• 한국염색가공학회지
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• 제30권3호
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• pp.180-189
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• 2018

To study the effect of stereoisomeric structures of curing agents on curing behaviors, thermal and mechanical properties of epoxy resins, DGEBA(diglycidyl ether of bisphenol A) epoxy resin and 3,3'- and 4,4'-DDS(diaminodiphenyl sulfone) curing agents were selected. The curing initiation temperature and activation energy of DGEBA/3,3'-DDS was lower than DGEBA/4,4'-DDS. DGEBA/3,3'-DDS has a faster curing rate and higher degree of cure than DGEBA/4,4'-DDS, suggesting that 3,3'-DDS has higher reactivity than 4,4'-DDS. Tensile strength and fracture toughness of DGEBA/3,3'-DDS was lower than those of DGEBA/4,4'-DDS, indicating that mechanical properties of the epoxy resin can be different only by the stereoisomeric difference in chemical structure of the curing agent.

• 한국의류학회지
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• 제36권7호
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• pp.703-713
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• 2012

This study analyzed the physical properties and flame retardancy of Tencel FR/Cotton complex knit fabrics in order to satisfy two aspects of eco-friendliness and functionality. The flame retardant (FR) treatment of complex knit fabrics was applied by a pad-dry-cure method for additional functionality. Tensile strength, extension, bursting strength, LOI, and flame retardancy were measured by the KS (Korean Standard) K manual. The hand value knit fabrics were measured by KES-FB system. Subsequently, tensile strength and extension of wale and tensile strength of course increased in tandem with the Tencel FR yarn content. Tencel FR/Cotton complex knit fabrics were suitable for summer-weight and for baby clothes through the KES-FB system measurements. The bursting strength of Tencel FR/Cotton complex knit fabrics decreased as the contents of the Tencel FR increased; in addition, LOI increased as the contents of Tencel FR increased. This was due to the Tencel FR flame resistance function; however, the tensile strength decreased. The optimum fiber content of Tencel FR/cotton content was 1:1. The optimum conditions of flame retardant treatment were a treatment temperature $130^{\circ}C$ and the concentration of finishing agent and assistance binder (AR4260) was 35% and 1%, respectively.

• 한국건강관리협회지
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• 제2권2호
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• pp.154-159
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• 2004

Rheumatoid arthritis(RA) is the most common inflammatory joint disease and a major cause of disability, morbidity, and mortality. It occurs worldwide, affecting approximately one percent of adults. Inflammation of the synovial membrane surrounding a joint leads to swollen, tender, and stiff joints RA has no known cure and the diagnosis is made based on clinical criteria and many different options exist for treatment. All of these factors magnify the importance of the patient-physician interaction and place a premium on the art rather than the science of medicine. The major goals of therapy for RA are to relive pain, swelling, and fatigue; improve joint function; stop joint daage, and prevent disability and disease-related morbidity. Some combination of nonsteroidal anti-inflammatory drugs(NSAIDs), steroids, and DMARDs is necessary in almost patients. In many combinations of different DMARDs or DMARDs plus biologicals are necessary for optimal control. Additionaly, all patients with RA should be educated about their disease and the therapies that will be used. Patient education is essentially early in the disease course and on going basis Much research is focused on the further development of biological agent for treatment of RA. Elucidation of the trigger or trigers for RA may allow us to begin to think about prevention of RA.

• 대한구강악안면병리학회지
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• 제42권6호
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• pp.167-174
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• 2018

Natural products are vastly utilized as a source of chemotherapeutic agents for human cancers. Kochia scopraia is traditionally used for the cure of urological and dermatological diseases. Recently, methanol extract of Kochia scoparia (MEKS) has been shown to have anti-cancer activity to various human cancers. However, there is no report demonstrating the anti-cancer activity of MEKS in human mucoepidermoid carcinoma (MEC) cells. In this study, the authors studied the effects of MEKS on the cell proliferation and underlying mechanism in YD15 human MEC cells. MEKS decreased YD15 cell proliferation proven by trypan blue exclusion assay and induced apoptosis, evidenced by cell cycle analysis and western blotting. Autophagy induction by MEKS was verified by western blotting. In addition, MEKS regulated the expression of phosphorylated Akt, phosphorylated p38 and Nrf2 protein. This results can imply that MEKS might be a potential candidate for the treatment of human MEC cells.

