• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2017년도 춘계학술대회 논문집
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• pp.80-80
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• 2017

Titanium and its alloys that have a good biocompatibility, corrosion resistance, and mechanical properties such as hardness and wear resistance are widely used in dental and orthopedic implant applications. However, they do not form a chemical bond with bone tissue. Plasma electrolytic oxidation (PEO) that combines the high voltage spark and electro-chemical oxidation is a novel method to form ceramic coatings on light metals such as tita-nium and its alloys. This is an excellent re-producibility and economical, because the size and shape control of the nano-structure is relatively easy. Silicon (Si), manganese (Mn), and magne-sium (Mg) have a useful to bone. Particularly, Si has been found to be essential for normal bone, cartilage growth, and development. Mn influences regulation of bone remodeling be-cause its low content in body is connected with the rise of the concentration of calcium, phosphates and phosphatase out of cells. Pre-studies have shown that Mg plays very im-portant roles in essential for normal growth and metabolism of skeletal tissue in verte-brates and can be detected as minor constitu-ents in teeth and bone. In this study, Electrochemical behavior of plasma electrolytic oxidized films formed in solution containing Mn, Mg and Si ions were researched using various experimental in-struments. A series of Si-Mn-Mg coatings are produced on Ti dental implant using PEO, with the substitution degree, respectively, at 5 and 10%. The potentiodynamic polarization and AC impedance tests for corrosion behav-iors were carried out in 0.9% NaCl solution at similar body temperature using a potentiostat with a scan rate of 1.67mV/s and potential range from -1500mV to + 2000mV. Also, AC impedance was performed at frequencies anging from 10MHz to 100kHz for corrosion resistance.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권4호
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• pp.1368-1389
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• 2014

Three-dimensional multiple-input multiple-output (3D MIMO) and large-scale MIMO are two promising technologies for upcoming high data rate wireless communications, since the inter-user interference can be reduced by exploiting antenna vertical gain and degree of freedom, respectively. In this paper, we derive the achievable sum rate of 3D MIMO systems employing zero-forcing (ZF) receivers, accounting for log-normal shadowing fading, path-loss and antenna gain. In particular, we consider the prevalent log-normal model and propose a novel closed-form lower bound on the achievable sum rate exploiting elevation features. Using the lower bound as a starting point, we pursue the "large-system" analysis and derive a closed-form expression when the number of antennas grows large for fixed average transmit power and fixed total transmit power schemes. We further model a high-building with several floors. Due to the floor height, different floors correspond to different elevation angles. Therefore, the asymptotic achievable sum rate performances for each floor and the whole building considering the elevation features are analyzed and the effects of tilt angle and user distribution for both horizontal and vertical dimensions are discussed. Finally, the relationship between the achievable sum rate and the number of users is investigated and the optimal number of users to maximize the sum rate performance is determined.

• Applied Microscopy
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• 제2권1호
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• pp.17-31
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• 1972

우기자혹응애 (Eriophyes kuko KISHIDA)의 기생에 의하여 구기자 나무 (Lycium Chinens MILL) 잎에 형성되는 흑 (mite gall) 의 행태적 변화를 광학현미경 및 전자현미경으로 관찰한 결과는 다음과 같다. 1. 광현적 관찰 : 구기자혹응애가 구기자나무의 어린잎의 뒷면 표피세포에 침입되면 먼지 표피세포가 이상비대를 하면서 혹이 형성되기 시작한다. 혹이 성장함에 따라 붕상조직과 해면상조직의 세포도 이상비대를 하게되고, 점차적으로 각 조직의 세포는 이상비대로 인한 불규칙한 형태적 변화를 일으켜 조직의 구별이 힘들게 된다. 이상비대한 혹세포의 핵은 건전세포의 핵보다 크며, 혹이 성장함에 따라서 핵의 크기도 커진다. 2. 전현적 관찰 : 혹이 성장함에 따라 혹세포의 mitochondria, golgi-apparatus. plastid 등은 퇴 화 및 붕괴되고, 특히 큰 흑의 이상비대한 혹세포에는 성상체 (star body) 와 환상 (ring form) 의 구조등이 나타난다.

