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Analysis on the Correlation Between Vegetation Structure and Environment Factors of the Geumosanseong-inside in Geumosan Provincial Park, in Korea (금오산도립공원의 금오산성 식생구조와 환경요인의 상관관계 분석)

  • Kim, Hyoun-Sook;Park, Gwan-Soo;Lee, Sang-Myong;Lee, Joong-Ku
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.23 no.2
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    • pp.49-67
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    • 2020
  • This study was conducted to compare and analyze forest vegetation distributed in Geumosanseong-inside in Geumosan Provincial Park from 2017.10 to 2019.6. The vegetation structure was classified by the phytosociological method and TWINSPAN and the correlation between the community structure and the environmental factors was analyzed using DCCA ordination analydsis. The vegetation structures are Quercus mongolica, Fraxinus mandshurica, Q. acutissima, Larix leptolepis, Prunus padus and Morus alba community by the phytosociological method and 16 communities under TWINSPAN. The importance value of Q. mongolica(64.5) was the highest, and followed by F. mandshurica, L. leptolepis, Acer pseudosieboldianum, M. alba, P. padus, Q. acutissima, Sorbus alnifolia, P. serrulata var. pubescens, F. sieboldiana, Rhododendron schlippenbachii and Castanea crenata which is consistent with species having the dominance status by analysis of the vegetation structure. As the results of DBH analysis for taxon with high importance values, Q. mongolica and M. alba represented normal distribution, and thus, the dominance status of these species is likely to continue. L. leptolepis will maintain the dominance status due to high density of large individuals as compared with species above medium size. However, it will decrease because of high mortality after increase in age class. F. mandshurica and P. padus continue to show dominance status due to high density of young individuals as compared with species above medium size. Q. acutissima have high density of individuals above intermediate size and low density of young individuals, and thus, will maintain the dominance status. A. pseudosieboldianum, F. sieboldiana and R.schlippenbachii which are arborescent will present continuously high dominance status because of high density of young individuals. Soil analysis shows that whereas pH, Ca2+ and Mg2+ in the research area were lower than the average values of overall forest soil and O.M, T-N, C.E.C and P2O5 were higher. We expected that these results were due to agricultures until 50 years ago in Geumosanseong-inside. As a result of DCCA ordination analysis using eleven environmental factors and communities classified by the phytosociological method analysis showed that Q. mongolica was distributed in the environment with higher elevation and O.M and steep slope, and lower P2O5, Mg2+ and Ca2+. In contrast to F. mandshurica, Q. acutissima was distributed in higher K+ and lower pH. L. leptolepsis was distributed in various environment.

Comparison of Herbicidal Action between Pyrazosulfuron - ethyl and Imazaquin (Pyrazosulfuron - ethyl과 Imazaquin의 살초작용 비교)

  • Hwang, I.T.;Choi, J.S.;Kim, J.S.;Cho, K.Y
    • Korean Journal of Weed Science
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    • v.16 no.4
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    • pp.317-326
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    • 1996
  • To know whether pyrazosulfuron-ethyl(PYR) and imazaquin(IMA), known as a acetolactate synthase(ALS) inhibitors, have a same herbicidal action pattern in rice(Oryza sativa) or barnyardgrass (Echinochloa crus-galli), an inhibition pattern and a response characteristics in combination with dymron or butachlor were investigated. In contrast to the phytotoxicity of rice treated with IMA, the one treated with PYR was completely tended to be recovered after 25 days after treatment. Safening effect of dymron against PYR was effectively developed to transplanted-rice, while such an effect was not shown in combination with IMA. In combination with PYR and butachlor, antagonistic effect was observed in both simultaneous or sequential treatment on bamyardgrass, however, additive effect was rather shown in combination with IMA and its activity was dominantly dependent on the first applied compound. $I_{50}$ of PYR and IMA on the ALS extracted from barnyardgrass was $4{\times}10^{-7}$M and $2.8{\times}10^{-6})$M, respectively. Butachlor did not affect their activities on ALS in vitro. These results suggest that PYR and IMA might have a different action each other in the pathway to a final herbicidal activity even though their primary action site is ALS.

