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Almost all marine organisms contain both inorganic and organic mercury, and thus it is extremely important to determine mercury species in seafood to objectively and scientifically assess the health risk posed by mercury.

The phylogeny of the species from Phrymaceae and Mazaceae has undergone many adjustments and changes in recent years. Moreover, there is little plastome information on the Phrymaceae. In this study, we compared the plastomes of six species from the Phrymaceae and 10 species from the Mazaceae. The gene order, contents, and orientation of the 16 plastomes were found to be highly similar. A total of 13 highly variable regions were identified among the 16 species. An accelerated rate of substitution was found in the protein-coding genes, particularly cemA and matK. The combination of effective number of codons, parity rule 2, and neutrality plots revealed that the codon usage bias is affected by mutation and selection. The phylogenetic analysis strongly supported {Mazaceae [(Phrymaceae + Wightiaceae) + (Paulowniaceae + Orobanchaceae)]} relationships in the Lamiales. Our findings can provide useful information to analyze the phylogeny and molecular evolution within the Phrymaceae and Mazaceae.

Background: Gouty arthritis (GA) is a common form of inflammatory arthritis caused by intra-articular deposition of monosodium urate (MSU) crystals; however, there is a tremendous lack of safe and effective therapy in the clinic. Objective: The goal of this work was to investigate a novel leflunomide analogue, N-(2,4-dihydroxyphenyl)-5-methyl -1,2-oxazole-3-carboxamide (UTLOH-4e), for its potential to prevent/treat gouty arthritis. Methods: In this study, the anti-inflammatory activity of UTLOH-4e was evaluated by MSU-induced GA model in vivo and in vitro, and the molecular docking test was applied to estimate the affinity of UTLOH-4e/UTL-5g/b for MAPKs, NF-κB, and NLRP3. Results: In vitro, UTLOH-4e (1~100 M) treatment inhibited the inflammatory reaction with no obvious cytotoxicity in PMA-induced THP-1 macrophages exposed to MSU crystals for 24 h, involving the prominent decreased production and gene expression of IL-1β, TNF-, and IL-6. Western blot analyses demonstrated that UTLOH-4e (1~100 M) significantly suppressed the activation of NLRP3 inflammasomes, NF-κB, and MAPK pathways. Furthermore, the data from the experiment on gouty rats induced by intra-articular injection of MSU crystal confirmed that UTLOH-4e markedly ameliorated rat paw swelling, articular synovium inflammation and reduced the concentration of IL-1β and TNF- in serum through down-regulating NLRP3 protein expression. Conclusion: These results manifested that UTLOH-4e ameliorates GA induced by MSU crystals, which contributes to the modulation of NF-B/ NLRP3 signaling pathway, suggesting that UTLOH-4e is a promising and potent drug candidate for the prevention and treatment of gouty arthritis.

A new disease designated as Pale liver disease (PLD) has been circulating in Chinese Muscovy duck flocks since 2014, which is characterized by fatigue, diarrhoea, sudden death and acute hepatitis with pale and haemorrhagic liver. In this study, the etiological agents of PLD were isolated, causing a significant cytopathic effect (CPE) by cell rounding. Virus particles were observed by transmission electron microscopic (TEM) observation. The same disease was reproduced by experimental infection with the isolate BG61. The whole genomes of isolates were 43,842 nt in length with a GC content of 47.11%, similar to French Muscovy duck adenovirus strain GR with a GC content of 46.08%. The isolates shared 99.71-99.95% and 93.31-93.33% identity with Chinese Muscovy duck adenovirus isolates and GR strain, respectively. The DNA polymerase gene of all Muscovy duck adenovirus strains formed a separate genetic lineage with 99.55-100% amino acid sequence identity. All Chinese Muscovy duck adenovirus isolates contained two fibre genes. In contrast, only one fibre gene was found in GR, the only representative strain in species Duck aviadenovirus B. Anti-DAdV-2 serum antibodies had a weak neutralizing activity against Chinese Muscovy duck adenovirus isolates. The phylogenetic trees of the complete genome, hexon and fibre proteins revealed that all Muscovy duck adenovirus strains formed a major genetic lineage consisting of two clades. Thus, both GR and Chinese Muscovy duck adenovirus strains were proposed to be included in the same species of Duck aviadenovirus B belonging to the genus Aviadenovirus. The species Duck aviadenovirus B included two serotypes or genotypes, such as GR, which represents the strain of serotype 1 or genotype 1 (DAdV B1) and Chinese Muscovy duck adenovirus strains, which belong to serotype 2 or genotype 2 (DAdV B2).

