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[en] A centrosymmetric polymer precursor, 4-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)butan-1-amine (TPBA), was synthesized via a Knorr–Paal reaction and its copolymer with EDOT was electrochemically synthesized and characterized. While P(TPBA) has only two colors in its oxidized and neutral states, its copolymer with EDOT has eight different colors. Electrochromic devices based on P(TPBA)/PEDOT and P(TPBA-co-EDOT)/PEDOT were constructed and characterized. The oxidized state of the device shows blue color whereas it shows purple for the reduced state. At moderate potentials the device has good transparency with green and gray colors. The maximum contrast and switching time of the multielectrochromic copolymer device were measured as 25% and 0.8 s at 575 nm. Copolymerization not only increases the polymer’s color scheme, but also improves its properties, such as redox stability and switching time. (paper)
[en] The article reviews methods for the computer analysis and detection of so-called ionospheric earthquake precursors. It is shown that the applied techniques lead to quantitatively incomparable results due to the differences in determination of a reference undisturbed variation and in quantitative criteria of considering disturbances anomalous. As the existing techniques do not take into account the known sample standard deviation (provided by NASA along with the global ionospheric maps of total electron content for the Earth’s ionosphere), the amplitude of revealed anomalies cannot be compared to the level of natural variability of the ionosphere. To eliminate this shortcoming, we propose a few metrics to determine numerical criteria that enable to classify as anomalous the total electron content disturbances observed before strong earthquakes.
[en] Short-term earthquake (EQ) prediction is defined as prospective prediction with the time scale of about one week, which is considered to be one of the most important and urgent topics for the human beings. If this short-term prediction is realized, casualty will be drastically reduced. Unlike the conventional seismic measurement, we proposed the use of electromagnetic phenomena as precursors to EQs in the prediction, and an extensive amount of progress has been achieved in the field of seismo-electromagnetics during the last two decades. This paper deals with the review on this short-term EQ prediction, including the impossibility myth of EQs prediction by seismometers, the reason why we are interested in electromagnetics, the history of seismo-electromagnetics, the ionospheric perturbation as the most promising candidate of EQ prediction, then the future of EQ predictology from two standpoints of a practical science and a pure science, and finally a brief summary
[en] High-current fast electrons at the mega-ampere level provide a unique way to generate high-energy density states of matter, which are related to many applications. However, the large divergence angle of fast electrons typically over 50 degrees is a significant disadvantage. The guiding effect of the self-generated azimuthal magnetic fields on fast electron current is found to be very limited due to the cone-shaped spatial structure of the fields. In this work, we present a new understanding of the collimation conditions of fast electrons under such a magnetic field structure. It is shown that the transverse peak position of the magnetic field layer plays a more crucial role in collimating the fast electrons than its magnitude. Based upon this, a new two-pulse collimating scheme is proposed, where a guiding precursor pulse is adopted to form proper azimuthal magnetic fields and the main pulse is for fast electron generation as usual. The present scheme can be implemented relatively easily with the precursor lasers at the 10 TW level with a duration of 200 femtoseconds, with which the divergence angle of fast electrons driven by the main pulse can be confined within a few degrees. Practical applications of our scheme can be found in high-energy density science. (paper)
[en] Radon concentrations were measured in water of 4 wells on the Akşehir-Simav Fault System (ASFS) in Afyonkarahisar province from August 2009 to September 2010 and the relationship between radon anomalies and earthquake magnitudes was examined. Anomalous decreases in radon concentrations in the wells were observed to precede the earthquakes of magnitudes ranging from 2.6 M to 3.9 M. The correlation coefficients (R2) were 0.79, 0.93, 0.98 and 0.90 for the wells from 1 to 4, respectively, indicating that radon minima and earthquake magnitude were well correlated and suggesting that the groundwater radon, when observed at suitable sites, can be a sensitive tracer for strain changes in crust associated with earthquake occurrences. The relationship between the two parameters can be further improved as additional radon anomalies precursor to possible large earthquakes are recorded in the wells located on the ASFS in the future. This study strongly suggests that the continuous observations of radon concentrations in well water, especially at well 3, should be carried forward. - Highlights: ► Radon concentrations of 4 wells on the ASFS are reported for one-year period. ► Anomalous decreases were observed in radon concentrations in the wells. ► Radon minima are well correlated to the earthquake magnitude for each well. ► Groundwater radon minima may provide a forecasting for local disastrous earthquakes. ► The study suggests carrying on the continuous observations in this province.
