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[ $Gd(DTPA)^{2-}$ ]-enhanced, and Quantitative MR Imaging in Articular Cartilage (관절연골의 $Gd(DTPA)^{2-}$-조영증강 및 정량적 자기공명영상에 대한 실험적 연구)

  • Eun Choong-Ki;Lee Yeong-Joon;Park Auh-Whan;Park Yeong-Mi;Bae Jae-Ik;Ryu Ji Hwa;Baik Dae-Il;Jung Soo-Jin;Lee Seon-Joo
    • Investigative Magnetic Resonance Imaging
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    • v.8 no.2
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    • pp.100-108
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    • 2004
  • Purpose : Early degeneration of articular cartilage is accompanied by a loss of glycosaminoglycan (GAG) and the consequent change of the integrity. The purpose of this study was to biochemically quantify the loss of GAG, and to evaluate the $Gd(DTPA)^{2-}$-enhanced, and T1, T2, rho relaxation map for detection of the early degeneration of cartilage. Materials and Methods : A cartilage-bone block in size of $8mm\;\times\;10mm$ was acquired from the patella in each of three pigs. Quantitative analysis of GAG of cartilage was performed at spectrophotometry by use of dimethylmethylene blue. Each of cartilage blocks was cultured in one of three different media: two different culture media (0.2 mg/ml trypsin solution, 1mM Gd $(DTPA)^{2-}$ mixed trypsin solution) and the control media (phosphate buffered saline (PBS)). The cartilage blocks were cultured for 5 hrs, during which MR images of the blocks were obtained at one hour interval (0 hr, 1 hr, 2 hr, 3 hr, 4 hr, 5 hr). And then, additional culture was done for 24 hrs and 48 hrs. Both T1-weighted image (TR/TE, 450/22 ms), and mixed-echo sequence (TR/TE, 760/21-168ms; 8 echoes) were obtained at all times using field of view 50 mm, slice thickness 2 mm, and matrix $256\times512$. The MRI data were analyzed with pixel-by-pixel comparisons. The cultured cartilage-bone blocks were microscopically observed using hematoxylin & eosin, toluidine blue, alcian blue, and trichrome stains. Results : At quantitation analysis, GAG concentration in the culture solutions was proportional to the culture durations. The T1-signal of the cartilage-bone block cultured in the $Gd(DTPA)^{2-}$ mixed solution was significantly higher ($42\%$ in average, p<0.05) than that of the cartilage-bone block cultured in the trypsin solution alone. The T1, T2, rho relaxation times of cultured tissue were not significantly correlated with culture duration (p>0.05). However the focal increase in T1 relaxation time at superficial and transitional layers of cartilage was seen in $Gd(DTPA)^{2-}$ mixed culture. Toluidine blue and alcian blue stains revealed multiple defects in whole thickness of the cartilage cultured in trypsin media. Conclusion : The quantitative analysis showed gradual loss of GAG proportional to the culture duration. Microimagings of cartilage with $Gd(DTPA)^{2-}$-enhancement, relaxation maps were available by pixel size of $97.9\times195\;{\mu}m$. Loss of GAG over time better demonstrated with $Gd(DTPA)^{2-}$-enhanced images than with T1, T2, rho relaxation maps. Therefore $Gd(DTPA)^{2-}$-enhanced T1-weighted image is superior for detection of early degeneration of cartilage.

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Studies on the Effects of Antler Extract in Osteoporosis-Induced Rats I. Effects of Antler Extract on Hormones, Ca, P and ALP Levels in Osteoporosis-Induced Rats (녹용 추출물 투여가 골다공증 유발 Rat 에 미치는 효과에 관한 연구 I. 녹용 추출물 투여가 골다공증 유발 Rat 의 혈청내 호르몬, Ca, P, ALP 수준에 미치는 영향)

