Thermal conductivity of liquid/carbon nanotube core-shell nanocomposites

Hollow carbon nanotubes (CNTs) were impregnated with an ionic liquid, resulting in a composite core-shell nanostructure. Liquid infusion was verified by transmission electron microscopy and rigorous observations unveiled that the nanocomposite is stable, i.e., liquid did not evaporate owing to its low vapor pressure. A series of individual nanostructures were attached on T-type heat sensors and their thermal behavior was evaluated. The liquid core was found to reduce the thermal conductivity of the base structure, CNT, from ca. 28 W/mK to ca. 15 W/mK. These findings could contribute to a better understanding of nanoscale thermal science and potentially to applications such as nanodevice thermal management and thermoelectric devices

Superstable Ultrathin Water Film Confined in a Hydrophilized Carbon Nanotube

Fluids confined in a nanoscale space behave differently than in the bulk due to strong interactions between fluid molecules and solid atoms. Here, we observed water confined inside "open" hydrophilized carbon nanotubes (CNT), with diameter of tens of nanometers, using transmission electron microscopy (TEM). A 1-7 nm water film adhering to most of the inner wall surface was observed and remained stable in the high vacuum (order of 10(-5) Pa) of the TEM. The superstability of this film was attributed to a combination of curvature, nanoroughness, and confinement resulting in a lower vapor pressure for water and hence inhibiting its vaporization. Occasional, suspended ultrathin water film with thickness of 3-20 nm were found and remained stable inside the CNT. This film thickness is 1 order of magnitude smaller than the critical film thickness (about 40 nm) reported by the Derjaguin-Landau-Verwey-Overbeek theory and previous experimental investigations. The stability of the suspended ultrathin water film is attributed to the additional molecular interactions due to the extended water meniscus, which balances the rest of the disjoining pressures

Generation of a time-bin Greenberger--Horne--Zeilinger state with an optical switch

Multipartite entanglement is a critical resource in quantum information processing that exhibits much richer phenomenon and stronger correlations than in bipartite systems. This advantage is also reflected in its multi-user applications. Although many demonstrations have used photonic polarization qubits, polarization-mode dispersion confines the transmission of photonic polarization qubits through an optical fiber. Consequently, time-bin qubits have a particularly important role to play in quantum communication systems. Here, we generate a three-photon time-bin Greenberger-Horne-Zeilinger (GHZ) state using a 2 x 2 optical switch as a time-dependent beam splitter to entangle time-bin Bell states from a spontaneous parametric down-conversion source and a weak coherent pulse. To characterize the three-photon time-bin GHZ state, we performed measurement estimation, showed a violation of the Mermin inequality, and used quantum state tomography to fully reconstruct a density matrix, which shows a state fidelity exceeding 70%. We expect that our three-photon time-bin GHZ state can be used for long-distance multi-user quantum communication.Comment: 8 pages, 4 figures, 1 tabl

High Glucose Induces Severe Periodontitis.

Background/Aims: Diabetic patients are susceptible to severe periodontitis, but the precise mechanism is not fully understood. Aim of this study was to explore the biological pathogenesis of severe periodontitis in diabetic patients focusing on the crosstalk of human gingival fibroblasts (HGFs) and macrophages. Methods: A total of 70 periodontitis patients with or without diabetes mellitus (DM) were enrolled, and the statistical relationships of diabetic conditions to the periodontal inflammatory parameters were examined by cross-sectional study. In in vitro study, HGFs cell line CRL-2014® (ATCC) and differentiated THP-1 macrophages were cultured with normal glucose (NG: 5.5 mM) or high glucose (HG: 25 mM) condition, and treated with indicated inflammatory factors such as calprotectin (CPT), interleukin (IL)-1β and IL-6. To examine the effects of HG on soluble IL-6 receptor (sIL-6R) production in THP-1 macrophages, the supernatants were collected and the sIL-6R levels were measured by ELISA. To examine the effects of HG on IL-1β or IL-6-induced matrix metalloproteinase (MMPs) production in HGFs, the supernatants were collected. Levels of MMP-1 and tissue inhibitor of MMP-1 (TIMP-1) were measured by ELISA. Finally, after conditioned medium (CM) from THP-1 macrophages cultured with NG or HG conditions was collected, HGFs were treated with the CM. The supernatants were collected 24 hours later and the levels of MMP-1 and TIMP-1 were measured. To examine the specific effects of IL-1β contained in CM on MMP-1 and TIMP-1 production in HGFs, IL-1 receptor antagonist (IL-1ra) was used. Results: There were statistical correlation between IL-1β and sIL-6R levels in gingival crevicular fluid (GCF) and HbA1c in periodontitis patients with DM (IL-1β: P=0.035, sIL-6R: P=0.040). HG and CPT significantly induced sIL-6R production in THP-1 macrophages. HG significantly enhanced IL-1β or IL-6/sIL-6R-induced MMP-1 production in HGFs. The increase of MMP-1 by both IL-1β and IL-6/sIL-6R was significantly inhibited by specific ERK or IκB inhibitors. Corresponding to the regulation of MMP-1 production, HG condition increased the phosphorylation of p44/42 MAPK and IκBα in HGFs treated with IL-1β or IL-6/sIL-6R. Finally, MMP-1 production in HGFs cultured with HG increased significantly by CM from THP-1 macrophages cultured with HG. The induction of MMP-1 by the CM from THP-1 macrophages cultured with HG was significantly inhibited by dose dependent of IL-1ra in HGFs cultured with HG. Conclusion: Diabetic conditions such as HG induce IL-1β and sIL-6R production from macrophages in inflammatory periodontal tissues and may exacerbate the periodontitis synergistically via MMP-1 production from HGFs