Genus Comastoma (subt. Swertiinae, Gentianaceae) contains species, such as “Zangyinchen,” that are important herbs in Tibetan medicine. The phylogenetic relationship of this within Gentianaceae and the circumscriptions of its species have long been controversial with conflicting morphological and molecular data reported. Here, we used whole chloroplast genome sequences for Comastoma species and related taxa to reconstruct their phylogeny and clarify their taxonomic relationships. The results revealed that the length of all plastome sequenced varied from 149 to 151 kb and have high similarity in structure and gene content. Phylogenomic analysis showed that Comastoma is a monophyletic group, closely related to the genus Lomatogonium. The divergence time estimation showed that Gentianaceae diverged at about 21.81 Ma, while the split of Comastoma occurred at 7.70 Ma. However, the results suggested the crown age of species formation in this genus is after 4.19 Ma. Our results suggest that QTP uplift, the alternation of Quaternary glaciation and interglaciation, and monsoon changes might have acted as drivers of speciation in Comastoma.

Comprising ca. 200 species

Supported gold nanoparticles are widely studied catalysts and are among the most active known for the low-temperature water–gas shift reaction, which is essential in fuel and energy applications, but their practical application has been limited by their poor thermal stability. The catalysts deactivate on-stream via the growth of small Au nanoparticles. Using operando X-ray absorption and in situ scanning transmission electron microscopy, we report direct evidence that this process can be reversed by carrying out a facile oxidative treatment, which redisperses the gold nanoparticles and restores catalytic activity. The use of in situ methods reveals the complex dynamics of supported gold nanoparticles under reaction conditions and demonstrates that gold catalysts can be easily regenerated, expanding their scope for practical application.

PurposeThe construction industry is facing challenges not only for workers' mobility in the pandemic situation but also for Lean Construction (LC) practise in responding to the high-quality development during the post-pandemic. As such, this paper presents a construction workforce management framework based on LC to manage both the emergency goal in migrant worker management and the long-term goal in labour productivity improvement in China.Design/methodology/approachThe framework is created based on the integrated culture and technology strategies of LC. A combination of qualitative and quantitative methods is taken to explore factors influencing the mobility of construction workers and to measure labour productivity improvement. The case study approach is adopted to demonstrate the framework application.FindingsFor method application, a time-and-motion study and Percent Plan Complete indicator are proposed to offer labour productivity measurements of “resources efficiency” and “flow efficiency”. Moreover, the case study provides an industry level solution for construction workforce management and Lean Construction culture shaping, as well as witnesses the LC culture and technology strategies alignment contributing to LC practise innovation.Originality/valueCompared with previous studies which emphasised solely LC techniques rather than socio-technical system thinking, the proposed integration framework as well as implementation of “Worker's Home” and “Lean Work Package” management models in the COVID-19 pandemic contribute to new extensions of both the fundamental of knowledge and practise in LC.

H146-like goose-origin calicivirus (H146-like GCV) is a novel Caliciviridae family member in the Sanovirus genus that was recently discovered and proposed to cause runting-stunting syndrome and urate deposition in geese. At present, however, there is a lack of epidemiological information pertaining to the dynamics and distribution of H146-like GCV. The development of novel molecular diagnostic approaches capable of rapidly and accurately detecting this virus would support the strengthening, the prevention, and control of H146-like GCV infection. In the present study, we therefore used a TaqMan probe and primers specific for the viral nonstructural (NS) gene to develop a highly sensitive and specific PCR assay capable of detecting this H146-like GCV. The assay reproducibly detected 5.07 × 102 copies of a recombinant DNA plasmid containing the NS gene, with a dynamic range of 8 orders of magnitude (102–109 copies). Importantly, no cross-reactivity was observed with common viruses that affected waterfowl, and when we used this assay to evaluate clinical samples, we found it to be more sensitive and faster than traditional PCR. In summary, herein, we developed a novel TaqMan-based real-time PCR approach that could reliably detect and diagnose H146-like GCV. This tool will allow for the real-time diagnosis of H146-like GCV infections, enabling researchers to better understand the epidemiology and clinical presentation of this disease.

