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This study reports a syringe injection pump for sample introduction for solution cathode glow discharge (SCGD) atomic emission spectroscopy (AES). The experimental conditions are optimized at 60 mA discharge current, 2.5 mm gap spacing, 2.0 mm distance from the glass capillary to cathode, 1.60 mL/min flow rate, and pH 1.0 based on the detection limits (DLs) obtained for Li, Cd, Cu, Ag, Mn, Pb, Cr, and Zn. The detection limits for Li, Cd, Cu, Ag, Mn, Pb, Cr, and Zn were 0.24, 12.26, 12.08, 1.09, 46.42, 25.81, 183.05, and 29.01 µg/L, respectively, significantly lower than using the traditional peristaltic pump. The detection limits decreased by 1.4, 1.8, 2.2, 5.0, 1.4, 1.4, 1.4, 1.6, and 2.2-fold for these elements. The flow rate and the solution consumed per unit time were significantly reduced using this design. The spectral detection revealed stable and practical operation of the system with relative standard deviations <0.85%. Water samples from Yangtze River, Baixi River, and Baiyun Reservoir are analyzed using the modified SCGD system and its evaluation is based upon comparison to inductively coupled plasma—optical emission spectroscopy (ICP-OES). The modified device operates at atmospheric pressure without inert gas and integrates a syringe injection pump and a compact spectrometer to optimize solution utility, analytical performance, and operation size for industrial and environmental monitoring applications. [ABSTRACT FROM AUTHOR]

Purified SpyCatcher-ATA117 (5 µM) and SpyTag-ADH (5 µM) were covalently combined to form self-assembled dual-enzyme clusters (DENCs) at 4 °C for 3 h. The successful assembly of DENCs was verified using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and dynamic light scattering (DLS). DENCs improved the storage stability by 36.2% and pH stability by 11.2% compared with those of free double enzymes. 56.89 g/L (R)− 1-[3,5-bis(trifluoromethyl)phenyl]ethanamine (R -BPA) was synthesized using DENCs with high yield (99.9%) and high enantiomeric excess (99.9%) at 45 °C and pH 9 for 24 h. Moreover, DENCs retained more than 78% of the initial activity after being reused in the preparation of R -BPA for five cycles. Thus, DENCs were successfully formed, and efficient amination was achieved, providing a new biocatalyst for efficient biosynthesis of chiral amines via asymmetric transamination cascade reaction. [Display omitted] • Self-assembled dual-enzyme clusters (DENCs) were effectively prepared. • DENCs were prepared by the SpyTag/SpyCatcher conjugation strategy. • Evaluated the effects of self-assembly conditions on relative enzyme activity of DENCs. • DENCs improved storage stability and pH stability than free double enzymes. • DENCs exhibited high reusability after five cycles. [ABSTRACT FROM AUTHOR]

Earthquake-induced landslides are complex dynamic processes, a better understanding of which can be achieved by studying the entire dynamic process, including the propagation of seismic waves, cracking, instability, movement, and deposition. This paper explores the entire dynamic process in combination with the propagation of seismic waves and crack developing process of the slope under earthquake actions, while taking into account the strength attenuation, the major factor that causes the high-speed and long-runout movement. In this study, a simulation analysis tool called discontinuous deformation analysis (DDA) was used and improved by incorporating a seismic input method based on a viscous boundary and the free-field theory, virtual and real joints, and a shear strength attenuation criterion, to conduct a unified simulation analysis of the whole dynamic process of earthquake-induced landslide, and to analyze the influence of the dynamic response law on the instability and motion of landslide. Based on these improvements, the Donghekou landslide caused by the Wenchuan earthquake in 2008 was simulated. The dynamic characteristics of the slope showed an obvious amplification effect. At places with strong dynamic responses, cracks initiated rapidly. The progressive crack developing process of the landslide was represented. Owing to the low-friction effect, the speed increased sharply after the landslide began, promoting its high speed and long runout. From the crack propagation in the slope and the formation process of the sliding surface, it is evident that the Donghekou landslide was a typical tension-cracking and shearing sliding landslide. Highlights: The entire dynamic process analysis landslide method, from continuous to discontinuous, was established. The influence of the site dynamic response to the formation of a landslide was considered. The instability mechanism of a landslide was analyzed based on the fragmentation process. [ABSTRACT FROM AUTHOR]

It has been shown that there exist unextendible product bases (UPBs) with sizes of 6, 8, 9, and 10 in the 5-qubit system. These product vectors are not UPB any more when they are regarded as product vectors in the coarsened systems (i.e., some subsystems are merged, e.g., if two subsystems are merged, the system becomes 2 ⊗ 2 ⊗ 2 ⊗ 4 ). In this paper, we show that these product states can be expanded to UPBs in the coarsened system by adding some product vectors. Comparing with the existing UPBs, we get a series of novel UPBs which have different sizes or have the same size as that of the existing ones but are not equivalent to them. [ABSTRACT FROM AUTHOR]

Cascade reactions catalyzed by multi-enzyme systems are important in science and industry and can be used to synthesize drugs and nutrients. In this study, two types of macromolecules of bi-enzyme self-assembly clusters (BESCs) consisting of carbonyl reductase (CpCR) and glucose dehydrogenase (GDH) were examined. Stereoselective CpCR and GDH were successfully fused with SpyCatcher and SpyTag, respectively, to obtain four enzyme modules, namely: SpyCatcher-CpCR, SpyCatcher-GDH, SpyTag-CpCR, and SpyTag-GDH, which were covalently coupled in vitro to form two types of hydrogel-like BESCs: CpCR-SpyCatcher-SpyTag-GDH and GDH-SpyCatcher-SpyTag-CpCR. CpCR-SpyCatcher-SpyTag-GDH showed a better activity and efficiently converted ethyl 2-oxo-4-phenylbutyrate (OPBE) to ethyl(R)2-hydroxy-4-phenylbutanoate ((R)-HPBE), while regenerating NADPH. At 30 °C and pH 7, the conversion rate of OPBE with CpCR-SpyCatcher-SpyTag-GDH as a catalyst reached 99.9%, with the ee% of (R)-HPBE reaching above 99.9%. This conversion rate was 2.4 times higher than that obtained with the free bi-enzyme. The pH tolerance and temperature stability of the BESCs were also improved compared with those of the free enzymes. In conclusion, bi-enzyme assemblies were docked using SpyCatcher/SpyTag to produce BESCs with a special structure and excellent catalytic activity, improving the catalytic efficiency of the enzyme. [ABSTRACT FROM AUTHOR]

(R)-1-[3,5-bis(trifluoromethyl)phenyl]ethanamine, a key chiral intermediate of selective tetrodotoxin-sensitive blockers, was efficiently synthesized by a bienzyme cascade system formed by with R-ω-transaminase (ATA117) and an alcohol dehydrogenase (ADH) co-expression system. Herein, we report that the use of ATA117 as the biocatalyst for the amination of 3,5-bistrifluoromethylacetophenone led to the highest efficiency in product performance (enantiomeric excess > 99.9%). Moreover, to further improve the product yield, ADH was introduced into the reaction system to promote an equilibrium shift. Additionally, bienzyme cascade system was constructed by five different expression systems, including two tandem expression recombinant plasmids (pETDuet-ATA117-ADH and pACYCDuet-ATA117-ADH) and three co-expressed dual-plasmids (pETDuet-ATA117/pET28a-ADH, pACYCDuet-ATA117/pET28a-ADH, and pACYCDuet-ATA117/pETDuet-ADH), utilizing recombinant engineered bacteria. Subsequent studies revealed that as compared with ATA117 single enzyme, the substrate handling capacity of BL21(DE3)/pETDuet-ATA117-ADH (0.25 g wet weight) developed for bienzyme cascade system was increased by 1.50 folds under the condition of 40 °C, 180 rpm, 0.1 M pH9 Tris-HCl for 24 h. To the best of our knowledge, ours is the first report demonstrating the production of (R)-1-[3,5-bis(trifluoromethyl)phenyl]ethanamine using a bienzyme cascade system, thus providing valuable insights into the biosynthesis of chiral amines. [ABSTRACT FROM AUTHOR]

