• Journal of Ginseng Research
• /
• v.16 no.3
• /
• pp.228-234
• /
• 1992

There has been general tendency to explain the traditional ginseng efficacy through the pharmacological and biochemical activities of ginsenosides. However, when we analyze the pharmacological and biological data on ginseng reported yet, we can easily arrive at the conclsion that most of the data on pharmacological and biological activities must have been obtained using impure ginsenoside samples, which should contain some non-saponin constituents as impurities. Based on the above back-ground, the non-saponin constituents of ginseng were studied in our laboratory. Phenolic substances including Maltol, Vanillic Acid, Salicylic Acid, Ferrulic Acid and Caffeic acid and impure ginsenoside samples were found to show strong antioxidant and anti-fatigue activities, while pure ginsenosides were devoid of the activities. Maltol, one of antioxidant components In Korean red ginseng drew a special interest due to its very low pro-oxidant activity. The antioxidant activity of ginseng may be considered as scientific basis for the antiageing activity which was described in traditional medicinal material book as "long-term medication of ginseng will improve bio-efficiency and extend life-span" The lignin components, another non-saponin consitutents, isolated from ginseng extract In our laboratory may eplain the hepato-protective activity of ginseng which has been repeatedly rtaimed as one of the efficacies of ginsenosides. The P-carboline alkaloids isolated in our laboratory as one of the non-saponin constituents of ginseng may play some pharmacological activities which should also be investigated. Present paper will include chemistry and biochemical aspects of the non-saponin constituents of ginseng with special interests for the explanation of traditional ginseng efficacy on modern scientific basis.fic basis.

• Korean Journal of Veterinary Service
• /
• v.26 no.1
• /
• pp.39-50
• /
• 2003

Non-typhoidal Salmonella serovars remain a potential threat to human health and many animals including beef cattle, broiler chickens, and pigs which possible sources of non-typhoidal salmonellosis in human. In this study, the cecal contents of slaughtered pigs were examined for Salmonella serovar prevalence. The characteristics of the isolates, including antimicrobial resistance patterns and virulence genes, were studied along with the reference strain S typhimurium ATCC 13311. Out of 640 sample, 137 Salmonella(21.4%) were isolated and their serovar were identified S typhimurium 83 strains(60.6%), S agona 10 strains(7.3%), S schwarzengrund 4 strains(2.9%), S derby 4 strains(2.9%), S ayinde 1 strains(0.7%), and untypable 35 strains(25.5%). All 83 S typhimurium strains(100%) were multi-drug resistance to at least 7 antibiotics, and 20 strains(24.1%) of 83 isolates were R-type ACSSuT. Examination of virulent gene by PCR revealed that 73 S typimurium field isolates(88%) have a invA gene and 24 strains(28.9%) have a spvC gene. Consequently, S typhimurium infection in slaughtered pigs was relatively to appear high prevalence in their herds which suggested that it should be necessary for herd health monitoring and surveillance.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.4 no.4
• /
• pp.377-383
• /
• 1999

A new soft switching single stage AC-DC full bridge boost converter with unit input power factor and isolated output i is presented in this paper. Due to the use of a non-dissipative snubber on the primary side, a single stage high-power f factor isolated full bridge boost converter has a significant reduction of switching losses in the main switching devices. The non-dissipative snubber adopted in this study consists of a snubber capacitor Cr, a snubber inductor Cr, a fast r recovery snubber diode Dr' and a commutation diode Dp. This paper presents the complete operating principles, t theoretical analysis and experimental results.

• Earthquakes and Structures
• /
• v.4 no.4
• /
• pp.341-363
• /
• 2013

Earthquake response calculation, parametric analysis and seismic parameter optimization of base-isolated structures are some critical issues for seismic design of base-isolated structures. To calculate the earthquake responses for such non-symmetric and non-classical damping linear systems and to implement the earthquake resistant design codes, a modified complex mode superposition design response spectrum method is put forward. Furthermore, to do parameter optimization for base-isolation structures, a graphical approach is proposed by analyzing the relationship between the base shear ratio of a seismic base-isolation floor to non-seismic base-isolation one and frequency ratio-damping ratio, as well as the relationship between the seismic base-isolation floor displacement and frequency ratio-damping ratio. In addition, the influences of mode number and site classification on the seismic base-isolation structure and corresponding optimum parameters are investigated. It is demonstrated that the modified complex mode superposition design response spectrum method is more precise and more convenient to engineering applications for utilizing the damping reduction factors and the design response spectrum, and the proposed graphical approach for parameter optimization of seismic base-isolation structures is compendious and feasible.

• Biomedical Science Letters
• /
• v.19 no.2
• /
• pp.132-141
• /
• 2013

Mycobacterium isolates were retrospectively identified, antibiotics susceptibility test results and basic clinical data were analyzed for the 715, excepted 308 in 1,023 specimens, from a mycobacterial laboratory at a tertiary care hospital from September 2002 to December 2008. Their male to female ratio was 1.12 to 1 (379 male, 336 female). The median age of study population was 47 years (range from 10 to 93 years). Distribution of Mycobacterium species was 90.1% of total were isolates Mycobacterium tuberculosis, and 9.9% of the total non-tuberculosis Mycobacterium isolated, and Among nontuberculosis Mycobacterium isolates, 60.6% were Mycobacterium avium complex, 14.1% were isolates Mycobacterium abscessus, and 12.7% were isolates Mycobacterium intracellulare. Among 526 Mycobacterium tuberculosis isolates, 81.7% isolates were susceptible to first line antibiotics, 18.3% were resistant to one or more antibiotics. Non-tuberculosis Mycobacterium isolates, all were resistant to two or more antibiotics. Multi-antibiotic resistant tuberculosis rate was show 10.2% of total specimens. Isolated Mycobacterium species, 19.2% were multi-antibiotic resistant tuberculosis, and the rate of nontuberculosis Mycobacterium resistant to isoniazid and rifampin was very highly 84.5%. Thus among acid fast bacilli culture positive cases, Mycobacterium tuberculosis and non-tuberculosis Mycobacterium were must exactly identification and antibiotic sensitivity test. It was considered to help to select of the antibiotic in preventive medicine.

