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[Objective] To establish methods to determine the content of Aconitine, Yunaconitine, Crassicauline and Vilmorrianine in Aconitun sungpanense Hand-Mazz. and provide scientific basis for its reasonable and safe application. [Methods] Aconitine, Yunaconitine, Crassicauline and Vilmorrianine were used as references. Phenomenex Gemini C18 110A (250 mm ×4.6 mm, 5 [μm); mobile phase; acetonitrile -0.2% acetic acid (pH was regulated to by triethylamine); gradient elute; flow rate; 1 mL/min; UV wavelength 235/254 nm; column temperature; 30 CC. [Results] The content of the 4 Ester-series alkaloids in Aconitun sungpanense Hand. -Mazz. could be determined at the same time. The average recovery rate (n = 6) of Aconitine, Yunaconitine, Crassicauline and Vilmorrianine reached 99. 65% (RSD = 1. 46%), 99. 13% (RSD = 1.32%), 98.13% (RSD =0.98%) and 98.66% (RSD = 1.67%). [Conclusions] The method was simple, accurate and had good repeatability. It could determine the content of Aconitine, Yunaconitine, Crassicauline and Vilmorrianine in Aconitun sungpanense Hand.-Mazz. at the same time. It also provided scientific basis for standardizing the processing of Aconitun sungpanense Hand. -Mazz. and its reasonable and safe application. [ABSTRACT FROM AUTHOR]

Flower color is an important ornamental feature that is often modulated by the contents of flavonoids. Chalcone synthase is the first key enzyme in the biosynthesis of flavonoids, but little is known about the role of R. delavayi CHS in flavonoid biosynthesis. In this paper, three CHS genes (RdCHS1-3) were successfully cloned from R. delavayi flowers. According to multiple sequence alignment and a phylogenetic analysis, only RdCHS1 contained all the highly conserved and important residues, which was classified into the cluster of bona fide CHSs. RdCHS1 was then subjected to further functional analysis. Real-time PCR analysis revealed that the transcripts of RdCHS1 were the highest in the leaves and lowest in the roots; this did not match the anthocyanin accumulation patterns during flower development. Biochemical characterization displayed that RdCHS1 could catalyze p-coumaroyl-CoA and malonyl-CoA molecules to produce naringenin chalcone. The physiological function of RdCHS1 was checked in Arabidopsis mutants and tobacco, and the results showed that RdCHS1 transgenes could recover the color phenotypes of the tt4 mutant and caused the tobacco flower color to change from pink to dark pink through modulating the expressions of endogenous structural and regulatory genes in the tobacco. All these results demonstrate that RdCHS1 fulfills the function of a bona fide CHS and contributes to flavonoid biosynthesis in R. delavayi. [ABSTRACT FROM AUTHOR]

Nickel‐copper‐zinc (NiCuZn) spinel ferrites have attracted intensive research owing to their unique magnetic properties and low co‐fire temperature. Combustion synthesis has been viewed as a promising protocol for the large‐scale fabrication of NiCuZn spinel ferrites. However, the spinel ferrites prepared by this method usually suffer from limited saturation magnetization and high coercivity due to their large size, which will impose detrimental harmonics on electrical equipment (e. g. transformer, motor, etc.). To address these issues, highly porous NiCuZn spinel ferrite hierarchies were prepared within several hours through a modified solution combustion method, using glucose and ammonium nitrate as the fuel and combustion enhancer, respectively. The as‐obtained NiCuZn spinel ferrite hierarchies show excellent magnetic properties with a high saturation magnetization up to 62.61 emu/g and a low coercivity of 9.6 Oe thanks to the rational distribution of cations and grain size. More importantly, this method also allows various modifications (heteroatom doping) and large‐scale applications, which may be promising for the fabrication of high‐performance soft magnets for electrical equipment. [ABSTRACT FROM AUTHOR]

