The endosymbiont Serratia symbiotica improves aphid fitness by disrupting the predation strategy of ladybeetle larvae.

Aphids, the important global agricultural pests, harbor abundant resources of symbionts that can improve the host adaptability to environmental conditions, also control the interactions between host aphid and natural enemy, resulting in a significant decrease in efficiency of biological control. The facultative symbiont Serratia symbiotica has a strong symbiotic association with its aphid hosts, a relationship that is known to interfere with host-parasitoid interactions. We hypothesized that Serratia may also influence other trophic interactions by interfering with the physiology and behavior of major predators to provide host aphid defense. To test this hypothesis, we investigated the effects of Serratia on the host aphid Acyrthosiphon pisum and its predator, the ladybeetle Propylaea japonica. First, the prevalence of Serratia in different A. pisum colonies was confirmed by amplicon sequencing. We then showed that harboring Serratia improved host aphid growth and fecundity but reduced longevity. Finally, our research demonstrated that Serratia defends aphids against P. japonica by impeding the predator's development and predation capacity, and modulating its foraging behavior. Our findings reveal that facultative symbiont Serratia improves aphid fitness by disrupting the predation strategy of ladybeetle larvae, offering new insight into the interactions between aphids and their predators, and providing the basis of a new biological control strategy for aphid pests involving the targeting of endosymbionts.

Surface engineering of Al2O3 nanotubes by ureasolysis method for activating persulfate degradation of antibiotics.

Though ecofriendly, pure Al2O3 has never been used for activation of peroxodisulfate (PDS) to degrade pollutants. We report the fabrication of Al2O3 nanotubes by ureasolysis method for efficient activating PDS degradation of antibiotics. The fast ureasolysis in aqueous AlCl3 solution produces NH4Al(OH)2CO3 nanotubes, which are calcined to porous Al2O3 nanotubes, and the release of ammonia and carbon dioxide engineers the surface features of large surface area, numerous acidic-basic sites and suitable Zeta potentials. The synergy of these features facilitates the adsorption of the typical antibiotics ciprofloxacin and PDS activation, which is proved by experiment results and density functional theory simulation. The proposed Al2O3 nanotubes can catalyze 92-96% degradation of 10 ppm ciprofloxacin within 40 min, with chemical oxygen demand removal of 65-66% in aqueous, and 40-47% in whole including aqueous and catalysts. Ciprofloxacin at high concentration, other fluoroquinolones and tetracycline can also be effectively degraded. These data demonstrate the Al2O3 nanotubes prepared by the nature-inspired ureasolysis method has unique features and great potentials for antibiotics degradation.

Effect of honeysuckle leaf extract on the physicochemical properties of carboxymethyl konjac glucomannan/konjac glucomannan/gelatin composite edible film.

Honeysuckle leaves are rich in bioactive ingredients, but often considered as agro-wastes. In this study, honeysuckle leaf extract (HLE) was added to the carboxymethyl konjac glucomannan/konjac glucomannan/gelatin composite edible film (CMKH). Compared to films without HLE addition (CMK), the water vapor barrier properties of CMKH slightly decreased, but the transmittance of the CMKH films in UV region (200-400 nm) as low as zero. The elongation at break of CMKH film was 1.39 âˆ¼ 1.5 fold higher than those of CMK films. The DPPH and ABTS scavenging activity of CMKH-Ⅱ was 85.75% and 90.93%, respectively, which is similar to the equivalent content of Vc. The inhibition rate of CMKH-Ⅰ and CMKH-Ⅱ against Escherichia coli and Listeria monocytogenes were close to 90%, and the inhibition rate against Staphylococcus aureus were up to 96%. The results emphasized that the composite film containing 25% (v/v) HLE has potential application value in food preservation.

Simultaneously enhanced stability and biological activities of chlorogenic acid by covalent grafting with soluble oat ß-glucan.

