oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 33 )

2018 ( 648 )

2017 ( 652 )

2016 ( 605 )

Custom range...

Search Results: 1 - 10 of 41164 matches for " Nan Xiao "
All listed articles are free for downloading (OA Articles)
Page 1 /41164
Display every page Item
Chemical composition, antioxidant and antibacterial activities of essential oil from Korean Citrus unshiu peel  [PDF]
Xiao Nan Yang, Sun Chul Kang
Journal of Agricultural Chemistry and Environment (JACEN) , 2013, DOI: 10.4236/jacen.2013.23007
Abstract: The chemical composition, antioxidant and antibacterial activities of essential oil from peel of Citrus unshiuwhich cultivated in South Korea were investigated. Eight compounds were identified as l-limonene (88.11%), γ-terpinene (4.66%), cyclohexane, 2,4-diisopropenyl-1-methyl-1-vinyl (1.82%), diethyl phthalate (1.02%), β-linalool (0.97%), β-myrcene (0.91%), α-farnesene (0.91%) and o-cymene (0.85%)
by GC-MS. The SC50values of this essential oil on DPPH and superoxide anion were 0.21 and 0.22% (v/v), respectively. The results of zone of inhibition, MIC, MBC and cell viability demonstrated the essential oil of-Citrus unshiupeel displayed antibacterial effect against B. cereus KCTC 14042, B. subtilis ATCC 6633 and S. aureusATCC 6538. The release of cell material and potassium ion from the B. subtilis ATCC 6633 cells treated with essential oil was further investigated. SEM observation also revealed the damaging effect of the essential oil on the morphology of B. subtilisATCC 6633 cells at minimum inhibitory concentration.


