• Title/Summary/Keyword: 유성

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Seed Germination, Seedling Growth, and Herbicidal Responses of Bidens tripartita L. (가막사리 (Bidens tripartita L.)의 종자발아, 유묘의 생장 및 제초제반응)

  • Hwang, I.T.;Choi, J.S.;Kuack, H.H.;Kim, J.S.;Lee, H.J.;Cho, K.Y.
    • Korean Journal of Weed Science
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    • v.16 no.2
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    • pp.114-121
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    • 1996
  • This study was conducted to investigate seed germination, seedling growth, and responses to herbicides of Bidens tripartita L. When the field-collected seeds were stored under a dry-room temperature, dry-low temperature, wet-low temperature, or dry-high temperature condition, no seeds were germinated in a growth chamber with 14 hr photoperiod up to 35 days after the storage. Exceptionally, however, some seeds stored under a wet-room temperature condition were germinated after 25 days of the storage. This might be due to the fact that the seed coats were damaged by fungi which developed during the storage. Seeds stored under a wet-low temperature condition (stratification) began to be germinated after 3 months of the storage and the germination rate increased with a prolonged stratification. Almost all seeds were germinated after 9 months of the stratification. These results suggest that the dormancy of B. tripartita L. seeds relate to the seed coat and thus several attempts were made to induce seed germination through damaging or weakening the seed coat. Freezing($-20^{\circ}C$), drying($100^{\circ}C$), or swelling($40^{\circ}C$) of the seeds was not effective to induce the germination. Treatments of concentrated sulfuric acid, $KNO_3$, or gibberellin to the seeds had no effect on inducing the germination. However, ethrel had a stimulatory effect on the germination of the seeds with an optimum concentration of 250ppm. A seed cutting was also effective to induce the germination, but seedlings from the seeds had cutted cotyledons. Germination of the stratified seeds varied with the temperature condition to which they were subjected, but not with light. The germination rate was the highest at 35 - $40^{\circ}C$. Although the seeds were not able to germinate under a submerged condition, seedlings after 2-leaf-stage exhibited better growth under a submerged or a subirrigated condition than under an upland condition. Among the herbicides tested, pyrazosulfuton-ethyl, linuron, and bentazone were found to be effective for controlling B. tripartita L., having more herbicidal effect with an earlier application.

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Evaluation of the Effect of Urban-agriculture on Urban Heat Island Mitigation (도시농업의 도시열섬현상 저감효과에 대한 계량화 평가연구)

  • Eom, Ki-Cheol;Jung, Pil-Kyun;Park, So-Hyun;Yoo, Sung-Yung;Kim, Tae-Wan
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.5
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    • pp.848-852
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    • 2012
  • Vegetation can make not only to lower the urban ambient air temperature (UAAT) by crop evapotranspiration (ET) and increasing solar radiation albedo, but also to reduce the urban air pollution by $CO_2$ uptake and $O_2$ emission in addition to the reducing ozone concentrations by aid of lower the UAAT. To evaluate the effect of vegetation on urban heat island mitigation (UHIM), the climate change of 6 cities during 30 years are analysed, and the amount of ET, $CO_2$ uptake, $O_2$ emission and ozone concentrations are estimated in Korea. The most hot season is the last part of July and the first part of August, and the highest average UAAT of a period of ten days was $35.03^{\circ}C$ during 30 years (1979 - 2008). The mean values of maximum ET of rice and soybean in urban area during urban heat island phenomena were 6.86 and $6.00mm\;day^{-1}$, respectively. The effect of rice and soybean cultivation on lowering the UAAT was assessed to be 10.5 and $3.0^{\circ}C$ in Suwon, respectively, whereas the differences between the UAAT and canopy temperature at urban paddy and upland in Ansung were 2.6 and $2.2^{\circ}C$. On the other hand, the urban-garden in Suwon city had resulted in lowering the UAAT and the surface temperature of buildings to 2.0 and $14.5^{\circ}C$, respectively. Furthermore, the amounts of $CO_2$ uptake by rice and soybean were estimated to be 20.27 and $15.54kg\;CO_2\;10a^{-1}day^{-1}$, respectively. The amounts of $O_2$ emission by rice and soybean were also assessed to be 14.74 and $11.30kg\;O_2\;10a^{-1}day^{-1}$, respectively. As other cleaning effect of air pollution, the ozone concentrations could be also estimated to reduce 21.0, 8.8, and 4.0 ppb through rice-, soybean cultivation, and urban gardening during most highest temperature period in summer, respectively.