Chlorogenic acid (CA) has a wide range of biological activities but the chemical structure is extremely unstable. In this study, CA was grafted onto a soluble oat ß-glucan (OßGH) to improve the stability. Although the crystallinity and thermal stability of CA-OßGH conjugates reduced, the storage stability of CA significantly improved. The DPPH and ABTS scavenging ability of CA-OßGH IV (graft ratio 285.3 mg CA/g) were higher than 90 %, which is closed to activities of equivalent concentration of Vc (93.42 %) and CA (90.81 %). The antibacterial abilities of CA-OßGH conjugates are improved compared to the equivalent content of CA and potassium sorbate. Particularly, the inhibition rate of CA-OßGH for gram-positive bacteria (Staphylococcus aureus and Listeria monocytogenes) are significantly higher than that of gram-negative bacteria (Escherichia coli). The results demonstrated that covalent grafted CA with soluble polysaccharide is an effective strategy to enhance its stability and biological activities.

Cr3+-ZnGa2O4@Pt for Light-Triggered Dark Catalytic Regeneration of Nicotinamide Coenzymes without Other Electron Mediators.

Photocatalysts for regeneration of reduced nicotinamide adenine dinucleotide (NADH) usually work with continuous lighting and electron mediators, which causes impracticability under dark conditions, risk of NADH reoxidation, and complex separation. To solve these problems, we present a new catalyst of tiny Pt nanoparticles photodeposited on chromium-doped zinc gallate (CZGO@Pt). Upon being light-triggered, the photogenerated electrons are stored in the traps of CZGO and then gradually released and transferred by Pt to directly reduce NAD+ after stoppage of illumination. Three lighting modes are compared to demonstrate the feasibility and advantage of this light-triggered dark catalysis. Within 4 h of reaction, the in-the-dark NADH yield reaches 75.0% under prelighting CZGO@5%Pt and it reaches 80.0% under prelighting CZGO@5%Pt and triethanolamine (TEOA). However, the NADH yield is only 53.5% under continuous lighting of CZGO@5%Pt, TEOA, and NAD+. Consequently, the light-triggered dark catalytic regeneration of NADH not only saves energy and operates easily but also significantly elevates the NADH yield. It thus would secure wide interests and applications in places where no light or only intermittent light is available.

Porous Ga2 O3 Nanotubes Derived from Urease-Mediated Interfacially-Grown NH4 Ga(OH)2 CO3 for High-Efficient Hydrogen Evolution.

The authors proposed a novel template-free strategy, urease-mediated interfacial growth of NH4 Ga(OH)2 CO3 nanotubes at 20-50 °C, to fabricate the porous Ga2 O3 nanotubes. The subtlety of the proposed strategy is all the products from urea enzymolysis are utilized in formation of NH4 Ga(OH)2 CO3 precipitates, and the key for interfacial growth of NH4 Ga(OH)2 CO3 nanotubes is the dynamic match between the rate of CO2 bubble fusion and NH4 Ga(OH)2 CO3 precipitation. The proposed strategy works well for the doped porous Ga2 O3 nanotubes. As a proof-of-concept, the porous ß-Ga2 O3 and ß-Ga2 O3 :Cr0.001 nanotubes are used as photocatalysts or co-catalysts with Pt, for H2 evolution from water splitting. The H2 evolution rate of porous ß-Ga2 O3 nanotubes reach 39.3 mmol g-1 h-1 with solar-to-hydrogen (STH) conversion efficiency of 2.11% (Hg lamp) or 498 µmol g-1 h-1 with STH of 0.03% (Xe lamp) respectively, both about 3 times of ß-Ga2 O3 nanoparticles synthesized at pH 9.0 without urease. The Cr-doping enhances the in-the-dark H2 evolution rate pre-lighted by Hg lamp, and Pt co-catalysis further elevates the H2 evolution rate, for instance, the H2 evolution rate of Pt-loaded ß-Ga2 O3 :Cr0.001 nanotubes reaches 54.7 mmol g-1 h-1 with STH of 2.94% under continuous lighting of Hg lamp and 1062 µmol g-1 h-1 in-the-dark.

Involvement of clathrin-dependent endocytosis in cellular dsRNA uptake in aphids.

