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Variation of rachis branches in rice varieties with different maturing types by various planting times. (벼 작기이동에 따른 조만성별 수상의 착생변이)

  • 심재성
    • Korean Journal of Plant Resources
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    • v.9 no.3
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    • pp.285-290
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    • 1996
  • This experiment was conducted to investigate the variation of adhering primary and secondary rachis branches of panicle in three ecotypes at National Honam Agricultural Experiment Station in 1993. Three ecotypes. Odaebyeo and Sinunbongbyeo as early-maturing type, Cheongmyeongbyeo and Changanbyeo as medium, and Dongjinbyeo and Mangeumbyeo as late-maturing type were used. The treatment were 5 planting times from May 5 to 5 July by 15 day intervals. The number of primary rachis branch in early maturing type recorded high in between May 5 and 20 May as early transplanting. Medium and late-maturing type, however, was found to be have more primary rachis branches at the late time of June 20 transplanting than at the optimum transplanting of Honam area. The number of secondary rachis branch was high between June 5 and 20 June regardless ecotypes. The rate of secondary rachis branch per primary rachis branch was increased with later transplanting time up to June 5, but showed no differences onwards. The number of grain in primary and secondary rachis branches were low in transplanting time of May 5 regardless ecotype but high in late transplanting time by July 5. Densinty of seed sets was found to be higher in late transplanting than in early transplating;early-maturing type showed high in July 5 and 20 June in medium-late maturing type respectively.

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Movement of Cold Water Mass in the Northern East China Sea in Summer (하계 동중국해 북부 해역에서 저층 냉수괴의 거동)

  • Jang, Sung-Tae;Lee, Jae-Hak;Kim, Cheol-Ho;Jang, Chan-Joo;Jang, Young-Suk
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.16 no.1
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    • pp.1-13
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    • 2011
  • The Yellow Sea Cold Water (YSCW) is formed by cold and dry wind in the previous winter, and is known to spread southward along the central trough of the Yellow Sea in summer. Water characteristics of the YSCW and its movement in the northern East China Sea (ECS) are investigated by analyzing CTD (conductivity-Temperature-Depth) data collected from summertime hydrographic surveys between 2003 and 2009. By water mass analysis, we newly define the North Western Cold Water (NWCW) as a cold water mass observed in the study area. It is characterized by temperature below $13.2^{\circ}C$, salinity of 32.6~33.7 psu, and density (${\sigma}_t$) of 24.7~25.5. The NWCW appears to flow southward at about a speed less than 2 cm/s according to the geostrophic calculation. The newly defined NWCW shows an interannual variation in the range of temperature and occupied area, which is in close relation with the sea surface temperature (SST) over the Yellow Sea and the East China Sea in the previous winter season. The winter SST is determined by winter air temperature, which shows a high correlation with the winter-mean Arctic Oscillation (AO) index. The negative winter-mean AO causes the low winter SST over the Yellow Sea and the East China Sea, resulting in the summertime expansion and lower temperature of the NWCW in the study area. This study shows a dynamic relation among the winter-mean AO index, SST, and NWCW, which helps to predict the movement of NWCW in the northern ECS in summer.

Diel and Tidal Distributions of the Sand-burrowing Mysids Archaeomysis kokuboi and Acanthomysis nakazatoi on a Sandy Shore Surf Zone of Yongil Bay, Eastern Korea, in Relation to Growth Stages (동해 영일만 쇄파대에 서식하는 곤쟁이 Archaeomysis kokuboi와 Acanthomysis nakazatoi의 성장단계에 따른 주야 및 조석간 분포)

