9,023 research outputs found
Review on the different method of dating mafic-ultramafic rocks in the orogenic belt - taking the Shunchang massif as an example
Based on the analysis of different dating methods of isotopic system and the dating results of the metamorphic mafic-ultramafic rocks in Shunchang, Northern Fujian, it s proposed in the paper that the U-Pb method of single zircon and the method of the whole-rock Sm-Nd isochronic age should be taken as the main ways for dating metamorphic mafic-ultramafic rocks in the orogenic belts. The discovery of younger ages dating with the Rb-Sr, 40Ar-39Ar and K-Ar methods suggests that caution is warranted in using these isotopic systems to date metamorphic mafic-ultramafic rocks.通过对不同同位素体系测年方法的分析, 并结合闽北顺昌镁铁 - 超镁铁杂岩的系统同位素年代测定结果, 提出造山带中变质镁铁 - 超镁铁岩的年代测定应以颗粒铅石U-Pb 法和全岩Sm-Nd 等时线法为主, 对Rb-Sr 、40Ar-39Ar 和K-Ar 同位素测年结果的应用应持慎重态度。published_or_final_versio
Profiling real-time aroma from green tea infusion during brewing
Aroma substances are the most crucial criteria for the sensory evaluation of tea quality, and also key attractors influencing consumers to make the decision for purchasing tea. Understanding the aromatic properties of tea infusion during different brewing time is crucial to control the tea aromatic quality. Here, headspace and direct immersion solid-phase microextraction (HS-SPME and DI-SPME), coupled with GC-MS, were employed to investigate the impact of brewing time on the changes of the volatile features of green tea infusion. Esters, aldehydes, alcohols, fatty acids, and alkaloids were the predominant volatile groups from tea infusions. Two to three minutes was identified as the best duration for the tea brewing that can maximize the abundance of aromatic chemicals in the headspace emitted from the tea infusions. The variation of the key aromatic contributors between the tea infusion and the headspace over the infusion tended to equilibrate during the tea brewing process. This study provides a theory-based reference method by analyzing the real-time aromatic characteristics in green tea. The optimal time was determined for aromatic quality control, and the complementary relationship between the volatiles in the headspace and its counterpart, tea infusion, was primarily elucidated
Depth enhancement of optical scanning holography with a spiral phase plate
Poster Session (DW2A): no. DW2A.3A spiral phase plate is applied to the optical scanning holography system to improve the depth resolution of the reconstruction, the simulation results show that the depth interval can be resolved at a 0.4 mm with only a single hologram. © 2015 OSApostprin
Allelic variation of low molecular weight glutenin subunits composition and the revealed genetic diversity in durum wheat Triticum turgidum L. ssp. durum
Low molecular weight glutenin subunits (LMW-GS) play an important role in determining the bread-making characteristics of dough in the end-use quality of wheat. In this study, A total of 149 worldwide-originated durum wheat were used to analyze the composition of LMW-GS using MALDI-TOF-MS. Based on the allelic variation of glutenin subunits, the genetic diversity was evaluated for the 149 durum wheat. Five types of alleles were identified at the Glu-A3 locus with Glu-A3e, Glu-A3a/c, Glu-A3f, Glu-A3d and Glu-A3b accounting for 43.0%, 16.1%, 12.8%, 10.1% and 7.4 % of the accessions, respectively. Five types of alleles were identified at the Glu-B3 locus: Glu-B3d (60.4%), Glu-B3b (6.0%), Glu-B3c (6.0%), Glu-B3h (2.7%) and Glu-B3f (0.7%). Two novel alleles encoding abnormal subunits 40500 Da and 41260 Da were identified at the Glu-A3 and Glu-B3 loci, respectively. Further studies are needed to match these novel alleles to previously discovered novel alleles. Moreover, the genetic diversity analysis indicated that great genetic variation existed in durum wheat among encoding loci of glutenin subunits, released periods of varieties and different geographical origins. The results provide more important information of potential germplasm for the improvement of durum wheat and common wheat
Controlled release of recombinant human cementum protein 1 from electrospun multiphasic scaffold for cementum regeneration
Periodontitis is a major cause for tooth loss, which affects about 15% of the adult population. Cementum regeneration has been the crux of constructing the periodontal complex. Cementum protein 1 (CEMP1) is a cementum-specific protein that can induce cementogenic differentiation. In this study, poly(ethylene glycol) (PEG)-tabilized amorphous calcium phosphate (ACP) nanoparticles were prepared by wet-chemical method and then loaded with recombinant human CEMP1 (rhCEMPl) for controlled release. An electrospun multiphasic scaffold constituted of poly(ε-caprolactone) (PCL), type I collagen (COL), and rhCEMPl/ACP was fabricated. The effects of rhCEMPl/ACP/PCL/COL scaffold on the attachment proliferation, osteogenic, and cementogenic differentiations of human periodontal ligament cells, (PDLCs) were systematically investigated. A critical size defect rat model was introduced to evaluate the effect of tissue regeneration of the scaffolds in vivo. The results showed that PEG-stabilized ACP nanoparticles formed a core-shell structure with sustained release of rhCEMP1 for up to 4 weeks. rhCEMPl/ACP/PCL/COL scaffold could suppress PDLCs proliferation behavior and upregulate the expression of cementoblastic markers including CEMP1 and cementum attachment protein while downregulating osteoblastic markers including osteocalcin and osteopontin when it was cocultured with PDLCs in vitro for 7 days. Histology analysis of cementum after being implanted with the scaffold in rats for 8 weeks showed that there was cementum-like tissue formation but little bone formation. These results indicated the potential of using electrospun multiphasic scaffolds for controlled release of rhCEMP1 for promoting cementum regeneration in reconstruction of the periodontal complex
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
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