• International Journal of Oral Biology
• /
• v.31 no.2
• /
• pp.53-65
• /
• 2006

Calcium concentration in the bone resorption lacunae is high and is in the mM concentration range. Both osteoblast and osteoclast have calcium sensing receptor in the cell surface, suggesting the regulatory role of high extracellular calcium in bone metabolism. In vitro, high extracellular calcium stimulated osteoclastogenesis in coculture of mouse osteoblasts and bone marrow cells. Therefore we examined the genes that were commonly regulated by both high extracellular calcium and $1,25(OH)_2vitaminD_3(VD3)$ by using mouse oligo 11 K gene chip. In the presence of 10 mM $[Ca^{2+}]e$ or 10 nM VD3, mouse calvarial osteoblasts and bone marrow cells were co-cultured for 4 days when tartrate resistant acid phosphatase-positive multinucleated cells start to appear. Of 11,000 genes examined, the genes commonly regulated both by high extracellular calcium and by VD3 were as follows; 1) the expression of genes which were osteoclast differentiation markers or were associated with osteoclastogenesis were up-regulated both by high extracellular calcium and by VD3; trap, mmp9, car2, ctsk, ckb, atp6b2, tm7sf4, rab7, 2) several chemokine and chemokine receptor genes such as sdf1, scya2, scyb5, scya6, scya8, scya9, and ccr1 were up-regulated both by high extracellular calcium and by VD3, 3) the genes such as mmp1b, mmp3 and c3 which possibly stimulate bone resorption by osteoclast, were commonly up-regulated, 4) the gene such as c1q and msr2 which were related with macrophage function, were commonly down-regulated, 5) the genes which possibly stimulate osteoblast differentiation and/or mineralization of extracellular matrix, were commonly down-regulated; slc8a1, admr, plod2, lox, fosb, 6) the genes which possibly suppress osteoblast differentiation and/or mineralization of extracellular matrix, were commonly up-regulated; s100a4, npr3, mme, 7) the genes such as calponin 1 and tgfbi which possibly suppress osteoblast differentiation and/or mineralization of extracellular matrix, were up-regulated by high extracellular calcium but were down-regulated by VD3. These results suggest that in coculture condition, both high extracellular calcium and VD3 commonly induce osteoclastogenesis but suppress osteoblast differentiation/mineralization by regulating the expression of related genes.

• Archives of Pharmacal Research
• /
• v.27 no.8
• /
• pp.840-844
• /
• 2004

A triterpene was isolated as a cytotoxic principle from the dichloromethane extract of Korean mistletoe (KM； Viscum album colora turn) by repeated silica gel chromatography and recrystalli-zation. In in vitro analysis of cytotoxic activity using various human and murine tumor cell lines, the dichloromethane extract of KM was highly cytotoxic against these cells. We isolated the most active compound, referred to VD-3, from the dichloromethane extract of KM. The VD-3 was shown to be less cytotoxic to normal cells (murine splenocytes). From the identification of the chemical structure of VD-3 by spectral data and chemical synthesis, the compound was proven to be epi-oleanolic acid. Tumor cells treated with VD-3 showed a typical pattern of apo-ptotic cell death, such as apparent morphological changes and DNA fragmentation. These results indicate that epi-oleanolic acid is an important compound responsible for antitumor activity of KM.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.25 no.9A
• /
• pp.1413-1421
• /
• 2000

In this paper, we analyze previous flow control algorithm for serving ABR traffic, and then propose the algorithm which calculate fair transmission rate and control efficiently ABR traffic using VS/VD switch which has an effect on WAN environment with long delay. For getting the transmission rate, the proposed algorithm use FMMAR as ER scheme which calculate exactly the fair share. And, in large delay state. we can obtain fair cell sharing by calculating transmission rates which obtained by transmitted queue length information of VD to VS for serve and drain cell in queue Through the computer simulation, we evaluate the performance of proposed algorithm. According to the results, the proposed algorithm shows good performance.

