Showing papers by "Nanchang University published in 2008"

Eosin Y-sensitized nitrogen-doped TiO2 for efficient visible light photocatalytic hydrogen evolution

Abstract: A nitrogen-doped TiO2 (N-TiO2) photocatalyst was prepared by the calcination of the hydrolysis product of Ti(SO4)2 with aqueous ammonia. Pt was loaded on N-TiO2 by photodeposition method. A dye-sensitization photocatalyst was prepared by impregnation method with Eosin Y and the platinized N-TiO2. The prepared samples were characterized by XRD, UV–vis diffuse reflectance spectra (DRS), BET and FT-IR. The visible light activity of the sensitization photocatalysts was evaluated by photocatalytic hydrogen evolution (λ > 420 nm) in the presence of electron donor triethanolamine (TEOA). The N-TiO2 has smaller crystalline size and larger specific surface area to enhance the adsorption amount of Eosin Y than TiO2 prepared by NaOH. Surface oxygen defects produced by nitrogen doping would improve the adsorption of Eosin Y and excited electron to transfer to the conduction band of N-TiO2. Therefore the visible light activity of the sensitized nitrogen-doped platinized TiO2 is much higher than that of the sensitized platinized TiO2. The sensitized nitrogen-doped platinized TiO2 calcined at 300 °C has the highest visible light activity among the catalysts calcined at various temperatures, whose activity is increased by a factor of 3 compared to that of the sensitized platinized TiO2 calcined at the same temperature.

Clinical Characteristics of 26 Human Cases of Highly Pathogenic Avian Influenza A (H5N1) Virus Infection in China

Abstract: Background: While human cases of highly pathogenic avian influenza A (H5N1) virus infection continue to increase globally, available clinical data on H5N1 cases are limited. We conducted a retrospective study of 26 confirmed human H5N1 cases identified through surveillance in China from October 2005 through April 2008. Methodology/Principal Findings: Data were collected from hospital medical records of H5N1 cases and analyzed. The median age was 29 years (range 6–62) and 58% were female. Many H5N1 cases reported fever (92%) and cough (58%) at illness onset, and had lower respiratory findings of tachypnea and dyspnea at admission. All cases progressed rapidly to bilateral pneumonia. Clinical complications included acute respiratory distress syndrome (ARDS, 81%), cardiac failure (50%), elevated aminotransaminases (43%), and renal dysfunction (17%). Fatal cases had a lower median nadir platelet count (64.5610 9 cells/L vs 93.0610 9 cells/L, p=0.02), higher median peak lactic dehydrogenase (LDH) level (1982.5 U/L vs 1230.0 U/L, p=0.001), higher percentage of ARDS (94% [n=16] vs 56% [n=5], p=0.034) and more frequent cardiac failure (71% [n=12] vs 11% [n=1], p=0.011) than nonfatal cases. A higher proportion of patients who received antiviral drugs survived compared to untreated (67% [8/12] vs 7% [1/14], p=0.003). Conclusions/Significance: The clinical course of Chinese H5N1 cases is characterized by fever and cough initially, with rapid progression to lower respiratory disease. Decreased platelet count, elevated LDH level, ARDS and cardiac failure were associated with fatal outcomes. Clinical management of H5N1 cases should be standardized in China to include early antiviral treatment for suspected H5N1 cases.

Position and Orientation Characteristic Equation for Topological Design of Robot Mechanisms

Abstract: This paper presents the explicit mapping relations between topological structure of parallel mechanism and position and orientation characteristic (in short, POC) of its motion output link. It deals with: (1) The symbolic representation and the invariant of topological structure of mechanism; (2) The matrix representation of POC of motion output link; (3) The POC equations of parallel mechanism and its symbolic operation rules. The symbolic operation involves simple mathematic tools and fewer operation rules, and has clear geometrical meaning. So, it is easy to use. The forward operation of the POC equations can be used for structural analysis; its inverse operation can be used for structural synthesis. The method proposed in this paper is totally different from the methods based on screw theory and based on displacement subgroup.Copyright © 2008 by ASME

Differences in 12‐Lead Electrocardiogram Between Symptomatic and Asymptomatic Brugada Syndrome Patients

