A convenience UPLC/PDA method for the quantitative analysis of panaxfuraynes A and B from Panax ginseng

Panaxfurayne A and B, biologically novel tetrahydrofuranic polyacetylene glycosides, were founded from roots of Panax ginseng C. A. Meyer (Araliaceae). To study the contents of panaxfurynes A and B, a quantitative analysis method was developed using ultra performance liquid chromatography (UPLC) coupled with photo diode array detector. The dried (65 °C, 72 h) and powdered sample (5 g) was extracted with ethanol (15%, 100 ml) for 30 min at 50 °C and concentrate. The constituents were separated using an isocratic mobile phase consisting acetonitrile (16%) in water for 10 min on a ODS column. The contents of panaxfuraynes A and B in the roots of Panax quinquefolium, Panax japonicum, Panax notoginseng and P. ginseng were found to less than 3 and 2 ng/g approximately, respectively. The constituents were not detected from P. japonicum.     

Effects of rice koji inoculated with Aspergillus luchuensis on the biochemical and sensory properties of a sailfin sandfish (Arctoscopus japonicus) fish sauce

The effects of rice koji inoculated with Aspergillus luchuensis on the biochemical and sensory properties of fish sauce produced from sailfin sandfish (Arctoscopus japonicus) with different salt concentrations (10% and 20%) were investigated over 10 months. Fish sauces prepared from sailfin sandfish with rice koji and a low salt concentration had higher total nitrogen, amino nitrogen and total free amino acid than did those without rice koji or with a high salt concentration. Sensory evaluation of fish sauces prepared with rice koji and a low salt concentration found better taste, flavour and overall acceptance than those prepared without rice koji during fermentation (P < 0.05). The use of rice koji increased the total nitrogen, amino nitrogen and free amino acid and also enhanced the sensory qualities during fermentation. These results suggest that the use of rice koji can result in a low‐salt fish sauce with better flavour.     

A risk management approach to safety assessment of trenchless technologies for culvert rehabilitation

Proper functioning of culverts is not only critical to protecting the transportation system from flooding but also critical to maintaining the expected service life of the overall transportation system. During the service life of culverts, they deteriorate due to many reasons such as corrosion caused by road salt, blockage by debris and sediment, poor construction techniques, etc. Trenchless technologies have been used by several State Departments of Transportation (DOTs) to rehabilitate deteriorated drainage structures without disrupting the traffic and within a relatively short span of time. These technologies provide many benefits in terms of cost, time, quality, and expected service life. However, the safety aspects of these techniques have not been discussed and documented in detail probably due to the complexity and the lack of safety standards and specifications directly associated with the techniques. This paper discusses the application of a risk assessment framework to assess potential safety issues of currently available trenchless technologies for culvert rehabilitation. The findings of the study will provide additional information to improve the decision making process in selecting and planning culvert rehabilitation projects.     

Kinetic model of glycerol chlorination with hydrochloric acid

A new reaction model for dichloropropanol (DCP) synthesis from glycerol chlorination is proposed based on the models reported by Tesser et al. (2007) and Luo et al. (2009). Two reaction steps, glycerol to glycerol-1-acetate and α-MCP to 3-chloropropandiol-1-acetate, were defined as reversible reactions and other reaction steps were defined as irreversible processes. Using the experimental data reported by Luo et al. (2009), the values predicted in this study were compared with the previous model reported by Luo et al. (2009) using both the average absolute deviation (AAD) and root mean square deviation (RMSD). The AAD and RMSD of the new model were 31% and 33% lower than that of the existing one, respectively. Overall, the proposed model for glycerol chlorination is superior to the previous model.     

Wear behavior of self-lubricating Fe-Cr-C-Mn-Cu alloys: Smearing effect of second phase particles

Newly developed self-lubricating Fe-Cr-C-Mn-Cu cast composite alloys were investigated to study the role of Cu-rich second phase particles which smear on the wear surface during sliding. The wear resistance of the material was improved with an increasing copper concentration. The improved wear resistance was probably obtained by forming a protective tribofilm, which prevented metal-to-metal contact through smearing of the embedded Cu-rich second phase particles. This formation of protective oxide films during sliding is likely to improve the wear resistance of austenitic Fe-Cr-C-Mn-Cu cast composite alloys.     

Gas-phase separations of protein and peptide ion fragments generated by collision-induced dissociation in an ion trap

Ion mobility/time-of-flight mass spectrometry techniques have been used to examine distributions of fragment ions generated by collision-induced dissociation (CID) in a quadrupole ion trap. The mobility-based separation step prior to mass-to-charge (m/z) analysis reduces spectral congestion and provides information that complements m/z-based assignments of peaks. The approach is demonstrated by examining fragmentation patterns of insulin chain B (a 30-residue peptide), and ubiquitin (a protein containing 76 amino acids). Some fragments of ubiquitin show evidence for multiple stable conformations.     

Real-time gaze control of an active head-eye system without calibration

This article describes real-time gaze control using position-based visual servoing. The main control objective of the system is to enable a gaze point to track the target so that the image feature of the target is located at each image center. The overall system consists of two parts: the vision process and the control system. The vision system extracts a predefined color feature from images. An adaptive look-up table method is proposed in order to get the 3-D position of the feature within the video frame rate under varying illumination. An uncalibrated camera raises the problem of the reconstructed 3-D positions not being correct. To solve the calibration problem in the position-based approach, we constructed an end-point closed-loop system using an active head-eye system. In the proposed control system, the reconstructed position error is used with a Jacobian matrix of the kinematic relation. The system stability is locally guaranteed, like image-based visual servoing, and the gaze position was shown to converge to the feature position. The proposed approach was successfully applied to a tracking task with a moving target in some simulations and some real experiments. The processing speed satisfies the property of real time. This work was presented in part at the Sixth International Symposium on Artificial Life and Robotics, Tokyo, January 15–17, 2001     

A synchronization algorithm for distributed multimedia environments

Network synchronization plays a significant role in transmitting multimedia objects over computer networks. Even packets from a single channel must be synchronized due to the problems in a packet switching environment, such as network jitter, frequency, and time offsets. We present an algorithm that determines the set of packets generated periodically by various participants arriving at a node. The basic advantage of the proposed algorithm is that the receiver estimates the reference times (expected arrival times of the packets) and achieves synchronization, without knowledge of the packet delays. The accuracy is improved and the complexity is reduced by predicting the time/frequency offsets between the clocks at the source and the mixer. The error is calculated by the Chernoff bound, demonstrated by simulation, and shown to be acceptable in practical applications.     

Internal pressures and thermal pressure coefficients for solid polymers

The temperature and pressure dependence of the thermal pressure coefficient and internal pressure for eight polymer solids are calculated. The principal results are as follows: (1) The pressure dependence of the thermal pressure coefficient at constant temperature is relatively small. (2) For some solid polymers, as a function of temperature, a maximum in the thermal pressure coefficient is predicted in the solid region, and the temperatures corresponding to the maximum values are estimated. (3) For most solid polymers, the zeropressure internal pressure increases with increasing temperature over the entire temperature range to the glass transition temperature or the melting point. © 1995 John Wiley & Sons, Inc.