• YAKHAK HOEJI
• /
• v.41 no.2
• /
• pp.195-202
• /
• 1997

The purpose of this study was to determine pharmacokinetic parameters of vancomycin using two point calculation(TPC) and Bayesian methods in 16 Korean normal volunteers and 15 g astric cancer patients. Nonparametric expected maximum(NPEM) algorithm for calculation of population pharmacokinetic parameter was used, and these parameters were applied for clinical pharmacokinetic parameters by Bayesian analysis. Vancomycin was administered 1.0g every 12 hrs for 3 days by IV infusion over 60 minutes. The volume of distribution(Vd), elimination rate constant(Kel) and total body clearance(CLt) of vancomycin in normal volunteers using TPC method were $0.34{\pm}0.06 L/kg,\; 0.19{\pm}0.01 hr^{-1}$ and $4.08 {\pm} 0.93 L/hr$, respectively, The Vd, Kel and CLt of vancomycin in gastric cancer patients using TPC method were $0.46 {\pm} 0.06 L/kg, 0.17{\pm}0.02 hr^{-1}$ and $4.84 {\pm} 0.57 L/hr$ respectively. There were significant differences(p<0.05) in Vd. Kel and CLt between normal volunteers and gastric cancer patients. Polpulation pharmacokinetic parameter, the slope(KS) of the relationship beetween Kel versus creatinine Clearance, and the Vd were $0.00157{\pm}0.00029(hr{\cdot}mL/min/1.73m^2)^{-1},\; 0.631 {\pm} 0.0036 L/kg$ in gastric cancer patients using NPEM algorithm respectively. The Vd and Kel were $0.63{\pm}0.005 L/kg, 0.15 {\pm}0.027 hr^{-1}$ for gastric cancer patients using Bayesian method. There were significant differences(p<0.05) in vancomycin pharmacokinetics between Bayesian and TPC methods. It is considered that the population parameter in the patient population is necessary for effective Bayesian method in clinical pharmacy practise.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.37 no.1
• /
• pp.43-48
• /
• 2011

Introduction: This study examined the anatomical morphology of the medial surface of the posterior mandible using 3-dimensional cone-beam computed tomography (CT) images to reduce the number of complications related to dental implant placement. Materials and Methods: Fifty patients were enrolled in this study with an average age (${\pm}$standard deviation) of 44.28 (${\pm}13.05$). On the coronal views cone-beam CT of the first molars, the distance between the top of the canal and alveolar crest vertical distance (VD), the distance between the upper-most point of the canal and the point perpendicular to the lingual cortical margin of the mandible lingual distance (LD), the location of the starting point of VD for reducing from the vertical reference line (VD point), and the inclination of the mandibular medial surface (lingual inclination) were measured, and a statistical evaluation was performed using SPSS for Windows version 15.0. Results: The mean VD0 was $16.91{\pm}2.47\;mm$ and VDx decreased with increasing x value. The mean LD was $5.27{\pm}1.36\;mm$. The VD began to decrease at the mean location of $6.12{\pm}0.96\;mm$ from the vertical reference line. The mean lingual inclination was $1.52{\pm}0.72^{\circ}$. Conclusion: These results will assist in the accurate placement of dental implants and the reduction of complications, particularly in the case of preoperative implant planning using only 2-dimensional imaging methods. (ex. panoramic radiography)

• The Journal of the Acoustical Society of Korea
• /
• v.18 no.6
• /
• pp.65-70
• /
• 1999

In ATM network there exist several traffics according to QoS, such as CBR, rt-VBR, nrt-VBR, UBR, and ABR. Many studies have done at the traffic management of ABR which uses the unused network bandwidth. Many flow control mechanisms have proposed to use efficiently the unused bandwidth. In TMWG(Traffic Management Working Group) of ATM Forum, there exist rate-based, credit-based, and mixture of them to manage flow control of ABR traffic. Among these, rate-based mechanisms adopted as standard because it is flexible and also makes it possible to implement ATM switch with low price and high capacity. In this paper, we study the switch that uses EFCI, ER and VS/VD(Virtual Source/Virtual Destination) with rate-based mechanism. Instead of using queue threshold, we propose a new algorithm which uses bandwidth threshold of input stage of switch, and manages efficiently ABR traffic with EPRCA algorithm.

• Journal of the Korean Wood Science and Technology
• /
• v.40 no.1
• /
• pp.44-52
• /
• 2012

This study examined the effects of the drying rate, temperature distribution and vapor pressure on the surface checks occurring during the air circulating oven-drying of hollowed short Japanese larch (Larix Kaemferi C.) round posts treated with coating (CO) and vapor-dam (VD). The hollowed round posts could be dried from the green condition to a moisture content of approximately 8% in 72 to 144 hours. The temperature in the hole was higher than that inside of wood for Control and VD specimens, while VD specimen showed opposite distribution. The vapor pressure inside the wood was higher than that in the hole for the CO and VD specimens during hole drying stage. There were few surface checks found in the specimens but the number increased in order the of CO, VD and Control specimens.

