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  • Author: Yuan-Yuan He x
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Optimization of Emulsifying Effectiveness of Phytosterol in Milk Using Two-Level Fractional Factorial Design

Abstract

In this paper emulsifying effects of seven emulsifiers including Tween 80, Span 80, tripolyglycerol monostearate, sodium stearoyl lactylate, sucrose ester, soy lecithin and monoglyceride on phytosterol in milk were investigated using single factor test and fractional factorial design. The addition for seven emulsifiers were in the following concentrations: 0.1%, 0.2%, 0.3%, 0.4%, 0.5% and 0.6%. The results revealed that tripolyglycerol monostearate, sucrose ester and monoglyceride had a significant emulsifying effect on phytosterol in milk, Tripolyglycerol monostearate showed a positive emulsifying effect on phytosterol in milk, while sucrose ester and monoglyceride exhibited a negative emulsifying effect on phytosterol in milk.

Open access
An Experimental Study on the Mechanisms of Ge Hua Jie Cheng Decoction for Rats with Alcoholic Liver Injuries

Abstract

Objective: To explore the effects and underlying mechanisms of Ge Hua Jie Cheng Decoction on rats with alcoholic liver injuries.

Methods: 60 Wistar rats were randomly assigned to six groups: normal group, model group, Yi Gan Ling group, and Ge Hua Jie Cheng Decoction groups in low, middle and high concentrations, 10 rats in each group. Except for the normal group, rats in other groups were administered white wine for eight weeks to establish the liver injury model. During the modeling, the Yi Gan Ling/Ge Hua Jie Cheng Decoction were administered intragastrically to the rats. So the histopathological changes were observed after eight weeks, meanwhile the serum γ- glutamyl endopeptidase (GGT), Glutathione (GSH) and aspartate aminotransferase mitochondrial isoenzyme (m-AST) were assayed by automatic biochemical analyzer.

Results: under the light microscope, the groups of high and middle dosages of Ge Hua Jie Cheng Decoction , especially the high one, had apparent improvement of inflammatory infiltration in liver tissues. Compared with the normal group, the serum GGT and m-AST levels had elevated (P<0.01), whereas the serum GSH level decreased (P<0.01); compared with model group, the high and middle dosages of Ge Hua Jie Cheng Decoction groups had decreased serum GGT and m-AST (P<0.01 or P<0.05), as well as increased serum GSH level (P<0.01).

Conclusion: Ge Hua Jie Cheng Decoction has a protective effect for liver injuries induced by alcohol, and this effect is dose-dependent. The high dosage showed stronger protection effect, which might be related to the increased serum GSH and decreased serum GGT and m-AST.

Open access
Camera Calibration by Hybrid Hopfield Network and Self- Adaptive Genetic Algorithm

A new approach based on hybrid Hopfield neural network and self-adaptive genetic algorithm for camera calibration is proposed. First, a Hopfield network based on dynamics is structured according to the normal equation obtained from experiment data. The network has 11 neurons, its weights are elements of the symmetrical matrix of the normal equation and keep invariable, whose input vector is corresponding to the right term of normal equation, and its output signals are corresponding to the fitting coefficients of the camera’s projection matrix. At the same time an innovative genetic algorithm is presented to get the global optimization solution, where the cross-over probability and mutation probability are tuned self-adaptively according to the evolution speed factor in longitudinal direction and the aggregation degree factor in lateral direction, respectively. When the system comes to global equilibrium state, the camera’s projection matrix is estimated from the output vector of the Hopfield network, so the camera calibration is completed. Finally, the precision analysis is carried out, which demonstrates that, as opposed to the existing methods, such as Faugeras’s, the proposed approach has high precision, and provides a new scheme for machine vision system and precision manufacture.

Open access
Auto Mission Planning System Design for Imaging Satellites and Its Applications in Environmental Field

Abstract

Satellite hardware has reached a level of development that enables imaging satellites to realize applications in the area of meteorology and environmental monitoring. As the requirements in terms of feasibility and the actual profit achieved by satellite applications increase, we need to comprehensively consider the actual status, constraints, unpredictable information, and complicated requirements. The management of this complex information and the allocation of satellite resources to realize image acquisition have become essential for enhancing the efficiency of satellite instrumentation. In view of this, we designed a satellite auto mission planning system, which includes two sub-systems: the imaging satellite itself and the ground base, and these systems would then collaborate to process complicated missions: the satellite mainly focuses on mission planning and functions according to actual parameters, whereas the ground base provides auxiliary information, management, and control. Based on the requirements analysis, we have devised the application scenarios, main module, and key techniques. Comparison of the simulation results of the system, confirmed the feasibility and optimization efficiency of the system framework, which also stimulates new thinking for the method of monitoring environment and design of mission planning systems.

