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Enhancement of Anticarcinogenic Potentials of Submerged-Liquid Culture of Agaricus blazei Murill on Mouse Ascites Cancer by Rice Hull (왕겨에 의한 신령버섯균사체 액체배양액의 생쥐 항복수암성 증가)

  • Kim, Young-S.;Jang, Wook-J.;Rakib, A.;Kwon, Jung-M.;Ahn, Chae-R.;Kim, So-Y.;Cho, Yong-U.;Ha, Young-K.;Kim, Jeong-O.;Ha, Yeong-L.
    • Journal of Life Science
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    • v.20 no.9
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    • pp.1402-1408
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    • 2010
  • The effects of rice hull (RH) powder on the anticarcinogenic activity of submerged-liquid cultures of Agaricus blazei Murill (AB) were assessed for mouse ascites cancers induced by mouse Sarcoma S-180 (S-180) cancer cells. Optimal growth of AB mycelia in the basal liquid culture medium, containing soybean meal, was achieved by culturing at $25^{\circ}C$ for 5 days, when evaluated by $\beta$-glucan content, Brix, and mycelial weight, relative to other culture conditions. Hot-water extract (HWE) of the submergedliquid culture of AB mycelia grown at $25^{\circ}C$ for 5 days exhibited a stronger anticarcinogenic activity, relative to HWE from other culture conditions. No such effects were obtained from AB mycelial cultures by alternative temperature-controlling cultures. Both cytotoxicity for S-180 cells and anticarcinogenic potentials for mouse ascites cancer of the HWE from AB mycelia grown in the basal medium containing 1% RH powder for 5 days at $25^{\circ}C$ were significantly (p<0.05) enhanced, relative to HWE from the AB mycelia culture of the basal medium without RH powder. These results indicate that HWE of submerged-liquid culture of AB mycelia, incubated in media containing 1% RH powder at $25^{\circ}C$ for 5 days, enhanced anticarcinogenic activity against S-180 cell-induced mouse ascites cancer, and suggest that RH powder is an excellent ingredient for the improvement of the anticarcinogenic potentials of the submerged-liquid culture of mushroom mycelia.

A Study on the Level of Air Pollution and Noise in Pusan Area (부산의 지역별 대기오염과 소음정도에 관한 조사연구)

  • Cho, G.I.;Moon, D.H.;Lee, J.T.;Sin, H.R.;Kim, Y.W.;Park, H.J.;Pae, K.T.;Lee, C.U.
    • Journal of Preventive Medicine and Public Health
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    • v.23 no.4 s.32
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    • pp.391-403
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    • 1990
  • In order to assess the degree of atmospheric pollution and noise and to contribute the health improvement of residents in Pusan, the author measured the levels of CO, $SO_2,\;NO_2$, TSP, HCHO and noise in 8 areas (industrial, residential and park areas) from January to March in 1990. The results were as follows : 1. Sasang industrial area was significantly higher($2.85{\pm}0.84ppm$) in the average concentration of CO than other areas. However, there no areas to affect the human body in terms of CO concentration. 2. In general, industrial area was significantly higher ($0.134{\pm}0.084ppm$) in the average concentration of $SO_2$ than other areas, and it was the lowest ($0.009{\pm}0.005ppm$) in the Namchon-dong area. 3. Industrial ($0.033{\pm}0.009ppm$) and residential area ($0.029{\pm}0.004ppm$) were significantly higher in the average concentration of $NO_2$ than Park area ($0.009{\pm}0.001ppm$). However, there were no areas to affect the human body in terms of $NO_2$ concentration. 4. Sasang industrial area was the highest ($580.4{\pm}415.26{\mu}g/m^3$) at the average concentration of TSP and Hae-Un Dae area was the lowest ($97.22{\pm}37.86{\mu}g/m^3$). But TSP concentration showed the level to affect the human body in most areas. 5. Industrial area was significantly higher ($2.25{\pm}1.15ppb$) in the average concentration of HCHO than residential ($1.13{\pm}0.25ppb$) and park area ($1.33{\pm}0.20ppb$). 6. Industrial area was significantly higher ($77.28{\pm}6.92dB(A)$) in the level of noise than residential ($65.77{\pm}3.76dB(A)$) and park area ($64.65{\pm}5.25dB(A)$). In comparison with regional Standard Noise Level, howeverm the average noise level of residential and park area was higher than that of the Standard. In general, the level of pollution of industrial complex areas was relatively higher than those of residential and park areas. Among the industrial areas, sasang area was worst in most items. Both $SO_2$ and TSP showed the level to affect the human body in most of studied areas. It is necessary to install a new Air Quality Standard for HCHO to screen our environmental pollution.

