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The drastic effects associated with climate changes, mainly induced by the increasing carbon emissions, challenge our modern society and mandate immediate solutions. This requires in the first place, accelerating the introduction of green alternatives for the standing carbon-based energy technologies, and simultaneously increasing the contribution of the carbon-free renewables to our energy sector. Among a few catalytic processes, the methanation of carbon oxides is currently envisaged as a cornerstone in the renewable energy concepts. On one hand, the methanation of CO is intensively studied for ultra-purification of reforming-generated hydrogen feed gases used in the low-temperature hydrogen fuel cells and in the production of ammonia. This involves the selective methanation of CO in CO 2 -rich H 2 fuels to lower CO concentration from about 5000 ppm down to <5 ppm. The other major application involves the solo or the total methanation of CO and CO 2. This involves the conversion of syngas or the methanation of air-captured CO 2 using green hydrogen produced from renewable energies (power-to-gas). These aspects revive the importance of Sabatier reactions and presents them as an essential part of the cycle of renewable-energy applications. In this review, we will focus on the recent advancements of the methanation of CO and CO 2 on oxide supported Ni and Ru catalysts in the frame of their use in the abovementioned applications. After an overview of different catalytic processes related to hydrogen production, we will basically concentrate on the structure-reactivity relationships of CO and CO 2 methanation in different applications, highlighting limitations and advantages of different catalytic systems. Basically, we will map out the interplay of different electronic and structural features and correlate them to the catalytic performance for CO and CO 2 methanation. This includes the discussion of metal particle size effect, nature of the support, and the effect of reaction gas atmospheres. Clarifying the interplay of these parameters will help us to further understand the metal-support interaction (MSI) based on structural (SMSIs) and electronic (EMSIs) aspects which is essential for steering the catalytic performance of these catalysts for a specific reaction pathway. [Display omitted] • Sabatier reactions play decisive role in renewable energy applications. • Methanation performance of supported catalysts strongly dependent on application. • Decisive role of metal-particle size for both CO and CO 2 methanation. • MSI can be optimized to fine-tune methanation activity and selectivity. [ABSTRACT FROM AUTHOR]

The separator is used to isolate the cathode and anode material, playing an important role in the safety of battery, which prevents internal short circuit of battery and provides lithium ions free flow channels. In this paper, based on the commercial ceramic-coated polyethylene (PE) separator (CPES), low-melting point PE microspheres were mixed in ceramic-coating to form the functionalized PE separator (FPES) for improving the safety tolerance of large scale lithium-ion batteries (LIBs). Compared to the CPES shutdown temperature of ~135 °C, the shutdown temperature of FPES significantly decreased to ~110 °C. Compared with 27 Ah pouch battery assembled by CPES, the FPES can effectively improve the tolerance of overcharge and internal short circuit without sacrificing the electrochemical performance. In addition, a novel internal short circuit of FPES protection mechanism model was proposed. Molten PE microspheres of FPES would flow along the edge of broken hole, reducing the contact probability between the cathode and anode, and ultimately increasing the resistance of internal short circuit by 41% compared to CPES. Therefore, the obtained results provide important implications for the development of safer separator and LIBs. [ABSTRACT FROM AUTHOR]

Highlights • Muscovy duck reovirus (MDRV) causes infection and economic losses in the Muscovy duck industry. • CA strain was developed as a live attenuated vaccine candidate after serial passages of MDRV virulent strain MW9710. • CA strain is highly immunogenic to protect the ducks from MDRV infection. • A single dose of CA vaccine is sufficient to protect the birds from MDRV infection. • Safety and protective efficacy characteristics were considered for the development of a live attenuated vaccine against MDRV. Abstract The Muscovy duck reovirus (MDRV) is a highly pathogenic virus that causes substantial economic losses in the Muscovy duck industry. While MDRV poses a significant threat to Muscovy ducklings, no vaccine candidates are available to date to alleviate MDRV infection throughout the world. The present study presents efforts toward establishing an attenuated vaccine for MDRV. For this purpose, a live attenuated vaccine strain named CA was obtained via alternate propagation of the MDRV isolate MW9710 in both Muscovy duck embryo fibroblasts (MDEFs) and chicken embryo fibroblasts (CEFs) for 90 passages. The CA strain achieved an adaptive growth capacity in CEFs with a viral titer that ranged between 105.0–105.5 TCID 50 /100 μL and lost its pathogenicity in 1-day-old Muscovy ducklings. Compared to the parent strain MW9710, the CA strain has 42 scattered amino acid substitutions, most of which are located in the λB, λC, μB, σB, and σC protein. The CA strain maintained its attenuation and showed no gene mutation or virulence reversion after back propagation into 1-day-old ducklings for five rounds. The minimum protective dose was calculated to be 300 TCID 50 of the CA strain. Furthermore, a single dose of CA vaccine protected immunized ducklings against lethal challenge by the virulent MDRV strain MW9710 and significantly decreased viral loads. In summary, the CA strain exhibited striking genetic stability, excellent safety, and effective immunogenicity. This CA strain of MDRV is a promising vaccine candidate for the prevention and control of MDRV infection. [ABSTRACT FROM AUTHOR]

