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1.
The advent of social media expands our ability to transmit information and connect with others instantly, which enables us to behave as “social sensors.” Here, we studied concurrent bursty behavior of Twitter users during major sporting events to determine their function as social sensors. We show that the degree of concurrent bursts in tweets (posts) and retweets (re-posts) works as a strong indicator of winning or losing a game. More specifically, our simple tweet analysis of Japanese professional baseball games in 2013 revealed that social sensors can immediately react to positive and negative events through bursts of tweets, but that positive events are more likely to induce a subsequent burst of retweets. We confirm that these findings also hold true for tweets related to Major League Baseball games in 2015. Furthermore, we demonstrate active interactions among social sensors by constructing retweet networks during a baseball game. The resulting networks commonly exhibited user clusters depending on the baseball team, with a scale-free connectedness that is indicative of a substantial difference in user popularity as an information source. While previous studies have mainly focused on bursts of tweets as a simple indicator of a real-world event, the temporal correlation between tweets and retweets implies unique aspects of social sensors, offering new insights into human behavior in a highly connected world. 相似文献
2.
Shiraishi Tomonori; Araki Miwa; Yoshioka Hirofumi; Kobayashi Issei; Yamada Tetsuji; Ichinose Yuki; Kunoh Hitoshi; Oku Hachiro 《Plant & cell physiology》1991,32(7):1067-1075
A pathogenic fungus of pea, Mycosphaerella pinodes, secretesa so-called "suppressor" in its pycnospore germination fluid.The suppressor blocks the defense responses and induces localsusceptibility (accessibility) in pea plants to agents thatare not pathogenic in pea. The suppressor nonspecifically inhibitsthe ATPase activity in plasma membranes prepared from pea, soybean,kidney bean, cowpea and barley plants. However, cytochemicalstudies by electron microscopy indicate that the suppressorspecifically inhibits the ATPase in pea cell membranes, butnot in those of four other plant species tested. That is, thespecificity of the suppressor appears at the cell and/or tissuelevel, but is not evident in vitro. Furthermore, the inhibitoryeffect of the suppressor is temporary because the ATPase activityrecovers 9 h after the treatment. A similar effect was observedafter inoculation with M. pinodes but not with a nonpathogenof pea, M. ligulicola. The role of the suppressor in host-parasitespecificity is discussed. (Received April 9, 1991; Accepted August 6, 1991) 相似文献
3.
T Inoue N Watanabe S Saito M Yamasaki H Saito N Shirakawa 《Endocrinologia japonica》1986,33(6):919-927
A highly sensitive and specific RIA for IGF-I has been developed using recombinant DNA-derived IGF-I of very high purity and specific antiserum to it. This assay system could detect IGF-I at as low concentrations as 20-30 ng/ml. The intra-assay and interassay coefficients of variation at various concentrations of IGF-I were 4.9 to 6.5% and 5.4 to 8.0%, respectively. The recovery rate of pure IGF-I added to plasma was 77.0 +/- 3.7%. The antiserum did not cross-react with porcine insulin, biosynthetic human insulin, hGH, hEGF, the synthetic C-domain of IGF-I or that of IGF-II, but reacted equally with an analog, Thr59-IGF-I. Plasma IGF-I was extracted by the acid-ethanol method before assay to separate IGF-I from its binding protein. When plasma IGF-I was assayed without extraction, the inhibition curves of serial dilution of plasma samples from several individuals were not parallel to the standard curve of IGF-I. The plasma concentration of IGF-I was 147 +/- 49 ng/ml (mean +/- SD) in 156 normal adults aged from 20-59 years. As reported by others, the IGF-I levels were low in cord plasma (41.8 +/- 23.5 ng/ml) and plasma of patients with GH deficiency (64.6 +/- 42.0 ng/ml), while its levels were high in normal children of pubertal ages (12-13 yr, 365 +/- 126 ng/ml) and in patients with active acromegaly (562 +/- 115 ng/ml). This RIA system is a simple and useful method for determining plasma IGF-I in normal and diseased states. 相似文献
4.
5.
