383 research outputs found
Super-resolution imaging for the detection of low-energy ion tracks in fine-grained nuclear emulsions
We propose a new wide-field imaging method that exploits the Localized
Surface Plasmon Resonance phenomenon to produce super-resolution images with an
optical microscope equipped with a custom design polarization analyzer module.
In this paper we describe the method and apply it to the analysis of low-energy
carbon ion tracks implanted in a nuclear emulsion film. The result is then
compared with the measurements of the same tracks carried out at an electronic
microscope. The images set side by side show their close similarity. The
resolution achieved with the current microscope setup is estimated to be about
50 nm.Comment: 13 pages, 10 figure
Eicosapentaenoic Acid Intake Associated with Reduced Risk of Posttraumatic Stress Disorder after the Great East Japan Earthquake and Tsunami
Posttraumatic stress disorder (PTSD) is a debilitating condition characterized by intrusion, avoidance, hyperarousal symptoms after exposure to traumatic events. Since polyunsaturated fatty acids (PUFAs) have been implicated, we examined the possible association of PTSD with plasma PUFA level and dietary fish intake in 563 women who was struck by the Great East Japan Earthquake and Tsunami. The impact event scale-revised (IES-R) was used to assess PTSD symptoms. Dietary intake was estimated by a self-report questionnaire. Multivariate analysis controlling for age, body mass index, and stress revealed that PTSD status (IES-R ≥ 25) was associated with plasma eicosapentaenoic acid (EPA) level (P = 0.039). In the high-stress group, there were significantly inverse correlations of plasma EPA with IES-R total (r = −0.389, P = 0.031), intrusion (r = −0.370, P = 0.04), and hyperarousal scores (r = −0.480, P = 0.006), although such correlations were not found in the moderate-stress group. Fish intake that increased plasma EPA showed similar correlations with IES-R scores in the severely stressed group. Our results suggest that higher plasma EPA level and EPA-increasing fish intake are associated with a lower risk for PTSD in individuals who have suffered severe stress in a natural disaster
Polyphenols in lahpet-so and two new catechin metabolites produced by anaerobic microbial fermentation of green tea
The phenolic constituents of lahpet-so, a traditional postfermented tea of Myanmar produced under anaerobic conditions, were examined. The major polyphenols were identified to be pyrogallol and 4′-hydroxyphenyl-3- (2′′,4′′,6′′-trihydroxyphenyl)-propan-2-ol, 3′,4′-dihydroxyphenyl-3-(2′′,4′′, 6′′-trihydroxyphenyl)-propan-2-ol, and 3′,4′,5′- trihydroxyphenyl-3-(2′′,4′′,6′′- trihydroxyphenyl)-propan-2-ol. The hydroxydiphenylpropan-2-ols were identical to the initial metabolites produced from green tea catechins by mammalian intestinal bacteria. In addition, an anaerobic mixed-fermentation experiment using lahpet-so and Japanese commercial green tea afforded two new catechin degradation products together with known compound bruguierol B and the above-mentioned catechin metabolites. Based on spectroscopic evidence, the structures of the new compounds were concluded to be 4-(2,5-dihydroxyhexyl) benzene-1,2-diol and (5S,8R)-6,7,8,9-tetrahydro-5-methyl-5・8-epoxy-5H- benzocycloheptene-2,3,4-triol. Interestingly, the production mechanism was deduced to be the inverse of the biosynthesis of the flavan-3-ol A ring
Prevalence of childhood obstructive sleep apnea syndrome and its role in daytime sleepiness
ObjectivesTo investigate childhood obstructive sleep apnea syndrome (OSAS) and its role in daytime sleepiness among school-age children.MethodsA questionnaire survey was conducted with 25,211 children aged 6–15 (mean, 10.39) years attending 148 elementary and 71 middle schools in 10 prefectures across Japan and their parents. Questions concerned 4 sleep habit items (bedtime, sleep onset latency, wake time after sleep onset, wake-up time) and 4 sleep disorder items (loud snoring, snorts/gasps, breathing pauses, seems very sleepy in the daytime). Total sleep time (TST) was calculated with sleep habits. Severe possible OSAS (p-OSAS) was defined as having loud snoring, snorts and gasps, or breathing pauses “frequently” (≥ 5 times per week), and mild p-OSAS was rated as having any of these “sometimes” (2–4 times per week). Severe daytime sleepiness was defined as seeming very sleepy “frequently” and mild daytime sleepiness as seeming very sleepy “sometimes”.ResultsMean prevalence of mild to severe p-OSAS and severe p-OSAS in children across all grade levels was 9.5% and 1.6%, respectively. p-OSAS was particularly prevalent in children at lower elementary levels, decreasing with advancing grade levels. Prevalence of mild and severe daytime sleepiness was 6.1% and 0.9%, respectively, among all children (7.0%). Prevalence of daytime sleepiness increased with advancing grade levels, particularly in middle-school level. Average TST was 8.4 ± 2.2 h in both elementary and middle-school levels, and decreased as grades advanced, particularly in middle-school levels. Multivariate logistic regression analysis showed that middle-school level, TST < 8 h, and p-OSAS were independent factors for daytime sleepiness. Strong correlations were found between severe daytime sleepiness and severe p-OSAS or TST < 6 h, and between daytime sleepiness and loud snoring or breathing pauses.Conclusionp-OSAS may be an independent factor influencing daytime sleepiness in school-age children. Loud snoring and breathing pauses could be clinical markers for children with severe daytime sleepiness
Insight into the origin of carbon corrosion in positive electrodes of supercapacitors
