11 research outputs found
Wafer-Scale Microwire Transistor Array Fabricated via Evaporative Assembly
One-dimensional (1D) nano/microwires
have attracted significant attention as promising building blocks
for various electronic and optical device applications. The integration
of these elements into functional device networks with controlled
alignment and density presents a significant challenge for practical
device applications. Here, we demonstrated the fabrication of wafer-scale
microwire field-effect transistor (FET) arrays based on well-aligned
inorganic semiconductor microwires (indium-gallium-zinc-oxide (IGZO))
and organic polymeric insulator microwires fabricated via a simple
and large-area evaporative assembly technique. This microwire fabrication
method offers a facile approach to precisely manipulating the channel
dimensions of the FETs. The resulting solution-processed monolithic
IGZO microwire FETs exhibited a maximum electron mobility of 1.02
cm<sup>2</sup> V<sup>–1</sup> s<sup>–1</sup> and an
on/off current ratio of 1 × 10<sup>6</sup>. The appropriate choice
of the polymeric microwires used to define the channel lengths enabled
fine control over the threshold voltages of the devices, which were
employed to fabricate high-performance depletion-load inverters. Low-voltage-operated
microwire FETs were successfully fabricated on a plastic substrate
using a high-capacitance ion gel gate dielectric. The microwire fabrication
technique involving evaporative assembly provided a facile, effective,
and reliable method for preparing flexible large-area electronics
Metallic Grid Electrode Fabricated via Flow Coating for High-Performance Flexible Piezoelectric Nanogenerators
Transparent conducting electrodes
(TCEs) based on metallic grid structures have been extensively explored
for use in flexible and transparent electronics according to their
excellent conductivity and flexibility. Previous fabrication methods
have been limited by the complexity and expense of their processes.
Here, we have introduced a simple and cost-effective flow-coating
method for preparing flexible and transparent metallic grid electrodes
using silver nanoparticles (AgNPs). The process comprises only two
steps, including patterning and sintering the horizontal AgNPs lines,
followed by patterning and sintering the longitudinal AgNPs lines.
The grid width could be easily controlled by varying the concentration
of the AgNP solution and the grid spacing could be controlled by varying
the distance moved by a translation stage between intermittent stops.
The optimized Ag grid electrode exhibited an optical transmittance
at 550 nm of 86% and a sheet resistance of 174 Ω/sq. The resulting
Ag grid electrodes were successfully used to prepare a flexible piezoelectric
nanogenerator. This device showed good performance, including an output
voltage of 5 V and an output current density of 0.5 μA/cm<sup>2</sup>
Flexible and Transparent Metallic Grid Electrodes Prepared by Evaporative Assembly
We propose a novel approach to fabricating
flexible transparent
metallic grid electrodes via evaporative deposition involving flow-coating.
A transparent flexible metal grid electrode was fabricated through
four essential steps including: (i) polymer line pattern formation
on the thermally evaporated metal layer onto a plastic substrate;
(ii) rotation of the stage by 90° and the formation of the second
polymer line pattern; (iii) etching of the unprotected metal region;
and (iv) removal of the residual polymer from the metal grid pattern.
Both the metal grid width and the spacing were systematically controlled
by varying the concentration of the polymer solution and the moving
distance between intermittent stop times of the polymer blade. The
optimized Au grid electrodes exhibited an optical transmittance of
92% at 550 nm and a sheet resistance of 97 Ω/sq. The resulting
metallic grid electrodes were successfully applied to various organic
electronic devices, such as organic field-effect transistors (OFETs),
organic light-emitting diodes (OLEDs), and organic solar cells (OSCs)
Combined EGCG/As treatment increases apoptosis in BAEC.
