Biography:

One of their most recent publications is Plant chemistryIridoids in roots of Pedicularis chinensis. Which was published in journal Phytochemistry.

More information about Yang Li research including statistics on their citations can be found on their Copernicus Academic profile page.

Yang Li's Articles: (144)

Plant chemistryIridoids in roots of Pedicularis chinensis

AbstractFour new iridoids, the glucosides 3β-butoxy-3,4-dihydroaucubin, 6-O-butyl-aucubin and 6-O-butyl-epiaucubin, together with pedicularis-lactone were isolated from roots of pedicularis chinensis. In addition, the known glucosides aucubin and bartsioside and a known iridoid lactone were also isolated. The compounds were identified mainly by spectral evidence.

Short communicationIdentification of cDNAs encoding bovine cyclin B and Cdk1/Cdc2

AbstractcDNA sequences encoding homologs of cyclin B and Cdk1/Cdc2 were isolated from bovine blastocyst-stage embryos produced in vitro. The bovine CycB sequence is 1548 nucleotides (nt) in length and contains the conserved motif ‘FLRRXSK’, characteristic for known cyclin B proteins. The deduced protein contains 427 amino acids (aa) and has an estimated mass of 47653 Da. The bovine cdkl/cdc2 sequence is 1275 nt in length and contains the highly conserved motif ‘EGVPSTAIREISLLKE’. The deduced protein contains 297 aa (33931 Da).

Stress-field pinning induced by lattice mismatch in Y-123 superconductors

AbstractA pinning mechanism of a stress field has been proposed in high-Tc superconductors. The studies focus on the interaction between magnetic flux and lattice mismatch induced by substitution of Ho for Y in YBa2Cu3O7−δ. By establishing an effective defect model, the stress distribution, centered on the substitutional dopant Ho, is briefly described. Moreover, a calculation on the pinning strength has been performed for the flux lines in such a stress field. The calculated result further demonstrates that rare-earth dopants for Y can become the effective pinning centers under the appropriate doping level.

4 - Fluid flow law in fracture-vug carbonate reservoir

AbstractComplex reservoir space and different-scale flow channels in the fracture-vug carbonate reservoir result in complex flow law and flow mechanism, involving one-dimensional (1D) pipe flow, 2D flow on the fracture surface, 3D flow in unfilled (or semi-filled) vugs and caves, and other flow patterns among vugs, caves, fractures, and matrix. Understanding the fluid flow law in a fracture-vug reservoir and those among different media is the basis for the scientific development of the fracture-vug reservoir. According to the characteristics of the fracture-vug reservoir, the physical modeling similarity criterion group has been established, multitype typical fracture-vug models have been built, macrophysical simulation experiment devices for fracture-vug media have been designed, and physical simulation experiments and research for fluid flow mechanisms have been carried out systematically. The systematical experiment of one-phase flow has demonstrated the one-phase flow features and the transformation conditions in the reservoir space in different types of fracture-vug reservoir, based on which one-phase flow equations have been established. The systematical oil–water two-phase flow experiment has determined the two-phase flow features and relative permeability curves, and accordingly two-phase flow patterns, based on which two-phase flow equations have been developed. In addition, the interporosity flow law among different types of reservoir has been revealed, which provides the foundation for the development of the numerical simulation technology.

MiscellaneousAcute Aortic Dissection in China

The clinical profiles and outcomes of acute aortic dissection (AAD) have not been evaluated in China. We retrospectively analyzed, from January 1, 2008 to December 31, 2011, the data from 1,812 patients (mean age 51.1 ± 10.9 years; 77.5% men) with AAD (726 with type A and 1,086 with type B) from 19 large hospitals. Most patients had hypertension and presented with an abrupt onset of chest and/or back pain. Patients with type A AAD were more likely to present with typical symptoms and signs. Computed tomography was the most common initial imaging modality, used in 76.3% of patients with an AAD. The overall in-hospital mortality rate was 17.7%, with most of the deaths occurring within the first week. Surgery was used in 75.3% of patients with type A AAD. The mortality in this cohort was 33.8%. Endovascular treatment was performed in 76.1% of patients with type B AAD. The mortality rate was 2.2%. Multivariate analysis showed that hypertension (odds ratio 2.80, p <0.001), Marfan syndrome (odds ratio 1.76, p = 0.017), anterior chest pain (odds ratio 1.62, p = 0.004), abdominal pain (odds ratio 1.51, p = 0.041), migrating pain (odds ratio 1.56, p = 0.04), and arch vessel involvement (odds ratio 1.70, p <0.001) were predictive factors for increased in-hospital mortality in patients with an AAD. In conclusion, our study has provided insight into the current profiles and outcomes of AAD in China. This knowledge might be useful for clinicians when diagnosing and treating these patients.

