Stability and electronic properties of CuAlO2 (112 0) surfaces

Cheng-Lu Jiang,Qi-Jun Liu,Fu-Sheng Liu,Zheng-Tang Liu 한국물리학회 2017 Current Applied Physics Vol.17 No.2

We have studied the stability and electronic properties of CuAlO2 ð112 『 0Þ surfaces using the firstprinciples calculations. The structural parameters, band structures, surface energies, work functions, densities of states and charge densities of CuAlO2 ð112 『 0Þ surfaces have been investigated. The calculated results show that five layers are needed to maintain convergence. After the formation of surfaces, the bandgaps of stable surfaces decrease, the covalency between Cu and O atoms in surfaces increases, and the positive charge layer in the fisrt layer appears.

Studies on Al2O3/ZrO2/Al2O3 High K Gate Dielectrics Applied in a Fully Depleted SOI MOSFET

Cheng Lu Lin,Ning Lin Zhang,Qin Wo Shen 대한금속학회 2004 METALS AND MATERIALS International Vol.10 No.5

Inhibition of L-type Ca<SUP>2+</SUP> current by ginsenoside Rd in rat ventricular myocytes

Cheng Lu,Zhijun Sun,Line Wang 고려인삼학회 2015 Journal of Ginseng Research Vol.39 No.2

Background: Ginsenoside Rd (GSRd), one of the most abundant ingredients of Panax ginseng, protects the heart via multiple mechanisms including the inhibition of Ca<SUP>2+</SUP> influx. We intended to explore the effects of GSRd on L-type Ca2+ current (ICa,L) and define the mechanism of the suppression of ICa,L by GSRd. Methods: Perforated-patch recording and whole-cell voltage clamp techniques were applied in isolated rat ventricular myocytes. Results: (1) GSRd reduced ICa,L peak amplitude in a concentration-dependent manner [half-maximal inhibitory concentration (IC50) = 32.4± 7.1 μmol/L] and up-shifted the currente-voltage (I-V) curve. (2) GSRd (30 μmol/L) significantly changed the steady-state activation curve of ICa,L (V0.5: -19.12± 0.68 vs. -16.26 ± 0.38 mV; n = 5, p < 0.05) and slowed down the recovery of ICa,L from inactivation [the time content (ζ) from 91 ms to 136 ms, n = 5, p < 0.01]. (3) A more significant inhibitive effect of GSRd (100 μmol/L) was identified in perforated-patch recording when compared with whole-cell recording [65.7 ±3.2% (n = 10) vs. 31.4 ± 5.2% (n=5), p < 0.01]. (4) Pertussis toxin (Gi protein inhibitor) completely abolished the ICa,L inhibition induced by GSRd. There was a significant difference in inhibition potency between the two cyclic adenosine monophosphate elevating agents (isoprenaline and forskolin) prestimulation [55± 7.8% (n = 5) vs. 17.2 ± 3.5% (n= 5), p < 0.01]. (5) 1H-[1,2,4]Oxadiazolo[4,3-a]-quinoxalin-1-one (a guanylate cyclase inhibitor) and N-acetyl-L-cysteine (a nitric oxide scavenger) partly recovered the ICa,L inhibition induced by GSRd. (6) Phorbol-12-myristate-13-acetate (a protein kinase Cactivator) and GF109203X (a protein kinase C inhibitor) did not contribute to the inhibition of GSRd. Conclusion: These findings suggest that GSRd could inhibit ICa,L through pertussis toxin-sensitive G protein (Gi) and a nitric oxideecyclic guanosine monophosphate-dependent mechanism.

A SUPERFICIAL FRIENDSHIP THEORY PERSPECTIVE ON INTERNATIONAL MARKET ENTRY MODE INSTABILITY AND STABILITY

Lu-Yun (Vivian) Cheng,Graça Miranda Silva 글로벌지식마케팅경영학회 2016 Global Marketing Conference Vol.2016 No.7

International Joint Venture (IJV) is one of the most popular market entry mode in emerging markets. The instability and stability of IJV have also been receiving ongoing attention in the literature (e.g. Deitz et al. 2010; Kogut 1989; Rhoades & Lush 1997; Sim & Ali 2000). IJV instability and stability are often treated as opposite to one another in the literature, and assumed the factors that account for instability has an inverse impacts on stability. However, conceptually and empirically they are not exactly two contrasting phenomena. This study adopts the perspectives of Superficial Friendship theory (Yan 2010) to differentiate the determinants of IJV instability and stability and empirically compares their determinants. The results indicate that the factors that account for instability do not have inverse impacts on stability. The empirical results not only contribute to an understanding of the different drivers of IJV instability and stability but also have important implications for international business managers in both parents and IJVs with regard to keeping an IJV profitable and successful.

