Biography:

One of their most recent publications is Research reportSuppression of nociceptive responses in parafascicular neurons by stimulation of substantia nigra: an analysis of related inhibitory pathways. Which was published in journal Brain Research.

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

Jun Li's Articles: (167)

Research reportSuppression of nociceptive responses in parafascicular neurons by stimulation of substantia nigra: an analysis of related inhibitory pathways

AbstractA total of 166 neurons in parafascicular nucleus (PF) were studied, 85 from intact animals, 72 following dorsal spinal cord transection (D.Sp.C.X.) and 9 following complete transection of the spinal cord. Two patterns of nociceptive response were identified following noxious stimulation and these responses were classified as ‘nociceptive-off’ and ‘nociceptive-off’ neurons, respectively. The effect of stimulating the substantia nigra (SNS) on the spontaneous and on the nociceptive evoked discharges were observed and compared in intact, D.Sp.C.X. and completely transected spinal cord rats. The results show that SNS significantly suppresses both the spontaneous and the nociceptive evoked discharge elicited by peroneal nerve stimulation. With an intact spinal cord, SNS suppressed both the spontaneous [−37±3.2.% (P < 0.05)] and the nociceptive evoked discharges [−52.8±2.8% (P < 0.01)] of the the same stimulation elicited an even more prominent suppression upon both discharges (−4.7.±5.4.%, P < 0.01 and −64.9±5.0%, P < 0.01), respectively. After D.Sp.C.X., the suppressive effects on the ‘nociceptive-on’ cells following SNS were diminished (−28.1±3.5% and −36.9±2.6%, respectively) but not abolished, while in the ‘nociceptive-off’ cells, the inhibitory effects on SNS were unchanged. In addition, the suppressive effects of SNS on the spontaneous activity of PF neurons in cases with completely cut spinal cords remains unchanged. These results suggest that SNS modulates the spontaneous and the noxious evoked responses of the PF neurons by way of supraspinal connections besides the previously described descending projecting pathways.

Ab initio studies on the electronic structures of certain 10π-electron six-membered ring compounds

AbstractBy using ab initio methods of all-electron or effective core potential calculations, the electronic structures and the possible aromaticity of some 10π-electron systems, C6H64− (1), N64− (2), P64− (3), S62− (4), Te62− (5) and S3N3− (6), have been studied at the SCF levels using 4-31G//4-31G and 6-31G∗//6-31G∗ basis sets. The bonding characteristics of these systems are analysed in terms of the canonical molecular orbital and the Foster-Boys localized molecular orbital results. The application of the second-order Jahn-Teller theorem to the stability of these diamagnetical planar species is presented.

Effects of ion size, ion valence and pH of electrolyte solutions on EOF velocity in single nanochannels

Highlights•The electroosmotic flow is systematically studied in nanochannels as small as 85 nm.•The hydrated size of counterions has significant effects on electroosmotic flow velocity in small nanochannels.•The flow reversal for electroosmotic flow with multivalent ions is demonstrated experimentally for the first time.•The pH dependence of electroosmotic flow velocity is experimentally measured in nanochannels.

Brief paperRobust control reconfiguration of resource allocation systems with Petri nets and integer programming☆

AbstractSupervisory control reconfiguration can handle the uncertainties including resource failures and task changes in discrete event systems. It was not addressed to exploit the robustness of closed-loop systems to accommodate some uncertainties in the prior studies. Such exploitation can cost-efficiently achieve reconfigurability and flexibility for real systems. This paper presents a robust reconfiguration method based on Petri nets (PNs) and integer programming for supervisory control of resource allocation systems (RASs) subject to varying resource allocation relationships. An allocation relationship is seen as a control specification while the execution processes requiring resources as an uncontrolled plant. First, a robust reconfiguration mechanism is proposed. It includes updating the P-invariant-based supervisor and evolving the state of the closed-loop system. The latter adapts to the control specification changes by the self-regulation of the closed-loop system’s state. Next, two novel integer programming models for control reconfiguration are proposed, called a reconfiguration model with acceptability and reconfiguration one with specification correction. Since both models integrate the firability condition of transitions, no additional efforts are required for the state reachability analysis. Finally, a hospital emergency service system is used as an example to illustrate them.