Short beak and dwarfism syndrome virus (SBDSV) is a newly emerging distinct duck-origin goose parvovirus that belongs to the genus Dependovirus. Our previous studies have found that SBDSV was highly pathogenic to Cherry Valley ducklings and mule ducklings. However, little is known about its pathogenicity to other waterfowls. In the present study, the pathogenicity of SBDSV was evaluated in domesticated waterfowl including Muscovy ducklings, Sheldrake ducklings and domestic goslings. All experimentally infected birds exhibited remarkable growth retardation, anorexia and diarrhea similar to naturally infected birds. Interestingly, atrophic beaks and protruded tongues were not observed in all infection groups. At necropsies, no diagnostic pathological lesions were observed. Viral antigens existed in most organ tissues such as heart, liver, spleen, kidney, pancreas and intestine. All ducks in Muscovy duckling and Sheldrake duckling infected groups and 70% goslings in infected groups were seropositive for goose parvovirus (GPV) antibodies at 21 dpi with the average titers as 2 8.4 , 2 6.9 , 2 4.0 , respectively. Muscovy ducklings were more prominent in viral load and weight loss with a higher GPV antibodies titer than Sheldrake ducklings and goslings. Taken together, SBDSV exhibits a wide range of pathogenicity to main domesticated waterfowl with variable symptoms and cause considerable economic losses in China. [ABSTRACT FROM AUTHOR]

The influence of Si doping of high specific-surface-area Ru/TiO 2 catalysts with similar structural properties on the CO 2 reduction reaction was systematically investigated by kinetic measurements, combined with microscopic and spectroscopic methods for ex situ and in situ / operando catalyst characterization. While for undoped Ru/TiO 2 a high-temperature treatment (350 °C) in reaction atmosphere results in a pronounced change of the selectivity from methanation to CO formation via the reverse water-gas shift (RWGS) reaction, CH 4 formation is stabilized by Si doping of the catalyst support. For doping levels around 8 wt%, almost 100% CH 4 selectivity is maintained. Comprehensive catalyst characterization is employed to identify trends in the physical and chemical properties with increasing Si doping and thus physical reasons responsible for the distinct differences in catalyst performance and stability. This work opens a route for improving the stability and selectivity of Ru/TiO 2 catalysts in the CO 2 hydrogenation reaction, a highly relevant application. [Display omitted] • High-surface-area (SSA) Ru/TiO 2 catalysts are highly active for CO 2 hydrogenation. • High-SSA Ru/TiO 2 catalysts are 100% selective for methane formation. • This high selectivity breaks down after temperature excursions during reaction. • Si doping stabilizes selectivity of high-SSA Ru/TiO 2 catalysts for CO 2 methanation. • Catalyst characterization reveals complex origin of the thermal stabilization. [ABSTRACT FROM AUTHOR]

A facile synthesis of silver nanochains was represented by directly reducing the silver ions adsorbed on the DNA chains. The synthesized silver nanochains consist of spherical nanoparticles (10–20 nm) connected together in line. Then the flexible electrical conductive composites were fabricated for the first time by incorporating Ag nanochains and Ag-coated Cu flakes in polymer matrix. The silver nanochains play important roles of flexible and conductive bridges to construct effective electronic networks among the fillers. The composites filled with small amount of AgNPs shows a much lower volume resistivity of 2.13×10 -4 Ω cm, and the resistance change ( R / R 0 ) was only 3.65 when rolling at 4 mm, while that of controlled sample reached to 8.89. This method provides a new perspective for researchers to further explore other chain-like metal and their applications in flexible electrical conductive materials. [ABSTRACT FROM AUTHOR]

Abstract: The combination of metal nanostructures and pristine graphene with high quality is highly expected for many applications. A method for the large-scale production of metal nanoparticle (NP)/pristine graphene hybrid and its conductive polymer composites is presented, by a combinatorial process of noncovalent functionalization of defect-free pristine-graphene with Poly(amidoamine) (PAMAM) dendrimer and the homogenous attachment of metal NPs on graphene surface. Stable PAMAM functionalized graphene nanofluid is achieved when there is the absence of solvents. The graphene sheets in the hybrid preserve the intrinsic structure and homogenous dispersion. Silver NP (AgNP) decorated graphene hybrid with homogenous dispersion is realized by using PAMAM as stabilizing and also reducing agents through thermal reduction method. The hybrid is used as nanoscale filler to generate epoxy-based conductive composites for electrical interconnects due to the combined effects of the excellent electrical conductivity of high-quality pristine-graphene at low percolation threshold and enhanced contacts between the fillers by low temperature sintering of AgNPs. This method could lead to the large-scale production of graphene-based composites for a wide range of applications. [Copyright &y& Elsevier]