AGEs increase lipocalin 2 expression

Background and Objectives: Diabetes mellitus (DM), a risk factor of periodontal diseases, exacerbates the pathological condition of periodontitis. A major factor for DM complications is advanced glycation end-products (AGEs) that accumulate in periodontal tissues and cause inflammatory events. Lipocalin 2 (LCN2) is an antimicrobial peptide and inflammation-related factor, and LCN2 levels increase in DM. In the present study, the effects of AGEs and lipopolysaccharide of Porphyromonas gingivalis (P.g-LPS) on LCN2 expression in human oral epithelial cells (TR146 cells) and the role of secreted LCN2 in periodontitis with DM were investigated. Material and Methods: TR146 cells were cultured with AGEs (AGE2) and control BSA and cell viability was estimated, or with P.g-LPS. Conditioned medium and cell lysates were prepared from cultures of epithelial cells and used for western blotting and ELISA to analyze LCN2, RAGE, IL-6, MAPK and NF-κB. RNA was isolated from AGE-treated TR146 cells and differentiated HL-60 (D-HL-60) cells and used for quantitative real-time PCR to examine the expression of LCN2 and interleukin-6 (IL-6) mRNAs. RAGE- and LCN2-siRNAs (siRAGE, siLCN2) were transfected into epithelial cells, and AGE-induced LCN2 expression was investigated. D-HL-60 cells were co-cultured with TR146 cells that were transfected with siLCN2 and treated with AGEs, IL-6 mRNA expression in D-HL-60 cells and cell migration were investigated. Results: AGEs increased the expression levels of LCN2 and IL-6 in oral epithelial cells. siRAGE and a neutralizing antibody for RAGE inhibited AGE-induced LCN2 expression. AGEs stimulated the phosphorylation of ERK, p38 and NF-kB in epithelial cells, and their inhibitors suppressed AGE-induced LCN2 expression. In contrast, P.g-LPS did not show a significant increase on LCN2 level in TR146 cells that expressed toll-like receptor 2. In co-culture experiments, AGE-induced LCN2 inhibited IL-6 mRNA expression in D-HL-60 cells, and LCN2 knockdown in epithelial cells suppressed HL-60 cell migration. Conclusion: These results suggested that AGEs increase LCN2 expression via RAGE, MAPK, and NF-κB signaling pathways in oral epithelial cells, and secreted LCN2 may influence the pathological condition of periodontitis with DM

健常成人の対側,同側および両側眼への閃光刺激によるVEPの差異

Differences among VEPs evoked by left and right monocular, and binocular flash stimuli were studied with 40 healthy male subjects (21-33 y.o.). VEPs were evoked by LED flash stimuli and derived from the six derivations and recorded with 1024 msec of analysis time. The following results were obtained. 1) In all of six derivations, the contours of the group mean VEPs were roughly similar in both ipsilateral left monocular and contralateral right monocular stimuli. These findings demonstrate that response characteristics and receptive field properties of the two eyes are well coincided with each other. 2) In details, the latencies of the short and middle latency components of the third (O 1→T 5) and the forth derivation (O 1→Cz) in contralateral right monocular VEPs were significantly shorter than those in ipsilateral left monocular VEPs. In all derivations, the peak to peak amplitudes in contralateral right monocular VEPs were significantly larger than those in ipsilateral left monocular VEPs. These findings verified the hemispheric dominant laterality of the contralateral eye, even with latencies, besides with amplitudes. 3) As compared with left monocular VEPs, the latencies of the short and middle latency components in binocular VEPs were significantly short and the peak to peak amplitudes in binocular VEPs were significantly large. These findings might suggest the existence of "binocular depth cells" of the monkey, which respond when the two eyes stimulated simultaneously, even in man. 4) In details, the latencies of the long latency components in binocular and contralateral right monocular VEPs were significantly longer than those in ipsilateral left monocular VEPs. This finding suggests the delay of the alpha regeneration as a photic after discharge following VEPs, because binocular and contralateral right monocular stimuli are stronger than ipsilateral left monocular stimuli

