일반화된 골드바흐 추측과 타원 곡선의 산술에 관하여

학위논문 (박사)-- 서울대학교 대학원 : 자연과학대학 수리과학부, 2018. 2. 변동호.In this thesis, we introduce a totally new method which constructs integral points of elliptic curves. The main idea is that results on the theory of excep- tional sets of linear type generalizations of strong Goldbach conjecture show the existence of integral points of certain elliptic curves, which are called cubic twists. We first show that the size of exceptional sets of linear type generaliza- tions of strong Goldbach conjecture is relatively small by generalizing previous works. We also explain why this result can be used for constructing integral points of elliptic curves. After that we give two applications about the theory of elliptic curves. One is that there are infinitely many sums of two rational cubes which have arbitrary number of prime divisors. The other is that under the parity conjecture, there are infinitely many elliptic curves whose Mordell–Weil groups are exactly Z × Z.1 Introduction 1 2 Preliminaries 3 2.1 Circle method 3 2.2 Elliptic curves 6 3 Exceptional set of Goldbachs problem 13 3.1 Main theorem 13 3.2 Minor arc 16 3.3 Major arc 21 4 Sum of two rational cubes 33 4.1 Previous results and Main theorem 33 4.2 Some properties of E_n 35 4.3 Proof of the first application 37 5 Ranks of family of elliptic curves 39 5.1 Mordell–Weil group of a family of elliptic curves 39 5.2 Proof of the second application 40 Bibliography 43Docto

Combination of macrophage inflammatory protein 1 alpha with existing therapies to enhance the antitumor effects on murine hepatoma

Existing therapies such as irradiation or sorafenib have limited success in the treatment of hepatocellular carcinoma (HCC) due to tumor recurrence and metastasis. Therefore, combination with other therapeutics is often considered. Macrophage inflammatory protein-1 alpha (MIP-1α) is a member of a family of chemoattractant cytokines that can induce the migration of monocytes, which in turn can play a role in fighting tumors. This study investigated whether intravenous injection of MIP-1α in conjunction with irradiation or sorafenib could enhance the antitumor effects on murine hepatoma. An HCa-I tumor was grown on the right thigh of each C3H/HeN mouse. Mice were then treated with 10 Gy of irradiation, sorafenib, or a combination of MIP-1α with either irradiation or sorafenib, and antitumor and antimetastatic effects were then investigated. To understand the mechanisms, changes in the level of immunological markers were also evaluated. Combination treatment of MIP-1α with irradiation or sorafenib resulted in a significant enhancement of antitumor effects, prevention of lung metastasis and increase in host survival. This was achieved by significantly increasing the levels of the immunological markers: Cluster Differentiation (CD) 8, CD107A and CD11C. We conclude that a combination treatment of MIP-1α with irradiation or sorafenib would be a useful strategy for management of hepatoma.ope