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Comparison of Attenuation Correction Methods for Brain SPECT Ima (Brain SPECT 영상의 Attenuation Correction 방법들에 대한 비교)

  • Jo, Jin U;Kim, Chang Ho;Na, Soo Kyung;Lee, Gui Won
    • The Korean Journal of Nuclear Medicine Technology
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    • v.16 no.2
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    • pp.120-125
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    • 2012
  • Purpose : The purpose of this study was to compare count between Chang's method and CT-based attenuation correction (AC-CT) among the attenuation correction (AC) methods for non-attenuation correction (AC-non) images of Brain SPECT (Single Photon Emission Computed Tomography). Materials and Methods : We injected $^{99m}Tc$ 37Mbq in a Hoffman 3D phantom filled with distilled water in the phantom study, and injected intravenously $^{99m}Tc$-HMPAO 740Mbq in a normal volunteer in the patient study, and then obtained Brain SPECT images with Symbia T6 of Siemens and conducted quantitative brain analysis. Transverse images to which each method was applied were rebuilt at the same position, and 6 regions of interest (ROI) were drawn on each of Slice No. 10, 20 and 30 and then the counts of AC-non, AC-CT and Chang's method were compared. Results : The mean counts of AC-non, AC-CT and Chang's method were $4606.8{\pm}511.3$, $16794.6{\pm}2429.4$, and $8752.6{\pm}896.5$, respectively, in the phantom study and $5460.8{\pm}519.6$, $15320{\pm}1171.6$ and $12795{\pm}1422.1$, respectively, in the patient study. In the phantom study, the ratio of AC-CT to AC-non was 3.70 and the ratio of Chang's method to AC-non was 1.92, and in the patient study, they were 2.85 and 2.38, respectively. Conclusion : From this study, we found that AC-CT makes higher AC than Chang's method. In addition, when Chang's method was used, AC in the patient study was higher than that in the phantom study. These results need to be considered also in other examinations.

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녹비작물과 고추재배에 의한 시설 유기토양 이화학성 변화

