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11.
Takishita Kiyotaka Kawai Rihoko Tsutsumi Ayaka Tanifuji Goro Otsubo Mayuko 《Fisheries Science》2020,86(4):633-643
Fisheries Science - Tidal flats are ecologically important as they support a large community of animals (e.g., crabs, mollusks, and polychaetes) and restore water quality. However, information... 相似文献
12.
We report that in a leaf insect, Phyllium westwoodii Wood-Mason (Phasmatodea: Phylliidae), two differing apertures can be used for oviposition, the color of eggs being affected by which aperture is used. Eggs which are forcibly propelled from the internal space within the valvulae of the abdomen are brown, whereas white eggs emerge slowly from the opening between the eighth sternite and the valvulae, and are deposited close to the ventral surface of the female. This unusual oviposition system does not appear to have been previously reported in phasmatids or in other insects. 相似文献
13.
Kana Yamashita Yasuhiko Hirakawa Hiroshi Nakatani Motoyoshi Ikeda 《Journal of Wood Science》2009,55(3):161-168
The transverse shrinkage variation within trees was examined for five sugi cultivars. The within-tree trends of tangential
shrinkage (α
T) were different by cultivar, whereas radial shrinkage (α
R) increased from pith to bark in most cultivars. The tangential/radial shrinkage ratio (α
T/α
R) decreased from pith to bark in most cultivars, because the radial variation of α
R was larger than that of α
T. The cultivars showed significant differences among cultivars in α
T, α
R, and α
T/α
R, but the difference among cultivars for α
T/α
R was smaller. The relationships between transverse shrinkage and microfi bril angle (MFA), basic density (BD), tree ring parameters,
and modulus of elasticity were examined. The α
T and α
R showed positive relationships with BD, latewood percentage, latewood density, and modulus of elasticity, and negative relationships
with MFA and ring width. The relationships with earlywood density were weak. Sugi exhibited variation in transverse shrinkage
within stem and among cultivars, with the variation affected by MFA, density, and tree ring parameters.
Part of this article was presented at the 56th Annual Meeting of the Japan Wood Research Society, Akita, Japan, August 2006,
and the 57th Annual Meeting of the Japan Wood Research Society, Hiroshima, Japan, August 2007 相似文献
14.
Machiko Yamada Mayuko Otsubo Yuki Tsutsumi Chiaki Mizota Naoki Iida Kazuma Okamura Masashi Kodama Akira Umehara 《Fisheries Science》2013,79(6):923-934
The genus Skeletonema includes phytoplankton species that are important primary producers in marine food chains. Brackish waters have been reported to be one of the important habitats of some species of Skeletonema. To elucidate the species diversity of Skeletonema in brackish waters, we investigated three Japanese brackish bodies of water: the coastal waters of Toyama Bay, a tidal area of the Chikugo River, and a constructed reservoir in Isahaya Bay. We used molecular analysis based on large subunit rDNA and fine morphological structure to identify species. Skeletonema costatum s.s. (sensu stricto) was isolated at salinities as low as 0.6, but Skeletonema dohrnii, Skeletonema subsalsum, and Skeletonema tropicum were not found at salinities below 11.0. S. costatum s.s. could survive transfer from a medium with a salinity of 15 to a salinity of 2, but S. dohrnii did not survive in the same experiment. Only S. costatum s.s. germinated from the sediment of a reservoir in which the salinity was 0.1–1.4; incubation conditions included temperatures of 10, 15, 20, 25, and 30 °C and salinities of 5 and 30. Skeletonema costatum s.s. was identified as the species most adaptable to low-level salinity variations throughout its lifecycle. 相似文献
15.
Cloned porcine embryos can maintain developmental ability after cryopreservation at the morula stage
Nakano K Matsunari H Nakayama N Ogawa B Kurome M Takahashi M Matsumoto M Murakami H Kaji Y Nagashima H 《The Journal of reproduction and development》2011,57(2):312-316
The aim of the present study was to clarify the overall efficiency of porcine somatic cell nuclear transfer (SCNT) by incorporating cryopreservation of the cloned embryos before transfer. The SCNT embryos reconstructed with preadipocytes and in vitro-matured (IVM) oocytes were cultured to harvest morula stage embryos; they were then subjected to delipation (removal of cytoplasmic lipid droplets) and vitrification. After warming and culture, the embryos developing to blastocysts were transferred to recipients to obtain cloned piglets. From 372 reconstructed embryos, 188 (50.5%) reached the morula stage and 117 (31.5%) developed to blastocysts after vitrification. Transfer of 98 (26.3%) morphologically normal blastocysts gave rise to 6 (1.6%) piglets, including 1 stillborn. The efficiency of the cloned piglet production was comparable with that obtained using SCNT embryos without cryopreservation (2.7%, 17/635). Here, we demonstrate that porcine somatic cell cloning can be performed without a significant reduction in efficiency even when the SCNT embryos are cryopreserved before transfer. 相似文献
16.