Numerical simulation of free surface multi-fluid flow is a challenging problem owning to the interaction between deformed interface and free surface. In this paper, a multiphase particle solver (free surface multiphase moving particle semi-implicit method, FS-MMPS) is developed to predict the early spreading flow of spilled oil where exist the oil–water interface and air–oil/air–water free surface. First, a multiphase virtual particle model is proposed to substitute the inaccurate free surface boundary condition for multiphase flow in conventional MPS methods. Specifically, virtual particles of different liquid phases are compensated outside free surface so that the pressure of free surface particles can be solved from pressure Poisson equation, thereby improving the accuracy of multi-fluid interaction at free surface. Meanwhile, a pressure gradient model based on the coupling of Taylor series expansion and dynamic specification of particle stabilizing term (PST) is proposed to simultaneously enhance accuracy and depress instability caused by multiphase virtual particles. Experiments of early spreading of thick oil slicks and continuous oil spill from a damaged tank are conducted for validation and demonstration of the accuracy and stability enhancements in 2D. Finally, the effects of traveling wave and continuous spilling on oil spreading are investigated to show the capability of the proposed method. The spreading of thick oil slicks is accelerated when wave height increases or wave length decreases, and the largest increase of spreading rate accelerated by traveling wave is 14%. [ABSTRACT FROM AUTHOR]

The interface microzone characteristics determine the thermophysical properties of diamond/Cu composites, while the mechanisms of interface formation and heat transport still need to be revealed. Here, diamond/Cu-B composites with different boron content were prepared by vacuum pressure infiltration. Diamond/Cu-B composites up to 694 W/(mK) were obtained. The interfacial carbides formation process and the enhancement mechanisms of interfacial heat conduction in diamond/Cu-B composites were studied by HRTEM and first-principles calculations. It is demonstrated that boron can diffuse toward the interface region with an energy barrier of 0.87 eV, and these elements are energetically favorable to form the B4C phase. The calculation of the phonon spectrum proves that the B4C phonon spectrum is distributed in the range of the copper and diamond phonon spectrum. The overlapping of phonon spectra and the dentate structure together enhance the interface phononic transport efficiency, thereby improving the interface thermal conductance. [ABSTRACT FROM AUTHOR]

Multi-view clustering has attracted increasing attention for handling complex data with multiple views or sources. Among them, spectral clustering-based methods become more and more popular due to it can make full use of information from different views. However, most existing multi-view spectral clustering methods typically adopt a two-step scheme, which firstly obtains the spectral embedding matrix through graph fusion or multi-feature fusion, and then uses the k-means algorithm to cluster the spectral embedding matrix to obtain the final clustering result. This two-step scheme inevitably leads to information loss, resulting in a suboptimal solution. Furthermore, the methods of graph fusion and multi-feature fusion have not taken into account the inconsistency of features between different views and the unordered nature of clustering labels, which also decreases the clustering performance. To solve these problems, we propose a novel one-step multi-view spectral clustering based on multi-feature similarity fusion. This model simultaneously conducts graph learning, multi-feature similarity fusion and discretization in a unified framework, which can mutually negotiate and optimize each other to achieve better results. Furthermore, compared to directly fusing affinity matrices or spectral embedding matrixs from different views, we take advantage of the property of the spectral embedding matrix, fuse the similarity of samples in feature space, better handle the differences between different views. Finally, the superiority of our method is verified by the experimental evaluation of several data sets. The demo code of this work is publicly available at https://github.com/kong-de-zheng/MOMSC. [Display omitted] • Introduce block diagonal constraint to make the affinity matrix accurately reflecting the data structure. • Fuse the features from different views, preserving the local structure and the consistency of multi-views. • Propose an one-step framework to optimize graph learning, multi-feature fusion and clustering. [ABSTRACT FROM AUTHOR]

