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41.
Yuichi Preslie Kikuzawa Tai Chong Toh Chin Soon Lionel Ng Shu Qin Sam Daisuke Taira Lutfi Afiq‐Rosli Loke Ming Chou 《Aquaculture Research》2018,49(6):2249-2255
In coral mariculture, growth is one of the most common ways to track success. However, numerous methods of monitoring coral growth make comparative studies challenging. A literature review of 39 studies from 1982 to 2017 indicated that the most predominant non‐invasive methods used were linear and areal measurement and these were evaluated for their accuracy using nursery‐reared corals. The monthly change in linear and areal growth rates of six coral species (n = 215), Pocillopora acuta, Hydnophora rigida, Merulina ampliata, Podabacia crustacea, Echinopora lamellosa and Platygyra sinensis were measured via photogrammetry. We tested whether the planar area of coral colonies can be estimated using three geometric formulas of linear measurements. Based on the literature review, the six types of measurement methods were namely linear, volume, weight, area, count of polyps/branches and calcification, in decreasing order of application. Our results showed that the change in area calculated by geometric mean diameter (GMD) formulas provided the most accurate estimation among the three formulas and was strongly correlated with planar area (R2 ≥ .60; p < .05) for all coral species, except E. lamellosa and Pl. sinensis. However, our findings suggest that it is not ideal to use geometric formulas to estimate the change in area. Instead, we posit that areal photogrammetry represents the simplest yet accurate non‐invasive method for rapid monitoring of extensive areas of corals in situ. Lastly, we discuss the recommendations and limitations for areal photogrammetry. 相似文献
42.
通过野外现场调查,研究东苕溪中下游内河航运对鱼类多样性的影响。逐步回归分析结果显示,水体的浊度与船舶航运频率呈显著正相关;浊度与8种小型鱼类-彩鱊(Acheilognathus imberbis)、越南鱊(Acheilognathus tonkinensis)、方氏鳑鲏(Rhodeus fangi)、中华鳑鲏(Rhodeus sinensis)、高体鳑鲏(Rhodeus ocellatus)、餐(Hemiculter eucisculus)、食蚊鱼(Gambusia affinis)、子陵吻虾虎鱼(Rhinogobius giurinus)个体数呈显著负相关性(P<0.05);浊度与6种个体略大的鱼类-翘嘴鲌(Culter alburnus)、红鳍鲌(Chanodichthys thropterus)、油餐Hemiculter lucidus)、鲫(Carassius auratus)、麦穗鱼(Pseudorasbora parva)和间下鱵(Hyporhamphus intermedius)个体数负相关,但无显著性差异(P>0.05)。广义线性模型显示,物种丰度和Shannon Wiener多样性指数与水体浊度及人工护岸呈显著负相关;物种个体数与水体浊度、人工护岸结构及水深呈显著负相关(P<0.05)。浊度与鱼类体重关系的回归模型显示,浊度与平均体重和最小体重呈显著正相关(P<0.05),而浊度与最大体重无显著相关性(P>0.05)。研究表明,东苕溪中下游的内河航运可导致水体浊度增大,进而危害鱼类,其中对小型鱼类或幼鱼的危害更大。 相似文献
43.
Soichi Tanaka Keiichiro Shiraga Yuichi Ogawa Yoshihisa Fujii Shogo Okumura 《Journal of Wood Science》2014,60(3):194-200
To clarify the effect of pore conformation on the dielectric anisotropy of wood, the relative permittivity along the longitudinal and tangential axes of flat-sawn oven-dry specimens of 12 different wood species was measured using terahertz time-domain transmission spectroscopy and compared with the values calculated using the eigenvalue problem for two-dimensional photonic crystals. The measured dielectric anisotropy, which is the ratio of the relative permittivity along longitudinal axis to that along the tangential axis, was well explained by the calculated value. It was concluded that the ratio of tangential to radial widths of wood pores affects the relative permittivity along the tangential axis, and that the dielectric anisotropy decreased with an increase in the ratio. This discussion can also be applied to the relative permittivity in frequencies below 0.15 THz. These findings show promise as a new method for evaluating the porous structure of wood. 相似文献
44.
Akito Kaga Takehiko Shimizu Satoshi Watanabe Yasutaka Tsubokura Yuichi Katayose Kyuya Harada Duncan A. Vaughan Norihiko Tomooka 《Breeding Science》2012,61(5):566-592
Genetic variation and population structure among 1603 soybean accessions, consisted of 832 Japanese landraces, 109 old and 57 recent Japanese varieties, 341 landrace from 16 Asian countries and 264 wild soybean accessions, were characterized using 191 SNP markers. Although gene diversity of Japanese soybean germplasm was slight lower than that of exotic soybean germplasm, population differentiation and clustering analyses indicated clear genetic differentiation among Japanese cultivated soybeans, exotic cultivated soybeans and wild soybeans. Nine hundred ninety eight Japanese accessions were separated to a certain extent into groups corresponding to their agro-morphologic characteristics such as photosensitivity and seed characteristics rather than their geographical origin. Based on the assessment of the SNP markers and several agro-morphologic traits, accessions that retain gene diversity of the whole collection were selected to develop several soybean sets of different sizes using an heuristic approach; a minimum of 12 accessions can represent the observed gene diversity; a mini-core collection of 96 accession can represent a major proportion of both geographic origin and agro-morphologic trait variation. These selected sets of germplasm will provide an effective platform for enhancing soybean diversity studies and assist in finding novel traits for crop improvement. 相似文献
45.
Nakanishi Kosuke Usio Nisikawa Yokomizo Hiroyuki Takashima Tadao Hayashi Takehiko I. 《Paddy and Water Environment》2022,20(1):177-183
Paddy and Water Environment - Rice paddy fields are important habitat for many dragonfly species. In Japan, populations of dragonflies inhabiting rice paddies, in particular Sympetrum (Odonata:... 相似文献
46.
