H s - 1 . In the second part, the initial value problem to the full MHD system is studied. By means of the techniques of choosing a non-diagonal symmetrizer and elaborate energy estimates, we prove the existence and uniqueness of global solutions to the system when the initial data are close to the non-constant equilibrium states. We find that both the density and temperature converge to the equilibrium states with the same norm ‖ · ‖ H s - 1 . These phenomena on the charge transport show the essential relationship of the equations between the barotropic and the full MHD systems. [ABSTRACT FROM AUTHOR]

Boron fullerenes are one type of important hydrogen storage materials, however, their performance should be further improved. Since ions can provide stronger interactions with H 2 and thus better hydrogen storage capabilities, here, we explored the structure, stabilities and hydrogen storage properties of B 36 Li 6 2 + exohedral fullerene by DFT calculations. The results show that B 36 Li 6 2 + possesses thermodynamic, dynamic and chemical stabilities due to its high geometric symmetry and closed-shell electronic structure. Furthermore, eight H 2 can be adsorbed on a Li atom with ideal adsorption energies (−0.090 ∼ − 0.201eV) and the mass density of 17.2 wt%. The non-covalent interaction between H 2 and B 36 Li 6 2 + is characteris ed and identified as Van der Waals type. The energy decomposition further reveals that the induced and electrostatic interactions mainly contribute to the adsorption energies. Our results not only deepen the understanding of non-covalent interaction in physical adsorption but also suggest that B 36 Li 6 2 + is a potential hydrogen storage material. [ABSTRACT FROM AUTHOR]

The phase transition behaviors of the shocked water are investigated by employing an optical transmittance in-situ detection system. Based on the light scattering theory and phase transformation kinetics, the phase transition mechanism of the water under multiple shocks is discussed. The experimental data indicate that the evolution of the transmittance of the shocked water can be broadly divided into three stages: relaxation stage, decline stage, and recovery stage. In the early stage of the phase transition, the new phase particles began to form around the quartz/window interface. It should be mentioned that the water/ice phase boundary seems to move toward the liquid region in one experiment of this work. Due to the new phase core being much smaller than the wavelength of the incident light, the transmittance of the sample within the relaxation stage remains steady. The decline stage can be divided into the rapid descent stage and the slow descent stage in this work, which is considered as the different growth rates of the new phase particle under different shock loadings. The recovery stage is attributed to the emergence of the new phase particles which are bigger than the critical value. However, the influence of the size growth and the population growth of the new phase particles on the transmittance restrict each other, which may be responsible for the phenomenon that the transmittance curve does not return to the initial level. [ABSTRACT FROM AUTHOR]

Polyglutamine (polyQ) expansion of proteins can trigger protein misfolding and amyloid-like aggregation, which thus lead to severe cytotoxicities and even the respective neurodegenerative diseases. However, why polyQ aggregation is toxic to cells is not fully elucidated. Here, we took the fragments of polyQ-expanded (PQE) ataxin-7 (Atx7) and huntingtin (Htt) as models to investigate the effect of polyQ aggregates on the cellular proteostasis of endogenous ataxin-3 (Atx3), a protein that frequently appears in diverse inclusion bodies. We found that PQE Atx7 and Htt impair the cellular proteostasis of Atx3 by reducing its soluble as well as total Atx3 level but enhancing formation of the aggregates. Expression of these polyQ proteins promotes proteasomal degradation of endogenous Atx3 and accumulation of its aggregated form. Then we verified that the co-chaperone HSJ1 is an essential factor that orchestrates the balance of cellular proteostasis of Atx3; and further discovered that the polyQ proteins can sequester HSJ1 into aggregates or inclusions in a UIM domain-dependent manner. Thereby, the impairment of Atx3 proteostasis may be attributed to the sequestration and functional loss of cellular HSJ1. This study deciphers a potential mechanism underlying how PQE protein triggers proteinopathies, and also provides additional evidence in supporting the hijacking hypothesis that sequestration of cellular interacting partners by protein aggregates leads to cytotoxicity or neurodegeneration. [ABSTRACT FROM AUTHOR]