Open access
Toll-like receptor-4, but not toll-like receptor-2 mediates secretion of tumour necrosis factor α and interleukin-8 in lipopolysaccharide-stimulated mouse mammary epithelial cells

Abstract

Mammary epithelial cells (MECs) from Kunming mice were isolated and stimulated in vitro with 10 μg/mL of Escherichia coli lipopolysaccharide (LPS). The release of tumour necrosis factor α (TNF-α) and interleukin-8 (IL-8) into culture supernatants was measured by ELISA. Furthermore, blocking experiments with Toll-like receptor 2 (TLR2) and TLR4 antibodies were performed to verify whether cytokine secretion depended on LPS-induced activation of TLR2 or TLR4. The results revealed that LPS-stimulated mouse MECs significantly secreted TNF-α and IL-8. Blocking of the TLR4 pathway inhibited the secretion of TNF-α and IL-8, while inhibition of LPS-induced TNF-α and IL-8 production was not observed when TLR2 was blocked. Thus, TLR4 can mediate the LPS-induced expression of cytokines such as TNF-α and IL-8 in mouse MECs.

Open access
Optimization of Fermentation Conditions for the Production of Angiotensin-Converting Enzyme (ACE) Inhibitory Peptides from Cow Milk by Lactobacillus bulgaricus LB6

Abstract

The purpose of this research was to screen out the optimal -producing peptide conditions for cow milk fermented by Lactobacillus bulgaricus LB6. The effects of temperature, inoculation size, time and skim milk concentration on the ACE inhibition rate of fermented milk were investigated by single factor experiment, and the optimal fermentation conditions were determined by orthogonal experiment. The conditions of the single factor experiment were: Temperatures were 37° C, 39° C, 42° C, 44° C and 46° C. The inoculation amount was 1%, 3%, 5%, 7% and 9%, the time was 8h and 10h. At 12h, 14h and 16h, the concentration of skim milk was 8%, 10%, 12%, 14% and 16%, respectively. The results showed that the optimal fermentation conditions for ACE inhibitory peptide produced by Lactobacillus bulgaricus LB6 were 4% inoculation, 13h in time, 42°C in temperature and 13% in skim milk. Under this condition, the ACE inhibition rate reached 76.50% and the OD value was 0.330. The titration acidity was 116.4°T, the pH was 4.62, and the sensory evaluation was 75 scores.

Open access
Analysis and Simulation on the Effect of Rotor Interturn Short Circuit on Magnetic Flux Density of Turbo–Generator

Abstract

The intent of this paper is to investigate the effect of the interturn short circuit fault (ISCF) in rotor on the magnetic flux density (MFD) of turbo-generator. Different from other studies, this work not only pays attention to the influence of the faulty degrees on the general magnetic field, but also investigates the effect of the short circuit positions on the harmonic components of MFD. The theoretical analysis and the digital simulation through the FEM software Ansoft are performed for a QSFN-600-2YHG turbo-generator. Several significant formulas and conclusions drawn from the analysis and the simulation results are obtained to indicate the relation between the harmonic amplitude of the MFD and the faulty degree (via nm, the number of the short circuit turns), and the relation between the MFD harmonic amplitude and the faulty position (via αr, the angle of the two slots in which the interturn short circuit occurs). Also, the developing tendency of the general magnetic field intensity, the distribution of the magnetic flux lines, and the peak-to-peak value of MFD are presented.

Open access
An Outbreak of SARS in a Diabetes Room of a General Hospital without Infected Medical Staff

Abstract

Objective To investigate the epidemiologic features of an outbreak of SARS that occurred in a single diabetes room of a general hospital in Beijing in late March 2003.

Methods Field investigation was carried out in the ward, the nursing log and the hospitalization medical record of correlative patients were consulted. SARS-CoV in serum specimen from SARS patient was detected by PCR.

