Structural dynamic model updating based on Kriging model using frequency response data

Metamodel technique is attracting more and more attention in structural dynamic model updating. In this paper, an attempt is made to explore the effectiveness of Kriging method for acceleration frequency response function based model updating. A Kriging model is constructed based on the input variables selected by F-test method specially, which is applied to the results of design of experiment. The response of design of experiment is obtained based on the errors between acceleration response curves of analytical model and experimental model. Two examples of representative structure are discussed, the comparison of updated results of different metamodel shows that a less error of updated results can be obtained based on Kriging model, and the updated analytical model has a good prediction capability. It can be concluded that the Kriging model is suitable for the frequency response function based model updating

A Schematic Discoursal Study of Chinese Football Players’ Commercial Transfer News

This cognitive discoursal study explores human cognitive mechanisms by analyzing Football Players’ Commercial Transfer News (FPCTN) through adopting Gibbs’ (2010) embodied view of image schemas in language use and their interpretations in Chinese sports contexts, based on the database of 36 pieces of news reports collected from authoritative sports websites. The results demonstrate that FPCTN writers actively construct their meanings and perspectives by applying various metaphysical and metaphysicalized forms of image schemas, which are grounded on our knowledge and daily bodily experience. Discourse consumers, on the other hand, unconsciously engage themselves in imaginative simulation processes, which are fundamentally embodied in their past and present bodily experiences, to facilitate their understanding of linguistic information and writers’ intentions, which predicates the process of public general cognition construction and frame, meanwhile, constituting the mechanism of a news reader’s passionate identification with and attachment to a potential commodity in his/her social and entertainment life

Synthesis and characterization of styrene-based polyfluoroacrylate film for hydrophobic/icephobic applications

Low surface energy polymeric materials always attract great interest due to their effective non-stick feature when contacting with other materials. In the present work, hydrophobic polyfluoroacrylates (PFAs) were synthesized using styrene, acrylic acid, and heptafluorobutyl acrylate via radical polymerization. The synthesized PFA emulsions had a relatively low curing temperature (e.g. 80 °C), and different molar ratios of heptafluorobutyl acrylate were used to vary the fluorine content in the PFAs. From chemical analysis by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and nuclear magnetic resonance, it was found that the synthesized PFA emulsion exhibited co-polymer structure consisting of the three monomer units. PFA films were deposited on aluminium substrates by spin coating of the synthesized emulsions. The hydrophobicity of the films varied with the fluorine content, and a maximum water contact angle of 121° was achieved under relatively smooth surface condition. Ice adhesion of the PFA films was also evaluated using a centrifugal method, and the ice adhesion strength decreased with the increase of the fluorine content in PFA

Advances in the Bacteriophage-Based Precise Identification and Magnetic Relaxation Switch Sensor for Rapid Detection of Foodborne Pathogens

The development of novel and highly specific technologies for the rapid and sensitive detection of foodborne pathogens is very important for disease prevention and control. Bacteriophages can recognize viable and unviable bacteria, replacing antibodies as the recognition element in the immune response, which are currently being widely developed in novel precise identification biosensors. Magnetic relaxation switch sensors based on the magnetic relaxation signal has been used to construct a variety of background-free novel biosensors in recent years, which can realize rapid detection of foodborne pathogens. This chapter will mainly introduce the latest developments and future prospects of bacteriophages in the field of accurate identifications for foodborne pathogens. At the same time, it will introduce the research progress and development direction of novel magnetic relaxation switch sensors for detecting foodborne pathogens