Abstract: 4-Aminobenzoyl-functionalized graphite is produced by the edge-functionalization of pristine graphite with 4-aminobenzoic acid via Friedel–Crafts acylation reaction. The edges of solid functionalized graphite are exfoliated with a high degree. The functionlization predominantly occurs at the edge region of graphite and the structure of pristine graphene in the interior basal planes is retained. The solid functionalized graphite is a promising precursor for the exfoliation into few layer graphene sheets in low boiling point solvents under ultrasonication. The functionalized graphene sheets are employed as nanoscale reinforcement to prepare epoxy-based conductive composite for electrical interconnects. The results show that the electrical conductivity of the composites with addition of 0.6wt% functionalized graphene has an increase of 31.3% and the shear strength of the composites simultaneously improves from 8.7MPa to 15.2MPa. The covalent interactions between graphene and epoxy matrix provided by terminal amino groups can maintain the excellent dispersion of graphene in the matrix, leading to a 3D network. The graphene sheets come in contact with microscale silver fillers, constructing effective electrical bridges between the fillers. The increased flexibility of epoxy network leads to the reinforcement of shear strength. This technique extends the application of graphene in the conductive composites for electrical interconnects. [Copyright &y& Elsevier]

A facile method to prepare low-cost, highly conductive and reliable silver-coated copper (Ag-coated Cu) flakes filled isotropic conductive adhesive (ICAs) by in situ generation and sintering of silver nanoparticles (AgNPs) during the curing process is presented. The silver–triethanolamine complex is derived from the complexing reaction between AgNO3 and triethanolamine in the epoxy matrix. At the curing temperature, AgNPs are in situ generated by the thermal decomposition of silver–triethanolamine complex. The sintering of AgNPs anchored on the surface of Ag-coated Cu flakes could effectively prevent the exposed Cu from oxidizing. Compared with the ICAs without AgNPs which has a resistivity of 9.6×10−4 Ωcm, the ICAs filled with AgNPs shows a much lower volume resistivity of 6.62×10−4 Ωcm. Furthermore, the contact resistance of the ICAs is only 6.7% increase after aging at 85°C and 85% RH for 500h, while the increase in contact resistance of the controlled ICAs reaches to 23%. The facile approach will pave the way towards high performance and low cost ICAs for electronic packaging applications. [ABSTRACT FROM AUTHOR]

Microfibrous structured Ag@SiO 2 -Co 3 O 4 /Al-fiber catalyst, used for catalytic combustion of trace ethylene, is tailored with water-soluble silane coupling agent that has functionally specified multi-groups as bidirectional bridging reactant. Hydrothermally synthesized Co(OH) 2 /Al-fiber nanoarrays can be readily functionalized by amine groups via the silanisation reaction to form Co-O-Si bonds, followed by the assembly of Ag nanoparticles onto this microfibrous-structured substrates by coordination interaction. The as-prepared Ag@SiO 2 -Co 3 O 4 /Al-fiber catalyst uses very low Ag loading of only 0.2 wt% but exhibits high activity/stability at high-throughput operation. Ethylene conversion higher than 99 % was achieved at 200 °C under dry atmosphere, which shows no signs of deactivation with C 2 H 4 conversion retained at ~94 % within 120 h running. Experimental and theoretical studies unanimously revealed that the Ag@SiO 2 -Co 3 O 4 core-shell structures with strong metal-support interaction favor to bind and dissociate intermediate species during C 2 H 4 oxidation, contributing to high activity of C 2 H 4 oxidation. [Display omitted] • Microfibrous-structured Ag@SiO 2 -Co 3 O 4 /Al-fiber catalyst was developed for catalytic combustion of trace ethylene. • The catalyst used very low Ag loading, but exhibited enhanced activity/stability at high-throughput operation. • The catalyst was obtained by using water-soluble silane coupling agent as bidirectional bridging reactant. • Our unique organization strategy endowed catalyst with strong metal-support interaction (SMSI). • SMSI favors to activate and dissociate C 2 H 4 and O 2 , contributing to high C 2 H 4 -oxidation activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Au loading/particle size affects performance of Au/ZnO catalysts for CO 2 reduction. • Selectivity for methanol formation increases with Au particle size. • Partial overgrowth of the Au NPs during reaction. • Formation of O-vacancies during reaction. • r Overgrowth/vacancy formation increases/decreases with Au loading and particle size. Methanol synthesis by CO 2 reduction is an important approach for energy storage. Aiming at a reduction of the catalyst mass in technical applications, we have investigated the influence of increasing Au loading on the performance of Au/ZnO in methanol and CO formation from CO 2 reduction. Using the same type of ZnO support, increased Au loading resulted also in a pronounced increase in Au particle size. The Au-mass-normalized reaction rate for methanol formation and TOF decrease with increasing Au loading/particle size, while the selectivity for methanol formation increases. CO adsorption monitored by in situ FTIR revealed a pronounced decrease of the accessible Au surface area during reaction, independent of the Au loading, pointing to a partial encapsulation of the Au nanoparticles by a partly reduced ZnO x , as described by SMSI effects. Possible reasons responsible for these effects and Au loading/size effects therein are discussed, strategies for future work are outlined. [ABSTRACT FROM AUTHOR]