• 한국양봉학회지
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• 제34권2호
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• pp.137-140
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• 2019

Although honeybees (Apis mellifera) are crucial for maintenance of the ecosystem, population of honeybee has been steadily decreasing due to diseases including nosemosis. Nosemosis is a disease caused by Nosema ceranae and is now considered as a major threat to honeybees. N. ceranae is a microsporidian that stays in form of spore even before the infection, which makes it harder to control than other pathogens. People are now aware of this parasite, however, cure and preventive candidates for nosemosis are hardly found until today. In this study, in vitro experiment of Lespedeza cuneata treatment to prevent nosemosis were done using Trichoplusia ni cell line, BTI-TN5B1-4. Normal T. ni cells exhibited round shape without abnormal size. On the other hand, when N. ceranae were treated, cells deteriorated and some cells abnormally enlarged due to N. ceranae infection. Interestingly, treatment of T. ni cells with L. cuneate extract protected abnormal cell shape induced by N. ceranae infection to normal shape. Some N. ceranae spores were observed outside of the cells. Effective concentration range for N. ceranae control were experimented. Lowest concentration which can control nosemosis were 50 ㎍/mL. When the concentration of L. cuneata extract was exceeded 200 ㎍/mL, cytotoxicity started to show up.

• Elastomers and Composites
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• 제56권1호
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• pp.6-11
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• 2021

In order to develop an ultra-high-density elastomeric material for substitution of steel dynamic dampers, a new curing system and technique for high-loading of the filler were examined in this study. Mechanochemical modification of chloroprene rubber (MAH-g-CR) using an internal mixer was carried out with maleic anhydride (MAH) as a reactive monomer. The optimum amount of MAH was 10 phr and the efficient grafting of MAH on CR could be achieved at a mixing temperature of 100℃. After preparing MAH-g-CR, 50 mol% epoxidized natural rubber (ENR 50) was blended with MAH-g-CR to develop a "self-curable rubber blend system" via reaction between the functional groups of the elastomeric matrices without the curing agent and additives. The content of ENR 50 was fixed at 30 wt.% throughout evaluation of the curing behavior of the MAH-g-CR/ENR blend. Tungsten powder was added to the MAH-g-CR/ENR matrix up to 60 vol.% to obtain ultra-high-density, and the maximum density obtained was 7.57 g/㎤. Stable ts2 (scorch time) and t90 (90% cure time) could be obtained even when tungsten powder was incorporated up to 60 vol.%. In addition, the tensile strength and damping properties of MAH-g-CR/ENR containing 60 vol.% of tungsten were better than those of CR containing 60 vol.% of tungsten.

• 한국미생물·생명공학회지
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• 제50권3호
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• pp.430-435
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• 2022

The infectious bursal disease (IBD) is a highly contagious and acute poultry disease caused by Birnavirus. However, the vaccination is the only disease prevention, but several factors impeded vaccine development. Thus, a need for time to develop a novel technique for managing and treating respiratory diseases in poultry birds. Passive immunization is a hope and a possible alternative used in birds to meet this need. The current research attempted to produce egg yolk-based polyclonal antibodies against the IBD virus. The benefits of IgY include ease of extraction, lack of reaction with mammalian Fc receptors, and low production cost. Commercial layers were immunized with inactivated IBD virus subcutaneously according to the treatment regimen. The eggs were gathered daily, and yolk antibodies were extracted with the ammonium sulfate precipitation technique. The use of an indirect hemagglutination test demonstrated that IgY was IBD-specific. Until the end of the experiment, the specific IgY immunoglobulins did not lose activity when stored at 4℃. The specific immunoglobulin (IgY) treated challenged birds were demonstrated 92% recovery in comparison to the control group. The study implies that the IBDV specific IgY is an easily prepared and rich source of antibodies and offers an alternative therapeutic agent to cure IBD-infected birds.

• 콘크리트학회논문집
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• 제13권5호
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• pp.484-490
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• 2001

본 연구는 라텍스 혼입률을 5, 10, 15, 20%로 변화함에 따른 염소이온 투수성과 동결융해저항성 관점에서 라텍스 개질 콘크리트의 내구특성을 고찰하고자 한다 콘크리트에 라텍스가 혼입되고 양생되었을 때 콘크리트는 라텍스 입자의 필름막에 의해 서로 연결된 시멘트수화물과 골재가 구성된다. 이때 라텍스의 양이 증가함에 따라 콘크리트의 휨강도는 증진되나, 압축강도는 다소 저하된다. 이와 같은 휨강도의 증가는 시멘트수화물과 골재사이의 라텍스 필름막에 기인한 것이며 압축강도의 감소는 라텍스의 성분 중 부타디엔의 유연성 때문에 발생되는 것으로 판단된다. 라텍스 개질 콘크리트와 보통콘크리트의 상대 투수성을 측정하기 위하여 염소이온투과시험법을 사용하였다. 실험 결과 라텍스 개질 콘크리트의 투수성은 보통콘크리트의 투수성보다 매우 낮음을 알 수 있었다. 이것은 라텍스 미립자가 미세공극을 충전하고 라텍스 입자의 필름막에 의해 골재와 시멘트수화물이 연결되었기 때문이다. 그리고 라텍스 개질 콘크리트의 동결융해저항성은 보통콘크리트에 비해 매우 높으며, 보통콘크리트에서는 동결융해저항성을 증가시키기 위해 공기연행제를 필요로 하지만, 라텍스 개질 콘크리트에서는 적절한 양생이 이루어지면 추가적인 공기연행제는 요구되지 않는다.