• The Plant Pathology Journal
• /
• v.18 no.2
• /
• pp.63-67
• /
• 2002

To understand plant-pathogen interactions, a complete set of hot pepper genes differentially expressed against pathogen attack was isolated. As an initial step, hundreds of differentially expressed cDNAS were isolated from hot pepper leaves showing non-host resistance against bacterial plant pathogens (Xanthomonas campestris pv. glycines and Pseudomonas syringae pv. syringae) using differential display reverse transcription polymerase chain reaction (DDDRT-PCR) technique. Reverse Northern and Northern blot analyses revealed that 50% of those genes were differentially expressed in pepper loaves during non-host resistance response. Among them, independent genes without redundancy were micro-arrayed for further analysis. Random EST sequence database were also generated from various CDNA libraries including pepper tissue specific libraries and leaves showing non-host hypersensitive response against X. campestris pv. glycines. As a primary stage, thousands of cDNA clones were sequenced and EST data were analyzed. These clones are being spotted on glass slide to study the expression profiling. Results of this study may further broaden knowledge on plant-pathogen interactions.

• Restorative Dentistry and Endodontics
• /
• v.19 no.2
• /
• pp.568-584
• /
• 1994

Bacteria have been regarded as major etiolgic factors in root canal infections. Infected root canal flora from thirteen patients who had visited to conservative department of Wonkwang dental hospital were cultured on blood agar plates. Cultued microorganisms were isolated and identified with Gram stain and biochemical tests using Vitek Systems(BioMeriux, MO, USA); Antibiotic susceptibillity was performed with disk diffusion and broth microdilution using Vitek Systems. Gram positive cocci(65 %) were predominant, which were composed of 6 Streptococcus viridans group, 5 Staph. spp., and 4 Enterococcus faecium, in the isolatd 23 strains. Gram negative rods (26 %) were the next common bacteria, which were composed of 5 non - fermentative Gram negative rods, and 1 Enterobacter cloacae. Most strains of S. viridans group and E. faecium were susceptible to antibiotics including penicillin. But strains of Staphylococcus spp. and non - fermentative Gram negative rods showed marked resistance to antibiotics except tetrancyclin and cefotaxime. Most results between disk diffusion and microdilution were all agreed, but the results of non - fermentative Gram negative rods were susceptible to cefotaxime in disk diffusion method but resistant in microdilution.

• Journal of Environmental Science International
• /
• v.8 no.6
• /
• pp.653-660
• /
• 1999

The flow of non-rotation atmosphere with uniform stratification and wind past an isolated three dimensional topography obstacle is investigated with three-dimensional hydrostatic and non- hydrostatic numerical model. The characteristic of turbulence created the back of topography obstacle is usually defined by Froude number which is the function of upstream wind speed, the height of topography obstacle, and atmospheric stability. Turbulence tends to be formed more easily at the non-hydrostatic model than hydrostatic model. Especially, the difference between flow patterns of two models generated by isolated obstacle is more clear under low Froude number. The difference of flow patterns can be only seen at relatively low altitude, but at high altitude the patterns of two models are almost same. In this research, wind velocity in the parameters related with Froude number have great sensitivity at responsibility of numerical models. and slop of obstacle is also important factor at the flow pattern regardless of the species of numerical model

• Korean Journal of Soil Science and Fertilizer
• /
• v.25 no.4
• /
• pp.394-400
• /
• 1992

In the isolated 280 Actinomycetes strains, 12 groups of Streptomyces were 87.2% and 3groups of Non-Streptomyces were 12.8%, respectively. Streptomyces with sporophore of the spiral chain form reached to 80% of all the Streptomyces isolates. Surface morphology of spores have been determined with the electron microscope ; two groups have a spiny surface, 10 groups have a smooth surface. Isolated Actinomyceles groups were indentified as Streptomycetes groups and Non-Streptomyces groups. Actinomycetes isolates were selected as the strains having predominant antibacterial activities against the microorganisms among the 15 groups which has antibacterial activities. Selected Actinomycetes isolates showed high antibiotic sensitivity of S-9 strain(8.46 r/ml), S-6 strain(6.23 r/ml), S-2 strain(7.24 r/ml) against Pseudomonas aeruginosa (ATCC 27857), Escherichia coli (ATCC 25922) and Staphylococcus aureus(ATCC 6538).

• The Transactions of the Korean Institute of Power Electronics
• /
• v.14 no.4
• /
• pp.315-322
• /
• 2009

In the conventional boost converter, the actual duty cycle is limited as the output voltage increases due to increased voltage and current stress of the switch and diode and voltage surge caused by diode reverse recovery. In this paper a new non-isolated boost converter suitable for high gain applications is proposed. The proposed converter has voltage gain of around 6 when the duty cycle is 0.5. Since ZVS is achieved under CCM, the proposed converter has wide ZVS range. Also, voltage ratings of switch and diode are the same as one third of output voltage, and ratings of input and output passive components are reduced due to the interleaving. In addition voltage surge caused by diode reverse recovery is negligible due to ZCS turn-off of diodes. Operating principle of the proposed converter is described and validated through theoretical analysis, simulation and experiment.