DETERMINATION OF MINIMAL MATRICES OF SIMPLE CYCLES IN LDPC CODES
Zhang Nan,Gao Xiao
International Journal of Wireless & Mobile Networks , 2011,
Abstract: Simple cycles are the easiest cycles to reveal in Low-Density Parity Check (LDPC) codes. All minimummatrices of simple cycles with the same length will be equivalent after row or column permutations .Inthis paper,we analysis the structure of simple cycles and show all figures of minimal matrices of simplecycles. Firstly, we introduce a more general definition of cycle and investigate simple cycles in LDPCcodes. Secondly, we present the number of simple cycles of arbitrary length and all the minimal matricesof simple cycles.
Proposal for Observing Dynamic Jahn-Teller Effect of Single Solid-State Defects
Xing Xiao,Nan Zhao
Physics , 2015,
Abstract: Jahn-Teller effect (JTE) widely exists in polyatomic systems including organic molecules, nano-magnets, and solid-state defects. Detecting the JTE at single-molecule level can provide unique properties about the detected individual object. However, such measurements are challenging because of the weak signals associated with a single quantum object. Here, we propose that the dynamic JTE of single defects in solids can be observed with nearby quantum sensors. With numerical simulations, we demonstrate the real-time monitoring of quantum jumps between different stable configurations of single substitutional nitrogen defect centers (P1 centers) in diamond. This is achieved by measuring the spin coherence of a single nitrogen-vacancy (NV) center near the P1 center with the double electron-electron resonance (DEER) technique. Our work extends the ability of NV center as a quantum probe to sense the rich physics in various electron-vibrational coupled systems.
Preparation and properties of cast polyurethane elastomers with molecularly uniform hard segments based on 2,4-toluene diisocyanate and 3,5-dimethyl-thioltoluenediamine  [PDF]
Xiao-Dong Chen, Nan-Qiao Zhou, Hai Zhang
Journal of Biomedical Science and Engineering (JBiSE) , 2009, DOI: 10.4236/jbise.2009.24038
Abstract: A series of three cast polyurethane elastomers were prepared from 2,4-toluene diisocyanate (TDI) and 3,5-dimethyl-thioltoluenediamine (D MTDA) chain extender, with polyethylene adi-pate (PEA), polyoxytetramethylene glycol (PTMG) and polycaprolactone (PCL) soft seg-ments. The polyol molecular weights em-ployed was 2000g/mol. The polyurethane elastomers were characterized by an elec-tronmechanical universal testing machine, an Akron abrasion loss tester, a LX-A Shore du-rometer, a rebound resilience equipment and a Dynamic- Mechanical analyzer. In addition, fractured surface of the polyurethane elas-tomers was investigated by a field emission scanning electron microscopy (SEM). The test results showed the PCL based elastomer ex-hibits the excellent tear and stress-strain properties that polyester based elastomers offer, while retaining superior compression set and resilience similar to polyether based elas-tomers. The static and dynamic properties of the PCL based elastomer were more suitable for dynamic applications. The SEM micro-graphs of all polyurethane samples indicated the existing of the microphase separation structure. Particles of the dispersed phase formed by the hard phase and crystalline part of the soft phase grows bigger with the in-creasing crystallinity of the soft segments. The hard domains are irregular shapes and with the sizes of a few micrometers.
Analytical Solutions for Corrosion-Induced Cohesive Concrete Cracking
Hua-Peng Chen,Nan Xiao
Journal of Applied Mathematics , 2012, DOI: 10.1155/2012/769132
Abstract: The paper presents a new analytical model to study the evolution of radial cracking around a corroding steel reinforcement bar embedded in concrete. The concrete cover for the corroding rebar is modelled as a thick-walled cylinder subject to axisymmetrical displacement constraint at the internal boundary generated by expansive corrosion products. A bilinear softening curve reflecting realistic concrete property, together with the crack band theory for concrete fracture, is applied to model the residual tensile stress in the cracked concrete. A governing equation for directly solving the crack width in cover concrete is established for the proposed analytical model. Closed-form solutions for crack width are then obtained at various stages during the evolution of cracking in cover concrete. The propagation of crack front with corrosion progress is studied, and the time to cracking on concrete cover surface is predicted. Mechanical parameters of the model including residual tensile strength, reduced tensile stiffness, and radial pressure at the bond interface are investigated during the evolution of cover concrete cracking. Finally, the analytical predictions are examined by comparing with the published experimental data, and mechanical parameters are analysed with the progress of reinforcement corrosion and through the concrete cover.
A Local World Evolving Model for Energy-Constrained Wireless Sensor Networks
Nan Jiang,Huan Chen,Xiang Xiao
International Journal of Distributed Sensor Networks , 2012, DOI: 10.1155/2012/542389
Abstract: Energy efficiency is one of the basic requirements of wireless sensor networks (WSNs) yet this problem has not been sufficiently explored in the context of cluster-based sensor networks. Specifically, the interaction of different types of sensor nodes is one of the major factors of energy efficiency in large-scale heterogeneous networks. In this paper, we aim at improving the interactions among sensor nodes, and we present a heterogeneous local-world model to form large-scale wireless sensor networks based on complex network theory. Two types of nodes, normal nodes and cluster nodes, are added to the networks. The degree distribution for this model is obtained analytically by mean-field theory. This approach depicts the evolution of the network as having a topological feature that is not completely exponential and not completely power law; instead, it behaves between them. The experiment and simulation indicate that the control method has excellent robustness and a satisfactory control effect (interaction of different types of sensor nodes). Furthermore, the results also show that the higher the generation rate of the cluster nodes is, the closer the degree distribution follows the power-law distribution.