  • Kim, S. K;Kim, S. W.;Kim, M. S.
    • Korean Journal of Animal Reproduction
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    • v.24 no.2
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    • pp.179-188
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    • 2000
  • The present study was carried out in order to investigate the effects of antler extract on hormone concentration, Ca, P and alkaline phosphatase (ALP) levels in ovariectomized rats. Rats were ovariectomized bilaterally and were fed up with Ca- and P-free diet in order to induce osteoporosis. Osteoporosis was determined by the extent of density of bone mineral and lowering the concentrations of serum Ca and P. Male or female antler extract were administrated for 5 weeks to elucidate the protective and therapeutic effects for osteoporosis. The serum concentrations of estradiol, progesterone, calcitonin, osteocalcin, Ca and P, and the activities of ALP of ovariectomized rats were examined for 5 weeks. 1. After administration of female or male antler extract to osteoporosis-induced rats at the doses of 625 mg/kg and 1,250 mg/kg, respectively, the levels of the serum estradiol of the ovariectomized rat significantly decreased from 40.50$\pm$3.34 pg/$m\ell$ to 20.80$\pm$1.86 pg/$m\ell$ for 5 weeks, the levels of serum estradiol were a signigicant lower than those of control group (49.50$\pm$2.70~50.80$\pm$3.l3 pg/$m\ell$). 2. After administration of female or male antler extract to osteoporosis-induced rats at the doses of 625 mg/kg and 1,250 mg/kg, respectively, the levels of serum progesterone were didn't show significant differences. 3. After administration of female or male antler extract to osteoporosis-induced rats at the doses of 625 mg/kg and 1,250 mg/kg, respectively, the levels of serum calcitonin were a little higher than those of control group (0.64$\pm$0.03 ~0.68$\pm$0.04 pg/$m\ell$). 4. After administration of female or male antler extract to osteoporosis-induced rats at the doses of 625 mg/kg and 1,250 mg/kg, respectively, the levels of serum osteocalcin were little higher than those of control groups (0.28$\pm$0.02~0.31$\pm$0.02 ng/$m\ell$). In addition, the levels of serum osteocalcin of female antler extract administered group were little higher than those of male antler extract administered group. 5. The levels of serum Ca and P in osteoporosisinduced rats, administered with male or female antler extract, were little higher than those of control group. However, the levels of serum Ca and P in ovariectomized rats were significantly higher than those of control group (p<0.05). 6. After administration of female or male antler extract to osteoporosis-induced rats, the activities of serum ALP increased compared with those of normal control group. There were significant differences between the serum ALP activities of FA 1,250 and 625 groups (p<0.05). These findings suggest a possible protective and therapeutic effects of female or male antler extract against bone loss in ovariectomized rats, associated with a significant increase of serum estradiol level.

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Decomposition Characteristics of Fungicides(Benomyl) using a Design of Experiment(DOE) in an E-beam Process and Acute Toxicity Assessment (전자빔 공정에서 실험계획법을 이용한 살균제 Benomyl의 제거특성 및 독성평가)

  • Yu, Seung-Ho;Cho, Il-Hyoung;Chang, Soon-Woong;Lee, Si-Jin;Chun, Suk-Young;Kim, Han-Lae
    • Journal of Korean Society of Environmental Engineers
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    • v.30 no.9
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    • pp.955-960
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    • 2008
  • We investigated and estimated at the characteristics of decomposition and mineralization of benomyl using a design of experiment(DOE) based on the general factorial design in an E-beam process, and also the main factors(variables) with benomyl concentration(X$_1$) and E-beam irradiation(X$_2$) which consisted of 5 levels in each factor was set up to estimate the prediction model and the optimization conditions. At frist, the benomyl in all treatment combinations except 17 and 18 trials was almost degraded and the difference in the decomposition of benomyl in the 3 blocks was not significant(p > 0.05, one-way ANOVA). However, the % of benomyl mineralization was 46%(block 1), 36.7%(block 2) and 22%(block 3) and showed the significant difference of the % that between each block(p < 0.05). The linear regression equations of benomyl mineralization in each block were also estimated as followed; block 1(Y$_1$ = 0.024X$_1$ + 34.1(R$^2$ = 0.929)), block 2(Y$_2$ = 0.026X$_2$ + 23.1(R$^2$ = 0.976)) and block 3(Y$_3$ = 0.034X$_3$ + 6.2(R$^2$ = 0.98)). The normality of benomyl mineralization obtained from Anderson-Darling test in all treatment conditions was satisfied(p > 0.05). The results of prediction model and optimization point using the canonical analysis in order to obtain the optimal operation conditions were Y = 39.96 - 9.36X$_1$ + 0.03X$_2$ - 10.67X$_1{^2}$ - 0.001X$_2{^2}$ + 0.011X$_1$X$_2$(R$^2$ = 96.3%, Adjusted R$^2$ = 94.8%) and 57.3% at 0.55 mg/L and 950 Gy, respectively. A Microtox test using V. fischeri showed that the toxicity, expressed as the inhibition(%), was reduced almost completely after an E-beam irradiation, whereas the inhibition(%) for 0.5 mg/L, 1 mg/L and 1.5 mg/L was 10.25%, 20.14% and 26.2% in the initial reactions in the absence of an E-beam illumination.

