An Improved Method of Maximum Power Point Tracking Strategy for Wind Power Conversion System

CHEN Ran,CHEN Jie,CHEN Jia-wei,CHEN Zhi-hui,GONG Chun-ying,YAN Yang-guang 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

The turbine speed loop adjustment is the key link of the designing of the controller for the fixed pitch variable speed wind energy conversion systems (WECS). Because of the strong nonlinear, big inertia and mechanical damping characteristics, it’s difficult to designing the controller of the wind power systems. In this paper, a small signal model is present, and based on the analyzing; a wind turbine speed loop regulator is designed. Then, a method of tracking the peak power conversion system is proposed, which is independent of the turbine parameters and air density. At last, simulation system is built, and the results of the simulation experiments show that, the performance of the controller algorithm meet the requirements of the MPPT without wind measurement.

Combined Assessment of Serum Alpha-Synuclein and Rab35 is a Better Biomarker for Parkinson’s Disease

Hung-Li Wang,Chin-Song Lu,Tu-Hsueh Yeh,Yu-Ming Shen,Yi-Hsin Weng,Ying-Zu Huang,Rou-Shayn Chen,Yu-Chuan Liu,Yi-Chuan Cheng,Hsiu-Chen Chang,Ying-Ling Chen,Yu-Jie Chen,Yan-Wei Lin,Chia Chen Hsu,Huang-Li 대한신경과학회 2019 Journal of Clinical Neurology Vol.15 No.4

Background and Purpose It is essential to develop a reliable predictive serum biomarker for Parkinson’s disease (PD). Te accumulation of alpha-synuclein (αSyn) and up-regulated expression of Rab35 participate in the etiology of PD. Te purpose of this investigation was to determine whether the combined assessment of serum αSyn and Rab35 is a useful predictive biomarker for PD. Methods Serum levels of αSyn or Rab35 were determined in serum samples from 59 sporadic PD patients, 19 progressive supranuclear palsy (PSP) patients, 20 multiple system atrophy (MSA) patients, and 60 normal controls (NC). Receiver operating characteristics (ROC) curves were calculated to determine the diagnostic accuracy of αSyn or/and Rab35 in discriminating PD patients from NC or atypical parkinsonian patients. Results The levels of αSyn and Rab35 were increased in PD patients. The serum level of Rab35 was positively correlated with that of αSyn in PD patients. Compared to analyzing αSyn or Rab35 alone, the combined analysis of αSyn and Rab35 produced a larger area under the ROC curve and performed better in discriminating PD patients from NC, MSA patients, or PSP patients. When age was dichotomized at 55, 60, 65, or 70 years, the combined assessment of αSyn and Rab35 for classifying PD was better in the group below the cutof age than in the group above the cutof age. Conclusions Combined assessment of serum αSyn and Rab35 is a better biomarker for discriminating PD patients from NC or atypical parkinsonian patients, and is a useful predictive biomarker for younger sporadic PD patients.

Use of an Artificial Neural Network to Predict Risk Factors of Nosocomial Infection in Lung Cancer Patients

Chen, Jie,Pan, Qin-Shi,Hong, Wan-Dong,Pan, Jingye,Zhang, Wen-Hui,Xu, Gang,Wang, Yu-Min Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.13

Statistical methods to analyze and predict the related risk factors of nosocomial infection in lung cancer patients are various, but the results are inconsistent. A total of 609 patients with lung cancer were enrolled to allow factor comparison using Student's t-test or the Mann-Whitney test or the Chi-square test. Variables that were significantly related to the presence of nosocomial infection were selected as candidates for input into the final ANN model. The area under the receiver operating characteristic (ROC) curve (AUC) was used to evaluate the performance of the artificial neural network (ANN) model and logistic regression (LR) model. The prevalence of nosocomial infection from lung cancer in this entire study population was 20.1% (165/609), nosocomial infections occurring in sputum specimens (85.5%), followed by blood (6.73%), urine (6.0%) and pleural effusions (1.82%). It was shown that long term hospitalization (${\geq}22days$, P= 0.000), poor clinical stage (IIIb and IV stage, P=0.002), older age (${\geq}61days$ old, P=0.023), and use the hormones were linked to nosocomial infection and the ANN model consisted of these four factors. The artificial neural network model with variables consisting of age, clinical stage, time of hospitalization, and use of hormones should be useful for predicting nosocomial infection in lung cancer cases.