While activated carbons are used as electrode materials in commercial supercapacitors, they are not stable under high voltage operation especially at a positive-electrode side, and this limits the working voltage of supercapacitors to about 2.8 V in organic electrolytes. Thus, revealing the specific carbon chemical structures causing the corrosion is of great significance to come up with ideas of avoiding the corrosion reactions and eventually to achieve high energy density by expanding the working voltage. In this work, a variety of carbon materials are analyzed with many characterization techniques such as X-ray diffraction, Raman spectroscopy, N2 adsorption, magnetic susceptibility measurement, and temperature programmed desorption up to 1800 °C, to find out the origin of corrosion reactions in an organic electrolyte. While carbon crystallinity and porosity are not directly related to the positive-electrode corrosion, a good correlation is found between the corrosion charge and the number of carbon edge sites terminated by H and oxygen-functional groups which are decomposed and release CO. It is thus concluded that the H-terminated edge sites, phenol, ether and carbonyl groups are electroactive sites for the carbon materials used in the positive electrode of supercapacitors.This work was supported by JSPS KAKENHI (grant no. 15H01999 and 17H01042); the Dynamic Alliance for Open Innovation Bridging Human, Environment, and Materials program; and the Network Joint Research Centre for Materials and Devices. R. T. acknowledges the China Scholarship Council for the financial support. MINECO and FEDER (CTQ2015-66080-R MINECO/FEDER) are acknowledged for financial support
Different impressions of other agents obtained through social interaction uniquely modulate dorsal and ventral pathway activities in the social human brain
Internal (neuronal) representations in the brain are modified by our experiences, and this phenomenon is not unique to sensory and motor systems. Here, we show that different impressions obtained through social interaction with a variety of agents uniquely modulate activity of dorsal and ventral pathways of the brain network that mediates human social behavior.
We scanned brain activity with functional magnetic resonance imaging (fMRI) in 16 healthy volunteers when they performed a simple matching-pennies game with a human, human-like android, mechanical robot, interactive robot, and a computer. Before playing this game in the scanner, participants experienced social interactions with each opponent separately and scored their initial impressions using two questionnaires.
We found that the participants perceived opponents in two mental dimensions: one represented “mind-holderness” in which participants attributed anthropomorphic impressions to some of the opponents that had mental functions, while the other dimension represented “mind-readerness” in which participants characterized opponents as intelligent. Interestingly, this “mind-readerness” dimension correlated to participants frequently changing their game tactic to prevent opponents from envisioning their strategy, and this was corroborated by increased entropy during the game. We also found that the two factors separately modulated activity in distinct social brain regions. Specifically, mind-holderness modulated activity in the dorsal aspect of the temporoparietal junction (TPJ) and medial prefrontal and posterior paracingulate cortices, while mind-readerness modulated activity in the ventral aspect of TPJ and the temporal pole.
These results clearly demonstrate that activity in social brain networks is modulated through pre-scanning experiences of social interaction with a variety of agents. Furthermore, our findings elucidated the existence of two distinct functional networks in the social human brain. Social interaction with anthropomorphic or intelligent-looking agents may distinctly shape the internal representation of our social brain, which may in turn determine how we behave for various agents that we encounter in our society
Case Report Ovarian Seromucinous Borderline Tumor and Clear Cell Carcinoma: An Unusual Combination
Ovarian seromucinous borderline tumors (SMBTs) are rare. They architecturally resemble serous borderline tumors but are much more frequently associated with endometriosis. The coexistence of other tumors with seromucinous tumors is also extremely rare. Here, we report an unusual combination of bilateral ovarian SMBT and clear cell carcinoma associated with polypoid endometriosis of the colon, in a 62-year-old woman. There was no transitional lesion between the two tumors. Immunohistochemistry showed different staining patterns in tumor components. Seromucinous tumor cells were positive for estrogen receptor (ER) and progesterone receptor (PgR) but negative for Napsin A, p504S, and HNF1B. Clear cell tumor cells were positive for Napsin A and p504S and focally positive for HNF1B but negative for ER and PgR. Loss of ARID1A expression was not observed in SMBTs, clear cell tumors, or endometriosis. These findings suggest that these tumors arose from separate endometriosis foci and collided within the same ovary. To the best of our knowledge, this is the first case of this unusual combination of ovarian seromucinous tumor and clear cell carcinoma to be reported in the English literature
Failure of DNA double-strand break repair by tau mediates Alzheimer’s disease pathology in vitro
DNA double-strand break (DSB) is the most severe form of DNA damage and accumulates with age, in which cytoskeletal proteins are polymerized to repair DSB in dividing cells. Since tau is a microtubule-associated protein, we investigate whether DSB is involved in tau pathologies in Alzheimer’s disease (AD). First, immunohistochemistry reveals the frequent coexistence of DSB and phosphorylated tau in the cortex of AD patients. In vitro studies using primary mouse cortical neurons show that non-p-tau accumulates perinuclearly together with the tubulin after DSB induction with etoposide, followed by the accumulation of phosphorylated tau. Moreover, the knockdown of endogenous tau exacerbates DSB in neurons, suggesting the protective role of tau on DNA repair. Interestingly, synergistic exposure of neurons to microtubule disassembly and the DSB strikingly augments aberrant p-tau aggregation and apoptosis. These data suggest that DSB plays a pivotal role in AD-tau pathology and that the failure of DSB repair leads to tauopathy
- …