  • Yang, Seung-Gu;Seo, Yun-Won;Kim, Hyeon-U;Lee, Yu-Seok;Choe, Gyeong-Ju;Lee, Jeong-Hyeon
    • Proceedings of the Korean Society of Organic Agriculture Conference
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    • 2008.12a
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    • pp.87-102
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    • 2008
  • 시설재배 토양에 녹비작물 재배와 고추재배, 휴경을 반복하면서, 외부 유기자재 투입을 최소화 하고 2년 동안 토양에 물리, 화학성에 변화를 추적하여 궁극적으로 녹비작물을 이용한 유기고추 시설 무경운 재배기술을 개발 하고자 시험을 수행한 결과 1. 고추 시설재배지 녹비작물 재배가 녹비 수량 및 토양 이화학성에 미치는 영향 시설재배지의 겨울 녹비작물을 1월 30일 파종하여 4월 5일에 조사한 결과 수량은 호밀과 보리녹비가 $518{\sim}677kg/10a$로 완두콩과 헤어리베치 $287{\sim}354kg/10a$에 비하여 건물수량이 현저하게 많았다. 녹비작물의 식물체내 총질소 함량이 완두콩과 헤어리베치, 보리가 호밀에 비하여 많았으며, 보리가 타 작물에 비하여 $P_2O_5$, $K_2O$ 함량이 높았고, 두과작물인 완두콩과 헤어리베치가 화본 과인 호밀과 보리녹비에 비하여 CaO과 MgO 함량이 많았다. 녹비작물의 토양중 무기성분 고정량이 화본과인 호밀과 보리녹비의 총질소량은 10a당 $17{\sim}18kg$, $P_2O_5$, 4.7kg, $K_2O$ $31{\sim}33kg$ 수준으로, 두과 녹비작물인 완두콩과 헤어리베치에 비하여 총질소, $P_2O_5$, 양이온인 $K_2O$ 높았으나, CaO과 MgO 고정량은 큰 차가 없었다. 2. 녹비작물 재배 후작 유기재배 고추의 생육 및 수량 겨울 재배 녹비작물을 트렉터로 로터리 작업하여 토양에 환원한 후 홍고추를 2007년 4월 27일 정식하여 조사한 결과 생육에 유의적인 차이를 보이지 않았으나, 고추 수량은 호밀녹비 재배지가 헤어리베치 재배지에 비하여 증수되는 경향을 보였다. 3. 시설재배지 2차 녹비작물 재배 시 녹비수량 및 토양 이화학성 2007년 12월 18일 2차 녹비작물을 파종 재배하여 생육량을 조사한 결과 건물 수량은 10a당 호밀은 720kg, 보리는 528kg, 헤어리베치는 230kg, 완두콩과 잡초는 217kg 수준이었다. 녹비작물 생체중의 일일 증가량은 호밀과 보리는 100kg/10a/day, 헤어리베치는 10a당 65kg 정도가 하루에 증가되었다. 녹비작물의 총질소 고정량은 화본인 보리와 호밀 녹비작물이 두과작물보다 건물수량이 많아서 2배정도 많았고, 인산은 $2.7{\sim}3.7$배, 가리의 고정량은 $2.2{\sim}2.6$배 정도 많았다. 4. 녹비작물 재배 후작 무경운 고추 유기재배의 생육 및 수량 2차 녹비작물 재배 토양에 무경운으로 풋고추를 2008년 4월 1일 정식하여 재배한 결과 녹비작물 종류에 따른 고추의 생육차는 인정되지 않았으나, 고추 수량은 무처리와 보리예취 이용 처리 및 녹비 생산량이 적은 완두콩 재배지에서 많았다. 5. 녹비작물과 고추 유기재배에 따른 시설토양 이화학성의 경시적 변화 비닐온실내의 토양에 무기화학성의 경시적 변화를 추적하여 본 결과 토양 pH는 녹비작물 재배 시 증가되는 경향을 보였으나, 고추재배 후에는 다시 토양 pH가 감소되었다. 토양에 EC는 녹비작물 재배 후 감소되었으나, 고추재배 후에는 다시 토양 EC농도가 증가되었다. 1차 녹비작물 재배 후에는 토양에 증가되었으나, 고추 재배 후에는 유기물함량이 감소되는 경향을 보였다. 토양에 총질소 함량은 녹비작물 2회 재배와 첫 번째 고추재배에서 감소되는 경향을 보였으나 두 번째 고추재배에서 급격한 증가를 보였다. 인산에 함량은 녹비작물재배와 고추 재배 시 미미하지만 공히 감소되는 경향을 보였다. 토양의 양이온 치환용량과 양이온인 토양 K, Ca, Mg함량은 녹비작물과 고추재배 시 감소되는 경향을 보였고, 고추재배에서는 같은 경향을 보였다.

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Postoperative External Beam Radiotherapy for Medulloblastoma (수아세포종의 수술 후 외부 방사선치료)

  • Chun, Ha-Chung;Lee, Myung-Za
    • Radiation Oncology Journal
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    • v.18 no.2
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    • pp.101-106
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    • 2000
  • Purpose : This study was peformed to evaluate the effectiveness and tolerance of craniospinal irradiation for patients with modulloblastoma and to define the optimal radiotherapeutic regimen. Materials and Methods : We retrospectively analyzed the records of 43 patients with modulloblastoma who were treated with external beam craniospinal radiotherapy at our institution between May, 1984 and April, 1998. Median follow up period was 47 months with range of 18 to U months. Twenty seven patients were male and sixteen patients were female, a male to female ratio of 1.7:1. Surgery consisted of biopsy alone in 5 patients, subtotal excision in 24 patients, and gross total excision in 14 patients. All of the patients were treated with craniospinal irradiation. All of the patients except four received at least 5,000 cGy to the posterior fossa and forty patients received more than 3,000 cGy to the spinal cord. Results : The overall survival rates at 5 and 7 years for entire group of patients were 57$\%$ and 56$\%$, respectively. Corresponding disease free survival rates were 60$\%$ and 51$\%$, respectively, The rates of disease control in the posterior fossa were 77$\%$ and 67$\%$ at 5 and 7 years. Gross total excision and subtotal excision resulted in 5 year overall survival rates of 76$\%$ and 66$\%$, respectively, In contrast, those patients who had biopsy alone had a 5 year survival rate of only 40$\%$. Posterior fossa was a component of failure in 11 of the 18 recurrences. Seven recurrences were isolated to the posterior fossa. Four patients had neuraxis recurrences, three had distant metastasis alone and four had multiple sites of failure, all involving the primary site. Conclusion : Craniospinal irradiation for patients with moduiloblastoma is an effective adjuvant treatment without significant treatment related toxicitles. There is room for Improvement in terms of posterior fossa control, especially in biopsy alone patients. The advances in radiotherapy including hypefractionation, stereotactic radiosurgery and 3D conformal radiotherapy would be evolved to improve the tumor control rate at primary site.

