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991.
Lanping Li Zhikuo Li Marc W. Cadotte Peng Jia Guanguang Chen Lanna S. Jin Guozhen Du 《Oecologia》2016,182(2):419-428
The study of phylogenetic conservatism in alpine plant phenology is critical for predicting climate change impacts; currently we have a poor understanding of how phylogeny and climate factors interactively influence plant phenology. Therefore, we explored the influence of phylogeny and climate factors on flowering phenology in alpine meadows. For two different types of alpine plant communities, we recorded phenological data, including flowering peak, first flower budding, first flowering, first fruiting and the flowering end for 62 species over the course of 5 years (2008–2012). From sequences in two plastid regions, we constructed phylogenetic trees. We used Blomberg’s K and Pagel’s lambda to assess the phylogenetic signal in phenological traits and species’ phenological responses to climate factors. We found a significant phylogenetic signal in the date of all reproductive phenological events and in species’ phenological responses to weekly day length and temperature. The number of species in flower was strongly associated with the weekly day lengths and followed by the weekly temperature prior to phenological activity. Based on phylogenetic eigenvector regression (PVR) analysis, we found a highly shared influence of phylogeny and climate factors on alpine species flowering phenology. Our results suggest the phylogenetic conservatism in both flowering and fruiting phenology may depend on the similarity of responses to external environmental cues among close relatives. 相似文献
992.
枇杷种子不耐贮藏,属于脱水敏感的种子。在干燥脱水过程中,子叶和胚轴的超氧物歧化酶(SOD) 和过氧化物酶(POD) 活性不断下降,而丙二醛( MDA) 含量及种子浸泡液的电导率不断增加,种子活力逐渐降低。外源0 .05 ~0 .25 mmol/L 的抗坏血酸(ASA) ,0 .05 ~5 .0 mmol/L 的还原性谷胱甘肽(GSH)和0 .05 ~0 .5 mmol/L 的Ca2 + 处理能有效地增强种胚防御过氧化的能力,缓解氧自由基对种胚的伤害,提高脱水劣变的种子活力。 相似文献
993.
994.
Jin-jing Wang Wei-na Xu Xin’er Li Jia Li Qi Li 《World journal of microbiology & biotechnology》2014,30(6):1901-1908
The flavor stability during storage is very important to the freshness and shelf life of beer. However, beer fermented with a yeast strain which is prone to autolyze will significantly affect the flavor of product. In this study, the gene encoding β-1,3-glucan synthetase catalytic subunit (fks1) of the lager yeast was destroyed via self-clone strategy. β-1,3-glucan is the principle cell wall component, so fks1 disruption caused a decrease in β-1,3-glucan level and increase in chitin level in cell wall, resulting in the increased cell wall thickness. Comparing with wild-type strain, the mutant strain had 39.9 and 63.41 % less leakage of octanoic acid and decanoic acid which would significantly affect the flavor of beer during storage. Moreover, the results of European Brewery Convention tube fermentation test showed that the genetic manipulation to the industrial brewing yeast helped with the anti-staling ability, rather than affecting the fermentation ability. The thiobarbituric acid value reduced by 65.59 %, and the resistant staling value increased by 26.56 %. Moreover, the anti-staling index of the beer fermented with mutant strain increased by 2.64-fold than that from wild-type strain respectively. China has the most production and consumption of beer around the world, so the quality of beer has a significant impact on Chinese beer industry. The result of this study could help with the improvement of the quality of beer in China as well as around the world. 相似文献
995.
Li-Jun Jia Shou-Fa Zhang Nian-Chao Qian Xue-Nan Xuan Long-Zheng Yu Xue-Mei Zhang Ming-Ming Liu 《The Korean journal of parasitology》2013,51(2):247-253
Neospora caninum is the etiologic agent of bovine neosporosis, which affects the reproductive performance of cattle worldwide. The transmembrane protein, NcSRS2, and dense-granule protein, NcGRA7, were identified as protective antigens based on their ability to induce significant protective immune responses in murine neosporosis models. In the current study, NcSRS2 and NcGRA7 genes were spliced by overlap-extension PCR in a recombinant adenovirus termed Ad5-NcSRS2-NcGRA 7, expressing the NcSRS2-NcGRA7 gene, and the efficacy was evaluated in mice. The results showed that the titer of the recombinant adenovirus was 109TCID50/ml. Three weeks post-boost immunization (w.p.b.i.), the IgG antibody titer in sera was as high as 1:4,096. IFN-γ and IL-4 levels were significantly different from the control group (P<0.01). This research established a solid foundation for the development of a recombinant adenovirus vaccine against bovine N. caninum. 相似文献
996.
