Diversity and Identification of Yeasts Isolated from Tumultuous Stage of Spontaneous Table Grape Fermentations in Central China

Table grapes are of increasing interest for wine production in China. In this study, 480 yeast isolates were isolated from the tumultuous stage during the spontaneous fermentation of six table grape varieties, which were cultivated in an ecological environment that was not industry-influenced, in Central China.  The 26S rDNA D1/D2 domain sequence analysis was more efficient for yeast species identification than the 5.8S-ITS region RFLP analysis in the present study. All the tested strains belonged to nine species from six genera: Hanseniaspora guilliermondii, H. opuntiae, H. uvarum, Pichia terricola, Kazachstania hellenica, K. zonata, P. occidentalis, Saccharomyces cerevisiae and Zygosaccharomyces bailii. The yeast species and populations differed notably among the grape varieties. S. cerevisiae was found in the samples of four grape varieties (Vitis amurensis, Iona, Moldova and V. davidii), but not detected in Cuihong and Alimandeng Rose. Interdelta sequence fingerprinting analysis was used to discriminate between 128 S. cerevisiae isolates. Eight S. cerevisiae genotypes (G1 to G8) were distinguished. Genotypes G1, G2, and G3 were the most dominant strains, accounting for 32.03%, 24.22% and 28.13% of the isolates respectively.  This study shows the diversity of yeast species associated with spontaneous fermentations of different table grape varieties grown in an ecological environment without any wine industry effect or footprint

Momentum Distribution of Near-Zero-Energy Photoelectrons in the Strong-Field Tunneling Ionization in the Long Wavelength Limit

We investigate the ionization dynamics of Argon atoms irradiated by an ultrashort intense laser of a wavelength up to 3100 nm, addressing the momentum distribution of the photoelectrons with near-zero-energy. We find a surprising accumulation in the momentum distribution corresponding to meV energy and a \textquotedblleft V"-like structure at the slightly larger transverse momenta. Semiclassical simulations indicate the crucial role of the Coulomb attraction between the escaping electron and the remaining ion at extremely large distance. Tracing back classical trajectories, we find the tunneling electrons born in a certain window of the field phase and transverse velocity are responsible for the striking accumulation. Our theoretical results are consistent with recent meV-resolved high-precision measurements.Comment: 5 pages, 4 figure

Antifungal and anti-inflammatory effects of Coptidis rhizome extract against Candida albicans

Background: Coptidis rhizoma has been used as antibiotics in traditional Chinese medicine practice for many years. Here, we examined the effect of rhizoma Coptidis extract on the growth of C. albicans.Materials and Methods: The antifungal effects of Coptidis rhizoma extract was examined by time-kill assay, transmission electron microscope (TEM) and scanning electron microscope (SEM) observations. The anti-inflammatory effect of the Coptidis rhizoma extract was examined in mouse model of Candida vaginitis.Results: We found that the MIC of Coptidis rhizoma extract was 3.125 mg/mL. The time-kill assay suggested that Coptidis rhizoma extract could inhibit the growth of C. albicans. The SEM and TEM observations showed notable changes of cell wall and cytoplasmic content of the C. albicans and complete collapse of yeast cell exposed to Coptidis rhizoma extract. Our in vivo antifungal activity studies in mouse model of Candidal vaginitis showed the reduction of inflammatory reaction was found after Coptidis rhizoma extract treatment. In addition, the COX-2 expression was decreased in mice treated with Coptidis rhizoma extract as compared with the control mice.Conclusion: Our results indicate that Coptidis rhizoma extract is a promising candidate in candidal vaginitis treatment in the future.Key Words: Antifungal activity, Coptidis rhizoma, C. albican

Fire responses and resistance of concrete-filled steel tubular frame structures

This paper presents the results of dynamic responses and fire resistance of concretefilled steel tubular (CFST) frame structures in fire conditions by using non-linear finite element method. Both strength and stability criteria are considered in the collapse analysis. The frame structures are constructed with circular CFST columns and steel beams of I-sections. In order to validate the finite element solutions, the numerical results are compared with those from a fire resistance test on CFST columns. The finite element model is then adopted to simulate the behaviour of frame structures in fire. The structural responses of the frames, including critical temperature and fire-resisting limit time, are obtained for the ISO-834 standard fire. Parametric studies are carried out to show their influence on the load capacity of the frame structures in fire. Suggestions and recommendations are presented for possible adoption in future construction and design of these structures

Fatigue Crack Growth And Piezoelectric Property Decay Induced By Cyclic Electric Fields For An Actuation Piezoceramic

Degradation of piezoelectric properties of piezomaterials has long been a concern in the applications of actuators and sensors. In this work, alternating electric field induced fatigue crack growth and effect of cyclic electric field on piezoelectric property decay were characterized for a polarized PZT-PIC151. The results show that a relatively high alternating electric field drives the pre-existing microcracks to grow very fast initially due to the superposition of electrostriction induced stress and residual stress at the crack tip, then slow down gradually to becoming dormant. The butterfly loop evolution shows that cyclic electric field strongly degrades the piezoelectric properties due to the frequent domain switching. The output strain decays more than 50% after 106 electric cycles at 0.9 Ec for PIC 151 pellet bonded on an aluminum beam

Robust nodal superconductivity induced by isovalent doping in Ba(Fe1−x_{1-x}Rux_x)2_2As2_2 and BaFe2_2(As1−x_{1-x}Px_x)2_2

We present the ultra-low-temperature heat transport study of iron-based superconductors Ba(Fe$_{1-x}$Ru$_x$)$_2$As$_2$ and BaFe$_2$(As$_{1-x}$P$_x$)$_2$. For optimally doped Ba(Fe$_{0.64}$Ru$_{0.36}$)$_2$As$_2$, a large residual linear term $\kappa_0/T$ at zero field and a $\sqrt{H}$ dependence of $\kappa_0(H)/T$ are observed, which provide strong evidences for nodes in the superconducting gap. This result demonstrates that the isovalent Ru doping can also induce nodal superconductivity, as P does in BaFe$_2$(As$_{0.67}$P$_{0.33}$)$_2$. Furthermore, in underdoped Ba(Fe$_{0.77}$Ru$_{0.23}$)$_2$As$_2$ and heavily underdoped BaFe$_2$(As$_{0.82}$P$_{0.18}$)$_2$, $\kappa_0/T$ manifests similar nodal behavior, which shows the robustness of nodal superconductivity in the underdoped regime and puts constraint on theoretical models.Comment: 5 pages, 4 figures - with two underdoped samples added, this paper supersedes arXiv:1106.541

Extraordinary quasiparticle scattering and bandwidth-control by dopants in iron-based superconductors

The diversities in crystal structures and ways of doping result in extremely diversified phase diagrams for iron-based superconductors. With angle-resolved photoemission spectroscopy (ARPES), we have systematically studied the effects of chemical substitution on the electronic structure of various series of iron-based superconductors. In addition to the control of Fermi surface topology by heterovalent doping, we found two more extraordinary effects of doping: 1. the site and band dependencies of quasiparticle scattering; and more importantly 2. the ubiquitous and significant bandwidth-control by both isovalent and heterovalent dopants in the iron-anion layer. Moreover, we found that the bandwidth-control could be achieved by either applying the chemical pressure or doping electrons, but not by doping holes. Together with other findings provided here, these results complete the microscopic picture of the electronic effects of dopants, which facilitates a unified understanding of the diversified phase diagrams and resolutions to many open issues of various iron-based superconductors.Comment: 12 pages, 9 figure