• Journal of International Academy of Physical Therapy Research
• /
• v.10 no.2
• /
• pp.1768-1773
• /
• 2019

Background: Aging reduces cognitive abilities, including visual memory (VM) and visual discrimination (VD). Since common cortical networks subserve eye movement and attention, voluntary eye movement may improve visual attention. Visual selective attention was major role for memory, and visual memory and visual attention are intimately related. Objective: To identify the improvement in VD and VM, after implementing the eye movement program consisting of saccadic eye movement (SEM) and pursuit eye movement (PEM) in the institutionalized healthy elderly. Design: Randomized controlled trial. Methods: The study involved a sample of 36 participants, and the mean age was 79.03 years (range 76~84 years). They were randomly allocated to the experimental group (n=16) and control group (n=20). Participants in the experimental group performed SEM 5 times per week for 4 weeks: twice daily at the same time in the morning and afternoon. The program was carried out for 3 minutes, and it consisted of SEM and PEM. The target's moving frequency was set at 0.5 Hz. VM and VD at the baseline and post-intervention were measured using Motor-Free Visual Perception test-4 (MFVPT-4). Results: VM significantly improved in the experimental group (p < .01), and significant differences were observed compared to the control group (p < .01). There was no significant change in VD. Conclusion: The eye movement program consisting of SEM and PEM increased VM more than VD. Therefore, eye movement program was feasible interventions for improving VM in institutionalized elderly persons.

• Proceedings of the KIEE Conference
• /
• 2004.07c
• /
• pp.1793-1795
• /
• 2004

지금까지 변전소나 개폐소에서 전류, 전압을 계측하는 수단으로서 주로 철심과 권선으로 구성되어진 변류기(CT), 계기용 변압기(PT, PD)가 사용되어 왔다 최근, 2차측의 계측기나 보호 Relay의 Digital화가 진전되어, 또한 이것을 Digital Network으로 종합한 Intelligent 변전소의 구축이 검토되어짐에 따라 Digital Network에 대응한 신형 CT, VD가 요구되어 지고 있다. 상기와 같은 요구로 인해 당사에서는 CT는 검출부에 Rogowski Coil을 적용하며 그 후단에 적분기를 설치하였으면, VD는 검출부에 중간 전극을 이용해서 분압하는 방식인 Capacitive Voltage Divider를 사용하고 증폭기를 삽입하여, 각각 요구되는 전압 신호를 얻었다. 이러한 신형 CT/VD의 적용으로 종래의 CT/PT가 차지하는 공간이 필요 없게 되어 컴팩트한 GIS의 구조가 능하게 되어 있다.

• 한국HCI학회:학술대회논문집
• /
• 2006.02a
• /
• pp.608-612
• /
• 2006

3 차원 공간상에서의 상호작용이란 특정 공간내의 오브젝트를 그 위치와 좌표축에 따라 조작하는 행위를 말한다. 이러한 3 차원 공간상의 상호작용을 행할 때 발생하는 가장 큰 문제중의 하나는 사용자가 현재 조작하고 있는 커서 또는 포인터의 깊이적 위치를 알기 힘들다는 점이며 흔히 깊이 지각문제(Depth Perception Problem)으로 불리 운다. 본 논문은 깊이 지각문제를 발생시키는 기본적인 요소중의 하나를 가상환경을 표현하기 위해 인공적으로 생성된 조망 절두체라고 고려하고 이에 대해서 논의한다. 이를 위하여 3 차원 입력 장치(SensAble PHANToM(R) OmniTM)를 이용한 간단한 위치지정 작업을 다양한 FOV(Field of View)와 VD(Viewing Direction)의 환경에서 피실험자들에게 수행하게 하였다. 결과적으로, 작업환경내의 FOV 변화는 작업수행의 정확도에 영향을 끼쳤으며, VD 의 경우, 사용자가 실제로 작업환경을 보는 것과 유사한 VD 환경이 효율성의 측면에서 보다 더 높은 작업수행 결과를 보였다.