학생주도 인지적 도식화 전략이 초등학교 읽기장애 학생의 읽기 이해력과 읽기 전략 사용 능력에 미치는 효과

읽기 이해는 모든 교과학습에 기초가 되며 사회생활에서도 그 중요성이 강조되고 있다. 하지만 읽기장애 학생들은 읽기 이해에 있어 읽기전략을 적절히 사용하지 못하고, 읽기에 대한 낮은 동기로 인하여 읽기에 수동적으로 접근하여 읽기 이해에 어려움을 가진다. 따라서 이러한 읽기장애 학생의 읽기 이해 어려움을 돕기 위한 적절한 교육이 필요하다. 선행연구들에 의하면, 학생주도 인지적 도식화 전략은 읽기장애 학생에게 글의 구조를 시각화해주고, 학생의 동기에게 동기를 부여해줌으로써 학생의 적극적인 참여를 유도하여 학생의 읽기 이해력과 읽기 전략 사용능력을 향상시키는데 효과적이라고 하였다. 따라서 본 연구의 목적은 학생주도 인지적 도식화 전략을 읽기장애 학생들에게 교수했을 때, 읽기 이해력과 전략사용능력에 미치는 효과를 알아보는 데 있다. 이를 위해 본 연구는 서울 시내 초등학교 4, 5학년에 재학중인 읽기장애 학생20명(4학년 16명, 5학년 2명)을 연구 대상으로 선정하였다. 학생주도 인지적 도식화 전략 훈련의 유무에 따라 실험집단과 통제집단으로 10명씩 구성하였으며, 10회기동안 40분씩 교수를 제공하였다. 실험집단은 초등학교 1~4학년 국어 교과서와 교사용 지도서에 수록된 설명문을 정의구조, 예시구조, 열거구조, 비교/대조구조, 시간/공간순서구조, 원인/결과구조, 문제해결의 7가지 기본 구조와 혼합구조로 나누어 각 구조에 맞는 도식을 구성하고 읽기 이해문제를 해결하는 전략을 직접교수법으로 지도했으며, 통제집단은 같은 훈련 자료를 반복적으로 읽기, 밑줄 긋기, 질문하기 등으로 지도하였다. 읽기 이해력을 검사하기 위한 검사도구는 사실적인 이해, 추론적인 이해, 적용적인 이해를 측정하는 항목으로 구성하였으며, 사전·사후검사에 동형 검사지를 사용하였다. 전략 사용 능력 검사는 사전·사후에 동일한 글을 사용하였는데, 학생들이 제시된 글을 읽고 도식을 구성한 것을 연구자가 미리 구성한 기준도식과 비교하여 분석하였다. 검사 결과 처리는 읽기 이해력과 전략사용 능력 검사 결과를 점수화 한 후, SPSS Package를 이용하여 공분산 분석을 실시하였다. 본 연구의 결과는 다음과 같다. 첫째, 학생주도 인지적 도식화 전략을 훈련받은 실험집단은 통제집단에 비해 전반적인 읽기 이해력이 유의하게 향상되었다. 또한 읽기 이해력을 하위 기능으로 나누어 학생주도 인지적 도식화 전략이 학 생들의 읽기 이해력에 미친 효과를 검증해본 결과 실험집단의 하 위기능상 읽기 이해력(사실적, 추론적, 적용적)이 유의하게 향상되 었다. 둘째, 학생주도 인지적 도식화 전략을 훈련받은 실험집단은 통제집단 에 비해 읽기 전략 사용 능력이 유의하게 향상되었다. 요약하면, 학생주도 인지적인 도식화 전략은 초등학교 읽기장애 학생의읽기 이해력과 읽기 전략 사용 능력에 효과가 있음을 알 수 있다. 이러한 연구 결과는 학생주도 인지적 도식화 전략이 읽기장애 학생들의 읽기 이해력을 돕기 위한 읽기 전략으로 활용될 수 있을 것이라는 가능성을 시사해준다. 따라서 읽기장애 학생들에게 학생주도 인지적 도식화 전략을 교수함으로써 통합교육 상황에서 읽기 이해뿐만 아니라 모든 교과 학습능력을 향상시킬 수 있을 것이다. ; The purpose of this study was to examine the effects of Student-Initiated Cognitive Mapping on literal, reasoning and applicative reading comprehensions and reading strategy skill of elementary students with reading disability. For this purpose, 20 4th and 5th graders were selected. They were divided into two groups, experimental and control, by 10 subjects each. In the experimental groups, the subjects were trained by the direct instruction method of student-initiated cognitive mapping strategy with expository text structures. Each expository text structure was composed of seven basic structures-Definition, Example, Enumeration, Comparison/Contrast, Temporal/Locational, Causation, Problem/solving- and Mixed structures. For the control group, the traditional teaching method of repeated reading and asking questions was used. This experiment was conducted for 10 40-minute sessions each day. To test the effects of this experiment, pre and post tests of reading comprehension and reading strategy skill were used. The data collected were analyzed by ANCOVA utilizing pretest scores of reading comprehension and reading strategy skill as covariates. The results obtained in this study are as follows: 1. A significant difference was found between the experimental and the control group in literal, reasoning, and applicative reading comprehension, showing significantly higher performance in the experimental group student-initiated cognitive mapping strategy. 2. In terms of reading strategy skills, a significant difference was found between the two groups. Participants showed significantly higher performance in the experimental group of student-initiated cognitive mapping strategy. Based on the results mentioned above, it could be concluded that the student-initiated cognitive mapping strategy is an effective method of improving the reading comprehension and reading comprehension skill of elementary students with reading disability.논문개요 = vi I. 서론 = 1 A. 연구의 필요성 및 목적 = 1 B. 연구 문제 = 5 C. 용어 정의 = 6 II. 이론적 배경 = 8 A. 읽기 이해의 개관 = 8 B. 읽기장애 학생의 읽기 이해 = 14 C. 인지적 도식화 전략의 개념 및 유형 = 18 D. 학생주도 인지적 도식화 전략 = 21 1. 학생주도 인지적 도식화 전략의 개념 = 21 2. 학생 주도 인지적 도식화 전략의 이론적 근거 = 23 3. 학생주도 인지적 도식화 전략 교수 = 24 4. 학생주도 인지적 도식화 전략을 이용한 교수의 효과 = 31 III. 연구 방법 = 37 A. 연구대상 = 37 B. 실험도구 = 39 C. 실험절차 = 47 D. 자료 분석 = 50 IV. 연구 결과 = 51 V. 논의 및 제언 = 61 A. 논의 = 61 B. 연구의 제한점 = 66 C. 제언 = 68 참고문헌 = 70 부록 = 78 영문 초록 = 12

