• 대한치매학회지
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• 제22권4호
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• pp.148-157
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• 2023

Background and Purpose: Episodic memory is a system that receives and stores information about temporally dated episodes and their interrelations. Our study aimed to investigate the relevance of episodic memory to time perception, with a specific focus on simultaneity/order judgment. Methods: Experiment 1 employed the simultaneity judgment task to discern differences in time perception between patients with mild cognitive impairment or dementia, and age-matched normals. A mathematical analysis capable of estimating subjects' time processing was utilized to identify the sensory and decisional components of temporal order and simultaneity judgment. Experiment 2 examined how differences in temporal perception relate to performance in temporal order memory, in which time delays play a critical role. Results: The temporal decision windows for both temporal order and simultaneity judgments exhibited marginal differences between patients with episodic memory impairment, and their healthy counterparts (p = 0.15, t(22) = 1.34). These temporal decision windows may be linked to the temporal separation of events in episodic memory (Pearson's ρ = -0.53, p = 0.05). Conclusions: Based on our findings, the frequency of visual events accumulated and encoded in the working memory system in the patients' and normal group appears to be approximately (5.7 and 11.2) Hz, respectively. According to the internal clock model, a lower frequency of event pulses tends to result in underestimation of event duration, which phenomenon might be linked to the observed time distortions in patients with dementia.

• 농촌의학ㆍ지역보건
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• 제27권2호
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• pp.55-66
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• 2002

본 연구는 농촌사회의 사회적 지지에 영향을 미치는 사회경제적 요인을 밝히고, 이것이 개인의 건강증진행동과 어떠한 관련성을 갖는지를 분석하여 농촌사회 건강증진 정책에서의 사회적지지 향상 방법을 제안하고자 하였다. 2002년 7월 강원도 춘천시 2개리에 거주하는 주민 전수를 대상으로 하여 수행되었으며, 만성 중증질환이 없는 건강한 사람을 분석대상으로 선정하였다. 사회적 지지는 기능적 사회적지지 평가를 위한 변형한 한국어판 MOS-SSS(Medical Outcome Study-Social Support Survey)와 구조적 사회적지지 평가항목을 추가한 설문지를 이용하였고, 건강증진행동은 금연 금주 의도, 운동, 건강진단, 보건교육 참여, 폐경기 호르몬 치료 여부를 설문을 통해 측정하였다. 사회적 지지는 교육정도가 낮거나, 이혼이나 사별인 경우, 의료보호대상인 경우 낮았고, 사회계층이 높은 계층에서 높았으며 건강상태별로는 유의한 차이를 보이지 않았다. 건강증진행동과의 관련성 분석에서, 사회적 지지가 높은 사랑들이 건강검진율, 보건교육 참석률, 폐경기 호르몬치료율이 높음을 알 수 있었다. 음주량 흡연량을 보정한 금연 금주 의도는 사회적 지지가 높은 군에서 오히려 낮았다. 본 연구의 결과를 통해, 사회적 지지가 약한 의료보호대상, 이혼 사별가정, 저교육층에 대해 지역사회가 제공할 수 있는 기능적, 구조적 사회적 지지를 우선적으로 시행해야 하며, 농촌지역의 건강증진 보건프로그램에 사회적 지지서비스를 적극 반영해야 함을 제안하고자한다.

• 한국산학기술학회논문지
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• 제13권10호
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• pp.4927-4935
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• 2012

강황은 다양한 약리활성을 가진 약초이다. 강황에 포함된 curcumin, demethoxycurcumin(DMC)과 bisdemethoxycurcumin(BDMC)을 침적과 초음파방법을 이용하여 추출하였다. 그리고 고체상추출(SPE)을 사용하여 추출효율을 확인 하였다. 추출액은 3가지 상업용 $C_{18}$ 역상 고성능 액체 크로마토그래피에 의해 이동상으로 물과 아세토나이트릴을 사용하여 일정용매법으로 동시분리 분석을 하였다. 유속은 1.0mL/min, 주입부피는 $10{\mu}L$, 컬럼오븐 온도 $40^{\circ}C$, 파장 425nm에서 수행되었다. 실험결과, RS tech column을 사용하고 물과 아세토나이트릴의 조성비가 (50 : 50vol%)일 때 최적 조건을 얻을 수 있었다. 용매조성(물과 메탄올)에 따른 추출 수율에의 영향을 살펴본 결과 100% 메탄올에서 curcuminoids(추출시간 4h)가 가장 많이 추출되었고, 수용성 메탄올 조성보다 함량이 높았다. 100% 물에 의해, 고체상추출은 curcuminoids의 추출함량(mAU${\times}$mim)이 침적과 초음파방법보다 24.5와 14.3배 높았다. 이상의 결과는 제약 및 기능성 소재로서의 응용 가능성을 나타내었다.

