Cultural Neuroeconomics of Intertemporal Choice

According to theories of cultural neuroscience, Westerners and Easterners may have distinct styles of cognition (e.g., different allocation of attention). Previous research has shown that Westerners and Easterners tend to utilize analytical and holistic cognitive styles, respectively. On the other hand, little is known regarding the cultural differences in neuroeconomic behavior. For instance, economic decisions may be affected by cultural differences in neurocomputational processing underlying attention; however, this area of neuroeconomics has been largely understudied. In the present paper, we attempt to bridge this gap by considering the links between the theory of cultural neuroscience and neuroeconomic theory\ud of the role of attention in intertemporal choice. We predict that (i) Westerners are more impulsive and inconsistent in intertemporal choice in comparison to Easterners, and (ii) Westerners more steeply discount delayed monetary losses than Easterners. We examine these predictions by utilizing a novel temporal discounting model based on Tsallis' statistics (i.e. a q-exponential model). Our preliminary analysis of temporal discounting of gains and losses by Americans and Japanese confirmed the predictions from the cultural neuroeconomic theory. Future study directions, employing computational modeling via neural networks, are briefly outlined and discussed

Properties of star formation of the Large Magellanic Cloud as probed by young stellar objects

We perform a systematic study of evolutionary stages and stellar masses of young stellar objects (YSOs) in the Large Magellanic Cloud (LMC) to investigate properties of star formation of the galaxy. There are 4825 sources in our YSO sample, which are constructed by combining the previous studies identifying YSOs in the LMC. Spectral energy distributions of the YSOs from optical to infrared wavelengths were fitted with a model consisting of stellar, polycyclic aromatic hydrocarbon and dust emissions. We utilize the stellar-to-dust luminosity ratios thus derived to study the evolutionary stages of the sources; younger YSOs are expected to show lower stellar-to-dust luminosity ratios. We find that most of the YSOs are associated with the interstellar gas across the galaxy, which are younger with more gases, suggesting that more recent star formation is associated with larger amounts of the interstellar medium (ISM). N157 shows a hint of higher stellar-to-dust luminosity ratios between active star-forming regions in the LMC, suggesting that recent star formation in N157 is possibly in later evolutionary stages. We also find that the stellar mass function tends to be bottom-heavy in supergiant shells (SGSs), indicating that gas compression by SGSs may be ineffective in compressing the ISM enough to trigger massive star formation. There is no significant difference in the stellar mass function between YSOs likely associated with the interface between colliding SGSs and those with a single SGS, suggesting that gas compression by collisions between SGSs may also be ineffective for massive star formation.Comment: 26 pages, 16 figures, accepted for publication in Ap

Effectiveness of an oral care tablet containing kiwifruit powder in reducing oral bacteria in tongue coating : A crossover trial

Objectives: The aim of this study was to investigate the effect of an oral care tablet containing kiwifruit powder on oral bacteria in tongue coating compared with tongue brushing. Material and methods: Thirty‐two healthy, young adults were enrolled, and a crossover clinical trial was conducted. The volatile sulfur compound (VSC) concentration, Winkel tongue‐coating index (WTCI), and the number of total bacteria in addition to Fusobacterium nucleatum in tongue coating were measured. We instructed subjects to remove tongue coating by tongue brush for Intervention I, to keep the oral care tablet containing kiwifruit powder on the tongue dorsum and to let it dissolve naturally for Intervention II, and three oral care tablets 1 day before the measurement for Intervention III. Results: There were significant differences in terms of the level of H2S, VSC, and WTCI at Intervention I and all evaluation values at Intervention II. There were significant differences in terms of the level of H2S, VSC, WTCI, the number of total bacteria, and F. nucleatum at Intervention III. The value of WTCI, the number of bacteria, and F. nucleatum decreased significantly after taking the oral care tablets than after tongue brushing. When compared with Interventions I and III, Intervention III showed the effective results; there were significant differences in the number of total bacteria and F. nucleatum between tongue brushing and taking tablets. Conclusions: These results suggested that the oral care tablet containing kiwifruit powder could be effective in reducing total bacteria and F. nucleatum in tongue coating when compared with tongue brushing

Oral care tablet containing kiwifruit powder affects tongue coating microbiome

Objectives: Tongue coating, a kind of biofilm formed on the tongue dorsum, is the cause of various clinical conditions, such as oral halitosis and periodontal diseases, because Fusobacterium nucleatum acts as a bridge between other oral bacteria and periodontopathogenic bacteria in biofilm formation. Our previous clinical study revealed that taking oral care tablets containing kiwifruit powder significantly reduced not only tongue‐coating index and volatile sulfur compounds but also total bacteria and F. nucleatum in tongue coating. In this study, we analyzed the microbiome of tongue coating samples obtained before and after oral care tablets intake to clarify whether this tablet is a useful tool for daily tongue care. Methods: Thirty‐two healthy young adults were enrolled, and a crossover clinical trial was conducted. We instructed subjects to remove tongue coating by tongue brush for intervention I, to keep the oral care tablet containing kiwifruit powder on the tongue dorsum and to let it dissolve naturally for intervention II. Microbial DNA was isolated from the collected tongue coating samples in each subject, then 16S rRNA next‐generation sequencing, operational taxonomic unit clustering, and statistical analysis were performed. Results: The microbiome analysis revealed that the oral care tablet in intervention II prompted a significant change in the tongue microbiota composition, a significant reduction in the relative abundance of Prevotella and Porphyromonas, and an increase in Firmicutes/Bacteroidetes ratio when compared to that in intervention I. Conclusion: These results suggested that the oral care tablet might contribute to the improvement of the oral condition due to its good influence on the tongue coating microbiome

