Stereological Analysis on Migration of Human Neural Stem Cells in the Brain of Rats Bearing Glioma

Kim, Jae-Ho,Lee, Jong-Eun,Kim, Seung U.,Cho, Kyung-Gi Oxford University Press 2010 Neurosurgery Vol.66 No.2

<P>OBJECTIVE: The objective of this study was to determine the rate and pattern of NSC migration in the brain and its time course after NSC transplantation. METHODS: We investigated the tropism of HB1.F3 (F3) immortalized human NSCs in rats bearing U373 human glioma in the brain. Rats received an injection of human U373MG malignant glioma cells into the striatum followed by an injection of F3 cells into the contralateral hemisphere 7 days later. We analyzed the numbers, distribution, and migration rate of NSCs using unbiased stereology. RESULTS: Approximately 10% of the injected NSCs migrated into the tumor region by 50 minutes after NSC injection. The number of NSCs in the tumor region increased slowly up to 5 days post-injection and increased significantly up to 15 days post-injection. Changes in tumor volume showed similar patterns. The rate of NSC migration was approximately 175 microm/min. NSCs increased in number approximately 1.7-fold during day 1 in the absence of tumor cell inoculation in vivo. However, the proliferation of NSCs began to decline after 5 days after injection. CONCLUSION: We identified for the first time the rate and pattern of NSC migration to the tumor mass in vivo. These findings may provide useful information with respect to preclinical research of gene therapy for malignant gliomas.</P>

高等學校 數學科 敎育課程 改善의 方向

林在圭,奇宇恒 경북대학교 교육대학원 1974 논문집 Vol.5 No.-

In this paper, we investigate the organizations, objects and contents of mathematics among the gists of learning guidance in Japanese high school revised in October 1970. We compare and analyse it with the following subjects about organizations and contents of guidance in subject: ⑴ The previous curriculum of mathematics in Japanese high school. ⑵ The contents of guidance in the text S.M.S.G. ⑶ The contents of guidance in the text U.I.C.S.M. ⑷ The curriculum of Mathematics in Korean high school. Comparing the differences between the present contents and methods of the revised curriculum of mathematics in Japan and those of the previous one, and analizing research results of U.S.A., we obtain reference materials for revision of curriculum of our country.

Relativistic Analogue Hidden in Projectile Motion

Lim Jae Hoon,Jung Dong-Won,Kim U-Rae,Cho Sungwoong,Lee Jungil 한국물리학회 2020 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.77 No.8

We present a four-vector analogue Uμ≡U0,U)=(|V'|,V) that can be directly constructed from the velocity of a projectile. Here, V and V' are the velocities of a projectile at heights h+H and h, respectively. In the non-relativistic regime, the mathematical structure of this four-vector analogue has an exact correspondence to the relativistic counterpart four-velocity uμ=γ(1,β)c of a massive particle. Based on this observation, we illustrate the design of an introductory laboratory experiment to investigate the Lorentz invariance and its covariant nature by measuring the velocity of a projectile. The experiment may help students to acquire a concrete perspective of Lorentz covariance through their own measurements and analyses of a free-fall motion.

전열관의 굽힘 및 확관접합 잔류응력

장진성,배강국,김우곤,김선재,국일현,김성청,Jang, Jin-Seong,Bae, Gang-Guk,Kim, U-Gon,Kim, Seon-Jae,Guk, Il-Hyeon,Kim, Seong-Cheong 대한기계학회 2000 大韓機械學會論文集A Vol.24 No.2

Residual stress induced in U-bending and tube-to-tubesheet joint processes of PWR's row-1 heat exchanger tube was measured by X-ray method and Hole-Drilling Method(HDM). Compressive residual stresses(-) at the extrados surface were induced in U-bending, and its maximum value reached -319 MPa in axial direction at the position of $\psi$ = $0^{\circ}$. Tensile residual stresses(+) of $\sigma_{zz}$ = 45 MPa and $\sigma_{\theta\theta}$ = 25 MPa were introduced in the intrados surface at the position of $\psi$ = $0^{\circ}$. Maximum tensile residual stress of 170 MPa was measured at the flank side at the position of $\psi$ = $90^{\circ}$, i.e., at apex region. It was observed that higher stress gradient was generated at the irregular transition regions (ITR). The trend of residual stress induced by U bending process of the tubes was found to be related with the change of ovality. The residual stress induced by the explosive joint method was found to be lower than that by the mechanical roll method. The gradient of residual stress along the expanded tube was highest at the transition region (TR), and the residual stress in circumferential direction was found to be higher than the residual stress in axial direction.

방향성 연속주조된 Al-Cu합금의 연화처리에 따른 미세조직과 기계적 성질의 변화

제창웅,윤재홍,정동석 國立 昌原大學校 産業技術硏究所 1997 産技硏論文集 Vol.11 No.-

Directionally continuous casted Al-Cu alloys used the components of electronic and electric equipment need to specify the properties of them and optimum drawing condition in order to manufacture a fine wire. Therefore, the present investigation has been carried out for clarifying the changes of macrostructure, microstructure, mechanical properties, and the interrelations of them during annealing heat treatment in order to manufacture a fine wire in directionally continuous casted Al-Cu alloys. Recrystalized grains were not observed at below 200˚C in Al-1%Cu and Al-28%Cu alloys annealed, however recrystalized grains were observed with increasing annealing temperature. Recrystalization was occurred at inclusion/matrix interfaces and also appeared at the inclusions of smaller radius with increasing reduction ratio.

