• Archives of Pharmacal Research
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• 제29권2호
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• pp.113-122
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• 2006

Among the effector molecules connected with the group of cell surface receptors, Ras proteins have essential roles in transducing extracellular signals to diverse intracellular events, by controlling the activities of multiple signaling pathways. For over 20 years since the discovery of Ras proteins, an enormous amount of knowledge has been accumulated as to how the proteins function in overlapping or distinct fashions. The signaling networks they regulate are very complex due to their multiple functions and cross-talks. Much attention has been paid to the pathological role of Ras in tumorigenesis. In particular, human tumors very frequently express Ras proteins constitutively activated by point mutations. Up to date, three members of the Ras family have been identified, namely H-Ras, K-Ras (A and B), and N-Ras. Although these Ras isoforms function in similar ways, many evidences also support the distinct molecular function of each Ras protein. This review summarizes differential functions of Ras and highlights the current view of the distinct signaling network regulated by each Ras for its contribution to the malignant phenotypic conversion of breast epithelial cells. Four issues are addressed in this review: (1) Ras proteins, (2) membrane localization of Ras, (3) effector molecules downstream of Ras, (4) Ras signaling in invasion. In spite of the accumulation of information on the differential functions of Ras, much more remains to be elucidated to understand the Ras-mediated molecular events of malignant phenotypic conversion of cells in a greater detail.

• 지역사회간호학회지
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• 제12권1호
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• pp.214-225
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• 2001

The purpose of this study is to compare the characteristics of the demented elderly and normal elderly over 65 staying at home in Seoul. Here, the demented elderly are defined as the aged who score under 20 on the MMSE-K testing. The subjects were 15.104 elders in home. The method is a cross-sectional study home visiting survey with questionnaires. Data analyses were conducted by using frequency, percentage, t-test and ANOVA procedures. Results are as follows: First, general characteristics such as sex, age, marriage, education, physical health, and family characteristics such as economic level and single living showed a significant variance between demented elderly and normal elderly. Second, the demented elderly showed a significantly high point of AD and IADL. Third, in contrast with normal agents, the dementia showed a high need for assistance from the care giver but followed the same pattern. In conclusion, the above findings suggested that a social support system should be developed for the demented elderly and care givers in the home.

• 한국세라믹학회지
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• 제47권5호
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• pp.445-449
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• 2010

The purpose of this study is to improve recycling rate of the waste glasses by investigating bloating mechanism. In this study, we use waste glass(W/G) and hard clay(H/C) as raw materials. The artificial lightweight aggregates were formed by plastic forming($\phi$=10 mm) and sintered by fast firing method at different temperatures(between 700 and $1250^{\circ}C$). The physical properties of the aggregates such as bulk specific gravity, adsorption and microstructure of surface and cross-section are investigated with the sintering temperature and rate of W/G-H/C contents. As the result of the bulk specific gravity graphs, we can found out the inflection point at content of W/G 60 wt%. From the microstructure images, we considered the artificial lightweight aggregates content of W/ G over 60wt% are distributed numerous micro-pores by organic oxidation without Black Core and the artificial lightweight aggregates of W/G below 60 wt% are distributed macro-pores with Black Core.

• 천문학회보
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• 제44권1호
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• pp.79.2-79.2
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• 2019

Based on three types of 2-point statistics (galaxy clustering, galaxy-galaxy lensing, and cosmic shear power spectra) from the Deep Lens Survey (DLS), we constrain cosmology and baryonic feedback. The DLS is a deep survey, so-called a precursor to LSST, reaching down to ~27th magnitude in BVRz' over 20 deg2. To measure the three power spectra, we choose two lens galaxy populations centered at z ~0.27 and 0.54 and two source galaxy populations centered at z ~0.64 and 1.1, with more than 1 million galaxies. We perform a number of consistency tests to confirm the reliability of the measurements. We calibrated photo-z estimation of the lens galaxies and validated the result with galaxy cross-correlation measurement. The B-mode signals, indicative of potential systematics, are found to be consistent with zero. The two cosmological results independently obtained from the cosmic shear and the galaxy clustering + galaxy-galaxy lensing measurements agree well with each other. Also, we verify that cosmological results between bright and faint sources are consistent. While there exist some weak lensing surveys showing a tension with Planck, the DLS constraint on S8 agrees nicely with the Planck result. Using the HMcode approach derived from the OWLS simulation, we constrain the strength of baryonic feedback. The DLS results hint at the possibility that the actual AGN feedback may be stronger than the one implemented in the current state-of-the-art simulations.

• Structural Engineering and Mechanics
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• 제88권1호
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• pp.67-81
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• 2023

The reinforced concrete (RC) structures might need strengthening or upgradation due to adverse environmental conditions, design defects, modification requirements, and to prolong the expected lifespan. The RC beams have been efficiently strengthened using the near surface mounted (NSM) approach over the externally bonded reinforcing (EBR) system. In this study, the performance of RC beam elements strengthened with NSM-steel rebars was investigated using an experimental program and nonlinear finite element modeling (FEM). Nine medium-sized, rectangular cross-section RC beams total in number made up for the experimental evaluation. The beams strengthened with varying percentages of NSM reinforcement, and the number of grooves was assessed in four-point bending experiments up to failure. Based on the experimental evaluation, the load-displacement response, crack features, and failure modes of the strengthened beams were recorded and considered. According to the experimental findings, NSM steel greatly improved the flexural strength (up to about 84%) and stiffness of RC beams. The flexural response of the tested beams was simulated using a 3D non-linear finite element (FE) model. The findings of the experiments and the numerical analysis showed good agreement. The effect of the NSM groove and reinforcement on the structural response was then assessed parametrically.