• 대한소아치과학회지
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• 제24권4호
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• pp.795-804
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• 1997

Developmental dental morphological anomalies are fusion, gemination, twinning, concrescence and etc. They may cause many problems in conservative, periodontal and esthetic aspects. Fusion is a condition where two separate tooth buds unite at some stage in their development to form a bifid crown. If tooth contact occurs early, at least before the start of calcification, the two teeth may be completely unites to form a single large tooth. If tooth contact occurs after the time when a portion of the tooth crown has completed its formation, there may be union of the roots only. In fusion the dentin is always confluent. Fusion teeth is more common in the deciduous than in the permanent dentition. Fused teeth are relatively rare, and are mostly mandibular anterior teeth. Fusion of normal and supernumerary teeth or between normal teeth may occurs. The exact etiology factor of fusion is unknown, but genetic and environmental factors seems to be related. A variety of complications and subsequent treatments have been suggested on this teeth. Periodontal conditions may arise due to a groove formed at the line of fusion of the two teeth. Crowding or Protrusion with potential for malocclusion or delayed eruption of adjacent teeth. Fusion teeth appear in the anterior region, they usually cause esthetic problems. Treatments vary depending on the problem, the location, and the extent of fusion. Treatment of fused teeth has been reported from endodontic, orthodontic, periodontic, surgical and multidisciplinary. This report presents the esthetic improvements by separation of two clinical crowns. Bone reduction or endodontic treatments are not required.

• Journal of Ginseng Research
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• 제45권2호
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• pp.228-235
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• 2021

Backgroud: Ginsenoside compound K (GK) is a major metabolite of protopanaxadiol-type ginsenosides and has remarkable anticancer activities in vitro and in vivo. This work used an ionic cross-linking method to entrap GK within O-carboxymethyl chitosan (OCMC) nanoparticles (Nps) to form GK-loaded OCMC Nps (GK-OCMC Nps), which enhance the aqueous solubility and stability of GK. Methods: The GK-OCMC Nps were characterized using several physicochemical techniques, including x-ray diffraction, transmission electron microscopy, zeta potential analysis, and particle size analysis via dynamic light scattering. GK was released from GK-OCMC Nps and was conducted using the dialysis bag diffusion method. The effects of GK and GK-OCMC Nps on PC3 cell viability were measured by using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. Fluorescent technology based on Cy5.5-labeled probes was used to explore the cellular uptake of GK-OCMC Nps. Results: The GK-OCMC NPs had a suitable particle size and zeta potential; they were spherical with good dispersion. In vitro drug release from GK-OCMC NPs was pH dependent. Moreover, the in vitro cytotoxicity study and cellular uptake assays indicated that the GK-OCMC Nps significantly enhanced the cytotoxicity and cellular uptake of GK toward the PC3 cells. GK-OCMC Nps also significantly promoted the activities of both caspase-3 and caspase-9. Conclusion: GK-OCMC Nps are potential nanocarriers for delivering hydrophobic drugs, thereby enhancing water solubility and permeability and improving the antiproliferative effects of GK.

• Journal of Community Nutrition
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• 제1권1호
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• pp.52-59
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• 1999

The present study was conducted to evaluate the dietary fiber intake of 130 subjects, that included 49 subjects(29 form Wonju, 20 from Kangnung) with diabetes mellitus, 23 hyperlipidemia patients, and 58 normal subjects. After the type and amount of foods that a subject took for one day were investigated using the 24-h recall method, the intake of various nutrients and dietary fiber were calculated using a program that already contained the information on dietary fiber contents. The results showed that diabetics from Kangnung who did not undergo dietary therapy had more fat intake that those from Wonju, hyperlipidemia patients, and normal subjects thus, had more energy intake. Also, the crude fiber intake in male and female diabetics from Kangnung were 8.43${\pm}$3.47g and 3.35${\pm}$3.29g, respectively, showing significantly high amounts compared to those of male and female diabetics from Wonju, hyperlipidemia patients, and normal subjects; however, the intake of crude fiber per 1,000 kcal in males and females was not significantly different among the four groups. Also, the dietary fiber intake(14.8-19.8g/day) and the dietary fiber intake per energy unit(7.7-10.9g/1,000kcal) were not significantly different between the four groups. The dietary fiber intakes of diabetics and hyperlipidemia patients were not significantly different from those in normal subjects, and these amounts were significantly lower than recommended levels. Thus, the methods of increasing dietary fiber intake, such as developing low-calorie, high-dietary fiber foods or additives, needs to be researched.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제1권1호
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• pp.40-54
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• 1990

Rutter의 아동행동평가표에 의한 정서행동문제아동들과 정상아동들 리고 DSM-III-R의 진단기준에 부합되는 주의력결핍과잉운동장애아동들에 대해 뇌파조사를 시행하여 뇌파이상의 빈도와 양상을 알아보았다. 그 결과, 정서행동문제아동군은 정상대조군과 뇌파이상의 빈도 및 양상에 차이를 보이지 않았지만. 주의력결핍과잉운동장애아동군은 정상대조군에 비해 후두부에서 alpha파의 평균 진폭이 낮았고, 평균출현시간이 짧았으며, 또한 좌측 후두부가 우측 후두부에 비해 alpha파 특히 alpha(2)과의 평균출현시간이 길었다. 이로써 국민학교아동의 정서행동문제는 뇌파이상과는 별 관련성이 없는 것으로 판단된다. 하지만 주의력결핍과잉운동장애아동군은 정상 대조군에 비해 alpha파의 발달이 덜 되어 있음을 알았다.