Characteristics of β-casein Gene using the PCR Technique in Korean Native Goat (PCR 기법을 이용한 한국재래산양 β-casein 유전자의 특성)

  • Kim, Ji-Ae;Ryoo, Seung-Heui;Yu, Sung-Lan;Lee, Jun-Heon;Seo, Gil-Woong;Kim, Sun-Kyun;Sang, Byung-Chan
    • Korean Journal of Agricultural Science
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    • v.29 no.2
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    • pp.43-52
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    • 2002
  • This study was performed to provide the basic data for preservation and improvement of genetic resources according to finding genetic construction obtained from analysis of genetic characteristics of $\beta$-casein gene in Korean Native goat and Saanen using the PCR-RFLP. This study confirmed the amplified products of 481bp fragments obtained from the amplification of $\beta$-casein loci by PCR. The $\beta$-casein AB genotype showed 481, 284 and 197bp, and $\beta$-casein BB genotype showed 284 and 197bp fragments in Korean Native goat and Saanen. The frequencies of $\beta$-casein genotype in Korean Native goat were 6.25 and 93.75% for AA and AB and the frequencies of $\beta$-casein genotype in Saanen were 57.14 and 42.86% for AA and AB types. The frequencies of $\beta$-casein A and B alleles were 0.031 and 0.969 in Korean Native goat and the frequencies of $\beta$-casein A and B alleles are 0.286 and 0.714 in Saanen, respectively. The nucleotide sequence of $\beta$-casein gene of Korean Native goat was 97.71% higher homology with 11 nucleotide sequences difference of that of goat reported in GeneBank (M90556). Therefore, this study of molecular genetic characteristics by the analysis of genetic polymorphism and sequencing for $\beta$-casein gene should be used as basic and applying data for preservation and improvement of genetic resources in Korean Native goat breeding.

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The Differences of the Smoking Habit Between Emphysema and Chronic Bronchitis (폐기종과 만성기관지염의 흡연습관 차이)

  • Mun, Yeung-Chul;Yu, Sung-Keun;Park, Hye-Jung;Shin, Kyeong-Cheol;Chung, Jin-Hong;Lee, Kwan-Ho;Lee, Jung-Cheol
    • Tuberculosis and Respiratory Diseases
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    • v.50 no.6
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    • pp.693-703
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    • 2001
  • Background : Smoking is the most important and consistent determinant of the development and progression of COPD(Ed Note : Define COPD). The fact that cigarette smokers develop a different type of COPD, chronic bronchitis and emphysema, with different clinical and pathological aspects, suggests that the development of COPD has a relationship with other smoking-associated factors beyond just a simple smoking history. The aim of this was to analyze the smoking habits and history of patients with COPD and to evaluate the development of different types of COPD according to patient's smoking habits. Method : To evaluate the differences in the smoking patterns of patients with chronic bronchitis and emphysema, a pulmonary function test was conducted, and the smoking history and patterns was obtained through a smoking history questionnaire by a direct personal interview from 333 male cigarette smokers diagnosed with COPD, in the Yeungnam university medical center(190 patients diagnosed with chronic bronchitis, 143 patients diagnosed with emphysema). Result : The patients with emphysema smoked earlier and had a higher smoking history(ie, more packyears, more total amounts of smoked cigarette, and more deep inhalation and longer duration of plain cigarette exposure) than those with chronic bronchitis. The depth of inhalation was also significantly higher in the emphysema patients after taking into account age, cumulative cigarette consumption and the type of cigarette smoked. Conclusion : Emphysema was more associated with the increasing degree of inhalation as assessed by the depth of inhalation. A high alveolar smoke exposure may be a significant risk factor for the development of emphysema.

