Effects of underdrainage in lowland poorly drained paddy field     

Ryosuke Tateoka 《Soil Science and Plant Nutrition》2013,59(1):80-84

The lowland poorly drained paddy field may be handicapped in general, to the better drained paddy field in soil productivity level for rice crops in Japan. This is principally responsible for the prevalence of reducing characteristics in soils because of the high waterlogging condition all the year round. Therefore, the effects of the soil drying treatment on lowland poorly drained paddy field by any drainage are highly significant for the satisfactory production of rice crops. Kobo0 has noted that, among the numerous soil properties changed after drainage of the lowland poorly drained paddy field, the decreases in soil nitrogen level which will be characterized by the stabilization of soil humus are associated most closely with the promotion of the soil productivity. The present study was set up to ascertain the effects of soil drying by underdrainage of the lowland poorly drained paddy field incomparison with the better drained paddy field under cultivation.  相似文献   

A novel fractionation technique of humic acid using a resinous ion exchanger     

Ryosuke Shiroya  Kyoichi Kumada 《Soil Science and Plant Nutrition》2013,59(3):317-320

The purpose of this study was to fractionate humic acid by using a resinous ion exchanger containing a complex metal ion.  相似文献   

Contrasting effect of perlecan on adipogenic and osteogenic differentiation of mesenchymal stem cells in vitro     

Ryosuke Nakamura  Fumio Nakamura  Shigeharu Fukunaga 《Animal Science Journal》2014,85(3):262-270

Perlecan, a basement membrane component, shows diverse functions in different organs and tissues. However, the role of perlecan in differentiation of mesenchymal stem cells (MSCs) has been barely investigated. In this study, we examined the effect of perlecan on adipogenic and osteogenic differentiation of MSCs in vitro by adding extrinsic perlecan to culture media or blocking the function of intrinsic perlecan expressed into culture media by differentiating MSCs. Extrinsic perlecan suppressed adipogenic differentiation; however, it promoted osteogenic differentiation. These functions were further confirmed by a study of blocking intrinsic perlecan. Perlecan treated with heparitinase‐I also showed the suppressive effect on adipogenic differentiation. In contrast, the promotive effect on osteogenic differentiation was found to be heparan sulfate‐dependent. Intrinsic perlecan was suggested to be effective at the late stage of adipogenic differentiation by a study of perlecan‐blocking performed at distinct periods, but was suggested to be effective at the early stage of osteogenic differentiation. Our results showed perlecan has contrasting effect on adipogenic and osteogenic differentiation of MSCs due to its diverse actions. Based on these outcomes, we recognized that employing extrinsic perlecan or blocking intrinsic perlecan is effective for regulating adipogenic and osteogenic differentiation of MSCs by restricting its direction.  相似文献   

Glomerular filtration rate in cows estimated by a prediction formula     

Isao Murayama  Anna Miyano  Tsubasa Sato  Ryosuke Iwama  Hiroshi Satoh  Toshihiro Ichijyo  Shigeru Sato  Kazuhisa Furuhama 《Animal Science Journal》2014,85(12):1001-1004

To testify the relevance of Jacobsson's equation for estimating bovine glomerular filtration rate (GFR), we prepared an integrated formula based on its equation using clinically healthy dairy (n = 99) and beef (n = 63) cows, and cows with reduced renal function (n = 15). The isotonic, nonionic, contrast medium iodixanol was utilized as a test tracer. The GFR values estimated from the integrated formula were well consistent with those from the standard multisample method in each cow strain, and the Holstein equation prepared by a single blood sample in Holstein dairy cows. The basal reference GFR value in healthy dairy cows was significantly higher than that in healthy beef cows, presumably due to a breed difference or physiological state difference. It is concluded that the validity for the application of Jacobsson's equation to estimate bovine GFR is proven and it can be used in bovine practices.  相似文献   

The electrical conductivity of post-perovskite in Earth's D' layer     

Ohta K  Onoda S  Hirose K  Sinmyo R  Shimizu K  Sata N  Ohishi Y  Yasuhara A 《Science (New York, N.Y.)》2008,320(5872):89-91