Universities are important parts of innovation ecosystems, and university technology transfer (UTT), which aims for the sustainable commercialization of sci-tech achievements, is closely related to other actors in the ecosystem. Based on the panel data of 31 provinces in mainland China, this paper empirically analyzes the spatiotemporal distribution characteristics of UTT levels from 2011 to 2019 and estimates the influencing factors using the spatial Durbin model (SDM) with an economic spatial weighting matrix from the perspective of innovation ecosystems. The results are presented as follows: (1) Although the overall level of UTT in China is low, it shows an upward trend in most provinces. In addition, the interprovincial gap is obvious, forming a ladder distribution of UTT levels increasing from west to east. (2) There is a significant spatial autocorrelation between UTT levels in the provinces. (3) Industry, economy, and informatization play significant roles in promoting UTT, while financial institutes and openness have significant inhibitory effects. The economy has a significant spatial spillover effect on UTT, while government, industry and informatization have a significant inhibitory effect on UTT in neighboring regions. (4) The direct and indirect effects of influencing factors in the Eastern Region and other regions show significant spatial heterogeneity. [ABSTRACT FROM AUTHOR]

In anurans, the complexity of courtship calls may affect female mate choice. The current study suggests that nonlinear phenomena (NLP) components can contribute to increasing complexity in courtship calls and attracting female attention. The results of a recent study showed that calls of large odorous frog (Odorrana graminea) contained NLP components. However, whether the nonlinear components of courtship calls in O. graminea improve male attractiveness remains unknown. We hypothesized that female O. graminea would prefer males producing calls with a higher proportion of NLP components (P‐NLP‐C). To test this hypothesis, we recorded the advertisement calls of 28 males and confirmed that the P‐NLP‐C was significantly positively related to body size. We also measured the body size of natural amplectant males and non‐amplectant males in the field and found that amplectant males had larger body sizes than non‐amplectant males, and the results of two‐choice amplexus experiments similarly revealed a female preference for males with larger body sizes. Additionally, phonotaxis experiments also revealed that females preferred male calls with a high P‐NLP‐C. The results suggest that a higher P‐NLP‐C in calls can enhance male attractiveness, and the P‐NLP‐C may provide key information about male body conditions for female O. graminea. Our study provides a new insight for better understanding the role of NLP in anuran mate selection. [ABSTRACT FROM AUTHOR]

• The specific recognition fluorescent sensor (NH 2 -MIL-53/MIP) was prepared. • The sensor combines the advantages of MOFs and molecularly imprinted polymers. • The developed sensor has high selectivity and fast response time to tetracycline. • The sensing mechanism is attributed to photoinduced electron transfer. • NH 2 -MIL-53/MIP can effectively determine TC in real samples. Molecularly imprinted fluorescent sensors are of interest to researchers due to their specificity, high sensitivity, and stability. In this study, the fluorescence-imprinted sensor (NH 2 -MIL-53/MIP) for the detection of tetracycline (TC) in animal-derived foods was developed based on the characteristics of luminescent metal-organic frameworks (MOFs) and molecularly imprinted polymers (MIPs). The MOFs provide fluorescence sensing signals and large specific surface areas, while the MIPs provide the specific recognition sites for TC. As a result, the sensor exhibits a wide detection range (0.05–50 μg/mL), high sensitivity (LOD of 0.006 μg/mL), fast detection speed and good selectivity. The sensing principle can be attributed to photoinduced electron transfer. Furthermore, the sensor can determine TC in milk with good recovery rates (95.05–104.71 %). This work addresses the limitation of current molecularly imprinted sensors such as slow corresponding speed and limited detection capability, providing valuable insights for target determination in complex systems. [ABSTRACT FROM AUTHOR]

Earlier spring phenological events have been widely reported in plants under global warming. Recent studies reported a slowdown in the warming‐induced advanced spring phenology in temperate regions. However, previous research mainly focused on daily mean temperature, thus neglecting the asymmetric phenological responses to daytime and nighttime temperature. Using long‐term records of leaf unfolding in eight deciduous species at 1300 sites across central Europe, we assessed and compared the effects of daytime temperature, nighttime temperature, and photoperiod on leaf unfolding during 1951–1980 and 1981–2013. Although leaf unfolding was advanced by daytime warming during 1951–2013, the advancing responses of leaf unfolding significantly decreased from 1951–1980 to 1981–2013 due to a lower accumulation of chilling units by daytime warming. Nighttime warming delayed leaf unfolding during 1951–1980 but advanced it during 1981–2013 due to a higher accumulation of chilling units by nighttime warming. In contrast, critical daylength and plasticity of leaf unfolding dates remained unchanged between 1951 and 2013. Our study provided evidence that daytime warming instead of nighttime warming accounts for the slowdown in the advancing spring phenology and implied that nighttime warming‐induced earlier spring phenology may be buffering the slowdown of the advanced spring phenology by daytime warming. The response of spring phenology to nighttime temperature may override that to daytime temperature under the actual trends in global warming. [ABSTRACT FROM AUTHOR]

Currently, the dynamic behavior of high-speed long-runout landslides triggered by earthquakes remains unclear due to the complexity of such phenomena. Degradation in the shear strength of rock masses is considered a primary factor contributing to the high velocities and long runout distances of these landslides. In this study, the strength degradation induced by changes in rock joint morphology is analyzed considering a numerical model of the Donghekou landslide, by using discontinuous deformation analysis (DDA). First, an exponential joint roughness degradation function (i.e., JRCm) that depends on displacement is incorporated with the nonlinear Barton–Bandis (B–B) shear strength criterion, and this modified B–B criterion is combined with the DDA. Moreover, a virtual joint is introduced in the DDA to model the propagation of cracks in intact rock masses, in order to simulate the dynamic phenomenon of earthquake-induced landslides. Subsequently, this improved DDA (IDDA) is validated via simulations of a shear test and a sliding block over an inclined plane. Finally, the IDDA is employed to simulate the Donghekou landslide, which was induced by the 2008 Wenchuan earthquake in China. Furthermore, the entire dynamic process of the landslide, including crack propagation, instability, initiation, and motion, is depicted. The simulated deposit patterns obtained via the IDDA are in good agreement with the results of field investigations. The simulation results also prove that the IDDA can reflect key movement behaviors of Donghekou landslide and that the degradation of rock joints significantly influences the long runout distance and high velocity of sliding mass. [ABSTRACT FROM AUTHOR]

