941 research outputs found
Where does male-to-male aggression compromise cooperation?
We discuss how the diverse nature of aggression and cooperation can be understood if we focus our attention on where aggression reaches a compromise with non-aggression and/or cooperation in response to the relatedness between interactors. First we address whether Hamiltons rule explains the variation in male-to-male aggressiveness. Next we show that the variation in aggression and cooperation known in males of social spider mites (Saito, Evolution 49:413–417, 1995) can be explained by the change in relatedness (i.e. inclusive fitness) and effect of cooperative defence (synergistic effect). Then we learn that there is a sufficient condition of cooperation, which is determined primarily by two factors: the relatedness and synergistic effect of males. Furthermore, we expect that there is a condition where the aggression between males varies, depending upon how close the values of relatedness are to those of the sufficient condition of cooperation
Nest size variation reflecting anti-predator strategies in social spider mites of Stigmaeopsis (Acari: Tetranychidae)
The social spider mites (Acari: Tetranychidae) of Stigmaeopsis weave dense nests on the underside of host leaves. Four species occur on the leaves of bamboo in Japan: Stigmaeopsis longus, S. celarius, S. takahashii and S. saharai. We initially reconfirmed the occurrence of distinct variation in nest size among the species. Based on the hypothesis that this variation plays a role in protecting the spider mites from predators, we looked at the behavior of the natural enemies that occur on the host plants along with members of Stigmaeopsis. We found considerable variation in the ability of nests to protect the spider mite eggs. The smallest nests protected the eggs against 3 predators, whereas the largest nests protected the eggs only against one predator species. In other words, decreases in nest size increased egg defense. Thus we concluded that nest size variation reflects a strategy for reducing predation
Clinical Application of Sialic Acid I. On Serum Sialic Acid Contents in Patients
1) The contents of sialic acid in patients of various diseases sera were determined and increases of it were noticed in several diseases. 2) Sialic acid contents ranged between 50 and 100 mg./dl. in the normal serum.
3) But in the pathological serum, it ranged between 90 and 170 mg./dl. in cancer patients, between 80 and 110 mg./dl. in peptic ulcer, between 75 and 135 mg./dl. in arachnoiditis, and between 90 and 120 mg./dl. in epilepsy.
4) In other several diseases, sialic acid contents were determined.</p
21世紀日本における利益団体の存立・行動様式 : 全国社会団体調査(JIGS2調査)の分析 (特集 世界の市民社会・利益団体)
ニ〇〇七年段階(JIGS2調査)での日本の利益団体は、一九九七年(JIGS1)調査から一〇年を経て、いかに変貌を遂げたのか。この一〇年間の分析と研究経験をもとに、利益団体の記述枠組み(団体分類、活動空間レベル、ミクロ・メゾ・マク口、社会過程と政治過程)を構成し、それに基づいて初めての全国社会団体調査結果を記述し、比較し、分析する。日本における利益団体世界の鳥轍図を提示し、今後の研究の焦点と検証の方向性を示すとともに、利益団体世界の旧構造の粘着性と新しい変化の兆候を析出する
Tumor necrosis factor α (TNFα) induces pro-matrix metalloproteinase 9 production in human uterine cervical fibroblasts but interleukin 1 α antagonizes the inductive effect of TNFα
AbstractWe have examined the regulation of precursor of matrix metalloproteinase 9 (proMMP-9)/progelatinase B production by tumor necrosis factor α (TNFα) and interleukin 1α (IL-1α) using human uterine cervical fibroblasts. TNFα, but not IL-1α, induces the production of proMMP-9 in the cervical cells. IL-1α, however, suppresses the TNFα-induced proMMP-9 production. 12-O-tetradecanoylphorbol 13-acetate (TPA) also stimulates the cervical cells to produce proMMP-9, and IL-1α synergistically enhances its production. TNFα-induced proMMP-9 production is not mediated by protein kinase C (PKC), whereas the effect of IL-1α is through PKC. By contrast, proMMP-3/prostromelysin 1 is up-regulated by TNFα or TPA in the presence of IL-1α, whose modulation is PKC-dependent. The suppressive effect of IL-1α on the TNFα-induced proMMP-9 production is a new biological effect of IL-1 on MMP production
Enrichment and Characterization of an Ammonia-Oxidizing Archaeon of Moderate Thermophilic Taumarchaeotal Group I.1a from Cattle Manure Compost
Poster Presentatio
Level spectroscopy of the square-lattice three-state Potts model with a ferromagnetic next-nearest-neighbor coupling
We study the square-lattice three-state Potts model with the ferromagnetic
next-nearest-neighbor coupling at finite temperature. Using the
level-spectroscopy method, we numerically analyze the excitation spectrum of
the transfer matrices and precisely determine the global phase diagram. Then we
find that, contrary to a previous result based on the finite-size scaling, the
massless region continues up to the decoupling point with criticality in the antiferromagnetic region. We also check the universal
relations among excitation levels to provide the reliability of our result.Comment: 4 pages, 2 figure
Insect-induced daidzein, formononetin and their conjugates in soybean leaves.
In response to attack by bacterial pathogens, soybean (Gylcine max) leaves accumulate isoflavone aglucones, isoflavone glucosides, and glyceollins. In contrast to pathogens, the dynamics of related insect-inducible metabolites in soybean leaves remain poorly understood. In this study, we analyzed the biochemical responses of soybean leaves to Spodoptera litura (Lepidoptera: Noctuidae) herbivory and also S. litura gut contents, which contain oral secretion elicitors. Following S. litura herbivory, soybean leaves displayed an induced accumulation of the flavone and isoflavone aglycones 4',7-dihyroxyflavone, daidzein, and formononetin, and also the isoflavone glucoside daidzin. Interestingly, foliar application of S. litura oral secretions also elicited the accumulation of isoflavone aglycones (daidzein and formononetin), isoflavone 7-O-glucosides (daidzin, ononin), and isoflavone 7-O-(6'-O-malonyl-β-glucosides) (malonyldaidzin, malonylononin). Consistent with the up-regulation of the isoflavonoid biosynthetic pathway, folair phenylalanine levels also increased following oral secretion treatment. To establish that these metabolitic changes were the result of de novo biosynthesis, we demonstrated that labeled (13C9) phenylalanine was incorporated into the isoflavone aglucones. These results are consistent with the presence of soybean defense elicitors in S. litura oral secretions. We demonstrate that isoflavone aglycones and isoflavone conjugates are induced in soybean leaves, not only by pathogens as previously demonstrated, but also by foliar insect herbivory
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