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81.
Komatsu T Hirano T Songkram C Kawachi E Kagechika H 《Bioorganic & medicinal chemistry》2007,15(9):3115-3126
Thyroid hormones play important roles in growth, development and homeostasis, and disruption of their functions induces serious disease, so novel synthetic thyroid hormone analogues are candidates for clinical application. We designed and synthesized novel diphenylamine derivatives with a thiazolidinedione moiety as the terminal polar group as thyroid hormone receptor (TR) antagonists. Compounds bearing an appropriately sized N-alkyl group showed antagonistic activities towards both the hTRalpha1 and hTRbeta1 subtypes. 相似文献
82.
Tomoya Iwata 《Ecological Research》2007,22(4):619-628
In headwater streams, many aquatic insects rely on terrestrial detritus, while their emergence from streams often subsidizes
riparian generalist predators. However, spatial variations in such reciprocal trophic linkages remain poorly understood. The
present study, conducted in a northern Japanese stream and the surrounding forest, showed that pool–riffle structure brought
about heterogeneous distributions of detritus deposits and benthic aquatic insects. The resulting variations in aquatic insect
emergence influenced the distributions of riparian web-building spiders. Pools with slow current stored greater amounts of
detritus than riffles, allowing more benthic aquatic insects to develop in pools. The greater larval biomass in pools and
greater tendency for riffle insects to drift into pools at metamorphosis resulted in an emergence rate of aquatic insects
from pools that was some four to five times greater than from riffles. In the riparian forest, web-building spiders (Tetragnathidae
and Linyphiidae) were distributed in accordance with the emergence rates of aquatic insects, upon which both spider groups
heavily depended. Consequently, the riparian strips bordering pools had a density of tetragnathid spiders that was twice as
high as that of the riparian strips adjacent to riffles. Moreover, although limitations of vegetation structure prevented
the aggregation of linyphiid spiders around pools, linyphiid density normalized by shrub density was higher in habitats adjacent
to pools than those adjacent to riffles. The results indicated that stream geomorphology, which affects the storage of terrestrial
organic material and the export of such material to riparian forests via aquatic insect emergence, plays a role in determining
the strength of terrestrial–aquatic linkages in headwater ecosystems. 相似文献
83.
Yamamoto M Kamata T DO ND Adachi Y Kinjo M Ando T 《Bioscience, biotechnology, and biochemistry》2007,71(11):2860-2863
Female moths of Lyclene dharma dharma (Arctiidae, Lithosiinae) produced three pheromone components (I-III), which strongly stimulated male antennae. Using GC-MS analysis and chemical derivatizations, the following structures were estimated: 6-methyl-2-octadecanone (I), 14-methyl-2-octadecanone (II), and 6,14-dimethyl-2-octadecanone (III). While the stereochemistry of the chiral centers could not be determined because it was difficult to collect a sufficient amount of the natural pheromone, the plain structures of I and II were confirmed by synthesis of the racemic mixtures starting from diols. These methyl-branched ketones have not been identified as a natural product, indicating that they constitute a new chemical group of lepidopteran female sex pheromones. 相似文献
84.
Dillapiol and Apiol as specific inhibitors of the biosynthesis of aflatoxin G1 in Aspergillus parasiticus 总被引:1,自引:0,他引:1
Razzaghi-Abyaneh M Yoshinari T Shams-Ghahfarokhi M Rezaee MB Nagasawa H Sakuda S 《Bioscience, biotechnology, and biochemistry》2007,71(9):2329-2332
Dillapiol was isolated from the essential oil of dill as a specific inhibitor of aflatoxin G1 production. It inhibited aflatoxin G1 production by Aspergillus parasiticus with an IC50 value of 0.15 microM without inhibiting aflatoxin B1 production or fungal growth. Apiol and myristicin, congeners of dillapiol, showed similar activity with IC50 values of 0.24 and 3.5 microM, respectively. 相似文献
85.