A new method based on counterpropagation network algorithm for chemical pattern recognition

AbstractThis paper develops an approach for chemical pattern recognition realized by using a modified counterpropagation network (CPN). Combining Kohonen network and least mean-square (LMS) learning enables the modified CPN algorithm to solve the supervised type classification problem. First, patterns are separated into subgroups in which there are no samples of different categories. The Kohonen layer of neurons is used to establish the clusters. During the training process the updating of weights deals with merely winning neurons in stead of a domain of neurons as done in the standard counterpropagation network (SCPN) algorithm. Second, based on the obtained subgroups patterns of the same category are grouped together by LMS in the output layer. Thus the proposed method yields a piecewisely linear discriminant boundary for classification. Compared with the existing methods the proposed procedure is competent for more complex problems of classification and efficiently lightens the computational burden of network training. Experimental investigations of simulated and real data sets showed that the proposed method outperformed standard linear discriminant analysis (SLDA) method in the cases of partially linear inseparability. Compared with the conventional neural work methods, i.e. the standard backpropagation network (BPN) and SCPN, it also showed better learning efficiency and classification performance.

Klotho down-regulates Egr-1 by inhibiting TGF-β1/Smad3 signaling in high glucose treated human mesangial cells

Highlights•High glucose time-dependently down-regulated Klotho mRNA and protein expression in cultured human MCs.•Klotho overexpression down-regulated Egr-1 and prevented mesangial ECM production in high-glucose-treated human MCs.•Klotho down-regulated Egr-1 by inhibiting TGF-β1/Smad3 signaling in high-glucose-treated human MCs.

NoteX-ray crystal structure of iridoid glucoside aucubin and its aglycone

AbstractX-ray diffraction analyses of iridoid glycoside aucubin (1) and its aglycone aucubigenin (2) are reported. It was found that crystals of 1 are orthorhombic, with P212121 space group, both cyclopentane ring and pyran ring adopt envelope conformations, and the Glc moiety is in the 4C1 conformation. Crystals of 2 are monoclinic, with space group P21, the cyclopentane and pyran rings also adopt the envelope conformation. The absolute configurations of 1 and 2 were also determined. Intensive O–H⋯O hydrogen bonds in both crystal lattices were observed.

High performance nanoporous carbon microsupercapacitors generated by a solvent-free MOF-CVD method

AbstractMicro power sources that support higher power capabilities, specific energies, and ultra-long cycling lifetimes are required for next generation microelectro-mechanical systems (MEMS) and miniaturized portable microdevices. We demonstrated a simple, solvent-free method to coat interdigitated gold electrodes with a conformal layer of nanoporous carbon. Initially the electrodes were coated with a film of ZnO via electrodeposition to serve as the zinc source. These films were exposed to 2-methylimidazole vapor to transform the ZnO into a metal organic framework (MOF) called ZIF-8. The thickness of the ZnO film and the duration of the MOF conversion process created ZIF-8 films with different morphologies, cross-sections and elemental compositions. The ZIF-8 films were then carbonized at 800 °C under a flowing environment of N2 gas to generate nanoporous carbon film electrodes for supercapacitors. The devices have superior capacitance retention, in addition to high power and energy densities. Our 16-electrode microsupercapacitor had a stack power of 232.8  W⋅cm−3, which could be attained even at a scan rate of 1000 V ⋅s−1, without rapid stack energy attenuation. The process of combining an inexpensive ZnO electrodeposition method with solvent-free MOF deposition and subsequent carbonization generates high surface area carbon electrodes with good electrochemical performance.

