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1.
Akihisa Hattori 《Journal of Ethology》2006,24(1):51-57
The distribution patterns of the leathery sea anemone, Heteractis crispa, which contains an algal endosymbiont (zooxanthellae) and anemonefish, were investigated in relation to size distribution on a shallow fringing reef (3.2 ha, 0–4 m depth) in Okinawa, Japan. Individual growth and movements were also examined. Large individuals (>1,000 cm2) inhabited reef edges up to a depth of 4 m, while small anemone (<500 cm2) inhabited shallow reefs including inner reef flats. Individuals rarely moved, and their sizes were significantly correlated with their water depths. Growth of small anemones was negatively correlated with their distance from the reef edge, suggesting that reef edges provide more prey and lower levels of physiological stress. This study suggested that deep reef edges are suitable habitats for H. crispa. Large anemones were inhabited by large Amphiprion perideraion or large Amphiprion clarkii, both of which are effective defenders against anemone predators. Anemones that settle in deep reef edges may enjoy a higher survival rate and attain a large size because of their symbiotic relationship with anemonefish. However, early settlers do not harbor anemonefish. Their mortality rate would be higher in the deep edges than in shallow edges, the complicated topography of which provides refuge. 相似文献
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Jesús Olivero John E. Fa Miguel A. Farfán Jerome Lewis Barry Hewlett Thomas Breuer Giuseppe M. Carpaneto María Fernández Francesco Germi Shiho Hattori Josephine Head Mitsuo Ichikawa Koichi Kitanaishi Jessica Knights Naoki Matsuura Andrea Migliano Barbara Nese Andrew Noss Dieudonné Ongbwa Ekoumou Pascale Paulin Raimundo Real Mike Riddell Edward G. J. Stevenson Mikako Toda J. Mario Vargas Hirokazu Yasuoka Robert Nasi 《PloS one》2016,11(1)
Pygmy populations occupy a vast territory extending west-to-east along the central African belt from the Congo Basin to Lake Victoria. However, their numbers and actual distribution is not known precisely. Here, we undertake this task by using locational data and population sizes for an unprecedented number of known Pygmy camps and settlements (n = 654) in five of the nine countries where currently distributed. With these data we develop spatial distribution models based on the favourability function, which distinguish areas with favourable environmental conditions from those less suitable for Pygmy presence. Highly favourable areas were significantly explained by presence of tropical forests, and by lower human pressure variables. For documented Pygmy settlements, we use the relationship between observed population sizes and predicted favourability values to estimate the total Pygmy population throughout Central Africa. We estimate that around 920,000 Pygmies (over 60% in DRC) is possible within favourable forest areas in Central Africa. We argue that fragmentation of the existing Pygmy populations, alongside pressure from extractive industries and sometimes conflict with conservation areas, endanger their future. There is an urgent need to inform policies that can mitigate against future external threats to these indigenous peoples’ culture and lifestyles. 相似文献
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K Imada M Tsudo T Kodaka K Itoh N Arima T Hattori M Okuma T Uchiyama 《Biochemical and biophysical research communications》1992,188(1):352-357
The molecular mechanism of erythroid differentiation has been still ill-defined. In this study, we introduced a human interleukin-2 receptor (IL-2R) beta chain cDNA into ELM-I-1 cells which differentiated into hemoglobin-positive cells in the presence of erythropoietin (Epo), and established the transformant which expressed IL-2R beta chain. In this transformant, we revealed that IL-2 induced erythroid differentiation and the same pattern of tyrosine phosphorylation as Epo. These data suggest that tyrosine phosphorylation is involved in signal transduction pathway of erythroid differentiation. It is also implicated that the Epo and IL-2 receptor system share a common signal transduction pathway. 相似文献
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-Octopamine was characterized as substrate for monoamine oxidase (MAO) in rat brain and liver mitochondria. The m and max values of the brain enzyme were 735 μM and 32.5 nmoles/mg protein/30 min, and those of the liver enzyme 351 μM and 125 nmoles/mg protein/30 min, respectively. The inhibition experiments with clorgyline and deprenyl showed that -octopamine was a common substrate for type A and type B MAO, though a major part of the activity was due to type A enzyme. 相似文献
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Masahiro Matsunaga Tokiko Isowa Kaori Yamakawa Seisuke Fukuyama Jun Shinoda Jitsuhiro Yamada Hideki Ohira 《PloS one》2014,9(4)
Happiness has been viewed as a temporary emotional state (e.g., pleasure) and a relatively stable state of being happy (subjective happiness level). As previous studies demonstrated that individuals with high subjective happiness level rated their current affective states more positively when they experience positive events, these two aspects of happiness are interrelated. According to a recent neuroimaging study, the cytosine to thymine single-nucleotide polymorphism of the human cannabinoid receptor 1 gene is associated with sensitivity to positive emotional stimuli. Thus, we hypothesized that our genetic traits, such as the human cannabinoid receptor 1 genotypes, are closely related to the two aspects of happiness. In Experiment 1, 198 healthy volunteers were used to compare the subjective happiness level between cytosine allele carriers and thymine-thymine carriers of the human cannabinoid receptor 1 gene. In Experiment 2, we used positron emission tomography with 20 healthy participants to compare the brain responses to positive emotional stimuli of cytosine allele carriers to that of thymine-thymine carriers. Compared to thymine-thymine carriers, cytosine allele carriers have a higher subjective happiness level. Regression analysis indicated that the cytosine allele is significantly associated with subjective happiness level. The positive mood after watching a positive film was significantly higher for the cytosine allele carriers compared to the thymine-thymine carriers. Positive emotion-related brain region such as the medial prefrontal cortex was significantly activated when the cytosine allele carriers watched the positive film compared to the thymine-thymine carriers. Thus, the human cannabinoid receptor 1 genotypes are closely related to two aspects of happiness. Compared to thymine-thymine carriers, the cytosine allele carriers of the human cannabinoid receptor 1 gene, who are sensitive to positive emotional stimuli, exhibited greater magnitude positive emotions when they experienced positive events and had a higher subjective happiness level. 相似文献
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