Power and Promise of Ubiquitin Carboxyl-terminal Hydrolase 37 as a Target of Cancer Therapy

Chen, Yan-Jie,Ma, Yu-Shui,Fang, Ying,Wang, Yi,Fu, Da,Shen, Xi-Zhong Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.4

Ubiquitin carboxyl-terminal hydrolase 37 (UCH37, also called UCHL5), a member of the deubiquitinating enzymes, can suppress protein degradation through disassembling polyubiquitin from the distal subunit of the chain. It has been proved that UCH37 can be activated by proteasome ubiqutin chain receptor Rpn13 and incorporation into the 19S complex. UCH37, which has been reported to assist in the mental development of mice, may play an important role in oncogenesis, tumor invasion and migration. Further studies will allow a better understanding of roles in cell physiology and pathology, embryonic development and tumor formation, hopefully providing support for the idea that UCH37 may constitute a new interesting target for the development of anticancer drugs.

Identification of protoberberine alkaloids as novel histone methyltransferase G9a inhibitors by structure-based virtual screening

Chen, Jie,Lin, Xiao,Park, Kyoung Jin,Lee, Kang Ro,Park, Hyun-Ju Springer-Verlag 2018 Journal of computer-aided molecular design Vol.32 No.9

Thermo-/pH-dual responsive properties of hyperbranched polyethylenimine grafted by phenylalanine

Jie Chen,Jialiang Xia,Huayu Tian,Zhaohui Tang,Chaoliang He,Xuesi Chen 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.1

Novel thermo- and pH-dual responsiveamphiphilic copolymers were synthesized based on hyperbranchedpolyethylenimine (PEI) by grafting L-phenylalanine. The phenylalanine-modified PEI exhibited lowercytotoxicity than commercial PEI. These copolymersshowed the phenomena of phase transitions in response topH and temperature. The dilute copolymer solution atlower pH displayed the higher LCST. Furthermore, LCSTincreased with the increasing of phenylalanine graftingdensity. LCST of these copolymers were tunable from 7.2to 59.6 C by the degree of amidation and pH of solution. DLS and TEM experiments certified that the copolymerchains aggregated to form small size particles as increasingthe temperature above LCST. For these reasons, theobtained smart copolymers were considered to be potentialgene/drug carriers in biomedical field.

A Secret Sharing Scheme Based on AES

Jie Cui,Lei Chen,Yiming Zhang,Zhiqiang Xie,Hong Zhong 보안공학연구지원센터 2014 International Journal of Security and Its Applicat Vol.8 No.6

In order to solve the key setting difficulty and the key security problem in the file encryption, key distributed storage technology may be a proper choice to help improve the safety of the key. In the paper, a novel secret sharing scheme is proposed by AES encryption algorithm for file confidentiality, dynamic key generation mechanism to generate keys, multi-secret-sharing ideas on key pre-treatment, using Shamir threshold scheme for secret dispersed storage. Finally, a few tests are carried out and the test results suggest that the efficiency of the whole scheme is good.

Imaging Cell Surface Glycans ofCardiomyocytes in Intact Rat Heart

Jie Rong,Jing Han,Lianshun Feng,Yanhong Tan,Qiwei Wang,Yingying Chen,Shiqiang Wang,Xing Chen 한국당과학회 2012 한국당과학회 학술대회 Vol.2012 No.1

