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Despite a long history of alpine meadows studies, uncertainty remains about the importance of environmental factors in structuring their assembly. We examined the functional and phylogenetic structure of 170 alpine Tibetan meadow communities in relation to elevation, soil moisture and shade. Functional community structure was estimated with both communityweighted mean (CWM) trait values for specific leaf area (SLA), plant height and seed mass and functional diversity (Rao’s quadratic index) for their traits individually and in combination (multivariate functional diversity). We found that shade induced by woody plants significantly increased the phylogenetic diversity and functional diversity of SLA of co-occurring species, suggesting that woody plants behave as “ecosystem engineers” creating a different environment that allows the existence of shade tolerant species and thereby facilitates the coexistence of plant species with different light resource acquisition strategies. We also found evidence for a clear decrease in phylogenetic diversity, CWM and functional diversity related to plant height in the two extreme, both the dry and wet, soil moisture conditions. This indicates that both drought and excess moisture may act as environmental filters selecting species with close phylogenetic relationships and similar height. Moreover, we detected significant decreases in both CWM and functional diversity for seed mass along elevational gradients, suggesting that low net primary productivity (NPP) limits seed size. Finally, because of different individual trait responses to environmental factors, the multivariate functional diversity did not change across environmental gradients. This lack of multivariate response supports the hypothesis that multiple processes, such as environmental filtering, competition and facilitation, may operate simultaneously and exert opposing effects on community assembly along different niche (e.g., water use, light acquisition) axes, resulting in no overall functional community structure change. This contrast between individual and multivariate trait patterns highlights the importance of examining individual traits linked with different ecological processes to better understand the mechanisms of community assembly.

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Two fundamental test systems were used to evaluate the visco-elastic properties of doughs from wheat samples of three varieties grown at four distinct sites. For comparison, tests were also performed with traditional equipment, namely the Mixograph, an extension tester and a Farinograph-type small-scale recording mixer. Uniaxial dough elongation (with an Instron) produced results similar to the conventional extension tester, except that results were provided in fundamental units (Pascals), the critical value recorded being the elongational stress at maximum strain. Stress relaxation measurements were performed following a small initial shear strain. With this method, it was possible to distinguish between the viscosity and the elastic components of dough visco-elasticity. In all the tests the extra dough-strength properties were evident for the variety (Guardian) that had the 5 + 10 glutenin subunits, in contrast to the other two with the 2 + 12 combination of subunits.

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FoxP2 is a member of the winged helix/forkhead class of transcription factors. Despite FoxP2 is found to have particular relevance to speech and language, the role of this gene is broader and not yet fully elucidated. In this study, we investigated the expression of FoxP2 in the brains of bats with different feeding habits (two frugivorous species and three insectivorous species). We found FoxP2 expression in the olfactory tubercle of frugivorous species is significantly higher than that in insectivorous species. Difference of FoxP2 expression was not observed within each of the frugivorous or insectivorous group. The diverse expression patterns in olfactory tubercle between two kinds of bats indicate FoxP2 has a close relation with olfactory tubercle associated functions, suggesting its important role in sensory integration within the olfactory tubercle and such a discrepancy of FoxP2 expression in olfactory tubercle may take responsibility for the different feeding behaviors of frugivorous and insectivorous bats.

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Casein peptides with calcium-chelating capacity were rapidly enriched by using a novel ceramic matrix (CM)-based Ti4+-IMAC adsorbent. The ability of calcium-chelating peptides (CCPs) to bind calcium and the physical properties of complexes formed between CCPs and calcium were investigated. Results demonstrated that the amount of calcium bound depended on the degree of hydrolysis (DH) of casein hydrolysates. The highest calcium binding capacity (683 mg g−1) occurred when bovine casein was hydrolysed by pancreatin at a DH of 0.14%, meanwhile, the calcium content of CCPs-Ca complex exhibited the maximum level (134.96 mg g−1). In addition, CCPs showed a higher radical scavenging capacity (50 µg ml−1; 99% inhibition, or an equivalent activity of 9.91×10−3 M Trolox) compared to casein digest. Moreover, Fourier-transform infrared spectroscopy and fluorescence spectroscopy were used to explore the interaction between CPPs and calcium, and the results demonstrated that phosphoserine residues as well as COO- groups of CCPs were involved in the formation of CCPs-Ca complex.