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External Beam Radiotherapy Alone in Advanced Esophageal Cancer (진행된 식도암의 방사선 단독치료 성적)

  • Ahn Sung Ja;Chung Woong Ki;Nah Byung Sik;Nam Taek Keun
    • Radiation Oncology Journal
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    • v.18 no.1
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    • pp.11-16
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    • 2000
  • Purpose :We peformed the retrospective analysis to find the outcome of external beam radiotherapy alone in advanced esophageal cancer patients. Methods and Materials : One hundred and six Patients treated with external beam radiotherapy alone between July 1990 and December 1996 were analyzed retrospectively. We limited the site of the lesions to the thoracic esophagus and cell type to the squamous cell carcinoma. Follow-up was completed in 100 patients (94$\%$) and ranged from 1 month to 92 months (median; 6 months). Results :The median age was 62 years old and male to female ratio was 104 2. Fifty-three percent was the middle thorax lesion and curative radiotherapy was peformed in 83$\%$. Mean tumor dose delivered with curative aim was 58.6 Gy (55$\~$70.8 Gy) and median duration of the radiation therapy was 53 days. The median survival of all patients was 6 months and )-year and 2-year overall survival rate was 27$\%$ and 12$\%$, respectively, Improvement of dysphagia was obtained in most patients except for 7 patients who underwent feeding gastrostomy. The complete response rate immediately after radiation therapy was 32$\%$ (34/106). The median survival and 2-year survival rate of the complete responder was 14 months and 30$\%$ respectively, while those of the nonresponder was 4 months and 0$\%$ respectively (p=0.000). The median survival and 2-year survival rate of the patients who could tolerate regular diet was 9 months and 16$\%$ while those of the patients who could not tolerate regular diet was 3 months and 0$\%$, respectively (p=0.004). The survival difference between the patients with S cm or less tumor length and those with more than 5 cm tumor length was marginally statistically significant (u=0,06). However, the survival difference according to the periesophageal invasion or mediastinal tyrnphadenopathy in the chest CT imaging study was not statistically significant in this study. In a multivariate analysis, the statistically significant covariates to the survival were complete response to radiotherapy, tumor length, and initial degree of dysphagia in a decreasing order. The complication was observed in 10 patients (9$\%$). Conclusion :The survival outcome for advanced esophageal cancer patients treated by external beam radiotherapy alone was very poor. In the treatment of these patients, the brachytherapy and chemotherapy should be added to improve the treatment outcome.

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Study on the Acceptability and Effectiveness of an Oral Contraceptive Among Iud Drop-outs in Rural Korea