[en] Neuromedin B (NMB), a mammalian bombesin-like peptide, regulates diverse physiological processes, such as energy metabolism, memory and fear behavior, and cellular growth, through its cognate receptor, NMBR. In this study, we report that NMB expression was upregulated during osteoclast development and that silencing NMB or NMBR attenuated osteoclast generation mediated by macrophage colony-stimulating factor (M-CSF) and receptor activator of NF-κB ligand (RANKL). We found that knockdown of NMB or NMBR using a small hairpin RNA suppressed M-CSF-induced proliferation of osteoclast precursor cells without altering osteoclast differentiation. Interestingly, NMB or NMBR knockdown reduced the expression of the M-CSF receptor, c-Fms, which is an important modulator of osteoclast development. Consequently, NMB or NMBR silencing inhibited M-CSF/c-Fms-mediated downstream signaling pathways like activation of ERK and Akt and induction of D-type cyclins, cyclin D1 and D2. Moreover, knockdown of NMB or NMBR accelerated apoptosis in osteoclast lineage cells by inducing caspase-3, caspase-9, and Bim expression. In summary, our study demonstrates that the NMB/NMBR axis plays a pivotal role in osteoclast generation by modulating the proliferation and survival of osteoclast lineage cells. - Highlights: • NMB and NMBR expression is regulated during osteoclast development. • NMB/NMBR axis regulates osteoclast generation mediated by M-CSF and RANKL. • NMB/NMBR silencing suppresses M-CSF-induced osteoclast precursor proliferation. • NMB/NMBR silencing accelerates apoptosis in osteoclast lineage cells.
[en] MicroRNAs (miRNAs) are short 18–23 nucleotide long noncoding RNAs that posttranscriptionally regulate gene expression by binding to mRNA. Our previous miRNA profiling of diffuse large B-cell lymphoma (DLBCL) revealed a mutation in the seed sequence of miR-142-3p. Further analysis now showed that miR-142 was mutated in 11 (19.64%) of the 56 DLBCL cases. Of these, one case had a mutation in both alleles, with the remainder being heterozygous. Four mutations were found in the mature miR-142-5p, four in the mature miR-142-3p, and three mutations affected the miR-142 precursor. Two mutations in the seed sequence redirected miR-142-3p to the mRNA of the transcriptional repressor ZEB2 and one of them also targeted the ZEB1 mRNA. However, the other mutations in the mature miR-142-3p did not influence either the ZEB1 or ZEB2 3′ untranslated region (3′ UTR). On the other hand, the mutations affecting the seed sequence of miR-142-3p resulted in a loss of responsiveness in the 3′ UTR of the known miR-142-3p targets RAC1 and ADCY9. In contrast to the mouse p300 gene, the human p300 gene was not found to be a target for miR-142-5p. In one case with a mutation of the precursor, we observed aberrant processing of the miR-142-5p. Our data suggest that the mutations in miR-142 probably lead to a loss rather than a gain of function. This is the first report describing mutations of a miRNA gene in a large percentage of a distinct lymphoma subtype
[en] The 0.15(Pb(Ni1/3Nb2/3)O3)-0.85(PbTiO3-PbZrO3) + xPbO (x = 0 ,3 ,6, 9 wt%, PNN-PZT) ceramics are investigated in order to obtain the lower sintering temperature and improve their piezoelectric properties using both conventional and two-step calcination method. The stoichiometric 0.15PNN-0.85PZT ceramics require the sintering temperature above 1000 .deg. C, but the addition of excess PbO in the 0.15PNN-0.85PZT ceramics display the sintering temperature of 900 .deg. C. The pyrochlore phases appear with increasing PbO concentrations in the conventional method, but it is exhibited the pure perovskite phases without appearing pyrochlore phases in the two-step calcinated samples. The 0.15PNN-0.85PZT ceramics with excess PbO are prepared by the two-step calcination process can be obtained with sintering temperature of 100 ∼ 200 .deg. C lower than those for the stoichiometric ceramics fabricated by conventional calcination method. The excess of PbO and two-step calcination method enhance not only the structural stability of the perovskite phase, but also the piezoelectric properties
[en] Using chemical-vapor deposition (CVD) precursors, group-IV compounds such as Si4C and Ge4C, which incorporate 20 at. percent carbon, have been synthesized. Here we present systematic ab initio studies of the electronic and structural properties of group-IV compounds formed from CVD precursors. We also propose a class of precursor molecules for materials containing 25 at. percent carbon. These compounds are energetically comparable to already synthesized materials (e.g., Ge4C) and are semimetallic within the local-density approximation. In addition, we give information for two previously proposed group-IV compounds, Si2Sn2C and Ge3SnC, which are direct-gap semiconductors and match the lattice of silicon to within 1 percent