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Hiroshi Abe Takeshi Shimoda Jun Ohnishi Soichi Kugimiya Mari Narusaka Shigemi Seo Yoshihiro Narusaka Shinya Tsuda Masatomo Kobayashi 《BMC plant biology》2009,9(1):97
Background
The western flower thrips (Frankliniella occidentalis [Pergande]) is one of the most important insect herbivores of cultivated plants. However, no pesticide provides complete control of this species, and insecticide resistance has emerged around the world. We previously reported the important role of jasmonate (JA) in the plant's immediate response to thrips feeding by using an Arabidopsis leaf disc system. In this study, as the first step toward practical use of JA in thrips control, we analyzed the effect of JA-regulated Arabidopsis defense at the whole plant level on thrips behavior and life cycle at the population level over an extended period. We also studied the effectiveness of JA-regulated plant defense on thrips damage in Chinese cabbage (Brassica rapa subsp. pekinensis). 相似文献23.
24.
Nam Jin Noh Yowhan Son Rae Hyun Kim Kyung Won Seo Jin Woo Koo In Hyeop Park Young Jin Lee Kyeong Hak Lee Yeong Mo Son 《Journal of Plant Biology》2007,50(4):461-466
Above- and belowground biomass and nitrogen (N) and phosphorus (P) distribution within threeQuercus acutissima stands were investigated in central Korea. The average age (year) and diameter at breast height (DBH, cm) were 10.8 and 7.9
for Stand 1, 38.2 and 17.1 for Stand 2, and 44.0 and 20.7 for Stand 3, respectively. Fifteen trees were destructively harvested
for dimension analysis of component biomass (stem wood, stem bark, foliage, branches, and roots) plus N and P concentrations.
Total biomass (t ha-1) was 88.7 for Stand 1, 154.9 for Stand 2, and 278.1 for Stand 3 while N and P contents in all tree components (kg ha-1) were 483.3 and 52.2, 697.1 and 55.0, and 1113.9 and 83.7. Nitrogen concentrations were highest in the foliage, followed
by the stem bark, branches or roots, and stem wood. In contrast, P concentrations were greatest in the roots, then foliage,
branches, stem bark, and stem wood. In general, N and P concentrations in these components significantly decreased with tree
age and DBH, while N and P contents significantly increased with age and size. These relationships were stronger for size
than for age. Our current data could be utilized to estimate N and P budgets for silvicultural practices, including fertilization,
thinning, and harvesting. 相似文献
25.
ANDRÉIA SILVA FLORES RÉA M. CORRÊA ELIANA R. FORNI-MARTINS ANA M. G. AZEVEDO TOZZI 《Botanical journal of the Linnean Society. Linnean Society of London》2006,151(2):271-277
Chromosome numbers were counted for 23 species of Crotalaria native to Brazil. Among these data there were new counts for 15 taxa, and some confirmed previous reports or represented numbers that were different from those cited previously. The chromosome numbers most frequently found were 2 n = 16 and 2 n = 32. Only C. incana L. had 2 n = 14 and C. tweediana Benth. had 2 n = 54. The counts 2 n = 32 and 54 were found in species of section Calycinae and 2 n = 16 and 14 in species of section Chrysocalycinae . The data revealed the importance of chromosomal parameters in the characterization of sections Calycinae and Chrysocalycinae in Brazil. We discuss the systematic significance and evolutionary aspects for the genus, comparing the results with the two sections that are native in Brazil. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 271–277. 相似文献
26.
Eun Hye Lee Seon Sook Kim Seul Lee Kwan-Hyuck Baek Su Ryeon Seo 《The Journal of biological chemistry》2015,290(34):21019-21031
Pituitary adenylate cyclase-activating peptide (PACAP) is a neurotrophic peptide involved in a wide range of nervous functions, including development, differentiation, and survival, and various aspects of learning and memory. Here we report that PACAP induces the expression of regulator of calcineurin 1 (RCAN1, also known as DSCR1), which is abnormally expressed in the brains of Down syndrome patients. Increased RCAN1 expression is accompanied by activation of the PKA-cAMP response element-binding protein pathways. EMSA and ChIP analyses demonstrate the presence of a functional cAMP response element in the RCAN1 promoter. Moreover, we show that PACAP-dependent neuronal differentiation is significantly disturbed by improper RCAN1 expression. Our data provide the first evidence of RCAN1, a Down syndrome-related gene, as a novel target for control of the neurotrophic function of PACAP. 相似文献
27.
