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1.
Noriyuki Koizumi Atsushi Mori Takuya Mineta Eiji Sawada Keiji Watabe Takeshi Takemura 《Paddy and Water Environment》2017,15(4):723-730
Fecal DNA samples from the red-eared slider and Reeves’ pond turtle, suspected pests of lotus root paddies, were used to identify the plant species eaten by these turtles in order to develop a strategy for rural ecosystem conservation. The fecal samples were obtained from young and adult individuals (mostly female) of both species living in agricultural canals surrounding lotus root paddies in Tokushima Prefecture, Japan. The samples were screened for the presence or absence of DNA from nine plant species using PCR and plant species-specific primers for the rbcL gene of chloroplast DNA. In the red-eared slider, our analysis identified seven plant species in the fecal DNA samples of adults and three plant species in those of young individuals. In Reeves’ pond turtle, our analysis identified two plant species from adult fecal samples and one species from those of young individuals. Thus, adult red-eared sliders consume a greater range of plants than young red-eared sliders or Reeves’ pond turtles. Both turtle species, independently of age, consumed lotus plants and were likely to cause feeding damage to lotus roots. Considering the plant species detected in adult red-eared sliders and these plant habitats, we suggest that this adult turtle is likely to travel between the agricultural canals and the lotus root paddies. These findings will help the development of strategies for preventing damage to lotus roots by these turtles; furthermore, they indicate that fecal DNA analysis will be applicable to investigation of the feeding habits of other animal species. 相似文献
2.
Nakagawa Koki Murase Jun Asakawa Susumu Watanabe Takeshi 《Journal of Soils and Sediments》2020,20(11):4034-4041
Journal of Soils and Sediments - To reveal whether microaerophilic Fe(II)-oxidizing bacteria (FeOB) participate in the Fe(II) oxidation at the oxic-anoxic interface in flooded paddy field soil,... 相似文献
3.
Saitoh Kanae Yoshimura Tomohiro Sun Luchuanyang Yang Min Wang Yao Taniyama Shigeto Hara Kenji Murayama Fumihito Nikawa Takeshi Tachibana Katsuyasu Hirasaka Katsuya 《Fisheries Science》2020,86(1):187-196
Fisheries Science - Fish oil containing omega-3 polyunsaturated fatty acids (PUFA) attenuates chronic inflammation found in obesity, leading to a reduction in insulin resistance. The effect of fish... 相似文献
4.
Fisheries Science - The present study established an age determination technique and analyzed growth patterns in three sculpins, Myoxocephalus jaok, Enophrys diceraus, and Gymnocanthus... 相似文献
5.
Bhuminad DEVKOTA Masahiro TAKAHASHI Saori SATO Kouya SASAKI Atsushi UEKI Takeshi OSAWA Masahiro TAKAHASHI Norio YAMAGISHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(7):875-878
Blood samples were obtained sequentially from 10 dairy cows around the time of
parturition to assess plasma fluctuations in estradiol-17β (E2) levels in
association with those of several bone resorption markers. Plasma E2
concentration increased sharply a few days prepartum and decreased quickly after
parturition. In terms of bone resorption markers, the plasma level of tartrate-resistant
acid phosphatase isoform 5b (TRAP5b) rose significantly, commencing 1 week prepartum, and
was maintained at this level to a few days postpartum. The plasma concentration of
carboxyterminal collagen cross-links of type-I collagen (CTx) increased significantly
after parturition. These observations suggest that osteoclast-mediated bone resorption was
activated after parturition when plasma E2 concentrations decreased. 相似文献
6.
Masato HIYAMA Ken Takeshi KUSAKABE Ai TAKESHITA Sinji SUGI Nobue KUNIYOSHI Hiroyuki IMAI Kiyoshi KANO Yasuo KISO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(3):305-311
LC3 − the mammalian homolog of Atg8 − was found as autophagosome membrane binding protein
in mammals and widely used as an autophagosomal marker. LC3A, B and C show different
expression patterns in each tissue. The aim of this study was to reveal the differences of
expression patterns among LC3 families in mouse placenta under normal condition and
nutrient starving condition. LC3A and B were highly expressed in decidual cells. LC3A and
B were increased in D14 compared with D12 and D16 in mouse placenta, while LC3C was
decreased. Starvation induced increase in LC3B expression specifically.