Background. Gout is a common crystal-related arthritis caused by the deposition of monosodium urates (MSU). Tibetan medicine Wuwei Shexiang Pills (WSP) has been demonstrated to exhibit anti-inflammatory, antihyperuricemia, and antigout activities. However, the underlying mechanism is unknown. Objectives. To explore the mechanisms of Wuwei Shexiang Pills on gouty arthritis via network pharmacology, molecule docking, and pharmacological verification. Methods. The ingredients and targets of WSP were obtained by searching and screening in BATMAN-TCM and SwissADME. The targets involving the gout were acquired from public databases. The shared targets were put onto STRING to construct a PPI network. Furthermore, Metascape was applied for the GO and KEGG enrichment analysis to predict the biological processes and signaling pathways. And molecular docking was performed to validate the binding association between the key ingredients and the relative proteins of TNF signaling. Based on the serum pharmacology, the predicted antigout mechanism of WSP was validated in MSU-induced THP-1 macrophages. The levels of inflammatory cytokines and mRNA were measured by ELISA and qRT-PCR, respectively, and MAPK, NF-κB, and NLRP3 signaling-associated proteins were determined by western blot and immunofluorescence staining. Results. 48 bioactive ingredients and 165 common targets were found in WSP. The data showed that 5-Cis-Cyclopentadecen-1-One, 5-Cis-Cyclotetradecen-1-One, (−)-isoshyobunone, etc. were potential active ingredients. TNF signaling, HIF-1 signaling, and Jak-STAT signaling were predicted to be the potential pathways against gout. The molecule docking analysis found that most ingredients had a high affinity for p65, NLRP3, IL-1β, TNF-α, and p38. The data from in vitro experiment showed that WSP suppressed the production and gene expression of inflammatory cytokines. Furthermore, WSP could inhibit the activation of MAPK, NF-κB, and NLRP3 signaling pathways. Conclusion. Our finding suggested that the antigout effect of WSP could be achieved by inhibiting MAPK, NF-κB, and NLRP3 signaling pathways. WSP might be a candidate drug for gouty treatment.

Triosteum himalayanum, Triosteum pinnatifidum (Triosteum L., Caprifoliaceae, Dipsacales) are widely distributed in China while Triosteum sinuatum mainly occurrs in northeast China. Few reports have been determined on the genus Triosteum. In the present research, we sequenced 2 chloroplast genomes of Triosteum and analyzed 18 chloroplast genomes, trying to explore the sequence variations and phylogeny of genus Triosteum in the order Dipsacales. The chloroplast genomes of the genus Triosteum ranged from 154,579 bp to 157,178 bp, consisting of 132 genes (86 protein-coding genes, 38 transfer RNA genes, and 8 ribosomal RNA genes). Comparative analyses and phylogenetic analysis supported the division of Dipsacales into two clades, Adoxaceae and six other families. Among the six families, a clade of Valerianaceae+Dipsacaceae was recovered as a sister to a clade of Morinaceae+Linnaeaceae. A closer relationship of T. himalayanum and T. pinnatifidum among three species was revealed. Our research supported that Loniceraferdinandi and Triosteum was closely related. Zabelia had a closer relationship with Linnaea borealis and Dipelta than Morinaceae. The divergence between T. sinuatum and two other species in Triosteum was dated to 13.4 mya.

The difficulty of effectively monitoring and managing the environment to conserve biodiversity is as yet an unsolved conundrum. A project of the Chinese Academy of Sciences has concluded that progress can be made through the use of flagship species selected using criteria drawn from conservation biology, ecosystem function, socio-economics, and cultural importance. Inclusion of the latter three criteria will help attract and maintain the commitment of the public to play full parts in carrying out any conservation measures needed. A system is proposed for scoring species to select those that are most suitable as flagships. This method can be used regardless of the size of the area chosen for attention, whether it is a region, a country, or a particular protected area., Highlights • Solve conservation problem. • Criteria to select flagship species. • Scoring system. • Governance of biodiversity.

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.

Aiming at a detailed understanding of the size-dependent Au active structure and reaction mechanism for the low-temperature propene epoxidation with H2 and O2, we have prepared and studied the Au c...