The Goal of School-Based Professional Development Program for Elementary School Mathematics Teachers

Lu Pien Cheng,고호경 ( Ho Kyoung Ko ) 한국수학교육학회 2015 수학교육연구 Vol.19 No.3

The goal of this study was to examine the three components of a laboratory class cycle that empowered teachers to change their teaching practices. Six teachers and their administrator in an elementary school in the southeastern United States participated in the study. All the teachers were interviewed, and their mathematics lessons were observed at the end of each cycle of laboratory classes. The study revealed how planning, observing, and critiquing mathematics lessons as a team assisted the teachers`` learning and teaching. We identified opportunities for the teachers to experiment with different teaching approaches, and we found that support from the team and from the school were key factors for the laboratory class cycle to function effectively.

Echinacoside, an active constituent of Herba Cistanche, suppresses epileptiform activity in hippocampal CA3 pyramidal neurons

Lu, Cheng-Wei,Huang, Shu-Kuei,Lin, Tzu-Yu,Wang, Su-Jane The Korean Society of Pharmacology 2018 The Korean Journal of Physiology & Pharmacology Vol.22 No.3

Echinacoside, an active compound in the herb Herba Cistanche, has been reported to inhibit glutamate release. In this study, we investigated the effects of echinacoside on spontaneous excitatory synaptic transmission changes induced by 4-aminopyridine (4-AP), by using the in vitro rat hippocampal slice technique and whole-cell patch clamp recordings from CA3 pyramidal neurons. Perfusion with echinacoside significantly suppressed the 4-AP-induced epileptiform activity in a concentration-dependent manner. Echinacoside reduced 4-AP-induced increase in frequency of spontaneous excitatory postsynaptic currents (sEPSCs) but it did not affect the amplitude of sEPSCs or glutamate-activated currents, implicating a presynaptic mechanism of action. Echinacoside also potently blocked sustained repetitive firing, which is a basic mechanism of antiepileptic drugs. These results suggest that echinacoside exerts an antiepileptic effect on hippocampal CA3 pyramidal neurons by simultaneously decreasing glutamate release and blocking abnormal firing synchronization. Accordingly, our study provides experimental evidence that echinacoside may represent an effective pharmacological agent for treating epilepsy.

Echinacoside, an active constituent of Herba Cistanche, suppresses epileptiform activity in hippocampal CA3 pyramidal neurons

Cheng Wei Lu,Shu-Kuei Huang,Tzu Yu Lin,Su-Jane Wang 대한약리학회 2018 The Korean Journal of Physiology & Pharmacology Vol.22 No.3

Echinacoside, an active compound in the herb Herba Cistanche, has been reported to inhibit glutamate release. In this study, we investigated the effects of echinacoside on spontaneous excitatory synaptic transmission changes induced by 4-aminopyridine (4-AP), by using the in vitro rat hippocampal slice technique and whole-cell patch clamp recordings from CA3 pyramidal neurons. Perfusion with echinacoside significantly suppressed the 4-AP-induced epileptiform activity in a concentration-dependent manner. Echinacoside reduced 4-AP-induced increase in frequency of spontaneous excitatory postsynaptic currents (sEPSCs) but it did not affect the amplitude of sEPSCs or glutamate-activated currents, implicating a presynaptic mechanism of action. Echinacoside also potently blocked sustained repetitive firing, which is a basic mechanism of antiepileptic drugs. These results suggest that echinacoside exerts an antiepileptic effect on hippocampal CA3 pyramidal neurons by simultaneously decreasing glutamate release and blocking abnormal firing synchronization. Accordingly, our study provides experimental evidence that echinacoside may represent an effective pharmacological agent for treating epilepsy.

The Antiproliferation Activity of Ganoderma formosanum Extracts on Prostate Cancer Cells

( Cheng-yen Chiang ),( Kai-di Hsu ),( Yen-yi Lin ),( Chang-wei Hsieh ),( Jui-ming Liu ),( Tze-ying Lu ),( Kuan-chen Cheng ) 한국균학회 2020 Mycobiology Vol.48 No.3

Androgen-independent prostate cancer accounts for mortality in the world. In this study, various extracts of a medical fungus dubbed Ganoderma formosanum were screened for inhibition of DU145 cells, an androgen-independent prostate cancer cell line. Results demonstrated that both hexane (GF-EH) and butanol (GF-EB) fraction of G. formosanum ethanol extract inhibited DU145 cell viability in a dose-dependent manner. GF-EH induced cell-cycle arrest in G1 phase of DU145 cells via downregulation of cyclin E2 protein expression. In addition, GF-EB triggered extrinsic apoptosis of DU145 cells by activating caspase 3 gene expression resulting in programed cell death. Above all, both GF-EH and GF-EB show lower toxicity to normal human fibroblast cell line compared to DU145 cell, implying that they possess specific drug action on cancer cells. This study provides a molecular basis of G. formosanum extract as a potential ingredient for treatment of androgen-independent prostate cancer.