Yajing He Zhaowei Meng Qiang Jia Fang Hu Xianghui He Jian Tan Guizhi Zhang Xue Li Jianping Zhang Qing Zhang Li Liu Lili Zhao Jing Li Yuling Wang Yumei Qian Shuling Hou Hua Liu Sheng Wang Renfei Wang Wei Zheng Tianpeng Hu Na Liu Arun Upadhyaya Yang Liu 《PloS one》2015,10(6)
Objective
We aimed to measure prevalence of sleep disturbance in patients with differentiated thyroid cancer (DTC) by calculating Pittsburgh Sleep Quality Index (PSQI), and compare these data with patients with benign thyroid nodules or normal participants.Methods
Three groups of patients participated in this cross-sectional study. In the first group, 162 patients with DTC received total thyroidectomy, and then 131I therapy. The second group consisted of 84 patients with benign thyroid nodules, who received partial thyroidectomy. The third group was 78 normal healthy control cases. PSQI was used to assess the sleep quality. Inter-group differences were analyzed by Kruskal-Wallis test or independent samples T test. χ2 test was also used to check prevalence differences of poor sleep quality among the groups. Differences of PSQI score and poor sleep quality prevalence before and after 131I therapy in the same group of DTC participants were analyzed by paired T test and Mcnemar''s test.Results
Higher PSQI score (7.59 ± 4.21) and higher rate of poor sleep quality (54.32%) were shown in DTC patients than in any other group. After 131I therapy, PSQI score and prevalence of poor sleep quality in DTC patients increased significantly to 8.78 ± 4.72 and 70.99%. Then DTC patients were divided into two subgroups based on their metastatic status. DTC patients with metastasis (87/162 cases, 53.70%) had significantly higher PSQI score (10.87 ± 5.18) and higher prevalence of poor sleep quality (79.31%).Conclusion
DTC patients suffer from sleep disturbance, 131I therapy and awareness of metastatic status could worsen sleep problem. Psychological fear of cancer, nuclear medicine therapy and metastasis could be one major underlying reason. Longitude and interventional studies are necessary for further investigations. 相似文献997.
Five different crystals have been obtained for the first time from the aerial parts of Limonium aureum (L.)Hill ex kuntze. They were identified as follows: (Ⅰ) homoeriodictyol, (Ⅱ) naringenin, (Ⅲ) eriodictyol (Ⅳ) myricetin-3-O-β-D-glucoside and (Ⅴ) myricetin-3-O-β-D-galactoside. 相似文献
998.
999.
Microbial community analysis of an aerobic nitrifying-denitrifying MBR treating ABS resin wastewater 总被引:1,自引:0,他引:1
A two-stage aerobic membrane bioreactor (MBR) system for treating acrylonitrile butadiene styrene (ABS) resin wastewater was carried out in this study to evaluate the system performance on nitrification. The results showed that nitrification of the aerobic MBR system was significant and the highest TKN removal of approximately 90% was obtained at hydraulic retention time (HRT) 18 h. In addition, the result of nitrogen mass balance revealed that the percentage of TN removal due to denitrification was in the range of 8.7-19.8%. Microbial community analysis based on 16s rDNA molecular approach indicated that the dominant ammonia oxidizing bacteria (AOB) group in the system was a β-class ammonia oxidizer which was identified as uncultured sludge bacterium (AF234732). A heterotrophic aerobic denitrifier identified as Thauera mechernichensis was found in the system. The results indicated that a sole aerobic MBR system for simultaneous removals of carbon and nitrogen can be designed and operated for neglect with an anaerobic unit. 相似文献