• 설비공학논문집
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• 제12권6호
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• pp.533-540
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• 2000

Condensation heat transfer characteristics have been investigated experimentally when a water vapor is condensed on the outside of a horizontal copper tube in a condenser. This problem is of particular interest in the design of a LiBr-water absorption system. Hydrophilic surface modification was performed to increase the wettability on the copper tube. The optimum hydrophilic treatment condition using acethylene and nitrogen as reaction gas is also studied in detail. The results obtained indicate that the optimum reaction gas ratio of acethylene to nitrogen for hydrophilic surface modification was found to be 7 : 3 for the best condensation heat transfer. In the wide ranges of coolant inlet temperatures, and coolant mass flow rates, both the condensation heat transfer rate and the condensation heat transfer coefficient of a hydrophilic copper tube are increased substantially, compared with those of a conventional copper tube used in a condenser. It is also found that the condensation heat transfer enhancement by the hydrophilic surface modification still emains even after a hundred cycles of wet/dry processes.

• Elastomers and Composites
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• 제35권4호
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• pp.288-295
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• 2000

가황 EPDM(ethylene-propylene-diene terpolymer) 고무를 화학적 탈황처리 방법을 통하여 가교 밀도를 감소시키고자 시도하였다. 화학적 탈황처리를 위하여 상이동 촉매(phase transfer catalyst), 알카리 금속인 sodium, triphenylphosphine 등을 탈황 조제로 사용하였으며 또한 2-butanol을 탈황반응의 반응용매로 사용한 경우에 대한 탈황처리 효과도 아울러 조사하였다. 4급 암모니움염 형태의 상이동 촉매를 탈황반응에 이용할 경우 촉매의 분자량에 따른 변화 그리고 bromide(Br) 음이온 대비 chloride(Cl)음이온 사용에 따른 변화 등을 비교하였다. Sodium(Na)을 탈황반응에 투여할 경우 Na의 사용량, 반응온도, 반응시간 그리고 반응 분위기로 이용된 수소가스의 압력 등 반응변수에 따른 탈황효과를 살펴보았다. 가교밀도를 정량적으로 나타내는 수치인 $M_c$값(가교점 사이의 수평균 분자량)을 평형팽윤법을 이용하여 실험적으로 결정하였고 가황 EPDM 고무시료의 탈황효과 분석은 탈황 전과 탈황 후 시료에 대한 $M_c$ 값을 비교함으로써 수행되었다.

• BLOOD RESEARCH
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• 제53권4호
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• pp.307-313
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• 2018

Background Primary ocular adnexal extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (POML) is the most common subtype of lymphoma involving the eyes in Thailand. We sought to assess the characteristics and treatment outcomes of patients with POML in Thailand. Methods We retrospectively reviewed patient data and included patients diagnosed with POML between January 2004 and December 2016 at Chiang Mai University Hospital and King Chulalongkorn Memorial Hospital, Thailand. We collected and analyzed patients' clinical characteristics and treatment outcomes. Results Among 146 patients with lymphoma involving the eyes, 121 (82%) were diagnosed with POML. Sixty-four (52.9%) were women with median age 58 (range, 22-86) years. The most common presenting symptom was orbital mass (71.1%). Common sites of origin were the orbit (46.3%) and lacrimal gland (34.7%). At presentation, 22.3% of patients had bilateral eye involvement. About half of patients had stage I disease (N=59, 56.2%) and 20% had stage IV. Most patients (73.3%) had a low-risk International Prognostic Index. Radiotherapy was the main treatment for patients with limited-stage disease (66.7% in stage I and 56.5% in stage II). The overall response rate was 100% with complete response rates 80%, 77.3%, and 64.7% for stages I, II, and IV, respectively. Five-year progression-free survival (PFS) and overall survival were 66.1% and 94.0%, respectively. For patients with limited-stage disease, radiotherapy significantly improved PFS compared with treatment not involving radiotherapy (5-year PFS 89.9% vs. 37.3%, P=0.01). Conclusion We revealed that POML has good response to treatment, especially radiotherapy, with excellent long-term outcome.

