Lan Zhou University

Lanzhou, China

Lan Zhou University

Lanzhou, China
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Pan J.,Peking University | Sun K.,Peking University | Sun K.,Lan Zhou University | Liang Y.,Peking University | And 8 more authors.
Journal of Endodontics | Year: 2013

Introduction: Complete sterilization of an infected root canal is an important challenge in endodontic treatment. Traditional methods often cannot achieve high-efficiency sterilization because of the complexity of the root canal system. The objective of the study was to investigate in vitro the feasibility of using a cold plasma treatment of a root canal infected with Enterococcus faecalis biofilms. Methods: Seventy single-root teeth infected with E. faecalis biofilms were divided into 7 groups. Group 1 served as the negative control group (no treatment), and group 7 was the positive control group with teeth treated with calcium hydroxide intracanal medication for 7 days. Groups 2 to 6 included teeth treated by cold plasma for 2, 4, 6, 8, and 10 minutes, respectively. The disinfection of the E. faecalis biofilm was evaluated by colony-forming unit (CFU) counting. Scanning electron microscopy was used to evaluate the structural changes of the E. faecalis biofilm before and after plasma treatment. Confocal scanning laser microscopy was used to investigate the vitality of the microorganisms in the biofilm before and after plasma treatment. Results: A significant decrease in the number of CFUs was observed after prolonged cold plasma treatment (based on the statistical analysis of the teeth in groups 2-6). Compared with the positive control group, cold plasma treatment of 8 or 10 minutes (groups 5 and 6) had a significantly higher antimicrobial efficacy (P <.05). The scanning electron microscopic analysis showed that the bacteria membrane was ruptured, and the structure of the biofilm was fully destroyed by the plasma. Confocal scanning laser microscopic studies indicated that the plasma treatment induced E. faecalis death and destruction of the biofilm. Conclusions: The cold plasma had a high efficiency in disinfecting the E. faecalis biofilms in in vitro dental root canal treatment. © 2013 American Association of Endodontists.

Wang S.,Lan Zhou University | Dong X.,Xinjiang Institute of Water Conservancy | Wu R.,Xinjiang University
IAHS-AISH Publication | Year: 2011

A three-dimensional finite-difference groundwater flow and salt transport model was implemented to investigate a variety of hydrogeological conditions and to simulate the behaviour of the flow system and salt transport under different scenarios in the Yanqi basin and to estimate the amount of pumped groundwater needed to evaluate the impact of different scenarios of varying extraction on the fluctuations of water levels. The models provide insight into the status and evolution of the groundwater and salt. The results of the study are useful to predict the sustainability of the groundwater resources in the Yanqi basin and to evaluate possible management actions. Copyright © 2011 IAHS Press.

Xu F.,Lan Zhou University
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013

A continuous time model is proposed in this paper, dealing with the decentralized decision-making of multi-products promotion, under the condition of moral hazard. The main result is that when the revenue function and the movement law satisfy certain conditions, the optimal efforts level of the division in continuous time is the same with that in the static case, even though both are distorted compared with the optimal efforts level under complete information. © 2013 SPIE.

Yang L.,Lan Zhou University | Xue B.,Lan Zhou University | Nie M.,Lan Zhou University | Liu C.,Lan Zhou University | Zhang Q.,Lan Zhou University
Proceedings - 6th International Symposium on Computational Intelligence and Design, ISCID 2013 | Year: 2013

In this paper, a novel semi-blind channel estimate method is proposed for a multi-input multi-output orthogonal frequency division multiplexing (MIMO-OFDM) system with time-varying frequency selective fading channels. The channel estimation approach presented is based on ELM (extreme learning machine) which does not experience training bottleneck imposed by gradient descent-based approaches. Simulation results show that the ELM outperform other gradient descent-based feed forward neural networks by using the proposed estimation method in terms of Bit error rate(BER), mean square error (MSE) performances and estimating speed. © 2013 IEEE.

Xu L.,State University of New York at Buffalo | Tian Y.,Lan Zhou University | Jin X.,State University of New York at Buffalo | Chen J.,Tianjin Vocational Institute | And 3 more authors.
Proceedings - International Symposium on Biomedical Imaging | Year: 2012

A novel and efficient method to simulate the behavior of guidewires in the vascular system is proposed in this paper. The graph-theoretical method is based on the principle of minimal total potential energy. We formulate the total potential energy in the vascular interventional system as the summation of the elastic energy of the guidewire and the energy due to the deformation of the vessel wall. A graph is constructed with low complexity ensuring the efficiency of the single source shortest path. Compared to previous results, experiments in three phantoms have been conducted to evaluate the performance of the proposed method and the results demonstrate that our method can achieve 20% improvement with faster running time. © 2012 IEEE.