Site period has been widely acknowledged to be a reasonable site parameter for ground-motion modeling and site effect modeling. Its value could be analytically calculated using the shear-wave velocity (V S) profile by assuming that soil layers overlie a rigid bedrock, or empirically estimated from the horizontal-to-vertical spectral ratio (HVSR). In this study, we tested the uncertainty of site period on the variability of the site period-based ground-motion prediction equations (GMPEs). The ground-motion records and site data in Japan were used. We first used different V S values as engineering bedrock to derive a set of analytical site periods, and tested the uncertainty because of the bedrock V S selection on the GMPE variability. The results show that adding information about the stiff-soil or soft-rock layer beneath the surface soft-soil layers would significantly improve site effect prediction accuracy. An engineering bedrock with V S equal to about 800 m/s is recommended. We then tested the uncertainty of site period because of the choice between the analytical one and the empirical one on the GMPE variability. The empirical site period is better than the analytical site period at spectral periods from 0.06s to 0.4s. At spectral periods longer than 0.4s, the empirical site period produces larger variability than the analytical one using V S ≥ 800 m/s bedrock and has a better performance than that using V S < 600 m/s bedrock. The larger variability is partly contributed by the uncertainty in identifying site period value from the HVSR curve. Using the site period from the first peak of the HVSR curve generally produces a smaller variability than that from the highest peak. For sites with more than one comparable peak in the HVSR curve, the site period from the first peak is recommended. For the regions out of Japan, cautions may be paid for these recommendations because of the potential region dependence of site response. • The uncertainty of site period on variabilities of ground-motion prediction equations is presented. • The modeling effects between the site period derived from V S profiles and that estimated from HVSR curves are compared. • A V S = 800 m/s bedrock is recommended in practice if a V S profile is used for site period calculation. • The site period derived from the first peak of the HVSR curve is recommended if multiple comparable peaks are identified. [ABSTRACT FROM AUTHOR]

A collinear dual-pulse laser induced breakdown spectroscopy (DP-LIBS) method was employed to analyze Chinese traditional medicine Artemisia annua. The spectral intensities and signal-to-background ratios of magnesium (II) 279.54 nm, CN 388.29 nm, calcium (II) 393.37 nm, and iron (II) 404.27 nm were used to evaluate the optical emission characteristics of A. annua induced by DP-LIBS. The temporal evolution characteristics, inter-pulse time, and laser energy values were optimized. In particular, the electron density and the temperatures of the plasma were reported as functions of the delay time. The results showed that the DP-LIBS had stronger intensity and better accuracy compared to single-pulse (SP) LIBS. The enhancement factors obtained using DP-LIBS for Mg, CN, Ca, and Fe were 7.2, 8.9, 13.8, and 3.4, respectively. This study provides important information about A. annua. [ABSTRACT FROM AUTHOR]

A long-term sustainable tungsten cathode-solution anode glow discharge (SAGD) source for atomic emission spectrometry was developed for the determination of heavy metal elements. The tungsten cathode of this source was cooled by a compact refrigeration semiconductor, which is simple in design and able to operate at atmospheric pressure for long periods. When the equipment operates at its optimal conditions (75 mA discharge current, 2.0 mm discharge gap, 3.8 mL min−1 flow rate, and solution pH value of 2.0), the detection limits of Ag (338.24 nm), Cd (228.80 nm), Hg (253.66 nm), Pb (368.28 nm), Tl (337.52 nm), and Zn (213.79 nm) were explored, and the values were 0.030, 1.7, 7.2, 17, 0.24, and 25 μg L−1, respectively. The interference of coexisting ions in water, such as K+, Ca2+, Na+, Mg2+, and Li+, on the analytical performance of the solution anode glow discharge-atomic emission spectrometry (SAGD-AES) for Cd, Hg, Pb, and Zn were investigated. The results showed that coexisting metal ions' interferences are insignificant. The SAGD-AES system was successfully applied for analyzing water samples from the Yangtze River and Baixi River, and its accuracy and practicality were verified by comparison with inductively coupled plasma-optical emission spectrometry (ICP-OES) results. [ABSTRACT FROM AUTHOR]

In order to investigate the influence of laser wavelength on the detection of the metals in Artemisia annua, pulsed lasers operating at wavelengths of 1064 nm and 532 nm for laser induced breakdown spectroscopy (LIBS) have been employed to generate the plasma. The spectral lines of Mg (II) at 279.54 nm, CN at 388.29 nm, Ca (II) at 393.37 nm and Fe (II) at 404.27 nm were used to evaluate the optical emission at various delay times for the 532 nm and the 1064 nm laser. The effects of the data acquisition delay time on the line intensity, signal-to-background ratio and the characteristic parameters of laser plasma have been investigated as well. The results show that the 1064 nm beam induced plasmas with higher signal-to-background ratios and temperatures than the 532 nm beam. However, the 532 nm laser beam produced plasma with higher electron densities than the 1064 nm laser beam. In addition, a significant influence has been found: the spectral intensities of the ions were stronger than the spectral intensities of the atoms independent of whether the laser was operated at 532 nm or 1064 nm. [ABSTRACT FROM AUTHOR]

Edge-to-edge is the most common form of contact in a two-dimensional joint block system. Discontinuous deformation analysis (DDA) is a powerful tool for handling block systems and treats an edge-to-edge contact as two vertex-to-edge contacts with a couple of normal and shear springs at the extremes of the contact segment. However, this method is unsuitable for evaluating the tensile failure of a joint under asymmetrical tension conditions, even though it can simplify the contact type and increase computational efficiency. This is mainly because the distributed forces at an edge-to-edge contact are simplified as two couples of concentrated forces. To solve this problem, this paper proposes incorporating a multi-spring edge-to-edge contact model with DDA. In the model, several contact pairs with normal and shear springs on an edge-to-edge contact are set to simulate the distributed forces. Several benchmark tests were performed to demonstrate the discrepancy between the original and improved DDAs. The results revealed that the latter more accurately models the stress distribution across the edge-to-edge contact, providing a more reasonable acceleration required to topple a series of blocks resting on an inclined stepped base. [ABSTRACT FROM AUTHOR]

Introduction: Acute respiratory distress syndrome (ARDS) is a life-threatening medical condition. It is characterized by serious lung inflammation or injury. Characterizing novel miRNAs implicated in ARDS pathogenesis may provide new therapeutic strategy for managing ARDS. Methods: We employed LPS-induced lung injury model to profile miRNAs associated with ARDS. We isolated one miRNA candidate and characterized its role in lipopolysaccharide (LPS)-induced proinflammatory cytokine production in lung macrophages. We further evaluated its functional role in ARDS model by assessing histological change, neutrophil activation, tissue permeability and tumor necrosis factor alpha (TNFα) production. We also characterized its downstream target using luciferase assay, Western blotting, enzyme-linked immunosorbent assay and cell inflammation assay. Results: Microarray profiling revealed miR-802 was significantly downregulated in ARDS mouse model. LPS-induced miR-802 downregulation was confirmed in lung macrophages. Overexpression of miR-802 significantly suppressed LPS-induced inflammatory cytokine production in vitro and alleviates LPS-induced acute lung injury in vivo. Peli2 was identified as a downstream target of miR-802 and found upregulated in ARDS model. Overexpressing Peli2 abolished the antagonizing effect of miR-802 on LPS-mediated inflammatory response. Conclusion: MiR-802 carried a protective role against LPS-induced acute lung injury by downregulating Peli2. MiR-802/Peli2 axis may act as intervening targets to manage ARDS. [ABSTRACT FROM AUTHOR]