Background:Tropane Alkaloids (TAs) are important drugs for curing many diseases in the medical industry.Methods:To sustainably exploit TA resources in endangered traditional Tibetan herbs, the hairy root (HR) systems of Przewalskia tangutica Maxim. and Anisodus tanguticus Maxim. were compared under the same culture conditions.Results:The results indicated that both the Agrobacterium rhizogenes strains and explants affected the HR induction frequency, MSU440, A4 and LBA9402 strains could induce hairy roots following infection of cotyledon and hypocotyl of A. tanguticus while LBA9402 could not induce HR on either explants of P. tangutica. The efficiency of LBA9402 was higher than A4 and MSU440 on A. tanguticus and A4 was better strain than MSU440 on P. tangutica. The hypocotyl explant was more suitable for P.tangutica and cotyledon explant was better for A.tangutica with a transformation frequency of 33.3% (P. tangutica) and 82.5% (A. tanguticus), respectively. In a flask reactor system, both the growth curves of HR for two species both appeared to be “S” curve; however, the HR of P. tangutica grew more rapidly than that of A. tanguticus, and the latter accumulated more biomass than the former. As the culture volume increased, the HR proliferation coefficient of both the species increased. HPLC analysis results showed that the content of TAs in the HR of P. tangutica was 257.24mg/100g·DW, which was more than that of A. tanguticus HR (251.08mg/100g·DW), and the anisodamine in the Pt- HR was significantly higher than that in At-HR. Moreover, tropane alkaloids in the HR of the two species were all significantly higher than that of the roots of aseptic seedlings.Conclusion:Our results suggest that HR of P. tangutica and A. tanguticus both could provide a useful platform for sustainable utilization of two Tibetan medicinal plants in the Qinghai-Tibetan Plateau in the future.

Background and AimsHosting several global biodiversity hotspots, the region of the Qinghai-Tibetan Plateau (QTP) is exceptionally species-rich and harbours a remarkable level of endemism. Yet, despite a growing number of studies, factors fostering divergence, speciation and ultimately diversity remain poorly understood for QTP alpine plants. This is particularly the case for the role of hybridization. Here, we explored the evolutionary history of three closely related Gentiana endemic species, and tested whether our results supported the mountain geo-biodiversity hypothesis (MGH).MethodsWe genotyped 69 populations across the QTP with one chloroplast marker and 12 nuclear microsatellite loci. We performed phylogeographical analysis, Bayesian clustering, approximate Bayesian computation and principal components analysis to explore their genetic relationship and evolutionary history. In addition, we modelled their distribution under different climates.Key ResultsEach species was composed of two geographically distinct clades, corresponding to the south-eastern and north-western parts of their distribution. Thus Gentiana veitchiorum and G. lawrencei var. farreri, which diverged recently, appear to have shared at least refugia in the past, from which their range expanded later on. Indeed, climatic niche modelling showed that both species went through continuous expansion from the Last Interglacial Maximum to the present day. Moreover, we have evidence of hybridization in the northwest clade of G. lawrencei var. farreri, which probably occurred in the refugium located on the plateau platform. Furthermore, phylogenetic and population genetic analyses suggested that G. dolichocalyx should be a geographically limited distinct species with low genetic differentiation from G. lawrencei var. farreri.ConclusionsClimatic fluctuations in the region of the QTP have played an important role in shaping the current genetic structure of G. lawrencei var. farreri and G. veitchiorum. We argue that a species pump effect did occur prior to the Last Interglacial Maximum, thus lending support to the MGH. However, our results do depart from expectations as suggested in the MGH for more recent distribution range and hybridization dynamics.