  • Jo, Soo-Gun;Kim, Chung-A;Suh, Hae-Lip
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.17 no.2
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    • pp.112-119
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    • 2012
  • This study investigated the diel and tidal distributions of the two mysids, Archaeomysis kokuboi and Acanthomysis nakazatoi, in relation to their growth stages in the sandy surf zone of Yongil Bay, located on the southeastern part of Korean Peninsula. Sampling was conducted with a sledge net at every two hours for almost 24 hours at three sites: water edge, water surface and sand bottom both in 1-m deep water areas. The abundance of Archaeomysis kokuboi juveniles was too low to count both in day and night samples. While there was no difference in immature A. kokuboi abundance between day and night in the bottom or water edge, that at the water surface was significantly higher at night than daytime. The abundance of A. kokuboi adults, especially of males, in the bottom was significantly higher in daytime than night and no individuals appeared to the water surface either day or night. In comparison, the abundance of Acanthomysis nakazatoi juveniles between day and night did not differ significantly at all the three sites, with the highest number being distributed in the bottom. The abundance of immatures between day and night also did not differ significantly and no individuals appeared to the water surface either day or night. The abundance of A. nakazatoi adults, especially females, in the bottom was significantly higher at night than daytime and there was no significant difference in abundance between day and night in the other sites. There was also no significant difference in abundances of the two species between ebb and flood tides, except for A. kokuboi immatures which appeared significantly more during the ebb tides at the water surface. Overall, the distribution of the two sympatric species, A. kokuboi and A. nakazatoi, was not the same in the sandy surf zone. Its difference seems to depend on their stages of growth, and the change in their abundance may be influenced more by diurnal rhythms than tidal effects. The population density of A. nakazatoi in the sandy surf zone was much higher than that of A. kokuboi, and relatively higher densities in all growth stages of the former were found in the sandy bottom ranging from juveniles to adults. These results indicate that A. nakazatoi has exceedingly better ability of sand burrowing even from the juvenile stage, and thus is an ecologically better adapted species in the sandy surf zone than another sympatric species, A. kokuboi.

Effect of Nandrolone Decanoate on Disuse Muscle Atrophy and Bone Beating in Dogs (개에서 불용성 근위축과 골절 치유에 대한 Nandrolone decanoate의 효과)

  • Yun Seong-jin;Lim Ji-hey;Rahman Md. Mizanur;Byeon Ye-eun;Kim Wan-hee;Kweon Oh-kyeong
    • Journal of Veterinary Clinics
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    • v.22 no.4
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    • pp.336-341
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    • 2005
  • Anabolic steroid compounds are widely used for the increase of muscle mass, density of bone and athletic ability. The present study conducted to evaluate the effects of nandrolone decanoate (ND), one of the anabolic steroid compounds, on disuse muscle atrophy and healing process of bone in dogs. Twenty physically healthy dogs of both sexes were used in this experiment and divided into three groups: group A (control), group B (low dose M-1.5 mg/kg) and group C (high dose ND-7.5 mg/kg). One-mm strip of full thickness bone was excised from the radius below the pronator teres muscle for the artificial fracture and then the fractured ends were fixed in apposition with bone plate leaving 1mm gap, and finally immobilized externally by Robert John's bandage for 4 weeks. ND was administered intramuscularly once a week far 8 weeks. Body weight, muscle mass change and fracture gap of the bone were evaluated immediately after surgery, and 2, 4, and 8 weeks after surgery. The rates of muscle mass change 8 weeks after surgery were $-2.75\pm0.16\%,\;1.68\pm0.11\%\;and\;1.74\pm0.48\%$ in groups A, B and C, respectively. The significant increase (p<0.05) of muscle mass increments were found in the treated groups. The fibrous connective tissue layer in the fracture gaps of the treated groups increased more than the control, especially in the group C at 4th week. More dense fibrous connective tissue were found in the treated groups at 8th week. Collectively, our results suggested that ND was an effective anabolic agent for the immobilized disuse muscle and bone healing.

Development of Lotus Root Bugak with Plasma Lipid Reduction Capacity by Addition of Opuntia ficus-indica var. saboten or Green Tea as a Coloring Agent (백년초 및 녹차 가루 첨가 연근 부각의 지질저하 기능성)