Abstract: Hydrogen production by biomass gasification using solar energy is a promising approach for overcoming the drawbacks of fossil fuel utilization, but the storage of discontinuous solar flux is a critical issue for continuous solar hydrogen production. A continuous hydrogen production system by biomass gasification in supercritical water using molten-salts-stored solar energy was proposed and constructed. A novel double tube helical heat exchanger was designed to be molten salts reactor for hydrogen production. Model compounds (glycerol/glucose) and real biomass (corn cob) were successfully gasified in this molten salts reactor for producing hydrogen-rich gas. The unique temperature profiles of biomass slurry in the reactor were observed and compared with that of conventional electrical heating and direct solar heating approaches. Product gases yield, gasification efficiency and exergy conversion efficiency of the reactor were analyzed. The results showed that the performances of reactor were determined by feedstock style, biomass concentration, residence time and biomass slurry temperature profiles. [Copyright &y& Elsevier]

Copper matrix composites reinforced with 60 vol% diamond particles were prepared by pressure infiltration using Cu-Cr alloy with 0.3–1.0 wt% Cr. The x-ray diffraction, scanning electron microscopy, and transmission electron microscopy were conducted to characterize the Diamond/Cu composites interface. The interface structure evolves from the discontinuous point contact to continuous strip carbides depending on the availability of Cr source. With Cr content increasing, the thermal conductivity of the Diamond/Cu-Cr composites increases first and then decreases. The highest thermal conductivity of 696 W/mK was achieved at 0.5 wt% Cr addition, while the highest tensile strength and bending strength of 252 MPa and 523 MPa were achieved at 0.7 wt% Cr addition. By optimizing the interface thermal resistance and interface bonding strength, Diamond/Cu composites with excellent comprehensive properties can be obtained. [Display omitted] • An interface with low thermal resistance and high strength of Diamond/Cu composites is optimized. • The maximum thermal conductivity of 696 W/mK and the maximum bending strength of 523 MPa were achieved. • The Cr 3 C 2 -Cu interface is in atomic-level contact and chemically bonded. [ABSTRACT FROM AUTHOR]

Having a burnt pot is bothersome in the kitchen, and the carbonized food on it is difficult to clean. Here, burnt starch, which has the advantage of being mechanically robust, was utilized as the carbon material for energy storage applications. Interestingly, 2D amorphous carbon nanosheets (CNs) could be synthesized by simply burning corn starch above a Ni foam. By further coating a CoO/CoF 2 composite film onto the CNs, the hybrid electrode exhibited significant improvement in terms of electron collection efficiency. Benefiting from the synergistic effect of the Co compounds and CNs, the synthesized electrode demonstrated high specific capacitance (12.00 F cm−2 at a current density of 5 mA cm−2), excellent rate capability, and superior cycling stability. Furthermore, three connected symmetric supercapacitors were able to power LED lights for more than 10 min. Therefore, this work provides a new strategy for the fabrication of 2D CN and further applications in supercapacitors. • 2D amorphous carbon nanosheets were introduced by burning starch above Ni foam. • The CoO/CoF 2 compounds were further coated onto carbon nanosheets. • The sample shows a high capacitance of 12.00 F cm−2 and a long cyclic stability. • Three connected symmetric supercapacitor could power the LED lights for more than 10 min. [ABSTRACT FROM AUTHOR]

Copper matrix composites reinforced with bimodal diamond particles were prepared via pressure infiltration. The effects of diamond particles mixing mode on the microstructure and thermal conductivity of the composites were analyzed. The heat flux vector distributions of the composites with or without the secondary diamond were simulated using finite element models based on the experimental microstructure images. The results show that the thermal conductivity of Diamond/Cu composites under different diamond particle mixing schemes all exceeded 700 W/mK. The obtained maximum thermal conductivity of Diamond/Cu composite is 853 W/mK when 25 vol% of secondary diamond particles with a particle size ratio of 10 were introduced. Such a result is explained by the optimization effect of secondary diamond particles on heat conduction channel and interfacial thermal resistance. Furthermore, the simulation results also prove that the introduction of secondary diamond can effectively improve the heat flux conduction along the diamond reinforced phase. Unlabelled Image • Diamond/Cu composites with bimodal diamond particles were fabricated via vacuum pressure infiltration. • The maximum thermal conductivity value of 853 W/mK in Diamond/Cu composites was obtained. • A uniform and continuous strip Cr 3 C 2 about 0.5 μm thick were formed at the interface between the diamond and copper matrix. [ABSTRACT FROM AUTHOR]