Abstract: Inter-simple sequence repeat markers (ISSR) were used to estimate genetic diversity within and among 10 populations of Rhodiola chrysanthemifolia along Nianqingtangula Mountains and Brahmaputra, a species endemic to the Qinghai-Tibet Plateau and an endangered medicinal plant. Of the 100 primers screened, 13 produced highly polymorphic DNA fragments. Using these primers, 116 discernible DNA fragments were generated of which 104 (89.7%) were polymorphic, indicating substantial genetic diversity at the species level. Genetic diversity measured by the percentage of polymorphic bands (PPB) at the population level ranged from 21.97% to 48.8%. Analysis of molecular variance (AMOVA) showed that the genetic variation was found mainly among populations (77.3%), but no regional differentiation was discernible. Variance within populations was only 22.7%. The main factor responsible for this high level of differentiation among populations is probably the historical geographical and genetic isolation of populations in a harsh mountainous environment. Concerning the management of R. chrysanthemifolia, the high genetic differentiation of populations indicates the necessity of conserving the maximum possible number of populations. [Copyright &y& Elsevier]

• Si doping modifies activity of high-surface-area Ru/TiO 2 for selective methanation. • CO methanation activity variation with Si content exhibits volcano-type shape. • CO adsorption strength variation with Si content exhibits volcano-type shape. • Highest catalytic activity correlated to the weakest CO adsorption strength. Aiming at a better understanding of the role of electronic / chemical modifications of the support on the performance of high specific surface area Ru/TiO 2 catalysts in the selective CO methanation, we prepared and examined four different Ru/TiO 2 catalysts with similar Ru loading and similar high specific surface area, but with the support doped with different amounts of Si (0–12 wt.% SiO 2). Their activity for methane formation exhibits a volcano-shaped dependence on the SiO 2 content, with a maximum between 4 and 8 wt.%. The CO adsorption properties showed distinct differences, with the weakest CO adsorption strength for the most active catalysts. Based on the results of a variety of different characterization techniques and pyrrole/pyridine adsorption measurements, the higher activity / lower CO adsorption strength cannot be explained by a single property, such as particle size, but must rather be caused by a complex combination of different effects. [ABSTRACT FROM AUTHOR]

Fundamental understandings of surface chemistry and catalysis of solid catalysts are of great importance for the developments of efficient catalysts and corresponding catalytic processes, but have been remaining as a challenge due to the complex nature of heterogeneous catalysis. Model catalysts approach based on catalytic materials with uniform and well-defined surface structures is an effective strategy. Single crystals-based model catalysts have been successfully used for surface chemistry studies of solid catalysts, but encounter the so-called "materials gap" and "pressure gap" when applied for catalysis studies of solid catalysts. Recently catalytic nanocrystals with uniform and well-defined surface structures have emerged as a novel type of model catalysts whose surface chemistry and catalysis can be studied under the same operational reaction condition as working powder catalysts, and they are recognized as a novel type of model catalysts that can bridge the "materials gap" and "pressure gap" between single crystals-based model catalysts and powder catalysts. Herein we review recent progress of surface chemistry and catalysis of important oxide catalysts including CeO 2 , TiO 2 and Cu 2 O acquired by model catalysts from single crystals to nanocrystals with an aim at summarizing the commonalities and discussing the differences among model catalysts with complexities at different levels. Firstly, the complex nature of surface chemistry and catalysis of solid catalysts is briefly introduced. In the following sections, the model catalysts approach is described and surface chemistry and catalysis of CeO 2 , TiO 2 and Cu 2 O single crystal and nanocrystal model catalysts are reviewed. Finally, concluding remarks and future prospects are given on a comprehensive approach of model catalysts from single crystals to nanocrystals for the investigations of surface chemistry and catalysis of powder catalysts approaching the working conditions as closely as possible. Image 1 [ABSTRACT FROM AUTHOR]

• In this work, we applied the particle image velocimetry (PIV) to measure the turbulent flow downstream a split-type mixing vane spacer grid in a 5×5 rod bundle with the aid of matched index of refraction (MIR). • The experimental uncertainty and results were evaluated, and the Reynolds effect on the turbulent flow was also discussed in the paper. • The cross flow measurements show the mixing mechanism of spacer grid with mixing vanes. And the mixing vanes determined the cross flow downstream the spacer grid. Axial and cross flow downstream a split-type mixing vane spacer grid in a 5×5 rod bundle are measured with particle image velocimetry (PIV) at sub-channel Reynolds number (Re sc) of 6600, 13,200, 26,400 and 39,600. The cross flow in the sixteen inner sub-channels are obtained at five elevations, i.e. 3D h , 5D h , 10D h , 15D h and 20D h downstream of the spacer grid. The axial flow measurement is conducted in a plane parallel to the bundle axis. The satisfactory convergence of turbulent statistics is achieved with the sampling number of 2000. The maximum standard uncertainty of statistical quantities normalized by the bulk velocity for all the test conditions is less than 0.6%. The flow characteristics and structures were determined by the mixing vanes located on the upper edge of support grids in rod bundle, and the flow downstream the spacer grid can be divided into the advection zone, the reorganization zone and the dumping zone. And the maximum lateral velocity decreases from 44% of the bulk velocity (W b) at 3D h to 16%W b at 20D h. The mixing vanes generate drastic turbulence flow downstream the spacer grid, and the lateral root mean square (RMS) fluctuating velocity decays in exponential way. The maximum lateral RMS fluctuating velocity decays rapidly from 20%W b at 3D h to 9%W b at 20D h. The maximum lateral Reynolds stress decreases from 0.6% W b 2 at 3D h to 0.3% W b 2 at 20D h. The normalized mean velocity and turbulent statistics show similarity for the Reynolds above 13,200, while the low Reynolds number effect at Re = 6600 is observed for the axial mean velocity and axial RMS fluctuating velocity. [ABSTRACT FROM AUTHOR]