RNAi is an essential technology for studying gene function in eukaryotes, and is also considered to be a potential strategy for pest control. However, the mechanism behind the cellular uptake of dsRNA in aphids, a group of important agricultural sucking pests, remains unknown. Here, using the pea aphid Acyrthosiphon pisum as model for aphids, we identified two core genes of clathrin-dependent endocytosis (CDE), Apchc and Apvha16. We confirmed that expression of Apchc, Apvha16 and RNAi core component genes (ApAgo2, ApDcr2 and ApR2d2) were simultaneously induced at 12 h after feeding dsRNA. By using an RNAi-of-RNAi approach, we demonstrated that suppression of Apchc and Apvha16 transcripts by RNAi significantly impaired RNAi efficiency of selected reporter genes (RGs), including ApGNBP1, Apmts and Aphb, suggesting the involvement of CDE in cellular dsRNA uptake in aphids. Further confirmation was also provided using two inhibitors, chlorpromazine (CPZ) and bafilomycin A1 (BafA1). Administration of CPZ and of BafA1 both led to an impaired silencing efficiency of the RGs in the pea aphid. Finally, these RNAi-of-RNAi results were reconfirmed in the peach aphid Myzus persicae. Taking these findings together, we conclude that CDE is involved in cellular dsRNA uptake in aphids.

Aminosilanized magnetic carbon microspheres for the magnetic solid-phase extraction of bisphenol A, bisphenol AF, and tetrabromobisphenol A from environmental water samples.

Aminosilanized magnetic carbon microspheres as a novel adsorbent were designed and fabricated. The adsorbent was used for the magnetic solid-phase extraction of bisphenols at trace levels from environmental water samples before liquid chromatography with tandem mass spectrometry analysis. The structure, surface, and magnetic behavior of the as-prepared aminosilanized magnetic carbon microspheres were characterized by elemental analysis, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, powder X-ray diffraction, and vibrating sample magnetometry. The effects of the experimental parameters were investigated by the Plackett-Burman design, and then the parameters that were significant to the extraction efficiencies were optimized through a response surface methodology. The aminosilanized magnetic carbon microspheres exhibited high adsorption efficiency and selectivity for bisphenols. Under optimal conditions, low limits of detection (0.011-2.22 ng/L), and a wide linear range (2-3 orders of magnitude), good repeatability (4.7-7.8%, n = 5), and reproducibility (6.0-8.3%, n = 3) were achieved. The results demonstrate that the novel adsorbent possesses great potentials in the determination of trace levels of bisphenols in environmental water samples.

[Rapid identification of Coix seed varieties by near infrared spectroscopy].

Unsupervised learning algorithm-principal component analysis (PCA), and supervised learning algorithm-learning vector quantization (LVQ) neural network and support vector machine (SVM) were used to carry out qualitative discriminant analysis of different varieties of coix seed from different regions. Since nutrient compositions of different varieties coix seed samples from different origins were complex and the contents were similar, characteristic variables of two kinds of coix seed were alike, the scores plot of their principal components seriously overlapped and the categories of coix seed were difficult to distinguish While satisfactory results were obtained by LVQ neural network and SVM. The accuracy of LVQ neural network prediction is 90. 91%, while the classification accuracy of SVM, whose penalty parameter and kernel function parameter were optimized, can be up to 100%. The results show that NIRS combined with chemometrics can be used as a rapid, nondestructive and reliable method to identify coix seed varieties and provide technical reference for market regulation.

Robust decentralized hybrid adaptive output feedback fuzzy control for a class of large-scale MIMO nonlinear systems and its application to AHS.

This paper presents a novel observer-based decentralized hybrid adaptive fuzzy control scheme for a class of large-scale continuous-time multiple-input multiple-output (MIMO) uncertain nonlinear systems whose state variables are unmeasurable. The scheme integrates fuzzy logic systems, state observers, and strictly positive real conditions to deal with three issues in the control of a large-scale MIMO uncertain nonlinear system: algorithm design, controller singularity, and transient response. Then, the design of the hybrid adaptive fuzzy controller is extended to address a general large-scale uncertain nonlinear system. It is shown that the resultant closed-loop large-scale system keeps asymptotically stable and the tracking error converges to zero. The better characteristics of our scheme are demonstrated by simulations.

The complex action recognition via the correlated topic model.

Human complex action recognition is an important research area of the action recognition. Among various obstacles to human complex action recognition, one of the most challenging is to deal with self-occlusion, where one body part occludes another one. This paper presents a new method of human complex action recognition, which is based on optical flow and correlated topic model (CTM). Firstly, the Markov random field was used to represent the occlusion relationship between human body parts in terms of an occlusion state variable. Secondly, the structure from motion (SFM) is used for reconstructing the missing data of point trajectories. Then, we can extract the key frame based on motion feature from optical flow and the ratios of the width and height are extracted by the human silhouette. Finally, we use the topic model of correlated topic model (CTM) to classify action. Experiments were performed on the KTH, Weizmann, and UIUC action dataset to test and evaluate the proposed method. The compared experiment results showed that the proposed method was more effective than compared methods.