Muscovy duck reovirus (MDRV) is highly pathogenic to young Muscovy ducklings. Although MDRV infection results in ducklings' acute watery diarrhea, the effect of MDRV infection on the composition of host's intestinal microbiota remains poorly understood. This study was conducted to investigate the impacts of MDRV on the composition of Muscovy ducklings' intestinal bacterial community. Three-day-old Muscovy ducklings were inoculated with either the virulent MDRV strain MW9710 or sterile Hank's solution, respectively. The cecal microbiota was analyzed between control and mock MDRV-infected ducklings using Illumina MiSeq sequencing at 6 dpi and 17 dpi, respectively. The results indicated that MDRV infection damaged the intestinal mucosa. In addition, MDRV infection caused severe perturbations of gut microbiota by decreasing microbial richness, altering the abundance of certain genera of the gut microbiota at 6 dpi. Specifically, the relative abundance of short chain fatty acids-producing bacteria (including Shuttleworthia, Streptococcus, and Ruminococcus) was reduced in MDRV-infected ducklings than those of control group, whereas, with an enrichment of Enterobacteriaceae (including Plesiomonas, Escherichia_Shigella and Proteus). Furthermore, microbiota analysis showed that the gut microbiota dysbiosis caused by MDRV infection was basically recovered at 17 dpi. Collectively, this study demonstrated that the gut microbiota of Muscovy ducklings were altered due to MDRV infection, mainly featuring as a net loss of beneficial bacteria and a compensatory proliferation of pathogenic bacteria, which may lead to severe pathology to the intestinal mucosa, and ultimately acute diarrhea. These results will provide insights into the pathology of MDRV infection.

Solanum japonense Nakai. (Solanaceae) is a traditional Chinese medicine and animal fodder in Asian continent. Here, the complete chloroplast genome sequence of S. japonense was determined by the Il...

The emergence of drug resistance is one of the main obstacles to the treatment of lung cancer patients with EGFR inhibitors. Here, to further understand the mechanism of EGFR inhibitors in lung cancer and offer novel therapeutic targets for anti-EGFR-inhibitor resistance via the deep mining of pharmacogenomics data, we associated DNA methylation with drug sensitivities for uncovering the methylation sites related to EGFR inhibitor sensitivity genes. Specifically, we first introduced a grouped regularized regression model (Group Least Absolute Shrinkage and Selection Operator, group lasso) to detect the genes that were closely related to EGFR inhibitor effectiveness. Then, we applied the classical regression model (lasso) to identify the methylation sites associated with the above drug sensitivity genes. The new model was validated on the well-known cancer genomics resource: CTRP. GeneHancer and Encyclopedia of DNA Elements (ENCODE) database searches indicated that the predicted methylation sites related to EGFR inhibitor sensitivity genes were related to regulatory elements. Moreover, the correlation analysis on sensitivity genes and predicted methylation sites suggested that the methylation sites located in the promoter region were more correlated with the expression of EGFR inhibitor sensitivity genes than those located in the enhancer region and the TFBS. Meanwhile, we performed differential expression analysis of genes and predicted methylation sites and found that changes in the methylation level of some sites may affect the expression of the corresponding EGFR inhibitor-responsive genes. Therefore, we supposed that the effectiveness of EGFR inhibitors in lung cancer may be improved by methylation modification in their sensitivity genes.

Saxifraga sinomontana J.-T. Pan & Gornall belongs to Saxifraga sect. Ciliatae subsect. Hirculoideae, a lineage containing ca. 110 species whose phylogenetic relationships are largely unresolved due to recent rapid radiations. Analyses of complete chloroplast genomes have the potential to significantly improve the resolution of phylogenetic relationships in this young plant lineage. The complete chloroplast genome of S. sinomontana was de novo sequenced, assembled and then compared with that of other six Saxifragaceae species. The S. sinomontana chloroplast genome is 147,240 bp in length with a typical quadripartite structure, including a large single-copy region of 79,310 bp and a small single-copy region of 16,874 bp separated by a pair of inverted repeats (IRs) of 25,528 bp each. The chloroplast genome contains 113 unique genes, including 79 protein-coding genes, four rRNAs and 30 tRNAs, with 18 duplicates in the IRs. The gene content and organization are similar to other Saxifragaceae chloroplast genomes. Sixty-one simple sequence repeats were identified in the S. sinomontana chloroplast genome, mostly represented by mononucleotide repeats of polyadenine or polythymine. Comparative analysis revealed 12 highly divergent regions in the intergenic spacers, as well as coding genes of matK, ndhK, accD, cemA, rpoA, rps19, ndhF, ccsA, ndhD and ycf1. Phylogenetic reconstruction of seven Saxifragaceae species based on 66 protein-coding genes received high bootstrap support values for nearly all identified nodes, suggesting a promising opportunity to resolve infrasectional relationships of the most species-rich section Ciliatae of Saxifraga.