Results The room where SARS outbreak occurred was on the 13th floor of the 16-story main ward building. There were 6 beds in the room, living with 6 female patients (aged 45-67) who were all hospitalized due to type 2 diabetes. On March 24, 2003, Patient 1 began to have a fever and cough, chest X-ray showed pneumonia. Five and six days later, Patient 2 and Patient 3 began to have a fever, respectively. Finally, all of these 3 patients died. Their beds were all at the same side of the room, and the other 3 patients at the opposite side were not infected. Serum SARS CoV-RNA of the Patient 3 was positive by nest-PCR. The daughter-in-law of Patient 1 who accompanied Patient 1 by the bedside several days, mainly near the window, upwind of Patient 1, was not infected. Medical staff, family members and visitors of the 6 patients were not infected.

Conclusions This outbreak was not transmitted by aerosol. The distance droplets travels could be up to 3.43 meters. Droplet spread has direction, and the droplets direction of propagation is closely related with the wind direction and speed. Those at the downwind position of SARS patients were susceptible to be infected. Medical staff wore face masks and good natural ventilation of this ward building may be important reasons for the prevention of infection.

Open access
The Relationship between Intrahepatic Distribution of Hepatitis B Virus Core Antigen and Serum ALT, HBV DNA Levels and HBeAg Status

Abstract

Objective The clinical significance of differential distribution of hepatitis B virus (HBV) nucleocapsid antigen in hepatocytes remains unknown. The goal of this study is to determine the relationship between distinct HBV core antigen distribution pattern and alanine transaminase (ALT), liver histological inflammatory activity grades, serum HBeAg status and HBV DNA level.

Methods Total of 958 cases with chronic hepatitis B were recruited into this study. Liver function tests, serum HBV DNA level, serological HBV markers and liver immunohistochemistry were examined according to the conventional instructions. Chi Square tests were performed to analyze the differences among these groups.

Results It was found that 552 (58%) cases were tested positive for HBV core antigen by immunohistochemical staining. Cytoplasmic hepatitis B core antigen (HBcAg) expression correlated with ALT level and serum HBV DNA and liver inflammatory activity scores, however, nuclear HBcAg expression in hepatocytes was associated with normal ALT level, lower liver inflammatory activity score and higher serum HBV DNA level and rate of HBeAg positivity. Both nuclear and cytoplasmic HBcAg expression in hepatocytes associated with a middle ALT level and liver inflammatory activity score, higher rate of serum detectable HBeAg and a higher HBV DNA level. However, undetectable core antigen was related to a lower ALT level and histological inflammatory activity grade, lower positive HBeAg rate and HBV DNA level.

Conclusions Undetectable liver HBcAg is associated with HBV clearance, ALT normalization and hepatitis B e antigen (HBeAg) seroconversion, and cytoplasmic HBcAg expression associated with higher hepatic inflammatory activity. However, nuclear HBcAg expression correlates with immune tolerance characterized with normal ALT and lower liver inflammatory activity, higher HBV replication level and higher rate of HBeAg positivity.

Open access
Development of a new RT-PCR with multiple primers for detecting Southern African Territories foot-and-mouth disease viruses

Abstract

Introduction: The extremely high genetic variation and the continuously emerging variants of foot-and-mouth disease virus (FMDV) of Southern African Territory (SAT) serotypes including SAT1, SAT2, and SAT3 make it necessary to develop a new RT-PCR for general use for monitoring viruses based on the updated genome information.

Material and Methods: A FMDV SAT-D8 one-step RT-PCR was established based on the 1D2A2B genes of the SAT serotype viruses with a multiplex primer set. FMDV A, O, C, and Asia 1 serotypes, other vesicular disease viruses, inactivated SAT viruses, and 125 bovine, ovine, caprine and porcine tissue samples collected from the Chinese mainland were included for evaluating the assay.

Results: The new RT-PCR was proven to be specific without cross-reactions with Eurasian FMDV, swine vesicular disease virus (SVDV), Seneca valley virus (SVV), or other common viral pathogens of cattle, sheep, goat, and pig. An around 257 bp-sized amplicon clearly appeared when the inactivated SAT viruses were detected. However, all 125 samples collected from FMDV-susceptible animals from the Chinese mainland which has not known SAT epidemics showed negative results.

Conclusions: A FMDV SAT-D8 one-step RT-PCR is a promising method for primary screening for FMDV SAT serotypes.

Open access