Soluble dietary fiber from Canna edulis Ker by-product and its physicochemical properties.

Using Canna edulis Ker by-product as raw materials, soluble dietary fiber (SDF) was prepared using six different methods, including chemical, physical-chemical, enzymatic, physical-enzymatic, chemical-enzymatic and physical-chemical-enzymatic methods. As main component in the C. edulis by-product composed of cellulose, glucose converts to other single sugars, which form a series of compounds in the SDF. The treated methods have impact effects on single sugar composition, metal ion content, molecular size distribution, chemical bonds and groups in the structure, thermal property and color of the final product. In view of security, high yield and homogeneity as well as good thermal stability of final product, physical-enzymatic method will be a best choice for the production of SDF from C. edulis by-product. The SDF obtained can be used as dietary supplement and additive in the food industry.

Canna edulis Ker by-product: chemical composition and characteristics of the dietary fiber.

Canna edulis Ker by-product was recycled and utilized after starch extraction. The chemical composition, physical properties and antioxidant activity of the by-product were investigated. The by-product was mainly composed of dietary fiber (54.84% measured by AOAC method), and the insoluble dietary fiber constituted the major fraction. Then, the chemical composition of dietary fiber was tested using modified AOAC and Englyst methods. The results showed that dietary fiber was comprised of cellulose, hemicelluloses (including xyloglucans, arabinoxylans and glucuronoxylans), pectin and lignin. Moreover, the by-product contained relatively high content of phenolic compounds and exhibited a moderate antioxidant activity. In addition, the by-product showed both high water-holding capacity (12.5 mL/g) and oil-holding capacity (14 mL/g), and its suspension exhibited controllable viscosity. Therefore, the by-product from C. edulis is not only a source of dietary fiber but also a functional ingredient for food industry.

Molecular interaction in binary surfactant mixtures containing alkyl polyglycoside.

Surface tensions were measured for several binary mixtures of a multidegree polymerized alkyl polyglycoside, C12G1.46' with different types of surfactants in 0.1 M NaCl at 25 degrees C. Based on regular solution theory, using a dimensional crystal model and a phase separation model, the molecule exchange energy in mixed monolayer formation (epsilon) and mixed micellization (epsilon(m)) were determined. Surfactants used in the mixtures with C12G1.46 in this study are C12E3S (trioxyethylenated dodecyl sulfonate), C12TAC (dodecyl trimethylammonium chloride), BE-6 (hexaoxyethylenated trisiloxane surfactant), and TMN-6 (hexaoxyethylenated-2,6,8-trimethylnonanol). The mixtures show exchange energy in mixed monolayer formation (epsilon) and mixed micellization (epsilon(m)) ranging from -660 to -1410 J/mol, indicating a decrease in surface energy upon mixing. The decreases in surface energy are in the order C12G1.46/C12E3S > C12G1.46/C12TAC, C12G1.46/C12TAC > C12G2/C12TAC and C12G1.46/BE-6 > C12G1.46/TMN-6. The ability of the mixed monolayer formation relative to the mixed micelle formation of the same binary mixture, measured by the (epsilon-epsilon(m)) values, is in the order C12G1.46/BE-6 > C12G1.46/TMN-6 > C12G1.46/C12E3S-->0 > C12G1.46/C12TAC.

The surface potential of a spherical colloid particle: functional theoretical approach.

By using the iterative method in functional analysis, the potential of the electrical double layer of a spherical colloid particle, which is represented by the so-called Poisson-Boltzmann (PB) equation, has been solved analytically under general potential conditions. With the help of the diagram method in mathematics, the surface potential of the particle has been defined from the second iterative solution. The influence of the parameters included in the solutions on the surface potential has been studied. The results show that the surface potential of the particle increases as the temperature of the system, the aggregation number, and the concentration of ions increase, but decreases with an increase in the dielectric constant and the valence of the ions. The corresponding space charge density also has been illustrated in this work.