行列多項式 LYAPUNOV 函數 構成에 依한 誘導電動機의 安定度 解析

禹靖仁,李浚柝,文在星 동아대학교 공과대학 부설 한국자원개발연구소 1988 硏究報告 Vol.12 No.2

In this paper, when the steady state values for Multidimensional and Nonlinear Dynamic Models of Space Representations are given, Lyapunov functions of scalar types using matrix quadratic polynomials are constructed by Special Matrix Transformation Techniques and applied to Stability Analysis of Induction Motors. Futhermore, Lyapunov function construction procedures for linear systems can be specified in detail. But, unfortunately, for nonlinear systems, there are no the complete construction techniques. Therefore, in this paper, differently from conventional methods using Linearization obtained from Taylor series expansions about steady state operating points, linear terms and nonlinear ones are invidually separated, and by special matrix transformation techniques, similar Lyapunov function construction procedures such as in the cases of linear systems, are introduced, and are applied to Stability Analysis of induction motor. The hyperspaces of multidimensional stability region, obtained from these techniques, were larger than the obtained ones from conventional linearlization techniques about equilibrium points and were assured to be Lyapunov Asymptotic Stability Region ensuring the stable operation of induction motor.

오이의 品種 및 臺木의 種類에 따른 溢泌量, 無機成分 및 植物호르몬의 含量

鄭淳宰,申允燮,具禹書 東亞大學校生命資源科學大學附設 農業資源硏究所 1992 農業生命資援硏究 Vol.1 No.1

臺木의 種類 및 오이品種의 溢泌現象 및 無機成分과 식물 hormone 含量에 關하여 硏究하엿던 바 그 主要結果는 다음과 같이 要約될 수 있다. 1. 溢泌液의 量 및 經時的인 變化를 보면 接木오이가 自根오이보다 顯著히 높아 臺木의 效果가 뚜렷하였으며 自根苗에서는 四葉오이가, 接木苗에서는 四葉오이를 黑種호박에 接木한 苗에서 增加되었다. 經時的인 變化는 接木, 自根 共히 最初의 1時間 採取時에 가장 많았고 時間이 經過함에 따라 低下하였다. 2 .溢泌液內의 無機物含量은 수세미와 黑種호박에서 K, Ca, Mg含量이 높았고 만춘청장마디오이와 四葉오이는 接木에 依해 K와 Ca의 含量이 增加되었으나, 溢泌液內의 無機物의 含量과 臺木의 生育促進效果와는 特定한 關係가 있다고는 判斷되지 않는다. 3. 溢泌液으로부터 Cytokinine과 Gibberellin을 抽出할 수 있었는데 Bioassays에 依해 檢出된 Gibberellin含量은 臺木의 接穗促進效果와도 關係가 있을 것으로 推定되었으나 Cytokinine含量에서는 特定한 傾向을 찾아볼 수 없었다 Studies were conducted to investigate the xylem sap exudation phenomena, mineral element contents and endogenous plant hormones in cucumber cultivars and different rootstocks. The major results can be summarized as follows. 1. The amount of xylem sap exudated from the basal cut stem were significantly influenced by cucumber cultivars and kind of rootstock. Among the tested cucumber cultivars, ‘Sayeup’ showed the largest amount of xylem sap. ‘Heukzong’ rootstock also showed the largest amount of xylem sap among the tested rootstocks. The amount of xylem sap exudation was largest in the first hour of cut and gradually decreased with time after cutting. 2. The contents of K, Ca and Mg were higher in the xylem sap of ‘Susemi’ and ‘Heukzong’ rootstocks contents of K and Ca in ‘Manchoon Chungjang-madi’ and ‘Sayeup’ Cucumber were also increased by grafting. The contents of mineral elements in xylem sap of rootstocks could not be correlated with the growth promotion effect of the rootstocks. 3. Contents of gibberellin-like substance in xylem sap of rootstocks seemed to have some relationship on its growth promotive effect of the scion by rootstocks. Cytokinins were also extracted but their role in scion growth is yet to be clarified.

子宮內膜搔爬術 21例의 鍼麻醉效果에 대한 臨床的 硏究

金在圭,金相佑,李宜暻,金建植,金相佑,南相永 경희대학교 1997 慶熙醫學 Vol.13 No.1

복숭아 당도 표시 소포장 판매 사례 분석

이기우,최충돈,조재욱,김충실 한국식품유통학회 2004 食品流通硏究 Vol.21 No.3

This study was carried out to give reference data for peach producers who will be to determine an intention whether or not to select by brix degree and to sell by small package(about 2 kilograms). We developed 2 kilograms?package box. and selled peach indicated in brix degree, then analyzed the effect and consumers'preference degree for the sale. It was confirmed that peach package standard with indicating brix degree by consumers' preference was 2kg as the result of this study. 65% of consumers were satisfied 2kg package box. 18% of them replied to like a little more large size. and 16% of them wanted a little more small size. We expect that there will be the effect of sale by indicating brix degree in the case of 'Vlibaekdo' in the brix degree higher than 13?x being produced in large quantities. We think that it will be desirable for packing house over a village unit not a farm to select and sale by brix degree becase of a farmer meeting more fixed cost than packing house.

數學敎育의 現況分析과 改善方案 (Ⅱ) : 中·高校 數學科 運營과 敎師 現況分析 Analysis of administrations and teachers of today's math. department in the middle and high schools

林在圭,奇宇恒,金演哲,金正遠 慶北大學校 師範大學 1981 敎育硏究誌 Vol.23 No.-

Owing to the curriculum's revision of primary and high school in the beginning of 1970, several elementary concepts of modern mathematics were introduced as new teaching contents. So the efficient ways to reeducate the present teachers and to publish a desirable textbook have been badly needed. In this paper, we investigate the present situations of administration and teachers of mathematics department in the city and rural area. On the basis of these results, we find out the better ways of mathematics education from the following points of view: 1. The general administrations of mathematics department. 2. The reeducation and education for mathematics teachers. 3. Mathematics textbooks. 4. Evaluations and tests.