• 터널과지하공간
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• 제7권2호
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• pp.100-107
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• 1997

In case of a fire outbreak in a uni-directional road tunnel, the flow of traffic immediately behind the fire disaster will be stalled all the way back to the entrance of the tunnel. Furthermore, when the vehicle passengers try to flee away from the fire toward the entrance of the tunnel, the extremely hot fume that propagates in the same direction will be fatal to the multitudes evacuating, but may also cause damage to the ventilation equipments and the vehicles, compounding the evacuation process. This paper will present the 3-dimensional modelling analysis of the preventive measures of such a fume propagation in the same direction as the evacuating passengers. For the analysis, the fire hazard was assumed to be a perfect combustion of methane gas injected through the 1 m X 2 m nozzle in the middle of the tunnel, and the product of $CO_2$ as the indicator of the fume propagation. From the research results, when the fire hazard occurred in middle of the 400 m road tunnel, the air density decreased around the fire point, and the maximum temperatures were 996 K and 499 K at 210 m and 350 m locations, respectively, 60 seconds after fire disaster occurred, when the fumes were driven out only towards the exit-direction of the tunnel. By tracing the increase of $CO_2$ level over 1% mole fraction, the minimum longitudinal ventilation velocity was found to be 2.40 m/sec. Furthermore, through Analysis of the temperature distribution graphs, and observation of the cross-sectional distribution of $CO_2$ over 1% mole fraction, it was found that the fume did not mix with the air, but rather moved far in a laminar flow towards exit of the tunnel.

• 대한간호학회지
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• 제37권2호
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• pp.171-178
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• 2007

Purpose. To identify trends in patient satisfaction adjusted for sociodemographic factors and health status from 1989-2003. Methods. Five repeated cross-sectional surveys were used. The study sample included 290,534 household members 20 years of age and over from the five survey periods of 1989, 1992, 1995, 1999, and 2003. Satisfaction was measured using a five-point scale, ranging from "very satisfied" to "very dissatisfied." Crude satisfaction rates, representing the proportion of patients satisfied (very satisfied or satisfied), were calculated for each survey period. Satisfaction rates adjusted for age, sex, marital status, education, and self-rated health status were calculated for each of the five years. Results. Crude satisfaction rates increased from 15.4% in 1989 to 40.5% in 2003. The proportions of satisfaction and dissatisfaction were reversed after 15 years had passed. However, the satisfaction trend was not linear throughout the different years, with 1992 being the year with the lowest satisfaction rate (9.7%). These trends in crude rates did not change even after adjusting for patient characteristics. The odds of satisfaction in 1992 were 38% lower (odds ratio 0.62, 95% CI 0.60 to 0.64) than the odds in 1989. In 2003, the odds of satisfaction were 4.01 times (95% CI 3.89 to 4.13) the odds for 1989. Older, female, married, and less-educated people were more likely to be satisfied. Patients who rated their health as 'very good' had the highest satisfaction rate, and those with "neutral" health ratings had the lowest. General hospitals achieved substantial improvement whereas pharmacies became the lowest-rated of all institutions. Conclusions. The Korean health system has achieved better patient satisfaction rates over the past 15 years. Increased health expenditure, resources, and quality improvement efforts may have contributed to this progress.

• 한국수자원학회논문집
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• 제45권2호
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• pp.151-163
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• 2012

산지하천의 자갈하상재료 분포는 최근 특정규모 홍수의 수류력에 의한 유사 이송 및 퇴적 과정에 의해 형성되며, 장갑화된 하천에서 한계수류력을 평가하는 것은 안정하도설계를 위해 중요하다. 자갈하상 하천 종단지점과 만곡부 일정구간의 세부지점에대한하상재료의입도분포를조사하고, 한계유속 및 한계수류력을 평가하였다. 자갈하상 재료에 대한 Yang의 한계단위수류력과 Bagnold의 한계수류력은 상류로 갈수록 급격히 증가했다. 계획홍수량에 근거한 무차원 전단응력은 Shields 도표에서대부분조사지점의자갈하상재료가소류사형태로이동하는것으로평가되었다. 만곡부에 대한 평균입경은 상류 유입수의 1차 수충지점에서 가장 컸으며, 반사흐름에 의한 2차 수충지점에서 두 번째로 큰 입경을 보였다. 수충직하류지점들에서상대적으로작은평균입경을보였다. 만곡부의 평균한계유속 범위는0.77~2.60m/s의 범위이며, 한계단위수류력은 경사가 급한 1차 수충부에서는 상당히 컸다. 한계수류력의 분포는 7~171W/m2의 범위로 하천 횡단보다는 종단에 따른 변화가 뚜렷했고, 만곡 외측 1차 수충지점과 반사흐름 2차 수충지점에서 크게 작용하는 것으로 평가되었다.