Ru/TiO2 catalysts exhibit an exceptionally high activity in the selective methanation of CO in CO2 - and H2 -rich reformates, but suffer from continuous deactivation during reaction. This limitation can be overcome through the fabrication of highly active and non-deactivating Ru/TiO2 catalysts by engineering the morphology of the TiO2 support. Using anatase TiO2 nanocrystals with mainly {001}, {100}, or {101} facets exposed, we show that after an initial activation period Ru/TiO2 -{100} and Ru/TiO2 -{101} are very stable, while Ru/TiO2 -{001} deactivates continuously. Employing different operando/in situ spectroscopies and ex situ characterizations, we show that differences in the catalytic stability are related to differences in the metal-support interactions (MSIs). The stronger MSIs on the defect-rich TiO2 -{100} and TiO2 -{101} supports stabilize flat Ru nanoparticles, while on TiO2 -{001} hemispherical particles develop. The former MSIs also lead to electronic modifications of Ru surface atoms, reflected by the stronger bonding of adsorbed CO on those catalysts than on Ru/TiO2 -{001}.

Aiming at a more detailed understanding of support effects on the catalytic performance of supported Ru catalysts, here specifically in the selective methanation of CO, we have prepared and investigated a set of three isostructural Ru catalysts with different supports (TiO2, Al2O3, and ZrO2), but similar surface area, Ru loading, and Ru particle size. The activity was found to increase with increasing reducibility in the order Ru/Al2O3 ≤ Ru/ZrO2 , which goes along with a significant increase of electron density on the Ru NPs, in the number of O-vacancies, and the amount of basic sites in the oxide supports, as probed by XPS and pyrrole titration. In situ FTIR spectra recorded during reaction indicate that the high activity on Ru/TiO2 is correlated with the highest COad/Ru-multicarbonyl coverage, while Ru/ZrO2 and Ru/Al2O3 exhibit significantly lower COad coverages, indicative of lower CO adsorption energies. Kinetic measurements using isotope labelled gas mixtures, H2/CO and D2/CO, show a small, but distinct inverse kinetic isotope effect (KIE), which is more pronounced on Ru/TiO2 (RH/RD = 0.76) than on Ru/ZrO2 and Ru/Al2O3 ((RH/RD = 0.91). These trends are explained by and discussed in terms of differences in electronic metal-support interactions (EMSIs), caused by the differences in O-vacancy formation (reducibility) of the support materials and consequently in charge transfer to the Ru nanoparticles. Such effects are considered to be of general importance for reactions taking place under strongly reductive conditions.

Au nanoparticles with different loadings were prepared on anatase TiO2 nanocrystals with various morphologies predominantly exposing {001} facets (denoted as TiO2{001}), {100} facets (denoted as TiO2{100}) and {101} facets (denoted as TiO2{001}) by the deposition–precipitation method. Sizes, structures, and catalytic activity in low-temperature CO oxidation of the resulting Au/TiO2 catalysts were comprehensively characterized. Nucleation, growth, and agglomeration of Au particles on TiO2 supports were observed to depend on TiO2 morphologies due to the morphology-dependent defect structures of TiO2 nanocrystals and subsequent Au–TiO2 interactions. Au particles mainly homogeneously nucleate and grow on these three TiO2 nanocrystals with Au loadings of 0.2–1%. With the increase in Au loadings to 2 and 5%, Au particles mainly agglomerate on TiO2{001}, mainly homogeneously nucleate and grow on TiO2{100}, and both nucleate and grow and slightly agglomerate on TiO2{101}. The electronic effect of supported Au par...

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. 3Dh, 5Dh, 10Dh, 15Dh and 20Dh 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 10Dh downstream of the spacer grid and then damped gradually.