Most mechanical oil leaks and industrial oily wastewater are in complex and harsh environments. Hence, developing a simple and efficient method to store oil or separating oil–water contaminants has become an ongoing challenge. Hierarchically porous polyetheimide (HPPEI) is a promising competitive candidate due to the combination of functional designability, featuring multilayer pores, and the excellent properties of PEI. Herein, HPPEI (micro‐ and nano‐) is developed by fused deposition modeling (FDM) printing, which enables customizable uniform pores, and green and cost‐effective supercritical CO2 foaming method. HPPEI exhibits remarkable oil content and oil adsorption rate, attributed to the nanopores functioning as "windows." Nanopores alter the adsorption mode from the "individual adsorption" of PPEI to "interconnected adsorption," accompanied by an increased storage capacity, and enhanced the overall adsorption rate due to strong capillary effect and higher adsorption rate. HPPEI modified with hydrophobic nano fumed silica (HN─SiO2), demonstrates outstanding hydrophobicity and lipophilicity features selective oil adsorption and oil–water separation, and retains excellent hydrophobic even at high temperatures and in acidic and alkaline environments. This material is expected to provide a strategy for energy conservation: selective oil adsorption from oily wastewater in harsh environments and then the oily material is utilized for lubrication areas, avoiding material waste. [ABSTRACT FROM AUTHOR]

In order to determine metal ions in aqueous solution, a millisecond pulsed solution cathode glow discharge (SCGD) source coupled with a portable spectrometer was developed for atomic emission spectrometry (AES). The millisecond pulsed SCGD source was operated with two high-voltage DC power supplies and a high-voltage pulse switch, specifically boosting the analyte excitation and sustain the glow discharge. The method to excite the plasma discharge contrasts with traditional approaches that employ a single power source. The influence of operating parameters, including pulsed voltage, pulsed frequency, duty ratio, and sample flow rate, were optimized to construct a system having good stability and improved excitation of metal ions. The optimum detection limits for Na, K, Li, Mg, Ag, Cs, Rb, and Sr were 0.17, 0.32, 0.38, 0.50, 2.65, 1.30, 0.22, and 74.02 µg·L−1, respectively. Furthermore, mountain spring, Yangtze River, and reservoir water were spiked with Ag, Rb, and Cs; the recoveries ranged from 105% to 106%, 106% to 107%, and 107% to 108% indicating that the developed system has favorable analytical performance. [ABSTRACT FROM AUTHOR]

A novel-pulsed electrolyte cathode atmospheric pressure discharge (pulsed-ECAD) plasma source driven by an alternating current (AC) power supply coupled with a high-voltage diode was generated under normal atmospheric pressure between a metal electrode and a small-sized flowing liquid cathode. The spatial distributions of the excitation, vibrational, and rotational plasma temperatures of the pulsed-ECAD were investigated. The electron excitation temperature of H Texc(H), vibrational temperature of N2 Tvib(N2), and rotational temperature of OH Trot(OH) were from 4900 ± 36 to 6800 ± 108 K, from 4600 ± 86 to 5800 ± 100 K, and from 1050 ± 20 to 1140 ± 10 K, respectively. The temperature characteristics of the dc solution cathode glow discharge (dc-SCGD) were also studied for the comparison with the pulsed-ECAD. The effects of operating parameters, including the discharge voltage and discharge frequency, on the plasma temperatures were investigated. The electron number densities determined in the discharge system and dc-SCGD were 3.8-18.9 × 1014 cm-3 and 2.6 × 1014 to 17.2 × 1014 cm-3, respectively. [ABSTRACT FROM AUTHOR]

Herein, a pulsed electrolyte cathode atmospheric pressure discharge (pulsed-ECAD) system was developed as a radiation source for the atomic emission spectroscope (AES) for metal element determination in aqueous solutions. The time-resolved emission spectra of the pulsed-ECAD were obtained at various frequencies, and their evolution behaviours during the modulation period were found to exhibit a strong dependence on the modulation frequency. The temporal behaviors of the metal element spectral intensities of K, Na, Li, Rb, Sr, and Mg as well as the atomic and molecular species emissions originating from water and air (OH, Hα, Hβ, N2, and O) were characterized from the plasma. The temporal evolutions of the pulsed-ECAD plasma parameters, including the rotational temperature, electron density, and ionization temperature, were analyzed. The results showed that the rotational temperatures varied between 950 K and 1350 K. The electron density and ionization temperature ranges of Mg were from 4.3 × 1014 to 2.2 × 1015 cm−1 and from 5200 K to 5500 K, respectively. [ABSTRACT FROM AUTHOR]

Chinese herbal medicine has attracted increasing attention because of the unique and significant efficacy in various diseases. In this paper, three types of Chinese herbal medicine, the roots of Angelica pubescens, Codonopsis pilosula, and Ligusticum wallichii with different places of origin or parts, are analyzed and identified using laser-induced breakdown spectroscopy (LIBS) combined with principal component analysis (PCA) and artificial neural network (ANN). The study of the roots of A. pubescens was performed. The score matrix is obtained by principal component analysis, and the backpropagation artificial neural network (BP-ANN) model is established to identify the origin of the medicine based on LIBS spectroscopy of the roots of A. pubescens with three places of origin. The results show that the average classification accuracy is 99.89%, which exhibits better prediction of classification than linear discriminant analysis or support vector machine learning methods. To verify the effectiveness of PCA combined with the BP-ANN model, this method is used to identify the origin of C. pilosula. Meanwhile, the root and stem of L. wallichii are analyzed by the same method to distinguish the medicinal materials accurately. The recognition rate of C. pilosula is 95.83%, and that of L. wallichii is 99.85%. The results present that LIBS combined with PCA and BP-ANN is a useful tool for identification of Chinese herbal medicine and is expected to achieve automatic real-time, fast, and powerful measurements. [ABSTRACT FROM AUTHOR]

Solution-cathode glow discharge-atomic emission spectrometry (SCGD-AES) with a portable spectrometer was used to detect metal elements in solution. A modified pulsation damper was designed and optimized to improve discharge plasma stability. The effects of pulsation damper parameters as well as the discharge current and solution flow rate were investigated. The plasma stability of Na, K and Li elements under optimized parameters with the modified pulsation damper was discussed and they showed good stability over a long time. The standard deviation (SD) of background intensity was low, and the detection limits for Zn, Mg, Ag, Pb, Sr, Na, Li, K, Rb and Cs were 72, 2.1, 1.2, 35, 86, 0.04, 0.16, 0.14, 0.38 and 1.1 μg L−1, respectively. Ag, Zn and Pb elements in a certified reference material were quantitatively analyzed, and the measurement results obtained by SCGD-AES agreed well with the reference values. Specifically, the precision (relative standard deviation of 10 measured values) of detection was lower than 1.85%. The results show that the SCGD-AES system with the modified pulsation damper can accurately and stably detect the content of metal elements in water. [ABSTRACT FROM AUTHOR]

