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991.
This study introduces a conceptually new solvent suppression scheme with adiabatic inversion pulses for 1H-detected multidimensional solid-state NMR (SSNMR) of biomolecules and other systems, which is termed “Solvent suppression of Liquid signal with Adiabatic Pulse” (SLAP). 1H-detected 2D 13C/1H SSNMR data of uniformly 13C- and 15N-labeled GB1 sample using ultra-fast magic angle spinning at a spinning rate of 60 kHz demonstrated that the SLAP scheme showed up to 3.5-fold better solvent suppression performance over a traditional solvent-suppression scheme for SSNMR, MISSISSIPPI (Zhou and Rienstra, J Magn Reson 192:167–172, 2008) with 2/3 of the average RF power.
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Vertical seed dispersal, which plays a key role in plant escape and/or expansion under climate change, was recently evaluated for the first time using negative correlation between altitudes and oxygen isotope ratio of seeds. Although this method is innovative, its applicability to other plants is unknown. To explore the applicability of the method, we regressed altitudes on δ18O of seeds of five woody species constituting three families in temperate forests in central Japan. Because climatic factors, including temperature and precipitation that influence δ18O of plant materials, demonstrate intensive seasonal fluctuation in the temperate zone, we also evaluated the effect of fruiting season of each species on δ18O of seeds using generalized linear mixed models (GLMM). Negative correlation between altitudes and δ18O of seeds was found in four of five species tested. The slope of regression lines tended to be lower in late‐fruiting species. The GLMM analysis revealed that altitudes and date of fruiting peak negatively affected δ18O of seeds. These results indicate that the estimation of vertical seed dispersal using δ18O of seeds can be applicable for various species, not just confined to specific taxa, by identifying the altitudes of plants that produced seeds. The results also suggest that the regression line between altitudes and δ18O of seeds is rather species specific and that vertical seed dispersal in late‐fruiting species is estimated at a low resolution due to their small regression slopes. A future study on the identification of environmental factors and plant traits that cause a difference in δ18O of seeds, combined with an improvement of analysis, will lead to effective evaluation of vertical seed dispersal in various species and thereby promote our understanding about the mechanism and ecological functions of vertical seed dispersal. 相似文献
996.
Potentially, golf courses could act as wildlife refuges under adequate golf course management. We assessed the impacts of
golf course managements on arthropod communities by analyzing arthropod community data. Arthropods were collected using a
sweeping-net method from turf areas. Information of management applied in each golf course such as frequency of chemical use,
length of grass was obtained by field measurements and also from interviews based on management records with green keepers.
In total, 92 invertebrate families were collected. Of 44 frequently appearing families, the number of individuals in 22 arthropods
families such as Delphacidae and Deltocephalidae were associated with some kind of course management features. Length of grass
was the most influential factor to those families. After removing the effect of the grass length by regression analysis, herbicide
affected six families. The effects of frequency of the use of fungicide and insecticide were not detected in this study. 相似文献
997.
K Koike M Hamada N Tanaka K I Otsuka K Ogasahara M Koike 《The Journal of biological chemistry》1974,249(12):3836-3842
998.
Makoto Watanabe Michiko Umemoto-Yamaguchi Takayoshi Koike Takeshi Izuta 《Landscape and Ecological Engineering》2010,6(2):181-190
We investigated the effects of ozone (O3) and/or elevated CO2 concentration ([CO2]) on growth and photosynthetic traits of Fagus crenata seedlings. Two-year-old seedlings were grown in four experimental treatments comprising two O3 treatments (charcoal-filtered air and 100 nmol mol−1 O3; 6 h/day, 3 days/week) in combination with two CO2 treatments (350 and 700 μmol mol−1) for 18 weeks in environmental control growth chambers. The four treatments were designated as control, elevated O3, elevated CO2, and elevated CO2 + O3. Dry matter growth of the seedlings was greater in elevated CO2 + O3 than in elevated CO2. In elevated CO2 + O3, a marked increase of second-flush leaves, considered a compensative response to O3, was observed. The net photosynthetic rate of first-flush leaves in elevated CO2 + O3 increased earlier and was maintained for a longer period of time than that in elevated CO2. Because emergence of second-flush leaves of F. crenata is greatly affected by the amount of assimilation products of first-flush leaves in current year, we consider that an early
increase in the net photosynthetic rate of first-flush leaves contributed to the marked increase in second-flush leaf emergence
under elevated CO2 + O3. These results imply that we must account for changes in compensative capacity with respect to not only morphological traits
but also phenological traits and physiological functions such as photosynthesis when evaluating effects of O3 on F. crenata under elevated [CO2]. 相似文献
999.
Atsushi Kato Jackie Hollinshead Yukiko Yamashita Shinpei Nakagawa Yuriko Koike Isao Adachi Chu-Yi Yu George W.J. Fleet Robert J. Nash 《Phytochemistry letters》2010,3(4):230-233
The distribution of pyrrolidine-type iminosugars with a long-side chain appears to be restricted to the relatively unrelated plant families Moraceae, Campanulaceae, and Hyacinthaceae. In a search for glycosidase inhibitors in these plant families, we isolated the 1,4-dideoxy-1,4-imino-d-lyxitol (DIL) glucoside bearing the 1,2,11-trihydroxyundec-4-ene side chain at the C-1α position from the roots of Adenophora triphylla. This iminosugar was a powerful and selective inhibitor of coffee bean α-galactosidase, with an IC50 value of 8 μM. 相似文献
1000.
Masazumi Kayama Kobayashi Makoto Mutsumi Nomura Fuyuki Satoh Takayoshi Koike 《Landscape and Ecological Engineering》2009,5(2):125-135
Japanese larch (Larix kaempferi) grows at a relatively high rate in northern Japan, even in serpentine soil. Serpentine soil has high concentrations of heavy
metals (Ni, Cr), excessive Mg, and is nutrient deficient. These factors often suppress plant growth. We examined the mechanisms
of Japanese larch’s tolerance to serpentine soil. We compared growth, photosynthetic capacity, and concentrations of elements
in needles and roots between larch seedlings growing in serpentine soil and in nonserpentine (i.e., brown forest) soil. Dry
mass of needles, stems, and branches were lower in seedlings grown on serpentine soil than in those grown on brown forest
soil. There were lower concentrations of phosphorus and potassium in seedlings grown on serpentine soil than in those grown
on brown forest soil. Seedlings growing on serpentine soil had lower Ni in plant organs. Our results suggest that larch seedlings
grown on serpentine soil were able to exclude toxic elements. Moreover, the photosynthetic capacity and nitrogen concentration
in needles was almost the same for seedlings grown in the two soil types. A wide range in growth was observed among individuals
grown on both soil types. This may be regulated by nitrogen storage in the roots. 相似文献