Chung Yuan Christian University

About: Chung Yuan Christian University is a education organization based out in Taoyuan City, Taiwan. It is known for research contribution in the topics: Membrane & Fuzzy logic. The organization has 9819 authors who have published 11623 publications receiving 213139 citations. The organization is also known as: Tiong-gôan-tāi-ha̍k & CYCU.

Strong decays of charmed baryons in heavy hadron chiral perturbation theory

Abstract: Strong decays of charmed baryons are analyzed in the framework of heavy hadron chiral perturbation theory (HHChPT) in which heavy quark symmetry and chiral symmetry are synthesized. HHChPT works excellently for describing the strong decays of s-wave charmed baryons. For L=1 orbitally excited states, two of the unknown couplings, namely, $h_2$ and $h_{10}$, are determined from the resonant $\Lambda_c^+\pi\pi$ mode produced in the $\Lambda_c(2593)$ decay and the width of $\Sigma_c(2800)$, respectively. Predictions for the strong decays of the p-wave charmed baryon states $\Lambda_c(2625)$, $\Xi_c(2790)$ and $\Xi_c(2815)$ are presented. Since the decay $\Lambda_c(2593)^+\to\Lambda_c^+\pi\pi$ receives non-resonant contributions, our value for $h_2$ is smaller than the previous estimates. We also discuss the first positive-parity excited charmed baryons. We conjecture that the charmed baryon $\Lambda_c(2880)$ with $J^P=\frac52^+$ is an admixture of $\Lambda_{c2}(\frac52^+)$ with and $\tilde\Lambda''_{c3}(\frac52^+)$: both are L=2 orbitally excited states. The potential model suggests $J^P=\frac52^-$ or $\frac32^+$ for $\Lambda_c(2940)^+$. Measurements of the ratio of $\Sigma_c^*\pi/\Sigma_c\pi$ will enable us to discriminate the $J^P$ assignments for $\Lambda_c(2940)$. We advocate that the $J^P$ quantum numbers of $\Xi_c(2980)$ and $\Xi_c(3077)$ are $\frac12^+$ and $\frac52^+$, respectively. Under this $J^P$ assignment, it is ready to understand why $\Xi_c(2980)$ is broader than $\Xi_c(3077)$.

Applications of fault diagnosis in rotating machinery by using time series analysis with neural network

Abstract: The common diagnosis method of time series analysis is an autoregressive (AR) method, which is a kind of math model that can be established by time difference and vibration amplitude. As the AR model utilized the math method for fitting the variable, the AR coefficients represent the signal features and can be used to determine fault types. This study proposed the difference values of AR coefficients, which indicated that the AR coefficients of ideal signal for normal machine are deducted from faulty machines. It is convention that the relationship between the difference values of AR coefficients and fault types as trained by using back-propagation neural network (BPNN). The new fault diagnosis method by using the difference of AR coefficients with BPNN was proposed in this study. The diagnosis results were obtained and compared with the three methods, which include the difference of AR coefficients with BPNN, the AR coefficients with BPNN and the distance of AR coefficients method for 23 samples. And the diagnosis results obtained by using the difference of AR coefficients with BPNN were superior to AR coefficients with BPNN and distance of AR coefficients methods.

Apoptotic signaling in methylglyoxal-treated human osteoblasts involves oxidative stress, c-Jun N-terminal kinase, caspase-3, and p21-activated kinase 2.

Abstract: Methylglyoxal (MG) is a reactive dicarbonyl compound endogenously produced mainly from glycolytic intermediates. MG is cytotoxic through induction of cell death, and elevated MG levels in diabetes patients are believed to contribute to diabetic complications. In this report, we show for the first time that MG treatment triggers apoptosis in human osteoblasts. We further show that MG-induced apoptosis of osteoblasts involves specific apoptotic biochemical changes, including oxidative stress, c-Jun N-terminal kinase (JNK) activation, mitochondrial membrane potential changes, cytochrome C release, increased Bax/Bcl-2 protein ratios, and activation of caspases (caspase-9, caspase-3) and p21-activated protein kinase 2 (PAK2). Treatment of osteoblasts with SP600125, a JNK-specific inhibitor, led to a reduction in MG-induced apoptosis and decreased activation of caspase-3 and PAK2, indicating that JNK activity is upstream of these events. Experiments using anti-sense oligonucleotides against PAK2 further showed that PAK2 activation is required for MG-induced apoptosis in osteoblasts. Interestingly, we also found that MG treatment triggered nuclear translocation of NF-kappaB, although the precise regulatory role of NF-kappaB activation in MG-induced apoptosis remains unclear. Lastly, we examined the effect of MG on osteoblasts in vivo, and found that exposure of rats to dietary water containing 100-200 microM MG caused bone mineral density (BMD) loss. Collectively, these results reveal for the first time that MG treatment triggers apoptosis in osteoblasts via specific apoptotic signaling, and causes BMD loss in vivo.