The Diamond/Cu composites with bimodal diamond particles reinforced were fabricated by vacuum pressure infiltration. The influence of diamond volume fractions on the microstructure, thermal expansion behaviour, residual Stress and dimensional stability of the composites were investigated by using scanning electron microscopy, X-ray diffraction, Raman spectroscopy and thermal cycling tests. The CTEs of 3.8–5.8 ppm/K at 50 °C were achieved for the Diamond/Cu composites, owing to the high diamond content (63–81.8 vol%) and the strong interfacial bonding strength. The CTEs of Diamond/Cu composites vary by less than 2 ppm/K in the range of 50–300 °C.Thermal cycling tests show that the residual strain of Diamond/Cu composites ranges from 1.6 × 10−4 to 1.0 × 10−4 as the diamond content increases from 63 vol% to 81.8 vol%. Increasing the diamond content introduces higher residual tensile stress, so the total residual strain drops slowly when the diamond content exceeds 72.5 vol%. The results show that an appropriate amount of diamond addition can obtain a coefficient of thermal expansion matching the semiconductor material and a high dimensional stability of Diamond/Cu composites. • Diamond/Cu composites with bimodal diamond were fabricated via vacuum pressure infiltration. • The average CTE of Diamond/Cu composites is 3.8–5.8 ppm/K (50 °C). • The residual strain is lower than 1.6 × 10−4 under different diamond content. [ABSTRACT FROM AUTHOR]

Abstract The microstructure of the oxide dispersion strengthened (ODS) Fe-15Cr ferritic steel with Ti and Zr additions was characterized using transmission electron microscopy (TEM), elemental mapping, synchrotron small angle X-ray scattering (SAXS) and electron backscatter diffraction (EBSD) techniques. The results showed that bimodal grain size distribution in the matrix was observed, which is attributed to the heterogeneous recrystallization process during the Spark Plasma Sintering (SPS). TEM and SAXS results showed that very high density nanoscale oxides are formed in 15Cr-ODS steel. Large concentration of nm-scale trigonal-phase Y 4 Zr 3 O 12 oxides and some large oxides of monoclinic CrTi 2 O 5 are observed in specimen by high resolution TEM (HRTEM) and Energy-dispersive X-ray spectroscopy (EDS) mapping. Finally, the yield stress was experimentally measured and quantitatively estimated. The findings indicated that theoretical calculation was in accordance with the experimental results, and strengthening contributions from solute atoms, grains boundaries, dislocations and oxides was presented. [ABSTRACT FROM AUTHOR]

• A phase field model on MPB with local compositional heterogeneity is developed. • Three-phase mixture forms due to the local compositional heterogeneity. • Polarization rotation under electric fields contribute to the piezoelectricity. • d 33 coefficient decreases due to the on-average more difficult polarization rotation. In this work, the effect of local compositional heterogeneity on the domain structure and piezoelectricity at ferroelectric morphotropic phase boundary (MPB) is studied by phase field simulations. It is found that the local compositional heterogeneity leads to a unique domain structure at MPB, i.e., a mixture of tetragonal, monoclinic and rhombohedral domains. Although polarization rotation occurs for both MPB samples with and without local compositional heterogeneity, the piezoelectric d 33 coefficient becomes reduced for the sample with local compositional heterogeneity because polarization rotation becomes more difficult on average. This work unravels the effect of local compositional heterogeneity on the piezoelectric property of ferroelectric MPB. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nickel-copper-zinc (NiCuZn) ferrites were prepared by a facile blowing-combustion method. • Variation of zinc content with temperature was investigated through inductive coupled plasma (ICP). • The effect of sintering temperatures on structural and magnetic properties of NiCuZn ferrites were investigated. We report the fabrication of nickel-copper-zinc (NiCuZn) ferrites via a facile blowing-combustion method, where the grain size and morphology can be readily controlled by adjusting the sintering temperature. The effect of sintering temperatures on the structural evolution as well as the magnetic properties of the NiCuZn ferrites was systematically studied. It's found that the Zn elemental content is highly dependent on the sintering temperature and would undergo evaporation when annealing at 800 °C, which consequently greatly affects the magnetic properties of NiCuZn ferrites. [ABSTRACT FROM AUTHOR]