• Preventive Nutrition and Food Science
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• 제12권3호
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• pp.141-147
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• 2007

Cordycepin (3'-deoxyadenosine), which comes from Cordyceps militaris, the Chinese medicinal fungal genus Cordyceps, is used in the treatment of various diseases such as cancer and chronic inflammation. We recently reported that cordycepin has a novel antiplatelet effect through the down regulation of $[Ca^{2+}]_{i}$ and the elevation of cGMP/cAMP production. In this study, we further investigated the effect of cordycepin on collagen-induced platelet aggregation in the presence of cGMP-dependent protein kinase (PKG)- or cAMP-dependent protein kinase (PKA)-inhibitor. PKG inhibitor Rp-8-pCPT-cGMPS potentiated the collagen-induced platelet aggregation, but PKA inhibitor Rp-8-Br-cAMPS did not. However, both Rp-8-pCPT-cGMPS and Rp-8-Br-cAMPS reduced inhibition by cordycepin of collagen-induced platelet aggregation. Moreover, cordycepin inhibited $Ca^{2+}-dependent$ phosphorylation of both 47 kDa- and 20 kDa-protein in the presence of both PKG inhibitor and PKA inhibitor. Taken altogether, these results suggest that the inhibitory effect of cordycepin on collagen-induced platelet aggregation is associated with cGMP/PKG- and cAMP/PKA-pathways, and thus cordycepin may be an efficacious intervention against platelet aggregation-mediated thrombotic disease.

• 폴리머
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• 제33권5호
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• pp.452-457
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• 2009

다중벽 탄소나노튜브 및 전도성 고분자인 PEDOT으로 이루어진 하이브리드 나노재료를 제조하였다. 다중벽 탄소나노튜브 표면에 처리반응을 수행함으로써 -Br 특성기를 갖는 다중벽 탄소나노튜브를 제조하였으며, 이를 중합반응의 개시제로 사용하였다. 이와 함께 MMA를 사용하여 촉매와 리간드 존재 하에서 원자이동 라디칼중합 공정을 수행함으로써 다중벽 탄소나노튜브 표면에 PMMA가 공유결합된 나노복합체를 제조하였다. 미니에멀젼 중합공정을 통하여 제조된 PS 수용성 에멀젼에 EDOT과 산화가를 투입하여 산화중합을 수행함으로써 core-shell 구조를 갖는 PEDOT/PS 나노입자를 제조하였다. 실란화합물로 표면 처리한 silica 입자를 PEDOT:poly(styrene sulfonate) (PSS) 수용성 분산액에 투입한 후 표면화학 반응과정을 수행함으로써 silica 외벽에 PEDOT:PSS가 코팅된 나노입자를 제조하였다. 하이브리드 나노재료들은 TEM, FE-SEM, TGA, EDX, UV 그리고 FT-IR 등을 사용하여 분석되었다.

• 한국전문물리치료학회지
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• 제19권1호
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• pp.56-65
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• 2012

This study examines the effects of a rehabilitation program on quality of life (QOL), cardiopulmonary function and fatigue during radiotherapy for breast cancer patients. The program includes aerobic exercise, stretching and strengthening exercises. Sixty-five women participated in this study and they were asked to perform supervised exercises that last for 60 minutes five times a week for six weeks. The European organization for research and treatment of cancer-cancer (EORTC QLQ-C30) and the breast (EORTC QLQ-BR23), predicted maximal volume of oxygen consumption ($VO_{2max}$) and fatigue severity scale (FSS) were assessed before and after the rehabilitation program. The 60-minute program consisted of a 10-minute warm-up, 30-minute of aerobic exercises, and 15-minute of strengthening exercises, followed by a five-minute cool-down. Heart rates were monitored throughout the exercise class to ensure that patients were exercising at the target heart rate of 40~75% of the age-adjusted heart rate maximum. There were statistically significant differences in the changes of physical function and cancer related symptoms in the EORTC QLQ-C30 and EORTC QLQ-BR23 (p<.05). There was a statistically significant improvement in the predicted $VO_{2max}$ (p<.05), although there were no significant differences in the FSS (p>.05). The results of our study suggest that a supervised rehabilitation program may benefit the physical aspects and QOL of patients receiving radiotherapy for breast cancer.

• 한국버섯학회지
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• 제13권3호
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• pp.181-184
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• 2015

버섯은 영양소 및 풍미가 뛰어나 오래전부터 식재료로 널리 활용되고 있으며 항염증 및 항산화효능도 뛰어난 것으로 알려져 있다. 그러나 버섯의 항산화 효능은 아직 연구가 미비한 실정이다. 따라서 본 연구에서는 버섯의 항전립선암 효능을 분석하였다. 이를 위해, 식용버섯인 참송이버섯, 꽃송이버섯, 편각영지버섯, 녹각영지, 현미동충하초버섯, 잎새버섯, 석이버섯, 상황버섯 등 8종 버섯의 열수 추출물에 대한 항전립선암 효능을 전립선암 세포주인 LNCaP에서 확인한 결과 참송이버섯, 편각영지버섯 및 현미동충하초버섯이 PSA 발현을 저해하는 효능이 탁월한 것을 확인하였다.

