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101.
Yosuke Yanai Tomoyoshi Hirota Manabu Nemoto Nobuhisa Koga 《Soil biology & biochemistry》2011,43(9):1779-1786
It has been suggested that soil-thawing and snow-melting are critical triggers for vigorous emissions of nitrous oxide (N2O) from soils in cold regions. However, because soil freezing is affected by air temperature and snow cover, accurate predictions that estimate subsequent emissions of this important greenhouse gas are difficult to make. In this study, we measured in situ soil gas N2O and oxygen (O2) concentrations at two experimental sites in northern Japan over the period of a year, from November 2008 to October 2009, to clarify the factors stimulating N2O production in soil at low temperatures. The sites were N-fertilized bare arable lands with different soil frost depths and snowmelt rates, according to the snow cover management imposed. Winter-to-spring net N2O fluxes, ranging from −0.10 to 1.95 kg N2O-N ha−1, were positively correlated with the annual maximum soil frost depth (ranging from 0.03 to 0.41 m; r = 0.951***). In the plots with deeper maximum soil frost, winter-to-spring N2O fluxes represented 58% to 85% of the annual values. Soil N2O production was stimulated when the soil frost depth was greater than 0.15 m or the daily mean soil temperature at 0.05-m depth was below −2.0 °C. In the soil with the greatest frost depth, soil gas N2O concentrations at the depth of 0.10 m peaked at 46 ppm when soil gas O2 concentrations fell down to 0.12 m3 m−3 under soil temperature below 0.0 °C. Snowmelt acceleration had no stimulating effect on N2O production in the soil during the winter-to-spring period. 相似文献
102.
This review describes the study of freeze-dried mouse sperm for practical application in preserving and transporting genetic resources. Freeze-dried sperm can be used to preserve and transport genetic resources; however, there still remain many areas which need to be studied. In particular, it is essential to assure long-term preservation over several decades or centuries. Recently, the theory of accelerated degradation kinetics to freeze-dried mouse sperm has been applied, and found that long-term preservation by conventional methods requires temperatures lower than -80 C. When the relationship between the pressure at primary drying and the preservation potential of freeze-dried mouse sperm was examined, a pressure of 0.37 mbar at primary drying significantly improved the developmental rate to the blastocyst stage. In addition, it has been shown that freeze-dried sperm stored at -80 C with and without transportation can retain their ability to generate viable offspring after storage for up to 2 years. Sperm chromatin structure assay (SCSA) was applied to mouse sperm freeze-dried under several conditions and compared the results with the embryonic developmental rates of freeze-dried sperm after intracytoplasmic sperm injection (ICSI) and with comet assay results. Furthermore, SCSA might be useful for estimation of developmental potential of fertilized eggs derived from ICSI using freeze-dried sperm in mice. 相似文献
103.
Yosuke Amagai Akane Tanaka Kyungsook Jung Akira Matsuda Kumiko Oida Sho Nishikawa Hyosun Jang Saori Ishizaka Hiroshi Matsuda 《Research in veterinary science》2014
Mast cell tumor (MCT) is the most common cutaneous tumor in dogs. We recently revealed that production of stem cell factor (SCF) contributes to the proliferation of neoplastic mast cells in an autocrine/paracrine manner. The aim of the present study was to determine the contribution of the mechanism in clinical MCTs. In consequence, high SCF expression (>10 times compared to HRMC cells) was observed in 5 of 7 MCT samples used in the study regardless of KIT mutation, which was confirmed in immunohistochemical analysis. In addition, production of SCF was observed in Ki-67-positive cells in the MCT xenograft. These results indicate the broad contribution of SCF autocrine/paracrine mechanism on clinical MCTs, providing the rationale for the clinical use of KIT inhibitors regardless of KIT mutation. 相似文献
104.
Kanomata Yohei Hayakawa Ryo Kashikura Jun Satoh Kosuke Matsuhira Hiroaki Kuroda Yosuke Kitazaki Kazuyoshi Kubo Tomohiko 《Genetic Resources and Crop Evolution》2022,69(1):271-283
Genetic Resources and Crop Evolution - Garden beet is the ancestor of fodder beets and sugar beets, but the origin of garden beet’s genetic potential to evolve novel beet types is debatable.... 相似文献
105.
