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51.
This study aimed to develop a water-extraction system which could produce the fresh water from the air in arid regions and which used renewable energies as the electric power source. In this paper, the experiments for water extraction from the air were carried out by using the novel multi-stage water-extraction device with Peltier deices for two cases of temperature and related humidity of the air. One was the case where the temperature and the related humidity of the air were constant, and the other was the case where they were simulated the variation of the temperature and related humidity of the air in a day of summer and spring in Loess Plateau, China. The effects of the temperature and related humidity of the atmospheric air and supply the electric power to Peltier devices on performance of water production of the device were investigated and reported. 相似文献
52.
Takeshi Kashiwa Keigo Inami Masashi Fujinaga Hideki Ogiso Takanobu Yoshida Tohru Teraoka Tsutomu Arie 《Journal of General Plant Pathology》2013,79(6):412-421
Six4, a small protein secreted by Fusarium oxysporum f. sp. lycopersici (Fol) in tomato xylem sap during infection, triggers Fol race 1-specific resistance (I) in tomato. SIX4 is regarded as an avirulence gene. Although SIX4 is considered unique to Fol race 1, we detected this gene in the cabbage yellows fungus F. oxysporum f. sp. conglutinans (Foc) by PCR. Because the genes from Foc and SIX4 in Fol were >99 % identical at the nucleotide level, the Foc gene was designated FocSIX4. The expression of FocSIX4 was detected by RT-PCR in stems and roots of cabbage 8 days after infection with Foc. In contrast with Fol, disruption of FocSIX4 in Foc did not increase virulence to Foc-resistant cabbage cvs. Shutoku-SP and Koikaze. On the contrary, the disruptants had reduced virulence not only on Foc-resistant cultivars but also on Foc-susceptible cv. Shikidori. These results suggested that FocSIX4 is involved in virulence, but not in avirulence, in the cabbage yellows fungus. 相似文献
53.
Takayuki Arazoe Shuichi Ohsato Tsutomu Arie Katsuyoshi Yoneyama Shigeru Kuwata 《Journal of General Plant Pathology》2013,79(6):422-430
To investigate mitotic homologous recombination (HR) in Pyricularia oryzae, we created an HR detection system. The system consists of two non-functional enhanced yellow fluorescent protein (YFP) and blasticidin S deaminase (BSD) fusion genes (YFP::BSD). If mitotic HR occurs between the two non-functional genes in the genome, restoration of the functional YFP::BSD gene can be expected. The expression of the functional YFP::BSD gene can be detected by both YFP fluorescence and resistance against BS. When the P. oryzae genome was transformed simultaneously with two non-functional genes, all six lines of transformants with both genes had some portion of their hyphae exhibiting YFP fluorescence and BS resistance during growth. Up to ca. 10 % of conidia harvested from the mycelium of each of the six lines had YFP fluorescence, suggesting that HR consistently occurs during mycelium growth. To determine whether and how the HR-mediated phenotypic changes occurred at the DNA level, we analyzed the genomic DNA of BS-resistant mycelia by PCR-RFLP and sequencing and were able to confirm the existence of a restored functional YFP::BSD gene and a non-functional recombinant gene. Collectively, these findings demonstrate that we established a successful HR detection system for P. oryzae, which can be used for other plant pathogens, and that mitotic HR actually occurs in P. oryzae and constitute the first experimental evidence for mitotic HR in a fungus. 相似文献
54.
Dung Viet Pham Munehide Ishiguro Ha Thu Thi Tran Tsutomu Sato 《Soil Science and Plant Nutrition》2013,59(3):356-366
AbstractSoil dispersion induces soil erosion and colloidal leaching. Nutrients are lost at the same time and this causes water contamination. Phosphate is an essential element for living organisms. Because phosphate influences soil dispersion and it is an important limited resource, this influence must be evaluated well in order to diminish negative effects on soil structure. In this paper, we firstly evaluated the influence of phosphate sorption on soil dispersion by calculating repulsive potential energy between soil particles. Ferralsol, which is a typical soil in rainy tropical regions, was used as the material. The dispersion-flocculation phenomena were investigated with absorbance of soil suspension under different pH, phosphate adsorption and electrolyte concentration in an Na-NO3-PO4 system. The repulsive potential energy was calculated based on the diffuse double layer theory and the measured zeta potential. We indicated that the measured absorbance increased with the increase of the repulsive potential energy. The repulsive potential energy increased with increasing phosphate sorption up to about 5 to 20 mmol kg?1 at all pH, and it induced the soil dispersion, because phosphate sorption increased the negative charge of the soil. After its peak, it decreased with increasing phosphate sorption because the electrolyte concentration increased and the electrolyte screened the electric field near the soil surface. The repulsive potential energy also increased with increasing pH because of the increase of the negative charge of the soil. Even at low pH, after a certain amount of phosphate sorption, the soil dispersed due to the increase of repulsive potential energy, although the soil flocculated before phosphate application. Because the soil dispersion causes soil and phosphorus loss, the influence of soil pH and phosphate sorption on the soil dispersion should be considered for good soil management. 相似文献
55.
Koichiro Hiura Tsutomu Hattori Choseki Furusaka 《Soil Science and Plant Nutrition》2013,59(4):459-465
In this report we studied the effects of mechanical grinding of paddy soils on nitrogen mineralization and bacterial number when soils were incubated under a submerged condition after grinding. Nitrogen mineralization was increased by grinding soil samples as compared with those without grinding. The value of (Nd-Nu)/Nu, where Nd is the amount of ammonia-nitrogen formed by incubation of disrupted samples and Nu those of the undisrupted soils, was in good correlation with clay/humus ratio. Although significant difference was not observed between the number of aerobic bacteria with undisrupted and disrupted soil samples, higher anaerobic bacterial numbers were found with disrupted than with undisrupted ones. A significant correlation was also obtained between the amounts of nitrogen mineralization increased by the grinding of soil and the numbers of anaerobic bacteria. 相似文献
56.
