A Pilot Study for Developing an Assessment Scale for the Effect of Herbal Medicine in Healthy Children: Open-Label Study with Gami-Jiwhangtang

Bahn Geon-Ho,Kim Chang-Ju,Chung Joo-Ho,Kim Yong-Hee,Paik Eun-Kyung,Park Jae-Hyung The Society of Korean Medicine 2004 대한한의학회지 Vol.25 No.4

Objective : While the demand for herbal medicine has increased continuously, scientific data attesting to pharmacological activity are still insufficient. One important reason, especially in child patients, is the shortage of standardized instruments for clinical research. This study was designed to develop a scale to assess the effect of herbal medicine in children. Methods : The authors chose Gami-jiwhangtang (GJT) as a standard formulation and developed a scale, Bahn's Drug Evaluation Scale (BaDES), for this experiment. Forty-two healthy children, 7 and 8 years old, living in Seoul, Korea, volunteered to use GJT. The experimental group received GJT for 6 weeks, whereas the control group received no medicine. The children's mothers in both groups completed the BaDES on the sixth and twelfth week after GJT was commenced. Results : The experimental group showed a significant improvement in overall physical condition and gastrointestinal function as compared with the control group. Conclusion : These results suggest that BaDES may be a useful assessment tool for measuring the effect of herbal medicine.

Development of a Water-Window X-ray Source Using a Liquid-Nitrogen Jet

B. Ahn,J. Kim,J. Son,B. Kim,D. Kim 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.54 No.1

As a source for a soft X-ray microscope, a liquid-nitrogen jet has been developed and its radiation characteristics have been investigated for various laser parameters, such as the laser pulse energy and duration. The effects of pre-pulse and multiple pulses have also been stud- ied. The focus has been the N VI 1s2-1s2p transition at 2.88 nm. The investigation shows that the laser intensity for the maximum conversion efficiency scales as Im ∝ 1/T^∝, where ∝ = 0.9 ± 0.15. The study of the pre-pulse effect on the conversion effciency shows that a pre-pulse of only 2 mJ enhances the conversion efficiency by 10 - 15 times for the main pulse of 15 - 60 mJ at a delay of 3 - 6 ns. The photon flux is 1.2 × 10^12 photons / (pulse sr) at a delay of 4 ns for a main pulse of 60 mJ with a pre-pulse of 4 - 8 mJ. The study of the multiple pulse effect was done in the 4-pulse configuration. The enhancement of the radiation compared to the accumulation of the radiation intensity of each pulse was observed at a certain delays between 4 pulses, implying that there exists a proper pulse structure for maximum radiation. As a source for a soft X-ray microscope, a liquid-nitrogen jet has been developed and its radiation characteristics have been investigated for various laser parameters, such as the laser pulse energy and duration. The effects of pre-pulse and multiple pulses have also been stud- ied. The focus has been the N VI 1s2-1s2p transition at 2.88 nm. The investigation shows that the laser intensity for the maximum conversion efficiency scales as Im ∝ 1/T^∝, where ∝ = 0.9 ± 0.15. The study of the pre-pulse effect on the conversion effciency shows that a pre-pulse of only 2 mJ enhances the conversion efficiency by 10 - 15 times for the main pulse of 15 - 60 mJ at a delay of 3 - 6 ns. The photon flux is 1.2 × 10^12 photons / (pulse sr) at a delay of 4 ns for a main pulse of 60 mJ with a pre-pulse of 4 - 8 mJ. The study of the multiple pulse effect was done in the 4-pulse configuration. The enhancement of the radiation compared to the accumulation of the radiation intensity of each pulse was observed at a certain delays between 4 pulses, implying that there exists a proper pulse structure for maximum radiation.

NOVEL ANTICARCINOGENIC COMPOUNDS ISOLATED FROM ARTEMISIA CAPILLARIS

Bahn, Kyeong N.,Lee, Eun J.,Lee, Jung M.,Byun, Jae I.,Park, Sook J.,Yang, Min S.,Ha, Yeong L. Plant Molecular Biology & Biotechnology Research C 1994 Plant molecular biology and biotechnology research Vol.1994 No.