Recent discovery of a phase transition from perovskite to post-perovskite suggests that the physical properties of Earth's lowermost mantle, called the D' layer, may be different from those of the overlying mantle. We report that the electrical conductivity of (Mg0.9Fe0.1)SiO3 post-perovskite is >10(2) siemens per meter and does not vary greatly with temperature at the conditions of the D' layer. A post-perovskite layer above the core-mantle boundary would, by electromagnetic coupling, enhance the exchange of angular momentum between the fluid core and the solid mantle, which can explain the observed changes in the length of a day on decadal time scales. Heterogeneity in the conductivity of the lowermost mantle is likely to depend on changes in chemistry of the boundary region, not fluctuations in temperature.  相似文献   

Nocturnality in dinosaurs inferred from scleral ring and orbit morphology     

Schmitz L  Motani R 《Science (New York, N.Y.)》2011,332(6030):705-708

Variation in daily activity patterns facilitates temporal partitioning of habitat and resources among species. Knowledge of temporal niche partitioning in paleobiological systems has been limited by the difficulty of obtaining reliable information about activity patterns from fossils. On the basis of an analysis of scleral ring and orbit morphology in 33 archosaurs, including dinosaurs and pterosaurs, we show that the eyes of Mesozoic archosaurs were adapted to all major types of diel activity (that is, nocturnal, diurnal, and cathemeral) and provide concrete evidence of temporal niche partitioning in the Mesozoic. Similar to extant amniotes, flyers were predominantly diurnal; terrestrial predators, at least partially, nocturnal; and large herbivores, cathemeral. These similarities suggest that ecology drives the evolution of diel activity patterns.  相似文献   

Viral-derived DNA invasion and individual variation in an Indonesian population of large flying fox Pteropus vampyrus     

Atsuo IIDA  Hitoshi TAKEMAE  Ronald TARIGAN  Ryosuke KOBAYASHI  Hirokazu KATO  Hiroshi SHIMODA  Tsutomu OMATSU  Supratikno  Chaerul BASRI  Ni Luh Putu Ika MAYASARI  Srihadi AGUNGPRIYONO  Ken MAEDA  Tetsuya MIZUTANI  Eiichi HONDO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1068

Here, we performed next-generation sequencing (NGS) on six large flying foxes (Pteropus vampyrus) collected in Indonesia. Seventy-five virus species in the liver tissue of each specimen were listed. Viral homologous sequences in the bat genome were identified from the listed viruses. This finding provides collateral evidence of viral endogenization into the host genome. We found that two of the six specimens bore partial sequences that were homologous to the plant pathogens Geminiviridae and Luteoviridae. These sequences were absent in the P. vampyrus chromosomal sequences. Hence, plant viral homologous sequences were localized to the hepatocytes as extrachromosomal DNA fragments. Therefore, this suggests that the bat is a potential carrier or vector of plant viruses. The present investigation on wild animals offered novel perspectives on viral invasion, variation, and host interaction.  相似文献   

Spawning induction of blue mackerel <Emphasis Type="Italic">Scomber australasicus</Emphasis> and eastern little tuna <Emphasis Type="Italic">Euthynnus affinis</Emphasis> by oral administration of a crude gonadotropin-releasing hormone analogue     

Kotaro Amezawa  Ryosuke Yazawa  Yutaka Takeuchi  Goro Yoshizaki 《Fisheries Science》2018,84(3):495-504

Scombridae species, such as tunas and mackerels, often do not spawn in land-based fish tanks without hormone treatment. To induce spawning in various fishes, a gonadotropin-releasing hormone analogue (GnRHa) is often administered by pellet implantation. Noninvasive administration is desired to induce spawning in scombrids that are sensitive to handling stress. Spawning induction by oral administration has been reported in several fishes, yet this method has not been put into practice in the aquaculture industry since a considerable amount of GnRHa is needed. Utilization of peptide synthesizers is widespread, and antigen-grade GnRHa (AgGnRHa) produced by a custom-peptide supplier is approximately 100-fold cheaper than conventional reagent-grade GnRHa (RgGnRHa), although the purity of AgGnRHa is lower. Here, we confirmed that the spawning induction potency of AgGnRHa was similar to that of RgGnRHa by pellet implantation in blue mackerel Scomber australasicus. Oral administration of AgGnRHa [6.0 mg/kg body weight (BW) per day] showed an equivalent ability to induce spawning of the mackerel as pellet implantation (0.1 mg/kg BW). We could also induce spawning of eastern little tuna Euthynnus affinis by oral administration of the AgGnRHa. Further, the obtained eggs showed higher survival. Thus, the oral delivery of AgGnRHa could be a powerful tool to induce spawning in Scombridae.  相似文献