• 대한간호학회지
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• 제10권2호
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• pp.21-40
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• 1980

In order to take cue of the dying persons and their survivors in a more positive and affirmative atti-tube. and to understand the valuable meaning of and dying. a survey was performed to 550 cases of health care personnels including 116 nursing students. 238 medical students. 137 nurses. and 59 doctors. Samplings were made through census Procedure from the entire group of medical and nursing students in College of Medicine. Chung-Ang University. and of licenced nurses and doctors in Chung-Ang University Hospital. and in Han-Gang Sacred Heart Hospital from the first to the end of march. 1980. These collected data were computerized at KIST by SPSS programming and were statistically analyzed by chi-square test. Through content analysis of the word associated with death and descriptive analysis of the death-re-lated variables. the following conclusion in is reached. First. Total numbers of death-word percieved by health care personnels were 198 kinds. Among them, 40 kinds of words associated with death were responded from than 1% of the total. As to the 10 death related word responded by free word association method. it was revealed that individual average number of death related word was 7.70 word. which came from higher number of words in the senior students (8.96 word) or the graduates (8.10 word) compared with the freshman (6.84 word). Second. In Content specific analysis of the death related word. more frequently perceived types summarized as the following order; the affective context of death. the diseases. the disasters. the religion, the funeral ceremonies. the separation, the drakness. and the life. Third. The most prevalent 10 words associated with death which the the respondents gave response to the the first recalling word. were as following o order； the dieases. the sadness, the vanity. the darkness, the frustration. the suicide. the incurable dieases, the graves. the dead. and the catastrophes. By sex, the diease is outstanding in females, but the vanity is in males. By occupation. the vanity and the dead was frequently observed in student group including senior students. while the incurable dieases presented by doctors. Fourth. In health care personnels. the first perceived ages of death were 11.47 $\pm$3.33 years (8.14- 15.80 years). Among them. senior students were inclined to percept death at the earliest age of life (11.28years). while doctors and nurses perceived death later in their life (12.98 years). Fifth, It is revealed in this survey that the most frequently responded death perceiving motives by health care personnels ar“psychological conflict”and“death of those around them”. Death perceiving motives can be classified in two factors; personality and life circumstances. Sixth It is of interest that only 11.3% health care personnels was found to feel death as inevitable or acceptable event. whereas 58.3% deny or reject it.

• Archives of Plastic Surgery
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• 제37권5호
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• pp.509-518
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• 2010

Purpose: Major drawbacks of conventional bone marrow stromal cells (BSCs) transplantation method are mainly caused by direct transplanted cell to host cell interactions. We hypothesized that separation of the transplanted cells by a microporous membrane might inhibit most of the potential adverse effects and induce superior effect. The purpose of the study is to determine the optimal condition of the microporous membrane. Methods: First, BSCs were placed in polyethylene terephthalate (PET) transwell inserts with 3, 8, or $12{\mu}m$ pore size, and cultured in 24 well culture plates. After 5 days, bottoms of the plates were observed for presence of attached BSCs in monolayer and cell numbers were evaluated. Second, BSCs were placed PET, polycarbonate (PCT), and mixed cellulose esters (MCE) transwell inserts with 3 and $8{\mu}m$ pore size, and cultured in 24 well culture plates. After 3 days, the supernatants of the media left in culture plate were analyzed for collagen, vascular endothelial growth factor (VEGF), platelet derived growth factor BB (PDGF-BB), and basic fibroblast growth factor (bFGF). Third, BSCs were placed in 15% and 70% of the PET membrane with $3{\mu}m$ pore size. All the experimental conditions and methods were same as the second study. Results: The optimal pore sizes to prevent BSC leakage were $3{\mu}m$ and $8{\mu}m$. The amounts of type I collagen and three growth factors tested did not show significant differences among PET, PCT, and MCE groups. However, the collagen, VEGF, and bFGF levels were much higher in the high (70%) density group than in the low (15%) density group. Conclusion: This study revealed that the optimal pore size of membrane to prevent direct BSC to recipient cell contact is in between $3{\mu}m$ and $8{\mu}m$. Membrane materials and pore sizes do not influence the collagen and growth factor passage through the membrane. The most striking factor for collagen and growth factor transport is pore density of the membrane.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1247-1247
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• 2001