Research on the Methods and Proper Provisions for Rotational Irrigation (윤환관개방법과 적정시설 연구)

  • 유한열
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.13 no.1
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    • pp.2191-2205
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    • 1971
  • In this research, Nong-rim No. 6 was adopted as a test variety of rice. Rice seedlings were transplanted on June 14, 1970. Roots were settled into soil on June 20 and a total number of days irrigated of $21cm{\times}21cm$ and an area of $9.9m^2$ for a test plot were accepted, planting 70 stumps of rice in a test plot. The soil in test plots are classified by soil test as oam, and its chemical contents are as shown in Table 3. Irrigation water was secured by pumping from the Sudun stream that originates at the Suho reservoir. Accordingly, the qualities of irrigation. water are considered to be the same as those of water stored in the Suho reservoir. There were 54 days of intermittent rainfalls in total during the whole 110-day period of irrigation. As a result, it is likely that the growth of rice plants was influenced by rainfall at a comparatively great degree. In order to measure the amounts of water consumption, infiltrometers, measuring devices for the decreases of water depths and lycimeters were provided. As a result of measurements, an average daily rate of infiltration was observed to be 14mm/day. It is expected from this research that the effect of increased yield will be secured by supplying optimum amounts of water for irrigation on proper times, and that the amounts of water consumption for irrigation can be saved by applying suitable irrigation methods. The test results obtained are summarized as follows: 1. Yields produced in the test plots of continuous irrigation are lower than those in the test plots of rotational irrigation, i.e., yields produced at the test plots irrigatied once in a period of 8 days are higher by 27% in average than those produced at test plots of continuous irrigation. 2. The amounts of irrigation water for test plots, which have a clay layer of 9cm in thickness and vynil diaphragm without holes, are saved by about 52% in comparison with ordinary test plots. 3. Ears are sprouted 5 days earlier at continuous irrigation plots as compared with other test plots. 4. It seems that there are growing stages of rice plants such as those of forming and sprouting of ears, in which the amounts of irrigation water are consumed more in comparison with the other stages. Therefore, it may be possible to increase of decrease the amount of irrigation water, according to the growing stage of rice plant, so as to save irrigation water.

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Studies on the Effects of Various Methods of Rotation Irrigation System Affecting on The Growth, Yield of Rice Plants and Its Optimum Facilities (수환관개방법의 차이가 수도생육 및 수량에 미치는 영향과 그 적정시설에 관한 연구)

  • 이창구
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.12 no.2
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    • pp.1937-1947
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    • 1970
  • This experiment was conducted, making use of the 'NONG-RIM No, 6' a recommended variety of rice plant for the year of 1969. Main purpose of the experiment are to explore possibilities of; a) ways and means of saving irrigation water and, b) overcoming drought at the same time so that an increaded yield in rice production could be resulted in Specifically, it was tried to determine the effects of the Rotation Irrigation method combined with differentiated thickess of Lining upon the growth and Yield of rice production. Some of the major finding are summarized in the follows. 1) The Different thicknesses show a significant relationship with the weight of 1000 grains. In the case of 3cm Lined plot, the grain weight is 39.0 Grams, the heaviest. Next in order is 6 cm lined plnt, 5 day control plot, 6 day control plot. 2) In rice yield, it is found that there is a considerably moderate signicant relationship with both the different thickness of lining and the number of irrgation, as shown in the table No,7. 3) There is little or no difference among different plot in terms of; a) physical and chemical properties of soil, b) quality of irrgation water, c) climatic condition, and rainfalls. 4) It is found that there is no significant relationship between differences in the method of rotation irrgation and the number of ears per hill because of too much rainydays and low temperature during irrigation season. 5) In uyny1-treated plots, it is shown that there is on difference among different plots, but the irrigation water requirement saved as much as 1/2 to actual irrigation water compare to uncontroled plot. 6) The irrigation water requirement for 48 days is saved as much 67% compared to uncontroled plot, the order are; the 9cm lined plot, the plot of vinyl with no hole, the plot with a hole of $1cm/m^2$ as shows in fig 15. 7) The rate of percolation of 40-30mm/day is decreased to 30-20/day. It is found that the decreasad rate of percolation due to vinyl-cutoff in footpath. 8) The growing condition was fine, and there was no found that decease and lageing as always submerged plot. 9) It is found that it must be constructed irrigation and drainage system, inlet and outlet perpect, respectly, of which could be irrigation water saved and would be inereased the irrigation water temperature.