Effect of intramammary injection of rboGM-CSF on milk levels of chemiluminescence activity, somatic cell count, and Staphylococcus aureus count in Holstein cows with S. aureus subclinical mastitis 下载免费PDF全文
Hideyuki Takahashi Masaharu Odai Kenji Mitani Shigeki Inumaru Shozo Arai Rieko Horino Yuichi Yokomizo 《Canadian journal of veterinary research》2004,68(3):182-187
The effect of intramammary injection of recombinant bovine granulocyte-macrophage colony-stimulating factor (rboGM-CSF, 400 microg/10 mL) on quarter milk levels of chemiluminescence (CL) activity, and somatic cell count (SCC) and shedding pattern of Staphylococcus aureus was investigated. Ten Holstein cows, naturally infected with S. aureus were used, with either early-stage or late-stage subclinical mastitis. Injection of rboGM-CSF caused a remarkable increase in milk CL activity with a peak at 6 h after the cytokine injection in the early- and late-stage groups. In the early-stage group, milk SCC stayed around preinjection level at 6 h, rose significantly on days 1 and 2, and was followed by a smooth and significant decline to an under preinjection level (below 200 000 cells/mL) on day 7 postinjection. Alternatively, in the late-stage group, milk SCC rose significantly at 6 h after the cytokine injection and maintained high levels thereafter. The milk S. aureus count decreased drastically by the cytokine injection in the early-stage group. The bacterial count was moderately decreased in the late-stage group, but increased back to preinoculation levels on day 7 after the cytokine injection. The results suggest that the rboGM-CSF has a potential as a therapeutic agent for S. aureus infection causing subclinical mastitis of dairy cows, if the cytokine is applied at the initial stage of infection. 相似文献
47.
Sakiko Orui Sakaguchi Shigeru Shimamura Yuichi Shimizu Gen Ogawa Yuichiro Yamada Keiko Shimizu Hiroaki Kasai Hiroshi Kitazato Yoshihiro Fujiwara Katsunori Fujikura Kiyotaka Takishita 《Fisheries Science》2017,83(1):47-56
To identify the stomach contents of marine organisms, morphological observations are commonly conducted. However, the results obtained by this traditional method are frequently biased, as it is difficult to detect partially digested, soft-bodied organisms. To resolve this, recent studies have used DNA-based (DNA barcoding) analyses to examine the diet breadth of marine organisms. Here, we compared the prey richness of juvenile fishes using morphological observations and DNA-based analyses, with a focus on juvenile chum salmon Oncorhynchus keta. A higher number of prey taxa were successfully identified using DNA-based analyses than morphological observations. However, we also noticed several shortcomings of the DNA-based analyses, as reported in other diet-analysis studies that used molecular techniques. For example, the degree of digestion among prey taxa might have resulted in differential sensitivity to DNA detection. Additionally, several prey taxa could not be precisely identified, as the sequence data for some of the targeted organismal groups are unavailable in public gene databases. Remarkably, it is also possible that DNA-based analyses detected secondary prey, and therefore, the richness of prey taxa was likely overestimated. Thus, dietary analyses of juvenile fishes need to be carefully conducted, considering the respective advantages and disadvantages of DNA-based and morphological techniques. 相似文献
48.
Hirai T Oikawa M Inumaru S Yokomizo Y Kusakari N Mori K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(11):1249-1251
Effects of recombinant bovine granulocyte-macrophage colony-stimulating factor (rboGM-CSF) on bactericidal activity of bovine peripheral blood neutrophils in vitro and in vivo were studied. In in vitro experiment, bovine blood neutrophils were cultured for 9 hr in media containing 0.005, 0.05 or 0.5 microg/ml of rboGM-CSF. Neutrophils treated with rboGM-CSF showed significantly higher luminol-dependent chemiluminescence (LDCL) than control cells. In in vivo experiment, neutrophils isolated from cows injected 5.0 microg/kg of rboGM-CSF showed significantly higher Nitrobluetetrazolium (NBT) reduction value than that from control cows 24 hr post injection. Total leukocyte counts of cows injected rboGM-CSF sharply decreased 6 hr post injection and recovered to normal level 2 days post injection. Body temperature of these cows rose 6 hr post injection and back to normal level at 24 hr post injection. It was suggested that rboGM-CSF enhanced bactericidal activity of bovine neutrophils both in vitro and in vivo. 相似文献
49.
Terutaka Mori Yasumitsu Kato Tetsuya Takagi Yukio Onoda Yuichi Kayaba 《Ecology of Freshwater Fish》2018,27(4):1015-1022
Riverine systems are inherently dendritic in nature, and turbid water may not necessarily flow equally throughout an entire catchment. Tributaries have the potential to serve as refugia from temporarily turbid water in the main stem. As ayu (Plecoglossus altivelis) are one of the important species for the inland fisheries industry and recreational fishing, their behaviour in a branched river network is a primary concern. We released ayu with radio‐transmitting tags into two experimental streams that joined at a downstream pool. Turbid water was released into one of the streams, and we identified whether avoidance movement of ayu between the two experimental streams was triggered by flowing turbid water. The suspended solid concentration elevated rapidly after adding the turbid water and was maintained at more than 400 mg/L for 3 hr. Avoidance movement of ayu was triggered when the suspended solid concentration exceeded approximately 200 mg/L. Then, most ayu moved from the turbid stream to the nonturbid one, leading to a difference in ayu density between the two streams. Therefore, we demonstrated that turbid water induced interstream movement of a commercially important ayu as refuge behaviour, suggesting that river connectivity is important for the persistence of the ayu. 相似文献
50.