Constituents of animal biofluids such as milk, blood and urine contain information specifically related to metabolic and health status of the ruminant animals. Some changes in composition of biofluids can be attributed to disease response of the animals. Mastitis is a major problem for the global dairy industry and causes substantial economic losses from decreasing milk production and reducing milk quality. The purpose of this study was to investigate potential of NIRS combined with multivariate analysis for cow's mastitis diagnosis based on NIR spectra of milk, blood and urine. A total of 112 bulk milk, urine and blood samples from 4 Holstein cows were analyzed. The milk samples were collected from morning milking. The urine samples were collected before morning milking and stored at -35$^{\circ}C$ until spectral analysis. The blood samples were collected before morning milking using a catheter inserted into the carotid vein. Heparin was added to blood samples to prevent coagulation. All milk samples were analyzed for somatic cell count (SCC). The SCC content in milk was used as indicator of mastitis and as quantitative parameter for respective urine and blood samples collected at same time. NIR spectra of blood and milk samples were obtained by InfraAlyzer 500 spectrophotometer, using a transflectance mode. NIR spectra of urine samples were obtained by NIR System 6500 spectrophotometer, using 1 mm sample thickness. All samples were divided into calibration set and test set. Class variable was assigned for each sample as follow: healthy (class 1) and mastitic (class 2), based on milk SCC content. SIMCA was implemented to create models of the respective classes based on NIR spectra of milk, blood or urine. For the calibration set of samples, SIMCA models (model for samples from healthy cows and model for samples from mastitic cows), correctly classified from 97.33 to 98.67% of milk samples, from 97.33 to 98.61% of urine samples and from 96.00 to 94.67% of blood samples. From samples in the test set, the percent of correctly classified samples varied from 70.27 to 89.19, depending mainly on spectral data pretreatment. The best results for all data sets were obtained when first derivative spectral data pretreatment was used. The incorrect classified samples were 5 from milk samples,5 and 4 from urine and blood samples, respectively. The analysis of changes in the loading of first PC factor for group of samples from healthy cows and group of samples from mastitic cows showed, that separation between classes was indirect and based on influence of mastitis on the milk, blood and urine components. Results from the present investigation showed that the changes that occur when a cow gets mastitis influence her milk, urine and blood spectra in a specific way. SIMCA allowed extraction of available spectral information from the milk, urine and blood spectra connected with mastitis. The obtained results could be used for development of a new method for mastitis detection.

• Membrane and Water Treatment
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• 제6권5호
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• pp.365-378
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• 2015

Herein, the preparation of anion exchange membrane (AEM) from brominated poly(2,6-dimethyl 1,6-phenylene oxide) BPPO and dimethylaniline (DMA) by phase-inversion process is reported. Anion exchange membranes (AEMs) are prepared by varying the DMA contents. Prepared AEMs show high thermal stability, water uptake (WR) around 202% to 226%, dimensional change ratios of 1.5% to 2.6% and ion exchange capacities (IECs) of 0.34 mmol/g to 0.82 mmol/g with contact angle of $59.18^{\circ}$ to $65.15^{\circ}$. These membranes are porous in nature as confirmed by SEM observation. The porous property of membranes are important as it could reduce the resistance of transportation of ions across the membranes. They have been used in diffusion dialysis (DD) process for recovery of hydrochloric acid (HCl) from the mixture of HCl and ferrous chloride ($FeCl_2$). Presence of $-N+(CH_3)_2C_6H_5Br^-$ as a functional group in membrane matrix facilitates its applications in DD process. The dialysis coefficients of hydrochloric acid ($U_H$) of the membranes are in range of 0.0016 m/h to 0.14 m/h and the separation factors (S) are in range of 2.09 to 7.32 in the $HCl/FeCl_2$ system at room temperature. The porous membrane structure and presence of amine functional group are responsible for the mechanism of diffusion dialysis (DD).