CONFIGURING PRINCIPAL OPPORTUNISM IN INTERNATIONAL JOINT VENTURE (IJV) PARENTS-IJV RELATIONSHIP: A COMBINATION OF SYMMETRICAL AND ASYMMETRICAL ANALYSIS TO ADVANCE AGENCY THEORY AND RESOURCE DEPENDENCE THEORY TRACK: PRODUCT INNOVATION AND DIFFUSION IN EMERGING MARKETS

Lu-Yun (Vivian) Cheng,Huifen (Helen) Cai,Zhongqi Jin 글로벌지식마케팅경영학회 2016 Global Marketing Conference Vol.2016 No.7

The paper addresses the phenomenon of the opportunism that arises from a parent (principal) toward an IJV (agent) and its antecedents. This study integrates Agency Theory and Resource Dependence Theory (RDT) to discover its determinants from the perspectives of principal opportunism. Using Structural Equation Modelling (SEM) techniques and fuzzy-set qualitative comparative analysis (fsQCA) based on a sample of 185 Chinese-foreign IJVs in China, which are useful to reals the overall story of the principal opportunism. This study finds an IJV depends on parents’ support in both knowledge- and property-based resources has more chances to subject to principal opportunism. The result also indicates that psychic distance has a negative impact on principal opportunism. fsQCA, however, provides further solutions that the specific combinations of these predictors or their negation predicts principle opportunism.

Inhibition of L-type Ca²⁺ current by ginsenoside Rd in rat ventricular myocytes

Lu, Cheng,Sun, Zhijun,Wang, Line The Korean Society of Ginseng 2015 Journal of Ginseng Research Vol.39 No.2

Background: Ginsenoside Rd (GSRd), one of the most abundant ingredients of Panax ginseng, protects the heart via multiple mechanisms including the inhibition of $Ca^{2+}$ influx.We intended to explore the effects of GSRd on L-type $Ca^{2+}$ current ($I_{Ca,L}$) and define the mechanism of the suppression of $I_{Ca,L}$ by GSRd. Methods: Perforated-patch recording and whole-cell voltage clamp techniques were applied in isolated rat ventricular myocytes. Results: (1) GSRd reduced $I_{Ca,L}$ peak amplitude in a concentration-dependent manner [half-maximal inhibitory concentration $(IC_{50})=32.4{\pm}7.1{\mu}mol/L$] and up-shifted the current-voltage (I-V) curve. (2) GSRd ($30{\mu}mol/L$) significantly changed the steady-state activation curve of $I_{Ca,L}$ ($V_{0.5}:-19.12{\pm}0.68$ vs. $-6.26{\pm}0.38mV$; n = 5, p < 0.05) and slowed down the recovery of $I_{Ca,L}$ from inactivation [the time content (${\zeta}$) from 91 ms to 136 ms, n = 5, p < 0.01]. (3) A more significant inhibitive effect of GSRd ($100{\mu}mol/L$) was identified in perforated-patch recording when compared with whole-cell recording [$65.7{\pm}3.2%$ (n = 10) vs. $31.4{\pm}5.2%$ (n = 5), p < 0.01]. (4) Pertussis toxin ($G_i$ protein inhibitor) completely abolished the $I_{Ca,L}$ inhibition induced by GSRd. There was a significant difference in inhibition potency between the two cyclic adenosine monophosphate elevating agents (isoprenaline and forskolin) prestimulation [$55{\pm}7.8%$ (n = 5) vs. $17.2{\pm}3.5%$ (n = 5), p < 0.01]. (5) 1H-[1,2,4]Oxadiazolo[4,3-a]-quinoxalin-1-one (a guanylate cyclase inhibitor) and N-acetyl-$\small{L}$-cysteine (a nitric oxide scavenger) partly recovered the $I_{Ca,L}$ inhibition induced by GSRd. (6) Phorbol-12-myristate-13-acetate (a protein kinase C activator) and GF109203X (a protein kinase C inhibitor) did not contribute to the inhibition of GSRd. Conclusion: These findings suggest that GSRd could inhibit $I_{Ca,L}$ through pertussis toxin-sensitive G protein ($G_i$) and a nitric oxide-cyclic guanosine monophosphate-dependent mechanism.