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Experimental Study of Flip-Bucket Type Hydraulic Energy Dissipator on Steep slope Channel (긴구배수로 감세공의 Filp Bucket형 이용연구)

  • 김영배
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.13 no.1
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    • pp.2206-2217
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    • 1971
  • Spillway and discharge channel of reservoirs require the Control of Large volume of water under high pressure. The energies at the downstream end of spillway or discharge channel are tremendous. Therefore, Some means of expending the energy of the high-velocity flow is required to prevent scour of the riverbed, minimize erosion, and prevent undermining structures or dam it self. This may be accomplished by Constructing an energy dissipator at the downstream end of spillway or discharge channel disigned to dissipated the excessive energy and establish safe flow Condition in the outlet channel. There are many types of energy dissipators, stilling basins are the most familar energy dissipator. In the stilling basin, most energies are dissipated by hydraulic jump. stilling basins have some length to cover hydraulic jump length. So stilling basins require much concrete works and high construction cost. Flip bucket type energy dissipators require less construction cost. If the streambed is composed of firm rock and it is certain that the scour will not progress upstream to the extent that the safety of the structure might be endangered, flip backet type energy dissipators are the most recommendable one. Following items are tested and studied with bucket radius, $R=7h_2$,(medium of $4h_2{\geqq}R{\geqq}10h_2$). 1. Allowable upstream channel slop of bucket. 2. Adequate bucket lip angle for good performance of flip bucket. Also followings are reviwed. 1. Scour by jet flow. 2. Negative pressure distribution and air movement below nappe flow. From the test and study, following results were obtained. 1. Upstream channel slope of bucket (S=H/L) should be 0.25<H/L<0.75 for good performance of flip bucket. 2. Adequated lip angle $30^{\circ}{\sim}40^{\circ}$ are more reliable than $20^{\circ}{\sim}30^{\circ}$ for the safety of structures.

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Studies on the Amylase Production by Bacteria (세균(細菌)에 의(依)한 Amylase생산(生産)에 관한 연구(硏究))

  • Park, Yoon-Joong
    • Applied Biological Chemistry
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    • v.13 no.2
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    • pp.153-170
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    • 1970
  • 1. Isolation and identification of amylase-producing bacteria. The powerful strain A-12 and S-8 were respectively isolated from air and soil after screening a large number of amylase-producing bacteria. Their bacterial characteristics have been investigated and it has been found that all characteristics of strain A-12 and S-8 are similar to Bac. subtilis of Bergey's manual except for the acid formation from a few carbohydrates and the citrate utilization, i.e., the strain A-12 shows negative in the citrate utilization, and the acid formation from arabinose and xylose, S-8 shows negative in the acid formation from xylose. 2. Amylase production by Liquid cultures with solid materials. Several conditions for amylase production by strain A-12 in stationary cultures have been studied. The results obtained are as follows. (1) The optimum conditions are:temperature $35^{\circ}C$, initial pH 6.5 to 7.0 and incubation time 3 to 4 days. (2) The amylase production is not affected by the preservation period of the stock cultures. (3) Among the various solid material, the defatted soy bean is found to be the best for t1e amylase production. However, the alkali treatment of the defatted soy bean gives no effect contrary to the cage of defatted rape seed. The addition of soluble starch to the alkali extract of defatted soy bean shows the increased amylase production. (4) Up to 1% addition of ethanol to carbon dificient media gives the improved amylase production, whereas the above effect is not found in the case of carbon rich media. (5) The amylase production can be increased 2.5 times when 10% of defatted soy bean is admixed to cheaply available wheat bran. (6) The excellent effect is found for amylase production when 20% of wheat bran is admixed to defatted dry milk which is a poor medium. The activity is found to be $D^{40^{\circ}}_{30'}$ 7,000(L.S.V. 1,800) in 10% medium. (7) No significant effect is observed due to the addition of various inorganic salts. 3. Amylase production by solid cultures. Several conditions for amylase production by strain A-12 in wheat bran cultures have been studied and the results obtained are as follows. (1) The optimum conditions: are temperature $33^{\circ}C$, incubation lime 2 days, water content added 150 to 175% and the thickness of the medium 1.5cm, The activity is found to be $D^{40^{\circ}}_{30'}$ 36,000(L.S.V. 15,000) (2) No significant effect is found in the case of the additions of various organic and inorganic substances.