• 공업화학
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• 제24권3호
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• pp.305-313
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• 2013

본 연구는 glycidyl azide polymer (GAP)계 에너지 함유 열가소성 폴리우레탄 탄성체(energetic thermoplastic polyurethane elastomers, ETPE)를 합성한 후 탄성체의 필름 제조 공정의 열처리 조건이 물성에 미치는 영향에 대하여 고찰하였다. GAP계 ETPE는 ATR-FTIR, DSC, 그리고 DMA를 이용하여 분석하였다. GAP계 ETPE의 물성에 대한 열처리 조건의 영향은 $80{\sim}130^{\circ}C$의 온도 범위에서 1 h과 24 h의 열처리 시간을 나누어 연구를 진행하였다. 1 h의 열처리 조건에서는 $130^{\circ}C$의 열처리 온도에서 그리고 24 h의 열처리 과정에서는 $105^{\circ}C$ 이상의 온도조건에서 아자이드기의 흡수대인 $2090cm^{-1}$ 피크의 감소가 관찰되었으며, methylene chloride와 dimethylformamide 용매에 대한 필름의 용해도 또한 감소하였다. 이것은 $100^{\circ}C$ 이상 열처리 온도조건이 아자이드기의 가교 부반응을 유도할 수 있음을 나타낸다. 또한 열처리 온도가 $80^{\circ}C$에서 $110^{\circ}C$로 증가함에 따라 온도변화에 따른 저장 탄성률 곡선의 고온 고무평탄 영역이 더 높은 온도까지 확장되었으며, 이 또한 가교반응의 결과이다.

• 한국식품과학회지
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• 제13권1호
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• pp.57-66
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• 1981

인삼주성분 사포닌 및 미량성분 사포닌의 단리법에 대하여 HPLC의 응용을 검토하여 이미 보고한 바 있다. 따라서 인삼미량성분인 $Ginsenoside-Rh_1$ 및 미지성분인 $Ginsenoside-Rh_2$의 단리법을 검토하였다. 저자등의 방법에 따라 홍삼의 70% 에탄올추출액(4 kg)에서 부탄올추출액을 얻어 에틸 아세테이트로 처리 (실온에서 3시간 및 $60^{\circ}C$에서 3 시간)하여 에틸 아세테이트 획분(29g)을 preparative HPLC인 prep LC/System-500을 사용하여 부분분획하여 각 획분을 analtical HPLC/ALC-201로 동정, ginsenoside-Rh group을 다시 에테르, 에틸 아세테이트 및 물로 정제한 후, semipreparative HPLC/ALC-201로 $ginsenoside-Rh_1$ 및 $-Rh_2$를 단리했다. 미지성분단리에 HPLC의 응용이 효과적임이 판명되었다.

• 공업화학
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• 제23권3호
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• pp.313-319
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• 2012

본 연구에서는 Polyacrylonitrile (PAN)계 탄소섬유 표면에 구리도금 표면처리가 탄소섬유 강화 복합재료의 기계적 계면 특성에 미치는 영향에 관하여 관찰하였다. 탄소섬유 표면특성은 주사전자현미경, X-선 광전자 분광법, X-선 회절분석기, 접촉각 측정기로 측정하였고, 탄소섬유 강화 복합재료의 기계적 계면 물성은 층간전단강도(interlaminar shear strength, ILSS)와 파괴인성(critical stress intensity factor, $K_{IC}$)측정을 통하여 알아보았다. 실험결과로부터, 기계적 계면물성은 탄소섬유 표면에 COOH group과 도금된 구리함량이 증가됨에 따라 순차적으로 증가되는 것이 확인되었으나, 도금시간을 길게 하여 과량의 구리가 도입되었을 경우 기계적 계면 물성을 도리어 감소시키는 것으로 확인되었다. 결론적으로 구리함량이 탄소섬유 복합재료의 기계적 계면물성을 결정하는 중요 요소라 판단되나, 최적의 함량이상에서는 계면분리에 의한 물성저하의 원인이 될 수 있다.