Graphite-based selectorless RRAM: improvable intrinsic nonlinearity for array applications

Chen, Ying-Chen,Hu, Szu-Tung,Lin, Chih-Yang,Fowler, Burt,Huang, Hui-Chun,Lin, Chao-Cheng,Kim, Sungjun,Chang, Yao-Feng,Lee, Jack C. The Royal Society of Chemistry 2018 Nanoscale Vol.10 No.33

<P>Selectorless graphite-based resistive random-access memory (RRAM) has been demonstrated by utilizing the intrinsic nonlinear resistive switching (RS) characteristics, without an additional selector or transistor for low-power RRAM array application. The low effective dielectric constant value (<I>k</I>) layer of graphite or graphite oxide is utilized, which is beneficial in suppressing sneak-path currents in the crossbar RRAM array. The tail-bits with low nonlinearity can be manipulated by the positive voltage pulse, which in turn can alleviate variability and reliability issues. Our results provide additional insights for built-in nonlinearity in 1<I>R</I>-only selectorless RRAMs, which are applicable to the low-power memory array, ultrahigh density storage, and in-memory neuromorphic computational configurations.</P>

Preparation and characterization of Y-TZP powders coated with alumina

Chih-Cheng Chen,Shu-Wei Hsu,Hsing-I Hsiang 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.2

In this study, alumina was coated onto yttria tetragonally stabilized zirconia (Y-TZP)core powder using aluminum nitrate with urea in an aqueous solution. Boehmite coating onto the surface of Y-TZP powders was confirmed using transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy and zeta potential measurements. The sintering behaviors of Y-TZP powders with and without an alumina coating were investigated using a dilatometer and scanning electron microscopy (SEM). Boehmite coating onto the surface of Y-TZP powders significantly improved the densification of the resulting ceramic bodies. The relative density of the Y-TZP with a boehmite coating sintered at 1350oC can reach 97.3%. In this study, alumina was coated onto yttria tetragonally stabilized zirconia (Y-TZP)core powder using aluminum nitrate with urea in an aqueous solution. Boehmite coating onto the surface of Y-TZP powders was confirmed using transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy and zeta potential measurements. The sintering behaviors of Y-TZP powders with and without an alumina coating were investigated using a dilatometer and scanning electron microscopy (SEM). Boehmite coating onto the surface of Y-TZP powders significantly improved the densification of the resulting ceramic bodies. The relative density of the Y-TZP with a boehmite coating sintered at 1350oC can reach 97.3%.

Cav3.2 T-Type Ca2+ Channel-Dependent Activation of ERK in Paraventricular Thalamus Modulates Acid-Induced Chronic Muscle Pain.

Chen, Wen-Kwei,Liu, Ingrid Y,Chang, Ya-Ting,Chen, Yong-Cyuan,Chen, Chih-Cheng,Yen, Chen-Tung,Shin, Hee-Sup,Chen, Chien-Chang The Society 2010 The Journal of neuroscience Vol.30 No.31

<P>Treatments for chronic musculoskeletal pain, such as lower back pain, fibromyalgia, and myofascial pain syndrome, remain inadequate because of our poor understanding of the mechanisms that underlie these conditions. Although T-type Ca(2+) channels (T-channels) have been implicated in peripheral and central pain sensory pathways, their role in chronic musculoskeletal pain is still unclear. Here, we show that acid-induced chronic mechanical hyperalgesia develops in Ca(v)3.1-deficient and wild-type but not in Ca(v)3.2-deficient male and female mice. We also show that T-channels are required for the initiation, but not maintenance, of acid-induced chronic muscle pain. Blocking T-channels using ethosuximide prevented chronic mechanical hyperalgesia in wild-type mice when administered intraperitoneally or intracerebroventricularly, but not intramuscularly or intrathecally. Furthermore, we found an acid-induced, Ca(v)3.2 T-channel-dependent activation of ERK (extracellular signal-regulated kinase) in the anterior nucleus of paraventricular thalamus (PVA), and prevention of the ERK activation abolished the chronic mechanical hyperalgesia. Our findings suggest that Ca(v)3.2 T-channel-dependent activation of ERK in PVA is required for the development of acid-induced chronic mechanical hyperalgesia.</P>