Highlights • Optimizations of PIV measurement for cross flow in rod bundle were conducted. • Several important sources of uncertainty were identified and quantified with caution. • High-fidelity experimental data were captured and discussed. Abstract In order to achieve high-fidelity PIV measurement for cross flow in rod bundles, the measurement approach with the two-dimensional (2D) PIV has been optimized systematically and the systematic and random errors are analyzed. The optimizations, covering the design of test section, the setting of optical system, the PIV parameter configuration and the PIV correlation algorithm, were established based on massive sensitivity analysis. Utilizing the optimized PIV configuration, cross flow measurements were conducted in a 5 × 5 rod bundle with the rods 9.5 mm in diameter and the rod pitch of 12.6 mm, which is the typical configuration of fuel assembly in pressurized water reactors (PWRs). The FEP tubes filled with deionized water are employed as the matched index of refraction (MIR) rods to realize uniform illumination across the rod bundle. On each investigated cross section the cross flow was measured in the 16 inner subchannels. In order to maximize the magnification factor, four subchannels are measured in a single test run. Several substantial error sources were identified and accounted for in the error and uncertainty analysis. The systematic error consists mainly of the perspective error and displacement variation error, which were quantified and used to correct the measured results. The uncertainty of RMS velocity is the combination of random error and error due to limited sampling number, while the uncertainty of mean velocity equals to the error resulted from limited sampling number assuming that the systematic error is perfectly compensated. In the experiment the relative standard uncertainty of RMS velocity (to the bulk velocity) is within 0.6%, and the relative standard uncertainty of mean velocity (to the bulk velocity) is less than 0.4%. The measurements were carried out with the subchannel Reynolds number (Re) of 39600 at five cross sections, i.e. 3D h , 5D h , 10D h , 15D h and 20D h downstream of a spacer grid. The experimental results showed the detailed cross flow features, including the evolution of vortices, in the rod bundle. The measured lateral flow was substantially dominated by the mixing vanes. Drastic turbulence generation by mixing vanes was observed downstream of a spacer grid. The generated turbulence decayed rapidly within 10D h downstream of the spacer grid and then damped gradually. [ABSTRACT FROM AUTHOR]

• Population genetic analyses and ecological niche data did not support Aconitum pendulum and A. flavum as two separate species. • Gene flow and genetic drift may weaken the genetic difference and its correlation with geographical distance. • The bottleneck effect was detected among populations of A. pendulum and A. flavum during the Last glacial maximum. • Human activity, such as overexploitation causing habitat fragmentation, might be one of the factors that threat to the survival of A. pendulum and A. flavum in the current period. As species are fundamental units of evolutionary biology research, accurate species delimitation plays a crucial role in current biodiversity management. The Qinghai-Tibet Plateau (QTP) comprises one of the global biodiversity hotspots, and plant speciation and its evolutionary history in this region still need much research. Aconitum pendulum and A. flavum (Ranuculaceae) are mainly distributed in the QTP and its adjacent regions. The two species have extremely similar morphological characteristics, and their evolutionary relationship is still controversial. In this study, we collected 244 individuals in 14 populations from the main distribution areas of the two species. Genome-wide single-nucleotide polymorphisms (SNPs) from genotyping-by-sequencing (GBS) of A. pendulum and A. flavum were obtained to decipher the taxonomic delimitation and explore the evolutionary history. We performed neighbor-joining (NJ), PCA, structure, and niche overlap analyses. None of them support that A. pendulum and A. flavum can be considered as two separate species. In addition, the genetic difference between species is less than that among populations. We propose merging the two species into one. We also found that the genetic difference between the two species was not associated with morphological species or geographic distance. Gene flow and genetic drift may play a crucial role in weakening the correlation between genetic distance and geographical distance. A bottleneck effect occurred in the two species during the last glacial maximum. Based on the Maxent and Stairway Plot results, we inferred that A. pendulum and A. flavum still had large survival ranges during the LGM, similar to other cold-tolerant species. Furthermore, human activity, such as overexploitation causing habitat fragmentation, might be one of the factors that threat to the survival of A. pendulum and A. flavum in the current period. [ABSTRACT FROM AUTHOR]