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The Effects of Rotational Correlation Time of Paramagnetic Contrast Agents on Relaxation Enhancement: Partial Binding to Macromolecules (거대분자에 부분적으로 결합한 상자성 자기공명 조영제의 회전속도가 이완증강에 미치는 영향)

  • 장용민
    • Investigative Magnetic Resonance Imaging
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    • v.3 no.2
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    • pp.159-166
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    • 1999
  • Purpose : To evaluate the effect of rotational correlation time (${\tau}_R$) and the possible related changes of other parameters, ${\tau}_M,{\;}{\tau}_S,{\;}and{\;}(\tau}_V$ of gadolinium (Gd) chelate on T1 relaxation enhancement in two pool model. Materials and Methods : The NMRD (Nuclear Magnetic Relaxation Dispersion) profiles were simulated from 0.02 MHz to 800 MHz proton Larmor frequency for different values of rotational correlation times based on Solomon-Bloembergen equation for inner-sphere relaxation enhancement. To include both unbound pool (pool A) and bound pool (pool B), the relaxivity was divided by contribution from unbound pool and bound pool. The rotational correlation time for pool A was fixed at the value of 0.1 ns, which is a typical value for low molecular weight complexes such as Gd-DTPA in solution and ${\tau}_R$ for pool B was changed from 0.1 ns to 20 ns to allow the slower rotation by binding to macromolecule. The fractional factor of was also adjusted from 0 to 1.0 to simulate different binding ratios to macromolecule. Since the binding of Gd-chelate to macromolecule cab alter the electronic environment of Gd ion and also the degree of bulk water access to hydration site of Gd-chelate, the effects of these parameters were also included. Results : The result shows that low field profiles, ranged from 0.02 to 40 MHz, and dominated by contribution from bound pool, which is bound to macromolecule regardless of binding ratios. In addition, as more Gd-chelate bound to macromolecule, sharp increase of relaxivity at higher field occurs. The NMRD profiles for different values of ${\tau}_S$ show the enormous increase of low field profile whereas relaxivity at high field is not affected by ${\tau}_S$. On the other hand, the change in ${\tau}$V does not affect low field profile but strongly in fluences on both inflection fie이 and the maximum relaxivity value. The results shows a fluences on both inflection field and the maximum relaxivity value. The results shows a parabolic dependence of relaxivity on ${\tau}_M$. Conclusion : Binding of Gd-chelate to a macromolecule causes slower rotational tumbling of Gd-chelate and would result in relaxation enhancement, especially in clinical imaging field. However, binding to macromolecule can change water enchange rate (${\tau}_M$) and electronic relaxation ($T_le$) vis structural deformation of electron environment and the access of bulk water to hydration site of metal-chelate. The clinical utilities of Gd-chelate bound to macromolecule are the less dose requirement, the tissue specificity, and the better perfusion and intravascular agents.

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Analysis on the Leisure Constraint and Index Concentrate Here Improvement's Leisure Activities among the Private Security Agents Applying PPA Technique (PPA기법을 적용한 민간경호경비원의 여가제약과 중점개선 여가활동 참가지수 분석)

  • Kim, Kyong-Sik;Kim, Chan-Sun;Park, Young-Man
    • The Journal of the Korea Contents Association
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    • v.10 no.7
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    • pp.317-325
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    • 2010
  • This study aims to deduct the extensive improvement types of leisure activities of private security agents using PPA technique and to examine the influence of leisure constraint on the index of participation. Through this process, this study consequently will draw the priority list of investment on the policy for improving the welfare status of private security agents. In this study, judgement sampling was applied to 6 security agencies located in Seoul, 2010, and 267 cases were used in the final analysis. Collected data went through factor analysis, reliability analysis, paired t test, PPA analysis, and regression analysis by using SPSSWIN 17.0. The conclusions were drawn as follows. In regard to the reliability, Cronbach's $\alpha$ was over .768. First, there was a difference between the preference rate and the participation rate which are the participation index of the private security agents' leisure activities. concentrate here in leisure types turned out to be fitness activities, walking/jogging, tourism, a day-long travel, and keep up the cood work in leisure types are movies, domestic tourist attractions, dating, eating out, personal relationship, watching sports, reading, karaoke, TV video watching, drinking etc. low priority in leisure types are water sports, hiking, biking, soccer, photography, ball games, sky sports, playing go/janggi, inline skates, and cooking. Second, the leisure constraint affects the participation index of leisure activities. As the personal constraint, and surrounding conscious constraint which are the subordinate factors of the leisure constraint get bigger, the participation index of favored leisure activities become lower. In contrast, when the difficulties such as structural constraint, time and economical constraint are overcome, participation index of leisure activities go on the rise.