Abstract: Introduction: Brugada syndrome (BrS) is an inherited disorder that predisposes some subjects to sudden cardiac death (SCD). It is not well established which BrS patients are at risk of severe arrhythmias. Our aim was to study whether standard 12-lead electrocardiogram (ECG) would give useful information for this purpose. Methods: This study included 200 BrS probands (142 male, 62%; mean age 42 ± 16 years). Symptoms related to BrS were defined as syncope, documented ventricular tachyarrhythmia, or SCD. We determined PR, QRS, QTc, Tpeak, and Tend interval from leads II and V2 and QRS from lead V5, R′/S ratio from lead aVR (aVR sign), QRS axis, and J-point elevation amplitude from right precordial leads from the baseline ECGs. Results: Sixty-six subjects (33%) had experienced symptoms related to BrS. The only significant difference between the symptomatic and asymptomatic BrS subjects was the QRS duration measured from lead II or lead V2, for example, the mean QRS in V2 was 115 ± 26 ms in symptomatic versus 104 ± 19 ms in asymptomatic patients (P < 0.001). The optimized cut-off point of V2 QRS ≥120 ms gave an odds ratio (OR) of 2.5 (95% CI: 1.4–4.6, P = 0.003) for being symptomatic. In a multivariate analysis adjusted with gender, age, and SCN5A mutation, the OR was 2.6 (95% CI: 1.4–4.8, P = 0.004). Conclusion: Prolonged QRS duration, measured from standard 12-lead ECG, is associated with symptoms and could serve as a simple noninvasive risk marker of vulnerability to life-threatening ventricular arrhythmias in BrS.

Lower Semicontinuity of the Set of Efficient Solutions for Generalized Systems

Abstract: We discuss the lower semicontinuity of the set of efficient solutions for parametric generalized systems with monotone bifunctions in real locally convex Hausdorff topological vector spaces.

Continuity of the Solution Set to Parametric Weak Vector Equilibrium Problems

Abstract: In this paper, we obtain some stability results for parametric weak vector equilibrium problems in topological vector spaces. We provide sufficient conditions for the continuity of the solution set mapping in parametric weak monotone vector equilibrium problems.

Thermal Properties of Heat Conductive Silicone Rubber Filled with Hybrid Fillers

Abstract: The thermal conductivities of vinyl endblocked polymethylsiloxane reinforced with silicone nitride (Si3N4) particles alone or in combination with silicone carbide whisker (SiCw) were investigated in this article. The results indicate that the silicone rubber incorporating of 50 vol% hybrid Si3N4 particles of different sizes at an optimal weight ratio exhibited the highest thermal conductivity of 1.48 W/m K compared to each single particle size filler used only; moreover, the combined use of hybrid Si3N4 and SiCw with the weight ratio of 9:1 provided the composites with higher thermal conductivity due to the structuring filler in hybrid fillers, improved thermal stability and reduced coefficient of thermal expansion (CTE) for comparison with the hybrid Si3N4 particles used alone. In addition, the surface treatment of the hybrid fillers with 3-methacryloyloxy-propyltrimethoxysilane enhanced the thermal conductivity and reduced CTE of the composites.

Scavenging and anti-fatigue activity of fermented defatted soybean peptides

Abstract: Many bioactive peptides possess specific biological properties that make these potential ingredients of health-promoting foods. Increasing attention is being focused on physiologically active peptides derived from soybean proteins. In this study, soybean peptides were produced by fermentation of defatted soybean meal with Bacillus subtilis SHZ and purified by ultrafiltration and gel chromatogram. Free radical scavenging property and the effect on anti-fatigue of the peptides were evaluated in vitro and in vivo, respectively. Swimming endurance tests of mice were carried out after 20 days of soybean peptides administration (0, 100, 200, 400 mg/kg BW/day for control, low-dose, middle-dose and high-dose group, respectively). And the blood lactate and hepatic glycogen of mice were determined. Results showed that the purified peptides exhibited significant (P < 0.01) scavenging potencies on superoxide (62%) and hydroxyl (96%) at a concentration of 10 mg/ml. The average swimming time of the low-, middle- and high-dose group was increased by 20.91, 45.45 and 70% compared with that of control group, respectively. And administration with soybean peptides could significantly accelerate the clearance of blood lactate after mice swimming (P < 0.01). The hepatic glycogen storage of middle and high dose groups were obviously increased (P < 0.05). It suggested that the soybean peptides produced by fermentation could significantly alleviate physical fatigue of the mice.

A Modified FCM Algorithm for MRI Brain Image Segmentation

Abstract: Image segmentation is often required as a preliminary and indispensable stage in the computer aided medical image process, particularly during the clinical analysis of magnetic resonance (MR) brain image Fuzzy c-means (FCM) clustering algorithm has been widely used in many medical image segmentations However, the conventionally standard FCM algorithm is sensitive to noise because of not taking into account the spatial information To overcome the above problem, a modified FCM algorithm (called mFCM later) for MRI brain image segmentation is presented in this paper The algorithm is realized by incorporating the spatial neighborhood information into the standard FCM algorithm and modifying the membership weighting of each cluster The proposed algorithm is applied to both artificial synthesized image and real image Segmentation results not only on synthesized image but also MRI brain image which degraded by Gaussian noise and salt-pepper noise demonstrates that the presented algorithm performs more robust to noise than the standard FCM algorithm