Bovine mastitis is typically caused by microbial infection of the udder, but the factors responsible for this condition are varied. One potential cause is the milking system, and although previous studies have investigated various methods for inspecting these devices, most have not assessed methods for evaluating the milking units. With this in mind, we analyzed the factors that affect the vacuum inside the milking claw by using a simulated milking device and by measuring milking claw vacuum when adjusting the flow rate in five stages. The factors analyzed in each milking system were the vacuum pressure settings (high and low line system) , milk tube length (200‐328 cm), aperture diameter (14‐22.2 mm), constricted aperture diameter (12 mm), tubing configurations, lift formation (0‐80 cm), claw type (bottom and top flow) and use or non‐use of a milk sampler. The study findings demonstrated that all of these variables had a significant impact on claw vacuum and suggest that a diagnostic method using a simulated milking device should be considered when inspecting modern milking systems. 相似文献
17.
Koreishi M Zhang D Imanaka H Imamura K Adachi S Matsuno R Nakanishi K 《Journal of agricultural and food chemistry》2006,54(1):72-78
A novel enzyme that catalyzes efficient hydrolysis of capsaicin (8-methyl-N-vanillyl-6-nonenamide) was isolated from the culture broth of Streptomyces mobaraensis. The enzyme consisted of two dissimilar subunits with molecular masses of 61 and 19 kDa. The enzyme was activated and stabilized in the presence of Co2+. It showed a pH optimum of about 8 and was stable at temperatures of up to 55 degrees C for 1 h at pH 7.8. The specific activity of the enzyme for the hydrolysis of capsaicin was 10(2)-10(4) times higher than those for the enzymes reported to date. In an aqueous/n-hexane biphasic system, capsaicin analogues such as octanoyl, decanoyl, and lauroyl vanillylamides were synthesized from the corresponding fatty acids and vanillylamine at yields of 50% or greater. In addition, the enzyme catalyzed the deacylation of N-lauroyl-L-amino acids and N-lauroyl-L-dipeptides and the efficient synthesis of Nalpha-lauroyl-L-lysine, Nepsilon-lauroyl-L-lysine, and various N-lauroyl-peptides in aqueous solution in both the absence and the presence of glycerol. 相似文献
18.
19.
Kusuhara H Hohdatsu T Okumura M Sato K Suzuki Y Motokawa K Gemma T Watanabe R Huang C Arai S Koyama H 《Veterinary microbiology》2005,108(3-4):155-165
Fel-O-Vax FIV is a dual-subtype vaccine consisting of inactivated whole viruses of subtype A (Petaluma strain) and subtype D (Shizuoka strain). The efficacy of this vaccine against heterologous subtype A strain challenge was demonstrated, but it is unclear whether the result reflects efficacy in the field. In this study, we evaluated the efficacy of this vaccine against contact challenge by exposing both vaccinated and unvaccinated control animals with cats infected with Aomori-2 strain belonging to subtype B, a subtype prevalent in many regions of the world. Nineteen specific-pathogen-free (SPF) cats were divided into a vaccinated group (six cats), an unvaccinated control group (eight cats), and a challenge group (five cats), and maintained in the same room. Cats were monitored for FIV proviral DNA by nested PCR and for FIV-specific antibody levels by ELISA. After 1 year of commingling, each cat in the vaccinated group was given a booster dose. In addition, the original challenge group was removed and replaced with another challenge group of SPF cats, which were inoculated with the Aomori-2 strain. FIV infection was confirmed in four of the eight animals in the unvaccinated control group by the 29th week in the second year of commingling. In contrast, all of the animals were negative in the vaccinated group. These findings confirmed the efficacy of this vaccine against heterologous stains classified as subtype B, and suggested that the vaccine exhibits broad efficacy against genetically diverse FIV. 相似文献
20.
Ueno S Kurome M Ueda H Tomii R Hiruma K Nagashima H 《The Journal of reproduction and development》2005,51(3):405-410
Incomplete cytoplasmic maturation of in vitro matured (IVM) oocytes has been known to cause microtubule and microfilament alterations, which may result in abnormal pronuclear formation and failed embryonic development. We examined the influences of maturation conditions on meiotic spindle morphology at metaphase of meiosis II (MII) in porcine oocytes. Porcine oocytes were matured under various conditions, i.e., in vitro or in vivo, with different amounts of cumulus cells, with or without hormonal supplements, and with various exposure durations to the hormones, to examine the effects on spindle morphology in MII oocytes by immunofluorescence under confocal laser microscopy. Interpolar spindle length (microm) and spindle area (microm2) were compared among these maturation conditions. The spindle length was significantly shorter in IVM oocytes compared to those matured in vivo. Oocytes collected from cumulus oocyte complexes (COCs), which were poor in cumulus cells, showed smaller spindle areas than those from cumulus-rich COCs. The spindle length and area were both significantly reduced in oocytes grown without hormonal supplements. When oocytes were grown with hormonal supplements for either 6 or 22 hours for the first half of culture, there was no difference in the spindle morphology between these oocytes. These results suggested that maturation conditions significantly influence morphogenesis of MII spindles in porcine oocytes. Oocytes matured in poor conditions were more likely to have a shorter spindle length (long axis) and smaller spindle areas. 相似文献