Evaluations and Comparisons of Body Surface Doses during Breast Cancer Treatment by Tomotherapy and LINAC Radiotherapy Devices

  • Lee, Hyun-Jik;Bae, Sun-Hyun;Cho, Kwang Hwan;Jeong, Jae-Hong;Kwon, Su-Il;Lee, Kil-Dong
    • Progress in Medical Physics
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    • v.28 no.4
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    • pp.218-225
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    • 2017
  • Effects on skin caused by the dose from linear accelerator (LINAC) opposing portal irradiation and TomoDirect 3-D modeling treatment according to the radiation devices and treatment methods were measured, and a comparative analysis was performed. Two groups of 10 patients each were created and measurements were carried out using an optically stimulated luminescence dosimeter. These patients were already receiving radiation treatment in the hospital. Using the SPSS statistical program, the minimum and maximum average standard deviations of the measured skin dose data were obtained. Two types of treatment method were selected as independent variables; the measured points and total average were the dependent variables. An independent sample T-test was used, and it was checked whether there was a significance probability between the two groups. The average of the measured results for the LINAC opposing portal radiation was 117.7 cGy and PDD 65.39% for the inner breast, 144.7 cGy and PDD 80.39% for the outer breast, 143.2 cGy and PDD 79.56% for the upper breast, 151.4 cGy and PDD 84.11% for the lower breast, 149.6 cGy and PDD 83.11% for the axilla, and 141.32 cGy and PDD 78.51% for the total average. In contrast, for TomoDirect 3-D conformal radiotherapy, the corresponding measurement values were 137.6 cGy and PDD 76.44%, 152.3 cGy and PDD 84.61%, 148.6 cGy and PDD 82.56%, 159.7 cGy and PDD 88.72%, and 148.6 cGy PDD 82.56%, respectively, and the total average was 149.36 cGy and PDD 82.98%. To determine if the difference between the total averages was statistically significant, the independent sample T-test of the SPSS statistical program was used, which indicated that the P-value was P=0.024, which was 0.05 lower than the significance level. Thus, it can be understood that the null hypothesis can be dismissed, and that there was a difference in the averages. In conclusion, even though the treatment dose was similar, there could be a difference in the dose entering the body surface from the radiation treatment plan; however, depending on the properties of the treatment devices, there is a difference in the dose affecting the body surface. Thus, the absorbed dose entering the body surface can be high. During breast cancer radiotherapy, radiation dermatitis occurs in almost all patients. Most patients have a difficult time while undergoing treatment, and therefore, when choosing a radiotherapy treatment method, minimizing radiation dermatitis is an important consideration.

Various Nitrogen Efficiencies and their Interrelation Among Rice Varieties (수도품종간(水稻品種間) 여러 질소효율(窒素効率)의 상호관계(相互關係))

  • Park, Hoon;Mok, Sung Kyun
    • Korean Journal of Soil Science and Fertilizer
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    • v.9 no.2
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    • pp.83-92
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    • 1976
  • The relationships between various nitrogen efficiencies among 57 rice cultivars grouped into three developmental categories were investigated by simple correlation with (12kg/10a) and without nitrogen fertilizer under the field condition. The relationship showed similar in a group or among all varieties of three groups. Yield among varieties showed highly significant correlation with Fe (fertilization efficiency: yield increment/nitrogen applied), E (nitrogen efficiency for yield), Ef(efficiency of nitrogen derived from fertilizer) and Eu (fertilizer use efficiency: nitrogen derived from fertilizer divided by total nitrogen applied). The E was correlated significantly and positively with harvest index (HI), percent translocation (T) of nitrogen to ear and negatively with nitrogen uptake amount (N), nitrogen concentration in grain (GN%) and in straw (SN%). The E depends almost on Ef and only inTongil group partly on Es (efficiency of nitrogen derived from soil). The Ef contributes to Fe more than Eu does (Fe = $Ef{\cdot}Eu$). It appears that Ef and Eu increased from the old group to the recommended local varieties, but only EF and Es increased markedly when rice was developed from recommended local group to Tongil line ($indica{\times}japonica$ hybrid selction). The fact that E and Fe depend more on Ef among rice varieties is very good contrast to the result that E and Fe depend more on Es and Eu respectively among soils in the previous investigatigation. The Ef appears as the most important parameter for rice varietal selection under fertilizer application system.

