• 한국자원식물학회지
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• 제18권1호
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• pp.117-122
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• 2005

본 연구는 산림의 유용한 식물중 하나인 멸가치의 생육특성을 밝혀 보고자 습도와 광도를 조사하였다. 주요 산채류중 하나인 멸가치의 생약성분이 정신분열증을 일으키는 dopamine함량 감소작용을 일으켰다는 보고 등 자원으로서의 가치가 큰 것으로 나타났다. 이러한 멸가치의 생육에 가장 큰 영향을 주는 것은 습도로 $50\%$ 이상이 좋은 것으로 나타났다. 또한 온도변화가 자고 광량은 $200\;{\mu}mol\;s^{-1}m^{-2}$이하의 곳이 생육에 적합한 장소로 분석되었다. 이 연구 결과 음지식물의 증식에 있어서 습도를 $50\%$이상 유지하는 것이 중요한 것으로 나타났다.

• Archives of Pharmacal Research
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• 제16권4호
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• pp.276-282
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• 1993

This study has been undertaken to examine the effect of 3-methylcholanthrene (3MC) on rat uterine growth and to understand the mechanism of action of 3MC in rat uterus. After diethylstilbesterol(DES) or tamoxifen(TAM) or 3MC or DES plus TAM or DES plus 3MC was administered into immature female rats, uterine weight over corn oil-treated uteri. 3MC treatment had no effect on uterine weight but, DES stimulated uterine weight was inhibited by 3MC concomitant tratment. While TAM alone treatment showed slight increase in uterine wieght, inhibited uterine growth simulated by DES when it was adiministrated with DES condirect binding assay with $[^3H]$ estradiol and the relative binding affinities of 3MC and TAM were estimated by competetion assy. Estradiol tumed out to have high affinity for rat uterine estrogen receptor (kd = 0.4 nM). The relative binding affinities of TAM and 3MC were 1% and 4.7% that of DES for rat uterine estrogen receptor, respectively. 3MC was shown to have similar affinity for eat uterine estrogen receptor to that of TAM. Effects of DES 3MC and TAM administration in vivo on rat uterine estrogen recptor level were examined. It was confirmed that the estrogen, DES and antiestrogen, TAM decreased estrogen receptor levels from rat ulterus and also 3MC decreased rat uterine estrogen receptor level when rats were treated with DES, TAM and 3MC in vivo. Data indicates that 3MC acts as an antiestrogen mediated through estrogen receptor system.

• Journal of Plant Biology
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• 제30권3호
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• pp.205-213
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• 1987

Soybean, inoculated with effective Rhizobium japonicum 110, were grown by sand culture with nutrient solution containing either of 0, 1, 3, 10 or 30mM NO3-/l, and analyzed growth characteristics, NR activity, N2-fixation activity, and changes of ureide contents during the growing period. The amount of nodule formation decreased abruptly by nitrate treatment, the maximum nodule dry weight was 1.59, 1.05, 0.78, 0.09 and 0.008 g plant-1, respectively for each treatment on the 98th day. Specfic activity of N2-fixation showed the maximum rates of 140, 101, 37, 5 and 2.2 nM dw.mg-1.hr-1, respectively for each treatment in the earlier growth period. The maximum acetylene reduction activity on the 98th day after sowing was 81.5, 35.3, 14.3, 0.1 and 0.0045 $\mu$M C2H4 plant-1.hr-1, respectively for 0, 1, 3, 10 and 30 mM of NO3- gradients. Nitrate reduction activity increased along with nitrate gradients, and decreased abruptly with age. Relative abundance of ureides in plant organs was high in reproductive growth, and showed the maximum value in fully symbiotic dependent plant. Relative abundance of ureides in stem is a useful indication for the evaluation of nitrogen fixation in nodules of symbiotic plant.