  • Kim, Mijeong;Hong, Sun Hee;Chung, Lana;Choe, Eunok;Song, Yeong-Ok
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.3
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    • pp.333-340
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    • 2014
  • The purpose of this study was to develop functional lotus root bugak with plasma lipid reduction capacity by controlling the color of batter used for bugak preparation. Lotus root, nearly colorless, was selected to observe color effects. Gardeniae fructus (GF), Opuntia ficus-indica var. saboten (OF), and green tea (GT), which are colored yellow, red, and green, respectively, were used as coloring agents. Fermented glutinous rice was prepared naturally during winter season by placing glutinous rice and water (1:2, w/w) together in a crock pot for 7 days. Coloring materials (10%, w/w) were blended with glue made from fermented glutinous rice flour to prepare the batter. Cooked lotus root was then mixed with a 1.1-fold amount of batter (w/w) and dried at room temperature. Lotus root bugak (LRB) is pan-fried with un-roasted sesame oil, which is traditionally used as frying oil in Korea. Low-density lipoprotein receptor knockout ($LDLr^{-/-}$) mice (n=36) were fed an atherogenic diet (AD) containing various types of LRB (10 g%) for 10 weeks. Plasma triglyceride, total cholesterol, and LDL-C concentrations decreased significantly in mice fed LRB prepared with OF batter (OFB) and GT batter (GTB) (P<0.05). Protein expression levels of fatty acid synthase (FAS) and 3-hydroxyl-3-methylglutaryl coenzyme A reductase (HMGCR) in the OFB and GTB groups were suppressed compared with the LRB group (P<0.05). In accordance with the results on FAS and HMGCR expression, sterol regulatory element binding protein-I and II (SREBP-I and II), which are responsible for the regulation of FAS and HMGCR gene expression, respectively, were down-regulated compared to the LRB group (P<0.05). In conclusion, the plasma lipid reduction activities of OFB and GTB could be mediated through down-regulation of FAS and HMGCR mRNA expression via suppression of regulatory molecules, SREBP-I and II, in $LDLr^{-/-}$ mice.

Use of Real-Time PCR and Internal Standard Addition Method for Identifying Mixed Ratio of Chicken Meat in Sausages (Real-Time PCR과 Internal Standard Addition법을 이용한 돼지고기 소시지에 혼합된 닭고기의 정량)

  • Lee, Namrye;Joo, Jae-Young;Yeo, Yong-Heon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.9
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    • pp.1097-1105
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    • 2017
  • This study examined how much chicken meat was in sausage made with pork. Both real-time polymerase chain reaction (PCR) and internal standard addition were used. Fifty ng of chicken DNA was added to the sausages as an internal standard. The addition of standard DNA increased the amplification efficiency of PCR and confirmed the possibility of quantitative analysis. A QIAamp DNA Micro Kit was used to improve the DNA recovery and amplification efficiency. The density of template DNA and primer were suitable for $3.0{\sim}5.0{\mu}L$ and $0.5{\mu}L$, respectively. Each DNA of pig and chicken was diluted in 10-fold from steps 50 ng to 0.05 ng. The detection limit of both pig and chicken meat was more than 0.05 ng and the correlation coefficient of the standard curve was at least 0.98. The result of the quantitative analysis after heat treatment of 3 samples of pigs and chickens mixed at 70:30 showed a 5.7% difference (64.3:35.7) between the expected value and measured value. The quantitative value was changed by affecting the DNA according to the heat treatment ($70^{\circ}C$, 10 min). An analysis of the pork and chicken content in sausages showed that it was difficult to detect chicken meat and the quantitative value of DNA according to the Ct value was very low. On the other hand, when adding standard material (50 ng of chicken DNA) to the sausages, the Ct value decreased gradually with increasing chicken mixing ratio. Thus, the mixing ratio of chicken in sausages could be estimated.

Physio-Chemical Characteristics of Soil, Stream Sediment and Soil Water Contaminated by the Abandoned Coal Mine in Keumsan, Chungnam (충남(忠南) 금산(錦山) 폐탄광지역(廢炭鑛地域)의 토양(土壤), 하상퇴적물(河床堆積物) 및 토양수(土壤水)의 이화학적(理化學的) 특성(特性))

  • Min, Ell Sik;Kim, Myung Hee;Song, Suckhwan
    • Journal of Korean Society of Forest Science
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    • v.86 no.3
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    • pp.324-333
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    • 1997
  • The research has been made for the effects of the pollution by the abandoned coal mine drainage on the physical and chemical properties of soil, stream sediment and soil water. The soils overspreaded by the abandoned coal don't develop solum and the bulk density is $1.83g/m^3$, compared with $1.14-1.38g/m^3$ in the other forest soils. The soil pH range in coal bearing region ie, from 4.01 to 4.11 and non-coal bearing soil range is from 5.03 to 5.13. Heavy metals such as As, Cr, Ni, Mo and Ba of coal bearing soils and polluted stream sediments have larger concentration than those of non-coal content and non-polluted. Especially As and Mo concentrations are largely high in coal bearing. The relative ratios $K_2O/Na_2O$ of geochemical elements are higher in coal bearing soil and polluted stream sediments than those of non-coal bearing soils and non-polluted stream sediments as well as black shales of the Changri Formation. However, $MgO+Fe_2O_3+TiO_2/CaO+K_2O$ are the opposite trends, so that the ratios are lower in the polluted regions. The soil water pHs in the polluted regions are the strong acid(pH3.4-4.2) and buffer capacity of the polluted soil is low because canons such as $Na^+$, $K^+$, $Mg^{+2}$are leached by the acidification.