Implementing a closed-loop supply chain in the appliance industry offers great practical significance given the characteristics of remanufacturing the decomposed parts of end-of-life electrical and electronic products. However, only few studies have analyzed the integration of a closed-loop supply chain for such products. To characterize this supply chain, find a suitable recovery mode, and determine its pricing strategy, a closed-loop supply chain with a manufacturer, retailer, third party recycling center, and consumers was designed. Afterward, a new joint recovery mode conducted by a retailer and third party recycling center was determined, and some pricing decision models under different mechanisms were built. Finally, corresponding operations management strategies were proposed by comparing pricing decision strategies under the cooperative and non-cooperative mechanisms based on game theory and optimization theory. The results demonstrate that the optimal selling price of each member enterprise under different mechanisms is the decreasing function of the sensitivity coefficient of consumers to selling price. Meanwhile, the overall profit of a closed-loop supply chain under different mechanisms gradually increases along with the proportion of remanufactured parts in end-of-life electrical and electronic products that can be directly used in remanufacturing. Moreover, Adopting different remanufacturing strategies under various operating mechanisms can differentiate the levels of profit. The proposed joint recovery mode is generally supportive of transaction cost theory, and the pricing strategy under different mechanisms is expected to have practical implications for enterprises to improve their operation benefits. [ABSTRACT FROM AUTHOR]

Laser-induced breakdown spectroscopy was used for the analysis of the Chinese traditional medicine,Ligusticum wallichii. The laser energy and delay time were optimized to obtain best spectral quality. The limits of detection for lead and copper were 15.7 and 6.3 µg g−1, respectively. Multiple linear regression models between the laser-induced breakdown spectroscopy intensity and the mass fraction of lead and copper were constructed. Good agreement was observed between the actual concentrations and predicted values obtained by the models. These results demonstrate that the laser-induced breakdown spectroscopy coupled with multiple linear regression is suitable for the determination of heavy metals in Chinese traditional medicine. [ABSTRACT FROM PUBLISHER]

Five polysaccharides, namely ADPs-1a, ADPs-1b, ADPs-2, ADPs-3a and ADPs-3b, were extracted from Angelicae dahuricae Radix, purified, and identified by high performance gel permeation chromatography (HPSEC), gas chromatography (GC), Fourier transform infrared (FT-IR) spectrometer and nuclear magnetic resonance spectra (NMR), including the determination of procoagulant activity in vitro. The average molecular weight ( Mw) of the polysaccharides was 153,800, 8312, 111,700, 3766 and 96,680 g/mol, respectively. Coagulation assays indicated that ADPs-1b, ADPs-2, ADPs-3a and ADPs-3b had procoagulant activities. ADPs-1b exerted the procoagulant activities through intrinsic pathway, extrinsic pathway and increased the content of FIB in vitro. ADPs-2 exerted the procoagulant activities through intrinsic pathway and extrinsic pathway. ADPs-3a had procoagulant activities and the activity was associated with the intrinsic pathway and increased the content of FIB. ADPs-3b exerted the activities through extrinsic pathway and increased the content of FIB. [ABSTRACT FROM AUTHOR]

Zwitterionic polymers are known to possess excellent protein resistance due to high hydration capacity of their zwitterionic moieties. In this study, polysaccharide-based zwitterionic polymers 3-dimethyl(propyl) ammonium propanesulfonate starches (Z-starches) with different degrees of substitution of the zwitterionic moieties (DSZM) were synthesized successfully. The value of DSZM can be controlled exactly in the range of 0-0.46. The cytotoxicity of Z-starches with different DSZM was evaluated by an MTT assay, and the Z-starch with DSZM of 0.26 promoted cell proliferation when the concentration of this polymer solution was 1-25 mg/mL. The protein resistance and cell adhesion of Z-starch hydrogels were evaluated, and the amount of protein adsorption or cell adhesion on Z-starch hydrogels was decreased as the DSZM increased. The preliminary protein resistance and cell adhesion tests suggest that the Z-starches have potential applications in drug delivery carriers and coatings of implanted sensors where protein resistance is needed. [ABSTRACT FROM AUTHOR]

This paper studies the run-out of earthquake-induced landslides. There are more than 20 mechanical models to explain long run-out of rapid landslides including some earthquake-induced landslides. However, notably few of them considered the effect of seismic loading on the run-out of landslides. In a previous study, we have proposed a model, which is called the multiplex acceleration model (MAM), to interpret the long run-out mechanism, and a shaking-table test has been performed to verify the MAM. Because the previous MAM is a conceptual model and only a single stone has been examined under sine waves by the shaking-table test, the MAM needs to be extended and further verified. In this paper, the MAM was extended by introducing the movement change that was induced by the so-called trampoline effect of earthquake loading, and the latest practical numerical simulation program, discontinuous deformation analysis (DDA), was used to verify the mobility of earthquake-induced landslides. After a conceptual landslide model was used to verify the effect of seismic loading on the mobility, the Donghekou landslide, which was a typical long run-out landslide that was induced by the 2008 Wenchuan earthquake, was analyzed. The results show that: the seismic loading could be one of the factors that could eventually help increase the run-out of landslides. [ABSTRACT FROM AUTHOR]

Non-fouling materials bind water molecules via either hydrogen bonding or ionic solvation to form a hydration layer which is responsible for their resistance to protein adsorption. Three ionic starch-based polymers, namely a cationic starch (C-Starch), an anionic starch (A-Starch) and a zwitterionic starch (Z-Starch), were synthesized via etherification reactions to incorporate both hydrogen bonding and ionic solvation hydration groups into one molecule. Further, C-, A- and Z-Starch hydrogels were prepared via chemical crosslinking. The non-fouling properties of these hydrogels were tested with different proteins in solutions with different ionic strengths. The C-Starch hydrogel had low protein resistance at all ionic strengths; the A-Starch hydrogel resisted protein adsorption at ionic strengths of more than 10 mM; and the Z-Starch hydrogel resisted protein adsorption at all ionic strengths. In addition, the A- and Z-Starch hydrogels both resisted cell adhesion. This work provides a new path for developing non-fouling materials using the integration of polysaccharides with anionic or zwitterionic moieties to regulate the protein resistance of materials. [ABSTRACT FROM AUTHOR]

A novelpolysaccharide-based zwitterionic copolymer, agarose-graft-poly[3-dimethyl (methacryloyloxyethyl) ammonium propanesulfonate](agarose-g-PDMAPS) with UCST, depending both on hydrogenbonding and electrostatic interaction, was synthesized by ATRP, andits aggregation behavior in aqueous media was investigated in detail.Proton nuclear magnetic resonance spectroscopy, Fourier transform-infraredspectroscopy, and gel-permeation chromatography were performed tocharacterize the copolymer. Thermosensitive behaviors of the copolymersin water, NaCl, and urea solution were tracked by ultraviolet, dynamiclight scattering, and transmission electron microscopy analysis. Itwas found that the copolymers existed as “core–shell”spheres at an elevatedtemperature, as a result of the self-assembly of the agarose backboneslocated in the “core” driven by hydrogen-bonding interactions.When the copolymer solution was cooled below UCST, the core–shellspheres began to aggregate because of the electrostatic interactionsand collapse of PDMAPS side chains in the “shell” layer.UCST of the copolymer could be tuned in a wide range, depending onthe chain lengths of PDMAPS. This is the first example to investigatethe thermosensitivity, combining ionic interactions of the zwitterionicside chains with hydrogen bondings from the biocompatible agarosebackbones. The synthetic strategy presented here can be employed inthe preparation of other novel biomaterials from a variety of polysaccharides. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the roles of the phospholipases A2 (PLA2) subtypes, iPLA2-VIA and sPLA2-IB in retinal pigment epithelium (RPE) phagocytosis of photoreceptor outer segments (POS) and to explore a possible interaction between sPLA2-IB and iPLA2-VIA in the RPE. Methods: To explore the role of iPLA2-VIA in RPE phagocytosis of POS, experiments with iPLA2-VIA vector transfection, iPLA2-VIA−/− knockout (KO) mice, and iPLA2-VIA inhibition by bromoenol lactone (BEL) were done. Exogenous addition of sPLA2-IB was used to investigate the role of sPLA2-IB in RPE phagocytosis. A Luciferase Reporter Vector containing the iPLA2-VIA promoter was used to study the effects of sPLA2-IB on the iPLA2-VIA promoter. Results: ARPE-19 and primary mouse RPE cells transfected with iPLA2-VIA showed increased phagocytosis. Phagocytosis was reduced in primary mouse RPE inhibited with BEL and in RPE from KO mice. Exogenous addition of enzymatically active and inactive sPLA2-IB reduced phagocytosis in ARPE-19 and primary mouse RPE cells. Finally, sPLA2-IB did not seem to affect the iPLA2-VIA promoter. Conclusion: The present study confirms the involvement of iPLA2-VIA in efficient RPE phagocytosis of POS, while exogenously added sPLA2-IB decreases phagocytosis regardless of enzymatic activity. No apparent interaction between iPLA2-VIA and sPLA2-IB was found. [ABSTRACT FROM AUTHOR]

