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131.
132.
Biodiversity and ecosystem services: lessons from nature to improve management of planted forests for REDD-plus 总被引:1,自引:0,他引:1
Ian D. Thompson Kimiko Okabe John A. Parrotta Eckehard Brockerhoff Hervé Jactel David I. Forrester Hisatomo Taki 《Biodiversity and Conservation》2014,23(10):2613-2635
Planted forests are increasingly contributing wood products and other ecosystem services at a global scale. These forests will be even more important as carbon markets develop and REDD-plus forest programs (forests used specifically to reduce atmospheric emissions of CO2 through deforestation and forest degradation) become common. Restoring degraded and deforested areas with long-rotation planted forests can be accomplished in a manner that enhances carbon storage and other key ecosystem services. Knowledge from natural systems and understanding the functioning novel of ecosystems can be instructive for planning and restoring future forests. Here we summarize information pertaining to the mechanisms by which biodiversity functions to provide ecosystem services including: production, pest control, pollination, resilience, nutrient cycling, seed dispersal, and water quality and quantity and suggest options to improve planted forest management, especially for REDD-plus. 相似文献
133.
Unmanned Aerial Survey of Fallen Trees in a Deciduous Broadleaved Forest in Eastern Japan 总被引:1,自引:0,他引:1
Tomoharu Inoue Shin Nagai Satoshi Yamashita Hadi Fadaei Reiichiro Ishii Kimiko Okabe Hisatomo Taki Yoshiaki Honda Koji Kajiwara Rikie Suzuki 《PloS one》2014,9(10)
Since fallen trees are a key factor in biodiversity and biogeochemical cycling, information about their spatial distribution is of use in determining species distribution and nutrient and carbon cycling in forest ecosystems. Ground-based surveys are both time consuming and labour intensive. Remote-sensing technology can reduce these costs. Here, we used high-spatial-resolution aerial photographs (0.5–1.0 cm per pixel) taken from an unmanned aerial vehicle (UAV) to survey fallen trees in a deciduous broadleaved forest in eastern Japan. In nine sub-plots we found a total of 44 fallen trees by ground survey. From the aerial photographs, we identified 80% to 90% of fallen trees that were >30 cm in diameter or >10 m in length, but missed many that were narrower or shorter. This failure may be due to the similarity of fallen trees to trunks and branches of standing trees or masking by standing trees. Views of the same point from different angles may improve the detection rate because they would provide more opportunity to detect fallen trees hidden by standing trees. Our results suggest that UAV surveys will make it possible to monitor the spatial and temporal variations in forest structure and function at lower cost. 相似文献
134.
In vitro inhibitory effects of Daphne oleoides ssp. oleoides on inflammatory cytokines and activity-guided isolation of active constituents 总被引:4,自引:0,他引:4
Yeşilada E Taninaka H Takaishi Y Honda G Sezik E Momota H Ohmoto Y Taki T 《Cytokine》2001,13(6):359-364
Aerial parts of Daphne oleoides Schreber ssp. oleoides (Thymelaeaceae) are used to treat rheumatoid arthritis and lumbago in Turkish folk medicine. In order to evaluate folkloric utilization, in vitro inhibitory effects of the ethyl acetate extract and fractions obtained from this extract on interleukin 1 (IL-1alpha, IL-1beta) and tumour necrosis factor (TNF-alpha) biosynthesis were studied. Through chemical isolation techniques and activity-guided fractionation process, seventeen compounds were isolated and their structures were elucidated (numbered 1-17). Diterpenoids genkwadaphnin (3) and 1,2-dehydrodaphnetoxin (6) and a coumarin derivative daphnetin (9) showed potent inhibitory activity and were found to be the main active ingredients. Furthermore, gnidilatin (4), gnidilatin-20 palmitate (5), genkwadaphnin-20-palmitate (7) and gnidicin-20-palmitate (8), having diterpenoid structure, and eudesmine (12), wikstromol (13) and matairesinol (14), having lignan structure, were determined to possess moderate inhibitory activity and may have a contributory role in the effect of the remedy. 相似文献
135.
Nouchi R Taki Y Takeuchi H Hashizume H Akitsuki Y Shigemune Y Sekiguchi A Kotozaki Y Tsukiura T Yomogida Y Kawashima R 《PloS one》2012,7(1):e29676
Background
The beneficial effects of brain training games are expected to transfer to other cognitive functions, but these beneficial effects are poorly understood. Here we investigate the impact of the brain training game (Brain Age) on cognitive functions in the elderly.Methods and Results
Thirty-two elderly volunteers were recruited through an advertisement in the local newspaper and randomly assigned to either of two game groups (Brain Age, Tetris). This study was completed by 14 of the 16 members in the Brain Age group and 14 of the 16 members in the Tetris group. To maximize the benefit of the interventions, all participants were non-gamers who reported playing less than one hour of video games per week over the past 2 years. Participants in both the Brain Age and the Tetris groups played their game for about 15 minutes per day, at least 5 days per week, for 4 weeks. Each group played for a total of about 20 days. Measures of the cognitive functions were conducted before and after training. Measures of the cognitive functions fell into four categories (global cognitive status, executive functions, attention, and processing speed). Results showed that the effects of the brain training game were transferred to executive functions and to processing speed. However, the brain training game showed no transfer effect on any global cognitive status nor attention.Conclusions
Our results showed that playing Brain Age for 4 weeks could lead to improve cognitive functions (executive functions and processing speed) in the elderly. This result indicated that there is a possibility which the elderly could improve executive functions and processing speed in short term training. The results need replication in large samples. Long-term effects and relevance for every-day functioning remain uncertain as yet.Trial Registration
UMIN Clinical Trial Registry 000002825 相似文献136.
