• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1541-1542
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• 2013

• Structural Engineering and Mechanics
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• v.55 no.5
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• pp.1001-1014
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• 2015

Bending analysis of functionally graded (FG) nano-plates is investigated in the present work based on a new sinusoidal shear deformation theory. The theory accounts for sinusoidal distribution of transverse shear stress, and satisfies the free transverse shear stress conditions on the top and bottom surfaces of the plate without using shear correction factor. The material properties of nano-plate are assumed to vary according to power law distribution of the volume fraction of the constituents. The size effects are considered based on Eringen's nonlocal theory. Governing equations are derived using energy method and Hamilton's principle. The closed-form solutions of simply supported nano-plates are obtained and the results are compared with those of first-order shear deformation theory and higher-order shear deformation theory. The effects of different parameters such as nano-plate length and thickness, elastic foundation, orientation of foundation orthtotropy direction and nonlocal parameters are shown in dimensionless displacement of system. It can be found that with increasing nonlocal parameter, the dimensionless displacement of nano-plate increases.

• Archives of Pharmacal Research
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• v.28 no.7
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• pp.761-764
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• 2005

Indigin, alkylated xanthene (1) and indigoferic acid (2) have been isolated from the chloroform soluble fraction of Indigofera oblongifolia, along with $\beta$-sitosterol (3) and 3-hydroxybenzoic acid (4), which are reported for the first time from this species. Their structures were determined through spectroscopic techniques. Both the new compounds 1 and 2 showed significant activity against enzyme lipoxygenase, while 2 further showed moderate inhibition against BChE.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.167-170
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• 2007

(-)-Epigallocatechin-3-gallate (EGCG), a mai or tea catechin has been shown to have many interesting biological activities. In the present study, we studied the effects of green tea catechins, EGCG metabolites, and black tea theaflavins on accumulation of EGCG in HT-29 human colon cells. Intracellular levels of [$^3H$]-EGCG were not changed significantly in the presence of other tea catechins including (-)-epicatechin, (-)-epigallocatechin, and (-)-epicatechin-3-gallate. EGCG methyl metabolites and EGCG 4"-glucuronide did not affect cellular levels of [$^3H$]-EGCG. Black tea theaflavins and theasinensin A (TsA), an EGCG oxidative dimer, however, significantly decreased cellular accumulation of EGCG in HT-29 cells by 31-56%. This decrease was more pronounced when cells were incubated in the presence of theaflavin-3',3"-digallate (TFdiG) or TsA. When EGCG was added separately from TFdiG or TsA, the accumulation of EGCG in HT-29 cells was also significantly decreased regardless of when TFdiG or TsA was added during the uptake study (p<0.01). The results suggest that theaflavins and TsA may interrupt EGCG absorption through the gastrointestinal epithelium.

• Korean Journal of Pharmacognosy
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• v.34 no.3 s.134
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• pp.206-209
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• 2003

The fruit of Evodia officinalis (Rutaceae) is known for containing a number of indoloquinazoline and quinoline type alkaloids. Evodiamine, evocarpine and rutaecarpine are the major constituents of Evodiae Fructus. These alkaloids were isolated and determined by forming complex compounds from Evodiea Fructus. For the determination of these alkaloids, a new spectrophotometric method was developed with a simple and selective sample clean-up using thiocyanatocobaltate [II] complex ion. The absorbance of alkaloidal complex in 1.2-dichloroethane solution was measured at 625 nm. A calibration curve for the alkaloids isolated from Evodia Fruit was linear over the concentration range of $1.0{\sim}6.0\;mg/ml$. The method proved to be rapid, simple and reliable for the isolation and the determination of the alkaloids in Evodiae Fructus.

• Journal of Food Hygiene and Safety
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• v.27 no.4
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• pp.325-331
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• 2012

Food allergy refers to an immunologically mediated adverse reaction to food, mainly to proteinaceous constituents. Health implications vary between those individuals who experience mild physical discomforts to those with fast-acting, life-threatening anaphylactic reactions. The prevalence of food allergy is higher in children than in adults, estimated around 4-8% and 1-2% respectively in developed countries. Food allergy has no effective cure at the present time and total avoidance of causative foods is the most reliable prophylactic method currently recommended by the medical community. To help food allergic patients to make informed choices of their foods, mandatory labeling of selected food allergens has been introduced in several countries. All food allergen labelling provisions specify a set of allergens common to the regulated countries. Policy divergence, however, exists between countries by inclusion of additional allergens unique to specific countries and enforcement of specific labelling requirements. Such variations in food allergen labelling regulations make it difficult to manage allergen labeling in imported pre-packaged food products. This paper addresses two current issues in food allergen regulation: 1) an urgent need to determine true prevalence of food allergy in the Asia-Pacific region. This will enable refinement to the food allergen regulation to be more country-specific rather than simply adopting CODEX recommendations. 2) There is an urgent need for harmonization of food allergen regulation in order to prevent food allergen regulation becoming a trade barrier.