MicroRNA-194 promotes osteoblast differentiation via downregulating STAT1

Highlights•Overexpression of miR-194 significantly increased osteoblast differentiation.•miR-194 directly targeted the 3′- UTR of STAT1.•miR-194 regulated the expression of STAT1.•Overexpression of miR-194 promoted the nuclear translocation of Runx2.

miR-7-5p acts as a tumor suppressor in bladder cancer by regulating the hedgehog pathway factor Gli3

AbstractAlthough important progresses have been made in the diagnosis and treatment of bladder cancer (BCa), the overall survival for patients with advanced BCa remains poor. It is necessary to uncover the molecular mechanism underlying the initiation and progression of bladder cancer. According to previous reports, mircoRNAs (miRNAs) can regulate tumorigenesis by targeting their downstream mRNAs. This study aims to explore and analyze a novel miRNA-mRNA axis which can regulate the progression of bladder cancer. Based on the microarray analysis, 182 mRNAs were found to be upregulated in BCa tissues. Gene oncology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that these upregulated mRNAs are related with hedgehog pathway. Gli3, an important factor of hedgehog pathway, belongs to these 182 upregulated mRNAs. Therefore, Gli3 was chosen to do further study. Kaplan-Meier analysis revealed that highly expressed Gli3 predicted unfavorable prognosis for patients with BCa. Results of functional experiments indicated the inhibitory effects of silenced Gli3 on cell proliferation, migration and EMT progress. Mechanically, Gli3 was the target mRNA of miR-7-5p in BCa cells. Finally, rescue assays were performed to validate the specific function of miR-7-5p/Gli3 axis in BCa progression. According to all data, we concluded that miR-7-5p acts as a tumor suppressor in BCa by downregulating Gli3.

Research ReportThe pre-ischaemic neuroprotective effects of the polyamine analogues BU43b and BU36b in permanent and transient focal cerebral ischaemia models in mice

AbstractThe present study investigated the neuroprotective potential of two novel polyamine analogues, BU43b and BU36b, when administered 30 min prior to cerebral ischaemia. Neuroprotection in a permanent and a transient focal cerebral ischaemia mouse model (induced by intraluminal middle cerebral artery occlusion (MCAO)) was investigated using a range of histological and behavioural assessments. In the permanent ischaemia model, BU43b reduced oedema and showed a trend towards reduction in %HLV (percentage hemisphere lesion volume) when administered at a dose of 30 mg/kg i.p. Following transient ischaemia, treatment with BU43b decreased the %HLV and reduced oedema when administered at 30 mg/kg. BU43b also improved the locomotor activity (LMA) in MCAO mice at both 20 mg/kg and 30 mg/kg doses. BU36b was less effective than BU43b in both the permanent and the transient models, with its most pronounced effect being a trend towards reduction in oedema in both models. These results demonstrate that BU43b administered 30 min before ischaemia provided a good level of neuroprotection in the two models of cerebral ischaemia used and may have potential as a neuroprotective treatment for stroke.

Conformational analysis of an α-galactosyl trisaccharide epitope involved in hyperacute rejection upon xenotransplantation

Abstractα-Galactosyl epitopes are carbohydrate structures bearing an α-Gal-(1→3)-Gal terminus (α-Gal epitopes). The interaction of these epitopes on the surface of animal cells with anti α-Gal antibodies in human serum is believed to be the main cause in antibody-mediated hyperacute rejection in xenotransplantation. In this paper, conformational analysis of an N-linked α-d-Galp-(1→3)-β-d-Galp-(1→4)-β-d-Glcp trisaccharide epitope was conducted in terms of each monosaccharide residue conformation, primary hydroxymethyl group configuration, and interglycosidic conformations. Selective 2D J-δ INEPT experiments have been carried out at three different temperatures to evaluate three-bond, long-range 13C–1H coupling constants for the crucial α-(1→3) linkage. The NMR experimental data were complemented by theoretical calculations. The flexibility and dynamics of the trisaccharide have been studied by Metropolis Monte Carlo simulations. Ensemble-averaged three-bond, long-range 13C–1H coupling constants and nuclear Overhauser effects were in good agreement with the experimental data. The α-(1→3) glycosidic linkage has shown a restricted flexibility as indicated by NMR spectroscopy and molecular modeling.