Chloroform fraction of hot-methanol soluble materials from Artemisia capaillaris, which inhibited DMBA-induced mouse skin carcinogenesis (Bahn et al., 1993), was further fractionated into F1 fraction by combination of solvent partition and TLC procedures. From the F1 fraction exhibited a strong cytotoxicity (ED_(50):<0.08vg/ml) for both L1210 and S- 180 mouse cancer cells, achillin and its isomer were identified as the major anticarcinogenic compounds.

Characterization of Water-Filled Ag/AgCl Reference Electrode

Bahn Chi Bum,Oh Sihyoung,Hwang Il Soon,Chung Hahn Sup,Jegarl Sung The Korean Electrochemical Society 2001 한국전기화학회지 Vol.4 No.3

외부 Ag/AgCl 기준 전극은 가압형 및 비등형 경수로 환경에 널리 사용되었다. 전극의 채움 용액 (Siting solution)으로 통상 KCl을 사용하는데, 다공성 지르코니아로 만들어지는 플러그를 통한 Cl 이온의 누설이 전극의 전위차 변동을 유발하는 문제가 있다. 누설로 인한 전위차 변동의 문제를 해결하기 위해 채움 용액으로 순수를 사용하였다 순수를 사용하는 경우 상온에서의 AgCl용해도에 의해 Cl이온의 농도가 결정된다. 붕산과 수산화리튬 혼합용액으로 $288^{\circ}C$에서 전극의 안정성 실험을 실시하였다. 약 일주일간 전위차 변화는 10mV 이내였으며, $288^{\circ}C$와 $240^{\circ}C$에서의 온도 사이클링 시험 전후의 전위차 변화는 15mV 이내였다. 이온의 limiting equivalent conductances와 Agar의 수역학적 이론을 토대로 하여 전극의 TLJP을 계산하였다. 전극 채움 용액 내의 Cl이온 농도를 상온에서 측정한 값으로 보정하여 이론값을 계산할 경우, 실험값과 비교적 잘 일치하는 것을 알 수 있었다. Pressure-balanced external Ag/AgCl electrode has been extensively used for both Pressurized Water Reactor (PWR) and Boiling Water Reactor (PWR) environments. The use of KCI-based buffer solution often becomes the source of electrode potential drift due to slow leakage through its porous plug, typically made of zirconia. It is reported that results of our effort to improve the stability of electrode potential by using high purity water as the filling solution in which $Cl^-$ ion activity can be established and maintained at the solubility of AgCl even with the sustained leakage for a long period. Stability tests have been made in boron and lithium mixture solution at $288^{\circ}C$. The electrode potential remained stable within 10 mV over one week period. And after a thermal cycle between 288 to $240^{\circ}C$ the potential shift of Ag/AgCl electrodes did not exceed 15 mV By using the limiting equivalent ionic conductances and Agar's hydrodynamic theory, the thermal liquid junction potential (TLJP) of the electrode has been predicted. The calculated values for the water-fiued Ag/AgCl electrode potential, in which the chlorine concentration in the filling solution was derived from the measured data at ambient temperature, had a good agreement with the experimental values.

Characterization Studies on Data Access Bias in Mobile Platforms

Bahn, Hyokyung The Institute of Internet 2021 International journal of advanced smart convergenc Vol.10 No.4

Data access bias can be observed in various types of computing systems. In this paper, we characterize the data access bias in modern mobile computing platforms. In particular, we focus on the access bias of data observed at three different subsystems based on our experiences. First, we show the access bias of file data in mobile platforms. Second, we show the access bias of memory data in mobile platforms. Third, we show the access bias of web data and web servers. We expect that the characterization study in this paper will be helpful in the efficient management of mobile computing systems.

Analyzing Input Patterns of Smartphone Applications in Touch Interfaces

Bahn, Hyokyung,Kim, Jisun The Institute of Internet 2021 International journal of advanced smart convergenc Vol.10 No.4

Touch sensor interface has become the most useful input device in a smartphone. Unlike keypad/keyboard interfaces used in electronic dictionaries and feature phones, smartphone's touch interfaces allow for the recognition of various gestures that represent distinct features of each application's input. In this paper, we analyze application-specific input patterns that appear in smartphone's touch interfaces. Specifically, we capture touch input patterns from various Android applications, and analyze them. Based on this analysis, we observe a certain unique characteristics of application's touch input patterns. This can be utilized in various useful areas like user authentications, prevention of executing application by illegal users, or digital forensic based on logged touch patterns.