Abstract: Direct contact condensation is widely used in industrial applications due to its highly efficient heat and mass transfer. Many experimental and theoretical works have been performed on steam jet condensation in stagnant water in pool. However, the condensation of steam jet in water flow in pipes is not yet fully understood. Here, experiments are performed to study the direct contact condensation of stable steam jet in water flow in a vertical pipe. By using high speed camera and mobile thermocouple probe, we investigate condensation characteristics including the plume shape, plume length, temperature distribution, average heat transfer coefficient, and average Nusselt number. Five different plume shapes (hemispherical, conical, ellipsoidal, cylinder, and divergent) are identified visually, and their distribution is described in a three-dimensional condensation regime diagram based on steam mass flux, water temperature, and Reynolds number of water flow. The dimensionless plume length and average heat transfer coefficient are found to be within the range of 0.29–4.64 and 0.34–11.36MW/m2 K, respectively. Besides, empirical correlations are obtained for the dimensionless plume length, average heat transfer coefficient, and average Nusselt number as a function of three dimensionless parameters, i.e., dimensionless steam mass flux, condensation driving potential, and Reynolds number of water flow. The dimensionless radial temperature decreases exponentially from the center to the pipe wall and shows good self-similarity. [Copyright &y& Elsevier]

Abstract: The inorganic substances precipitate in the reactor for its low solubility in supercritical water, which may influence the performance of supercritical water gasification (SCWG). In the present study, we studied the influence of alkali precipitation on the gasification of glucose with NaOH as catalyst at 500 °C, 25 MPa in a fluidized-bed reactor. The presence of NaOH increased H2 fraction by accelerating water–gas shift reaction and also increased the gas yield. The catalytic effect was further improved with longer reaction time due to the alkali accumulation in the reactor. The precipitated alkali in the reactor still showed high catalytic effect on the subsequent gasification of glucose without further addition of alkali. The catalytic activity was slightly reduced for the transformation of NaOH to Na2CO3 and NaHCO3. The precipitated alkali flowed out of the reactor with water when the temperature in the reactor decreased to near the critical temperature because of the increasing solubility. Most of the sodium fed into the system (81.07%) was recovered in this process. [Copyright &y& Elsevier]

Abstract: A novel receiver/reactor driven by concentrating solar energy for hydrogen production by supercritical water gasification (SCWG) of biomass was designed, constructed and tested. Model compound (glucose) and real biomass (corncob) were successfully gasified under SCW conditions to generate hydrogen-rich fuel gas in the apparatus. It is found that the receiver/reactor temperature increased with the increment of the direct normal solar irradiation (DNI). Effects of the DNI, the flow rates and concentration of the feedstocks as well as alkali catalysts addition were investigated. The results showed that DNI and flow rates of reactants have prominent effects on the temperature of reactor wall and gasification results. Higher DNI and lower feed concentrations favor the biomass gasification for hydrogen production. The encouraging results indicate a promising approach for hydrogen production with biomass gasification in supercritical water using concentrated solar energy. [Copyright &y& Elsevier]

Abstract: In this work, gasification of sewage sludge in supercritical water was investigated in a fluidized bed reactor. Effect of operating parameters such as temperature, concentration of the feedstock, alkali catalysts and catalyst loading on gaseous products and carbon distribution were systematically studied. The results showed that the increase of temperature and the decrease of feedstock concentration were both favorable for gasification, and the addition of catalyst enhanced the formation of hydrogen better. The K2CO3 catalyst could better enhance gasification efficiency and the catalytic activity of different catalysts for hydrogen production was in the following order: KOH > K2CO3 > NaOH > Na2CO3. The maximum molar fraction and yield of hydrogen reached to 55.96% and 15.49 mol/kg respectively with KOH at 540 °C. Most carbon in feedstock existed in gaseous and liquid products, and alkali catalysts mainly promoted the water-gas shift reaction rather than steam reforming. [Copyright &y& Elsevier]