<p>(A) BAEC were treated with various doses (0, 5, 10, 20, 30, or 40 μM) of As or EGCG for 24 h. (B) In some experiments, cells were also treated for 24 h with 20 μM EGCG, 20 μM As, or the combination of 20 μM EGCG and As each (EGCG/As). (A, B) Cell viability was measured using MTT assay. (C, D) Cells treated with EGCG, As, or EGCG/As for 12 h. (C) Apoptotic cells were detected by DAPI staining. (D) Cells were lysed in RIPA buffer. An equal amount (20 μg) of each cell lysate was subjected to Western blot analysis. Levels of cleaved PARP expression were detected with an anti-cleaved PARP antibody. Quantifications were performed using densitometry (Image J software) and results were normalized to β-actin. (E-G) The activity of caspases (3, 8, and 9) was measured in cells treated with EGCG, As or EGCG/As for the specified times (0, 6, 12, 18, or 24 h). All line graphs represent the relative caspase activity of the control. (H) Assay for Bax translocation into the mitochondria. Cells treated with EGCG, As, or EGCG/As for 12 h were stained with FITC-conjugated anti-Bax antibody, Mitotracker as a marker of mitochondria, or DAPI. All bar graphs represent the mean ± S.D. of 3 independent experiments. The different characters refer to significant differences (<i>P <</i> 0.05) among groups, which were determined by one-way ANOVA followed by post hoc Student-Newman-Keuls analysis.</p
Combined EGCG/As treatment increases ROS generation and decreases the activity of catalase but not SOD.
<p>(A) ROS levels were determined by flow cytometric analysis using DCFH-DA staining. Cells were treated with EGCG, As, or EGCG/As (each 20 μM) for 3 h and then stained with DCFH-DA. Stained cells were analyzed by flow cytometry using Cellquest software. The data are representative of 3 independent experiments. (B) SOD activity was assessed in cells treated with EGCG, As, or EGCG/As (each 20 μM) for 30 min. (C) The catalase activity was measured in EC treated with EGCG, As, or EGCG/As (each 20 μM) for 2.5 h. (D) Lipid peroxidation was estimated by measuring the production of malondialdehyde (MDA) using the Colorimetric Microplate Assay for Lipid Peroxidation Kit (Oxford) according to the manufacturer’s protocol. All bar graphs represent the mean ± S.D. of 3 independent experiments. Statistical analysis was accomplished as described in the legend of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138590#pone.0138590.g001" target="_blank">Fig 1</a>.</p
NAC reverses cytotoxicity and pro-caspase activity induced by combined EGCG/As treatment.
<p>(A) BAEC were pretreated with various doses (0, 1, 5, or 10 mM) of NAC for 3 h prior to EGCG/As treatment for 24 h. (B-D) In separate experiments, EC were pretreated with the indicated dose (5 mM) of NAC. (E) In flow cytometric analysis, BAEC were pretreated with 20 μM Boc-D-FMK for 3 h prior to EGCG/As treatment for 12 h. (A) Cell viability, (B) caspase activity, (C) DAPI staining, (D) Bax translocation into the mitochondria, and (E) flow cytometric analyses were performed as described in the legend of Figs <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138590#pone.0138590.g001" target="_blank">1</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138590#pone.0138590.g002" target="_blank">2</a>. All bar graphs represent the mean ± S.D. of 3 independent experiments. Statistical analysis was accomplished as described in the legend of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138590#pone.0138590.g001" target="_blank">Fig 1</a>.</p
Catalase reverses cytotoxicity and pro-caspase activity induced by combined EGCG/As treatment.
<p>BAEC pretreated with catalase (50 U/ml) for 30 min were exposed to EGCG/As for 24 h. (A) Cell viability, (B) Western blot analysis using the indicated antibodies, and (C) Bax translocation into the mitochondria were determined as described in the legend of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138590#pone.0138590.g001" target="_blank">Fig 1</a>. All bar graphs represent the mean ± S.D. of 3 independent experiments. Statistical analysis was accomplished as described in the legend of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138590#pone.0138590.g001" target="_blank">Fig 1</a>.</p
JNK mediates catalase activity, ROS production, and apoptosis altered by combined EGCG/As treatment.
