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101.
Shingo Kawai Kyousuke Nakata Hiroo Ichizawa Tomoaki Nishida 《Journal of Wood Science》2010,56(2):148-153
There is little evidence concerning the biosynthetic pathways for cyclic diarylheptanoids. We previously demonstrated that
the cyclic diarylheptanoids myricanol and myricanone were biologically synthesized from two molecules of 4-coumaric acid by
the feeding of 4-[8,9-13C2]coumaric acid to young shoots of Myrica rubra. In the present study, using a 13C-labeled compound, we revealed that two molecules of 3-(4-hydroxyphenyl)propionic acid could also be a biosynthetic precursor
of myricanol in M. rubra. These results indicated that both 4-coumaric acid and its dihydro-derivative were incorporated into myricanol. Competitive
feeding experiments with 4-[8,9-13C2]coumaric acid and 3-(4-hydroxyphenyl)-[1-13C]propionic acid were performed in M. rubra to determine the preferential incorporation of these two precursors. 13C-NMR studies indicated that 3-(4-hydroxyphenyl)-[1-13C]propionic acid was preferentially incorporated into myricanol. The data provided evidence for a biosynthetic sequence originating
from 4-coumaric acid and leading to myricanol, through 3-(4-hydroxyphenyl)propionic acid, in M. rubra. 相似文献
102.
Aigo Takeshige Yoichi Miyake Hideaki Nakata Takashi Kitagawa Shingo Kimura 《Fisheries Science》2013,79(6):989-998
Effect of wind stress on the annual catch of Japanese anchovy Engraulis japonicus off northwestern Kyushu for the period between 1963 and 2009 was investigated. Regime shift analysis detected several step changes in catch and environmental variables. Since the mid-1980s, the anchovy catch in the coastal fishery zones has declined, while the catch in the offshore zone has increased. The decline of catch in the coastal zones showed a significant correlation with the long-term variations in prevailing north-northeastward wind stress over the Goto-Nada Sea during spring spawning season. The results indicated that weakened north-northeastward winds caused the recent low recruitment of anchovy through low levels of wind-induced eggs and larval transport from the offshore spawning ground to the coastal nursery areas, resulting in the potential shift of nursery area to the northwestern offshore region. Thus, as well as the growth-favorable ambient temperature, transport process would play a key role on long-term fluctuations in anchovy abundance in these coastal seas. 相似文献
103.
Simulation of the impact of climate change on the egg and larval transport of Japanese anchovy (Engraulis japonicus) off Kyushu Island,the western coast of Japan 下载免费PDF全文
Aigo Takeshige Yoichi Miyake Hideaki Nakata Takashi Kitagawa Shingo Kimura 《Fisheries Oceanography》2015,24(5):445-462
In order to investigate the impact of climate change on egg and larval transport of Japanese anchovy (Engraulis japonicus) off Kyushu Island western Japan, we conducted particle‐tracking simulations on transport success/failure to fishing grounds from 1960 to 2007. The modeled transport success since the mid‐1990s increased and decreased in the offshore and coastal zones, respectively, compared with the 1960s and 1970s. The estimated northward shift of the spawning ground and weakened Tsushima Warm Current contributed to increase in modeled transport success to the offshore zone. Conversely, the weakening trend of the modeled onshore current in the Goto‐Nada Sea combined with the northward shift of the spawning ground resulted in unsuccessful larval transport. These results suggest that fluctuations in juvenile and subadult anchovy catches in this area may be attributable to changes in the physical environment. The present study showed that changes in transport success induced by oceanographic fluctuations related to climate change, have the potential to affect anchovy recruitment off the western coast of Japan. 相似文献
104.