Takafumi Inoue Tsutomu Enoki Naoaki Tashiro Kotaro Sakuta Susumu Inoue 《Journal of Forest Research》2008,13(6):365-371
We investigated factors affecting the distribution of naturally regenerated broad-leaved trees in a 140-year-old Cryptomeria japonica plantation. We used path analysis to examine the relationship among microtopography, the biomass of planted trees, and the
biomasses of canopy and subcanopy trees of broad-leaved species. The study plot was divided into three topographic types (ridge,
slope, and valley), and we discuss how the different topographic types are affected. For all topographic types, the biomass
of canopy trees of broad-leaved species decreased with convexity. For slope and valley topographies, the biomass of subcanopy
trees of broad-leaved species also decreased with convexity. For ridge topography, the biomass of subcanopy trees of broad-leaved
species increased with the biomass of planted trees, and decreased with the biomass of canopy trees of broad-leaved species.
These results suggest the effects of microtopography on the biomass of subcanopy trees were much larger than the effects of
canopy trees for slope and valley topographies, while the effects of microtopography were smaller for ridge topography. 相似文献
57.
Annual amounts of litterfall and nitrogen input by litterfall were measured in a subtropical evergreen broad-leaved forest
to examine the contribution of a liana species, Mucuna macrocarpa Wall., to the spatial heterogeneity of litterfall production and nitrogen input. The total litterfall in the study plot was
7.1 t ha−1 year−1. The amount of litterfall varied with topography and was greatest at the valley bottom and decreased toward the ridges. Macuna macrocarpa litterfall was absent on the ridges although it accounted for the largest percentage, 32%, of total leaf litter production
in the valley. Nitrogen input by litterfall was 69 kg ha−1 year−1 in the plot. Nitrogen input by litterfall was also largest at the valley bottom and decreased toward the ridges. Leaf litter
of M. macrocarpa had approximately twice the nitrogen concentration of litterfall of other species. Macuna macrocarpa accounted for 42% of nitrogen input by leaf litter in the valley. The abundance and the high nitrogen concentration of M. macrocarpa intensified differences in the amount of litterfall and nitrogen input by litterfall between valleys and ridges. It was concluded
that a liana species, M. macrocarpa, can contribute to the spatial heterogeneity of litterfall and may subsequently affect nutrient cycling in a subtropical
evergreen broad-leaved forest on Okinawa Island. 相似文献
58.
Ban Masatoshi Hida Kazuhiro Kuwaki Motoyasu Horanai Tetsuo Ohnuki Tsutomu Oseko Norihisa 《Fisheries Science》2023,89(1):31-40
Fisheries Science - Blue sac disease (BSD) in salmonids results in the abnormal accumulation of ascites fluid and can often lead to mass mortality. However, the symptoms and causes of BSD remain... 相似文献
59.
Tsutomu Yagihashi Mitsuhiro Hayashida Toshizumi Miyamoto 《Journal of Forest Research》2000,5(3):213-215
To evaluate what prevents seed germination and why ingestion by birds enhances germination, we carried out germination experiments
using bird-dispersed seeds of twoPrunus species (Prunus sargentii andP. ssiori) in the laboratory. Germination of seeds with following four treatments was compared: “Ingested seeds” excreted after feeding
of fruits to birds; “Extracted seeds” deliberately extracted from the fruit pulp; “Juiced seeds” which were supplemented with
the juice of the pulp after seeds had been deliberately extracted from the pulp; and “Intact seeds” in untreated whole fruits.
Many ingested (27%, 23% inP. sargentii, 18% inP. ssiori) and extracted seeds (24% inP. sargentii, 17% inP. ssiori) germinated, and difference in germination percentages between ingested and extracted seeds were not significant, for eitherPrunus species. The Juiced seeds rarely germinated (2% inP. sargentii, 6% inP. ssiori), and seeds within intact fruits did not germinate. These results suggest that the fruit pulp and the juice of the pulp inhibit
germination and the seeds could germinate without ingestion by birds once they had been manually extracted from pulp. Therefore,
it is considered that bird ingestion enahnces germination by removing pulp, especially juice of the pulp, in these twoPrunus species. 相似文献
60.
Tsutomu Suzuki Kyoko Suzuki Yukio Takahashi Mitsuhiro Okimoto Tetsuo Yamada Noriyasu Okazaki Yuichi Shimizu Masashi Fujiwara 《Journal of Wood Science》2007,53(1):54-60
Japanese larch wood loaded with nickel (1%–4%) alone or with nickel and calcium (0.25%–1.5%) was carbonized at 800°–900°C
for 0–120min with a heating rate of 5°–20°C min−1 in a helium flow of 5.8−46.4 ml STP cm−2 min−1 to examine the influence of these variables on the crystallization of carbon (the formation of T component) and the development
of mesoporosity. From the obtained results, reaction conditions suitable for effective production of carbon with the dual
functions of adequate electroconductivity and adsorption capacity in liquid phase were established, thereby explaining the
factors that govern the process. It was also confirmed that mesopore having a diameter of about 4 nm was selectively produced
at the cost of specific (BET) surface area in parallel with the formation of T component. This result provided good insight
into how the simultaneous dual function could be realized. 相似文献