서울시 수돗물 수질개선의 가치측정과 심리적 계정 편의 : 이중 양분선택 조건부 가치측정법

학위논문(석사)--서울대학교 대학원 :자원공학과,1998.Maste

Chronological changes of mechanical allodynia and spinal microglia activation by an intrathecal injection of MK-801.

The neuropathic pain that occurs after peripheral nerve injury may be related to abnormal central activity. The present experiments investigated the effects of MK-801 [N-methyl-D-aspartate (NMDA) receptor antagonist] on neuropathic pain behaviors and microglial activity in rats. Neuropathic pain was produced by L5 spinal nerve ligation of rats. MK-801 was injected to determine whether spinal microglial activation after nerve injury plays a crucial role in the development and/or maintenance of neuropathy through the NMDA receptor. Mechanical allodynia of the hind paw was examined with von Frey filaments postoperatively. Microglial activity was measured by observing changes in immunoreactivity with a microglia marker, OX-42. The MK-801, at a dose of 3 or 30 µg/5 µl, injection group showed higher neuropathic pain threshold and reduction of microglial activity. These results suggest that neuropathic pain behaviors following L5 spinal nerve ligation may be related to altered activity of the microglia involving the NMDA receptor, and chronological changes of microglial activation by MK-801 are related to maintenance of mechanical allodynia.ope

Bioprocess engineering to produce 10-hydroxystearic acid from oleic acid by recombinant Escherichia coli expressing the oleate hydratase gene of Stenotrophomonas maltophilia

Microbial hydroxylation of long chain fatty acids has been extensively investigated. However, biotransformation productivity remains below ca. 1.0 g/g cell dry weight (CDW)/h under process conditions. In the present study, a highly efficient microbial hydroxylation process to convert oleic acid into 10-hydroxystearic acid was developed. A recombinant Escherichia coli expressing ohyA, the gene encoding oleate hydratase of Stenotrophomonas maltophilia, was used as the biocatalyst. Investigation of the ohyA expression and biotransformation conditions (e.g., inducer concentration, gene expression period before initiating biotransformation, mixing condition of reaction medium) enabled 10-hydroxystearic acid to accumulate to a final concentration of approximately 46 g/L in the culture medium. The specific product formation rate and product yield reached approximately 2.0 g/g CDW/h (i.e., 110 U/g CDW) and 91%, respectively. The specific product formation rate was more than 3-fold higher than those of a bioprocess using wild type Stenotrophomonas sp. cells. Additionally, the product of the whole-cell biotransformation was recovered at a yield of 70.9% and a purity of 99.7% via solvent fraction crystallization at low temperature. These results will contribute to developing a biological process for hydroxylation of oleic acid.restrictio

Neonatal capsaicin treatment in rats affects TRPV1-related noxious heat sensation and circadian body temperature rhythm

The transient receptor potential vanilloid 1 (TRPV1) is a cation channel that serves as a polymodal detector of noxious stimuli such as capsaicin. Therefore, capsaicin treatment has been used to investigate the physiological function of TRPV1. Here, we report physiological changes induced by treating neonatal rats with capsaicin. Capsaicin (50 mg/kg) (cap-treated) or vehicle (vehicle-treated) was systemically administered to newborn SD rat pups within 48 h after birth. TRPV1 expression, intake volume of capsaicin water, and noxious heat sensation were measured 6 weeks after capsaicin treatment. Circadian body temperature and locomotion were recorded by biotelemetry. Expression of Per1, Per2, Bmal1 and Hsf1 (clock genes) was also investigated. Neonatal capsaicin treatment not only decreased TRPV1 expression but also induced desensitization to noxious heat stimuli. Circadian body temperature of cap-treated rats increased significantly compared with that of vehicle-treated rats. Additionally, the amplitude of the circadian body temperature was reversed in cap-treated rats. Expression of the hypothalamic Hsf1 and liver Per2 clock genes followed a similar trend. Therefore, we suggest that these findings will be useful in studying various physiological mechanisms related to TRPV1.ope