Geon Ha Kim Seun Jeon Kiho Im Hunki Kwon Byung Hwa Lee Ga Young Kim Hana Jeong Noh Eul Han Sang Won Seo Hanna Cho Young Noh Sang Eon Park Hojeong Kim Jung Won Hwang Cindy W. Yoon Hee Jin Kim Byoung Seok Ye Ju Hee Chin Jung-Hyun Kim Mee Kyung Suh Jong Min Lee Sung Tae Kim Mun-Taek Choi Mun Sang Kim Kenneth M Heilman Jee Hyang Jeong Duk L. Na 《PloS one》2015,10(4)
The purpose of this study was to investigate if multi-domain cognitive training, especially robot-assisted training, alters cortical thickness in the brains of elderly participants. A controlled trial was conducted with 85 volunteers without cognitive impairment who were 60 years old or older. Participants were first randomized into two groups. One group consisted of 48 participants who would receive cognitive training and 37 who would not receive training. The cognitive training group was randomly divided into two groups, 24 who received traditional cognitive training and 24 who received robot-assisted cognitive training. The training for both groups consisted of daily 90-min-session, five days a week for a total of 12 weeks. The primary outcome was the changes in cortical thickness. When compared to the control group, both groups who underwent cognitive training demonstrated attenuation of age related cortical thinning in the frontotemporal association cortices. When the robot and the traditional interventions were directly compared, the robot group showed less cortical thinning in the anterior cingulate cortices. Our results suggest that cognitive training can mitigate age-associated structural brain changes in the elderly.
Trial Registration
ClnicalTrials.gov NCT01596205 相似文献28.
Marten H Hyun T Gomi K Seo S Hedrich R Roelfsema MR 《The Plant journal : for cell and molecular biology》2008,55(4):698-708
Light-induced stomatal opening in C3 and C4 plants is mediated by two signalling pathways. One pathway is specific for blue light and involves phototropins, while the second pathway depends on photosyntheticaly active radiation (PAR). Here, the role of Nt MPK4 in light-induced stomatal opening was studied, as silencing of this MAP kinase stimulates stomatal opening. Stomata of Nt MPK4-silenced plants do not close in elevated atmospheric CO2 , and show a reduced response to PAR. However, stomatal closure can still be induced by abscisic acid. Measurements using multi-barrelled intracellular micro-electrodes showed that CO2 activates plasma membrane anion channels in wild-type Nicotiana tabacum guard cells, but not in Nt MPK4-silenced cells. Anion channels were also activated in wild-type guard cells after switching off PAR. In approximately half of these cells, activation of anion channels was accompanied by an increase in the cytosolic free Ca2+ concentration. The activity of anion channels was higher in cells showing a parallel increase in cytosolic Ca2+ than in those with steady Ca2+ levels. Both the darkness-induced anion channel activation and Ca2+ signals were repressed in Nt MPK4-silenced guard cells. These data show that CO2 and darkness can activate anion channels in a Ca2+ -independent manner, but the anion channel activity is enhanced by parallel increases in the cytosolic Ca2+ concentration. Nt MPK4 plays an essential role in CO2 - and darkness-induced activation of guard-cell anion channels, through Ca2+ -independent as well as Ca2+ -dependent signalling pathways. 相似文献
29.
Katie D. Rosenthal Michael P. Hughes Benjamin R. Luginbuhl Niva A. Ran Akchheta Karki Seo‐Jin Ko Huawei Hu Ming Wang Harald Ade Thuc‐Quyen Nguyen 《Liver Transplantation》2019,9(27)
Open‐circuit voltage (VOC) losses in organic photovoltaics (OPVs) inhibit devices from reaching VOC values comparable to the bandgap of the donor–acceptor blend. Specifically, nonradiative recombination losses (?Vnr) are much greater in OPVs than in silicon or perovskite solar cells, yet the origins of this are not fully understood. To understand what makes a system have high or low loss, an investigation of the nonradiative recombination losses in a total of nine blend systems is carried out. An apparent relationship is observed between the relative domain purity of six blends and the degree of nonradiative recombination loss, where films exhibiting relatively less pure domains show lower ?Vnr than films with higher domain purity. Additionally, it is shown that when paired with a fullerene acceptor, polymer donors which have bulky backbone units to inhibit close π–π stacking exhibit lower nonradiative recombination losses than in blends where the polymer can pack more closely. This work reports a strategy that ensures ?Vnr can be measured accurately and reports key observations on the relationship between ?Vnr and properties of the donor/acceptor interface. 相似文献
30.