Li X.,Lan Zhou University | Wang S.,Lan Zhou University | Shang K.-Z.,Lan Zhou University | Li S.,Meteorological Observatory of Qinghai | And 3 more authors.
Applied Mechanics and Materials | Year: 2011

By using .NET platform and open source Sharpmap technology, a short-range and nowcasting operation system was established for Qinghai. Many kinds of data were integrated in this system, which get from air sounding, satellite, T213 numerical predicting products, doppler radar, lightning position system and automatic weather stations. The system with the functions of ensemble prediction and data retrieval and display, can meet the demand of short-range and nowcasting weather forecast, enhance efficiency of forecaster and provide a support for disaster prevention and mitigation in Qinghai. © (2011) Trans Tech Publications, Switzerland.

Che J.,Lan zhou University | Wang J.,Lan zhou University
Energy Conversion and Management | Year: 2010

In this paper, we present the use of different mathematical models to forecast electricity price under deregulated power. A successful prediction tool of electricity price can help both power producers and consumers plan their bidding strategies. Inspired by that the support vector regression (SVR) model, with the -insensitive loss function, admits of the residual within the boundary values of -tube, we propose a hybrid model that combines both SVR and Auto-regressive integrated moving average (ARIMA) models to take advantage of the unique strength of SVR and ARIMA models in nonlinear and linear modeling, which is called SVRARIMA. A nonlinear analysis of the time-series indicates the convenience of nonlinear modeling, the SVR is applied to capture the nonlinear patterns. ARIMA models have been successfully applied in solving the residuals regression estimation problems. The experimental results demonstrate that the model proposed outperforms the existing neural-network approaches, the traditional ARIMA models and other hybrid models based on the root mean square error and mean absolute percentage error. © 2010 Elsevier Ltd. All rights reserved.

Majoe D.,ETH Zurich | Gutknecht J.,ETH Zurich | Peng H.,Lan Zhou University
HEALTHINF 2012 - Proceedings of the International Conference on Health Informatics | Year: 2012

The EEG recording of a person has been considered as one potential component within an overall wearable sensor system that predicts the onset of mental health problems. Such a smart EEG sensor should provide detailed sensory information, be easy to use, and to put on and take off and whilst being very ergonomic the design should aim at a very low final end user cost to ensure the widest possible take up by the e-Health community. The work reported here describes the design of such a sensor, the performance and its use during extensive clinical trials aimed to establish the rules that link physiology sensing to mental health prediction.

Peng J.,Chang'an University | Fan Z.,Chang'an University | Wu D.,Chang'an University | Zhuang J.,Chang'an University | And 3 more authors.
Engineering Geology | Year: 2014

Continuous and heavy precipitation triggered a large loess landslide at the southern Dagou Village of Mapaoquan Town, Tianshui City, Gansu Province of China on July 21, 2013. The landslide debris rapidly turned into a debris flow that was deposited in the ravine mouth with the volume of 1.9×105 m3. Detailed field mapping, three-dimensional laser scanning, aerial photograph interpretation, and laboratory tests were carried out to study the formation and moving characteristics of the landslide and subsequent debris flow. The results showed that: 1) The peak flow velocity and peak discharge of the debris flow were estimated to be approximately 7.2m/s and 730m3/s, respectively. The velocity had a tendency to first increase and then decrease from the head to entrance in the Dagou gully. 2) The analysis of rainfall conditions showed that the effective antecedent rainfall within 7days and hourly rainfall intensity which triggered the slide-debris flows was 239mm and 20mm/h, respectively. Compared with the critical rainfall in this area, the effective antecedent rainfall was found to be more significant in triggering this event. 3) The mean and effective particle sizes were approximately 0.73-1.3mm and 0.036-0.087mm, respectively, and had the same distribution along the gully as the velocity, which confirmed the process of the variation in the flow velocity. 4) The scale amplification was very obvious in the formation and moving process of the slide-debris flows. © 2014.

Ma H.,Hubei University | Zhang M.,Hubei University | Zhang D.,Hubei University | Huang R.,Hubei University | And 9 more authors.
Chemistry - An Asian Journal | Year: 2010

G-quadruplex DNA plays an important role in the potential therapeutic target for the design and development of anticancer drugs. As various G-quadruplex sequences in the promoter regions or telomeres can form different secondary structural modes and display a diversity of biology functions, variant G-quadruplex interactive agents may be necessary to cure different disease by differentiating variant types of G-quadruplexes. We synthesize five cationic methylpyridylium corroles and compare the interactions of corroles with different types of G-quadruplexes such as cmyc, htelo, and bcl2 by using surface plasmon resonance. Because of the importance of human telomere G-quadruplex DNA, we focus on the biological properties of the interactions between human telo-mere G-quadruplex DNA and corrole isomers using CD, T m,PCR-stop (PCR = polymerase chain reaction), and polymerase-stop assay, which demonstrate the excellent ability of the corrole to induce and stabilize the Gquadruplex. This study provides the first experimental insight into how selectivity might be achieved for different G-quadruplexes by a single group of methylpyridylium corrole isomers that may be optimized for potential selective cancer therapy.

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