  • Yang, J.M.;Bang, S.;Song, S.W.;Youn, B.B.
    • Journal of Preventive Medicine and Public Health
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    • v.1 no.1
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    • pp.51-66
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    • 1968
  • During a period of about one year(November '66 to December '67), the Yonsei University College of Medicine conducted a field trial of the oral contraceptive(Ovulen) in order to study its acceptability and use-effectiveness among IUD drop-outs in Koyang county. We can summarize the outstanding findings from this investigation as follows; 1. 61.4% of the IUD drop-outs interviewed (911 women) wanted to use the pill. Most of the reasons for not wanting to use it(352 women) pertained to either use of other contraceptive methods(98) or subfecundity(150) following IUD terminations. Only 83 out of 911 women gave reasons related to the difficulty of obtaining pills. Therefore, we can state that most IUD drop-outs if still in need of a contraceptive methods are in favor of trying the pill, and especially so if this method is conveniently available. 2. The 467 women or 37% of those who terminated IUD use actually visited the clinic for medical screening, and only 11 of them or 2.4% were rejected because of pregnancy and other medical reasons such as cervical erosion, myoma, breast mass, etc. 5.5% or 25 of the 456 women who received the first cycle did not take a single pill during the study period. 3. When we defined those 431 women who accepted and took one or more tablets we found that women over age 30, with 4 or more children, and/or with a higher educational level were the best prospects for recruitment. 4. In accuracy of use, about two thirds of the users started taking the pill on the 5 th day as directed for the first three cycles, but the percentages rose sharply to about 80% in later cycles. Tardiness in starting pill use in the first cycle may have occurred partly because they had to return to the clinic monthly to get each new cycle. Among acceptors who did not quit between cycles, 80 to 90% were regular users, missing two or less tablets in each cycle. 5) More than 60% of the users felt well and sometimes lost their pre-acceptance symptoms. especially dysmenorrhea. However, 27.4% (58 women) had side effects attributable to the pill compund as nausea, vomiting, indigestion, breast tenderness, decreased lactation or breakthrough bleeding. 25.0% (53 women) also complained of medical diseases or symptoms not related to the pill, especially during the first three cycles. However, as the confidence and experience of the client and the field workers grew, the incidence of unrelated medical complaints quickly fell to a lower level in the later cycles. 6. As of the end of this study, on December 31, 1967, 49.2% (212 women) had discontinued the use of the pill for medical reasons as well as for the non medical reasons. Only one case terminated use due to a pregnancy after taking pills. The cumulative continuation rates (by the life table method), were 58.9%, 51.9%, 41.0% at the end of 3 months, 6 months and one year, respectively. These rates are lower than in the U.S. studies. Even when we add the retaking group to the first segment, the continuation rate goes up only about 5% above the first segment rates mentioned above. Possible explanations are different dosages, the newerness of the method and the use of only one point for pill distribution in the country together with a monthly return for cycle 1, 2, 3, and 4-6.

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Effects of pH Adjustment and Sodium Chloride Addition on Quality Characteristics of Surimi Using Pork Leg (pH 조절 및 소금 첨가가 돼지 뒷다리부위를 이용한 수리미의 품질특성에 미치는 영향)

  • Jin, Sang-Keun;Kim, Il-Suk;Chung, Hyun-Jung;Cho, Ju-Hyun;Choi, Yeung-Joon;Lee, Jae-Ryong
    • Food Science of Animal Resources
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    • v.27 no.1
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    • pp.35-41
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    • 2007
  • This study was conducted to determine the effect of pH adjustment and addition of sodium chloride (NaCl) on quality characteristics of pork leg surimi. The pork leg surimi was manufactured with one of following pH 3.0 or pH 11.0 adjustment and contained 2% NaCl or not; C (Alaska pollack surimi, two times washing, 0% NaCl), T1 (pork leg surimi pH 3.0 adjustment, 0% NaCl), T2 (pork leg surimi, pH 3.0 adjustment, 2% NaCl), T3 (pork leg surimi, pH 11.0 adjustment 0% NaCl), T4 (pork leg surimi, pH 11.0 adjustment, 2% NaCl). The $L^*$ and W values was increased with increasing of pH value, but the $a^*$ and $b^*$ values lower. The W values were higher (p<0.05) as addition of NaCl, but $a^*$ and $b^*$ values were lower. In textural properties, the cohesiveness was increased with increasing of pH value, however with the exception of springiness all traits were higher (p<0.05) as addition of NaCl. The breaking force and gel strength was increased with increasing of pH value. The breaking force, gel strength and breaking force u deformation were higher as addition of NaCl, but shear force lower. In sensory evaluation, the tenderness was increased with increasing of pH value and all traits of sensory evaluation also were higher (p<0.05) as addition of NaCl. There were no differences in interaction of pH adjustment and without or with NaCl on color, textural properties, breaking force, deformation, gel strength, shear force and sensory evaluation of pork leg surimi. The color, textural and physical characteristics and sensory evaluation ot T2 and T4 were similar to treatment C. Therefore, the pH 11.0 and 2% NaCl addition on process of manufacture of pork leg surimi would be recommended.