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Prevalence and Risk Factors of Depression in Patients with Chronic Obstructive Pulmonary Disease (폐쇄성폐질환에서 우울증상의 빈도 및 위험 인자)

  • Chin, Hyun Jung;Lee, Kwan Ho;Park, Chan Soh;Son, Chang Woo;Lee, Hi-young;Yu, Sung Ken;Shin, Kyeong Cheol;Chung, Jin Hong;Kim, Jung Youp
    • Tuberculosis and Respiratory Diseases
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    • v.65 no.3
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    • pp.191-197
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    • 2008
  • Background: Due to the irreversible nature of chronic obstructive pulmonary disease (COPD), the treatment aim in patients with COPD is not to cure but to reduce the symptoms, increase lung function, and improve the quality of life. It has been suggested that depression is a common emotional disturbance in patients with COPD who are faced with a major physical impairment and embarrassing symptoms. This study evaluated the prevalence and risk factors of depression in patients with chronic obstructive pulmonary disease. Methods: A total of 59 patients with a registered diagnosis of chronic obstructive pulmonary disease were selected. Depression was assessed using the Centers for Epidemiologic Studies Depression (CES-D) scale. The quality of life was assessed using the Korean version of the St. George's Respiratory Questionnaire. Results: The prevalence of depression was 17.0%. In the correlation model, the interaction of the $FEV_1%$ over predicted value and SGRQ score(symptom, activity, impact, overall score) was statistically significant. The interaction of the $FEV_1%$ over predicted value and depression scale(CES-D) was also statistically significant. There was a positive correlation between the SGRQ scores(symptom, activity, impact, overall score) and the depression scale. Conclusion: The prevalence of depression in patients with chronic obstructive pulmonary disease is relatively high. The pulmonary function and the living standards were found to be significant risk factors for depression.

Experiment of Flexural Behavior of Prestressed Concrete Beams with External Tendons according to Tendon Area and Tendon Force (강선량 및 긴장력에 따른 외부 강선을 가진 PSC 보의 휨거동 실험)

  • Yoo, Sung-Won;Yang, In-Hwan;Suh, Jeong-In
    • Journal of the Korea Concrete Institute
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    • v.21 no.4
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    • pp.513-521
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    • 2009
  • Recently, the externally prestressed unbonded concrete structures are increasingly being built. The mechanical behavior of prestressed concrete beams with external unbonded tendon is different from that of normal bonded PSC beams in that the slip of tendons at deviators and the change of tendon eccentricity occurs as external loads are applied in external unbonded PSC beams. The purpose of the present paper is therefore to evaluate the flexural behavior by performing static flexural test according to tendon area and tendon force. From experimental results, before flexural cracking, there was no difference between external members and bonded members. However, after cracking, yielding load of reinforcement, ultimate load, and the tendon stress of external members was lower than that of bonded members. For the relationship of load-tendon stress, the increasing of tendon strain was inversely proportional to the initial tendon force. However, even if the initial tendon force was large, the tendon strain with small effective stress was smaller than that with large effective stress. The concrete compressive strain was proportional to the effective stress of external tendon. From the comparison between test results and codes, the ACI-318 could not consider the effect of tendon force or effective stress, and especially the results of ACI-318 were very small, so it was very conservative. And the AASHTO 1994 could be influenced on the tendon area, initial force and effective stress, but as it was made on the basis of internal unbonded tendon, its results were much larger than the test results. For this reason, the new correct predict equation of external tendon stress will be needed.