<p>(A) BAEC were treated with EGCG/As for the indicated times (0, 0.5, 1, 2, or 3 h). (B) After pretreatment with catalase (50 U/ml) or the JNK inhibitor SP600125 (1 μM) for 30 min, EC were treated with EGCG/As for 1 h. The level of phosphorylated JNK (p-JNK) and total JNK protein was detected by Western blot analysis. (C) Cells were prepared and stained as described in the legends of Fig 5A and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138590#pone.0138590.g002" target="_blank">Fig 2</a>. In some experiments, cells were pretreated as described in the legend of Fig 5B, followed by treatment with EGCG/As for 3 h. Flow cytometric analysis was performed as described in the legend of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138590#pone.0138590.g002" target="_blank">Fig 2</a>. (D) Cell viability was determined as described in the legend of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138590#pone.0138590.g001" target="_blank">Fig 1</a> using BAEC pretreated with SP600125 prior to EGCG/As treatment for 24 h. (E) Catalase activity was measured as described in the legend of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138590#pone.0138590.g002" target="_blank">Fig 2</a> using BAEC pretreated with SP600125 prior to EGCG/As treatment for 2.5 h. (F, G) Cells were prepared, and pretreated with SP600125 (F) or MG132 (20 μM) (G) for 30 min prior to treatment of EGCG/As for 2.5 h. Cell lysate (30 μg) was subjected on 10% SDS-PAGE, and the level of catalase protein was then detected as described in <b>Materials and methods</b>. All bar graphs represent the mean±S.D. of 3 independent experiments. Statistical analysis was accomplished as described in the legend of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138590#pone.0138590.g001" target="_blank">Fig 1</a>.</p
Petal-Inspired Diffractive Grating on a Wavy Surface: Deterministic Fabrications and Applications to Colorizations and LED Devices
Interestingly, the
petals of flowering plants display unique hierarchical
structures, in which surface relief gratings (SRGs) are conformably
coated on a curved surface with a large radius of curvature (hereafter
referred to as wavy surface). However, systematic studies on the interplay
between the diffractive modes and the wavy surface have not yet been
reported, due to the absence of deterministic nanofabrication methods
capable of generating combinatorially diverse SRGs on a wavy surface.
Here, by taking advantage of the recently developed nanofabrication
composed of evaporative assembly and photofluidic holography inscription,
we were able to achieve (i) combinatorially diverse petal-inspired
SRGs with controlled curvatures, periodicities, and dimensionalities,
and (ii) systematic optical studies of the relevant diffraction modes.
Furthermore, the unique diffraction modes of the petal-inspired SRGs
were found to be useful for the enhancement of the outcoupling efficiency
of an organic light emitting diode (OLED). Thus, our systematic analysis
of the interplay between the diffractive modes and the petal-inspired
SRGs provides a basis for making more informed decisions in the design
of petal-inspired diffractive grating and its applications to optoelectronics
Combined EGCG/As decreases the viability of two types of EC, HUVEC and HBMEC.
<p>(A) HUVEC were prepared and treated with various doses (0, 10, 20, 30, 40, 50 or 100 μM) of As or EGCG for 24 h. (B) In separate experiments, HUVEC were also treated with 50 μM EGCG, 10 μM As, or the combination of 50 μM EGCG and 10 μM As (EGCG/As) for 24 h. In some experiments, cells were pretreated with 5 mM NAC, 50 U/ml catalase or 1 μM SP600125 for 30 min prior to exposed to EGCG/As. (C) HBMEC were prepared and treated with various doses (0, 10, 20, 30, 40, 50 or 100 μM) of As or EGCG for 24 h. (D) In separate experiments, cells were also treated with 50 M EGCG, 50 μM As, or the combination of 50 μM EGCG and As each (EGCG/As) for 24 h. In separate experiments, cells were pretreated with 5 mM NAC, 50 U/ml catalase or 10 μM SP600125 for 30 min prior to exposed to EGCG/As. Cell viability was measured using MTT assay. All bar graphs represent the mean ± S.D. of 3–5 independent experiments. Statistical analysis was accomplished as described in the legend of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138590#pone.0138590.g001" target="_blank">Fig 1</a>.</p