Effects of dietary probiotic supplementation on ileal digestibility of nutrients and growth performance in 1- to 42-day-old broilers

Abstract: This study was conducted to determine the effects of dietary probiotic supplementation on the ileal digestibilities of nutrients and growth performance in broilers. Two thousand, eight hundred and eighty male broiler chickens at 1 day of age were randomly allotted to eight treatment groups and fed for 6 weeks the maize–soybean meal-based diets containing 0, 0.2, 0.4 or 0.6% AgiPro A100® (a probiotic) and 0 or 6 ppm flavomycin (an antibiotic). This well-established antibiotic was used as a positive control for the efficacy of AgiPro A100®. Dietary supplementation with either the probiotic or the antibiotic alone did not affect (P > 0.05) feed intake or average daily gain (ADG) of broilers between days 1 and 42 of life. However, there was a significant antibiotic × probiotic interaction effect (P < 0.05) in increasing ADG during the entire experimental period. Notably, dietary supplementation with the probiotic or the antibiotic consistently improved (P < 0.05) the ileal digestibilities of crude protein and most amino acids in 21- and 42-day-old chickens. Supplementing the probiotic to broiler diets also improved (P < 0.05) the ileal digestibilities of dry matter, energy, calcium and phosphate in the birds. Collectively, these results indicated that AgiPro A100® is an effective alternative to flavomycin in chicken production. Copyright © 2007 Society of Chemical Industry

A high γ-aminobutyric acid-producingLactobacillus brevis isolated from Chinese traditionalpaocai

Abstract: To find a high γ-aminobutyric acid-producing lactic acid bacterium, more than 1000 strains of lactic acid bacteria isolated frompaocai samples in various areas of China were screened by the ability in production of γ-aminobutyric acid, analysed with paper chromatography, HPLC and HPLC-MS. Among them, one strain NCL912 exhibited high ability to convert sodium glutamate to γ-aminobutyric acid. The strain accumulated 149.05 mM of γ-aminobutyric acid in a modified MRS medium containing 3% sodium glutamate after 48 h of static cultivation at 30 °C. This strain was identified asLactobacillus brevis according to its phenotypic and phylogenetic characteristics.

Inhibitory effect of electrolyzed reduced water on tumor angiogenesis

Abstract: Vascular endothelial growth factor (VEGF) is a key mediator of tumor angiogenesis. Tumor cells are exposed to higher oxidative stress compared to normal cells. Numerous reports have demonstrated that the intracellular redox (oxidation/reduction) state is closely associated with the pattern of VEGF expression. Electrolyzed reduced water (ERW) produced near the cathode during the electrolysis of water scavenged intracellular H(2)O(2) and decreased the release of H(2)O(2) from a human lung adenocarcinoma cell line, A549, and down-regulated both VEGF transcription and protein secretion in a time-dependent manner. To investigate the signal transduction pathway involved in regulating VEGF expression, mitogen-activated kinase (MAPK) specific inhibitors, SB203580 (p38 MAPK inhibitor), PD98059 (ERK1/2 inhibitor) and JNKi (c-Jun N-terminal protein kinase inhibitor) were applied. The results showed that only PD98059 blocks VEGF expression, suggesting an important role for ERK1/2 in regulating VEGF expression in A549 cells. As well, ERW inhibited the activation of extracellular signal-regulated kinase (ERK) in a time-dependent manner. Co-culture experiments to analyze in vitro tubule formation assay revealed that A549 cell-derived conditioned medium significantly stimulated the formation of vascular tubules in all analyzed parameters; tubule total area, tubule junction, number of tubules, and total tubule length. ERW counteracted the effect of A549 cell-conditioned medium and decreased total tube length (p<0.01). The present study demonstrated that ERW down-regulated VEGF gene transcription and protein secretion through inactivation of ERK.

Resurvey of order and chaos in spinning compact binaries

Abstract: This paper is mainly devoted to applying the invariant, fast, Lyapunov indicator to clarify some doubt regarding the apparently conflicting results of chaos in spinning compact binaries at the second-order post-Newtonian approximation of general relativity from previous literatures. It is shown with a number of examples that no single physical parameter or initial condition can be described as responsible for causing chaos, but a complicated combination of all parameters and initial conditions is responsible. In other words, a universal rule for the dependence of chaos on each parameter or initial condition cannot be found in general. Chaos does not depend only on the mass ratio, and the maximal spins do not necessarily bring the strongest effect of chaos. Additionally, chaos does not always become drastic when the initial spin vectors are nearly perpendicular to the orbital plane, and the alignment of spins cannot trigger chaos by itself.