Research paperThermal properties and cycling performance of Ca(BH4)2/MgH2 composite for energy storage

Highlights•A method is proposed to choose hydrides for thermal storage or hydrogen storage.•The PCI curves of Ca(BH4)2/MgH2 are reported for the first time.•The Ca(BH4)2/MgH2 dehydrogenation enthalpy is calculated by Van’t Hoff and DSC.•NbF5 enhances the reversibility of Ca(BH4)2/MgH2 composite.

Ecological assessment of executive functions in adolescents genetically at high risk for schizophrenia

AbstractObjectiveThis study sought to examine specific executive deficits in the real-life environment among adolescents genetically at high risk for schizophrenia and understand the role of the genetic risk, victimization and family functioning, and their interaction on the deficits.MethodsThe study included 96 non-affected adolescent offspring and siblings of patients with schizophrenia in the high-risk group (HR) and 193 healthy adolescents in the healthy control group (HC), all aged between 9 and 20 years. All participants completed assessments of executive functions (EFs), victimization, and family functioning.ResultsThe multivariate analysis revealed that the HR group reported more difficulties on the Shift, Plan/Organize, and Task Completion scale than the HC group. Significant main effects were also detected for victimization level on all domains of EFs and for adaptability level on Inhibit, Working Memory, Plan, and Task Completion scales. Besides, the group × victimization level interactions were significant for Working Memory and Task Completion scales. Hierarchical regression analysis revealed that the genetic risk and victimization were predictors of executive deficits.ConclusionsThe HR group showed impaired EFs in the everyday environment. And, the genetic risk for schizophrenia and victimization may be related to executive dysfunction. Our results may provide clues about explaining the mechanisms of executive impairments in the HR group and help to identify new targets for early interventions.

Effect of catalysts on the reactivity and structure evolution of char in petroleum coke steam gasification

Highlights•The effect of catalysts on petroleum coke reactivity in steam gasification was tested.•Raman spectra and X-ray spectra analyzed the evolution of aromatic and crystallite structure of petroleum coke.•The mechanism of catalytic gasification of petroleum coke was explored in depth.

Full Length ArticleDevelopment of a reduced four-component (toluene/n-heptane/iso-octane/ethanol) gasoline surrogate model

AbstractThe prospect of blending gasoline fuel with ethanol is being investigated as a potential way to improve the knock residence of the base gasoline. However, one of the drawbacks is a lack of proper understanding of the reason for the non-linear response of blending ethanol and gasoline. This non-linearity could be better understood by an improved knowledge of the interactions of these fuel components at a molecular level. This study proposed a highly reduced four-component (toluene/n-heptane/iso-octane/ethanol) gasoline surrogate model containing 59 species and 270 reactions. The model was reduced using the direct relation graph with expert knowledge (DRG-X) (Lu and Law, 20015; Lu et al., 2011) and isomer lumping method. The computational singular perturbation (CSP) analysis were performed to reduce the potential stiffness issues by accordingly adjusting the Arrhenius coefficients of the proper reactions. The model has been comprehensively validated against wide range of ignition delay times (IDT) and flame speed (FS) measurement data as well as compared against two representative literature models from Liu et al. (2013) and Wang et al. (2015). Overall, good agreements were observed between model predictions and experimental data across the entire research octane number (RON), equivalence ratio, pressure and temperature range. In addition, the model has also been coupled with the computational fluid dynamic (CFD) models to simulate the experimental data of constant volume reacting spray of a low-octane gasoline (Haltermann straight-run naphtha), and in-cylinder pressures and temperatures of a high-octane gasoline (Haltermann Gasoline) combustion in a heavy duty compression ignition engine. The coupled model can qualitatively predict the experimentally obtained data with an improved performance for PRF, TPRF, and TPRF-ethanol surrogates.