Immunohistochemistry showed different expression patterns among LC3A, B and C. LC3A
expression in syncytiotrophoblast was vanished by starvation. The results of real time
RT-PCR suggested differences between D12 and D16 in autophagic cascade induced by
starvation. Taken together, this study suggests that autophagy could play a role in
placental invasion system and that nutrient starvation affects LC3B expression. 相似文献
7.
Takeshi OHTA Shuichi KIMURA Masaya HIRATA Takahisa YAMADA Toshie SUGIYAMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1327-1330
The Spontaneously Diabetic Torii (SDT) fatty rat, a model for obese type 2 diabetes,
shows bone quantitative abnormalities, namely low bone mineral density (BMD). The
objective of this study was to evaluate bone morphological changes, in particular
identifying the bone qualitative abnormalities, in the SDT fatty rat. Male SDT fatty rats
showed increases in total trabecular area and trabecular number and decreases in
trabecular thickness in cancellous bones of the proximal tibia, indicating trabecular
miniaturization. The SDT fatty rat is useful for investigation of pathophysiological
changes in bone quality in diabetic osteoporosis. 相似文献
8.
Two new amino acid-type amphoteric surfactants — disodiumN-(2-fatty acyl amino) ethyliminodiacetate and disodiumN-(2-fatty acyl amino) ethyl-N,N-bis[3-(2-hydroxy) propylsulfonate] amine — were synthesized using tall oil fatty acids as the raw material. Suitable processing conditions for synthesizing the intermediates and final products were probed. In addition, the chemical structures of the intermediates and the final products were identified by infrared spectroscopy, hydrogen nuclear magnetic resonance spectroscopy, and elemental analysis. 相似文献
9.
Takashi Masaki Shigeta Mori Takuya Kajimoto Gaku Hitsuma Satoshi Sawata Masuo Mori Katsuhiro Osumi Shobu Sakurai Takeshi Seki 《Journal of Forest Research》2006,11(4):217-225
The individual growth of tree diameter at breast height (dbh) is analyzed in an even-aged plantation of Cryptomeria japonica from stand age of 45 to 94 years, to examine how the growth of individual trees has been affected by the changes in spacing
resulting from thinning operations. At any age, a significant proportion (0.37–0.46) of the variation in dbh growth during
a 5–11-year period was explained by dbh at the beginning of the period, probably due to greater leaf mass of larger trees.
Next, either one-sided or two-sided competition was added to the model, by calculating the basal area (BA) of neighboring
trees around each tree within a given radius or BA for trees having larger dbh than the focal tree within the radius. After
preliminary analyses, a radius of 8 m was selected as the critical range for tree competition. Although both types of competition
explained a significant proportion (0.09–0.43) of growth variation, one-sided competition was not significant at ages greater
than 54 years. Based on the model at 45 years of age, the initial deviation of growth rate for each tree from the predicted
rate was calculated and added to the models as a third variable. This raised the coefficient of determination up to 0.50–0.74.
These findings have practical significance for forest plantation management, particularly for controlling the growth of standing
trees via thinning, to produce high-quality timber in the future. 相似文献
10.
Variations in the composition of low boiling point (LBP) monoterpenes emitted from needle samples of 150 hinoki (Chamaecyparis obtuse) trees (30 strains, each with five clones) native to Shimane Prefecture, Japan, were investigated using a headspace technique.
The assays revealed considerable proportional variations especially in the amount of sabinene, which ranged from 24% to 78%
of the total LBP monoterpenes. The proportions of α-pinene, myrcene, and limonene negatively correlated with that of sabinene overall. In particular, the proportion of limonene
showed clear negative correlation with that of sabinene (r = −0.98). Differences in the proportion of sabinene among five
clones in each strain were less than 15% in 22 out of 30 strains, indicating that monoterpene composition is constitutively
steady in most strains. In a few strains, however, considerable variation in the composition was observed among clones. 相似文献