Binding kinetics of monoclonal antibody using antigen-beta-galactosidase hybrid protein: application to measurement of peptide antigenicity

A simple method for determination of binding kinetics of a solid-phase antibody using antigen-beta-galactosidase hybrid protein was evaluated. To minimize conformational change of the antigen binding site of the antibody when directly binding to a microtiter plate, the microtiter plate was precoated with protein A. The binding and free antigen concentrations were directly obtained from the beta-galactosidase activity. This method can be used for analyses of the equilibrium dissociation constant (KD), and the association (Kass) and dissociation (Kdiss) rate constants. Peptide antigenicity was also analyzed by competitive ELISA using this method. Since both antigen-beta-galactosidase and the peptide used are localized in the fluid-phase, the proper affinity constant (KA) of the peptide can be estimated from the KD value of the antigen-beta-galactosidase-antibody interaction, and from the IC50 value of the peptide.     

The use of multiple antigenic peptide (MAP) in the immunodiagnosis of human immunodeficiency virus infection

In order to develop an ELISA system for the antibody detection of HIV-1 or HIV-2 infections, MAPs for HIV-1 gp41(584-618) and HIV-2 gp36(574-602) corresponding to the immunodominant regions of HIV-1 gp41 and HIV-2 gp36 were used as coating antigens in the ELISA. The MAPs were synthesized by the solid phase method using Fmoc-Lys(Fmoc)-OH and their molecular weights were confirmed by tricine gel electrophoresis. The MAPs reacted with all HIV positive sera (64 samples), but did not react with HIV negative sera (48 samples) obtained from healthy blood donors. The MAPs showed high sensitivity and specificity in anti-HIV 1/2 combo panel and anti-HIV-1 seroconversion panels. The results indicated that the ELISA system using synthetic MAPs of gp41(584-618) and gp36(574-602) as coating antigens can be used as an analytical system for the immunodiagnosis of HIV-1 or HIV-2 infections.     

A Framework for MPEG‐4 Contents Delivery over DMB

Digital Multimedia Broadcasting (DMB) is an upcoming standard in Korea used to provide mobile multimedia broadcasting service based on the Eureka‐147 Digital Audio Broadcasting (DAB) system. The current dominant multimedia coding standard, MPEG‐4, is foreseen to play an important role in forthcoming DMB services. However, the current approaches for transporting MPEG‐4 content over DMB networks are not optimized. To address this issue we propose a novel MPEG‐4 stream multiplexer, called M4SMux, which provides better stream multiplexing and delivery over DMB networks. M4SMux features an MPEG‐4 elementary‐stream interleaving mechanism that reduces the multiplexing overhead and a multiplex configuration mechanism that utilizes M4SLinkTable for easy content access. In addition, we propose an error correction method which enhances transport efficiency.     

Deconvolution in the presence of Doppler with application tospecular multipath parameter estimation

High-resolution multipath parameter estimates can be obtained through various deconvolution procedures, all of which-in the limit-rely on some form of inverse filtering. Although deconvolution in a multipath environment free from Doppler is well understood and well documented, this is not true for the case when motion of the multipath components relative to the receiver imposes a Doppler shift on the transmitted probing signal. This paper describes the effect of Doppler on a broad class of deconvolution methods by studying the effect of Doppler on the output of an inverse filter. It is shown that in the presence of Doppler, the deconvolution outputs are comprised chiefly of two signal-related functions, one of which may be designed in such a way as to be free from the range-Doppler coupling effects inherent in correlation processing. Knowledge of these two functions provides insight into the signal design issues relevant to deconvolution-based multipath parameter estimation systems and is useful in designing appropriate constraints and post-processing algorithms that may lead to an accurate extraction of the Doppler and delay parameters of the multipath channel. These results are applied to two known deconvolution methods: the method of projection onto convex sets (POCS) and the method of least squares (LS)     

CDMA Mobile System Testbed and Field Test

This paper briefly explains the configuration of CDMA Mobile System (CMS) test bed. The measured fading and delay results of CDMA signal in Taejon area are shown. In comparison to other cellular systems, there are more parameters in the CDMA systems that affect system performance and capacity. We performed the optimization test of the selected parameters and present the effect of each parameter on the performance. This paper presents the capacity and performance test results of CMS. The capacity test was performed on ETRI site of three sectors in Taejon area. The performance tests include call completion rate, busy hour call attempt, and the delay characteristics of voice.     

Characteristics of Cheonggukjang produced by the rotative fermentation method

This study was to develop a processing method for improving the quality of a fermented soybean food, cheonggukjang. Bacillus sp. AS-2 isolated from traditionally fermented cheonggukjang was selected for the production of cheonggukjang with the rotative fermentation method (RFM). The pH value of cheonggukjang made by RFM (cRFM) was 6.1±0.25. The amount of crude protein (329.0±0.92 mg/g) and amino-type nitrogen (120.6±21.81 mg%) were similar to those in traditionally fermented cheonggukjang (cTFM). The amount of ammonium-type nitrogen was 173.0±1.72 mM/g and nearly 4 times lower than that in cTFM. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging values in the traditional product were between 1.62±0.08 and 1.27±0.05, while with the RFM, the values were between 1.38±0.02 and 0.78±0.20. The antioxidative activity of the sauce-type cRFM was approximately 1.7 times higher than that of cTFM. The sensory scores for cRFM were uniformly higher than those for cTFM.     

Extraction of β-carotene produced from yeast Rhodosporidium sp. and its heat stability

This work determined the characteristics of β-carotene produced from Rhodosporidium sp. isolated from citrus fruits, and an effective extraction method was established. To extract β-carotene from the isolated Rhodosporidium sp., the cell walls were destroyed using dimethyl sulfoxide (DMSO) solution with and without the use of glass beads and a sonicator. Extracted β-carotene was identified by high performance liquid chromatography (HPLC) and liquid chromatography/mass spectrometry (LC/MS) with a β-carotene standard. The yields of β-carotene extracted in DMSO, DMSO and glass beads, and DMSO with a sonicator were 3.371, 5.112, and 3.301 μg/mL, respectively. Isolated β-carotene was relatively heat stable, with 80% of the viable molecules remaining at 80°C.     

Mechanical property changes in drawing/extrusion of hardening viscoplastic materials with damage

This paper is concerned with the mechanical property changes in drawing/extrusion operations of hardening viscoplastic materials with damage. The process model in this study includes two state variables, the hardness for strain hardening from slip dominated plastic distortion and the porosity for damage from growth of microvoids. The decrease in apparent density in strip drawing of aluminum for several die angles are computed and compared with that from experiments. Simulations of axisymmetric drawing/extrusion have shown that the accumulated porosity in drawing is much bigger than that in extrusion while the difference between the hardness distributions in these processes are insignificant. The effects of the process conditions, such as conical die angle, friction and drawing/extrusion speed, on the mechanical property changes are also examined.