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PROPAGATION OF THE BLUE CRAB, PORTUNUS TRITUBERCULATUS (MIERS) (꽃게 Portunus trituberculatus (MIERS)의 종묘 생산에 관한 연구)

  • PYEN Choong-Kyu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.3 no.3
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    • pp.187-198
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    • 1970
  • The author succeeded in rearing the young blue crab from the first stage of zoe ato the true crab shape, and during this time he observed their growth and metamorphosis. The relationships between the number of eggs carried by female crabs (E) and the carapace width (C) and body weight (W) are shown as follows: E= 27.9049C-281.8155, E=0.5682 W-116.4606. There are five zoeal stages and a megalopa in the complete larval development of the blue crab. Water temperature in rearing aquaria ranged from 21.4 to $25.2^{\circ}C$. The duration of each zoeal stage was two days on the average. After the fifth moulting, the zoea becomes megalopa and 5 to 6 days later the megalopa moults and develops into the first stage of adult crab shape. The carapace width of megalopa measured about 1.70 mm and the carapace length, from the tip of the rostrum to the posterior dorsal margin of the carapace, was about 2.78 mm on the average. The carapace width and length of the first crab, 18 days after hatching, measured about 4.48 mm and 2.62 mm respectively. After two days, the first crab moulted and grew into the second crab with about 6.47 mm in carapace width and 4.66 mm in carapace length. The larval rearing in the outdoor tank shelved better results than in the indoor aquarium. The highest mortality occurred when the first stage of zoea moulted into the second stage. Percentage of crabs which survived, from the first crab to the ninth crab stages, was about $55\%$. The relationships between rearing days (D) and the carapace width (C), carapace length (L) and body weight (W) of the crab stages during 40 days of rearing are shown as follows. Carapace width, Indoor: C=1.1250D+1.7227 Outdoor C=1.3465D -0.2449 Carapace length, Indoor: L=0.6654D+1.6712 Outdoor: L=0.7893D+0.6919 Body Weight, Outdoor: $$W=1.15e^{0.12423D}$$ Indoor: $$W=6.759\times10^{-2}D^{1.2598}$$ (9-19 day old crabs) Outdoor: $$W=4.136\times10^{-2}D^{1.6024}$$ (21-40 day old crabs) During the crab stage, the following relationships between the number of moulting times and the carapace width (C), carapace length (L) and body weight (W) were found as follows: $$C=5.2e^{0.28119N}$$ $$L=3.65e^{0.26372N}$$ $$W= 0.14e^{0.7037N}$$ The relationships between the carapace length (L) and the carapace width (C) and body weight (W) of the crab stages are shown as follows: Carapace length, mm Formula 2.62-27.17 L=1.6864C-1.0387 7.47-18.53 $$W=9.367\times10^{-5}C^{3.5567}$$ 22.11-27.17 $$W=3.406\times10^{-5}C{3.8571}$$

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Seedling - Emergence of Rice, Weedy Rice, and Echinochloa species Sown before Wintering and in the Early Spring (월동전(越冬前) 초춘(初春)에 파종(播種)한 재배(栽培)벼, 잡초성(雜草性)벼 및 피의 출현특성(出現特性))