• Mycobiology
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• 제36권2호
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• pp.81-87
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• 2008

The optimal conditions for mycelial growth of Phellinus linteus ATCC 26710 were determined to be a log length of 20 cm, temperature of $30^{\circ}C$ and pH of 6.0. Mycelial growth was excellent on the mushroom complete medium, and was optimal when sucrose, man nose and glucose were supplied as carbon sources. Potassium nitrate and sodium nitrate as nitrogen sources supported good mycelial growth. To evaluate P. linteus mycelial colonization on logs, sterilized short log inoculation, drilling inoculation and log-end sandwich inoculation techniques were used. Only sterilized short log inoculation produced good mycelial colonization. Initial mycelial growth and full mycelial colonization were best on 20 cm logs having 42% moisture content. The initial mycelial growth of P. linteus was accelerated over 12hr of sterilization. Basidiocarp formation was optimal using a burying method of logs after $5{\sim}6$ months, and fruiting body formation was superior in cultivation house conditions of $31{\sim}35^{\circ}C$ and in excess of 96% relative humidity.

• 산경연구논집
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• 제6권1호
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• pp.5-15
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• 2015

Purpose - This study reviews Cameroon's economic growth, crisis, and recovery, aiming to: review the principal factors of Cameroon's real economic growth; explore the causes of its economic crisis analyze the determinants of its economic recovery; and suggest appropriate policies to ameliorate economic growth. Research design, data, and methodology - By reviewing the relevant literature and economic indicators, we observed that from the 1980s to the present, Cameroon experienced all the possible business cycle phases: economic prosperity (until 1985), economic and social crisis (1986-1994), and renewed economic growth (after 1995). Results - As a result of the economic changes in Cameroon, its macroeconomic indicators have evolved. Poverty and inequality have changed in both quantitative and qualitative terms. Throughout the examined period, rural poverty has become more widespread, deeper, and more severe than urban poverty, while inequality has experienced greater increases in urban areas relative to rural zones. Conclusions -To reap maximum benefits and reduce poverty from these economic changes, Cameroon needs to liberalize trade and foreign exchange transactions to attract foreign investment, especially during the current globalization.

• Fisheries and Aquatic Sciences
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• 제15권1호
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• pp.57-62
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• 2012

Interspecific relationship between a euryhaline rotifer Brachionus rotundiformis and a cyclopoid copepod Apocyclops borneoensis was investigated in the laboratory culture. In a mixed culture of B. rotundiformis and A. borneoensis, population growth of B. rotundiformis was suppressed from day 10, while growth in a monoculture population continuously increased throughout the experimental period. However, the population growth of A. borneoensis in the mixed culture did not markedly differ from that in a monoculture population. Suppression of B. rotundiformis growth coincided with a decrease in the numbers of both non-egg-bearing and egg-bearing females, and increasing resting egg formation. Growth of A. borneoensis was not affected by the presence of the rotifer. However, relative growth index of ovisac bearing females in the mixed culture was 1.62 times higher than that in the monoculture. Presence of the copepod did not greatly reduce the food available to the rotifer population. The rotifer B. rotundiformis responded in a unique way, to stresses such as physical damage (filtering by A. borneoensis) with the production of many resting eggs to increase its chances of survival.

• 한국안전학회지
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• 제15권3호
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• pp.1-6
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• 2000

In fatigue crack growth test, it is important not only to analyze characteristics of fatigue crack growth but also to determine the threshold stress intensity factor, ${\Delta}K_{th}$. which is the threshold value of fatigue crack growth. Linear regression analysis using fatigue test data near the threshold is suggested to determine the ${\Delta}K_{th}$ in the standard test method but the ${\Delta}K_{th}$ can be affected by a fitting method. And there are some limitations on the linear regression analysis in the case of small number of test data near the threshold. The objective of this study is to investigate differences of the ${\Delta}K_{th}$ due to regression analysis method and to evaluate the relative error range of the ${\Delta}K_{th}$ in same fatigue crack growth test data.

