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61.
Studies on tillering of the rice plant show that a tiller primordium is always present at each node of the culm (10). Whether the primordllun develops into a tiller depends on such factors as the nutritional status of the plant, the supply of carbohydrates, and the light and temperature conditions (2,3,5,6,7,8,9,11,12,13,14,15,17). 相似文献
62.
Norikuni Ohtake Shinya Yamada Momoko Suzuki Nobuo Takahashi Yoshihiko Takahashi Toshikazu Chinushi 《Soil Science and Plant Nutrition》2013,59(1):247-253
Extract The storage protein of soybean [Glycine max (L.)] seed mainly consists of glycinin, composed of acidic (38 and 45 kDa) and basic (22 kDa) subunits (Kitamura et al. 1976), and β-conglycinin composed of α′- (75 kDa), α- (72 kDa), and β-(52 kDa) subunits (Thanh and Shibasaki 1978). 相似文献
63.
Yoshihiko Takahashi Toshiaki Chinushi Tomio Nakano Kohji Hagino Takuji Ohyama 《Soil Science and Plant Nutrition》2013,59(4):735-739
Abstract We reported in the previous paper (Takahashi et al. 1991) that the deep placement of slow release N fertilizer (coated urea) contributed to a stable increase of soybean (Glycine max L. Merr.) yield. In the previous study we observed that the deep placement of coated urea did not depress appreciably the nitrogen fixation by root nodules although fertilizer N was efficiently utilized. We assumed that the N absorbed from the roots in the deep layers did not cause nodule senescence, contributed to the maintenance of the leaf activity during the maturation stage, and that the increase in the availability of carbohydrate and N improved seed production. In the current report the effects of placement of coated urea fertilizer on the root growth and activity were studied by measuring the root dry weight and Rb absorption activity. 相似文献
64.
65.
Halberg F Cornélissen G Katinas G Syutkina EV Sothern RB Zaslavskaya R Halberg F Watanabe Y Schwartzkopff O Otsuka K Tarquini R Frederico P Siggelova J 《Journal of circadian rhythms》2003,1(1):2-61
Afew puzzles relating to a small fraction of my endeavors in the 1950s are summarized herein, with answers to a few questions of the Editor-in-Chief, to suggest that the rules of variability in time complement the rules of genetics as a biological variability in space. I advocate to replace truisms such as a relative constancy or homeostasis, that have served bioscience very well for very long. They were never intended, however, to lower a curtain of ignorance over everyday physiology. In raising these curtains, we unveil a range of dynamics, resolvable in the data collection and as-one-goes analysis by computers built into smaller and smaller devices, for a continued self-surveillance of the normal and for an individualized detection of the abnormal. The current medical art based on spotchecks interpreted by reference to a time-unqualified normal range can become a science of time series with tests relating to the individual in inferential statistical terms. This is already doable for the case of blood pressure, but eventually should become possible for many other variables interpreted today only based on the quicksand of clinical trials on groups. These ignore individual differences and hence the individual's needs. Chronomics (mapping time structures) with the major aim of quantifying normalcy by dynamic reference values for detecting earliest risk elevation, also yields the dividend of allowing molecular biology to focus on the normal as well as on the grossly abnormal. 相似文献
66.
A novel postharvest UV-C treatment to reduce chilling injury (membrane damage,browning and chlorophyll degradation) in banana peel 总被引:1,自引:0,他引:1
To investigate the mode of action of UV-C to alleviate CI in banana. Banana [Musa (AAA group), Cavendish subgroup cv. Cavendish] fruits were treated with UV-C at dosages of 0.03 kJ m−2 prior to storage at 8 or 25 °C. UV-C treatment reduced both the incidence and severity of banana fruits stored under low temperature. UV-C treatment reduced membrane damage indicated by lower activity of lipoxygenase (LOX) and malondialdehyde (MDA) content. In additions, the in vitro polyphenol oxidase (PPO) activity was activated when fruits were stored at CI temperature and UV-C treatment could inhibit the PPO activity. UV-C treatment also delayed yellowing and chlorophyll (Chl) degradation due to the inhibition of chlorophyllase and chl-degrading peroxidase activities. Furthermore, the reduction of ethylene production and respiration rate by UV-C treatment results in extended postharvest shelf life of banana. These finding suggest that the loss of cellular compartments in consequence of membrane degradation, combined with the increase of PPO activity, might contribute to the development of CI in banana peel. UV-C treatment may play an important role in maintained membrane integrity and inhibited PPO activity, reducing the severity of CI symptom and delayed ripening in banana. This novel technique may offer an advance in postharvest handling of bananas and other chilling-sensitive commodities in order to reduce postharvest losses resulting from CI. 相似文献
67.
Natsumi SHIMIZU Kimihiro UENO Ena KURITA Seung-Wook SHIN Takuji NISHIHARA Tomoko AMANO Masayuki ANZAI Satoshi KISHIGAMI Hiromi KATO Tasuku MITANI Yoshihiko HOSOI Kazuya MATSUMOTO 《The Journal of reproduction and development》2014,60(3):179-186
In the mammalian testis, the ubiquitin-proteasome system plays important roles in the process that promotes the formation of
mature sperm. We recently identified zygote-specific proteasome
assembly phaperone (ZPAC), which is specifically expressed in the mouse
gonads and zygote. ZPAC mediates a unique proteasome assembly pathway in the zygote, but the expression profile and function
of ZPAC in the testis is not fully understood. In this study, we investigated the possible role of ZPAC during mouse
spermatogenesis. First, we analyzed the expression of ZPAC and 20S proteasome subunit α4/PSMA7 in the adult mouse testis.
