Preparation and Characterization of Thermoelectric PEDOT/Te Nanorod Array Composite Films.

In this study, we prepared Te nanorod arrays via a galvanic displacement reaction (GDR) on a Si wafer, and their composite with poly(3,4-ethylenedioxythiophene) (PEDOT) were successfully synthesized by electrochemical polymerization with lithium perchlorate (LiClO4) as a counter ion. The thermoelectric performance of the composite film was optimized by adjusting the polymerization time. As a result, a maximum power factor (PF) of 235 µW/mK2 was obtained from a PEDOT/Te composite film electrochemically polymerized for 15 s at room temperature, which was 11.7 times higher than that of the PEDOT film, corresponding to a Seebeck coefficient (S) of 290 µV/K and electrical conductivity (σ) of 28 S/cm. This outstanding PF was due to the enhanced interface interaction and carrier energy filtering effect at the interfacial potential barrier between the PEDOT and Te nanorods. This study demonstrates that the combination of an inorganic Te nanorod array with electrodeposited PEDOT is a promising strategy for developing high-performance thermoelectric materials.

Facial Fabrication and Characterization of Novel Ag/AgCl Chloride Ion Sensor Based on Gel-Type Electrolyte.

In this study, a novel chloride ion (Cl-) sensor based on Ag wire coated with an AgCl layer was fabricated using a gel-type internal electrolyte and a diatomite ceramic membrane, which played an important role in preventing electrolyte leakage from the ion-selective electrode. The sensing performance, including reversibility, response, recovery time, low detection limit, and the long-term stability, was systemically investigated in electrolytes with different Cl- contents. The as-fabricated Cl- sensor could detect Cl- from 1 to 500 mM KCl solution with good linearity. The best response and recovery time obtained for the optimized sensor were 0.5 and 0.1 s, respectively, for 10 mM KCl solution. An exposure period of over 60 days was used to evaluate the stability of the Cl- sensor in KCl solution. A relative error of 2% was observed between the initial and final response potentials. Further, a wireless sensing system based on Arduino was also investigated to measure the response potential of Cl- in an electrolyte. The sensor exhibited high reliability with a low standard error of measurement. This type of sensor is crucial for fabricating wireless Cl- sensors for applications in reinforced concrete structures along with favorable performances.

Senescence-related functional nuclear barrier by down-regulation of nucleo-cytoplasmic trafficking gene expression.

One of the characteristic natures of senescent cells is the hypo- or irresponsiveness not only to growth factors but also to apoptotic stress. In the present study, we confirmed the inhibition of nuclear translocation of activated p-ERK1/2 and NF-kB p50 in response to growth stimuli or LPS in the senescent human diploid fibroblasts. In order to elucidate the underlying mechanism for the senescence-associated hypo-responsiveness, we carried out the comparison study for gene expression profiles through microarray analysis. In consequence, we observed the vast reduction in expression of nucleo-cytoplasmic trafficking genes in senescent cells, when compared with those in young cells. Expression levels of several nucleoporins, karyopherin alpha, karyopherin beta, Ran, and Ran-regulating factors were confirmed to be down-regulated in senescent HDFs by using RT-PCR and Western blot methods. Taken together, these data suggest the operation of certain senescence-associated functional nuclear barriers by down-regulation of the nucleo-cytoplasmic trafficking genes in the senescent cells.

Perilla leaf, Perilla frutescens, induces apoptosis and G1 phase arrest in human leukemia HL-60 cells through the combinations of death receptor-mediated, mitochondrial, and endoplasmic reticulum stress-induced pathways.

Since it has been reported that Perilla leaves (Perilla frutescens) have antimutagenic, antioxidant, and anti-inflammatory properties, we hypothesized that Perilla leaves may have a potential anticancer activity. Therefore, we examined the possibility that cancer cell growth is reduced by treatment with a Perilla leaf ethanol extract (PLE) using human leukemia HL-60 cells and then investigated the mechanism of the growth inhibition. We found that PLE treatment suppressed cell viability in a dose-dependent manner. Flow cytometric analysis revealed that PLE treatment caused the appearance of a sub-G1 DNA peak and induced cell cycle arrest at the G1 phase. We detected DNA ladders in PLE-treated cells by agarose gel electrophoresis, and the cleavage of pro-caspase-3 and poly(ADP-ribose) polymerase with remarkable activation of caspase-8, -9, and -3. Western blot analysis revealed dose-dependent increases in Bax and cytochrome c in cytosol fractions and decreased Bid and pro-caspase-8 and -3 in PLE-treated cells. In addition, glucose-regulated protein 78, phosphorylated eukaryotic translation initiation factor 2 subunit alpha, phosphorylated c-jun N-terminal kinase, and p21 levels were increased by PLE treatment in a dose-dependent manner, whereas the p27 level was not changed. We concluded that PLE induced apoptosis through the combinations of mitochondrial, death receptor-mediated, and endoplasmic reticulum pathways and suppressed the cell proliferation via p21-mediated G1 phase arrest in HL-60 cells.