Modeling of a packed-bed electrochemical reactor for producing glyoxylic acid from oxalic acid

AbstractA two-dimensional reactor model was established for a packed-bed electrochemical reactor with cooled cathode (PERCC) for producing glyoxylic acid from oxalic acid based on the system's reaction kinetics, mass conservation equation, and the equation of charge conservation in terms of solution-cathode potential to describe the distributions of glyoxylic acid concentration and electrolyte potential in the cathode compartment of the PERCC. The equation for a circulating mixer was also presented to account for the accumulation of glyoxylic acid in the catholyte of a batch electroreduction process. Using the orthogonal collocation approach, the partial differential equations of the model could be converted into sets of algebraic equations and be numerically solved. The effects of operating temperature, conductivity of catholyte, operating cathode potential, and volumetric flow rate of the catholyte on the current efficiency and concentration of glyoxylic acid were simulated and discussed, with emphasis on the current densities generated from main and side reactions. The model was used in a batch operation process and a continuous operation process, with the predicted results being generally in good agreement with the experimental data for both the cases.

Lightweight wrinkle synthesis for 3D facial modeling and animation☆

Highlights•We present a lightweight non-parametric approach to generate wrinkles for 3D facial modeling and animation.•Our method represents a convenient approach for generating plausible facial wrinkles with low-cost.•Our method enables the reconstruction of captured expressions with wrinkles in real-time.

Synthesis and characterization of polypyrrole/nickel hydroxide/sulfonated graphene oxide ternary composite for all-solid-state asymmetric supercapacitor

AbstractThe polypyrrole/nickel hydroxide/sulfonated graphene oxide (PPy/Ni(OH)2/SGO) ternary composite is prepared as supercapacitor electrode material by stepwise loading of Ni(OH)2 and PPy into SGO through hydrothermal and chemical oxidative polymerization process. The PPy and Ni(OH)2 are incorporated into composite to act as pseudocapacitive electrode with low cost and high capacitance. The SGO obtained by the surface modification of graphene has a higher hydrophilic property and larger specific surface to provide charge transfer path. The creative PPy/Ni(OH)2/SGO (P-N-S) ternary composite shows a high specific capacitance of 1632.5 F g−1 at a current density of 1 A g−1 in 6 M KOH solution. A capacitance retention of 86% after 1000 cycles proves that the P-N-S has a good cycling stability. The all-solid-state asymmetric supercapacitor (ASC) is assembled with P-N-S cathode material and activated carbon (AC) as anode material to exhibit a high special capacitance of 224 F g−1 at 1 A g−1, a large energy density (79.6 Wh Kg−1) and power density (0.8 kW kg−1), and a stable cycle life (the capacitance retention rate of 60% after 5000 cycles at 10 A g−1). Two ASCs in series can lighten up a green LED indicator.

RETRACTED: Synthesis and electrochemical characterization of MWCNTs-improved Li3V2(PO4)3/C as cathode material for lithium-ion batteries with extremely high capacity

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy).This article has been retracted at the request of Editor-in-Chief.At the end of August 2015 the Editorial Office of Electrochimica Acta received a message from the corresponding author of this paper stating that he never submitted this manuscript to the journal. Upon inquiry it was found that the initial version of the manuscript had been submitted to the journal from the EES account of J.C. Zheng ([email protected]), College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, PR China. Nevertheless, J.C. Zheng is non-existent and was never employed by the School of Chemistry and Chemical Engineering of Chongqing University. Moreover, the revised version of the article was submitted to Elsevier with a different authorship, including a new email address for the corresponding author ([email protected]). The email address of the corresponding author was then changed to the one given in the published version of the article upon proof correction.As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to the authors of the published version and the readers of the journal.