Physicochemical Properties and Antioxidative Activities of Mixed Citrus and Carrot Juice (감귤당근 혼합주스의 이화학적 특성 및 항산화효과)

  • Oh, You-Sung;Hwang, Joon-Ho;Oh, Hyun-Joeng;Lim, Sang-Bin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.5
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    • pp.598-604
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    • 2012
  • Four types of mixed citrus and carrot juice (CCJ) were prepared with citrus-pressed juice and cake, and carrot-pressed juice. Their physicochemical properties and antioxidative activities were investigated. The four types of juices were created using different ratios of citrus-pressed juice, carrot-pressed juice, citrus-pressed cake, and additives. The mixing ratios of the four CCJ were as follows (all ratios given in the order of citrus-pressed juice : carrot-pressed juice : citrus-pressed cake : additives; 70:30:0:0 for CCJ-1, 65:30:0:5 for CCJ-2, 65:30:5:0 for CCJ-3, and 60:30:10:0 for CCJ-4. Acidity was low in CCJ-3 and -4 at 0.82 and 0.80, respectively, compared with 0.95 in CCJ-1. The fructose, glucose, and sucrose content was 2.11~5.76 g/100 g, 1.20~2.75 g/100 g, and 3.00~4.21 g/100 g, respectively. Total phenolic content was 1.17 and 1.22 times high as 863 and 898 mg% in CCJ-3 and -4, respectively, compared with 735 mg% in CCJ-1. DPPH radical scavenging activities of methanol extracts of CCJ-3 and -4 were 3.05 and 3.29 times as high as 58.7% and 63.3%, respectively, compared with 19.2% in CCJ-1. Superoxide anion scavenging activities were also 1.67 and 1.80 times higher in CCJ-3 and -4 than that of CCJ-1. Inhibition of NO production in methanol extracts of CCJ-4 were 1.15 and 1.57 times as high as 20.9% and 28.5%, respectively, compared with 18.2% in CCJ-1. Based on the sensory evaluation, CCJ-3 was more preferable in terms of color, flavor, taste, and overall preference than CCJ-1, -2, and -4. It was concluded that CCJ-3 made with 65% citrus-pressed juice, 30% carrot-pressed juice, and 5% citrus-pressed cake were high in antioxidative activity and the inhibition of NO production, and more preferable in terms of sensory attributes.

The Usefulness of Serum Tumor Markers as a Predictor of Peritoneal Metastasis in Patients with Gastric Carcinoma: CA 19-9 and CEA (위암 환자에서 수술 전 복막전이 예측을 위한 혈청 종양 표지자의 유용성: CA 19-9와 CEA)

  • Cheong, Oh;Joo, Jae Kyun;Park, Young Kyu;Ryu, Seong Yeop;Jeong, Mi Ran;Kim, Ho Koon;Kim, Dong Yi;Kim, Young Jin
    • Journal of Gastric Cancer
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    • v.8 no.3
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    • pp.129-135
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    • 2008
  • Purpose: The usefulness of serum tumor markers for assessing gastric carcinoma is very limited compared to that for neoplasms in other digestive organs. Many reports have shown that serum tumor markers are closely associated with the prognosis and tumor recurrence in gastric cancer patients. However, little is known about the usefulness of serum tumor markers as a predictor of distant metastasis for gastric carcinoma. Materials and Methods: With excluding the non-specific causes of elevated tumor markers, a total of 788 patients with gastric carcinoma and who were seen at our hospitals between 2004 and 2006 were included in this study. The correlation between the preoperative level of tumor makers and the clinicopathological features was analyzed. Results: CEA was significantly correlated with age, gender and nodal metastasis, but not with the depth of tumor. The CEA level was not correlated with distant metastasis, such as peritoneal or hematogenous metastasis. In contrast, the CA 19-9 level was significantly correlated not only with the depth of tumor and nodal metastasis, but also with peritoneal metastasis. Especially, the patients with over 500% elevation of the CA 19-9 level had a significant risk of peritoneal metastasis. Conclusion: CA 19-9 is useful for predicting peritoneal metastasis in gastric cancer patients. It can be used efficiently in making the diagnostic and the treatment plan, in combination with other diagnostic tools, for gastric cancer patients.