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Cultivation and Electron Microscopy of Bovine Leukemia Virus from Peripheral Blood Lymphocytes of Holstein-Friesian Dairy Cattle (젖소 말초혈액 림프구로부터 소백혈병 바이러스 배양 및 전자현미경적 관찰)

  • Yoon, Soon-Seek;Park, Jung-Won;Byun, Jae-Won;Kang, Mun-Il;Yoo, Han-Sang;Han, Hong-Ryul
    • Applied Microscopy
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    • v.35 no.1
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    • pp.23-30
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    • 2005
  • Many studies have been performed on the bovine leukemia virus (BLV) since bovine leukosis had been reported in 1968 in Korea. However, there was no report on the ultrastructural examination of BLV. An attempt to detect C-type viral particles in the cultured peripheral blood lymphocytes of Holstein-Friesian dairy cattle, was made to determine whether in vitro viral expression might be used as a reliable method to identify the cow which is likely to transmit BLV. In transmission electron microscopic (TEM) examination, the virus particles were found predominantly outside of the lymphocytes even though a few particles were also observed within the membrane bound cytoplasmic vacuoles. All of them were C-type particles consisting of a central, electron-dense core separated by a clear area from a limiting envelope with a unit membrane structure. Virus particles were easily detected in the lymphocyte which was cultured with medium supplemented with either T-lymphocyte mitogen (conconavalin A) or B-lymphocyte mitogen (lipopolysaccharide). Identical viral particles, although fewer, were also consistently present in the lymphocytes cultured with medium which was containing foetal bovine serum (FBS) only and which was containing neither FBS or mitogen. By contrast, no virus particle was detected in extensive examination of lymphocytes before culture. In conclusion, the BLV cultivation and detection methods established in this study could be used as a tool to identify and eliminate the cattle which can transmit the BLV.

Investigation and Analysis of Allergy-related SNPs for Allergy Affected Students in a high school. (과학영재학교 학생들이 알러지 관련 SNP 탐색고 분석)

  • 김경원;이호경;김현근;김수영;안정훈
    • Journal of Life Science
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    • v.14 no.5
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    • pp.847-854
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    • 2004
  • Allergy is a multi-factorial disease influenced by genetic and environmental factors. As the number of allergy-affected people is increasing in developed countries, there is an increasing interest in genetic predisposition to the allergy. A number of genes and chromosomal region have been identified to be linked to allergy including rhinitis, asthma and atopy. In order to understand the genetic background for the allergy-affected people, we investigated genetic predisposition among students enrolled in Busan Science Academy. Among 138 students, about 30% students had some allergy-related disorder including rhinitis, asthma and atopy. We analyzed several single nucleotide polymorphisms (SNPs) within two genes, Inter-leukin-4(IL-4) and Interleukin-4 receptor(IL-4R), which are involved in the induction of allergy reaction with the Th2 immunity. For 96 samples obtained from students, we analyzed 9 SNPs including -590 C/T and -34 C/T in IL-4, and I75V, Q576R, E375A, e406R, 5411L, S761P and S727A in IL-4R. From the analysis, these SNPs showed slight differences among normal and allergy-affected students, but these differences was not enough to predict the predisposition to the allergy. In contrast to previous reports, we could not find SNP(s) related with allergy. These results suggest that genetic tests recently performed in Korea widely have to be reassessed for its validity of genetic predisposition. [Supported by grants from MOST]

