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Nagata T Koyanagi M Tsukamoto H Saeki S Isono K Shichida Y Tokunaga F Kinoshita M Arikawa K Terakita A 《Science (New York, N.Y.)》2012,335(6067):469-471
The principal eyes of jumping spiders have a unique retina with four tiered photoreceptor layers, on each of which light of different wavelengths is focused by a lens with appreciable chromatic aberration. We found that all photoreceptors in both the deepest and second-deepest layers contain a green-sensitive visual pigment, although green light is only focused on the deepest layer. This mismatch indicates that the second-deepest layer always receives defocused images, which contain depth information of the scene in optical theory. Behavioral experiments revealed that depth perception in the spider was affected by the wavelength of the illuminating light, which affects the amount of defocus in the images resulting from chromatic aberration. Therefore, we propose a depth perception mechanism based on how much the retinal image is defocused. 相似文献
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Responses of community structure,diversity, and abundance of understory plants and insect assemblages to thinning in plantations 总被引:1,自引:0,他引:1
Hisatomo Taki Takenari Inoue Hiroshi Tanaka Hiroshi Makihara Masahiro Sueyoshi Masahiro Isono Kimiko Okabe 《Forest Ecology and Management》2010
Identifying effective management operations for plantations is important for conservation of biodiversity in a plantation-dominated landscape. We tested whether pre-commercial thinning influenced community structures and could be an effective strategy for increasing diversity and abundance of plants and animals in plantations. We designated thinned and unthinned study stands in Japanese cedar (Cryptomeria japonica) plantations and compared the communities of understory vegetation, bees, butterflies, hoverflies, and longhorn beetles 1 and 3 years after thinning. The analyses of vegetation showed that pre-commercial thinning affected community structure, but species richness and vegetation abundance were not significantly affected. Thinning affected insect community structure, and both species richness and abundance of all insect groups increased 1 year after thinning. However, 3 years after thinning, significant differences only remained in the species richness of bees and the abundance of bees, butterflies, and hoverflies. These results suggest that pre-commercial thinning in plantation stands influences the community structure of understory vegetation and can be an effective way to increase the diversity and abundance of some insect groups in the short term. However, the results also suggest that the duration of the operational effects of pre-commercial thinning varies among insect groups; thus, the variable effects of pre-commercial thinning should be carefully considered in the conservation-based management of plantation stands. 相似文献
3.
Isono Chiaki Maruta Hitomi Ma Yun Ganeko Natsuki Miyake Tsuyoshi Yamashita Hiromi 《Fisheries Science》2020,86(6):1087-1099
Fisheries Science - The proximate composition and nutritional content of oysters define their quality and commercial value. Cultivation site and harvest date may impact these characteristics. We... 相似文献
4.
Ishinazaka T Suzuki M Yamamoto Y Isono T Harada N Mason JI Watabe M Tsunokawa M Ohtaishi N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(9):955-959
To study the luteal and placental function of pinnipeds, we analyzed the localization of steroidogenic enzymes (P450scc, 3 beta HSD and P450arom) in the corpus luteum and the placenta of ribbon seals (Phoca fasciata) and Steller sea lions (Eumetopias jubatus) immunohistochemically. P450scc and 3 beta HSD were present in all luteal cells of both species. Almost all of the luteal cells were immunostained for P450arom, while P450scc and 3 beta HSD were negatively immunostained in placentae and P450arom was present in the syncytiotrophoblast of placentae. These findings suggest that 1) corpora lutea of both species synthesize pregnenolone, progesterone and estrogen during the entire pregnancy period, and 2) like other terrestrial carnivores in the suborder Caniformia, placentae of both species do not have the capability for synthesizing progesterone in the latter half of active pregnancy period. 相似文献
5.
Ying-Hong He Sayaka Isono Yoko Kawaguchi-Ito Akito Taneda Ken-ichi Kondo Akihiko Iijima Kazuaki Tanaka Teruo Sano 《Journal of General Plant Pathology》2010,76(5):324-330
A 303-nucleotide viroid was isolated from an apple tree (Malus × domestica, ‘Fuji’) cultivated in Japan. The viroid had 84.9% overall nucleotide sequence homology to Apple dimple fruit viroid (ADFVd), a member of Pospiviroidae, reported from Italy. This viroid differed from the Italian variant by 47 mutations (38 substitutions, six deletions and three insertions), and most of these mutations occurred on either side of the central conserved region. The leaves and branches of the infected trees did not have any disease symptoms, but the fruits were dimpled and yellow. The infected scions were top-grafted onto a healthy ‘Fuji’ apple tree, which tested positive for this viroid in a northern hybridization analysis, and yellow dimple fruits were produced in the second growing season. We propose that this viroid is a new variant of ADFVd and causes yellow dimple fruit formation in ‘Fuji’ apple trees. 相似文献
6.
Makoto Kondo Randi Mulianda Masaya Matamura Toshiyuki Shibata Takashi Mishima Anuraga Jayanegara Naoto Isono 《Animal Science Journal》2021,92(1):e13530
Soluble sugars in feeds are important for ruminant production; however, performing numerous sugar analyses within a short period is a laborious task. Here, we developed a phenol-sulfuric acid (PSA) assay in a microplate format to quantify soluble sugars in ruminant feeds. This method is easy and quick and requires only a small quantity of harmful reagents. We found that assay measurements were not affected by the representative organic acids and sugar alcohol contained in feeds. The treatment of activated charcoal with ethanol extract prior to the PSA assay was effective in removing interfering compounds for a more accurate determination of soluble sugars in certain feeds. Furthermore, the inter-day and intra-day repeatability of the present method was acceptable. Hence, we conclude that the method developed in this study is suitable for routine analysis of soluble sugars content in ruminant feeds. 相似文献
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Hiroshi Hoshino Takeomi Isono Takuma Takayama Tsuyoshi Ishinazaka Akihiko Wada Yasunori Sakurai 《Fisheries Science》2006,72(5):922-931
Aerial and land-based sighting surveys were conducted to clarify the distribution of Steller sea lions during winter in the
northern Sea of Japan, along the west coast of Hokkaido, from 2001 to 2003. Aerial surveys revealed that sea lions gathered
around the Rishiri-Rebun Islands in March 2002 and 2003, and between Iwanai and Cape Obana in February 2003. Higher numbers
of sea lions were also confirmed at Cape Ofuyu and Cape Kamui on the central-west coast compared to that at the haul-out sites
in the 1980s on the upper-west coast in March 2002 and 2003. Additionally, fisherman observed sea lions along the coast of
the Tsugaru Strait from February to May 2003, where the presence of sea lions was not reported in the 1980s. These facts suggest
that sea lions have recently expanded their distribution southward. Land-based surveys at the recent haul-out sites indicated
that sea lions in the central-west coast were composed mainly of adult and subadult males (average: Cape Ofuyu 75.2%, Cape
Kamui 69.5%), which stayed from November 2002 to May 2003. In this area, sea lions arrived earlier and stayed longer than
in the 1980s. 相似文献
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