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Effect of Composition of γ-Al2O3/SiO2 Mixed Support on Fischer-Tropsch Synthesis with Iron Catalyst (철 기반 촉매의 Fischer-Tropsch 합성에서 γ-Al2O3/SiO2 혼합 지지체 조성의 영향)

  • Min, Seon Ki;No, Seong-Rae;You, Seong-sik
    • Korean Chemical Engineering Research
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    • v.55 no.3
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    • pp.436-442
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    • 2017
  • Fischer-Tropsch synthesis is the technology of converting a syngas (CO+$H_2$) derived from such as coal, natural gas and biomass into a hydrocarbon using a catalyst. The catalyst used in the Fischer-Tropsch synthesis consists of active metal, promoter and support. The types of these components and composition affect the reaction activity and product selectivity. In this study, we manufactured an iron catalyst using ${\gamma}-Al_2O_3/SiO_2$ mixed support (100/0 wt%, 75/25 wt%, 50/50 wt%, 25/75 wt%, 0/100 wt%) by an impregnation method to investigate how the composition of ${\gamma}-Al_2O_3/SiO_2$ mixed support effects on the reaction activity and product selectivity. The physical properties of catalyst were analyzed by $N_2$ physical adsorption and X-Ray diffraction method. The Fischer-Tropsch synthesis was conducted at $300^{\circ}C$, 20bar in a fixed bed reactor for 60h. According to the results of the $N_2$ physical adsorption analysis, the BET surface area decreases as the composition of ${\gamma}-Al_2O_3$ decreases, and the pore volume and pore average diameter increase as the composition of ${\gamma}-Al_2O_3$ decreases except for the composition of ${\gamma}-Al_2O_3/SiO_2$ of 50/50 wt%. By the results of the X-Ray diffraction analysis, the particle size of ${\alpha}-Fe_2O_3$ decreases as the composition of ${\gamma}-Al_2O_3$ decreases. As a result of the Fischer-Tropsch synthesis, the CO conversion decreases as the composition of ${\gamma}-Al_2O_3$ decreases, and the selectivity of C1-C4 decreases until the composition of ${\gamma}-Al_2O_3$ was 25 wt%. In contrast, the selectivity of C5+ increases until the composition of ${\gamma}-Al_2O_3$ is 25 wt%.

An Experimental Study on Radioprotective Effect of DDC, MEA, and WR-2721 (DDC, MEA, WR-2721의 방사선(放射線) 방호효과(防護效果)에 관(關)한 연구(硏究))

  • Chung, In-Young;Koh, Joo-Hwan;Chung, Hyun-Woo;Chil, Soo-Yil;Yoo, Seong-Yul;Koh, Kyoung-Hwan
    • Journal of Radiation Protection and Research
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    • v.11 no.2
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    • pp.114-122
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    • 1986
  • At present, the treatments of the radiation-induced diseases are only performing by the palliative treatment technique. Moreover, radiation protective agents are a little toxic for human being and this seriously limits their applicability with various complications in clinical uses. Accordingly, as a part of the aim of gain of the basic data for protective roles of some radioprotectors, the present investigation was carried out to evaluate the comparative radioprotective effects by the administration of DDC, MEA, WR-2721. Results are shown for statistically significant analysis and correlation with each group as follows; 1. The proper doses of the radioprotectors were DDC; 1,550 mg/kg, MEA; 450 mg/kg, WR-2721; 780 mg/kg of the mouse body weight. 2. DMF(Dose modification factor) of LD 50/10 and LD 50/30 for whole body irradiation was DDC; 1.2, MEA; 1.4, WR-2721; 1.9 and DDC; 1.7, MEA; 1.8, WR-2721; 2.5 respectively. 3. DMF for radiation reaction of jejunal crypt was DDC: 1.07, MEA: 1.21 and WR-2721: 1.76 and that of jejunal crypt cell was DDC: 1.04, MEA: 1.08 and WR-2721: 1.38 respectively. 4. Conclusively, WR-2721 was the most effective drung among the three radioprotectors and this result must be a supportive data for further study for clinical application.

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