In order to study the law of spontaneous combustion in goaf under the condition of gas extraction, the method of beam tube monitoring and numerical analysis is adopted to obtain three dimensional distribution of oxygen concentration and contour map under the condition of different negative pressure. Based on the way of regression analysis, reasonable negative pressure are determined. The results show that with the increase of negative pressure, the spontaneous combustion "three-zone" in goaf: the heat dissipation zone and the spontaneous combustion zone become wider and the suffocation zone narrows. At the same time, the trend of spontaneous combustion zone presents to the deep part of the goaf; the amount of gas extraction increases first and then decreases with the increase of negative pressure. Combined with the trend of spontaneous combustion zone and the amount of gas extraction in goaf, and the reasonable negative pressure value is 32kpa and verified. [ABSTRACT FROM AUTHOR]

This paper is concerned with the periodic problem to the two-fluid non-isentropic Euler–Maxwell (N-E-M) equations. The equations arises in the modeling of magnetic plasma, in which appear two physical parameters, the mass of an electron m e and the mass of an ion m i . With the help of methods of asymptotic expansions, we prove the local-in-time convergence of smooth solutions to this problem by setting m e = 1 and letting m i → + ∞ . Moreover, when the initial data are near constant equilibrium states, by means of uniform energy estimates and compactness arguments, we rigorously prove the infinity-ion-mass convergence of the system for all time. The limit system is the one-fluid N-E-M system. [ABSTRACT FROM AUTHOR]

In this work, electro-enhanced solid-phase microextraction (EE-SPME) and covalent organic framework (COF) were adopted to improve the extraction efficiency. A conductive COF synthesized of 2,6-diaminoanthraquinone (DQ) and 1,3,5-triformylphloroglucinol (TP) was in situ bonded to the stainless steel wire via facile solution-phase approach and used as the EE-SPME fiber coating to preconcentrate a typical endocrine disruptor bisphenol A (BPA). Compared with conventional SPME, the DQTP bonded fiber coupled with EE-SPME device exhibited higher extraction efficiency and achieved extraction equilibrium within 10 min. The proposed approach based on EE-SPME and gas chromatography coupled with flame ionization detector gave a linear range of 0.05–10 μ g mL−1 and detection limit of 3 μ g L−1 (S/N = 3) with good precision (<6.7%) and reproducibility (<7.1%) spiked with 0.1, 0.5, 1.0 μ g mL−1 BPA. Quantitative determination of BPA in extracts of food packagings (mineral water bottles, milk boxes and milk tea cups) was achieved with recoveries from 88.6 to 118.0%. A sampling device based on a conductive covalent organic framework (COF, DQTP) and electro-enhanced solid-phase microextraction has been constructed for rapid extraction of bisphenol A. Image 1 • Covalent organic framework DQTP was grown in situ on stainless steel wire via Schiff base reaction. • Extraction efficiency of SPME was enhanced by the external electrical field with shorter extraction time. • The developed EE-SPME coupled with GC-FID method was applied to determine bisphenol A in extracts of food packagings. [ABSTRACT FROM AUTHOR]

A soft-bound interval control problem is proposed for general non-Gaussian systems with the aim to control the output variable within a bounded region at a specified probability level. To find a feasible solution to this challenging task, the initial soft-bound interval control problem has been transformed into an output probability density function (PDF) tracking control problem with constrained tracking errors, thereby the controller can be designed under the established framework of stochastic distribution control. Fault tolerant control (FTC) is investigated for soft-bound interval control systems in presence of faults. Three fault detection methods are proposed based on criteria extracted from the initial soft-bound control problem and the recast PDF tracking problem. An integrated design for fault estimation and FTC is proposed based on a double proportional integral structure. This integrated FTC design is developed through linear matrix inequality. Extensive simulation studies have been conducted to examine the key design factors, the implementation issues and the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]