[Application of micro-computed tomography (µCT)in quantifying xylem vessels of broadleaved trees]. / 计算机显微断层扫描技术(µCT)åœ¨é‡åŒ–é˜”å¶æ ‘ç§å¯¼ç®¡ä¸­çš„åº”ç”¨.

Quantitative analysis of vessel characteristics at the cellular scale is of great significance for understan-ding plant adaptation strategies to environment. The direct grinding combined with stereo-microscope imaging is one of the main approaches to examine the anatomical structure of xylem (conifer tracheid and hardwood vessel) wood structure, which inevitably damages xylem cells, hindering the accurate understanding of anatomical structures. In this study, we applied X-ray micro-computed tomography (µCT) and stereo-microscope technology to quantitatively measure the diameter and area of vessels of seven Canadian broadleaved tree species (Acer saccharum, Betula papyrifera, Fraxinus americana, Ostrya virginiana, Populus grandidentata, Quercus rubra, and Carya cordiformis). We fitted the results by linear model and tested the feasibility of µCT technology in quantifying the vessel size of broadleaved species. We found that the results of the two methods for measuring vessel size were highly similar (R2=0.98). The goodness of fit of the vessel diameter results measured by the two methods for the ring-porous wood species (C. cordiformis, R2=0.98; F. americana, R2=0.96; Q. rubra, R2=0.99) was higher than that of the diffuse-porous wood species (B. papyrifera, R2=0.88; O. virginiana, R2=0.73; A. saccharum, R2=0.68; P. grandiden-tata, R2=0.88). The goodness of fit of small vessels (diameter≤200 µm, R2=0.94) measured by the two methods was higher than that of large vessels (diameter>200 µm, R2=0.92). Thus, the µCT technique provided a new non-destructive detection method for quantifying xylem vessels of broadleaved tree species.

[Microbial Community Diversity Analysis During Composting of Lincomycin Mycelia Dreg with Manure].

Aerobic composting experiments were conducted using lincomycin mycelia wastes (dreg) and manure (T), using sewage sludge with manure as a control (CK). High performance liquid phase methods and high throughput sequencing were used to determine the concentration of lincomycin residue and to characterize the microbial community. The results showed that lincomycin was reduced significantly, with the concentration decreasing from 1800 mg·kg-1 to 483 mg·kg-1, accounting for 73% degradation. In addition, the bacterial community abundance and diversity indices were all lower than that of sludge-manure at the mesophilic and thermophilic phases, because of the high concentration of lincomycin residue in lincomycin mycelia dreg. By contrast, the fungal community abundance and diversity indices showed the reverse, due to the high content of organic matter and nitrogen in lincomycin mycelia dreg. Therefore, the microbial communities were greatly different between T and CK treatment with the domain genera of Paucisalibacillus, Cerasibacillus, Bacillus, Virgibacillus, Ureibacillus, Paenibacillus, and Sinibacillus in T compost and Truepera, Actinomadura, Pseudosphingobacterium, Pseudomonas, Luteimonas and Ureibacillus in CK compost. However, as the composting continued to a mature phase, most of the lincomycin was reduced, and the differences between the two microbial communities gradually decreased. This showed that composting could make lincomycin mycelia dreg harmless and could be used to turn it into a resource.

Fast Differential Analysis of Propolis Using Surface Desorption Atmospheric Pressure Chemical Ionization Mass Spectrometry.

Mass spectral fingerprints of 24 raw propolis samples, including 23 from China and one from the United States, were directly obtained using surface desorption atmospheric pressure chemical ionization mass spectrometry (SDAPCI-MS) without sample pretreatment. Under the optimized experimental conditions, the most abundant signals were detected in the mass ranges of 70 to 500 m/z and 200 to 350 m/z, respectively. Principal component analyses (PCA) for the two mass ranges showed similarities in that the colors had a significant correlation with the first two PCs; in contrast there was no correlation with the climatic zones from which the samples originated. Analytes such as chrysin, pinocembrin, and quercetin were detected and identified using multiple stage mass spectrometry within 3 min. Therefore, SDAPCI-MS can be used for rapid and reliable high-throughput analysis of propolis.

[Infrared Spectrum Analysis of Propolis and Tree Gum Collected from Different Areas].

Propolis possesses functions of antibacterial, antiviral, anticancer, and liver protection, and is known as the "purple gold", however, the phenomenon which making and selling of counterfeit are growing in intensity. In order to establish a authenticity and quality of propolis evaluation model, in this paper, forty-one Chinese propolis, one proplis from United States and two tree gums were used for experimental materials. The infrared spectrum collection was performed by Fourier transform infrared spectrometer, and principal component analysis (PCA) was used for data analysis. The result showed that, the intrared spectrum of propolis and tree gum were significantly different. The propolis characteristic peak only appeared in 2500-3500 and 400-1800 cm⁻¹. All propolis had two frequency region of characteristic peaks, 2849.08-2848.53 and 2917.74- 2916.76 cm⁻¹, but tree gum did not have characteristic peak in this region. The characteristic peaks of gum were in 1150-1300 and 1550-1650 cm⁻¹. Differences in these aspects can be used to distinguish propolis and gum, and can be used to identify true and false propolis. We use Qinghai propolis as a standard sample, in 42 samples, the matching degree of other propolis is > 80%. In addition, the result of PCA shows that tree gum and the propolis from different climate zone, or with different colors could be distinguished well. This paper firstly performed analysis on different propolis and gum by infrared spectrum, and a new method, for authenticity and quality of propolis identification, could be developed.

The evolution of Anammox performance and granular sludge characteristics under the stress of phenol.

The short- and long-term effects of phenol on anaerobic ammonium oxidation (Anammox) were evaluated. The short-term impact of phenol on Anammox activity was determined by a batch test, and an IC50 value of 678.2 mg L(-1) was calculated. Anammox granular sludge was equally seeded into two identical upflow anaerobic sludge blanket reactors (R0 and R1); synthetic wastewater without phenol was fed to R0 while with varied phenol was fed to R1 to study the long-term effects. The performance of R0 was stable, with a steadily rising nitrogen removal rate of 10.5-21.3 kg N m(-3)d ay(-1). However, the performance of R1 was significantly suppressed by an influent phenol concentration of 50 mg L(-1), and was recovered and stabilized by applying one or more control strategies. The phenol-mediated inhibition depressed the Anammox activity and biomass, and caused a change of stoichiometric ratios and granule characteristics.