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81.
The mechanism of mass collaboration in risk management was studied during the Sichuan earthquake under a Web-based “PeopleFinder” project, where information is contributed and shared among mass contributors. The case study is provided by a great earthquake that happened in Wenchuan County, Sichuan Province, of southwestern China at 2:28 p.m. on May 12, 2008. We witnessed and experienced the rescue and relief efforts for the great earthquake. In this article, two fundamental frameworks are developed to study the mechanism of mass collaboration. Mass collaboration is proven to be effective in a big public crisis such as the Sichuan earthquake. 相似文献
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Nacrein-like proteins have carbonic anhydrase (CA)-like domains, but their coding regions are flanked by inserted repeat sequence, such as Gly-X-Asn. Reportedly, nacrein-like proteins show the highest similarity to human carbonic anhydrase 1(α-CA1), possess CA catalytic functions, and play a key role in shell biomineralization. In the present study, two novel nacrein-like proteins were firstly identified from the shell-forming mantle of the Pacific oyster Crassostrea gigas. With numerous analyses, it was identified and characterized that both the nacrein-like proteins F1 and F2 were secreted and most closely related to the nacrein-like protein of California mussel Mytilus californianus via phylogenetic analysis. RT-PCR analysis showed that the nacrein-like proteins F1 and F2 were expressed in multiple tissues and the expression levels remarkably rose after entering the spat stage, which were basically consistent with the increase of calcite fractions in the total shell volume. Surprisingly, the Gly-X-Asn repeat domain, which is distinctive in most nacrein-like proteins, was absent in the two newly identified nacrein-like proteins in C. gigas and replaced with a series of acidic amino acids (D/E). Regardless, nacrein-like proteins in mollusks seem to be vital to the deposition of calcium carbonate and likely perform diverse functions. 相似文献
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M. I. Ibragimova A. I. Chushnikov G. V. Cherepnev V. Yu. Petukhov E. P. Zheglov 《Biophysics》2014,59(3):425-430
The iron metabolism was studied in serum blood samples collected from 26 professional sportsmen undergoing intensive physical exercises using EPR combined with hematological and biochemical laboratory tests. Only 23% of EPR spectra (n = 6) were practically normal while in the rest spectra additional abnormal absorption lines were detected. Presumably, the significant portion of new signals may be caused by different cytochromes. Moreover, the anisotropic signals with g 1 ? 2.02; g 2 ? 1.94 and g 3 ? 1.86 registered in some spectra pointed to the sulfur-iron centers. There was nearly linear correlation between the concentration of Fe3+ in transferrin (Fe3+-Tf) obtained from the EPR spectra and the serum iron concentration measured by absorption photometry both for sportsmen and controls (healthy individuals and patients with different diseases). At equal serum iron concentrations the Fe3+-Tf level was higher in sportsmen than that in controls. The Pearson correlation coefficient (r) for Fe3+-Tf and serum iron values was equal to 0.89 in sportsmen versus r = 0.97 in controls. Additional new lines in serum EPR spectra of professional sportsmen prove the suitability of EPR assay for scheduled medical exams since routine biochemical and hematological tests are insufficient to discover all abnormalities in iron metabolism under intensive physical exercises. 相似文献
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M. V. Slavutskaya A. V. Kirenskaya V. Yu. Novototskii-Vlasov V. V. Shul'govskii I. B. Kozlovskaya 《Human physiology》2005,31(5):545-553
The parameters of saccades and presaccadic slow potentials were studied in right-handed men with a dominant right eye, including 19 schizophrenics and 12 healthy subjects. For visual stimulation, three light-emitting diodes were used, which were located in the center of the visual field (the central fixation stimulus) and 10° to the right and left of it (peripheral stimuli). Two stimulation protocols were used: with a simultaneous switching off of the central fixation stimulus and switching on of the peripheral stimuli (test 1) and with an interstimulus gap of 200 ms (test 2). According to the latency, saccades were divided into anticipatory, express, and regular. Slow EEG potentials preceding regular saccades were analyzed. It was found that the proportion of anticipatory saccades is considerably higher than the normal value in schizophrenia. The analysis of the presaccadic potentials demonstrated a significant decrease in the amplitude of negative potentials in the vertex region at early stages of presaccadic preparation and its increase in the occipital region at late stages. Test 2 in the patients demonstrated an increase in the positivity focus in the frontal region of the right hemisphere. It was assumed that the alterations found in schizophrenia result from the deficit of frontal cortical fields. 相似文献
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Fertilized eggs of Sebastes schlegelii, Sebastes pachycephalus and Sebastes hubbsi are morphologically similar under stereomicroscope. However, under the scanning electron microscope, significant differences in the ultrastructures of the egg surface among the three species were observed, and herein, a taxonomic key was proposed for future applications. A clustering analysis based on the ultrastructures of the egg surface and the diameter of the oil globule suggested that among the three species, S. hubbsi and S. pachycephalus were more genetically similar, while S. schlegelii had diverged earlier. The results agree with the conclusions drawn from morphological and molecular analyses on adult samples of the same species. 相似文献