• 미생물학회지
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• 제29권4호
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• pp.263-266
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• 1991

The growth of T. novellus in auto trophic and geterotrophic media was studied to determine the time required for cells to enter stationary phase and relative percentage of ribosomal proteins. When T. novellus was grown autotrophically, growth proceeded at a slow rate characteristic of autotrophs and did not enter log phase until the end of the first day. Logarithmic growth proceeded for 3-4 days at which time the cells entered the stationary phase. In particular, logarithmic growth was accompanied by decreasing pH of culture media and in the stationary phase the pH levelled off at 6.0, a decrease of 1.6 pH value compared to original pH of media. The pH decrease was greatest during log phase when cells oxidized thiosulfate to $H_{2}$$SO_{4}$. The doubling time was about 26h. In heterotrophic media growth proceeded at a much faster rate and cells entered stationary phase 20-22h after inoculation. The doubling time was 3h. The protein content of the ribosomes in T. novellus grown heterotrophically was 4.2% greater than those from the organism grown autotrophically.

• 한국가시화정보학회지
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• 제20권2호
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• pp.63-69
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• 2022

In this study, we numerically simulate the condensational growth of micron-sized particles traveling through a pipe filled with humidified air. Using the finite volume method and Lagrangian particle tracking technique, the mixture of particle-laden flow with moist air in a T-juction pipe is simulated. The condensational growth of particles is calculated by considering the mass transfer of vapor in the air onto the particle surface. The results indicate that the growth rate of the particles increases as the relative humidity of air is higher. Furthermore, the placement of a porous media with low permeability in the pipe could enhance the degree of condensational growth.

• 원예과학기술지
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• 제32권6호
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• pp.803-811
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• 2014

본 연구는 스탠다드 국화 '백마'의 흰녹병 발생과 생육에 미치는 시설 내의 상대습도(70, 80, 90, 95%)의 영향을 조사한 후, 온도(15, 20, $25^{\circ}C$)와 상대습도(60, 70, 80, 90%)의 상호관계를 알아보고자 실시되었다. 또한 흰녹병의 발생 초기부터 동포자퇴에서 소생자가 형성될 때까지 병 발생 단계를 관찰하였다. 국화 '백마'를 시설 재배 시 상대습도를 90% 이상 조건에서 40일간 처리되었을 때, 흰녹병 발생률이 97%, 주당 발병엽수가 10개, 발병엽당 병징수가 55개 이상으로 나타났다. 그러나, 상대습도를 70% 이하로 유지하면 흰녹병 발생률을 30% 낮출 수 있고, 한 주당 1-2개의 감염된 잎에 2개의 병징만 나타나 병해를 크게 줄일 수 있었다. 생체중과 엽수와 같은 절화의 품질은 다른 처리보다 상대습도 70% 처리에서 가장 우수하였다. 상대습도 90% 처리구에서 흰녹병에 감염된 국화를 정식한 후 6일 후에 첫 병징인 흰색 반점이 나타났고 (1단계), 1일 경과 후에 동포자가 잎의 표피 조직을 뚫고 나왔으며(2단계), 1-2일 후에 동포자의 수가 증가하면서 동포자퇴가 크게 형성되었다(3단계). 동포자에서 1-2일 후에 전균사체가 발달하였고(4단계), 4-5일 경과된 후 전균사체에서 소생자가 형성되었다(5단계). 시설 내 온도를 $25^{\circ}C$로 처리했을 때, 상대습도에 관계없이 흰녹병이 전혀 발생하지 않았다. 시설 내 온도가 $20^{\circ}C$에서는 상대습도에 관계없이 소생자수가 많았으나, 60%와 70%에서는 흰녹병이 발생하지 않았다. 시설 내 온도가 $15^{\circ}C$에서는 상대습도가 높을수록 소생자수가 많았고, 흰녹병 발생률도 높아졌으나, 상대습도가 낮은 60-70% 처리에서는 흰녹병 발생률이 14% 이하로 낮았다.