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Acidity of Solid and Liquid Acids Probed by P-31 NMR Chemical Shifts of Phosphine Oxides
Chih-Yi Yang,Chih-Chung Chang,Ningdong Feng,Shing-Jong Huang
Journal of Analytical Science & Technology , 2011,
Abstract: A novel method for acidity characterization of solid and liquid acids is proposed. Surpassing conventional methods, this technique employs 31P nuclear magnetic resonance (NMR) of adsorbed phosphine oxides is capable of monitoring a wide range of acidic strengths from weak to super acids with superior sensitivity.
Plasminogen activator inhibitor-1 4G/5G polymorphism and retinopathy risk in type 2 diabetes: a meta-analysis
Zhang Tengyue,Pang Chong,Li Ningdong,Zhou Elaine
BMC Medicine , 2013, DOI: 10.1186/1741-7015-11-1
Abstract: Background Mounting evidence has suggested that plasminogen activator inhibitor-1 (PAI-1) is a candidate for increased risk of diabetic retinopathy. Studies have reported that insertion/deletion polymorphism in the PAI-1 gene may influence the risk of this disease. To comprehensively address this issue, we performed a meta-analysis to evaluate the association of PAI-1 4G/5G polymorphism with diabetic retinopathy in type 2 diabetes. Methods Data were retrieved in a systematic manner and analyzed using Review Manager and STATA Statistical Software. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of associations. Results Nine studies with 1, 217 cases and 1, 459 controls were included. Allelic and genotypic comparisons between cases and controls were evaluated. Overall analysis suggests a marginal association of the 4G/5G polymorphism with diabetic retinopathy (for 4G versus 5G: OR 1.13, 95%CI 1.01 to 1.26; for 4G/4G versus 5G/5G: OR 1.30, 95%CI 1.04 to 1.64; for 4G/4G versus 5G/5G + 4G/5G: OR 1.26, 95%CI 1.05 to 1.52). In subgroup analysis by ethnicity, we found an association among the Caucasian population (for 4G versus 5G: OR 1.14, 95% CI 1.00 to 1.30; for 4G/4G versus 5G/5G: OR 1.33, 95%CI 1.02 to 1.74; for 4G/4G versus 5G/5G + 4G/5G: OR 1.41, 95%CI 1.13 to 1.77). When stratified by the average duration of diabetes, patients with diabetes histories longer than 10 years have an elevated susceptibility to diabetic retinopathy than those with shorter histories (for 4G/4G versus 5G/5G: OR 1.47, 95%CI 1.08 to 2.00). We also detected a higher risk in hospital-based studies (for 4G/4G versus 5G/5G+4G/5G: OR 1.27, 95%CI 1.02 to 1.57). Conclusions The present meta-analysis suggested that 4G/5G polymorphism in the PAI-1 gene potentially increased the risk of diabetic retinopathy in type 2 diabetes and showed a discrepancy in different ethnicities. A higher susceptibility in patients with longer duration of diabetes (more than 10 years) indicated a gene-environment interaction in determining the risk of diabetic retinopathy.
Association of OPA1 Polymorphisms with NTG and HTG: A Meta-Analysis
Yatu Guo, Xia Chen, Hongtuan Zhang, Ningdong Li, Xiong Yang, Wenbo Cheng, Kanxing Zhao
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0042387
Abstract: Background Genetic polymorphisms of the Optic atrophy 1 gene have been implicated in altering the risk of primary open angle glaucoma (POAG), especially the susceptibility to normal tension glaucoma (NTG), but the results remain controversial. Methods Multiple electronic databases (up to January 20, 2012) were searched independently by two investigators. A meta-analysis was performed on the association between Optic atrophy 1 polymorphisms (rs 166850 and rs 10451941) and normal tension glaucoma (NTG)/high tension glaucoma (HTG). Summary odds ratios (ORs) and 95% confidence intervals (CI) were estimated. Results Seven studies of 713 cases and 964 controls for NTG and five studies of 1200 cases and 971 controls for HTG on IVS8+4C>T (rs 166850) and IVS8+32T>C (rs10451941) were identified. There were significant associations between the OPA1 rs10451941polymorphism and NTG susceptibility for all genetic models(C vs. T OR = 1.26, 95% CI 1.09–1.47, p = 0.002; CC vs. TT: OR = 1.52, 95% CI 1.04–2.20, p = 0.029; CC vs. CT+TT: OR = 1.64, 95% CI 1.16–2.33, p = 0.005; CC+CT vs. TT: OR = 1.21, 95% CI 1.02–1.44, p = 0.032). However, no evidence of associations was detected between the OPA1 IVS8+32C>T polymorphism and POAG susceptibility to HTG. Similarly, clear associations between the rs 166850 variant and NTG were observed in allelic and dominant models (T vs. C OR = 1.52, 95% CI 1.16–1.99, p = 0.002; TT+TC vs. CC OR = 1.50, 95% CI 1.13–2.01, p = 0.006) but not to HTG. In subgroup analyses by ethnicity, we detected an association between both OPA1 polymorphisms and risk for NTG in Caucasians but not in Asians. By contrast, no significant findings were noted between OPA1 variants for HTG, either in Caucasians or in Asians. Conclusions Both the IVS8+4C>T and IVS8+32T>C variants may affect individual susceptibility to NTG. Moreover, stratified analyses for NTG detecting the effects of both OPA1 polymorphisms seemed to vary with ethnicity. Further investigations are needed to validate the association.
