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Global Histone H4 Acetylation of IGF1 and GH Genes in Lungs of Somatic Cell Cloned Calves

  • Zhang, L.;Wang, S.H.;Fan, B.L.;Dai, Y.P.;Fei, J.;Li, N.
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.8
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    • pp.1090-1094
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    • 2006
  • Histone acetylation modification is one key mechanism in the regulation of gene activation. In this study, we investigated the global levels of histone H4 acetylation of insulin like growth factor I (IGF1) and growth hormone (GH) genes in the lungs of two somatic cell cloned calves. Data showed the levels of histone H4 acetylation of IGF1 and GH genes vary widely within different gene regions, and, in almost all regions of the two genes, acetylation levels are lower in the aberrant clone than in the normal clone. Thus we suggest that inefficient epigenetic reprogramming in the clone may affect the balance between acetylation and deacetylation, which will affect normal growth and development. These findings will also have implications for improvement of cloning success rates.

Hypothesis on the Role of Cytoplasmic "Short Base Sequences" in Carcinogenesis

  • Zhang, Jing-Yao;Xie, Lin;Tai, Ming-Hui;Wu, Qi-Fei;Liu, Chang
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.2
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    • pp.1155-1157
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    • 2013
  • Cancer is a highly complex medical problem with ramifications for public health throughout the world. Most studies have mainly focused on change in the nuclei as being aetiologically responsible. Few have examined the relationship between the cytoplasm and cancer, despite the fact that research has indicated that the cytoplasmic environment is an important factor for cellular differentiation and that the genetic information provided by the nucleus is entirely dependent on this environment for its expression. Gene mutations may be the result, rather than the cause of carcinogenesis. We submit a new concept - "short base sequences" (50-500 bps, including DNA or RNA sequences) in the cytoplasm which could play an important role in carcinogenesis. This is a new theory to explain the origin of the cancer.

Stimulation of Osteogenic Differentiation in Stromal Cells of Giant Cell Tumour of Bone by Zoledronic Acid

  • Yang, Tao;Zheng, Xiao-Fei;Li, Mei;Lin, Xi;Yin, Qing-Shui
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.9
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    • pp.5379-5383
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    • 2013
  • Therapeutic effects of zoledronic acid (ZOL) on giant cell tumour of bone (GCT) have been proven. Apoptosis induction was considered to be one of the mechanisms of ZOL tumour inhibition. In this study, we presented the possibility of an osteogenic differentiation stimulation mechanism of ZOL and further investigated dosage and time effects. We treated stromal cells of GCT (GCTSC) with ZOL for 48 hours at different concentrations ($0{\mu}M$, $0.01{\mu}M$, $0.1{\mu}M$, $1{\mu}M$, 5${\mu}M$, $30{\mu}M$) and assessed apoptotic and osteogenic differentiation markers with immunohistochemical techniques and real-time quantitative RT-PCR. Our results suggested that ZOL enhanced mRNA expression of Cbfa-1, osterix and osteocalcin genes with a maximum effect at $1{\mu}M$ in GCTSC. Time course experiments indicated a time dependent osteogenic differentiation effect. In conclusion, ZOL may be considered as an adjuvant in the treatment of GCT not only by inducing apoptosis but also by stimulating osteogenic differentiation of remaining tumor stromal cells after surgery.

A DTC Stator Flux Algorithm for the Performance Improvement of Induction Traction Motors

  • Van-Tien, Pham;Zheng, Trillion Q.;Yang, Zhong-ping;Lin, Fei;Do, Viet-dung
    • Journal of Power Electronics
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    • v.16 no.2
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    • pp.572-583
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    • 2016
  • In view of the speed control characteristics of induction traction motors and the problems of direct torque control (DTC) algorithms in current applications, this paper presents a DTC algorithm characterized by a symmetrical polygon flux control and a closed loop power control in the constant-torque base speed region and constant-power field-weakening region of induction traction motors. This algorithm only needs to add a stator flux control algorithm to the traditional DTC structures. This has the benefit of simplicity, while maintaining the features of traditional algorithms such as a rapid dynamic response, uncomplicated control circuit, reduced dependence on motor parameters, etc. In addition, it obtains a smoother flux trajectory that is conducive to improvement of the harmonic elimination capability, the switching frequency utilization as well as the torque and power performance in the field-weakening region. The effectiveness and feasibility of this DTC algorithm are demonstrated by both theoretical analysis and experimental results.

An Improved Central 60° Synchronous Modulation for High Transient Performance with PMSM Stator Flux Control Used in Urban Rail Transit Systems

  • Fang, Xiaochun;Lin, Fei;Yang, Zhongping
    • Journal of Power Electronics
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    • v.16 no.2
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    • pp.542-552
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    • 2016
  • Central 60° synchronous modulation is an easy pulse-width modulation (PWM) method to implement for the traction inverters of urban rail trains at a very low switching frequency. Unfortunately, its switching patterns are determined by a Fourier analysis of assumed steady-state voltages. As a result, its transient responses are not very good with over-currents and high instantaneous torque pulses. In the proposed solution, the switching patterns of the conventional central 60° modulation are modified according to the dynamic error between the target and actual stator flux. Then, the specific trajectory of the stator flux and current vector can be guaranteed, which leads to better system transients. In addition, stator flux control is introduced to get smooth mode switching between the central 60° modulation and the other PWMs in this paper. A detailed flow chart of the control signal transmission is given. The target flux is obtained by an integral of the target voltage. The actual PMSM flux is estimated by a minimum order flux state observer based on the extended flux model. Based on a two-level inverter model, improved rules in the α-β stationary coordinate system and equations of the switching patterns amendment are proposed. The proposed method is verified by simulation and experimental results.