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Abstract  

The non-isothermal decomposition kinetics of 4Na2SO4·2H2O2·NaCl have been investigated by simultaneous TG-DSC in nitrogen atmosphere and in air. The decomposition processes undergo a single step reaction. The multivariate nonlinear regression technique is used to distinguish kinetic model of 4Na2SO4·2H2O2·NaCl. Results indicate that the reaction type Cn can well describe the decomposition process, the decomposition mechanism is n-dimensional autocatalysis. The kinetic parameters, n, A and E are obtained via multivariate nonlinear regression. The n th-order with autocatalysis model is used to simulate the thermal decomposition of 4Na2SO4·2H2O2·NaCl under isothermal conditions at various temperatures. The flow rate of gas has little effect on the decomposition of 4Na2SO4·2H2O2·NaCl.

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Compound danshen preparations (CDPs) are used clinically for the treatment of cardiovascular and cerebrovascular diseases. By using the quantitative analysis of multi-components by single-marker (QAMS) method, sixteen compounds (danshensu, protocatechuic acid, protocatechuicaldehyde, caffeic acid, rosmarinic acid, lithospermic acid, notoginsenoside R1, salvianolic acid B, ginsenoside Rg1, ginsenoside Re, salvianolic acid A, salvianolic acid C, ginsenoside Rb1, ginsenoside Rd, cryptotanshinone, and tanshinone IIA were quantified on an ACQUITY ultraperformance liquid chromatography (UPLC) HSS T3 column (2.1 × 100 mm, 1.8 μm) with the mobile phase consisting of 0.1% formic acid aqueous solution (A) and acetonitrile (B) using a gradient elution at the flow rate of 0.30 mL/min in 30 min at 30°C, which was also validated by UPLC-diode array detection (DAD) and UPLC-electrospray ionization multistage/mass spectrometry (ESI-MS/MS) for assuring the feasibility and accuracy. Tested by robustness experiment under slightly changeable conditions, the stability of relative correction factor (RCF) proved to be stable, with RSDs below 5.69%, except for notoginsenoside R1 with relative standard deviation (RSD) 7.83%. This reliable and convenient QAMS method resolved the problem of standard substance insufficiency and improved the quality assessment of preparations consisting of complex compounds with different chemical structures, such as CDPs.

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Journal of Thermal Analysis and Calorimetry
Authors: J. Zhi, W. Tian-Fang, L. Shu-Fen, Z. Feng-Qi, L. Zi-Ru, Y. Cui-Mei, L. Yang, L. Shang-Wen, and Z. Gang-Zhui

Abstract  

The effects of aluminum (Al) and nickel (Ni) powders of various grain sizes on the thermal decomposition of ammonium perchlorate (AP) were investigated by TG and DSC in a dynamic nitrogen atmosphere. The TG results show that Al powders have no effect on the thermal decomposition of AP at conventional grain size, while the nanometer-sized Ni powders (n-Ni) have a great influence on the thermal decomposition of AP with conventional and superfine grain size. The results obtained by DSC and an in situ FTIR analysis of the solid residues confirmed the promoting effects of n-Ni. The effects of n-Ni have been ascribed to its enhancement on the gas phase reactions during the second step decomposition of conventional grain size AP.

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To explore the physiological characteristics of the pepc gene in transgenic wheat (Triticum aestivum) plants, PEPC activities in various organs of T3 plants were analyzed at Feekes 6.0, Feekes 10.3 and Feekes 11.1, and compared to control, untransformed wheat cultivar Zhoumai 19. Net photosynthetic rates (P n) in leaves were also measured at the same stages. At Feekes 11.1, both transgenic and control plants were treated with DCDP. Yield traits were surveyed after harvest. The results indicated that P n and PEPC activity in the flag leaf of transgenic wheat were significantly higher than those of the control at different stages. At Feekes 10.3, P n reached the highest value at 28.2 μmol m−2 s−1 and PEPC activity reached the highest value at 104.6 μmol h−1 mg−1. Both factors significantly increased by 21% compared to the control at Feekes 11.1. PEPC activity in the flag leaf of transgenic plants was significantly higher than that of non-leaf organs. P n of transgenic plants was greatly reduced after DCDP treatment. In the flag leaf of transgenic wheat, P n was significantly correlated to PEPC activities at 0.01 probability level with a correlation coefficient of 0.8957**. The yield traits of transgenic line 1-27-3, such as 1000-grain weight, single spike weight and harvest index were higher than those of the control. Additionally, the spike weight of 1-27-3 showed an increase of approximately 9.5% compared to the control. These results indicated that the expression of maize (Zea mays) pepc gene was different across various organs of transgenic wheat and across every growth stage. Therefore, we conclude that introducing maize pepc gene into wheat plants can increase their P n and improve production.

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