Huge enhancement of electronmechanical responses in compositionally modulated PZT
Ningdong Huang,Zhirong Liu,Zhongqing Wu,Jian Wu,Wenhui Duan,Binglin Gu,Xiaowen Zhang
Physics , 2003, DOI: 10.1103/PhysRevLett.91.067602
Abstract: Monte Carlo simulations based on a first-principles-derived Hamiltonian are conducted to study the properties of PZT alloys compositionally modulated along the [100] pseudocubic direction near the morphotropic phase boundary (MPB). It is shown that compositional modulation causes the polarization to continuously rotate away from the modulation direction, resulting in the unusual triclinic and C-type monoclinic ground states and huge enhancement of electromechanical responses (the peak of piezoelectric coefficient is as high as 30000 pC/N). The orientation dependence of dipole-dipole interaction in modulated structure is revealed as the microscopic mechanism to be responsible for these anomalies.
Unusual vortex structure in ultrathin Pb(Zr$_{0.5}$Ti$_{0.5}$)O$_3$ films
Zhongqing Wu,Ningdong Huang,Zhirong Liu,Jian Wu,Wenhui Duan,Bing-Lin Gu
Physics , 2004,
Abstract: Using a first-principles-based approach, we determine the ferroelectric pattern in PbZr$_{0.5}$Ti$_{0.5}$O$_3$ ultrathin film. It is found that vortex stripes are formed in the system and they are responsible for the 180$^\circ$ domains observed. When a local external field is exerted, the vortex stripe transforms into the vortex loop structure, which leads to the formation of a smaller domain with the polarization antiparallel to the field in the center of the field region. This may provide a convenient way to manipulate nanodomains in thin films.
Added value of contrast echocardiography in characterization of nonischemic cardiomyopathy
Dong Wang,Lei Huang,Ningdong Kang,Shufang Pi,Tong Li,Wenjin Peng,Yingwu Liu
- , 2018, DOI: 10.1177/0300060518798525
Abstract: Nonischemic cardiomyopathy (NICM) is a group of noncoronary heterogonous myocardial diseases. The heterogonous nature of NICM has impeded its diagnosis. In the present case series, we demonstrate the added value of using contrast echocardiography in the characterization of NICM. Two patients of advanced age were admitted for possible acute coronary syndrome, which was subsequently excluded by coronary angiography. Conventional and contrast echocardiography revealed characteristic structural and dynamic features of the left ventricle that were compatible with two distinct NICM diseases: stress-induced cardiomyopathy and noncompaction of the ventricular myocardium. Contrast echocardiography characterizes the cardiac structure and allows for real-time assessment of myocardial motion and perfusion. It may help to distinguish diseases with different etiologies
Ferroelectricity in Pb(Zr$_{0.5}$Ti$_{0.5}$)O$_{3}$ thin films: critical thickness and 180$^\circ$ stripe domains
Zhongqing Wu,Ningdong Huang,Zhirong Liu,Jian Wu,Wenhui Duan,Bing-Lin Gu,Xiao-Wen Zhang
Physics , 2004, DOI: 10.1103/PhysRevB.70.104108
Abstract: The ferroelectric properties of disorder Pb(Zr$_{0.5}$Ti$_{0.5}$)O$_{3}$ thin films are investigated with Monte Carlo simulations on the basis of a first-principles-derived Hamitonian. It is found that there exists a critical thickness of about three unit cells ($\sim$12 \AA) below which the ferroelectricity disappears under the condition that the in-plane polarizations are suppressed by sufficient clamping effect. Above the critical thickness, periodic $180^{\circ}$ stripe domains with out-of-plane polarizations are formed in the systems in order to minimize the energy of the depolarizaing field. The stripe period increases with increasing film thickness. The microscopic mechanism responsible for these phenomena is discussed.
The Analysis on Financial Cooperative Controlling Mechanism of Enterprise Group  [PDF]
Ziqin Feng
iBusiness (IB) , 2010, DOI: 10.4236/ib.2010.24053
Abstract: As the core of modern market economy, enterprise group is an advanced form of organization after productive forces reached to a certain stage. For the reason of complexity and specificity of organizational form of enterprise group, the issue of financial cooperative control has been widespread concerned by theorists. Although many researches have been done, but there are still lacking of systematic research results especially in the fields of mechanism of financial cooperative control. After exploring the relationship of value effect and financial control, this paper puts forword a system model of financial cooperative control. It also gives a system analysis including system hierarchy analysis, synergy analysis and coupling analysis. All of these can provide a decision making support for the collaborative mana- gement of enterprise group.
Reconfigurable Logistics Information System Based on Soft Components Technology  [PDF]
Feng Liang
Journal of Service Science and Management (JSSM) , 2008, DOI: 10.4236/jssm.2008.12016
Abstract: Logistics information system should be reconfigurable, open and extensible to support the total supply chain. Soft com-ponent technology is introduced to design and build the logistics information system oriented to the business demand of kinds of supply chains. When the supply chain is changed, logistics information system organizes all kinds of required logistics resources, by recalling predefined soft components to dynamically configure logistics information system, which can ensure quick respond to the changes of supply chain demand and support dynamic reconfiguration of the logistics information system. In this paper, a method of reconfiguration of logistics information system by using soft component technology is proposed. The key problems to the subject domain are investigated and an illustrative case study is presented.
Dynamic Neural Network Based Nonlinear Control of a Distillation Column  [PDF]
Feng Li
Intelligent Control and Automation (ICA) , 2011, DOI: 10.4236/ica.2011.24043
Abstract: Taking advantage of the knowledge of top and bottom compositions of a distillation column, a dynamic neural network (DNN) is designed to identify the input-output relationship of the column. The weight-training algorithm is derived from a Lyapunov function. Based on this empirical model, a nonlinear H∞ controller is synthesized. The effectiveness of the control strategy is demonstrated using simulation results.
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