The Hoh Xil basin is the largest Cenozoic sedimentary basin in the Qinghai–Tibet Plateau (QTP) with an average altitude of above 5000 m. It is also the coldest region in the QTP. However, due to the difficulty of sample collection caused by the harsh natural environment, a limited number of studies have been conducted on soil microorganisms in this region. We used culture-dependent and independent methods to investigate the bacterial communities in desert soil (n1), saline–alkali land (n2), saline–alkali wetland (n3), and soda lake sediment (n4). The results showed distinct bacterial communities between different environmental types. We found that the Chao1 and Shannon diversity indices of n1 were significantly lower than those of n4 (P

Significance Permafrost degradation may induce soil carbon (C) loss, critical for global C cycling, and be mediated by microbes. Despite larger C stored within the active layer of permafrost regions, which are more affected by warming, and the critical roles of Qinghai–Tibet Plateau in global C cycling, most previous studies focused on the permafrost layer and in high-latitude areas. Here, we demonstrate in situ that permafrost degradation alters the diversity and potentially decreases the stability of active layer microbial communities. Additionally, these changes are associated with soil C loss and potentially a positive C feedback. This study provides insights into microbial-mediated mechanisms responsible for C loss within the active layer in degraded permafrost, aiding in the modeling of C emission under future scenarios.

Background The genus Swertia is of great medicinal importance and one of the most taxonomically challenging taxa within Gentianaceae, largely due to the morphological similarities of species within this genus and with its closely related genera. Previous molecular studies confirmed its polyphyly but suffered from low phylogenetic resolutions because only limited sequence loci were used. Thus, we conducted the structural, gene evolutionary, and phylogenetic analyses of 11 newly obtained plastomes of Swertia. Our result greatly improved the phylogenetic resolutions in Swertia, shed new light on the plastome evolution and phylogenetic relationships of this genus. Results The 11 Swertia plastomes together with the published seven species proved highly similar in overall size, structure, gene order, and content, but revealed some structural variations caused by the expansion and contraction of the IRb region into the LSC region, due to the heterogeneous length of the ψycf1. The gene rps16 was found to be in a state flux with pseudogenes or completely lost. Similar situation was also documented in other genera of Gentianaceae. This might imply loss of the gene in the common ancestor of Gentianaceae. The distribution plot of ENC vs. GC3 showed all these plastomes arranging very close in the Wright line with an expected ENC value (49–52%), suggesting the codon usage of Swertia was mainly constrained by a GC mutation bias. Most of the genes remained under the purifying selection, however, the cemA was identified under positive selection, possibly reflecting an adaptive response to low CO2 atmospheric conditions during the Late Miocene. Our phylogenomic analyses, based on 74 protein-coding genes (CDS), supported the polyphyly of Swertia with its close allies in the subtribe Swertiinae, presumably due to recent rapid radiation. The topology inferred from our phylogenetic analyses partly supported the current taxonomic treatment. Finally, several highly variable loci were identified, which can be used in future phylogenetic studies and accurate identification of medicinal genuineness of Swertia. Conclusions Our study confirmed the polyphyly of Swertia and demonstrated the power of plastome phylogenomics in improvement of phylogenetic resolution, thus contributing to a better understanding of the evolutionary history of Swertia.

The discovery of the activity of dispersed gold nanoparticles three decades ago paved the way for a new era in catalysis. The unusual behavior of these catalysts sparked many questions about their working mechanism. In particular, Au/CeO2 proved to be an efficient catalyst in several reactions such as CO oxidation, water gas shift, and CO2 reduction. Here, by employing findings from operando X‐ray absorption spectroscopy at the near and extended Au and Ce LIII energy edges, we focus on the fundamental aspects of highly active Au/CeO2 catalysts, mainly in the CO oxidation for understanding their complex structure‐reactivity relationship. These results were combined with findings from in situ diffuse reflectance FTIR and Raman spectroscopy, highlighting the changes of adlayer and ceria defects. For a comprehensive understanding, the spectroscopic findings will be supplemented by results of the dynamics of O2 activation obtained from Temporal Analysis of Products (TAP). Merging these results illuminates the complex relationship among the oxidation state, size of the Au nanoparticles, the redox properties of CeO2 support, and the dynamics of O2 activation., Unravelling the mystery of Au/CeO2 catalysts! Challenged by the complex nature of Au/CeO2 catalysts, operando X‐ray absorption spectroscopy in the near and extended Au LIII and Ce LIII energy edges is employed to decipher different aspects of the electronic and geometric features of Au NPs/clusters and CeO2 support. These results combined with findings from ex‐situ XPS, in situ FTIR/Raman spectroscopy and temporal analysis of products (TAP) reactor, provide a more fundamental insight into the performance of these catalysts.