Heat transfer characteristics in a rotating trailing edge internal cooling channel with two coolant inlets

Highlights•Two-inlet cooling structure is introduced for trailing edge cooling channel.•The parabolic relations between MR and overall averaged Nu ratios are correlated.•Two-inlet inflow reduces rotational effect on trailing-to-leading heat transfer difference.•A critical MR is observed in rotating channel to determine low-radius leading heat transfer.•The coupling effect of rotation and MR dominates rotational heat transfer distribution.

Heat transfer performance in a rotating two-inlet cooling wedge-shaped channel with lateral inflow holes

Highlights•Single lateral coolant inflow brings positive effect on heat transfer of low-radius.•The optimized mass flow ratios are found at a range of 0.3–0.7 at stationary.•The critical mass flow ratio phenomenon is observed and explained.•Two-inlet cooling scheme improves rotational surface averaged heat transfer.

Heat transfer enhancement of X-lattice-cored sandwich panels by introducing pin fins, dimples or protrusions

Highlights•Dimples, protrusions and pin fins are introduced into X-lattice sandwich panels.•Mechanisms of fluid flow and heat transfer by the introduced elements are analyzed.•Introducing pin fins in Region A exhibits the best overall heat transfer performance.•A proper combination of the X-lattice and heat transfer enhancement elements is desired.

Research articlePositive observer design for switched positive T–S fuzzy delayed systems with dwell time constraints

Highlights•Observer design problem is first addressed for both measurable and unmeasurable cases.•An optimized observer is computed for the unmeasurable case.•Less conservative stability conditions.

Disentangled Variational Auto-Encoder for semi-supervised learning

AbstractSemi-supervised learning is attracting increasing attention due to the fact that datasets of many domains lack enough labeled data. Variational Auto-Encoder (VAE), in particular, has demonstrated the benefits of semi-supervised learning. The majority of existing semi-supervised VAEs utilize a classifier to exploit label information, where the parameters of the classifier are introduced to the VAE. Given the limited labeled data, learning the parameters for the classifiers may not be an optimal solution for exploiting label information. Therefore, in this paper, we develop a novel approach for semi-supervised VAE without classifier. Specifically, we propose a new model called Semi-supervised Disentangled VAE (SDVAE), which encodes the input data into disentangled representation and non-interpretable representation, then the category information is directly utilized to regularize the disentangled representation via the equality constraint. To further enhance the feature learning ability of the proposed VAE, we incorporate reinforcement learning to relieve the lack of data. The dynamic framework is capable of dealing with both image and text data with its corresponding encoder and decoder networks. Extensive experiments on image and text datasets demonstrate the effectiveness of the proposed framework.

Clinical articleIncorporating uterine artery embolization in the treatment of cesarean scar pregnancy following diagnostic ultrasonography

AbstractObjectiveTo evaluate combining uterine artery embolization (UAE) with other treatments for cesarean scar pregnancy (CSP).MethodsA retrospective study included patients attending the First affiliated Hospital of Xi'an Jiaotong University, China, between March 1, 2009 and March 31, 2014, who were diagnosed with CSP. Patients were classified by ultrasonography as having endogenous CSP (CSP type I [CSP-I]) or exogenous CSP (CSP type II [CSP-II]). Patient outcomes were compared between patients who underwent treatment that included or excluded UAE. Patient records were reviewed and patients were interviewed by telephone to report on recovery following treatment.ResultsIn total, 52 patients met the inclusion criteria. In patients with CSP-I, the blood loss, length of hospital stay, and time before restoration of normal β human chorionic gonadotropin levels were significantly higher in patients who were treated with methotrexate combined with dilatation and curettage compared with those treated with UAE combined with dilatation and curettage (P < 0.05). In patients with CSP-II, blood loss was lower in patients treated with UAE combined with excision compared with excision alone (P < 0.001).ConclusionIncorporating UAE in the treatment of CSP-I and CSP-II was safe; CSP should be properly classified to select the appropriate treatment.

External inversion of thin-walled corrugated tubes

Highlights•The introduction of corrugation to the thin-walled tubes makes the inversion of such tubes far less sensitive to surface imperfections and requires no lubrication.•The findings have greatly extended the utilisation of the inversion mechanism in practical applications.

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