137.
Badria B El Sayed Colin A Malcolm Ahmed Babiker Elfatih M Malik Mohammed AH El Tayeb Nageeb S Saeed Abdel Hameed D Nugud Bart GJ Knols 《Malaria journal》2009,8(Z2):S3
The global malaria situation, especially in Africa, and the problems frequently encountered in chemical control of vectors such as insecticide resistance, emphasize the urgency of research, development and implementation of new vector control technologies that are applicable at regional and local levels. The successful application of the sterile insect technique (SIT) for the control of the New World screwworm Cochliomyia hominivorax and several species of fruit flies has given impetus to the use of this method for suppression or elimination of malaria vectors in some areas of Africa including Northern State of Sudan. The research and development phase of the Northern State feasibility study has been started. Sudanese stakeholders are working side-by-side with the International Atomic Energy Agency in the activities of this important phase. Several ethical, legal and social issues associated with this approach arose during this phase of the project. They need to be seriously considered and handled with care. In this paper, these issues are described, and the current and proposed activities to overcome potential hurdles to ensure success of the project are listed. 相似文献
138.
Peng X Taki H Komukai S Sekine M Kanoh K Kasai H Choi SK Omata S Tanikawa S Harayama S Misawa N 《Applied microbiology and biotechnology》2006,71(6):824-832
Four genes were isolated and characterized for alcohol dehydrogenases (ADHs) catalyzing the oxidation of aromatic alcohols such as benzyl alcohol to their corresponding aldehydes, one from o-xylene-degrading Rhodococcus
opacus TKN14 and the other three from n-alkane-degrading Rhodococcus
erythropolis PR4. Various aromatic alcohols were bioconverted to their corresponding carboxylic acids using Escherichia
coli cells expressing each of the four ADH genes together with an aromatic aldehyde dehydrogenase gene (phnN) from Sphingomonas sp. strain 14DN61. The ADH gene (designated adhA) from strain TKN14 had the ability to biotransform a wide variety of aromatic alcohols, i.e., 2-hydroxymethyl-6-methylnaphthalene, 2-hydroxymethylnaphthalene, xylene-α,α’-diol, 3-chlorobenzyl alcohol, and vanillyl alcohol, in addition to benzyl alcohol with or without a hydroxyl, methyl, or methoxy substitution. In contrast, the three ADH genes of strain PR4 (designated adhA, adhB, and adhC) exhibited lower ability to degrade these alcohols: these genes stimulated the conversion of the alcohol substrates by only threefold or less of the control value. One exception was the conversion of 3-methoxybenzyl alcohol, which was stimulated sevenfold by adhB. A phylogenetic analysis of the amino acid sequences of these four enzymes indicated that they differed from other Zn-dependent ADHs.The first two authors contributed equally to this work 相似文献
139.
Horizontal and vertical distribution and demography of euphausiids in the Ross Sea and its adjacent waters in 2004/2005 总被引:1,自引:0,他引:1
Kenji Taki Takashi Yabuki Yoshifumi Noiri Tomonari Hayashi Mikio Naganobu 《Polar Biology》2008,31(11):1343-1356
The horizontal and vertical distribution and population structure of euphausiids in the Ross Sea and its adjacent waters were
investigated during the summers of 2004/2005 using stratified towed samples. Nine species of euphausiids occurred in the survey
area. Among them, Euphausia triacantha was dominant in biomass north of the southern boundary of the Antarctic circumpolar current (SB). Thysanoessa spp. was widely distributed north of the continental slope, while E. superba was distributed from the SB to the slope, where it showed the highest biomass. Juvenile E. superba was distributed offshore near the SB and remained at the surface, but gravid females were dominant in the slope and mainly
occurred in the middle layers (400–600 m). Adult and juvenile E. crystallorophias were found at 200–300 m in the colder water of the continental shelf. In general, the peak biomass of euphausiids was found
in the mid layers of the Ross Sea area. The life span and the number of spawns for major species are also discussed. 相似文献
140.
Hisatomo Taki Peter G. Kevan Blandina F. Viana Fabiana O. Silva & Matthias Buck 《Journal of Applied Entomology》2008,132(3):225-229
To evaluate the role that a trap‐nest cover might have on sampling methodologies, the abundance of each species of trap‐nesting Hymenoptera and the parasitism rate in a Canadian forest were compared between artificially covered and uncovered traps. Of trap tubes exposed at eight forest sites in six trap‐nest boxes, 531 trap tubes were occupied and 1216 individuals of 12 wasp species of four predatory families, Vespidae (Eumeninae), Crabronidae, Sphecidae and Pompilidae emerged over 2 years, and no bee species were found. Results indicated that artificial covering led to a significant increase in the number of nested tubes of Ancistrocerus adiabatus, Ancistrocerus antilope, Ancistrocerus campestris and Auplopus mellipes, and significant effects of covering were not found for the other species. No significant difference in the overall parasitism rate between covered and uncovered traps was noted. These suggested that the covering technique could provide more opportunities for some wasp species to colonize trap nests. 相似文献