• 한국안광학회지
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• 제16권1호
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• pp.51-60
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• 2011

목적: 본 연구는 대학생들을 대상으로 근거리에서 낮은 가입도 멀티포컬 소프트렌즈의 시기능과 만족도를 조사하고자 시행하였다. 방법: 특별한 안질환이 없고 양안 교정시력이 20/20(1.0) 이상인 대학생 26명(남자 6명, 여자 20명)을 대상으로 단초점렌즈와 낮은 가입도(Low addition)의 멀티포컬 소프트렌즈를 피팅하였다. 2주 착용한 후, 시기능검사는 원거리와 근거리 교정시력, 입체시, 대비감도, 조절근점, 조절용이성, 폭주근점, 버전스 용이성, 근거리 선명시역을 측정하였다. 설문조사는 전반적 만족도와 선호도의 항목으로 구성하여 조사하였다. 결과: 양안으로 검사한 원거리와 근거리의 시력은 2가지 렌즈를 착용한 경우 모두 20/20 이상이었다. 원거리와 근거리 입체시, 대비감도와 버전스 용이성은 멀티포컬과 단초점 소프트렌즈에서 통계적으로 의미있는 차이가 없었다. 양안으로 측정한 조절근점, 조절용이성, 폭주근점 그리고 근거리 선명시역은 전반적으로 멀티포컬 소프트렌즈의 착용 후 단초점렌즈보다 우수하였다. 설문조사는 근거리작업과 관련된 항목에서 멀티포컬 소프트렌즈, 원거리와 관련된 항목에 단초점렌즈를 선호하고 만족하는 것으로 나타났다. 결론: 대부분의 대학생들이 근거리 작업과 관련된 시기능 유용성에서 멀티포컬 소프트렌즈가 더 좋았기 때문에 단초점 콘택트렌즈보다 멀티포컬 소프트렌즈를 선호했다. 본 연구의 결과로 멀티포컬 소프트렌즈의 착용이 장시간 근거리 시생활하는 대학생에게 유용할 것으로 사료된다.

• 식물조직배양학회지
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• 제25권6호
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• pp.453-475
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• 1998

During the 100 years since the initial discovery of meiotic phenomenon many brilliant aspects have been elucidated, but further researches based on light microscopy alone as an experimental tool have been found to have some limits and shortcomings. By the use of electron microscopy and armed with the advanced knowledges on modern genetics and biochemistry it has been possible to applu molecular technology in gaining information on the detailed aspects of meiosis. As synapsis takes place, a three-layered proteinous structure called the synatonemal complex starts to form in the space between the homologous chromosomes. To be more precise, it begins to form along the paired chromosomes early in the prophase I of meiotic division. The mechanism that leads to precise point-by-point pairing between homologous chromocomes division. The mechamism that leads to precise point-by-point pairing between homologous chromosomes remains to be ascertained. Several items of information, however, suggest that chromsome alignment leading to synapsis may be mediated somehow by the nuclear membrane. Pachytene bivalents in eukaryotes are firmly attached to the inner niclear membrane at both termini. This attached begins with unpaired leptotene chromosomes that already have developed a lateral element. Once attached, the loptotene chromosomes begin to synapse. A number of different models have been proposed to account for genetic recombination via exchange between DNA strands following their breakage and subsequent reunion in new arrangement. One of the models accounting for molecular recombination leading to chromatid exchange and chiasma formation was first proposed in 1964 by Holliday, and 30 years later still a modified version of his model is favored. Nicks are made by endomuclease at corresponding sites on one strant of each DNA duplex in nonsister chromatid of a bivalent during prophase 1 of meiosis. The nicked strands loop-out and two strands reassociate into an exchanged arrangement, which is sealed by ligase. The remaining intact strand of each duplex is nicked at a site opposite the cross-over, and the exposed ends are digested by exonuclease action. Considerable progress has been made in recent years in the effort to define the molecular and organization features of the centromere region in the yeast chromosome. Centromere core region of the DNA duplex is flanked by 15 densely packed nucleosomes on ons side and by 3 packed nucleosomes on the other side, that is, 2000 bp on one side and 400 400 bp in the other side. All the telomeres of a given species share a common DNA sequence. Two ends of each chromosome are virtually identical. At the end of each chromosome there exist two kinds of DNA sequence" simple telpmeric sequences and telpmere-associated sequencies. Various studies of telomere replication, function, and behabior are now in progress, all greatly aided by molecular methods. During nuclear division in mitosis as well as in meiosis, the nucleili disappear by the time of metaphase and reappear during nuclear reorganizations in telophase. When telophase begins, small nucleoli form at the NOR of each nucleolar-organizing chromosome, enlarge, and fuse to form one or more large nucleoli. Nucleolus is a special structure attached top a specific nucleolar-organizing region located at a specific site of a particular chromosome. The nucleolus is a vertical factory for the synthesis of rRNAs and the assenbly of ribosome subunit precursors.sors.