Abstract: The gasification of sewage sludge in near and super-critical water was investigated in a batch reactor. Results showed that the formation of gaseous products could be intensively affected by temperature. In order to understand the effect of temperature on the development of reaction process and the formation of gaseous products better, the detailed characteristics of solid and liquid products were analyzed by SEM, N2 adsorption–desorption technique, FTIR, TOC, Ammonia–nitrogen analysis and SPE-GC/MS. The changes in the yield distribution of products and the characteristics of solid and liquid products indicated that organic matters in sewage sludge were almost completely dissolved and hydrolyzed in water at 425 °C. The dissolution and hydrolysis products were gasified by reforming and other reactions. The polymerization and dehydrogenation also occurred in dissolution and hydrolysis products, and the Diels–Alder reaction mechanism could be used to explain the phenomenon. [Copyright &y& Elsevier]

Abstract: In this work, glycerol was used for hydrogen production by supercritical water gasification. Experiments were conducted in a continuous flow tubular reactor at 445∼600 °C, 25 MPa, with a short residence time of 3.9∼9.0 s. The effects of reaction temperature, residence time, glycerol concentration and alkali catalysts on gasification were systematically studied. The results showed that the gasification efficiency increased sharply with increasing temperature above 487 °C. A short residence time of 7.0 s was enough for 10 wt% glycerol gasification at 567 °C. With the increase of glycerol concentration from 10 to 50 wt%, the gasification efficiency decreased from 88% to 71% at 567 °C. The alkali catalysts greatly enhanced water-gas shift reaction and the hydrogen yield in relation to catalysts was in the following order: NaOH > Na2CO3>KOH > K2CO3. The hydrogen yield of 4.93 mol/mol was achieved at 526 °C with 0.1 wt% NaOH. No char or tar was observed in all experiments. The apparent activation energy and apparent pre-exponential factor for glycerol carbon gasification were obtained by assuming pseudo first-order kinetics. [Copyright &y& Elsevier]

Abstract: Supercritical water gasification (SCWG) of wet biomass is a very promising technology for hydrogen energy and the utilization of biomass resources. Ni-based catalysts are effective in catalyzing SCWG of original biomass and organic compounds for hydrogen production. In this paper, hydrogen production by SCWG of glucose over alumina-supported nickel catalysts modified with Cu, Co and Sn was studied. The bimetallic Ni–M (M = Cu, Co and Sn) catalysts were prepared by a co-impregnation method and tested in an autoclave reactor at 673 K with a feedstock concentration of 9.09 wt.%. XRD, XRF, N2 adsorption/desorption, SEM and TGA were adopted to investigate the changes of chemical properties between Ni and Ni–M catalysts and the deactivation mechanism of catalysts. According to the experimental results, the hydrogen yield followed this order: Ni–Cu/γAl2O3 > Ni/γAl2O3 > Ni–Co/γAl2O3 > Ni–Sn/γAl2O3. The results show that Cu could improve the catalytic activity of Ni catalyst in reforming reaction of methane to produce hydrogen in SCWG. In addition, Cu can mitigate the sintering of alumina detected by SEM. Co was found to be an excellent promoter of Ni-based catalyst in relation to hydrogen selectivity. [Copyright &y& Elsevier]