A multiplex polymerase chain reaction (PCR) method was developed to detect and distinguish goose parvovirus (GPV), waterfowl reovirus (WRV), and goose astrovirus (GAstV). Three pairs of primers were designed based on conserved regions in the genomic sequences of these enteric viruses and were used to specifically amplify targeted fragments of 493 bp from the viral protein 3 (VP3) gene of GPV, 300 bp from the sigma A-encoding gene of WRV, and 156 bp from the capsid protein-encoding gene of GAstV. The results showed that the primers can specifically amplify target fragments, without any cross-amplification with other viruses, indicating that the method had good specificity. A sensitivity test showed that the detection limit of the multiplex PCR method was 1 × 103 viral copies. A total of 102 field samples from Muscovy ducks with clinically suspected diseases were evaluated using the newly developed multiplex PCR method. The ratio of positive samples to total samples for GPV, WRV, and GAstV was 73.53% (75/102) for multiplex PCR and was 73.53% (75/102) for routine PCR. Seventy-five positive samples were detected by both methods, for a coincidence ratio of 100%. This multiplex PCR method can simultaneously detect GPV, WRV, and GAstV, which are associated with viral enteritis, thereby providing a specific, sensitive, efficient, and accurate new tool for clinical diagnosis and laboratory epidemiological investigations. • A multiplex PCR assay was developed for simultaneous detection for GPV, WRV, and GAstV in Muscovy duck flocks, with good specificity, good accuracy, and high sensitivity. • The multiplex PCR was able to detect at least 1 × 103 viral copies of GPV, WRV, and GAstV. • The multiplex PCR developed is a useful tool for clinical diagnosis of single virus and/or mixed infections in Muscovy duck. [ABSTRACT FROM AUTHOR]

Abstract: To clarify the relationship between two genera, Draba and the narrow genus Coelonema, endemic to the QilianMountains of the northeastern Qinghai-Tibet Plateau, phylogenetic analyses were conducted using nuclear ribosomal DNA ITS, and the chloroplast DNA trnL, from Coelonema draboides and 30 species of Draba representing eight sections, including 25 species of Chinese Draba, seven of which were endemic to the study region. The results unambiguously support several previously published proposals to unite Coelonema with Draba and accommodate C. draboides in the latter genus on the basis of morphological re-examination. Our molecular data presented here also provide evidence that these two genera should be combined as a monophyletic group with high support. In addition, it is estimated that Draba may have originated about 1.36–2.71 Mya, with C. draboides diverging from Draba about 0.15–0.31 Mya, based on the molecular calibration of ITS datasets. The assumed speciation and rapid expansion of these two genera is likely to have occurred in the eastern edge of the QilianMountains area according to molecular phylogeny and estimated divergence times, which correspond well with the known geological and paleobotanical histories of the Qinghai-Tibet Plateau. [ABSTRACT FROM AUTHOR]

Sinopodophyllum hexandrum is an important traditional Tibetan medicinal plant with great development potential in pharmaceutical industry because of the presence of major bioactive lignans such as podophyllotoxin (PT) that are widely used in combination therapy of cancer. In this study, a green and efficient method for the extraction of PT from S. hexandrum was established by optimized subcritical water extraction (SWE) combined with macroporous resin enrichment. Response surface methodology was introduced for SWE optimization to obtain the maximum yield of PT. The maximum extraction efficiency was achieved under the following conditions: extraction pressure 4 MPa, extraction solvent to feed ratio 18 mL/g, extraction temperature 180 °C, and SW flow rate 2.5 mL/min. Subsequently, an efficient macroporous resin enrichment method was developed to further purify PT in the crude extract obtained from SWE. D101 resin was selected as a proper adsorbent owing to its adsorption and desorption properties, whereas its adsorption process was found to be consistent with a pseudo-second-order model. The optimized loading amount was 3 BV of extract solution, and the desorption conditions were as follows: First, the product was eluted with deionized water until no sugar was detected in the effluent, followed by 6 BV of 20% aqueous ethanol elution and then by 15 BV of 60% aqueous ethanol elution. After the treatment with D101 resin, the concentration of PT increased from 8.3% in the crude extract to 61.5% in the final product. Moreover, the recovery yield of PT extracted with SW combined with D101 resin enrichment was 74.6%. The results show that SWE combined with macroporous resin enrichment is a green, effective, and low-cost technique for the extraction of PT from S. hexandrum. [ABSTRACT FROM AUTHOR]

Plants growing in different climate retain the general direction of the biosynthesis of the volatile organic compound (VOC). The aim of this study was to investigate the VOC composition in Artemisia vulgaris L. growing on the Qinghai–Tibet Plateau. The VOCs were isolated by hydrodistillation or by headspace extraction, and their composition was analyzed by gas chromatography–mass spectrometry (GC–MS). There were 96 VOCs identified in the samples, accounting for 91–97% of the total. Monoterpenes (80.33%) were the main components of VOCs released by headspace extraction. The major components of essential oil obtained by hydrodistillation were monoterpenes (44.49%) and sesquiterpenes (29.98%). The monoterpenes 1,8-cineole, camphor, and α- and β- thujones were the main VOCs detected after both hydrodistillation and headspace extraction. Sesquiterpenes ( cis -davanone, germacrene D) also accounted for a significant proportion of compounds in the essential oil. A principal component analysis (PCA) based on the types of components of essential oils of A. vulgaris collected from different countries showed that the moisture conditions at the collection site was the main factor explaining variations in VOC composition, and were located between “European” and “Siberian” chemotype, which indicated that the essential oil profile does not fully reflect zonal climatic features. [ABSTRACT FROM AUTHOR]