ZPAC and α4 were expressed in spermatogonia, spermatocytes, and round spermatids. In elongating spermatids, ZPAC was
expressed until step 10, whereas expression of α4 persisted until step 12. We then examined the expression profile of ZPAC
and α4 in a mouse model of experimental unilateral cryptorchidism. Consistent with appearance of morphologically impaired
germ cells following cryptorchidism, the ZPAC protein level was significantly decreased at 4 days post induction of
experimental cryptorchidism (D4) compared with the intact testis, although the amount of α4 protein persisted at least until
D10. Moreover, intense ZPAC staining was co-localized with staining of annexin V, an early indicator of apoptosis in
mammalian cells, in germ cells of cryptorchid testis, but ZPAC was also expressed in germ cells showing no detectable
expression of annexin V. These results suggest that ZPAC plays a role during spermatogenesis and raises the possibility that
20S proteasome mediated by ZPAC may be involved in the regulation of germ cell survival during spermatogenesis. 相似文献
68.
Microscopic processes of shearing fracture of old wood, examined using the acoustic emission technique 总被引:1,自引:0,他引:1
Kosei Ando Yoshihiko Hirashima Mina Sugihara Sakiko Hirao Yasutoshi Sasaki 《Journal of Wood Science》2006,52(6):483-489
We examined the process of microscopic fracturing peculiar to old wood, based on the generation characteristics of acoustic
emission (AE) events and fracture surface analysis. The shearing tests of old wood obtained from construction-derived lumber
and new wood within 3 years after lumbering were performed in accordance with the Japanese Industrial Standards (JIS Z 2101-1994).
The species of wood used in this study was Japanese red pine. The old wood had been used as a beam in a building for 270 years.
The number of the occurrences of AEs at low load levels was larger in the old wood than in the new wood. As a result of analyzing
the AE amplitude distributions, we found that the period in which AEs with small amplitudes were frequently generated was
longer in the old wood than in the new wood. Also, the fracture surfaces after the final rupture under scanning electron microscope
showed more uneven and complicated surfaces in the old wood. Based on the above findings, we presume that during the shearing
test the old wood underwent a relatively long and stable progress of microcracking before the final fracture. 相似文献
69.
Grzegorz Cyra Chiaki Tanaka Masahiro Yoshinobu Yoshihiko Nishino 《Journal of Wood Science》1998,44(3):169-176
The purpose of this study was to investigate the effects of changes in the helical angle of the router bit on the acoustic emission (AE) signal for various workpiece grain angles. The helical angle varied from 0° to 50° at 10° increments. The workpiece grains were oriented from 0 degrees (cutting parallel to the grain), through 90° (cutting end of the grain), to 165° at 15° increments. The AE signals and machined surface roughness were measured in an attempt to clarify the relations between them. The results were summarized as follows: (1) The AE signals were lowest in the with the grain cutting zones and slightly increased in the against the grain cutting zones; they rapidly reached the highest values at the 135°–165° grain angles. The greater the helical angle of the router bit, the smaller were the AE count rates for each grain angle investigated. There was no significant change in AE generation for helical angles of 0° and 10°. Moreover, the greater the feed rate, the greater was the AE count rate for every cutting condition investigated. (2) The surface roughness, similar to the AE count rate, had the lowest values in the with the grain cutting zones, slightly increased until the 120° grain angle, and then rapidly become extremely rough, reaching a maximum at the grain angles of 135°–150°. There was no remarkable change in the machined surface roughness while routing with the grain using the router bit of greater helical angle. However, when routing against the grain, the greater the helical angle the smoother was the machined surface. (3) There were correlations between the AE count rate and the machined surface roughness for each helical angle investigated. Therefore, acoustic emission has shown promise for monitoring and controlling the routing operation, including various grain angles and helical angles of the router bit. 相似文献
70.
Summary A durum wheat cultivar Langdon (LDN) and fourteen disomic D genome chromosome substitution lines of Langdon, where A or B genome chromosomes were replaced with homoeologous D genome chromosomes of Chinese Spring (CS), were used to assess the compensatory effect of the D genome chromosomes on photosynthetic rates at tetraploid level. The LDN 1D(1B) and LDN 3D(3B) lines showed significantly higher photosynthetic rates than Langdon, whereas LDN 1D(1A) and LDN 3D(3A) lines were not greatly different from Langdon. It appears that chromosomes 1B and 3B decrease photosynthesis. This suggests the differentiation of the effects on the photosynthesis within the first and third homoeologous groups. Substitution with the 2D chromosomes did not compensate the effects of either 2A or 2B chromosomes as it reduced photosynthetic rate compared to plant with either chromosomes 2A or 2B. Tetra CS had a higher photosynthetic rate than CS and Penta CS. The photosynthetic rate of CS was similar to that of Penta CS, which lacked one set of D genome. The results suggest that it may be possible to increase photosynthesis, if both sets of the D genome were entirely removed from hexaploid wheat. However, it is difficult to conclude that the lower rate of photosynthesis of the hexaploids was mainly attributable to D genome chromosome effects, because we did not find a dose dependent effect of D genome. Homoeologous differentiation of chromosomes may be involved in photosynthesis. 相似文献