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Simulation and Measurement of Signal Intensity for Various Tissues near Bone Interface in 2D and 3D Neurological MR Images (2차원과 3차원 신경계 자기공명영상에서 뼈 주위에 있는 여러 조직의 신호세기 계산 및 측정)

  • Yoo, Done-Sik
    • Progress in Medical Physics
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    • v.10 no.1
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    • pp.33-40
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    • 1999
  • Purpose: To simulate and measure the signal intensity of various tissues near bone interface in 2D and 3D neurological MR images. Materials and Methods: In neurological proton density (PD) weighted images, every component in the head including cerebrospinal fluid (CSF), muscle and scalp, with the exception of bone, are visualised. It is possible to acquire images in 2D or 3D. A 2D fast spin-echo (FSE) sequence is chosen for the 2D acquisition and a 3D gradient-echo (GE) sequence is chosen for the 3D acquisition. To find out the signal intensities of CSF, muscle and fat (or scalp) for the 2D spin-echo(SE) and 3D gradient-echo (GE) imaging sequences, the theoretical signal intensities for 2D SE and 3D GE were calculated. For the 2D fast spin-echo (FSE) sequence, to produce the PD weighted image, long TR (4000 ms) and short TE$_{eff}$ (22 ms) were employed. For the 3D GE sequence, low flip angle (8$^{\circ}$) with short TR (35 ms) and short TE (3 ms) was used to produce the PD weighted contrast. Results: The 2D FSE sequence has CSF, muscle and scalp with superior image contrast and SNR of 39 - 57 while the 3D GE sequence has CSF, muscle and scalp with broadly similar image contrast and SNR of 26 - 33. SNR in the FSE image were better than those in the GE image and the skull edges appeared very clearly in the FSE image due to the edge enhancement effect in the FSE sequence. Furthermore, the contrast between CSF, muscle and scalp in the 2D FSE image was significantly better than in the 3D GE image, due to the strong signal intensities (or SNR) from CSF, muscle and scalp and enhanced edges of CSF. Conclusion: The signal intensity of various tissues near bone interface in neurological MR images has been simulated and measured. Both the simulation and imaging of the 2D SE and 3D GE sequences have CSF, fat and muscle with broadly similar image intensity and SNR's and have succeeded in getting all tissues about the same signal. However, in the 2D FSE sequence, image contrast between CSF, muscle and scalp was good and SNR was relatively high, imaging time was relatively short.

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Improved Device Performance Due to AlxGa1-xAs Barrier in Sub-monolayer Quantum Dot Infrared Photodetector

  • Han, Im Sik;Byun, Young-Jin;Lee, Yong Seok;Noh, Sam Kyu;Kang, Sangwoo;Kim, Jong Su;Kim, Jun Oh;Krishna, Sanjay;Ku, Zahyun;Urbas, Augustine;Lee, Sang Jun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.298-298
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    • 2014
  • Quantum dot infrared photodetectors (QDIPs) based on Stranski-Krastanov (SK) quantum dots (QDs) have been widely explored for improved device performance using various designs of heterostructures. However, one of the biggest limitations of this approach is the "pancake" shape of the dot, with a base of 20-30 nm and a height of 4-6 nm. This limits the 3D confinement in the quantum dot and reduces the ratio of normal incidence absorption to the off-axis absorption. One of the alternative growth modes to the formation of SK QDs is a sub-monolayer (SML) deposition technique, which can achieve a much higher density, smaller size, better uniformity, and has no wetting layer as compared to the SK growth mode. Due to the advantages of SML-QDs, the SML-QDIP design has attractive features such as increased normal incidence absorption, strong in-plane quantum confinement, and narrow spectral wavelength detection as compared with SK-DWELL. In this study, we report on the improved device performance of InAs/InGaAs SML-QDIP with different composition of $Al_xGa1-_xAs$ barrier. Two SML-QDIPs (x=0.07 for sample A and x=0.20 for sample B) are grown with the 4 stacks 0.3 ML InAs. It is investigated that sample A with a confinement-enhanced (CE) $Al_{0.22}Ga_{0.78}As$ barrier had a single peak at $7.8{\mu}m$ at 77 K. However, sample B with an $Al_{0.20}Ga_{0.80}As$ barrier had three peaks at (${\sim}3.5{\mu}m$, ${\sim}5{\mu}m$, ${\sim}7{\mu}m$) due to various quantum confined transitions. The measured peak responsivities (see Fig) are ~0.45 A/W (sample A, at $7.8{\mu}m$, $V_b=-0.4V$ bias) and ~1.3 A/W (sample B, at $7{\mu}m$, $V_b=-1.5V$ bias). At 77 K, sample A and B had a detectivity of $1.2{\times}10^{11}cm.Hz^{1/2}/W$ ($V_b=-0.4V$ bias) and $5.4{\times}10^{11}cm.Hz^{1/2}/W$ ($V_b=-1.5V$ bias), respectively. It is obvious that the higher $D^*$ of sample B (than sample A) is mainly due to the low dark current and high responsivity.