Youhei Tanaka Naohiro Hayashibara Tomoya Enokido Makoto Takizawa 《Cluster computing》2007,10(1):81-93
In this paper, we discuss how to realize fault-tolerant applications on distributed objects. Servers supporting objects can
be fault-tolerant by taking advantage of replication and checkpointing technologies. However, there is no discussion on how
application programs being performed on clients are tolerant of clients faults. For example, servers might block in the two-phase
commitment protocol due to the client fault. We newly discuss how to make application programs fault-tolerant by taking advantage
of mobile agent technologies where a program can move from a computer to another computer in networks. An application program
to be performed on a faulty computer can be performed on another operational computer by moving the program in the mobile
agent model. In this paper, we discuss a transactional agent model where a reliable and efficient application for manipulating objects in multiple computers is realized in the mobile agent
model. In the transactional agent model, only a small part of the application program named routing subagent moves around computers. A routing subagent autonomously finds a computer which to visit next. We discuss a hierarchical navigation
map which computer should be visited price to another computer in a transactional agent. A routing subagent makes a decision
on which computer visit for the hierarchical navigation map. Programs manipulating objects in a computer are loaded to the
computer on arrival of the routing subagent in order to reduce the communication overhead. This part of the transactional
agent is a manipulating subagent. The manipulation subagent still exists on the computer even after the routing subagent leaves the computer in order to hold
objects until the commitment. We assume every computer may stop by fault while networks are reliable. There are kinds of faulty
computers for a transactional agent; current, destination, and sibling computers where a transactional agent now exists, will move, and has visited, respectively. The types of faults are detected
by neighbouring manipulation subagents by communicating with each other. If some of the manipulation subagents are faulty,
the routing subagent has to be aborted. However, the routing subagent is still moving. We discuss how to efficiently deliver
the abort message to the moving routing subagent. We evaluate the transactional agent model in terms of how long it takes
to abort the routing subagent if some computer is faulty.
相似文献
Makoto TakizawaEmail: |
86.
The complete nucleotide sequence of the cucumber (C. sativus L. var. Borszczagowski) chloroplast genome has been determined. The genome is composed of 155,293 bp containing a pair of
inverted repeats of 25,191 bp, which are separated by two single-copy regions, a small 18,222-bp one and a large 86,688-bp
one. The chloroplast genome of cucumber contains 130 known genes, including 89 protein-coding genes, 8 ribosomal RNA genes
(4 rRNA species), and 37 tRNA genes (30 tRNA species), with 18 of them located in the inverted repeat region. Of these genes,
16 contain one intron, and two genes and one ycf contain 2 introns. Twenty-one small inversions that form stem-loop structures, ranging from 18 to 49 bp, have been identified.
Eight of them show similarity to those of other species, while eight seem to be cucumber specific. Detailed comparisons of
ycf2 and ycf15, and the overall structure to other chloroplast genomes were performed. 相似文献
87.
Kazutaka Sawada Tomoya Sato Hiroshi Hamajima Lahiru Niroshan Jayakody Miyo Hirata Mikako Yamashiro Marie Tajima Susumu Mitsutake Koji Nagao Keisuke Tsuge Fumiyoshi Abe Kentaro Hanada Hiroshi Kitagaki 《Applied and environmental microbiology》2015,81(11):3688-3698
In nature, different microorganisms create communities through their physiochemical and metabolic interactions. Many fermenting microbes, such as yeasts, lactic acid bacteria, and acetic acid bacteria, secrete acidic substances and grow faster at acidic pH values. However, on the surface of cereals, the pH is neutral to alkaline. Therefore, in order to grow on cereals, microbes must adapt to the alkaline environment at the initial stage of colonization; such adaptations are also crucial for industrial fermentation. Here, we show that the yeast Saccharomyces cerevisiae, which is incapable of synthesizing glucosylceramide (GlcCer), adapted to alkaline conditions after exposure to GlcCer from koji cereal cultured with Aspergillus kawachii. We also show that various species of GlcCer derived from different plants and fungi similarly conferred alkali tolerance to yeast. Although exogenous ceramide also enhanced the alkali tolerance of yeast, no discernible degradation of GlcCer to ceramide was observed in the yeast culture, suggesting that exogenous GlcCer itself exerted the activity. Exogenous GlcCer also increased ethanol tolerance and modified the flavor profile of the yeast cells by altering the membrane properties. These results indicate that GlcCer from A. kawachii modifies the physiology of the yeast S. cerevisiae and demonstrate a new mechanism for cooperation between microbes in food fermentation. 相似文献
88.