Effects of the addition of minute amounts of alumina on the microstructure and sintering behavior of yttria stabilized tetragonal zirconia polycrystals ceramic via a co-precipitation process

Chih-Cheng Chen,Chang-Min Zhou,Hsing-I Hsiang 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.3

It is feasible to add homogeneously minute amounts (0.25 wt%) of Al₂O₃ into 3 mol% yttria stabilized tetragonal zirconia polycrystals using a co-precipitation procedure to produce precursory gel nano-powders. X-ray diffraction, scanning electron microscopy, high-angle annular dark-field-field emission gun transmission electron microscopy, relative density determination, shrinkage, and resistivity measurements using impedance spectroscopy were combined to elucidate the microstructure and sintering behavior of zirconia ceramics produced using 0.25 wt% added Al₂O₃, possibly the limit of solubility of Al₂O₃ in the ZrO₂ structure. Two modes of sintering behavior may be described as: (I) The total solid solution of Al₂O₃ in the solid solution of ZrO₂ structure via a precursory co-precipitation procedure; calcining at 800 oC and sintering at 1275 oC can be shown to indicate the viable solubility of Al₂O₃ in the ZrO₂ structure, designated as stage I of the thermal treatment; and (II) At the higher sintering temperature, above 1275 oC, the segregation of Al₂O₃ at triple junction occurs. Higher bulk and grain boundary resistivity values are found for the sample sintered at 1275 oC, which probably resulted from the dissolution of Al₂O₃ in the ZrO₂ structure. It is feasible to add homogeneously minute amounts (0.25 wt%) of Al₂O₃ into 3 mol% yttria stabilized tetragonal zirconia polycrystals using a co-precipitation procedure to produce precursory gel nano-powders. X-ray diffraction, scanning electron microscopy, high-angle annular dark-field-field emission gun transmission electron microscopy, relative density determination, shrinkage, and resistivity measurements using impedance spectroscopy were combined to elucidate the microstructure and sintering behavior of zirconia ceramics produced using 0.25 wt% added Al₂O₃, possibly the limit of solubility of Al₂O₃ in the ZrO₂ structure. Two modes of sintering behavior may be described as: (I) The total solid solution of Al₂O₃ in the solid solution of ZrO₂ structure via a precursory co-precipitation procedure; calcining at 800 oC and sintering at 1275 oC can be shown to indicate the viable solubility of Al₂O₃ in the ZrO₂ structure, designated as stage I of the thermal treatment; and (II) At the higher sintering temperature, above 1275 oC, the segregation of Al₂O₃ at triple junction occurs. Higher bulk and grain boundary resistivity values are found for the sample sintered at 1275 oC, which probably resulted from the dissolution of Al₂O₃ in the ZrO₂ structure.

Effect of Landslide Deposition on Soil Properties in the Xitou Experiment Forest, Central Taiwan

Chih-Hsin Cheng,Sheng-Che Hsiao,Yu-Hsuan Huang,Chih-Yu Hung,Chuang-Wen Pai,Chiu Ping Chen,Oleg Menyailo 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Sofosbuvir/velpatasvir plus ribavirin for Child-Pugh B and Child-Pugh C hepatitis C virus-related cirrhosis

( Chen-hua Liu ),( Chi-yi Chen ),( Wei-wen Su ),( Chun-jen Liu ),( Ching-chu Lo ),( Ke-jhang Huang ),( Jyh-jou Chen ),( Kuo-chih Tseng ),( Chi-yang Chang ),( Cheng-yuan Peng ),( Yu-lueng Shih ),( Chia 대한간학회 2021 Clinical and Molecular Hepatology(대한간학회지) Vol.27 No.4