A Novel High Step-Up Converter with a Switched-Coupled-Inductor-Capacitor Structure for Sustainable Energy Systems

  • Liu, Hongchen;Ai, Jian;Li, Fei
    • Journal of Power Electronics
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    • v.16 no.2
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    • pp.436-446
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    • 2016
  • A novel step-up DC-DC converter with a switched-coupled-inductor-capacitor (SCIC) which successfully integrates three-winding coupled inductors and switched-capacitor techniques is proposed in this paper. The primary side of the coupled inductors for the SCIC is charged by the input source, and the capacitors are charged in parallel and discharged in series by the secondary windings of the coupled inductor to achieve a high step-up voltage gain with an appropriate duty ratio. In addition, the passive lossless clamped circuits recycle the leakage energy and reduce the voltage stress on the main switch effectively, and the reverse-recovery problem of the diodes is alleviated by the leakage inductor. Thus, the efficiency can be improved. The operating principle and steady-state analyses of the converter are discussed in detail. Finally, a prototype circuit at a 50 kHz switching frequency with a 20-V input voltage, a 200-V output voltage, and a 200-W output power is built in the laboratory to verify the performance of the proposed converter.

Improved Deadbeat Current Controller with a Repetitive-Control-Based Observer for PWM Rectifiers

  • Gao, Jilei;Zheng, Trillion Q.;Lin, Fei
    • Journal of Power Electronics
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    • v.11 no.1
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    • pp.64-73
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    • 2011
  • The stability of PWM rectifiers with a deadbeat current controller is seriously influenced by computation time delays and low-pass filters inserted into the current-sampling circuit. Predictive current control is often adopted to solve this problem. However, grid current predictive precision is affected by many factors such as grid voltage estimated errors, plant model mismatches, dead time and so on. In addition, the predictive current error aggravates the grid current distortion. To improve the grid current predictive precision, an improved deadbeat current controller with a repetitive-control-based observer to predict the grid current is proposed in this paper. The design principle of the proposed observer is given and its stability is discussed. The predictive performance of the observer is also analyzed in the frequency domain. It is shown that the grid predictive error can be decreased with the proposed method in the related bode diagrams. Experimental results show that the proposed method can minimize the current predictive error, improve the current loop robustness and reduce the grid current THD of PWM rectifiers.

Treatment Planning in Smart Medical: A Sustainable Strategy

  • Hao, Fei;Park, Doo-Soon;Woo, Sang Yeon;Min, Se Dong;Park, Sewon
    • Journal of Information Processing Systems
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    • v.12 no.4
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    • pp.711-723
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    • 2016
  • With the rapid development of both ubiquitous computing and the mobile internet, big data technology is gradually penetrating into various applications, such as smart traffic, smart city, and smart medical. In particular, smart medical, which is one core part of a smart city, is changing the medical structure. Specifically, it is improving treatment planning for various diseases. Since multiple treatment plans generated from smart medical have their own unique treatment costs, pollution effects, side-effects for patients, and so on, determining a sustainable strategy for treatment planning is becoming very critical in smart medical. From the sustainable point of view, this paper first presents a three-dimensional evaluation model for representing the raw medical data and then proposes a sustainable strategy for treatment planning based on the representation model. Finally, a case study on treatment planning for the group of "computer autism" patients is then presented for demonstrating the feasibility and usability of the proposed strategy.

A Multi-Level Integrator with Programming Based Boosting for Person Authentication Using Different Biometrics

  • Kundu, Sumana;Sarker, Goutam
    • Journal of Information Processing Systems
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    • v.14 no.5
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    • pp.1114-1135
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    • 2018
  • A multiple classification system based on a new boosting technique has been approached utilizing different biometric traits, that is, color face, iris and eye along with fingerprints of right and left hands, handwriting, palm-print, gait (silhouettes) and wrist-vein for person authentication. The images of different biometric traits were taken from different standard databases such as FEI, UTIRIS, CASIA, IAM and CIE. This system is comprised of three different super-classifiers to individually perform person identification. The individual classifiers corresponding to each super-classifier in their turn identify different biometric features and their conclusions are integrated together in their respective super-classifiers. The decisions from individual super-classifiers are integrated together through a mega-super-classifier to perform the final conclusion using programming based boosting. The mega-super-classifier system using different super-classifiers in a compact form is more reliable than single classifier or even single super-classifier system. The system has been evaluated with accuracy, precision, recall and F-score metrics through holdout method and confusion matrix for each of the single classifiers, super-classifiers and finally the mega-super-classifier. The different performance evaluations are appreciable. Also the learning and the recognition time is fairly reasonable. Thereby making the system is efficient and effective.

Analyzing Chinese Online P2P Financial Product Purchase Decisions Utilizing the Framing Effect

  • Shang, Yu Fei;Kim, Soon-Hong
    • Journal of Distribution Science
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    • v.13 no.10
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    • pp.51-56
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    • 2015
  • Purpose - This study examines Chinese P2P investment decision processes from a behavioral economics approach. Research design, data, and methodology - We analyze the online P2P investment product purchase decisions of 241 respondents in China, March 2015 to May 2015. T-tests were conducted to determine whether the framing effect influenced investor investment preferences. The Association Rule was used to identify the framing effect of respondent demographic characteristics on joint decisions regarding stable or risky investment products. Results - There are significant differences between the two groups (positive framing and negative framing) and their product-choosing behavior. In the positive framing group, female investors, young investors, investors with non-financial occupations and with limited or no experience, preferred stable P2P investment products. In contrast, in the negative framing group, investors with extensive investment experience preferred risky investment products. Conclusions - The framing effect influences investor choices in online P2P investment products. It is necessary to implement comprehensive supervision and full information disclosure regarding P2P investment products. P2P investment websites can also adopt different marketing strategies according to investor gender and age.