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Studies on the Fruiting Phase of Rape Under the Different Cultural Conditions

  • Kae, B.M.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.12
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    • pp.77-87
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    • 1972
  • The fruiting phase of rape under transplanting and direct-sowing conditions has been studied at Mokpo during the 2 years period from 1970 to 1971. Two varieties, Yudal and Miyuki were used in this study. The planting space and sowing time were also incorporated into this study. The results could be summarized as follows: 1. The plant tape of rape was nearly umbrella-shaped of all, but has changed to the laid elliptical-shaped, broadly ovate and spindle-shaped under different varieties and cultural conditions in the plant diagram(Fig. 2). 2. The length of the primary branches for each nodes had a tendency to the symmetric apical curve with the apex at the upper 10-12th node in the transplanting. but to the upper bias apical curve with the apex at the upper 5-7th node in the dense-sowing(Fig.3). 3. The ear of main stem was longer, more pods, heavier 1, 000 grains and more grain yield than ear of primary branches of all, Especially, as for that, the rate of yield constitution per plant in the direct-sowing was higher than in the transplanting(Fig. 4, 5, 6, 7, 8, 9). 4. The ear-length of the primary branches for each nodes had a tendency to the relatively slowly apical curve with the apex at the upper 3-4th node in the transplanting, but to the lower bias apical curve with the apex at the upper 2nd node in the dense-sowing. Especially, the possibility of growth at the lower ears was few in the early variety (Fig. 4). 5. The number of pod per ear on the primary branches for each nodes had a .tendency to the curve of ear-length with the apex at the upper 5-8thnode in the transplanting and at the upper 4-5th node in the dense-sowing (Fig. 5). Accordingly, a high positive correlation was found between the ear-length and number of pod per ear (Table 2) 6. In the transplanting, the high rate of effective ear was from the upper nods to the 12th node, but below the 16-17th nodes was ineffective. However, in the early dense-sowing the high rate of effective was to the 7th node. but below the 10th nodes was. ineffective. Especially, in the early variety has difficult to secure of poi-numbers for ineffective of the lower nodes(Fig. 6.). 7. The density of pod setting of the ear of main stem was the longest of all ears, and the lower nods were, the shorter it became. That had a tendency to the evidently apical growth. However. in the early variety, it was lengthened according to growth of ear-length(Fig.7). 8. The pod-length of the medium nodes was longer than the upper and lower, and the possitive correlation between pod-length and number of grain per poi was very high(Table 2.). 9. In the grain yield per node of primary branches, the most yielding node of transplanting was the upper 9th node, of dense-sowing 4-5th node(Fig 8.), and the possitive correlation between grain yield per node and ear-length or number of pod per ear was very high(Table 2). 10. The grain yield of ear of main stem was higher than that of primary branches in the percentage of dependence for grain yield per plant. The limint node of 50% of dependence to cumulative grain yield per plant was the upper 7-8th node in tranplanting, in the early dense-sowing 4-5th node, and in tke late dense-sowing-3th node(Fig. 9). 11. In the weight of 1, 000 grains the lower nodes were, the lighter it becames in dense-sowing. Therefore, this was also lighter than in the transplanting to the (Fig. 10.). 12. The oil content of grain at the medium nodes was low in the early variety, but at the ear of main stem and upper 1st node it was extremely high(Fig. 11.).

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