• 대한한의학회지
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• 제17권2호
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• pp.100-116
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• 1996

Gastric cancer shows the most high friquency in cancers that occurs in Korea. The western medicine treatment for gastric cancer has radiation and surgery, chemical treatment. While, oriental medicine cures the gastric cancer by herb-drugs, acupunture , moxa and srigma. With just one way of treating gastric cancer can't be effective remedy. Because each medicine has a strength and weakness. Thus, it is effective treatment when two medicine combins and supplement each other. We got the following result about a trend of oriental and westernal combination treatment for gastric cancer through studing records. 1. The western medicine treats gastric cancer patient with surgery first and right after surgery. They need on assembly treatent such as chemical and immune treatment. In oriental medicine, they treats gastric cancer patients with differentiation of symptone and signs and treatment(辨證施治)[for example:incoordination between liver and stomach(肝胃不和), insufficiency of spleen and stomach(脾胃虛弱), stagnation of blood stasis and toxic agent(瘀毒內阻), deficiency of yin by stomach heat(胃熱傷陰), reinforcing both qi and blood(氣血雙虧), stagnation of damp-phlegm(痰濕凝結)] and cure for them by acupuncture and stigma, too. 2. In combination with oriental and western medical treatment principle of gastric cancer by each stage is as follows. First stage and second stage gastric cancer is cured with radical surgery mainly. After operation, the herb of invigoration of the spleen(健脾), coordination of the stomach(和胃), and smoothing the liver and regurating the circulation of qi(疏肝理氣), is used for good gastroenteric condition. The second stage patients can be concidered using in combination with chimical treatment. The third stage gastric cancer is treated with radical surgery or with temporizing surgery. After those surgery, herb-drugs treatment is used jointly. The fourth stage patients who have no extensively metastasis or local contraindication can undergo temporizing and curcuit surgical operation. Herb-drugs and chemical treatments are used together for patients after operating. If he has operating contraindication, he would be treated with herb-drugs and chemical treatment. 3. In case of using in combination with oriental and western medical treatment as follows. As for herb-drugs with chemical treatment, reinforcing both qi and blood(補益氣血), invigorate the spleen and the stomach(健脾和胃), reinforcing liver and kidney(滋補脾腎), clear out the heat and relieve the toxic agent(淸熱解毒), can be used and with radiation treatment, clear out the heat and relieve the toxic agent(淸熱解毒), promoting the production body fluid and moisturizing the vicera(生津潤燥), reinforcing both qi and blood(補益氣血), invigorate the spleen and the stomach (健脾和胃), reinforcing liver and kidney(滋補肝腎) etc, can be used. 4. According to the research of oriental and western medical combination treatment are the 5-year-survival degree with oriental and western medicine combination treatment was for better than that just with oriental or western medical treatment. Especially, it has good effect on the third, fourth stage gastric cancer. That is, the middle and the end of stage gastric cancer. 5. The merits of oriental and western medicine combination treatment are lengthers one's life and diminish the bad effect of chemical treatment and radiation treatment be near completion, prevent from relapsing, maintain the balance in their eveirenment of body and improve immunity.

• 한국산학기술학회논문지
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• 제11권5호
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• pp.1741-1746
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• 2010

본 연구는 건축자재로 널리 사용되는 PVC 바닥상재 표면을 오염성 및 정전기로부터 보호하기 위하여 기존에 사용하는 광경화형 우레탄-아크릴 수지에 내오염/대전성을 향상시킨 광경화형 내오염 코팅액 개발에 관한 것이다. PVC 바닥상재용으로 사용되는 내오염성이 없는 우레탄-아크릴 수지에 4가 암모늄을 사용한 수용성 대전방지제와 아크릴용 대전방지제, 폴리우리탄용 대전방지제를 수지의 양 대비 함량(wt%) 5~20%로 변화하여 첨가한 후 배합하여 수지의 내오염/대전성을 향상시킨 내오염 코팅액을 제조하였다. 제조한 내오염 코팅액은 코팅 층의 두께조절이 가능한 코팅(Bar-coating)을 사용하여 PVC 바닥상재에 코팅 한 후 내오염성, 대전성, 부착력, 코팅두께 등의 코팅 층 표면물성을 평가하였다. 연구결과, 수지에 수용성대전방지제 15%를 혼합하여 제조한 코팅액을 Bar-coater No.12로 코팅한 코팅표면이 전기저항($3.24{\times}10^9{\Omega}/cm^2$), 내오염도(매직 Test, 먼지부착 Test) 및 부착력(100%) 모두 가장 좋은 물성을 보였다. 전반적으로 함량이 많을수록 전기저항과 오염도에서 우수한 것으로 나타났다. 그러나 대전방지제가 과량으로 들어간 경우 migration 현상이 보이는 것을 알 수 있었다.