Abstract: Hydrogen production by supercritical water gasification (SCWG) is a promising technology for wet biomass utilization. Ni catalyst can realize the high gasification efficiency of biomass near the critical temperature of water. In this paper, Ni/γAl2O3 and Ni/CeO2-γAl2O3 catalysts were prepared by an impregnation method. The catalyst performance for glucose gasification in supercritical water was tested in autoclave reactor. All experiments were carried out in the autoclave at 673 K, 24.5 MPa, and the concentration of glucose was 9.09 wt.%. The catalysts before and after reaction were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), BET specific surface area measurements, X-ray fluorescence spectrum (XRF) and Thermo-gravimetric analyses (TGA) in order to investigate on the chemical property and catalytic mechanism. The experimental results showed that hydrogen yield and hydrogen selectivity increased sharply with addition of Ni/γAl2O3 and Ni/CeO2-γAl2O3 catalysts. The catalytic activity and H2 selectivity of Ni/CeO2-γAl2O3 was higher than that of Ni/γ-Al2O3 catalyst. The results revealed that carbon deposition and coking led to the deactivation of the catalysts. Ce in the Ni/CeO2-γAl2O3 catalyst had a certain role in the inhibition of carbon deposition and coking. [Copyright &y& Elsevier]

The present study aimed at systematically investigating the endophytic communities of dominant plants in the karst ecosystem. Soil and plant materials were collected and after sequencing of the 16 s RNA, the diversity and abundance of the endophytic community structures in leaves were examined. Our results showed that abundant and diverse endogenous bacteria were associated with the leaves of common dominant plants living in the karst ecological environment. Notably, common traits and significant differences in the endophytic community structures were recorded among different plant species with different leaf grown in soils with different calcium contents. These observations implied that plants may adopt different strategies to adapt to the karst ecological environment. In addition, the endophytic bacteria associated with the leaves may be involved in different physiological strategies used by the plants to adapt to the karst ecological environment. These findings provide new avenues for developing microbial agents that could be suitable for the karst ecological environment and will provide sustainable solutions for improving the ability of plants to adapt to karst special adversities, and thus for karst geomorphological environmental protection and agricultural development. [ABSTRACT FROM AUTHOR]

The petal blight disease of alpine Rhododendron severely impacts the ornamental and economic values of Rhododendron. Plant secondary metabolites play a crucial role in resisting pathogenic fungi, yet research on metabolites in alpine Rhododendron petals that confer resistance to pathogenic fungi is limited. In the present study, the secondary metabolites in Rhododendron delavayi , R. agastum , and R. irroratum petals with anti-pathogenic activity were screened through disease index analysis, metabolomic detection, the mycelial growth rate, and metabolite spraying experiments. Disease index analysis revealed that R. delavayi petals exhibited the strongest disease resistance, while R. agastum showed the weakest, both under natural and experimental conditions. UHPLC-QTOF-MS/MS analysis identified 355 and 274 putative metabolites in positive and negative ion modes, respectively. The further antifungal analysis of differentially accumulated baicalein, diosmetin, and naringenin showed their half-inhibitory concentrations (IC50) against Neopestalotiopsis clavispora to be 5000 mg/L, 5000 mg/L, and 1000 mg/L, respectively. Spraying exogenous baicalein, diosmetin, and naringenin significantly alleviated petal blight disease caused by N. clavispora infection in alpine Rhododendron petals, with the inhibition rates exceeding 64%. This study suggests that the screened baicalein, diosmetin, and naringenin, particularly naringenin, can be recommended as inhibitory agents for preventing and controlling petal blight disease in alpine Rhododendron.