• Steel and Composite Structures
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• v.17 no.5
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• pp.753-776
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• 2014

In this paper, nonlinear vibration and post-buckling analysis of beams made of functionally graded materials (FGMs) resting on nonlinear elastic foundation subjected to thermo-mechanical loading are studied. The thermo-mechanical material properties of the beams are assumed to be graded in the thickness direction according to a simple power law distribution in terms of the volume fractions of the constituents, and to be temperature-dependent. The assumption of a small strain, moderate deformation is used. Based on Euler-Bernoulli beam theory and von-Karman geometric nonlinearity, the integral partial differential equation of motion is derived. Then this PDE problem which has quadratic and cubic nonlinearities is simplified into an ODE problem by using the Galerkin method. Finally, the governing equation is solved analytically using the variational iteration method (VIM). Some new results for the nonlinear natural frequencies and buckling load of the FG beams such as the influences of thermal effect, the effect of vibration amplitude, elastic coefficients of foundation, axial force, end supports and material inhomogenity are presented for future references. Results show that the thermal loading has a significant effect on the vibration and post-buckling response of FG beams.

• Journal of Korean Medical classics
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• v.34 no.4
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• pp.79-93
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• 2021

Objectives : This study analyzes the theoretical and clinical reasoning process of Zhao Xian-Ke that argued that the Mingmen is the true monarch of the body. Methods :The analysis focuses on how the arguments of Li Dong-yuan and Zhu Danxi was succeeded and supplemented by Zhao Xian-Ke into a new theoretical system in the Yiguan(醫貫). Results & Conclusions : Zhao's argument that the Mingmen is the true monarch of the body is a result of emphasis on the meaning of innate Qi that is separate from the Water and Fire of the Heart and Kidney, which is derived from the innate Qi concept of Li Dong-yuan's Spleen-Stomach Theory. Zhu Danxi's Ministerial Fire Theory was also accepted through the innate Qi concept of Ministerial Fire and True Yin, which contributed to the establishment of a systematical theory on Mingmen, Miniterial Fire, and True Yin as constituents of innate Qi. In conclusion, the Neijing's explanation that the Heart radiates Shenming as the monarch organ has been modified into innate Qi from the Mingmen reaching the Heart to radiate Shenming.

• Biomolecules & Therapeutics
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• v.29 no.2
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• pp.105-126
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• 2021

Traditional Chinese medicine (TCM) was the primary source of medical treatment for the people inhabiting East Asia for thousands of years. These ancient practices have incorporated a wide variety of materia medica including plants, animals and minerals. As modern sciences, including natural products chemistry, emerged, there became increasing efforts to explore the chemistry of this materia medica to find molecules responsible for their traditional use. Insects, including beetles have played an important role in TCM. In our survey of texts and review articles on TCM materia medica, we found 48 species of beetles from 34 genera in 14 different families that are used in TCM. This review covers the chemistry known from the beetles used in TCM, or in cases where a species used in these practices has not been chemically studied, we discuss the chemistry of closely related beetles. We also found several documented uses of beetles in Traditional Korean Medicine (TKM), and included them where appropriate. There are 129 chemical constituents of beetles discussed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.s01
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• pp.124-138
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• 1988

This paper comprised a review of published literature dealing with the evaluation of tobacco quality and usability. Evaluation of tobacco quality and usability seems to be difficult not only due to our inability to define them in simple and easily measurable term but also due to their relations to the profitability of tobacco companies and safety of comsumers. Chemical constituents and smoking taste and aroma of the tobacco represent the underlying basis for tobacco quality: however, tobacco is still purchased upon its physical appearance. Grade and value system is very convenient for evaluating the tobacco quality, if the system is based on the triangular relationship of physical appearance, chemical and smoking properties of tobacco, and also based on intrinsic quality of the tobacco independent of external influences. Grade and value system for tobacco in Korea is thought to be influenced by external factors besides intrinsic quality. Therefore, we have to concern new systems that could be supplement to, or replacement for currently available grade and value system.