Background/Aims: Real-world studies assessing the effectiveness and safety of sofosbuvir/velpatasvir (SOF/VEL) plus ribavirin (RBV) for Child-Pugh B/C hepatitis C virus (HCV)-related cirrhosis are limited. Methods: We included 107 patients with Child-Pugh B/C HCV-related cirrhosis receiving SOF/VEL plus RBV for 12 weeks in Taiwan. The sustained virologic response rates at off-treatment week 12 (SVR₁₂) for the evaluable population (EP), modified EP, and per-protocol population (PP) were assessed. The safety profiles were reported. Results: The SVR₁₂ rates in the EP, modified EP and PP were 89.7% (95% confidence interval [CI], 82.5-94.2%), 94.1% (95% CI, 87.8-97.3%), and 100% (95% CI, 96.2-100%). Number of patients who failed to achieve SVR₁₂ were attributed to virologic failures. The SVR₁₂ rates were comparable regardless of patient characteristics. One patient discontinued treatment because of adverse events (AEs). Twenty-four patients had serious AEs and six died, but none were related to SOF/VEL or RBV. Among the 96 patients achieving SVR₁₂, 84.4% and 64.6% had improved Child-Pugh and model for endstage liver disease (MELD) scores. Multivariate analysis revealed that a baseline MELD score ≥15 was associated with an improved MELD score of ≥3 (odds ratio, 4.13; 95% CI, 1.16-14.71; P=0.02). Patients with chronic kidney disease (CKD) stage 1 had more significant estimated glomerular filtration rate declines than patients with CKD stage 2 (-0.42 mL/min/1.73 ㎡/month; P=0.01) or stage 3 (-0.56 mL/min/1.73 ㎡/month; P<0.001). Conclusions: SOF/VEL plus RBV for 12 weeks is efficacious and well-tolerated for Child-Pugh B/C HCV-related cirrhosis. (Clin Mol Hepatol 2021;27:575-588)

The feasibility of detecting endometrial and ovarian cancer using DNA methylation biomarkers in cervical scrapings

Cheng-Chang Chang,Hui-Chen Wang,Yu-Ping Liao,Yu-Chih Chen,Yu-Chun Weng,Mu-Hsien Yu,Hung-Cheng Lai 대한부인종양학회 2018 Journal of Gynecologic Oncology Vol.29 No.1

Objective: We hypothesized that DNA methylation of development-related genes may occur in endometrial cancer (EC)/ovarian cancer (OC) and may be detected in cervical scrapings. Methods: We tested methylation status by quantitative methylation-specific polymerase chain reaction for 14 genes in DNA pools of endometrial and OC tissues. Tissues of EC/normal endometrium, OC/normal ovary, were verified in training set using cervical scrapings of 10 EC/10 OC patients and 10 controls, and further validated in the testing set using independent cervical scrapings in 30 EC/30 OC patients and 30 controls. We generated cutoff values of methylation index (M-index) from cervical scrapings to distinguish between cancer patients and control. Sensitivity/specificity of DNA methylation biomarkers in detecting EC and OC was calculated. Results: Of 14 genes, 4 (PTGDR, HS3ST2, POU4F3, MAGI2) showed hypermethylation in EC and OC tissues, and were verified in training set. POU4F3 and MAGI2 exhibited hypermethylation in training set were validated in independent cases. The mean M-index of POU4F3 is 78.28 in EC and 20.36 in OC, which are higher than that in controls (6.59; p<0.001 and p=0.100, respectively), and that of MAGI2 is 246.0 in EC and 12.2 in OC, which is significantly higher that than in controls (2.85; p<0.001 and p=0.480, respectively). Sensitivity and specificity of POU4F3/MAGI2 were 83%–90% and 69%–75% for detection of EC, and 61% and 62%–69% for the detection of OC. Conclusion: The findings demonstrate the potential of EC/OC detection through testing for DNA methylation in cervical scrapings.