Abstract: Hydrothermal cooking (HTC) combined with amylase pretreatment (AP) was used to improve protein extraction from heat-stabilized rice bran. The physicochemical and emulsifying properties of rice bran protein isolate (RPI) were evaluated. Depending on HTC temperature (120 and 150°C), HTC alone significantly increased extraction yield, while protein purity was decreased. In contrast, HTC combined with AP significantly improved both extraction yield and protein purity (about 45–50% and 72–74%, respectively). The AP avoided the co-precipitation of gelatinized starch during the acidic precipitation. Electrophoresis and size exclusion chromatography profiles indicated that HTC led to the dissociation of insoluble protein aggregates in rice bran, with subsequent increase of soluble aggregates in RPI, linked by non-covalent (e.g., hydrophobic interaction) and covalent bonds (disulfide bond). This result was evidenced by the increased disulfide bond contents and surface hydrophobicity of RPI. In addition, HTC-prepared RPI exhibited excellent emulsifying property. [Copyright &y& Elsevier]

The carbon nanotubes (CNTs) is modified with a acids treated processing to shorten the length of CNTs, increase reactive groups especially the carboxyl on the surface of CNTs, and improve the dispersion in aqueous solution. The structure and groups of CNTs were determined with the SEM, FTIR and XPS. the synthesis of polyaniline nanotubes was taken by use of the template and reactor of CNTs, show the good nanometer-size and tuber crystalline structure by the anlysis of TG, DSC and UV/Vis. Moreover, the room-temperature conductivities of the synthesized polyaniline nanotubes are 0.6 S/cm, much higher than that of the common amorphous granular polyaniline. [ABSTRACT FROM AUTHOR]

. Purpose: Cyclooxygenase-2 (COX-2) is an enzyme involved in neoplastic processes. The purpose of the present study is to investigate COX-2 expression in the normal human eye and the expression pattern in selected eye tumours involving COX-2 expressing cells. Methods: Immunohistochemical staining using antibodies against COX-2 was performed on paraffin sections of normal human eyes and selected eye tumours arising from cells expressing COX-2. Results: Cyclooxygenase-2 expression was found in various structures of the normal eye. Abundant expression was seen in the cornea, iris, ciliary body and retina. The COX-2 expression was less in tumours deriving from the ciliary epithelium and also in retinoblastoma. Conclusion: Cyclooxygenase-2 is constitutively expressed in normal human eyes. The expression of COX-2 is much lower in selected eye tumours involving COX-2 expressing cells. [ABSTRACT FROM AUTHOR]

Abstract: Pseudomonas fluorescens BIT-18 was isolated from soil near a vegetable oil factory and shown to produce a B-type phospholipase. The enzyme was partially purified by ammonium sulfate precipitation. Gas chromatography demonstrated that the enzyme preparation hydrolyzed both the 1- and 2-ester bonds of phosphatidylcholine. When degumming of soybean, rapeseed, and peanut oil was performed with this enzyme preparation, oils with phosphorous contents lower than 5mg/kg were obtained after 5h of enzyme treatment at 40°C. The enzyme preparation did not show lipase activity, thus free fatty acids were only generated from the phospholipids. Therefore, this novel phospholipase B is potentially useful for the refining of high-quality oils with attractive yields. [Copyright &y& Elsevier]

Abstract: High-quality c-axis oriented delafossite-type CuCrO2 films were successfully prepared by a simple sol–gel method. The microstructure, optical properties as well as room temperature resistivity were studied. It was found that the grain sizes of CuCrO2 films pretreated with different temperatures are different; the films were smooth and consisted of fine particles. The maximal transmittance of CuCrO2 films can reach 70% in the visible region. Optical transmission data of CuCrO2 films indicate a direct band gap and an indirect-gap of about 3.15eV and 2.66eV, respectively. The carrier mobility of the films pretreated at 300°C is smaller than that of the films pretreated at a higher temperature, because of the stronger carrier scattering. [Copyright &y& Elsevier]

Abstract: Phospholipases A2 (PLA2s) and its generation of second messengers play an important role in signal transduction, cell proliferation, cell survival and gene expression. At low concentrations mediators of PLA2 activity have a variety of physiological effects whereas high levels of PLA2 and its metabolites are generated during pathological conditions. The eye is an immunoprivileged organ with tight barriers and a complex interplay among various cell types. Overall, vision is a complex process which requires a clear corneal surface and lens, and thereby a clear pathway through the eye into the retina. In the retina the photoreceptors transmit light into neuronal signals that are finally transferred to the brain to perceive an image. Growing knowledge of a role of PLA2 in ocular diseases appears and the present review aims to summarize the vast literature on PLA2 in the normal eye as well as during pathological conditions. [Copyright &y& Elsevier]

In this paper, SD rat constipation model was established with loperamide hydrochloride to study the effect of Chrysanthemum morifolium polysaccharide on the improvement of functional constipation, and the mechanism of improving constipation was investigated with the proteomics and intestinal flora. The results showed that the HD group of C. morifolium polysaccharide could significantly increase the levels of water content of stool pellets, small intestine propulsion rate, gastrin (MTL), gastrin (GAS) and substance P (SP), decrease the level of growth inhibitor (SS) and improved gastrointestinal motility in rats. Gut microbial studies showed that C. morifolium polysaccharide could significantly increase species abundance and flora diversity and improve flora structure. The relative abundance of Lactobacillus and Romboutsia increased, while the relative abundance of Lachnospiraceae_NK4A136_group and Roseburia decreased compared with the MC group. Proteomics studies suggested that C. morifolium polysaccharides could reduce intestinal lesions, enhance intestinal homeostasis, increase amino acid uptake, promote intestinal motility and relieve constipation by regulating the expression of RAS, FABP1 and SLC1A5 proteins. [ABSTRACT FROM AUTHOR]

