• 제목/요약/키워드: R2R

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Competition between Transplanted Lowland Rice and Weeds as Affected by Plant Spacing and Rice Cultivar Having Different Culm Length (수도품종(水稻品種)의 간장차이(稈長差異)가 잡초(雜草)와의 경쟁력(競爭力)에 미치는 영향(影響))

  • Kim, S.C.;Lee, S.K.;Park, R.K.
    • Korean Journal of Weed Science
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    • 제1권1호
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    • pp.44-51
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    • 1981
  • An experiment was conducted to obtain the basic information about competitive ability of rice against weeds as affected by culm length at the Yeongnam Crop Experiment Station, Office of Rural Development in 1980. More weeds were harvested from the plot of short statured cultivar, Manseogbyeo compared to the plot of Cheongcheongbyeo that was approximately 10cm taller than Manseogbyeo regardless of planting density variables. Weeds also decreased as rice population increased from $30{\times}15cm$, $40{\times}(10{\times}10cm)$ and to $10{\times}10cm$, in order. The degree of weed suppression and floristic composition was varied depending upon plant spacing and weeding regime subjected at the previous year. The degree of weed suppression became increased with increasing rice population. The degree of weed suppression at the $10{\times}10cm$ plant spacing showed as high as hand weeding subjected in the previous year. However, in terms of floristic composition, Scirpus hotarui Roxb. became dominant when rice had cultivated at $10{\times}10cm$ plant spacing in the previous year while S. hotarui and Sagittaria pygmaea Miq. were both important in the hand weeding plot. The highest grain yield of rice showed at the $10{\times}10cm$ plant spacing while no significant difference was observed between $40{\times}(10{\times}10cm)$ and $30{\times}15cm$ plant spacings for both weeding regimes and both cultivars. However, response of grain yield to weeding regime was differed in two cultivars. For Manseobgyeo, significant grain yield decreased in no weeding plot regardless of plant spacing variables. But in case of Cheongcheongbyeo, grain yield reduction was only recognized at the $30{\times}15cm$ plant spacing. Based on these result it could be concluded that Cheongcheongbyeo (10cm taller in height) seemed to be more competitive against weeds than Manseogbyeo.

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Adaptation Strategy in Dry Matter and Seed Production of Rice and Weed Species (벼와 잡초(雜草)의 건물생산(乾物生産) 및 종자생산(鐘子生産) 특성(特性)에 따른 환경적응(環境適應) 전략(戰略))

  • Kim, Soon-Chul;Moody, Keith
    • Korean Journal of Weed Science
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    • 제9권3호
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    • pp.183-200
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    • 1989
  • An experiment was conducted at the greenhouse of the International Rice Research Institute in 1987 to find out the character of dry matter production, the potential seed production ability and the ecological and physiological strategies to adaptation. For these, two rice cultivars, IR64(lowland rice) and UPLRi-5(upland rice), and seven weed species were used ; Echinochloa glabrescens Munro ex Hook. f., E. cress-galls ssp. hispidula (Retz.) Honda, E. colons (L.) Link, Monochoria vaginalis (Burin. f.), Ludwigia octovalvis Jacq.) Raven, Fimbristylis miliacea Vahl and Cyperus difformis L. Adaptation strategies of weed species varied by species. However, they had efficient seed production strategy through different ways. In general, sedge weed species (F. miliacea and C. difformis) produced great amount of seeds at the expense of seed size through greater ratooning ability and low relative dry weight for flowering. For broadleaved weed species, greater number of descendants were obtained through high plasticity and low relative dry weight for flowering (M. vaginalis) or greater growth ability through effective photosynthetic efficiency (L. octovalvis). Grass weed species, on the other hand, produced their seeds through effective growth (net assimilation rate and relative growth rate), high ratooning ability (except E. crus-galls ssp. hispidula) or low relative dry weight to maximum dry weight for flowering (E. glabrescens). The harvest indices of the weed species were considerably lower than those of rice. Fimbristylis miliacea had the greatest ratooning ability followed by C. difformis, E. colons and E. glabrescens. The greatest seed productivity was recorded by C. difformis (279, 000) and L. octovalvis (268,000) while rice produced the least number of seeds (1300-6100). Log seed weight had a negative linear relationship with log seed number (y=6.30-1.48X, $R=-0.965^{**}$). For all species plant plasticity response was not directly correlated with mortality response.

