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991.
Jingjing Xu David Testa Proshanto K. Mukherjee 《Ocean Development & International Law》2013,44(3):225-240
While shipping is a carbon efficient transport mode, given that roughly 90% of the world trade is carried by ships, the negative impact of shipping on human health and the natural environment is significant. One of the attempts being made by the shipping industry to reduce its environmental impact is to use liquefied natural gas (LNG) as a marine fuel. This article examines the regulatory legal regime in relation to the use of LNG as marine fuel and highlights the areas where further development is necessary. 相似文献
992.
993.
994.
Zhiyuan Yao Gang Wei Haizhen Wang Laosheng Wu Jianjun Wu Jianming Xu 《Applied and environmental microbiology》2013,79(5):1755-1756
Escherichia coli O157:H7 survived longer in soils from plastic-greenhouse cultivation than soils from the open field. Soil pH, organic carbon levels, and the ratio of bacterial phospholipid fatty acids (PLFAs) to fungal PLFAs played the significant roles in survival of O157:H7. Greater attention should be paid to the control of pathogen contamination under conditions of plastic-greenhouse cultivation. 相似文献
995.
Haifeng Lu Jianqing He Zhongwen Wu Wei Xu Hua Zhang Ping Ye Jiezuan Yang Shusen Zhen Lanjuan Li 《Microbial ecology》2013,65(3):781-791
Understanding the composition of the microbial populations in the intestines of liver transplant patients is important to preventing postoperative infection. We investigated the relationship between the risk of postoperative infection and variation in the predominant fecal microbial composition during the perioperative period. We prospectively analyzed the predominant intestinal microbiome of five asymptomatic adult carriers of hepatitis B virus (as controls without any antibiotics) at four weekly follow-up visits and 12 patients before operation and at three weekly postoperative follow-up visits within the first month. Analysis was by denaturing gradient gel electrophoresis (DGGE) and sequencing with digital processing of DGGE profiles using BioNumerics software. Our results showed that the predominant intestinal microbial diversity decreased substantially in eight patients during the perioperative period. Among these, five patients experienced infection with a postoperative hospital stay of more than 30 days. The rest of the four patients who experienced shorter postoperative hospital stays showed only slight variation in predominant intestinal bacterial composition and temporal stability similar to asymptomatic controls. Postoperative fecal DGGE profiles showed mostly bands assigned to Bacteroides and Firmicutes. We conclude that an empiric prophylaxis strategy that destructs gut microecological balance will not be effective in reducing the risk of postoperative infection. Instead, the destruction of intestinal microbiota might result in the appearance of opportunistic pathogens such as Bifidobacterium dentium which rarely appears in the intestinal DGGE profiles of normal humans. Cognizance of the variation of intestinal microbial profiles during the perioperative period is a critical aspect of caring for liver transplant recipients. 相似文献
996.
Yubo Chen Lu Qi Xiaoyu Zhang Jixiang Huang Jibian Wang Hongcheng Chen Xiyuan Ni Fei Xu Yanjun Dong Haiming Xu Jianyi Zhao 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2013,126(10):2499-2509
Increasing seed oil content has become one of the most important breeding criteria in rapeseed (Brassica napus). However, oil content is a complex quantitative trait. QTL mapping in a double haploid population (SG population) emerging from a cross between a German (Sollux) and Chinese (Gaoyou) cultivars revealed one QTL for oil content on linkage group A1 (OilA1), which was mapped to a 17 cM genetic interval. To further validate and characterize the OilA1, we constructed a high-resolution map using B. rapa sequence resources and developed a set of near-isogenic lines (NILs) by employing a DH line SG-DH267 as donor and Chinese parent Gaoyou as recurrent background. The results showed highly conserved synteny order between B. rapa and B. napus within the linkage group A1 and revealed a possible centromere region between two markers ZAASA1-38 and NTP3 (2.5 cM). OilA1 was firstly validated by 250 BC5F2 plants and was confirmed in a 10.6 cM interval between the markers ZAASA1-47 and ZAASA1-77. Further substitution mapping was conducted by using two generations of QTL-NILs, 283 lines from eight BC5F3:4 families and 428 plants from six BC5F4 sub-NILs and thus narrowed the OilA1 interval to 6.9 cM and 4.3 cM (1.4 Mb), respectively. Field investigations with two replications using homozygous BC5F3:4 sister sub-NILs indicated that NILs, which carry a Sollux chromosome segment across the target region showed significant higher oil content (1.26 %, p < 0.001) than their sister NILs containing Gaoyou chromosome. The OilA1 locus is of particular interest for breeding purpose in China because 80 % of Chinese cultivars do not carry this desirable allele. 相似文献
997.
998.
Haitao Li Muhammad Younas Xiaofeng Wang Xuemin Li Lin Chen Bo Zhao Xun Chen Jinsong Xu Fan Hou Baohua Hong Gang Liu Hongyang Zhao Xueli Wu Hongzhi Du Jiangsheng Wu Kede Liu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2013,126(4):937-947
Brassica napus (AACC) is a recent allotetraploid species evolved through hybridization between two diploids, B. rapa (AA) and B. oleracea (CC). Due to extensive genome duplication and homoeology within and between the A and C genomes of B. napus, most SSR markers display multiple fragments or loci, which limit their application in genetics and breeding studies of this economically important crop. In this study, we collected 3,890 SSR markers from previous studies and also developed 5,968 SSR markers from genomic sequences of B. rapa, B. oleracea and B. napus. Of these, 2,701 markers that produced single amplicons were putative single-locus markers in the B. napus genome. Finally, a set of 230 high-quality single-locus SSR markers were established and assigned to the 19 linkage groups of B. napus using a segregating population with 154 DH individuals. A subset of 78 selected single-locus SSR markers was proved to be highly stable and could successfully discriminate each of the 45 inbred lines and hybrids. In addition, most of the 230 SSR markers showed the single-locus nature in at least one of the Brassica species of the U’s triangle besides B. napus. These results indicated that this set of single-locus SSR markers has a wide range of coverage with excellent stability and would be useful for gene tagging, sequence scaffold assignment, comparative mapping, diversity analysis, variety identification and association mapping in Brassica species. 相似文献
999.
1000.
Yan Geng Zhe He Zhen-Ming Lu Hong-Yu Xu Guo-Hua Xu Jin-Song Shi Zheng-Hong Xu 《Applied microbiology and biotechnology》2013,97(7):2851-2858
Antrodia camphorata is a well-known Chinese medicinal mushroom that protects against diverse health-related conditions. Submerged fermentation of A. camphorata is an alternative choice for the effective production of bioactive metabolites, but the effects of nutrition and environment on mycelial morphology are largely unknown. In this study, we show that A. camphorata American Type Culture Collection 200183 can form arthrospores in the end of liquid fermentation. Different morphologies of A. camphorata in submerged culture were analyzed using scanning electron microscopy. The optimal carbon and nitrogen sources for sporulation were soluble starch and yeast extract. We found that a carbon-to-nitrogen ratio (C/N) of 40:1, MgSO4 (0.5 g/l), KH2PO4 (3.0 g/l), an initial pH?5.0, and an inoculum size of 1.5?×?105 spores/ml led to maximum production of arthroconidia. Our results will be useful in the regulation and optimization of A. camphorata cultures for efficient production of arthroconidia in submerged culture, which can be used as inocula in subsequent fermentation processes. 相似文献