A novel atmospheric-pressure plasma source has been developed to determine metal ions in an aqueous solution by means of optical emission spectroscopy. In contrast to the conventional solution cathode glow discharge, this plasma source is sustained by a milli-second pulsed power supply. The electrical characteristics and spectral characteristics of the proposed plasma source are discussed. The effects of operating parameters, including pulse excitation and maintenance discharge voltage, pulse width, pulse modulation duty ratio, solution flow rate, and detector delay time, are investigated. Na, K, and Ca were observed to have a cumulative spectral emission time of 250 μs. Delayed acquisition times (in the case of maximum spectral intensity) are 500, 800, 800, 900, and 900 μs, respectively for Cu, Co, Cd, Mn, and Ag. The detection limits of trace elements such as Na, K, Cu, Co, Cd, Mn, and Ag were 0.080, 0.050, 3.4, 64, 69, 9.1, and 2.0 μg L−1, respectively. Compared to DC-excited solution cathode glow discharge, the detection performance of the above elements is observed to be increased by 2.9, 1.5, 18, 5.5, 25, 1.6, and 2.1 times, respectively. The proposed excitation source provides a promising method for detecting metal ions in aqueous solution samples. [ABSTRACT FROM AUTHOR]

Summary: In this work, soy protein isolates (SPIs) were subjected to microparticulation, turning soy protein ingredients into microparticles with improved thermal stability which could be used in high‐protein foods. The pH is a critical determinant in microparticulation. Our work is mainly to investigate the effect of pH on the formation and properties of protein microparticles. To clarify the effects of pH conditions on the properties of the resulting particles, microparticulation was performed at different pH conditions (7.0, 6.0 and 5.0). Aggregation behaviours described by the parameters calculated from the protein dispersion viscosity combined with the observation of the morphology change were used to analyse the particle formation process. For the microparticles prepared at pH 5.0, soy proteins were more inclined to aggregate into clusters on a micro‐scale which had a flexible conformation. After spray drying, This powder could be easily dispersed in water, creating a dispersion with a protein concentration of 10 wt%. At this concentration, the thermal gelation capacity of the proteins was observed to decrease. Conversely, the tendency of protein aggregation was largely restricted when soy protein microparticulation was carried out at pH 7.0. As these soy protein particles in nano‐scale were dispersed in water, a decrease rather than an increase was recorded in the viscosity of this dispersion after it was heated, suggesting that these particles had improved thermal stability. This work has demonstrated that implementing appropriate pH conditions during microparticulation can prepare soy protein particles with different sizes and rheological properties, which might meet the demands of various food processing. [ABSTRACT FROM AUTHOR]

The direct determination of analytes in aqueous solution using laser-induced breakdown spectroscopy (LIBS) has several difficulties, including low spectral signal, poor stability, and rapid quenching of the plasma. In this study, chelate resin and anion exchange resin were used to adsorb the chromium ions Cr(III) and Cr(VI) from the liquid onto a solid substrate, thus avoiding the drawbacks of liquid analysis with LIBS. Cr(III) and Cr(VI) were separated by selective adsorption on these two distinct resins. The following analytical parameters were optimized: flow rate of sample solution for preconcentration on the resins, laser pulse energy, and integral delay time of the ICCD detector. Calibration curves displayed excellent linearity, with correlation coefficients of 0.994 for Cr(III) and 0.993 for Cr(VI). The analytical limits of detection (LODs) were 0.088 mg L−1 for Cr(III) and 0.27 mg L−1 for Cr(VI), and were lower than those in most previous studies. The relative uncertainty of Cr(III) in single and mixed solutions ranged from 2.50% to 4.25% and 4.75% to 14.0%, respectively, and that of Cr(VI) ranged from 2.88% to 7.67% and 11.5% to 13.9%, respectively. Recovery from natural spring water was 92.50–99.86% for Cr(III) and 97.70–98.75% for Cr(VI). Recovery from sewage wastewater using this method was 99.80% for Cr(III) and 107.6% for Cr(VI). These results show that this method can be successfully applied to the determination and separation of chromium ions in aqueous solution. [ABSTRACT FROM AUTHOR]

In this paper, Nb-doped TiO 2 films were fabricated on ITO glass substrates by dip coating using tetrabutyl titanate as the starting material, niobium chloride as the dopant, acetylacetone as the chelating agent and methanol as the solvent. The effects of Nb doping on the microstructure and electrochromic properties have been studied. The results reveal that a simultaneous regulation of near-infrared (NIR) and visible light in pure TiO 2 films can be achieved by applying the electrochemical voltage, while Nb-doped TiO 2 films demonstrate the ability of selective and independent optical transmittance modulation in both regions. Varying the applied electrochemical voltage over a range of 3.5 V makes these Nb-doped TiO 2 films undergo two electrochromic processes. One is local surface plasma resonant (LSPR) electrochromic process, and the other is redox electrochromism. These two electrochromic effects result in a unique optical switching behavior that is the reversible switching of "bright and warm" - "bright and cool" - "dark and cool" modes. Therefore, this kind of materials enables the dynamic control of solar radiation transmittance through windows. Furthermore, the higher the amount of Nb dopant is, the stronger the LSPR electrochromism is. Finally, the enhanced LSPR improves the redox electrochromism of Nb-doped TiO 2 films, resulting in a higher dual-band electrochromic performance in NIR and visible regions. [ABSTRACT FROM AUTHOR]

The article offers information on the chemical composition Caragana sinica, a species belonging to the genus Caragana. Among the composition of Caragana include β,-Sitosterol, ursolic acid, and α-amyri. It discussses the use of Caragana as folk medicines for treating vascular hypertension, asthenia syndrome, leukorrhagia, dizziness and tinnitus in China.

In this study, a refrigerating anode method was developed to improve solution cathode glow discharge-atomic emission spectrometry (SCGD-AES) for the determination of elements. Spectral characteristics of metal anodes at different temperatures were studied in the range from 10 to 30 °C. The spectral signals of metals were enhanced by reducing the metal anode temperature during the plasma discharge. Moreover, the method of the refrigerating anode improved the stability of spectral emission of metal elements. Compared with the unrefrigerated system under the same experimental conditions, the detection limits of Ag, Cd, Cu, Mn and Zn were 0.6, 9.1, 5.3, 8.7 and 16 μg L−1, respectively, which represented the improvements by 6.5, 3.5, 3.2, 3.9 and 3.1 times, respectively. The measurement results of Ag, Cd, Cu, Mn and Zn in a certified reference solution (BWB2446-2016) and an actual water sample from the Yangtze river by SCGD-AES with the refrigerating anode were in agreement with the reference values measured by ICP-OES. The water sample recovery from the Yangtze river ranged from 101.5 to 110.0%, suggesting that the measurement results exhibited high accuracy and reliability. All the results indicated that SCGD-AES coupled with a refrigerating anode could improve its analytical ability and provide an analytical method for in situ, real-time and on-line determination of metal elements in water samples. [ABSTRACT FROM AUTHOR]