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ROC Analysis of Visual Assessments Made in Gated Blood Pool Scans of Patients with Coronary Artery Disease (관상동맥질환에서 심장풀 스캔의 육안적 평가에 대한 ROC 분석)

  • Lee, Kyun-Han;Choi, Yoon-Ho;Lee, Bum-Woo;Moon, Dae-Hyuk;Koong, Sung-Soo;Chung, June-Key;Lee, Myung-Chul;Koh, Chang-Soon
    • The Korean Journal of Nuclear Medicine
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    • 제23권2호
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    • pp.175-181
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    • 1989
  • Visual assessment of regional wall motion abnormality (RWMA) by gated blood pol scan (GBPS) serves as an useful parameter in the diagnosis, functional evaluation, and follow up in various clinical settings, but are still subject to some inherent limitations. On important problem may be the interobserver as well as intraobsever variation that may well be present due to the subjective nature of the interpretations. This study was carried out to determine the reliability and reproducibility of visual assessments made in GBPSs, and to observe the degree to which the results would be influenced by observer variation. Fifty two patients with coronary heart disease had resting GBPS and contrast ventriculography within 4 days appall. Contrast ventriculography-showed normal wall motion in 6 patients and the remaining 46 had RWMA in one or more segments. The anterior and left anterolateral views of all 52 GBPSs were analyzed by three independent observers, who selected from 5 scales, their level of confidence that there was RWMA in that segment. Reciever operating characteristic (ROC) curves for each analysis was plotted and the area under the curve $(\theta)$ was used as a parameter representing each observer's performance in his interpretations. The findings of contrast ventriculographies were used as the standard for RWMA. The apical and inferoapical segments showed the best correlation with contrast ventriculography ($\theta=0.90-0.94$, 0.81-0.94, respectively), and the inferior wall showed the poorest correlation $(\theta=0.70-0.74)$. The interpretations of the inferior, septal, apical, and posteroinferior, segments showed no difference between the observers, but there was significantly better performance in assessment by observer A compared to that by B or C for the anterolateral segments ($\theta=0.87$, 0.78, 0.76, respectively. p<0.01 for A vs B, p<0.05 for A vs C), as well as when all segments were considered altogether ($\theta=0.88$, 0.83, 0.82, respectively. both p<0.05). This was also true for the infero-apical segment between A and C ($\theta=0.09$, 0.81, p<0.05). The intraobserver variation, however, did not appear significant, with only the inferior segment for observer B showing any significant difference when observer A and B repeated the analysis 10 days latter. There was no difference in assessing dyskinesia, with all observers showing a high performance ($\theta=0.98$, 0.87, 0.97, respectively). The visual assessment of left ventricular ejection fraction by all three observers correlated well with the calculated value from a semiautomated method (Spearman's r = 0.91, 0.83, 0.83. p<0.01, p<0.05, p < 0.05). The assessment of LV and RV size also correlated well between the three observers (Kendall's w = 0.80, 0.51, p<0.01 for both left and right ventricles). The above findings suggest that RWMA visually assessed by GBPS correlates well with that done by contrast ventriculography. And although the observer's experience or skill may influence the results in certain segments, visual analysis of GBPS may serve as a reliable and reproducible means for evaluating ventricular function.

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Monitoring Bacillus cereus and Aerobic Bacteria in Raw Infant Formula and Microbial Quality Control during Manufacturing (영.유아용 식품원료의 Bacillus cereus와 일반세균 모니터링 및 제조공정 중 미생물 품질제어)