The glycoprotein nature of solubilized muscarinic acetylcholine receptors from bovine cerebral cortex 总被引:4,自引:0,他引:4
O Shirakawa T Kuno C Tanaka 《Biochemical and biophysical research communications》1983,115(3):814-819
Muscarinic acetylcholine receptors were solubilized from bovine cerebral cortex with 3-[(3-cholamidopropyl)-dimethylammonio]-1-propane sulfonate. The so-obtained receptors could be precipitated by Wheat Germ (73%), Concanavalin A (55%), Lens Culinaris (36%) and Ricinus Communis (26%), but not by Peanut, Dolichus Biflorus and Ulex Europaeus. On Wheat Germ- and Concanavalin A-affinity chromatography, the solubilized muscarinic receptors were retained on both columns and subsequently eluted with N-acetylglucosamine and alpha-methyl-D-mannoside, respectively. A high concentration (100 micrograms/ml) of Wheat Germ or Concanavalin A did not interfere with Z-[3H]quinuclidinyl benzilate binding, thereby suggesting that the lectin binding sites are not directly involved in the receptor binding function. These solubilized muscarinic receptors are postulated to contain carbohydrate residues, N-acetyl-glucosamine, mannose and galactose, as glycoprotein. 相似文献
6.
Nakao T Narita S Tanaka K Hara H Shirakawa J Noshiro H Saga N Tsunoda N Kawata K 《Theriogenology》1983,20(1):111-119
The effect of an intramuscular injection of a new analog of gonadotropin-releasing hormone (GnRH), fertirelin, on the first-service pregnancy rate in cows was investigated by a double blind experiment. A total of 1,194 cows was injected intramuscularly either with 100 mug of GnRH or placebo (physiological saline solution) at the time of first insemination postpartum. Pregnancy rate (number of cows calved/ number of cows serviced) was 57.2 % in 605 cows treated with GnRH, while the performance was 49.7 % in 589 cows of the placebo group. The difference of pregnancy rates in both groups was significant (P<0.05). GnRH injected at insemination was effective, especially in cows at the first and third lactations, cows at 101 days postpartum or later, cows with daily milk yield of 26-30 kg, and also in cows from the area where a regional average fertility was relatively low. 相似文献
7.
Tentative identification of a "maturation enzyme" for precursor 16 s ribosomal RNA in Escherichia coli 总被引:3,自引:0,他引:3
A Yuki 《Journal of molecular biology》1971,62(2):321-329
8.
The interactions of benzoquinones with the reduced forms ofthe bound plastoquinone acceptors, QA and QB, were studied withoxygen-evolving photosystem II (PS II) particles from the thermophiliccyanobacterium Synechococcus elongatus, which largely lack poolplastoquinone molecules [Takahashi and Katoh (1986) Biochim.Biophys. Acta 845: 183]. Oxygen evolution in the presence ofvarious electron acceptors was determined and flash-inducedchanges in absorbance in the blue region were analyzed in termsof difference spectra, dependence on the concentration of benzoquinoneand on temperature, and sensitivity to 3-(3,4-dichlorophenyl)-1,1-dimethylurea(DCMU). The more hydrophobic the quinone molecule, the higherwas the rate of oxygen evolution, and the maximum rate of 3,000µmoles O2.(mg chlorophyll)1.h1 was recordedin the presence of phenyl- and dichloro-p-benzoquinones. DCMUinhibited oxygen evolution by more than 95%. However, spectrophotometricstudies revealed that, even though electrons were transferredto benzoquinones predominantly via the direct oxidation of by added benzoquinones occurred in such a way as to indicate thatabout 40% of PS II reaction centers were not associated withfunctional QB sites. was very stable in the presence of ferricyanide. However, benzoquinonesinduced the slow oxidation of . The characteristics of the benzoquinone reductioin in thePS II preparation is discussed.
1Present address: Department of Life Sciences, Faculty of Science,Himeji Institute of Technology, Shosha 2167, Himejishi, Hyogo-ken,671-22 Japan (Received May 8, 1990; Accepted August 14, 1990) 相似文献
9.
Tomokazu Indoh Sachiko Shirakawa Tohru Kubota Teruo Yashiki Emiko Isogai Nobuhiro Fujii 《Microbiology and immunology》1996,40(9):675-679
Persistent infections with mumps virus were established in several human lymphoid cells of T-cell origin (Molt-4, TALL-1, and CCRF-CEM) and human monocyte cells (U937 and THP-1). 2′,5′-Oligoadenylate synthetase (2–5AS) activity was demonstrated to be only slightly induced by interferon (IFN) or TPA (12-O-tetradecanoyl-phorbol-13-acetate) treatment in these cells. Treatment of the persistently infected cells with IFN or TPA did not stimulate an increase in the amount of synthetase mRNA. Induction of cell differentiation and augmentation of IFN production by TPA were demonstrated in U937 cells persistently infected with mumps virus (U937-MP). Similar results for IFN production were obtained from differentiated U937 cells. It is suggested that cell differentiation of U937 cells might be associated with the development of IFN inducibility. 相似文献