Gentiana straminea is a popular Tibetan medicine that has been used for thousands of years in China to treat various diseases and conditions. Although it has multiple pharmaceutical purposes and important economic plant resource in China, transcriptome and molecular base still known limited. In flowering season, samples were collected from different tissues, using the NGS Illumina. Solexa platform, about 58.85 million sequencing reads were generated and assembled de novo, yielding 78,764 high quality unigenes with an average length of 1090 bp. Gene Ontology (GO), KEGG pathway mapping showed that 49,033 of these were identified as putative homologs of annotated sequences in the protein databases. Among them, candidate genes associated with iridoid, flavonoid and anthocyanin were identified. Further the key enzymes involved to iridoid and flavonoid synthesis pathway were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) on different tissues, the flower and root had the higher expression than leaves. In addition, 7591 SSR markers were identified from the unigenes of the G . straminea transcriptome. The foundation of G . straminea provided the important resource for facilitating to study molecular and functional genomics of it and related this species on the Qinghai–Tibet Plateau. [ABSTRACT FROM AUTHOR]

Transcriptome sequencing is a powerful tool for the assessment of gene expression and the identification and characterization of molecular markers in non-model organisms. Rhodiola algida L. (Crassulaceae), endemic to the Qinghai-Tibetan Plateau, has long been used in traditional Chinese medicine to prevent altitude sickness and eliminate fatigue. Illumina-based high-throughput transcriptome sequencing of aboveground and underground tissues of R. algida respectively yielded 5.40 million and 5.18 million clean reads. A total of 82,664 unigenes averaging 577 bp in length were generated from the aboveground clean reads, with 86,237 unigenes of 502-bp mean length obtained from the underground tissues. Of 55,028 unigenes compared with sequences in UniProt databases, 20,413 unigenes had significant similarities with existing sequences in NR, NT, Swiss-Prot, GO, KEGG, and COG databases. Single nucleotide polymorphism (SNP) analysis identified 237,294 SNPs from 154,636 contigs of aboveground tissues and 197,540 SNPs from 144,963 underground-derived contigs. The information uncovered in this study should serve as a valuable resource for the characterization of important traits related to secondary metabolite formation and for the identification of associated molecular mechanisms. [ABSTRACT FROM AUTHOR]

The Qinghai-Tibetan plateau (QTP) uplift had a decisive effect on climatic and eco-environmental evolution in East Asia during the Quaternary. In the current study phylogeographic structure and diversification history of Spiraea alpina across the QTP were investigated for the first time based on nuclear internal transcribed spacer. The nuclear internal transcribed spacers ( ITS 1a –ITS 4 ) were generated for a total of 284 individuals distributed within 31 natural populations. A clear phylogeographic structure was found for S. alpina . The results showed that this species colonized in three different glacial refugia during the Quaternary extensive glaciation and expanded during the Interglacial period. Analysis of molecular variance (AMOVA) showed 74.13% genetic diversity among populations and 25.87% genetic variation within populations with distinct phylogeographic structure ( F ST = 0.741*). The estimated divergence time revealed that the main lineages of S. alpina diversified during the Quaternary 1.2–0.6 million years ago. The study concluded that severe climatic oscillations during Quaternary and the uplift of QTP had a profound effect on intraspecific divergence of S. alpina . [ABSTRACT FROM AUTHOR]

Gentiana straminea Maxim. is a well-known Tibetan traditional herb, which has been used to treat rheumatic arthritis, iceteric hepatitis, and other diseases for thousands years. However, there is still lack of comprehensive active constituents profiling of this species throughout the Qinghai-Tibet Plateau (QTP). This study was designed to provide a comprehensive quality map of G.straminea germplasm based on twelve active constituents (loganic acid, gentiopicroside, swertiamarin, sweroside, 6-O-β-D-glucosylgentiopicroside, oleanic acid, morroniside, trilobatin, isoorientin, isovite, Shanzhisidemethylester and quercetin) on the QTP. G.straminea root samples collected throughout QTP in the flowering period were analyzed by the LC-MS/MS. Statistics analysis methods PCA, clustering and ecological regions analysis for G.straminea constituents differentiation was demonstrated. The active constituents varied greatly across the QTP; the majority of constituents were secoiridoid derivatives, with gentiopicroside being the most abundant compound. Most constituents were significantly affected by the latitudes and altitudes other than longitudes. PCA and hierarchical clustering analysis showed that all samples could be separated into six distinct groups, and 15 populations showed the highest constituent abundances. Further, geographical region analysis showed that the highest quality populations mainly located near the source region of Yellow River, especially in the Qinghai and Sichuan areas. Additionally, correlation analysis showed that there were relationships among genetiopicroside, loganic acid, and other compounds, which might be related to the enzymatic pathways involved in the metabolism of these constituents. Conclusion : LC-MS/MS method allowed separation of quality profiling of G.straminea on the QTP, 15 populations showed the highest constituent abundances. In six geographical groups, the highest quality populations mainly located near the source region of Yellow River, especially in the Qinghai and Sichuan areas, which may be due to the climate caused by the westerlies and Indian Ocean monsoons in the QTP. [ABSTRACT FROM AUTHOR]