Glycosylation is essential for proper cell signaling and embryonic development. Changes in glycosylation are often a hallmark of disease states. Cardiovascular disease has become one of the top causes of death. Many studies using rat models have related heart diseases and regulations of heart physiological functions to altered glycosylations. However, the dynamic regulation and molecular mechanism of glycosylation in heart are not clear. Rat is an important model organism for human cardiovascular disease studies. Isolated intact rat hearts are often used in physiological and pathological studies. In situ imaging biomolecules in intact heart avoid possible damage of myocyte and biased loss of cardiac myocytes during enzymatic isolation. Here, we applied the metabolic glycan labeling technique for imaging sialylation and O-linked glycosylation in living cardiomyocytes and intact rat hearts. The effects of unnatural sugars on the function of cardiomyocytes and hearts were evaluated. We found unnatural sugars did not perturb the function of cardiomyocytes and hearts. Glycan imaging revealed an interesting distribution pattern: sialic acid or O- linked glycan enriched at intercalated discs of adult rat cardiomyocytes. We also observed that the glycosylations of cardiomyocytes were altered in isoproterenol-induced cardiac hypertrophy rat models. This work extends the application of metabolic glycan labeling technique to probe glycosylations in rats and provides the first example of using this technique for in situ cellular glycans imaging in mammalian model organisms. The biological significance of altered glycosylations in cardiac hypertrophy heart is under investigation in our lab.

Computer-Aided Discovery of Massonianoside B as a Novel Selective DOT1L Inhibitor

Chen, Jie,Park, Hyun-Ju AMERICAN CHEMICAL SOCIETY 2019 ACS CHEMICAL BIOLOGY Vol.14 No.5

<P>Protein methyltransferases (PMTs) are involved in numerous biological processes and have been studied as a promising target class in the field of oncology and other diseases. Disruptor of telomeric silencing 1-like (DOT1L), a histone H3 lysine 79 (H3K79) methyltransferase, plays an important role in the progressions of mixed-lineage leukemia (MLL)-rearranged leukemias and has been validated as a potential therapeutic target. Here we report the discovery and characterization of a novel DOT1L inhibitor, massonianoside B (MA), by pharmacophore-based <I>in silico</I> screening and biological studies. MA is a structurally unique natural product inhibitor of DOT1L with an IC<SUB>50</SUB> value of 399 nM. The compound displays high selectivity for DOT1L over other <I>S</I>-adenosylmethionine (SAM)-dependent PMTs. Treatment of MLL-rearranged leukemia cells with MA gives a dose-dependent reduction in cellular levels of histone lysine 79 mono- and dimethylation without affecting the methylation of other histone sites. Moreover, MA selectively inhibits proliferation and causes apoptosis in MLL-rearranged leukemia cells and downregulates the expression of MLL fusion target genes, including <I>HOXA9</I> and <I>MEIS1</I>. Molecular docking analysis revealed that MA may bind to the SAM-binding site of DOT1L. We identified MA as not only a novel DOT1L inhibitor with antileukemic activity but also a DOT1L-targeted molecular probe that may serve as a useful chemical tool for investigating the role of DOT1L in biological processes.</P> [FIG OMISSION]</BR>

Recent Development on Photocatalysts and Membrane Processes for Photoreduction of CO2 into C1 Solar Fuels

Chen Jian Jie,Oh Pei Ching,Saleh Syafiqa Bt M. 한국화학공학회 2024 Korean Journal of Chemical Engineering Vol.41 No.3

This review paper delineates an overview of recent developments on photocatalytic processes for the photoreduction of CO 2 into C1 solar fuels including methanol and methane. The effi ciency of the novel processes reported is compared in terms of the yields of C1 fuels. Brief introduction on synthetic protocols of the cited photocatalysts employed for the photoreduction of CO 2 into C1 fuels is succinctly discoursed in this work. Furthermore, an additional review section is also included for summarizing the recently published ideas of diff erent confi gurations of photocatalytic membrane processes utilized for the separation of CO 2 converted C1 products from the reaction solvent. It was concluded that there is still substantial room of improvement for both newly developed photocatalytic systems and membrane processes in terms of C1 yield and the fuel separation effi ciency, respectively. Despite its potential as a promising green candidate used for carbon capture and utilization, additional studies are still necessary prior to its scalable application in industry. These studies should take a deep dive into the optimization of both photocatalytic and membrane separation processes, largely by development of novel photocatalytic systems that are highly effi cient in CO 2 conversion and membrane systems that are selective toward desired fuel products.