Volumetric combustion of biomass for CO2 and NOx reduction in coal-fired boilers

AbstractTo meet the urgent environmental targets, substituting coal with biomass has been considered to be an effective and promising method over the last decades. In this paper, a new concept of volumetric combustion is proposed and further developed to achieve 100% fuel switching to biomass in large scale coal-fired boilers. Volumetric combustion not only changes the in-furnace flow but also affects the combustion reactions by the intensive mixing and internal recirculation of the flue gases. Firstly, the volumetric combustion properties of the wood pellets were investigated experimentally. An Aspen model was then used to thermodynamically describe and study the volumetric combustion with three different types of fuel, and the emission properties of CO2 and NOx were compared. Finally, two applications of volumetric combustion were discussed. It is concluded that the wood pellets ignited and combusted much faster than the coal pellets and had a larger combustion volume when combusted under lower oxygen concentration conditions, and the ignition time was almost independent of the oxygen concentration when the oxidizer was preheated to 1000 °C. In addition, the NOx emissions decreased as the recirculation ratio of the flue gas increased, and as the percentage of biomass used in co-firing increased, the amount of flue gas that needs to be recycled for reduction of NOx decreased. Thus, the volumetric combustion is beneficial as it reduces the operation cost of NOx reduction. The volumetric combustion would be an attractive technology for co-firing a large proportion of biomass in coal-fired boilers with high boiler efficiency and effective emissions reduction.

Characterization of high-temperature rapid char oxidation of raw and torrefied biomass fuels

Highlights•The char oxidations of two biomass chars were tested in an Isothermal Plug Flow Reactor.•Reactivity of raw biomass char is compared with that of torrefied biomass char.•The char oxidation kinetic parameters are determined using a parameter optimization method.•Determined kinetics are examined by comparing the experimental and predicted mass conversions.

Dynamic behaviors of premixed hydrogen–air flames in a planar micro-combustor filled with porous medium

Highlights•Premixed hydrogen-air combustion in a planar micro-combustor was studied.•Flame stability limits for different combustor configurations were identified.•Porous medium was found to be effective in enlarging the operation window.•Blow-off limits are nearly independent of combustor configurations.•Flashback limits are greatly influenced by the parameters of the porous medium.

Prediction of high-temperature rapid combustion behaviour of woody biomass particles

AbstractBiomass energy is becoming a promising option to reduce CO2 emissions, due to its renewability and carbon neutrality. Normally, biomass has high moisture and volatile contents, and thus its combustion behaviour is significantly different from that of coal, resulting in difficulties for large percentage biomass co-firing in coal-fired boilers. The biomass combustion behaviour at high temperatures and high heating rates is evaluated based on an updated single particle combustion model, considering the particle size changes and temperature gradients inside particle. And also the apparent kinetics determined by high temperature and high heating rate tests is employed to predict accurate biomass devolatilization and combustion performances. The time-scales of heating up, drying, devolatilization, and char oxidation at varying temperatures, oxygen concentrations, and particle sizes are studied. In addition, the uncertainties of swelling coefficient and heat fractions of volatile combustion absorbed by solid on the devolatilization time and total combustion time are discussed. And the characterised devolatilization time and total combustion time are finally employed to predict the biomass combustion behaviour. At the last, a biomass combustion/co-firing approach is recommended to achieve a better combustion performance towards large biomass substitution ratios in existing coal-fired boilers.

Experimental study on standing wave regimes of premixed H2–air combustion in planar micro-combustors partially filled with porous medium

Highlights•Filtration combustion of premixed H2–air in planar micro-combustors is conducted.•Critical conditions corresponding to the standing wave regimes are identified.•Effects of various parameters on the standing wave regime are investigated.•Combustor size has a significant influence on the standing wave regime.•With the increase of combustor size, the standing wave regime shrinks rapidly.