  • Jung, Woo-Young;Eom, Joon-Ho;Kim, Byeong-Jo;Ju, In-Sun;Kim, Chang-Soo;Kim, Mi-Ra;Byun, Jung-A;Park, You-Gyoung;Son, Sang-Hyuck;Lee, Eun-Mi;Jung, Rae-Seok;Na, Mi-Ae;Yuk, Dong-Yeon;Gang, Ji-Yeon;Heo, Ok-Sun;Yoon, Min-Ho
    • Korean Journal of Food Science and Technology
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    • 제42권4호
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    • pp.494-501
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    • 2010
  • The purpose of this study was to examine the presence of Bacillus cereus, aerobic bacteria and coliforms in the raw material of infant formulas and investigate the manufacturing process in terms of microbial safety. Among ten kinds of raw infant formula material samples (n=20), Bacillus cereus appeared in two (n=4). Aerobic bacteria were not detected in raw infant formula material or maximum 4.15 log CFU/g. Eleven species of aerobic bacteria were isolated and 76% of them were Sphingomonas paucimobilis, Pseudomonas fluorescens, Rhizobium radiobactor, or Stenotrophomonas maltophilia. A Pearson's correlation analysis revealed that the most influential factors for detecting Bacillus cereus were aerobic bacteria and coliforms. In other words, when the measured values of aerobic bacteria and coliforms were higher, the possibility that Bacillus cereus would appear increased. In a regression model to predict Bacillus cereus, the rate of appearance was correlated with aerobic bacteria and coliforms, and its contribution rate for effectiveness was 86%. Improving microbial quality control by pasteurization, spray dry, popping and extrusion resulted in a decrease in the numbers of Bacillus cereus, aerobic bacteria and coliforms in the raw materials. The results suggest that a hazard analysis and critical control point system might be effective for reducing microbiological contamination.

Monitoring of Malachite Green in Freshwater Fish using LC-MS/MS (LC-MS/MS를 이용한 담수 어류 중 말라카이트 그린 분석)

  • Choi, Hee-jin;Yuk, Dong-Hyun;Park, Young-Ae;Jung, Bo-Kyeng;Hong, Mi-Sun;Yoon, Yong-Tae;Yi, Hye-Jin;Kim, Youn-Cheon;Park, Sung-Kyu;Kim, Moo-Sang;Jung, Kweon
    • Journal of Food Hygiene and Safety
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    • 제31권1호
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    • pp.15-20
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    • 2016
  • Malachite green was measured in 200 freshwater fish collected from local markets in Seoul using HPLC-DAD and LC-MS/MS. LC-MS/MS method was validated by linearity, accuracy, precision and limits of detection and quantification according to the CODEX's recommendation and HPLC-DAD method was applied according to the Food Code. Malachite green levels above the quantification limit of the LC-MS/MS were determined 18.5% (37) but just 1 fish was shown to contain malachite green by HPLC-DAD. Of 83 domestic fish, 21 fish were detected malachite green (25.3%). Of 117 fish from China, just 16 fish were detected malachite green (13.4%). In detection rate by species carp (35.0%), Crucian carp (30.4%), cat fish (28.0%), Korean bull head (23.8%), snake head (20.0%), eel (10.5%) and loach (7.8%) were in order. Especially, fish collected at summer were shown to contain malachite green frequently; the detection rate was 54.8%.

A Study on Leaching Characteristics of $Cr^{6+}$ in Cement Grout Materials (시멘트 그라우트재에서 $Cr^{6+}$용출특성에 관한 연구)

  • 김동우;이재영;천병식
    • Journal of Soil and Groundwater Environment
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    • 제8권2호
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    • pp.62-69
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    • 2003
  • The aim of research is the evaluation of the $Cr^{6+}$ emission features of the liquid injection through emission experiments in varying conditions, based on a field-mixing ratio. The results showed that the content of $Cr^{6+}$ content in cement measured had an Ordinary Potland Cement (OPC) of 25.3 mg/kg, which constitute the largest portion among the other materials. Likewise, the emission experiment of homo-gel and sand-gel generally satisfied the standard of KSLT (Korea Standard Leaching Test) in waste of 1.5 mg/L, but in case of the standard of KSLT in soil the emission of OPC $Cr^{6+}$ of 4.85 mg/kg. These conditions is a little exceeded the criteria in the ‘Ga’ area in terms of Korea Soil Environmental Preservation Law. In addition, results generated by the mock-up injection facilities revealed that $Cr^{6+}$ emission increased as Water/Cement and injection pressure increased. At injection pressure higher than 4 kg/㎤, $Cr^{6+}$ emission exceeded the water preservation standard of 0.5 mg/L. Similarly, a pattern experiment of C $r^{6+}$ emission according to pH was conducted, in order to evaluate the $Cr^{6+}$ emission features of grout materials in leachate below pH 5 such as pH 4 acid rain or landfill. Results show that $Cr^{6+}$ emission dramatically increased in high acidic or basic state. It indicates that $Cr^{6+}$ emission will probably increase in an environment where grout materials are injected. On the other hand, concentration of leachate was determined in areas where grout materials are used. The results show that the concentration of emission in an ultra purity condition does not manifest intensity, and is affected in the OPC>MC>SC order. It means that the pollutants or $Cr^{6+}$ emission increases with decreasing concentration. As such, $Cr^{6+}$ emission will probably exceed the countermeasure criteria according to the types of gout materials. Similarly, high pressure or injection will cause increased $Cr^{6+}$ emission. Therefore, the selection of materials or mixing ratio should be considered in general as well as according to specific industries, based on the strength and pH of $Cr^{6+}$ emission.