Effects of aging on the phase transformation and sintering properties of coprecipitated Al₂O₃-ZrO₂ powders

Chih-Cheng Chen,Hsing-I Hsiang,Fu-Su Yen 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.1

In this study, the effects of aging on the crystalline phases, crystallite sizes and sintering properties of coprecipitated Al₂O₃- ZrO₂ powders are investigated using thermogravimetry (TG), differential thermal analysis (DTA), X-ray diffractometry (XRD), dilatometry, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Coprecipitated Al₂O₃- ZrO₂ powder aging in the solution promoted the dissolution and reprecipitation process, which resulted in the boehmite structure subsequently transforming into bayerite. The densification and microstructural development of the coprecipitated Al₂O₃-ZrO₂ powders were dependent upon the aging time which shifted the θ→α-Al₂O₃ phase transformation to a higher temperature, lowered the crystallite growth rate, and prevented the occurrence of intragranular ZrO₂ particles during sintering. In this study, the effects of aging on the crystalline phases, crystallite sizes and sintering properties of coprecipitated Al₂O₃- ZrO₂ powders are investigated using thermogravimetry (TG), differential thermal analysis (DTA), X-ray diffractometry (XRD), dilatometry, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Coprecipitated Al₂O₃- ZrO₂ powder aging in the solution promoted the dissolution and reprecipitation process, which resulted in the boehmite structure subsequently transforming into bayerite. The densification and microstructural development of the coprecipitated Al₂O₃-ZrO₂ powders were dependent upon the aging time which shifted the θ→α-Al₂O₃ phase transformation to a higher temperature, lowered the crystallite growth rate, and prevented the occurrence of intragranular ZrO₂ particles during sintering.

The back contact modification in high-efficiency Cu₂ZnSn(S,Se)₄ solar cells by a thin MoO₃ layer

Septia KHOLIMATUSSADIAH,Cheng-Ying CHEN,Wei-Chao CHEN,Yi-Rung LIN,Shao-Hung LU,Meng-Chia HSIEH,Jan-Kai CHANG,Chih-I WU,Ruei-San CHEN,Kuei-Hsien CHEN,Li-Chyong CHEN 한국진공학회 2016 한국진공학회 학술발표회초록집 Vol.2016 No.8

Mesenchymal Stem Cell Secreted-Extracellular Vesicles are Involved in Chondrocyte Production and Reduce Adipogenesis during Stem Cell Differentiation

Tsai Yu-Chen,Cheng Tai-Shan,Liao Hsiu-Jung,Chuang Ming-Hsi,Chen Hui-Ting,Chen Chun-Hung,Zhang Kai-Ling,Chang Chih-Hung,Lin Po-Cheng,Huang Chi-Ying F. 한국조직공학과 재생의학회 2022 조직공학과 재생의학 Vol.19 No.6

BACKGROUND: Extracellular vesicles (EVs) are derived from internal cellular compartments, and have potential as a diagnostic and therapeutic tool in degenerative disease associated with aging. Mesenchymal stem cells (MSCs) have become a promising tool for functional EVs production. This study investigated the efficacy of EVs and its effect on differentiation capacity. METHODS: The characteristics of MSCs were evaluated by flow cytometry and stem cell differentiation analysis, and a production mode of functional EVs was scaled from MSCs. The concentration and size of EVs were quantitated by Nanoparticle Tracking Analysis (NTA). Western blot analysis was used to assess the protein expression of exosomespecific markers. The effects of MSC-derived EVs were assessed by chondrogenic and adipogenic differentiation analyses and histological observation. RESULTS: The range of the particle size of adipose-derived stem cells (ADSCs)- and Wharton’s jelly -MSCs-derived EVs were from 130 to 150 nm as measured by NTA, which showed positive expression of exosomal markers. The chondrogenic induction ability was weakened in the absence of EVs in vitro. Interestingly, after EV administration, type II collagen, a major component in the cartilage extracellular matrix, was upregulated compared to the EV-free condition. Moreover, EVs decreased the lipid accumulation rate during adipogenic induction. CONCLUSION: The results indicated that the production model could facilitate production of effective EVs and further demonstrated the role of MSC-derived EVs in cell differentiation. MSC-derived EVs could be successfully used in cell-free therapy to guide chondrogenic differentiation of ADSC for future clinical applications in cartilage regeneration.