• A universal extraction was developed to extract arsenic species in various seafood with an efficiency > 95%. • The arsenic species keep no altering during extraction and extract can be directly used for IC-ICP-MS detection. • A universal IC-ICP-MS method was developed for the detection of each arsenic species in various seafood. • The developed methods have broad applicability and high sensitivity. The speciation analysis of arsenic in seafood is of great significance for objectively and scientifically assessing arsenic health risks in seafood. In general, different types of seafood contain a variety of different arsenic species and have quite different matrix. Thus, the detection of arsenic species in different types of seafood required different extracting and analytical methods. In this study, a universal microwave-assisted extraction was developed to extract each arsenic species including As(V), As(III), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), arsenobetaine (AsB), arsenosugars and so on in various seafood with a extraction efficiency > 95% and without altering their original species, and a universal cation exchange IC-ICP-MS (ion chromatography-inductively coupled plasma mass spectrometry) method was developed for the detection of arsenic species in various seafood (seaweed, fish, shellfish and shrimp) with a method detection limit of 8.0 ng As/g dried seafood–12.0 ng As/g dried seafood. Especially, the extract of seafood obtained with our microwave-assisted extraction can be directly used for the following IC-ICP-MS detection without any additional pretreatment. By using the extraction method and IC-ICP-MS method, we have successfully detected each arsenic species including As(V), As(III), MMA, DMA, AsB, arsenosugars and so on in seaweed, fish, shellfish and shrimp samples with a recovery of 92%–104% and a relative standard deviation (RSD, n = 5) < 5%. The developed microwave-assisted extraction method and IC-ICP-MS detection method is simple, has broad applicability, high efficiency, excellent accuracy and strong resistibility to the complicated matrix, which promising a reliable approach for objectively and scientifically assessing arsenic health risks in various seafood to ensure the consumption safety of seafood. [ABSTRACT FROM AUTHOR]

• A TaqMan-MGB probe-based one-step real-time RT-PCR assay for the rapid detection of H146-like GCV was developed. • The assay in this study was simple and highly specific. • This approach will help to provide knowledge on epidemiological study focused on H146-like GCV infection. H146-like goose-origin calicivirus (H146-like GCV) is a novel Caliciviridae family member in the Sanovirus genus that was associated with gosling growth retardation syndrome growth retardation syndrome complicated by visceral urate deposition. However, there is no accurate and high throughput real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) available for the rapid and highly sensitive identification of H146-like GCV. In this study, a pair of specific primers and a TaqMan minor groove binder (MGB) probe were designed based on a conserved region in the nonstructural (NS) gene sequence. The TaqMan-MGB probe-based one-step qRT-PCR assay was capable of detecting quite low number of targeting nucleic acid as low as 5.07 copies/μL and had excellent intra-assay and inter-assay repeatability with the coefficient of variation (CV) value from 0.558% to 1.293%. The assay was highly specific for H146-like GCV, without cross-reactions with other non-targeted goose-origin viruses, and 62 suspicious tissue samples infected with H146-like GCV from different regions of Fujian Province were used in this study to verify the feasibility and effectiveness of this assay in clinical diagnosis. The results indicated that our assay for the diagnosis and quantification of H146-like GCV was highly sensitive and specific, and should provide a reliable real-time tool for epidemiological and pathogenetic study of H146-like GCV infection, enabling researchers to better understand the epidemiology and clinical presentation of this disease. [ABSTRACT FROM AUTHOR]

• Morphology-dependent CeO 2 catalysis is established in C 2 H 2 semihydrogenation reaction. • Catalytic performance follows an order of r-CeO 2 -500 ≫ c-CeO 2 > r-CeO 2 -700. • Ability to chemisorb C 2 H 2 (a) follows an order of r-CeO 2 -500 ≫ c-CeO 2 ≈ r-CeO 2 -700. • Ability to dissociate H 2 follows an order of c-CeO 2 > r-CeO 2 -500 ≫ r-CeO 2 -700. We herein investigated the catalytic performances and reaction mechanisms of CeO 2 cubes (denoted as c-CeO 2), CeO 2 rods calcined at 500 °C (denoted as r-CeO 2 -500), and CeO 2 rods calcined at 700 °C (denoted as r-CeO 2 -700) in the acetylene semihydrogenation reaction. r-CeO 2 -500 is most catalytically active while r-CeO 2 -700 is least. The acetylene semihydrogenation reaction catalyzed by various CeO 2 nanocrystals was observed to follow the same reaction mechanism. C 2 H 2 adsorbs at both O and Ce sites on CeO 2 surfaces to form C 2 H 2 (a) species that facilely hydrogenates stepwise to C 2 H 3 (a) and C 2 H 4 (a). The surface hydrogenation reactions proceed more facilely at the O site than at the Ce site. The desorption of C 2 H 4 (a) proceeds slowly and is the rate-limiting step. c-CeO 2 , r-CeO 2 -500 and r-CeO 2 -700 do not exhibit obvious differences among these elementary surface reactions, but show much different abilities to dissociate H 2 and chemisorb C 2 H 2. The C 2 H 2 (a) coverage follows an order of r-CeO 2 -500 ≫ c-CeO 2 ≈ r-CeO 2 -700. The ability to dissociate H 2 follows an order of c-CeO 2 > r-CeO 2 -500 ≫ r-CeO 2 -700. The observed morphology-dependent behaviors of various CeO 2 nanocrystals were correlated to their defects and exposed facets. These results successfully demonstrate morphology-dependent CeO 2 catalysis in acetylene semihydrogenation reaction and elucidate the underlying mechanisms. [ABSTRACT FROM AUTHOR]