Simulation of macrosegregation in a 2.45-ton steel ingot using a three-phase mixed columnar-equiaxed model

AbstractA three-phase mixed columnar-equiaxed solidification model is used to calculate the macrosegregation in a 2.45 ton steel ingot. The main features of mixed columnar-equiaxed solidification in such an ingot can be quantitatively modelled: growth of columnar dendrite trunks; nucleation, growth and sedimentation of equiaxed crystals; thermosolutal convection of the melt; solute transport by both convection and crystal sedimentation; and the columnar-to-equiaxed transition (CET). The predicted as-cast macrostructure and the segregation pattern are in qualitative agreement with the reported experimental results. Parameter study on the numerical grid size and the nucleation of the equiaxed crystals are performed, and some segregation mechanisms are numerically analyzed. Discontinued positive–negative segregation just below the hot top is predicted because of the formation of a local mini-ingot and the subsequent sedimentation of equiaxed grains within the mini-ingot. Quasi A-segregates in the middle radius region between the casting outer surface and the centreline are also found. The quasi A-segregates originate from the flow instability, but both the appearance of equiaxed crystals and their interaction with the growing columnar dendrite tips significantly strengthen the segregates. The appearance of equiaxed phase is not a necessary condition for the formation of quasi A-segregates. The quantitative discrepancy between the predicted and experimental results is also discussed.

Pseudo-optimal measures

AbstractBased on a pseudo-addition ⊕ on [0, ∞], pseudo-optimal measures related to non-negative set functions vanishing at the empty set (non-negative games) are introduced. For a fixed pseudo-addition ⊕, an equivalence ∼⊕ on non-negative set functions is studied. A special stress is given to pure pseudo-optimal measures, admitting no other ∼⊕ equivalent set function.

Perioperative glucocorticosteroid treatment delays early healing of a mandible wound by inhibiting osteogenic differentiation

AbstractAimThe purpose of this study is to investigate the effects of dexamethasone on repair of a critical size defect of the mandible in male Sprague-Dawley rats.Materials and methodsFifty rats were divided into 2 groups: saline control and dexamethasone-treated groups. A 1 mm × 3 mm full-thickness bone defect was created at the inferior border of the mandible. Saline or dexamethasone was administered once a day for 5 days after postoperative palinesthesia. On days 1, 3, 6, 10 and 17, after cessation of drug administration, 5 samples from each group were analysed. The bone defect healing process was examined and analysed by stereology, radiology, histology and histochemical staining for total collagen, tartrate-resistant acid phosphatase staining for osteoclasts and immunohistochemical staining for the COX-2, RUNX2 and osteocalcin antigens.ResultsThe dexamethasone-treated rats exhibited significantly lower radiopacity properties compared to the control rats. Histological staining revealed that the osteogenic differentiation and maturation of a callus in the defect region was significantly delayed from day 1 to day 10 in the dexamethasone group after cessation of drug administration compared to the control group. Consistent with the histological data, the level of total collagen protein was significantly lower in the dexamethasone group than in the control group. However, there was no significant difference between the 2 groups at day 17. Immunohistochemical analysis of COX-2, RUNX2 and osteocalcin expression showed that, at day 1, COX-2 and RUNX2 expression in the dexamethasone group was significantly lower than in the control group. There was no significant difference in osteocalcin expression between the two groups at each time point. There was no significant difference in the number of osteoclasts between the two groups.ConclusionIn a model of bone healing of a mandible defect, dexamethasone-treated rats exhibited impaired osteogenic differentiation and maturation due to the inhibition of COX-2, osteogenic gene, RUNX2 and collagen protein expression, which resulted in delayed bone repair. Although perioperative short-term therapy did not exhibit long-term effects on wound healing of the maxillofacial bone, the application of glucocorticoids should be cautiously considered in the clinic.

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