Toshiya Yamamoto Shingo Terakami Norio Takada Sogo Nishio Noriyuki Onoue Chikako Nishitani Miyuki Kunihisa Eiichi Inoue Hiroyoshi Iwata Takeshi Hayashi Akihiro Itai Toshihiro Saito 《Breeding Science》2014,64(4):351-361
Using an F1 population from a cross between Japanese pear (Pyrus pyrifolia Nakai) cultivars ‘Akiakari’ and ‘Taihaku’, we performed quantitative trait locus (QTL) analysis of seven fruit traits (harvest time, fruit skin color, flesh firmness, fruit weight, acid content, total soluble solids content, and preharvest fruit drop). The constructed simple sequence repeat-based genetic linkage map of ‘Akiakari’ consisted of 208 loci and spanned 799 cM; that of ‘Taihaku’ consisted of 275 loci and spanned 1039 cM. Out of significant QTLs, two QTLs for harvest time, one for fruit skin color, and one for flesh firmness were stably detected in two successive years. The QTLs for harvest time were located at the bottom of linkage group (LG) Tai3 (nearest marker: BGA35) and at the top of LG Tai15 (nearest markers: PPACS2 and MEST050), in good accordance with results of genome-wide association study. The PPACS2 gene, a member of the ACC synthase gene family, may control harvest time, preharvest fruit drop, and fruit storage potential. One major QTL associated with fruit skin color was identified at the top of LG 8. QTLs identified in this study would be useful for marker-assisted selection in Japanese pear breeding programs. 相似文献
105.
Biochar application can reduce global warming via carbon (C) sequestration in soils. However, there are few studies investigating its effects on greenhouse gases in rice (Oryza sativa L.) paddy fields throughout the year. In this study, a year-round field experiment was performed in rice paddy fields to investigate the effects of biochar application on methane (CH4) and nitrous oxide (N2O) emissions and C budget. The study was conducted on three rice paddy fields in Ehime prefecture, Japan, for 2 years. Control (Co) and biochar (B) treatments, in which 2-cm size bamboo biochar (2 Mg ha?1) was applied, were set up in the first year. CH4 and N2O emissions and heterotrophic respiration (Rh) were measured using a closed-chamber method. In the fallow season, the mean N2O emission during the experimental period was significantly lower in B (67 g N ha?1) than Co (147 g N ha?1). However, the mean CH4 emission was slightly higher in B (2.3 kg C ha?1) than Co (1.2 kg C ha?1) in fallow season. The water-filled pore space increased more during the fallow season in B than Co. In B, soil was reduced more than in Co due to increasing soil moisture, which decreased N2O and increased CH4 emissions in the fallow season. In the rice-growing season, the mean N2O emission tended to be lower in B (?104 g N ha?1) than Co (?13 g N ha?1), while mean CH4 emission was similar between B (183 kg C ha?1) and Co (173 kg C ha?1). Due to the C release from applied biochar and soil organic C in the first year, Rh in B was higher than that in Co. The net greenhouse gas emission for 2 years considering biochar C, plant residue C, CH4 and N2O emissions, and Rh was lower in B (5.53 Mg CO2eq ha?1) than Co (11.1 Mg CO2eq ha?1). Biochar application worked for C accumulation, increasing plant residue C input, and mitigating N2O emission by improving soil environmental conditions. This suggests that bamboo biochar application in paddy fields could aid in mitigating global warming. 相似文献
106.
Yo Toma Shingo Oomori Asuka Maruyama Hideto Ueno Osamu Nagata 《Soil Science and Plant Nutrition》2016,62(1):69-79
Agricultural fields, including rice (Oryza sativa L.) paddy fields, constitute one of the major sources of atmospheric methane (CH4) and nitrous oxide (N2O). Organic matter application, such as straw and organic fertilizer, enhances CH4 emission from paddy fields. In addition, rice straw management after harvest regulates CH4 emissions in the growing season. The interaction of tillage times and organic fertilizer application on CH4 and N2O emissions is largely unknown. Therefore, we studied the effects of fallow-season tillage times and fertilizer types on CH4 and N2O emissions in paddy fields in Ehime, southwestern Japan. From November 2011 to October 2013, four treatments, two (autumn and spring) or one (spring) in the first year, or two (autumn and spring) or three (autumn, winter, and spring) in the second year times of tillage with chemical or organic fertilizer application, were established. Gas fluxes were measured by the closed-chamber method. Increasing the number of tillage times from one to two decreased succeeding CH4 emission and the emission factor for CH4 (EFCH4) in the rice-growing season, suggesting that the substrate for CH4 production was reduced by autumn and spring tillage in the fallow season. Higher EFCH4 [1.8–2.0 kg carbon (C) ha?1 d?1] was observed when more straw was applied (6.9–7.2 Mg ha?1) in the second year. Organic fertilizer application induced higher CH4 emission just after the application as basal and supplemental fertilizers, especially at a lower straw application rate. This indicated that EFCH4 in the organically managed fields should be determined individually. Organic fertilizer application with two tillage times induced N2O efflux during the rice-growing season in the second year, but N2O emissions were not affected by winter tillage. Although paddy fields can act as an N2O sink because of reduced soil conditions when straw application was high, application of organic C and nitrogen as fertilizer can enhance N2O production by the denitrification process during the growing season, especially in the ripening stage when soil anaerobic conditions became moderate. These results suggest that negative emission factors for N2O (EFN2O) can be applied, and EFN2O of organic fertilizer should be considered during the estimation of N2O emission in the paddy field. 相似文献
107.