Morphological Characteristics of Growth of Rice and Barnyardgrass under Various Cropping Patterns - I. Differential Germination and Growth Characteristics (재배양식(栽培樣式)에 따른 벼와 피의 생장(生長) 및 해부형태학적(解剖形態學的) 차이(差異) - I. 재배양식(栽培樣式)에 따른 벼와 피간(間)의 발아(發芽) 및 생육특성(生育特性) 차이(差異))

  • Chon, S.U.;Guh, J.O.;Pyon, J.Y.
    • Korean Journal of Weed Science
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    • v.14 no.1
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    • pp.62-70
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    • 1994
  • This study was conducted to find out if there are some differences in germination, growth and morphological characteristics between rice(Oryza saliva) and barnyardgrass(Echinochloa crus-galli) under various cropping patterns and to abtain the fundamental information on weed control method in direct seeded rice. Rice was broadcast on soil-surface(Broadcast rice), drill seeded in soil(Drilled rice) and barnyardgrass was drill seeded in soil(Barnyardgrass) under dry(Dry condition) and water direct seeded condition(Water condition). Also rice was transplanted with 8-day seedlings(8 -day-old seedling) and 25-day seedlings(25-*day-old seedling) under transplanting condition(Transplanting condition) At 1, 2, 3, 5, 7, 10, 15 and 20 days after seeding or transplanting(DAS/T), plants were harvested to examine their germination, growth and morphology. The major results were as follows ; Until 5 DAS/T growth of rice and barnyardgrass were well established under dry condition but under water condition growth of shoots was mainly elongated. At 20 DAS/T barnyardgrass had greater plant height and shoot fresh weight than rice under direct seeded condition, while plant height and shoot fresh weight of rice was greater than those of barnyardgrass under transplanting condition. Root length of barnyardgrass was greater under the dry, drilled, direct seeded conditions than that of rice under the water, broadcast, transplanting condition, respectively. And root fresh weight of rice under direct seeded condition was similar to that of barnyardgrass but that of rice under transplanting condition was significantly greater than that of barnyardgrass. Barnyardgrass only formed mesocotyls and its length increased with increased depth of seeding. Leaf stage and leaf area of barnyardgrass was greater under the dry, drilled than those of rice under water, broadcast conditions, respectively, while those of rice was greater than those of barnyardgrass under transplanting condition. Chlorophyll contents were higher in barnyardgrass, dry direct seeded rice, transplanted rice, water direct seeded rice in descending order.

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Quantification of Temperature Effects on Flowering Date Determination in Niitaka Pear (신고 배의 개화기 결정에 미치는 온도영향의 정량화)

  • Kim, Soo-Ock;Kim, Jin-Hee;Chung, U-Ran;Kim, Seung-Heui;Park, Gun-Hwan;Yun, Jin-I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.11 no.2
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    • pp.61-71
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    • 2009
  • Most deciduous trees in temperate zone are dormant during the winter to overcome cold and dry environment. Dormancy of deciduous fruit trees is usually separated into a period of rest by physiological conditions and a period of quiescence by unfavorable environmental conditions. Inconsistent and fewer budburst in pear orchards has been reported recently in South Korea and Japan and the insufficient chilling due to warmer winters is suspected to play a role. An accurate prediction of the flowering time under the climate change scenarios may be critical to the planning of adaptation strategy for the pear industry in the future. However, existing methods for the prediction of budburst depend on the spring temperature, neglecting potential effects of warmer winters on the rest release and subsequent budburst. We adapted a dormancy clock model which uses daily temperature data to calculate the thermal time for simulating winter phenology of deciduous trees and tested the feasibility of this model in predicting budburst and flowering of Niitaka pear, one of the favorite cultivars in Korea. In order to derive the model parameter values suitable for Niitaka, the mean time for the rest release was estimated by observing budburst of field collected twigs in a controlled environment. The thermal time (in chill-days) was calculated and accumulated by a predefined temperature range from fall harvest until the chilling requirement (maximum accumulated chill-days in a negative number) is met. The chilling requirement is then offset by anti-chill days (in positive numbers) until the accumulated chill-days become null, which is assumed to be the budburst date. Calculations were repeated with arbitrary threshold temperatures from $4^{\circ}C$ to $10^{\circ}C$ (at an interval of 0.1), and a set of threshold temperature and chilling requirement was selected when the estimated budburst date coincides with the field observation. A heating requirement (in accumulation of anti-chill days since budburst) for flowering was also determined from an experiment based on historical observations. The dormancy clock model optimized with the selected parameter values was used to predict flowering of Niitaka pear grown in Suwon for the recent 9 years. The predicted dates for full bloom were within the range of the observed dates with 1.9 days of root mean square error.