Antibiotics, such as tetracycline hydrochloride (TC), are persistent pollutants in the environment due to their difficult degradation properties. In this study, a MoS2/ZnO heterostructure nanocomposite was synthesized and evaluated for its photocatalytic performance in degrading TC under simulated sunlight irradiation. The degradation rate of TC in the MoS2/ZnO/PMS system reached 99.8% after 30 min, surpassing the rates observed in both ZnO and MoS2/ZnO systems. The presence of active species, including superoxide radicals (˙O2−), hydroxyl radicals (˙OH), sulfate (SO4˙−) and singlet oxygen (1O2), was confirmed through trapping experiments and electron paramagnetic resonance (ESR) analysis. The MoS2/ZnO heterostructure effectively suppressed the recombination of photogenerated charge carriers, leading to improved photocatalytic efficiency. The results demonstrate the potential of the MoS2/ZnO/PMS system as a low cost and efficient method for the removal of TC from water. This study contributes to the development of photocatalytic materials for the degradation of persistent organic pollutants in aqueous environments. [ABSTRACT FROM AUTHOR]

Summary: Soy protein‐gum Arabic (GA) core‐shell nanoparticles were fabricated as carriers for hydrophobic phytosterol (PS) using an anti‐solvent precipitation (pH 7.0) and then coating GA on the surface of protein‐based PS nanoparticles at pH 4.5. PS nanoparticles stabilised by heat‐treated soy protein isolate (SPI), especially subcritical water‐treated SPI (SW, 120 °C), exhibited higher encapsulation efficiency (EE), loading amount (LA) and colloidal stability than native SPI‐stabilised PS nanoparticles. The highly flexible conformation and more exposed hydrophobic clusters of SW‐treated SPI could result in a quick encapsulation of more PS into the interior of protein molecules during anti‐solvent precipitation. However, for native SPI with rigid globular structure, the loading of PS mainly occurred on the surface hydrophobic sites of protein molecules. After introducing GA (≥5 mg mL−1) to PS nanoparticles fabricated by SW‐treated SPI, submicron‐sized (Dh 250.71~341.76 nm) core‐shell nanoparticles with high acid solubility and thermal stability were formed. The coating of GA decelerated the digestion of SW‐treated SPI, and improved the EE, LA and in vitro bioaccessibility of PS under acidic environment. These results reveal the protein structure dependence of PS encapsulation and provide a simple approach to fabricate biopolymer‐based nanoparticle delivery system for hydrophobic bioactives in acidified functional drinks. [ABSTRACT FROM AUTHOR]

Ferrous iron (Fe(II)) is essential to organisms, but ferric iron (Fe(III)) is toxic. Monitoring Fe(II) and Fe(III) in solution can improve our understanding of Fe biogeochemistry and toxicity. However, it is difficult to rapidly determine Fe in different valence states in solution using traditional methods. A novel method, laser-induced breakdown spectroscopy coupled with chelating resin selective enrichment by adjusting the solution pH, for determining Fe(II) and Fe(III) in solution is presented here. The sample solution flow rate and solution pHs were optimized to obtain a better enrichment effect. The calibration curve for Fe(II) and Fe(III) were established and the limits of detection were 0.120 mg L−1 and 0.142 mg L−1, respectively. Single valence state Fe in an Fe(II) and Fe(III) mixed solution was separated based on the enrichment abilities of Fe(II) and Fe(III) at different pH values of the chelating resin, and the separation relative error ranges were 0.25%–1.12% and 3.05%–7.24%, respectively. The recoveries of Fe(II) and Fe(III) in real spring water were 100.62% and 99.11%, respectively. The results indicated that the method of LIBS coupled with chelating resin selective enrichment can rapidly and accurately quantify Fe in different valence states in aqueous solution. [ABSTRACT FROM AUTHOR]

A hollow anode-solution cathode glow discharge (HA-SCGD) was designed as a plasma excitation source for optical emission spectrometry. The operation parameters such as the discharge current, argon flow rate and solution flow rate were investigated. The spatial distribution profiles of normalized results of spectral bands and spectral lines were investigated and analyzed. The detection limits of Na, Li, K, Ca, Mg, Pb, Sr, Mn, Rb, Cs and Zn were 0.22, 0.69, 1.33, 240.37, 21.55, 529, 619.43, 209.51, 2.94, 7.13 and 206.95 µg L−1, respectively. The repeatability, expressed as the relative standard deviation for these elements, was determined to be within the range from 0.53 to 2.70%. The Ca, Fe, K, Mg and Na concentrations in a certified reference material were quantitatively analyzed, and the results obtained by the HA-SCGD system agreed well with the reference values. The results show that the HA-SCGD system accurately and stably determined metals in aqueous solution. [ABSTRACT FROM AUTHOR]

Solution cathode glow discharge-atomic emission spectrometry (SCGD-AES) has attracted wide attention globally in recent years. The technology has the advantages of on-line detection of various metal elements, small volume, and convenience. In this work, the original spectrometer based on SCGD-AES technology was replaced by filter-wheel, photomultiplier tube (PMT) and picoammeter, which was named FPP spectral discrimination device. Analytical performance of the device with narrow-band monochromator (0.08 nm) was compared to its performance with wide-bandpass filters (10 nm) with optimized spatial. The relative standard deviation of SCGD-FPP for Na, K, Ca, Li, Sr, Rb, and Cs ranged from 0.2 to 0.8%, comparable to the 0.6 to 1.4% with the monochromator. With optimized spatial resolution, the detection limits ranged from 0.15 to 350 μg/L, and the optimal plasma spectral collected points of Na, K, Ca, Li, Sr, Rb, and Cs at 0.8 mm, 0.8 mm, 0.6 mm, 0.4 mm, 0.2 mm, 0.6 mm, and 0.6 mm, respectively. The deviation analysis of the samples containing Na, K, Ca, and Li were analyzed under optimal conditions. The results show that a SCGD-FPP source with spatial resolution improved the detection performance. [ABSTRACT FROM AUTHOR]

[Display omitted] Oral lichen planus (OLP) is a T cell-mediated autoimmune disease of oral mucosa concerning with the redox imbalance. Although glutamine uptake mediated by alanine-serine-cysteine transporter 2 (ASCT2) is critical to T cell differentiation, the exact mechanism remains ambiguous. Here, we elucidate a novel regulatory mechanism of ASCT2-mediated uptake in the differentiation and proliferation of T cells through maintaining redox balance in OLP. The results of immunohistochemistry (IHC) showed that both ASCT2 and glutaminase (GLS) were obviously upregulated compared to controls in OLP. Moreover, correlation analyses indicated that ASCT2 expression was significantly related to GLS level. Interestingly, the upregulation of glutamine metabolism in epithelial layer was consistent with that in lamina propria. Functional assays in vitro revealed the positive association between glutamine metabolism and lymphocytes infiltration. Additionally, multiplex immunohistochemistry (mIHC) uncovered a stronger colocalization among ASCT2 and CD4 and IFN-γ, which was further demonstrated by human Th1 differentiation assay in vitro. Mechanistically, targeting glutamine uptake through interference with ASCT2 using L-γ-Glutamyl-p-nitroanilide (GPNA) decreased the glutamine uptake of T cells and leaded to the accumulation of intracellular reactive oxygen species (ROS), which promoted dual specificity phosphatase 2 (DUSP2/PAC1) expression through activation of early growth response 1 (EGR1) to induce dephosphorylation of signal transducer and activator of transcription 3 (STAT3) and inhibit Th1 differentiation in turn. These results demonstrated that glutamine uptake mediated by ASCT2 induced Th1 differentiation by ROS-EGR1-PAC1 pathway, and restoring the redox dynamic balance through targeting ASCT2 may be a potential treatment for T cell-mediated autoimmune diseases. [ABSTRACT FROM AUTHOR]