• 대한의생명과학회지
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• 제8권2호
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• pp.71-75
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• 2002

Paraquat (N,N'-dimethyl-4,4'-bipyrrimidinium-dichlorides (PQ): MW 186.6) has been used to killing verierty of hubside plants. For this study were use Sprague-dawely rats (190$\pm$10 gm) and injection 40 mg/kg BW of paraquat (LD$_{50}$) to 24 hrs PQ and 4 days PQ group excepte normal control. For the measurement of blood calcium Ino-phosphorus and activity of alkaline phosphatase (ALP) by HITTACH 746. In serum phosphoruse of normal control were 8.0$\pm$1.2 mg/dl and 24 hrs PQ group were 8.9$\pm$1.0 mg/dl (P<0.05) and 4 days PQ group were 8.8$\pm$0.42 gmm/dl (P<0.05). In serum phosphorus were very sensitive uptaked to 10% within only 24 hours, but 4 days of PQ were similar uptake level than 24 hrs PQ. So this 8.9 mg/dl of sem phosphorus may be thought threshold level becouse does not more encrease. In blood calcium normal of rats were measured 9.51$\pm$0.3 mg/dl and 24 hrs of PQ group were 9.9$\pm$0.51 mg/dl (uptaked 4.5%, p>0.05). This uptake cannot fined meaning mathmatic statistics but 4 days PQ groups of calcium were 10.43$\pm$0.37 gm/dl (uptaked 10%, p<0.05). That 24 hrs PQ groups of caclium dose not reacted sensitive to irritated by PQ. So, when use oxidants of PQ, the blood calcium and Ino-phosphorus were linear correlated uptake that reasone thought may be move out form hardness bone tissue to in blood it does not take feeding to hunger for 4 days. In ALP normal of rats were measured 991$\pm$106 unit/L. In 24 hrs irritated PQ rats were fall down by 629$\pm$91 unit/L (P<0.001) but in 4 days of PQ rats were 792$\pm$85 unit/L (P<0.0011) that the activity of level were mild recovered activity from 629 unit (63%) to 792 unit (80%). So, that the reasone of ALP were very sensitive activity and reverse correlated to blood calcium or phosphorus irritated by PQ.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제7권2호
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• pp.179-189
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• 1996

주의력결핍 ${\cdot}$ 과잉운동장애 아동의 주의력결핍 양상을 발견하고자 뇌사건관련전위(ERP)를 측정하고, 연령을 맞춘 정상대조군과 비교하여 다음과 같은 결과를 얻었다. 1) 9세 이후의 주의력결핍 ${\cdot}$ 과잉운동장애 환아군은 동일한 연령군의 정상아동보다 선택적 주의집중력 및 자극변별력을 시사하는 파형의 잠복기(N1, P2)가 과제와 연관된 자극에 대해서 정상아동보다 통계적으로 유의하게 지연되어 있었다. 2) 환아군은 과제와 무관한 자극에 대해서는 정상아동보다 주의력을 시사하는 파형의 잠복기가 단축되고 진폭이 증가되어 있었다. 이를 통해 주의력결핍 ${\cdot}$ 과잉운동장애 환아군은 정상아동보다 쉽게 산만해지며 과제와 무관한 자극에 주의를 기울이는 반면, 과제를 수행하는 선택적이고 지속적인 주의집중력은 정상아동보다 떨어진다는 결론을 얻었다.

• Clinical and Experimental Reproductive Medicine
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• 제30권2호
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• pp.179-184
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• 2003

The Mayer-Rokitansky-Kuster-Hauser (MRKH) syndrome refers to a condition which presents as normal female secondary sex characteristics, normal external genitalia, congenital absence of the internal vagina, usually a rudimentary uterus in the form of bilateral noncanaliculated muscular buds, and normal tubes and ovaries with normal cytogenetic and endocrine evaluation, frequent association of renal, skeletal and other congenital anomalies. However, rarely, whole uterus or a segment of uterus may be present, but lacking a conduit to the introitus. If a partial endometial cavity is present in a segment of uterus, cyclic abdominal pain may be a complaint and furthermore endometiosis can be developed. Recently, we experienced a case of MRKH syndrome with the segments of uterus accompanying endometriosis in young woman. We present this case with a brief review of literatures.