Nishida H Tanaka H Kitamura M Hatoya S Sugiura K Inaba T Nakayama M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(8):1071-1074
Progressive ataxia and paralysis in three Miniature Dachshunds were found to be caused by idiopathic sterile pyogranulomatous inflammation of epidural fat between T5 and L4. All dogs were managed by hemilaminectomy and removal of epidural compressive material. Surgical findings and histopathological evaluation were necessary to diagnose epidural pyogranulomatous inflammation. A dog did not regain motor and sensor function after the surgery. Two dogs had exhibited improved neurological function after the surgery, but they recurred. Oral cyclosporine treatment was useful for their long remission. Idiopathic sterile pyogranulomatous inflammation of epidural fat can be considered to be a cause of thoracolumbar myelopathy in dogs. 相似文献
108.
Tsuzuki N Seo JP Yamada K Haneda S Tabata Y Sasaki N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(8):1041-1044
Platelet-rich plasma (PRP) was administered to cattle with hoof defects (10-mm drill hole) to promote sole defect healing. Two types of gels were prepared. One was a mixed gel [compound of gelatin microspheres (GM) incorporated with PRP and alginate] and was used for the test group, while the other was an alginate gel used for the control group. Each hole was filled with one of these gels. The drill hole depth, pressure pain, and hardness of the regenerated tissue were measured for 3 weeks after treatment. These measurements improved significantly in the test group than in the control group. The results suggest that a compound of GM incorporated with PRP and alginate had a hoof-regenerating effect in cattle. 相似文献
109.
Lee HH Kida K Miura R Inokuma H Miyamoto A Kawashima C Haneda S Miyake Y Matsui M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(4):457-464
In peripartum dairy cows, insulin resistance (IR) increases to adjust the direction of energy to lactation after calving. To investigate the effect of prepartum IR on postpartum reproductive performance, the insulin tolerance test (ITT) was applied to 15 cows at 3 weeks (Pre21) and 10 days (Pre10) before the predicted calving date. Blood glucose area under the curve (AUC(glu)) within 120 min after administration of 0.05 IU/kg-BW insulin was calculated. The occurrence of first ovulation, days to first artificial insemination (AI) and first AI conception rate were recorded. Nutritional status postpartum was evaluated by blood chemical analysis. Based on AUC(glu) changes from Pre21 to Pre10, cows were classified into either the AUC-up group (AUC(glu) increase, n=5) or the AUC-down group (AUC(glu) decrease, n=10). There was no difference in the decrease in blood glucose at 30 min after insulin injection between groups, although glucose recovery from 30 to 60 min during the ITT was slow at Pre10 in the AUC-up group. The AUC-up group had a higher number of days to first AI and high glucose, total protein, globulin, γ-glutamyltransferase, triacylglycerol levels and a low albumin-globulin ratio at the 14th day postpartum. The present study infers that prepartum slow glucose recovery rather than insulin sensitivity might increase the potential for subclinical health problems postpartum and thus suppress reproductive performance. During the prepartum transition period, glucose dynamics in the ITT can be considered as a new indicator for the postpartum metabolic status and reproductive performance of dairy cows. 相似文献
110.