Akira Watanabe Kazumi Hiraga Masako Suda Hideaki Yukawa Masayuki Inui 《Applied and environmental microbiology》2015,81(12):4173-4183
The Corynebacterium alkanolyticum
xylEFGD gene cluster comprises the xylD gene that encodes an intracellular β-xylosidase next to the xylEFG operon encoding a substrate-binding protein and two membrane permease proteins of a xyloside ABC transporter. Cloning of the cluster revealed a recombinant β-xylosidase of moderately high activity (turnover for p-nitrophenyl-β-d-xylopyranoside of 111 ± 4 s−1), weak α-l-arabinofuranosidase activity (turnover for p-nitrophenyl-α-l-arabinofuranoside of 5 ± 1 s−1), and high tolerance to product inhibition (Ki for xylose of 67.6 ± 2.6 mM). Heterologous expression of the entire cluster under the control of the strong constitutive tac promoter in the Corynebacterium glutamicum xylose-fermenting strain X1 enabled the resultant strain X1EFGD to rapidly utilize not only xylooligosaccharides but also arabino-xylooligosaccharides. The ability to utilize arabino-xylooligosaccharides depended on cgR_2369, a gene encoding a multitask ATP-binding protein. Heterologous expression of the contiguous xylD gene in strain X1 led to strain X1D with 10-fold greater β-xylosidase activity than strain X1EFGD, albeit with a total loss of arabino-xylooligosaccharide utilization ability and only half the ability to utilize xylooligosaccharides. The findings suggest some inherent ability of C. glutamicum to take up xylooligosaccharides, an ability that is enhanced by in the presence of a functional xylEFG-encoded xyloside ABC transporter. The finding that xylEFG imparts nonnative ability to take up arabino-xylooligosaccharides should be useful in constructing industrial strains with efficient fermentation of arabinoxylan, a major component of lignocellulosic biomass hydrolysates. 相似文献
89.
Life history strategy and adult and larval behavior of Macrodiplosis selenis (Diptera: Cecidomyiidae), a species that induces leaf‐margin fold galls on deciduous Quercus (Fagaceae) 下载免费PDF全文
Wanggyu Kim Kiyoko Matsunaga Naohisa Gyoutoku Kazunori Matsuo Tsuneo Minami Junichi Yukawa 《Entomological Science》2015,18(4):470-478
Life historical, behavioral and ecological traits of Macrodiplosis selenis, which induces leaf‐margin fold galls on Quercus serrata, Q. mongolica and Q. dentata (Fagaceae) in Japan and South Korea, were studied. Daily activity and larval development indicate that M. selenis is a diurnal and univoltine gall midge. In April, females lay their eggs both on upper and under surfaces of fresh leaves. The duration of the egg stage varies from 5 to 9 days, depending on daily temperatures. Hatched larvae crawl to the upper surface of the leaf margin, where they start to induce galls. Larvae become full‐grown in October, drop to the ground in November and overwinter in cocoons on the ground, while larvae of congeners mature in May and drop to the ground in June. A relatively long period of the second larval stadium from July to October on the host trees seems to be effective for M. selenis in avoiding summer mortalities caused by predation and aridity on the ground and by ectoparasitoids that attack mature larvae or pupae on the host leaves. The spatial distribution pattern of M. selenis leaf galls is contagious and the mean gall density per leaf is significantly correlated with the mean crowding. This study adds new insights of life history strategy and adult and larval behavioral pattern to the ecological knowledge of gall midges, and these kinds of information are essential for further studies of M. selenis population dynamics and interactions with other Quercus‐associated herbivores. 相似文献
90.
A major challenge associated with the fermentation of lignocellulose-derived hydrolysates is improved ethanol production in the presence of fermentation inhibitors, such as acetic and formic acids. Enhancement of transaldolase (TAL) and formate dehydrogenase (FDH) activities through metabolic engineering successfully conferred resistance to weak acids in a recombinant xylose-fermenting Saccharomyces cerevisiae strain. Moreover, hybridization of the metabolically engineered yeast strain improved ethanol production from xylose in the presence of both 30 mM acetate and 20 mM formate. Batch fermentation of lignocellulosic hydrolysate containing a mixture of glucose, fructose and xylose as carbon sources, as well as the fermentation inhibitors, acetate and formate, was performed for five cycles without any loss of fermentation capacity. Long-term stability of ethanol production in the fermentation phase was not only attributed to the coexpression of TAL and FDH genes, but also the hybridization of haploid strains. 相似文献