Tomoaki Takahashi Kazukiyo Yamamoto Yosuke Miyachi Yoshimichi Senda Masashi Tsuzuku 《Journal of Forest Research》2006,11(2):117-123
Penetration rates of laser pulses transmitted from a small-footprint airborne light detection and ranging (LiDAR) system in
closed-canopy, middle-aged (40–50 years old) hinoki cypress (Chamaecyparis obtusa Sieb. et Zucc.) and sugi (Cryptomeria japonica D. Don) plantations that had similar levels of canopy openness were studied. The number of transmitted pulses was 107 427
points/ha for the hinoki cypress stand and 122 883 points/ha for the sugi stand. The penetration rates of the first (Pf) and second pulses (Ps) that reached the ground were 0.1% and 1.0% in the hinoki cypress stand, and 2.6% and 5.5% in the sugi stand, respectively.
Penetration rates for the total number of pulses (Pf+s) that reached the ground within each stand were 1.1% and 8.1%, respectively, and values for Pf+s, Pf, and Ps for sugi and hinoki cypress stands were significantly different (P < 0.001). The results of this study indicated that the generation of accurate digital terrain models in dense hinoki cypress
stands with complex topographies using only the data from laser pulses with poor laser penetration rates is likely to be difficult. 相似文献
106.
Ken-ichiro Yamashita Yukiya Hisatsune Toyohusa Sakamoto Kazuhiro Ishizuka Yosuke Tashiro 《Euphytica》2002,125(2):163-167
Chromosomes and cytoplasms were analyzed in two lines of a somatic hybrid between onion (Allium cepa L.) and garlic (A. sativum L.). One line of the somatic hybrid had 40 chromosomes and the other 41chromosomes. Genomic in situhybridization successfully revealed the chromosome constitution of the two lines. One line had 20 chromosomes from onion and17
chromosomes from garlic, and the other had 21 chromosomes from onion and 17chromosomes from garlic. Interestingly, both lines
had three chimeric chromosomes. PCR-RFLP analyses of chloroplast and mitochondrial DNAs of both lines showed that these were
identical to the onion parent.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
107.
The induction of haploid plants from F1 hybrids between CMS shallot with Allium galanthum cytoplasm and common onion was examined. Starting with 535 unpollinated flowers cultured in B5 medium 25 seedlings from part
henogenetic embryos were obtained of which 13 seedlings survived. Eleven seedlings were determined as haploid plants (2n = x = 8) and 2 seedlings were doubled haploid plants (2n = 2x = 16). All haploid and doubled haploid plants preserved chloroplast DNA (cpDNA) and mitochondrial DNA (mtDNA) from A. galanthum. Segregation in different characters was observed among the haploid plants. The haploid and doubled haploid plants exhibited
the different combinations of genes from shallot and common onion. Crossing of the doubled haploid plants with other shallot
strains, common onion cultivars or related species may produce excellent F1 hybrids for bulb production.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
108.
109.
Katsube T Tabata H Ohta Y Yamasaki Y Anuurad E Shiwaku K Yamane Y 《Journal of agricultural and food chemistry》2004,52(8):2391-2396
Oxidation of low-density lipoprotein (LDL) has been implicated in atherogenesis. Antioxidants that prevent LDL from oxidizing may reduce atherosclerosis. This study investigated LDL antioxidant activity in edible plant products for development of dietary supplementation to prevent atherosclerosis. Fifty-two kinds of edible plants were extracted using 70% aqueous ethanol solution, and the antioxidant activity of the extracts, which inhibit human LDL oxidation induced by copper ion, was determined on the basis of the oxidation lag time and represented as epigallocatechin 3-gallate equivalent. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and total phenolic content were also measured for comparisons with antioxidant activity in LDL. Plant products showing the greatest activity in LDL oxidation assay were akamegashiwa (Mallotus japonicus) leaf, Japanese privet (Ligustrum japonicum) leaf, green tea [Camellia sinensis (L.) O. Kuntze], and astringent persimmon (Diospyros kaki). The present study revealed high levels of LDL antioxidant activity in plant products for which such activity levels are underestimated in the DPPH radical scavenging assay and Folin-Ciocalteu assay. 相似文献
110.
Yosuke Kadomae Yasuhide Maruyama Masataka Sugimoto Takashi Taniguchi Kiyohito Koyama 《Fibers and Polymers》2009,10(3):275-279
Electrospun atactic polypropylene (PP) fibers are thicker than those obtained from isotactic PP, although the viscosity of
molten PPs is almost same. Thus we focused on the effect of tacticity of PP on fiber diameters. The PP samples with various
tacticity were prepared by changing the blend ratio of isotactic PP and atactic PP. Melt-electrospinning is performed by using
blended samples, and then electrospun fibers were observed by scanning electron microscope to evaluate fiber diameter of obtained
fibers. It is clear that the diameter of electrospun PP fibers decreases as high tacticity content of PP increases. This result
suggests that tacticity of samples is an important factor to control the electrospun fiber diameter. 相似文献