Modelling Pasture-based Automatic Milking System Herds: System Fitness of Grazeable Home-grown Forages, Land Areas and Walking Distances

  • Islam, M.R.;Garcia, S.C.;Clark, C.E.F.;Kerrisk, K.L.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.6
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    • pp.903-910
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    • 2015
  • To maintain a predominantly pasture-based system, the large herd milked by automatic milking rotary would be required to walk significant distances. Walking distances of greater than 1-km are associated with an increased incidence of undesirably long milking intervals and reduced milk yield. Complementary forages can be incorporated into pasture-based systems to lift total home grown feed in a given area, thus potentially 'concentrating' feed closer to the dairy. The aim of this modelling study was to investigate the total land area required and associated walking distance for large automatic milking system (AMS) herds when incorporating complementary forage rotations (CFR) into the system. Thirty-six scenarios consisting of 3 AMS herds (400, 600, 800 cows), 2 levels of pasture utilisation (current AMS utilisation of 15.0 t dry matter [DM]/ha, termed as moderate; optimum pasture utilisation of 19.7 t DM/ha, termed as high) and 6 rates of replacement of each of these pastures by grazeable CFR (0%, 10%, 20%, 30%, 40%, 50%) were investigated. Results showed that AMS cows were required to walk greater than 1-km when the farm area was greater than 86 ha. Insufficient pasture could be produced within a 1 km distance (i.e. 86 ha land) with home-grown feed (HGF) providing 43%, 29%, and 22% of the metabolisable energy (ME) required by 400, 600, and 800 cows, respectively from pastures. Introduction of pasture (moderate): CFR in AMS at a ratio of 80:20 can feed a 400 cow AMS herd, and can supply 42% and 31% of the ME requirements for 600 and 800 cows, respectively with pasture (moderate): CFR at 50:50 levels. In contrast to moderate pasture, 400 cows can be managed on high pasture utilisation (provided 57% of the total ME requirements). However, similar to the scenarios conducted with moderate pasture, there was insufficient feed produced within 1-km distance of the dairy for 600 or 800 cows. An 800 cow herd required 140 and 130 ha on moderate and high pasture-based AMS system, respectively with the introduction of pasture: CFR at a ratio of 50:50. Given the impact of increasing land area past 86 ha on walking distance, cow numbers could be increased by purchasing feed from off the milking platform and/or using the land outside 1-km distance for conserved feed. However, this warrants further investigations into risk analyses of different management options including development of an innovative system to manage large herds in an AMS farming system.

Distribution of Nutrients and Phytoplankton Biomass in the Area Around the South Shetland Islands, Antarctica (남극 남쉐틀랜드군도 주변 해역의 영양염과 식물플랑크톤 생물량 분포)

  • Kim, Dong-Seon;Kang, Sung-Ho;Kim, Dong-Yup;Lee, Youn-Ho;Kang, Young-Chul
    • Ocean and Polar Research
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    • v.23 no.2
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    • pp.77-95
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    • 2001
  • Temperature, salinity, nutrients, chlorophyll-a, and primary production were measured within the upper 200 m water column in the area around the South Shetland Islands in January, 2000. Surface temperature was relatively high in the Drake Passage north of the South Shetland Islands and low in the northeastern area of the Antarctic Peninsula. In contrast, surface salinity was low in the Drake Passage and increased toward the Antarctic Peninsula, reaching the maximum value in the northeastern area of the Antarctic Peninsula. Surface nutrients were low in the Drake Passage and high in the area near the South Shetland Islands. Surface chlorophyll-a was also low in the Drake Passage and near the Antarctic Peninsula and high in the area of the northern King George Island. The study area could be classified as four geographical zones based on the characteristic shape of the T/S diagrams;the Drake Passage, the Bransfield Strait, the mixed zone, and the Weddell Sea. Each geographical zone showed apparently different physical, chemical, and biological characteristics. Phytoplankton biomass was relatively low in the Drake Passage and the Weddell Sea and high in the Bransfield Strait and the mixed zone. The low phytoplankton biomass in the Weddell Sea could be explained by the low water temperature and deep surface mixing down to 200 m. The high grazing pressure and low availability of iron could be responsible for the low phytoplankton biomass in the Drake Passage.

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