Phytophagous insects rely on plant volatiles to select and locate hosts for feeding or reproduction and their olfactory system is essential for detecting plant volatiles. The stem-boring pest, Nassophasis sp. damages Dendrobium and causes economic losses. Currently, there are no effective methods for its control. However, understanding the morphological and molecular basis of its olfactory system may identify new pathways for their management and control. In this study, we observed the stemborer's antennal sensilla using scanning electron microscopy, and transcriptome sequencing was undertaken to annotate and analyze its chemosensory genes. Results showed that the antennal morphology is similar between males and females, with five types of antennal sensilla observed: sensilla chaetica (SC), sensilla trichodea (ST), sensilla brush (SB), sensilla basiconica (SBA) and sensilla gemmiformium (SG). Sexual dimorphism was not observed in sensilla type, but in the length of SBA and SG. A total of 70 olfactory-related genes were annotated, including 16 odorant binding proteins (OBP), 5 chemosensory proteins (CSPs), 26 olfactory receptors (ORs), 9 gustatory receptors (GRs), 10 ionotropic receptors (IRs), and 4 sensory neuron membrane proteins (SNMPs). Most genes were highly expressed and 14 of these genes were only expressed in the head, and 7 genes in the abdomen. This study provides a theoretical basis for the olfactory perception of Nassophasis sp. and a scientific basis for developing new pest control strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Previous studies have indicated that amide proton transfer-weighted imaging (APTWI) could be utilized for differentiating benign and malignant tumors. The APTWI technology has increasingly being applied to breast tumor research in recent years. However, according to the latest literature retrieval, no relevant previous studies compared the value of APTWI and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) in distinguishing benign lesions from malignant lesions. In the present study, the application of APTWI and DCE for differentiating the benign and malignant breast lesions was investigated., Patients and Methods: APTWI was performed on 40 patients (42 lesions) who were enrolled in this prospective study. The lesions were split into two groups, one with malignant breast lesions (n = 28) and the other with benign breast lesions (n = 14), based on the results of the histology. The measured image characteristics (APT value, apparent diffusion coefficient [ADC] value, and time-of-intensity-curve [TIC] type) were compared between the two groups, and the ROC curve was used to quantify the diagnostic performance on the basis of these factors. The correlation between the APT values and the estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER-2), and Ki-67 expression levels and histological grades was examined using Spearman's correlation coefficient., Results: The measured APT and ADC values showed a strong inter-observer agreement according to the intraclass correlation coefficients (0.954 and 0.825). Compared to benign lesions, malignant lesions had significantly higher APT values (3.18 ± 1.07 and 2.01 ± 0.51, p < 0.001). Based on APTWI, DCE, diffusion-weighted imaging (DWI), and ADC + APTWI, ADC + DCE, and DCE + APTWI, the area-under-the-curve values were 0.915, 0.815, 0.878, 0.921, 0.916, and 0.936, respectively., Conclusions: APTWI is a potentially promising method in differentiating benign and malignant breast lesions, and may it become a great substitute for DCE examination in the future., (© 2023 Lulu Zhuang et al., published by Sciendo.)

Root microbiota have a significant effect on plant health. However, the role of root microbiota in the resistance of Rhododendron against root rot is not known. In this study, we employed amplicon 16S and ITS sequencing to investigate the bacterial and fungal communities associated with four distinct niches (bulk soil, rhizosphere, rhizoplane, and endosphere) of both healthy and diseased Rhododendron plants in the Baili Rhododendron nature reserve in China. The amplicon data analysis identified 182 bacterial genera and 141 fungal genera that were impacted by root rot across all niches. Specifically, the rhizoplane appeared to exert a selective gating effect, resulting in a reduction in the complexity of bacterial communities, but not fungal communities, in wild Rhododendron delavayi Franch roots. Nevertheless, the stress induced by root rot led to alterations in the root microbiota and compromised the gating function of the rhizoplane, thereby significantly increasing the complexity of the bacterial community within the plant root. In the root tissue following root rot outbreak, the relative abundance of the pathogenic species Pezicula brunnea and Diaporthe helianthi was enriched by as much as 6.13% and 1.71%, respectively. These findings provide novel insights into the contribution of enrichment of root-associated microbiota to wild plant hosts under the disease stress of root rot. The root rot-causing pathogenic fungi may interact with beneficial bacteria and induce plants to send out "cry for help" signals, which may encourage the specific assembly of microbiota. In the Rhododendron delavayi Franch root microbiota, we found 23 potentially beneficial microbes. Notably, certain beneficial bacteria, such as Sporolactobacillus and Stenotrophomonas , were found to accumulate in the rhizoplane and endosphere under root rot disease stress. Overall, our results lend support to our hypothesis that Rhododendron recruits protective microbes as a strategy to suppress root rot outbreaks. Future endeavors in isolating beneficial microbes capable of mitigating root rot have the potential to enhance plant resilience against root diseases., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Tang, Xiao, Xu, Tang, Zhang and Yi.)