• 한국정밀공학회지
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• 제5권4호
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• pp.48-58
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• 1988

This study was undertaken to observe the formation behavior of ferro- magnetic phase in Mn-Al-Cu Alloys. The alloy selected for this investigation was 70% Mn-29% Al-1% Cu. This pre-allyed pig was prepared to the cylinderical castings using an Induction furnace after homogenizing at $1100^{\circ}C$ for 2hr, the specimens were cooled by cooling methods. Subwequent isothermal heat treatments were followed at $550^{\circ}C$ for various periods of time at predetermined(1-1000min). The formation behavior of ferromagnetic phase was investigated by measurements of magnetic properties of the specimens at each stage of heat treatment, and optical microscopic esamination and X-Ray diffraction analyses were also employed. By this basic experimental results, the conclusions are as follows 1) In order to obtain much amount of ferromagnetic phase, the optimum average cooling rate was about 7.35-$16.4^{\circ}C$/sec($1100^{\circ}C$-$600^{\circ}C$). 2) We verified the decomposition of {\tau} phase to {\beta} -Mn and {\gamma} , as the specimens were homogenized at $1100^{\circ}C$ for 12hr, then heat-treased at $550^{\circ}C$ for 1-1000min. 3) A condition of optimum heat treatments in Mn-Al-Cu permanent mag-netic alloys showed that after homogenizing at $1100^{\circ}C$ for 2hr, the speciments were cooled in air or furnace(A) and subsequent heat treatments at $550^{\circ}C$ for 1-30min. The maximum magnetic properties were measured as follows: Air cooling; Br=1200(Gause), bHc=100(oe), (BH)max=0.07(MGOe) Furnace cooling(A);Br=950(Gauss), bhe=80(Oe), (BH)max=0.05(MGOe)

• 한국식품조리과학회지
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• 제30권4호
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• pp.480-485
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• 2014

Brown rice contains both excellent nutritional value and functional advantages. However, its utilization is limited due to its rough texture and higher concentrations of phytic acid compared to white rice. We made brown rice inoculated with Lactobacillus sakei Wikim001 having phytate activity for 12 h (BRWK-12) and 24 h(BRWK-24) at $30^{\circ}C$ and evaluated the quality characteristics in an attempt to solve these problems. The pH of brown rice inoculated with L. sakei Wikim001 was reduced time dependently. A concentration of phytic acid in brown rice inoculated with L. sakei Wikim001 was decreased as compared normal brown rice (BR). BRWK-24 showed significantly high values in the brightness, redness and yellowness (p<0.05). BRWK-24 received higher scores in texture and overall acceptability than those of BR on the sensory evaluation test. Taken together, it is expected that a treatment of L. sakei Wikim001 in brown rice is useful for the development of new fermented brown rice with reduced phytic acid.

• Journal of Electrochemical Science and Technology
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• 제9권3호
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• pp.220-228
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• 2018

This study introduced a carbon-free electrode for $Li-O_2$ cells with the aim of suppressing the side reactions activated by carbon material. Micro-particles of poly(3,4-ethylenedioxythiophene) (PEDOT), a conducting polymer, were used as the base material for the air electrode of $Li-O_2$cells. The PEDOT micro-particles were treated with $H_2SO_4$ to improve their electronic conductivity, and LiBr and CsBr were used as the redox mediators to facilitate the dissociation of there action products in the electrode and reduce the over-potential of the $Li-O_2$ cells. The capacity of the electrode employing PEDOT micro-particles was significantly enhanced via $H_2SO_4$ treatment, which is attributed to the increased electronic conductivity. The considerable capacity enhancement and relatively low over-potential of the electrode employing $H_2SO_4$-treated PEDOT micro-particles indicate that the treated PEDOT micro-particles can act as reaction sites and provide storage space for the reaction products. The cyclic performance of the electrode employing $H_2SO_4$-treated PEDOT micro-particles was superior to that of a carbon electrode. The results of the Fourier-transform infrared spectroscopic analysis showed that the accumulation of residual reaction products during cycling was significantly reduced by introducing the carbon-free electrode based on $H_2SO_4$-treated PEDOT micro-particles, compared with that of the carbon electrode. The cycle life was improved owing to the effect of the redox mediators. The refore, the use of the carbon -free electrode combined with redox mediators could realize excellent cyclic performance and low over-potential simultaneously.