Changes in Weed Occurrence and Dominance Influenced by Seeding Dates in Water Seeded Rice Paddy under No-tillage Condition (벼 무경운(無耕耘) 담수표면산파재배시(湛水表面散播栽培時) 파종시기(播種時期)에 따른 잡초(雜草) 발생양상(發生樣相) 및 우점도(優點度) 변이(變異))

  • Kwon, O.D.;Guh, J.O.;Shin, H.R.;Park, T.D.
    • Korean Journal of Weed Science
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    • 제18권3호
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    • pp.179-185
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    • 1998
  • This study was conducted to investigate changes in weed occurrence and dominance as affected by seeding dates in water seeded rice paddy under field following two years of no-tillage condition. The pre-emergence weeds in no-tillage paddy were controlled by glyphosate application at 7 days before seeding. The rice seeds were seeded on April 20, May 10 and May 30, respectively with 40kg/ha of seeding rate. The weed species in the paddy occurred included three species (Echinochloa cursgalli, Aneilma keisak, Ottelia alismoides) of annual weed, one species (Alopecurus aequalis) of biennial weed and five species (Eleocharis kuroguwai, Leersia japonica, Sagittaria pygmaea, Sagittaria trifolia, Potamogeton distinctus) of perennial weed respectively. Aneilma keisak was found to be dorminant on April 20 and May 10 but Eleocharis kuroguwai on May 30 based on number of weeds. The number and dry weight of weeds occurred were higher on May 10 as compared to in other seeding dates, while proportion of perennial weeds increased as the seeding date was delayed. In particular, weed dorminance varied marketly with seeding date. The Simpson's indices were 0.736 on April 20, 0.261 on May 10 and 0.281 on May 30, respectively.

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Bone Marrow Scintigraphy with Antigranulocyte Antibody in Multiple Myeloma: Comparison with Simple Radiography and Bone Scintigraphy (항과립구 항체 골수스캔을 이용한 다발성 골수종 병변의 평가: 단순골X-선점사 및 골스캔과의 비교)

  • Kim, Dong-Hwan;Lee, Jae-Tae;Baek, Jin-Ho;Jung, Jin-Tae;Hyun, Dong-Woo;Chun, Kyung-Ah;Lee, Young-Hak;Sohn, Sang-Kyun;Song, Hong-Seok;Lee, Kyu-Bo
    • The Korean Journal of Nuclear Medicine
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    • 제32권4호
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    • pp.354-364
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    • 1998
  • Purpose: Simple X-ray study and bone scan have limitations for early diagnosis of bone or bone marrow lesions in multiple myeloma. The purpose of this study was to evaluate the diagnostic usefulness of bone marrow immunoscintigraphy using anti-granulocyte monoclonal antibody for the evaluation of bone involvement in multiple myeloma. Materials and Methods: In 22 patients (Male: 15, Female: 7) with multiple myeloma, we performed whole-body immunoscintigraphy using $^{99m}Tc$-labelled antigranulocyte antibody (BW 250/183, Scintimum $Granulozyt^{(R)}$ CIS, France) and compared the findings with those of simple bone radiography and $^{99m}Tc$-MDP bone scan. Abnormal findings in bone marrow scintigraphy were, considered to be present in case of expansion of peripheral bone marrow or focal photon defect in axial bones. Results: Marrow expansion was noted in 15 of 22 patients (68%). Focal photon defects were found in 18 patients (82%). While one (33%) of 3 patients with Stage II disease showed focal defects in bone marrow scan, abnormal focal defects were observed in 17 of 19 (90%) patients with Stage III. Among 124 focal abnormal sites which were observed in bone marrow scan, bone scan or simple bone radiography, bone marrow scan detected 92 sites (74%), whereas 82 sites (66%) were observed in simple bone radiography(58 sites, 47%) or bone scan(40 sites, 32%). Fifty-one (41%) out of 124 bone lesions were detected by bone marrow scan only, and located mostly in thoracolumbar spine. Conclusion: Bone marrow scan using $^{99m}Tc$-labelled antigranulocyte antibody seems to be a more sensitive procedure for the detection of pathologic bone lesions than simple bone X-ray or bone scan in patients with multiple myeloma.