The acute effects of mianserin hydrochloride and sodium valproate on the human VEP (Visual Evoked Potential) and EEG

The acute effects of mianserin hydrochloride (MSR) and sodium valproate (VPA) were studied by visual evoked potential (VEP), with 16 healthy male subjects (26~43 y. o.). In the two experimental session on different days, MSR (0.3 mg/kg) or VPA (5 mg/kg) were orally administered for each subjects. EEGs containing VEPs evoked by flash stimuli once every 5 sec were derived from the two derivations (2ch : 01→A1+2, 5ch : 01→Cz) and recorded into magnetic tape. Reproducing the tape, VEPs with 1024 msec of analysis time were obtained by averaging 100 responses, and EEGs were subjected to the frequency ayalysis. In the experimental session, EEG containing VEPs were recorded before and 60, 120, and 180 min after the administration of MSR, and before and 30, 60, and 90 min after VPA. Consecutive change of group mean VEP were studied. Individual VEPs were subjected to the component analysis, and to the statistical assessment together with EEG. The following results were obtained. 1. After the administration of MSR, P3 and N3 latencies of the short latency components of VEP significantly increased. And most of those of long latency components (N6~) significantly increased. The peak-to-peak amplitude P3-N3 and N3-P4 significantly decreased. In EEG, the power % of δ, θ and β2 frequency band increased, and that of α2 decreased. Significant positive correlation was found between δ and θ power % of EEG and latencies and amplitudes of VEP, and significant negative correlation was found between α2 and β2 power % and latencies and amplitudes. These findings indicate the inhibitory effect of MSR mainly on the lateral geniculate body and the optic radiation in the visual system. 2. After the administration of VPA, latencies of the long latency components (P7~) of VEP sigificantly increased, but those of short latency components did not change significantly. The peak-to-peak amplitudes inconsistently decreased mainly in the short latency components. In EEG, the power % of θ frequency band increased and that of β2 decreased. Significant positive correlation was found between δ and θ power % of EEG and latencies of VEP mainly in the long latency components (P7~), and significant negative correlation was found between δ and θ power % of EEG and amplitudes of VEP mainly in the long latency components (P6~). These findings indicate the inhibitory effect of VPA mainly on the cerebral cortex through GABA neuron system

AEPおよび脳波に対するcaffeineの効果

We studied the effects of caffeine on the central nervous system by auditory evoked potentials (AEP) with 25 healthy male subjects (T-group: 24-44 y.o., mean caffeine consumption: 251.4 mg/day). According to the DSM-IV criteria for caffeine intoxication, T-group were devided into the light (L-group: 11 subjects, ≦250 mg/ day) and heavy consumer group (H-group: 14 subjects, >250 mg/ day), and into caffeine (CAF-group) and placebo administration group (PLA-group) according to a double-blind cross-over design. EEG containing AEP was recorded through the two deviations (monopolar : Cz→A1+2, bipolar : Cz→T5); before and 30, 60 and 90 min after the oral administration of caffeine or placebo (3 mg/kg of B.W.). Consecutive changes of the latencies and amplitudes in group mean AEP were studied. Those of individual AEP were subjected to the component analysis, and to the statistical assessment with reference to the EEG power % changes. 1. After the administration of caffeine, CAF-group had a significant decrease in N 4 (= N 1, latency : 95-125 msec) and P 5 (=P 2, latency : 160-200 msec) latencies of long latency components, followed by a decrease in N 4-P 5 amplitudes of AEP, which indicated that there was a post-exciting inhibitory effect in CAF(H)-group. In EEG, α power % significantly increased, whereas δ, θ and β power % significantly decreased. These findings indicated that caffeine might have a sedative effect as well as the exciting effects on the primary and secondary auditory cortex. 2. CAF(H)-group had significant changes in latencies of AEP and EEG only 30 min after the administration of caffeine, whereas CAF(L)-group had these changes over 60 min after that, suggesting the hypersensitivity to caffeine by the interruption of caffeine consumption. 3. These changes seemed to be assciated with the effects of caffeine as an adenosine A1 receptor antagonist in the cerebral cortex, although further investigation on the neurotransmitters related to caffeine should be expected