Frequency-dependent ERK phosphorylation in spinal neurons by electric stimulation of the sciatic nerve and the role in electrophysiological activity

The phosphorylation of extracellular signal-regulated kinase (pERK) in DRG and dorsal horn neurons is induced by the C-fiber electrical stimulation to the peripheral nerve. The present study was designed to investigate the expression and modulation of pERK in the rat dorsal horn neurons produced by repetitive electrical stimulation, and its involvement in the electrophysiological activity of dorsal horn neurons. Electrical stimulation of C-fiber intensity at different frequencies was applied to the sciatic nerve; the stimuli-induced pERK expression and the activity in dorsal horn neurons were studied by immunohistochemistry and extracellular recording, respectively. Electrical stimulation of C-fibers (3 mA) induced pERK expression in dorsal horn neurons in a frequency-dependent manner, indicating that the frequency of electrical stimulation is an important factor which activates the intracellular signal pathway in the spinal cord. To demonstrate the underlying mechanism of this frequency-dependent pERK expression, an NMDA receptor antagonist, MK-801, and a voltage sensitive calcium channel antagonist, nifedipine, were administrated intrathecally before the stimulation. We found that high frequency (0.5 Hz and 10 Hz) but not low frequent (0.05 Hz) stimulus-evoked pERK was partially inhibited by MK-801. Both high and low frequency stimulus-evoked pERK were inhibited by the nifedipine treatment. The extracellular single unit activities were recorded from the laminae I-II and V of the L4-5 dorsal horn, and we found that blockage of the intracellular ERK signal suppressed the wind-up responses in a dose-dependent manner. In contrast, any change in the mechanically evoked responses was not observed following the administration of ERK inhibitor. These observations indicate that ERK activation plays an important role in the induction of the wind-up responses in dorsal horn nociceptive neurons

The K2-ESPRINT Project III: A Close-in Super-Earth around a Metal-rich Mid-M Dwarf

We validate a $R_p=2.32\pm 0.24R_\oplus$ planet on a close-in orbit ($P=2.260455\pm 0.000041$ days) around K2-28 (EPIC 206318379), a metal-rich M4-type dwarf in the Campaign 3 field of the K2 mission. Our follow-up observations included multi-band transit observations from the optical to the near infrared, low-resolution spectroscopy, and high-resolution adaptive-optics (AO) imaging. We perform a global fit to all the observed transits using a Gaussian process-based method and show that the transit depths in all passbands adopted for the ground-based transit follow-ups ($r'_2, z_\mathrm{s,2}, J, H, K_\mathrm{s}$) are within $\sim 2\sigma$ of the K2 value. Based on a model of the background stellar population and the absence of nearby sources in our AO imaging, we estimate the probability that a background eclipsing binary could cause a false positive to be $< 2\times 10^{-5}$. We also show that K2-28 cannot have a physically associated companion of stellar type later than M4, based on the measurement of almost identical transit depths in multiple passbands. There is a low probability for a M4 dwarf companion ($\approx 0.072_{-0.04}^{+0.02}$), but even if this were the case, the size of K2-28b falls within the planetary regime. K2-28b has the same radius (within $1\sigma$) and experiences a similar irradiation from its host star as the well-studied GJ~1214b. Given the relative brightness of K2-28 in the near infrared ($m_\mathrm{Kep}=14.85$ mag and $m_H=11.03$ mag) and relatively deep transit ($0.6-0.7\%$), a comparison between the atmospheric properties of these two planets with future observations would be especially interesting.Comment: 11 pages, 9 figures, accepted to Ap

Evidence for Spin–Orbit Alignment in the TRAPPIST-1 System

In an effort to measure the Rossiter–McLaughlin effect for the TRAPPIST-1 system, we performed high-resolution spectroscopy during transits of planets e, f, and b. The spectra were obtained with the InfraRed Doppler spectrograph on the Subaru 8.2 m telescope, and were supplemented with simultaneous photometry obtained with a 1 m telescope of the Las Cumbres Observatory Global Telescope. By analyzing the anomalous radial velocities, we found the projected stellar obliquity to be λ = 1 ± 28° under the assumption that the three planets have coplanar orbits, although we caution that the radial-velocity data show correlated noise of unknown origin. We also sought evidence for the expected deformations of the stellar absorption lines, and thereby detected the "Doppler shadow" of planet b with a false-alarm probability of 1.7%. The joint analysis of the observed residual cross-correlation map including the three transits gave λ = 19_(-15)^(+13)°. These results indicate that the the TRAPPIST-1 star is not strongly misaligned with the common orbital plane of the planets, although further observations are encouraged to verify this conclusion

The middle region of an HP1-binding protein, HP1-BP74, associates with linker DNA at the entry/exit site of nucleosomal DNA

Kayoko Hayashihara, Susumu Uchiyama, Shigeru Shimamoto, Shouhei Kobayashi, Miroslav Tomschik, Hidekazu Wakamatsu, Daisuke No, Hiroki Sugahara, Naoto Hori, Masanori Noda, Tadayasu Ohkubo, Jordanka Zlatanova, Sachihiro Matsunaga, Kiichi Fukui. The Middle Region of an HP1-binding Protein, HP1-BP74, Associates with Linker DNA at the Entry/Exit Site of Nucleosomal DNA. Journal of Biological Chemistry, Volume 285, Issue 9, 2010, Pages 6498-6507. https://doi.org/10.1074/jbc.M109.092833