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Study on Waxy Corn X. Analysis on Botanical Characteristics, Physicochemical Properties Related to Table Qualities of the Developed Waxy Corn Hybrids (찰옥수수 연구 X. 육성된 찰옥수수 교잡종의 식물학적 특성 및 식미관련 이화학적 형질)

  • Lee, Moon-Sub;Bok, Tae-Gyu;Choi, Yun-Pyo;Hong, Bom-Young;Jo, Yang-Hee;Lee, Hee-Bong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • 제56권1호
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    • pp.8-13
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    • 2011
  • This study was carried out to compare botanical characteristics, physicochemical properties related to table quality and feed values and develop a new variety among 12 developed waxy com hybrids. These materials were produced in 2008 and cultivated in 2009 at Com Breeding and Genetics Farm of Coll. of Agri. & Life Sci., Chungnam Nat'l Univ. Botanical characteristics of used waxy com hybrids showed large difference among hybrids; stem height, ear height and ear length. In physical properties, range of kernel sugar content among used hybrids appeared 16.1 to 13.0brix(%). CNU08H-15, CNU08H-35 and CNU08H-h39 among these were highly appeared as 15 above and pericarp thickness of Yeonongchal was very thick as $46.0{\mu}m$, while CNU08H-39 among hybrids showed the thinnest as $23.0{\mu}m$ compared to other hybrids. Protein content as a indicator of table quality was the highest in Ilmichal among hybrids, while that of CNU08H-39 was the lowest, while amylopectin content was the highest as 94.5%, From experimental results, Daehakchal Gold 1, CNU08H-h121 and CNU08H-39 including check Yeonyoungchal were highly evaluated as new hybrid in thinner pericarp, high amylopectin and chewiness.

Size Dependent Analysis of Phytoplankton Community Structure during Low Water Temperature Periods in the Coastal Waters of East Sea, Korea (저수온기 동해연안의 식물플랑크톤 크기에 따른 군집구조)

  • Lee, Juyun;Chang, Man
    • Korean Journal of Environmental Biology
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    • 제32권3호
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    • pp.168-175
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    • 2014
  • In order to understand the phytoplankton community structure based on their cell size duringlow water temperature periods, we studied 10 stations in the East Sea, Korea on March, 2012. The minimum standing crops of total phytoplankton were $3.4{\times}10^6cells\;L^{-1}$ at the station 5. The maximum values were $7.6{\times}10^6cells\;L^{-1}$ at the station 8, which is two times the amount of the minimum. The carbon mass at the station 4 ($6.3{\times}10^8pg\;L^{-1}$) was more than forty times higher compared with station 5 ($0.08{\times}10^8pg\;L^{-1}$). From these results, we found a significant difference between standing crops and carbon mass which might have caused due to their differences in community structure and cell size. Therefore, we considered the types of plankton biomass to estimate the primary product in the specific location and/or time. The phytoplankton communities were classified in 3 types: microplankton (> $20{\mu}m$), nanoplankton (< $20{\mu}m$) and picoplankton (< $2{\mu}m$). In the case of picoplankton, various morphological types were observed during the study period. These various picoplankton species were further classified as S (spherical), SF (spherical&flagella), O (oval), OF (oval&flagella) or R (rod) type, and we analyzed their community structure based on these categories. The picoplankton was found to be the most dominant type at 8 stations and S type as the most popular. The picoplankton seems to be the significant organism in the marine ecology during low water temperature periods in the coastal waters of East Sea. Therefore, picoplankton \;-with scientific surveys can be considered as the database for their identification. In conclusion, we suggest that cell size of the phytoplankton would be the best criteria to accurately analyze their community structure and to reveal groups having more ecological influence.