  • Kwon, Y.W.;Lee, B.W.;Kim, D.S.
    • Korean Journal of Weed Science
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    • v.16 no.2
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    • pp.88-99
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    • 1996
  • In recent years dry direct-seeding of rice has been encouraged by the government and increasingly practiced by farmers in Korea. This has been bringing up an increased occurrence of weedy rites. Some farmers in the southern region dare to sow the rice before winter after harvest, while most farmers wish to sow as early as possible in the spring to secure the growing period, and to disperse the intensive labor in early May. The purpose of this study was to determine the feasibility of moving the sowing of rice to an earlier date under dry direct-seeding, and to elucidate the nature of emergence of an old strain of rice, weedy rites, and barnyardgrasses tinder this farming practice and their adaptive competence over present cultivate. The presently recommended rice cultivar, Dongjinbyo and an old rice strain, Dadajo which prevailed in early 1900s, almost could not emerge from soil deeper than 6cm and could emerge to only 5.3% at best from 1cm deep loamy soil field when the seeds were sown on Nov. 28. However, two strains of weedy rites being weedy for over 200 years emerged by 17.0 to 63.0% from the loamy and sandy clay loam field 1 to 6cm deep. Emergence of the weedy rites was greater in the loamy soil and at a shallow depth, and negligible from the soil depth of 9cm. Barnyardgrasses sown on Nov. 28 emerged by 13.4 to 51 % from the 1 to 3cm deep loamy soil, and 8.6 to 46.7% from the 1cm deep sandy clay loam. Echinochloa crus-galli var. crus-galli emerged more than var. praticola, and var. oryzicola least. Most of the non-emerged barnyardgrasses seem to have entered secondary dormancy. Seeding rice a month earlier than the season lowered the emergence of Dongjinbyo by ca. 10, 18, and 26%, respectively at 1, 3, and 6cm soil depths, indicating that moving the seeding date a month earlier is impractical. The old strain, Dadajo sown in the soil at a depth of 6cm responded similarly. However, the strain has shown a significantly higher ability in emergence from 9cm deep soil. Weedy rices sown a month earlier A month earlier sown weedy rices have shown very similar emergence rates at various soil depths to those sown on May 1. Barnyardgrasses have also shown similar emergence rates when sown between April 3 and May 1. Like barnyardgrasses, the old strain and weedy rices apparantly posessed a greater adaptability to emerge under lower temperatures, and from deeper soil ; Dongjinbyo${\leq}$ Echinochloa species in that order. However, emergence- speed under lower temperature(sown on April 3) was faster in the order of weedy rice

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진도의 담수산 물벼룩류와 요각류의 출현특성에 관한 생태학적 연구

  • Yoon, Seong-Myeong;Chang, Cheon-Young;Kim, Won
    • Animal Systematics, Evolution and Diversity
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    • v.11 no.1
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    • pp.39-64
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    • 1995
  • A faunistic and ecological study on the occurrence of freshwater cladocerans and copepods was accomplished from Chindo, South Korea. Collections were made from total 35 stations, comprising the various freshwater habitats like reservoirs, streams, swamps, bogs, ricefields, ditch, pond, and spring during the periods of July 23-25, and November 1-3 in 1994. Twenty seven cladoceran species of 17 genera of 6 families in 2 orders, and 28 copepod species of 21 genera of 6 families in 3 orders were collected during this research period, of which Daphnia obtusa Kurz and Elaphoidella bidens (Schmeil) are newly recorded from Korea. In reservoirs, Diaphanosoma sp. and Thermocyclops taihokuensis were dominant in July, and then succeeded by Bosmina longirostris and Cyclops vicinus vicinus in November. Thermocyclops crassus co-occurred with 7: taihokuensis at both seasons, was frequent in November after T. taihokuensis precipitately decreased. In other stagnant waters, 7: taihokuensis and Moina weismanni were dominant at ponds in July and in November, respectively. At ricefields in July Moina macrocopa and T. taihokuensis were dominant, but in November M. macrocopa and Paracyclops fimbriatus were. At streams, cladocerans were relatively rare, but became more rich in November. The representative cladoceran species were Bosmina longirostris as a plankton, and Chydorus sphaericus as a epibenthic species. Concerning copepods, nearly all the stations of streams except a few ones adjacent to seashore showed the similiar species constitutions, of which E. serrulatus and M, pehpeiensis were most frequent and abundant. At a mountain streamlet and a spring, the occurrence of Alona sp., Attheyella byblis Chang and Kim, 1992 and A. tetraspinosa Chang, 1993 is quite interesting and deserved much attention in the taxonomical point of view. Seventeen major cladocerans and copepods from lentic habitats and 13 major cladocerans and copepods from lotic habitatats were clustered using average taxonomic distance and UPGMA to infer the co-occurrence relations among species. As for lentic habitats, two large phena were appeared at first. The one phenon consisted of Diaphanosoma sp. and T taihokuensis, and showed its predominancy over the various habitats and its dominancy was rapidly decreased in November. The other phenon frequently occurred rather in November, and subdivided into three subgroups. On the other hand, as for lotic habitats, 13 species were also grouped into 2 large phena. The first one comprised 4 species, which were dominant and highly frequent at nearly all the lotic habitats, and subdivided into three subgroups according to their seasonal fluctuation types. The second one was also subdivided into three phena, the first of which comprised only one species, Microcyclops varicans, and occurred at most of the stations along stream with steadiness through the research period; the second phenon, Chydorus sphaericus, occurred much frequently in November; the last phenon included a few heterogenous subgroups.

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