Effects of Resveratrol on Superficial Scald of 'Dangshansuli' Pears

The effects of resveratrol (Res) on the quality and superficial scald of ‘Dangshansuli’ pears (Pyrus bretchnederi Rehd.) during cold storage (0±0.5°C) and shelf life (20°C) were investigated. The results showed that treatments with 0.1, 1.0, 10 and 100 mg L-1 Res significantly delayed the decrease of firmness, soluble solids contents (SSC), juice rate, reduced the relative conductivity, MDA, α-farnesene and conjugated trienes in the cold storage. At the end of 210 d storage, α-farnesene of control, 0.1, 1.0, 10 and 100 mg L-1 Res treatments were 14.81, 11.0, 10.49, 9.31 and 11.4 nmol cm-2, respectively. Whereas conjugated trienes were 6.38, 4.17, 4.04, 3.67 and 4.39 nmol cm-2 respectively. After 210 d, the scald incidence of control, 0.1, 1.0, 10 and 100 mg L-1 Res treatment were 45.5%, 4.3%, 0%, 0% and 7.1%, respectively, and their scald index were 18.2%, 2.9%, 0%, 0% and 3.1%, respectively. After additional 7 d at 20°C, scald incidence successively were 100%, 21.4%, 22.4%, 14.1% and 20.9%, while the scald index were 71.2%, 23.3%, 22.9%, 15.4% and 22.8%, respectively. Res treatments maintained the quality and inhibited superficial scald, and 10 mg L-1 Res was the optimum treatment. Thus, it is likely that Res can serve as a potential antioxidant for the preservation and storage of postharvest ‘Dangshansuli’ pears

Elevational distribution and seasonal dynamics of alpine soil prokaryotic communities

The alpine grassland ecosystem is a biodiversity hotspot of plants on the Qinghai-Tibetan Plateau, where rapid climate change is altering the patterns of plant biodiversity along elevational and seasonal gradients of environments. However, how belowground microbial biodiversity changes along elevational gradient during the growing season is not well understood yet. Here, we investigated the elevational distribution of soil prokaryotic communities by using 16S rRNA amplicon sequencing along an elevational gradient between 3,200 and 4,200 m, and a seasonal gradient between June and September in the Qinghai-Tibetan alpine grasslands. First, we found soil prokaryotic diversity and community composition significantly shifted along the elevational gradient, mainly driven by soil temperature and moisture. Species richness did not show consistent elevational trends, while those of evenness declined with elevation. Copiotrophs and symbiotic diazotrophs declined with elevation, while oligotrophs and AOB increased, affected by temperature. Anaerobic or facultatively anaerobic bacteria and AOA were hump-shaped, mainly influenced by moisture. Second, seasonal patterns of community composition were mainly driven by aboveground biomass, precipitation, and soil temperature. The seasonal dynamics of community composition indicated that soil prokaryotic community, particularly Actinobacteria, was sensitive to short-term climate change, such as the monthly precipitation variation. At last, dispersal limitation consistently dominated the assembly process of soil prokaryotic communities along both elevational and seasonal gradients, especially for those of rare species, while the deterministic process of abundant species was relatively higher at drier sites and in drier July. The balance between deterministic and stochastic processes in abundant subcommunities might be strongly influenced by water conditions (precipitation/moisture). Our findings suggest that both elevation and season can alter the patterns of soil prokaryotic biodiversity in alpine grassland ecosystem of Qinghai-Tibetan Plateau, which is a biodiversity hotspot and is experiencing rapid climate change. This work provides new insights into the response of soil prokaryotic communities to changes in elevation and season, and helps us understand the temporal and spatial variations in such climate change-sensitive regions

Molecular Docking of Potential Inhibitors for Influenza H7N9

As a new strain of virus emerged in 2013, avian influenza A (H7N9) virus is a threat to the public health, due to its high lethality and pathogenicity. Furthermore, H7N9 has already generated various mutations such as neuraminidase R294K mutation which could make the anti-influenza oseltamivir less effective or ineffective. In this regard, it is urgent to develop new effective anti-H7N9 drug. In this study, we used the general H7N9 neuraminidase and oseltamivir-resistant influenza virus neuraminidase as the acceptors and employed the small molecules including quercetin, chlorogenic acid, baicalein, and oleanolic acid as the donors to perform the molecular docking for exploring the binding abilities between these small molecules and neuraminidase. The results showed that quercetin, chlorogenic acid, oleanolic acid, and baicalein present oseltamivir-comparable high binding potentials with neuraminidase. Further analyses showed that R294K mutation in neuraminidase could remarkably decrease the binding energies for oseltamivir, while other small molecules showed stable binding abilities with mutated neuraminidase. Taken together, the molecular docking studies identified four potential inhibitors for neuraminidase of H7N9, which might be effective for the drug-resistant mutants