Simulation of Multi-stage Flash(MSF)Desalination Process  [PDF]
Wu Lian-ying, Xiao Sheng-nan, Gao Cong-jie
Advances in Materials Physics and Chemistry (AMPC) , 2012, DOI: 10.4236/ampc.2012.24B052
Abstract: MSF seawater desalination has become an important technology to solve the scarce of fresh water resources in the world. But the high energy cost is the bottle-neck of extendibility and application. In this paper, the principle of MSF is analyzed and the single flash stage is divided into several elementary unit operations. The Aspen Plus is adopted to simulate MSF desalination process. The effect factor of MSF system, such as the feed seawater temperature, the top brine temperature(TBT) and the stage number, is investigated and the optimum operation condition is obtained.
A meta-analysis that compares the use of either peginterferon-α2a or peginterferon-α2b plus ribavirin for HCV infection
Nan Xiao, Shuang Shi, Hui Zhuang
Hepatic Medicine: Evidence and Research , 2010, DOI: http://dx.doi.org/10.2147/HMER.S11916
Abstract: meta-analysis that compares the use of either peginterferon-α2a or peginterferon-α2b plus ribavirin for HCV infection Original Research (3267) Total Article Views Authors: Nan Xiao, Shuang Shi, Hui Zhuang Published Date July 2010 Volume 2010:2 Pages 99 - 109 DOI: http://dx.doi.org/10.2147/HMER.S11916 Nan Xiao*, Shuang Shi*, Hui Zhuang Department of Microbiology, Peking University Health Science Center, Beijing, China, *These authors contributed equally to this work Background: Two kinds of peginterferons, peginterferon-α2a (PEG-IFN-α2a) and peginterferon-α2b (PEG-IFN-α2b), are used in the treatment of chronic hepatitis C virus (HCV) infection. However, it is unclear which is better in terms of virological responses and patient compliance. We conducted a meta-analysis to assess which peginterferon was better when used with ribavirin. Methods: Relevant clinical trials were identified through the PubMed and EMBASE databases. Primary outcomes included early virological response (EVR), end of treatment response (ETR) and sustained virological response (SVR). Secondary outcomes included biochemical and histological responses and the discontinuation of treatment after adverse events. Meta-analysis was performed using xed-effect or random-effect methods, depending on absence or presence of signi cant heterogeneity. Analyses were performed with Review Manager Version 4.2.2. Results: Seven clinical trials were included that involved 3,526 patients in total; six were randomized clinical trials (RCTs) and one was nonrandomized. PEG-IFN-α2a plus ribavirin was better than PEG-IFN-α2b plus ribavirin with regards to ETR (relative risk [RR] = 1.21, 95% confidence interval [CI]: 1.14–1.28). This advantage was less obvious for EVR (RR = 1.12, 95% CI: 1.06–1.19) and SVR (RR = 1.10, 95% CI: 1.02–1.18). Patients who received PEG-IFN-α2a were less likely to discontinue treatment for safety reasons (RR = 0.85, 95% CI: 0.52–1.38). Conclusion: We demonstrated that PEG-IFN-α2a was a better choice than PEG-IFN-α2b in terms of virological responses.
Non-preventive use of antibiotics in patients with severe acute pancreatitis treated with integrated traditional Chinese and Western medicine therapy: a randomized controlled trial
Xiao-nan YANG,Qing XIA
Zhong Xi Yi Jie He Xue Bao , 2009,
Abstract: Objective: To investigate the prognostic effects of integrated traditional Chinese and Western medicine therapy without antibiotics in treatment of patients with severe acute pancreatitis (SAP).Methods: SAP patients were randomly divided into treatment group (26 cases included) and control group (28 cases included). In addition to the same protocol of integrated traditional Chinese and Western medicine treatment for both groups, intravenous drip infusion of 0.5 g imipenem-cilastatin was administered to the patients in the control group every eight hours for ten days. The 48-hour Ranson score, 24-hour acute physiology and chronic heath evaluation Ⅱ score, and incidence rates of complications were observed. The concentrations of serum C-reactive protein (CRP) on days 1, 3, 7 and 10 were measured, and strains of infection were detected with smear and culture examination for bacteria and fungi.Results: There were no statistical differences in demographic information, baseline data and incidence rates of complications between the two groups (P>0.05), but fungal infection rate in the control group was higher than that in the treatment group (P<0.05). There were no statistical differences in infection rates of G- and G+ germs between the two groups; blood and some organs including lung, pancreas, intestine, and urethra were infected with bacteria and fungi. There were also no significant differences in the serum CRP concentrations on days 1, 3, 7 and 10 between the two groups (P>0.05), but the serum CRP concentrations on days 1, 3, 7 and 10 in infected patients were higher than those in non-infected patients (P<0.05, P<0.01).Conclusion: The study cannot confirm that the incidence rates of secondary infection and mortality in SAP patients treated with integrated traditional Chinese and Western medicine are reduced by prophylaxis with imipenem-cilastatin.
A Self-Referencing Detection of Microorganisms Using Surface Enhanced Raman Scattering Nanoprobes in a Test-in-a-Tube Platform
Nan Xiao,Chao Wang,Chenxu Yu
Biosensors , 2013, DOI: 10.3390/bios3030312
Abstract: Anisotropic nanoparticles ( i.e., silver nanocubes) were functionalized with target-specific antibodies and Raman active tags to serve as nanoprobes for the rapid detection of bacteria in a test-in-a-tube platform. A self-referencing scheme was developed and implemented in which surface enhanced Raman spectroscopic (SERS) signatures of the targets were observed superimposed with the SERS signals of the Raman tags. The assessment through the dual signals (superimposed target and tag Raman signatures) supported a specific recognition of the targets in a single step with no washing/separation needed to a sensitivity of 10 2 CFU/mL, even in the presence of non-target bacteria at a 10 times higher concentration. The self-referencing protocol implemented with a portable Raman spectrometer potentially can become an easy-to-use, field-deployable spectroscopic sensor for onsite detection of pathogenic microorganisms.
Page 1 /41164
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.