Nucleoredoxin promotes adipogenic differentiation through regulation of Wnt/관-catenin signaling.

Bahn, Young Jae,Lee, Kwang-Pyo,Lee, Seung-Min,Choi, Jeong Yi,Seo, Yeon-Soo,Kwon, Ki-Sun American Society for Biochemistry and Molecular Bi 2015 Journal of lipid research Vol.56 No.2

<P>Nucleoredoxin (NRX) is a member of the thioredoxin family of proteins that controls redox homeostasis in cell. Redox homeostasis is a well-known regulator of cell differentiation into various tissue types. We found that NRX expression levels were higher in white adipose tissue of obese ob/ob mice and increased in the early adipogenic stage of 3T3-L1 preadipocyte differentiation. Knockdown of NRX decreased differentiation of 3T3-L1 cells, whereas overexpression increased differentiation. Adipose tissue-specific NRX transgenic mice showed increases in adipocyte size as well as number compared with WT mice. We further confirmed that the Wingless/int-1 class (Wnt)/관-catenin pathway was also involved in NRX-promoted adipogenesis, consistent with a previous report showing NRX regulation of this pathway. Genes involved in lipid metabolism were downregulated, whereas inflammatory genes, including those encoding macrophage markers, were significantly upregulated, likely contributing to the obesity in Adipo-NRX mice. Our results therefore suggest that NRX acts as a novel proadipogenic factor and controls obesity in vivo.</P>

Crack growth of throughwall flaw in Alloy 600 tube during leak testing

Bahn, C.B.,Majumdar, S. North-Holland Pub. Co 2015 Nuclear engineering and design Vol.284 No.-

We examined the issue of whether crack growth in a full thickness material can occur in a leaking crack. A series of leak tests was conducted at a room temperature and constant pressure (17.3MPa) with Alloy 600 tube specimens containing a tight rectangular throughwall axial fatigue crack. To exclude a potential pulsation effect by a high pressure pump, the test water was pressurized by using high pressure nitrogen gas. Fractography showed that crack growth in the full thickness material can occur in the leaking crack by two mechanisms: time-dependent plasticity at the crack tip and fatigue induced by jet/structure interaction. The threshold leak rate at which the jet/structure interaction was triggered was between 1.3 and 3.3L/min for the specific heat of the Alloy 600 tube tested.

ISOPERIMETRIC INEQUALITIES FOR SECTORS ON THE MINKOWSKI 2-SPACETIME

Bahn, Hyoungsick,Hong, Sungpyo 경북대학교 위상수학 기하학연구센터 1999 硏究論文集 Vol.8 No.-

In the Minkowski 2-spacetime L^(2) the hyperbolic angle is defined by the hyperbolic parametrization of the plane. With this notion of hyperbolic angle Helzer obtained a relativistic version of Gauss-Bonnet formula (cf. [3]). In this paper, we derive an isoperimetric inequality for timelike sectors in L^(2) bounded by an achronal spacelike curve and two timelike rays from a point using this Gauss-Bonnet formula.

Application-Adaptive Performance Improvement in Mobile Systems by Using Persistent Memory

Bahn, Hyokyung The Institute of Internet 2019 Journal of Advanced Smart Convergence Vol.8 No.1

In this article, we present a performance enhancement scheme for mobile applications by adopting persistent memory. The proposed scheme supports the deadline guarantee of real-time applications like a video player, and also provides reasonable performances for non-real-time applications. To do so, we analyze the program execution path of mobile software platforms and find two sources of unpredictable time delays that make the deadline-guarantee of real-time applications difficult. The first is the irregular activation of garbage collection in flash storage and the second is the blocking and time-slice based scheduling used in mobile platforms. We resolve these two issues by adopting high performance persistent memory as the storage of real-time applications. By maintaining real-time applications and their data in persistent memory, I/O latency can become predictable because persistent memory does not need garbage collection. Also, we present a new scheduler that exclusively allocates a processor core to a real-time application. Although processor cycles can be wasted while a real-time application performs I/O, we depict that the processor utilization is not degraded significantly due to the acceleration of I/O by adopting persistent memory. Simulation experiments show that the proposed scheme improves the deadline misses of real-time applications by 90% in comparison with the legacy I/O scheme used in mobile systems.