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21.
This study dealt with a restoration project conducted at South‐East New Territories Landfill in Hong Kong, in order to screen suitable tree and shrub species (both native and pioneer species) for revegetation. For engineered landfills, landfill gas migration and leachate contamination to the topsoil are rarely problematic, but the lack of nutrients and moisture and poor physical soil conditions may jeopardize potential woodland establishment. The growth performance of 25 woody plant species subjected to 12 different soil amelioration and seedlings planting methods was compared. The results showed that the general performance (mortality rate, apical height, crown diameter and basal diameter) of pioneer species (notably Acacia species) was much better than that of native species in all blocks of woodland mix and scrub mix. The notch planting method was effective in helping seedling roots to have better contact with soil for water uptake, which subsequently increased the survival rates of seedlings, leading to a better tree coverage. Soil ameliorations (horticultural soil with fertilizer and horse and pig manure) generally increased the seedling survival rate and improved plant growth. Tree coverage on all the plant trial blocks was mainly established by the three Acacia species. A planting distance of 1 m was recommended for woodland establishment, and such dense seedlings planting would achieve a better tree coverage under a shorter period of time (than the distance of 3 m). Difficulties in woodland establishment were discussed, and the strategies for achieving a better tree growth were recommended. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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Journal of Crop Science and Biotechnology - Fatty acids (FAs) are important desirable compounds in oil crops. Here, we evaluated the amounts of 14 FAs in sesame grains using gas chromatography mass...  相似文献   
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We describe the efficacy of L-870812, an inhibitor of HIV-1 and SIV integrase, in rhesus macaques infected with the simian-human immunodeficiency virus (SHIV) 89.6P. When initiated before CD4 cell depletion, L-870812 therapy mediated a sustained suppression of viremia, preserving CD4 levels and permitting the induction of virus-specific cellular immunity. L-870812 was also active in chronic infection; however, the magnitude and durability of the effect varied in conjunction with the pretreatment immune response and viral load. These studies demonstrate integrase inhibitor activity in vivo and suggest that cellular immunity facilitates chemotherapeutic efficacy in retroviral infections.  相似文献   
25.
Lam PY  Yan CW  Chiu PY  Leung HY  Ko KM 《Fitoterapia》2011,82(3):393-400
Schisandrin B (Sch B) and schisandrin C (Sch C), but not schisandrin A and dimethyl diphenyl bicarboxylate, protected rat skin tissue against solar irradiation-induced oxidative injury, as evidenced by a reversal of solar irradiation-induced changes in cellular reduced glutathione and α-tocopherol levels, as well as antioxidant enzyme activities and malondialdehyde production. The cytochrome P-450-mediated metabolism of Sch B or Sch C caused ROS production in rat skin microsomes. Taken together, Sch B or Sch C, by virtue of its pro-oxidant action and the subsequent eliciting of a glutathione antioxidant response, may prevent photo-aging of skin.  相似文献   
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Polycyclic aromatic hydrocarbons (PAHs) are considered to be atmospheric pollutants and well-known human carcinogens. This study analyzes the pollution scenarios of PAHs in the aerosol of Higashi Hiroshima, Japan. We examined the characteristics, the influences of meteorological conditions, the distribution and seasonal variation of PAHs in aerosol samples collected from June 2000 to May 2001. The concentration of PAHs in the aerosol of Higashi Hiroshima was ranging from 11.8 to 157.5 μg/g with a mean concentration of 63.4 μg/g. Results showed that there is positive correlation between aerosol PAH concentrations and ambient temperature but a relatively little correlation with solar radiation. Seasonal variation was observed with a higher concentration during winter and lower concentration during summer. Apart from that, principal component analysis and molecular diagnostic ratios were also used to characterize and identify possible PAHs emission sources. Results obtained strongly suggested that vehicular emissions appeared to be the major source of aerosol PAHs in this study although other sources do have some degree of influence.  相似文献   
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We conducted a screening campaign to investigate fungi as a source for new antimalarial compounds. A subset of our fungal collection comprising Chinese mangrove endophytes provided over 5000 lipophilic extracts. We developed an accelerated discovery program based on small-scale cultivation for crude extract screening and a high-throughput malaria assay. Criteria for hits were developed and high priority hits were subjected to scale-up cultivation. Extracts from large scale cultivation were fractionated and these fractions subjected to both in vitro malaria and cytotoxicity screening. Criteria for advancing fractions to purification were developed, including the introduction of a selectivity index and by dereplication of known metabolites. From the Chinese mangrove endophytes, four new compounds (14–16, 18) were isolated including a new dimeric tetrahydroxanthone, dicerandrol D (14), which was found to display the most favorable bioactivity profile.  相似文献   
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Journal of General Plant Pathology - An easy, rapid method has been needed to test the pathogenicity of strains of Ralstonia pseudosolanacearum, the cause of serious bacterial wilt on ginger...  相似文献   
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Significant dust storm impacts have seldom been recorded and reported in Hong Kong. Herein, four cases which occurred in Hong Kong during the spring times of recent years are examined using back-trajectory computation and chemical analysis of air-borne samples. All of the cases show that the dust was transported from the source to Hong Kong in 2–5 days and that PM10 concentrations approached or exceeded the European Union air quality criteria and the USA National Ambient Air Quality Standard. The chemical characteristics of the samples taken in these events agreed both with those from the source regions and with those archived from selected Hong Kong datasets. The concentrations of the crustal constituents (Al, Fe, Mn, Ca) of the Hong Kong samples on the episode days were at least three times higher than the concentrations measured on non-episode days. The mass ratios of Fe/Al and Mn/Al (but not Ca/Al) can act as good tracers of Asian dust storms to this coastal site where sea-salt and other anthropogenic species are normally dominant. Furthermore, unusually high Mg levels indicated a mainly crustal origin for this element, rather than the marine origin normally found at this coastal location. Particulate nitrate exhibited more elevated concentrations in all of the dust storm samples than in non-dust-storm and local samples.  相似文献   
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