• Journal of Ecology and Environment
• /
• 제37권2호
• /
• pp.61-67
• /
• 2014

Mankyua chejuense is a native endangered plant distributed only in Gotzawal, a forested wetland, in Jeju Province, Korea. In order to determine the optimal environmental conditions for the growth and development of M. chejuense, we investigated the above- and below-ground growth responses and survival rate to various soil texture (sand and clay), water regimes (flooding and non-flooding), and $CO_2+T$ (ambient and elevated) conditions. All of the treatments had significant effects on aboveground growth parameters, while only the water regime and $CO_2+T$ treatments influenced belowground growth. The survival rate of M. chejuense was about twice higher under the sand, non-flooding and elevated $CO_2+T$ conditions than clay, flooding and ambient $CO_2+T$ conditions. These results indicate that M. chejuense grows in well-drained sandy soil conditions and elevated $CO_2$ concentration and temperature situations. Thus, there is a need to maintain M. chejuense under constant non-flooding soil conditions by implementing appropriate soil drainage strategies.

• 한국발생생물학회지:발생과생식
• /
• 제23권2호
• /
• pp.149-160
• /
• 2019

This study examined the effects of different photoperiod conditions on olive flounder (Paralichthys olivaceus), a commercially important species in Korea. Daily variations in the expression of mRNA for the growth-related genes arylalkylamine N-acetyltransferase2 (AANAT2), preprosomatostatin1 (PSS1), and growth hormone (GH) were examined under a 12 h light:12 h dark photoperiod. All the genes were expressed at higher level during the dark period. Melatonin injections increased the expression of GH, but did not significantly affect the expression of PSS. Under short-day conditions (10 h:14 h), the fish gained more weight than under long-day conditions (14 h:10 h). A long nighttime induced melatonin secretion and increased the expression of GH mRNA, promoting weight gain in this species. Therefore, we thought that the long day condition in raising olive flounder may be effective in inducing body growth.

• 보건교육건강증진학회지
• /
• 제12권1호
• /
• pp.111-127
• /
• 1995

This study was designed to investigate the relationships between children's physical growth and health and their raising conditions and to find out the important conditions to improve their physical growth and health. The rasing conditions were classified into three major parts; i. e., family conditions, conditions of nutrition up-taking, and conditions of rest or sleep and exercise or play. Then, the questionnaire including the items to survey these three areas of raising condition and the items to evaluate the health status were given to children' mothers or fathers and filled up by them. The data of their 4 anthropometric measures; body weight, stature, sitting height and chest girth, were also collected from their latest records of health examination. The data of health status were converted to health scores representing 6 domains of health; digestive organs, respiratory organs, auto-nerve systems, fatigue, others and health as a whole. Then, correlations of raising conditions were determined with four antropometric measures and 6 health scores as criterion variables. Then, number of families to live together, and child's birth order in the domain of family conditions, habits of unbalanced diet, eating frequency of eggs, fruits, green and yellow vegetables, light colored vegetables, milk products in the domain of nutrition up-take, and the time for study at home, the place for play, the number of friends to play with together, the hours for playing out of door, the hours for playing sports, and the hours to move their body for assisting house keeping were picked out to investigate their relationships with physical growth and health status. Then, their habits of unbalanced diet and eating frequency of eggs, green or yellow colored vegetables, and milk products were found more influential conditions and more over, birth order, the time for study at home, the time to play out of door showed moderate degree of connection with physical growth and health status in early childhood.

• Nuclear Engineering and Technology
• /
• 제33권5호
• /
• pp.526-538
• /
• 2001

Fatigue tests in air and in room temperature water were performed to obtain comparable data and stable crack measuring conditions. In air environment, fatigue crack growth rate was increased with increasing temperature due to an increase in crack tip oxidation rate. In room temperature water, the fatigue crack growth rate was faster than in air and crack path varied on loading conditions. In simulated light water reactor (LWR) conditions, there was little environmental effect on the fatigue crack growth rate (FCGR) at low dissolved oxygen or at high loading frequency conditions. While the FCGR was enhanced at high oxygen condition, and the enhancement of crack growth rate increased as loading frequency decreased to a critical value. In fractography, environmentally assisted cracks, such as semi-cleavage and secondary intergranular crack, were found near sulfide inclusions only at high dissolved oxygen and low loading frequency condition. The high crack growth rate was related to environmentally assisted crack. These results indicated that environmentally assisted crack could be formed by the Electrochemical effect in specific loading condition.

• 한국농림기상학회지
• /
• 제4권1호
• /
• pp.1-11
• /
• 2002

본 연구는 경기도 가평, 광주, 그리고 충청북도 영동에 식재된 잣나무 차대검정림을 대상으로 미기후가 잣나무 초기생장에 미치는 영향을 구명하기 위하여 수행하였다. 이를 위해 먼저 지역별ㆍ임령별로 평균 흉고직경, 평균 수고, ha당 흉고단면적, ha당 재적 등의 임분통계량을 측정ㆍ요약하였으며, 이에 근거하여 10년 생부터 20년 생까지 10년 간의 초기생장에 대한 임분변수별 연년생장량을 파악하였다. 환경요인으로서 각 차대검정림의 지역별 미기후 조건이 생장에 미치는 영향을 분석하기 위해 지형기후학적 방법과 공간통계 기법을 사용하였다. 이상과 같이 얻어진 연도별 기후 추정치에 근거하여 임목생장에 영향을 미치는 30개의 기후지수를 각 차대검정림별로 추정하였다. 최종적으로 이들 30개의 기후지수와 각 임분변수별 연년생장량 간의 상관분석 및 회귀분석을 통하여 국지기후가 잣나무 생장에 미치는 영향을 파악하였다. 지역별 잣나무의 초기생장은 경기도 가평과 광주의 순서로 우수하였으며, 충청북도 영동은 매우 저조한 것으로 나타났다. 이러한 지역별 생장특성은 각 연구 대상지의 미기후와 밀접한 관련을 가지고 있는데, 기온이 낮고 높은 습도를 유지하는 지역이 잣나무 생장에 적합한 것으로 분석되었다. 특히 상관분석과 임분 변수별 생장을 추정하기 위해 도출된 최적 회귀식에 채택된 기후지수를 보면 잣나무의 초기 생장에 결정적인 영향을 미치는 미기후 조건은 낮은 기온인 것으로 판명되었다.

• 한국환경농학회지
• /
• 제27권4호
• /
• pp.362-367
• /
• 2008

The legume-rhizobia symbiosis is an important source of plant growth and nitrogen fixation for many agricultural systems. This study was conducted to investigate the effects of salinity stress on nitrogen fixation and growth of pea (Pisum sativum L.), which has antimutagenic activities against chemical mutagen, inoculated with R. leguminosarum bv. viciae cultured with additional plant-to-rhizobia signal compounds, naringenin (NA,15 uM), methyl-jasmonate (MJ, 50 uM) or both, under greenhouse conditions. Three salinity levels (0.6, 3.0 and $6.0\;dS\;m^{-1}$) were imposed at 3 days after transplanting and maintained through daily irrigations. Addition of signal compounds under non-stress and stress conditions increased dry weight, nodule numbers, leaf area and leaf greenness. The inducers increased photosynthetic rate under non-stress and stress conditions, by approximately 5-20% when compared to that of the non-induced control treatment. Under stress conditions, proline content was less in plants treated with plant-to-bacteria signals than the control, but phenol content was significantly increased, compared to that of the control. The study suggested that pre-incubation of bacterial cells with plant-to-bacteria signals could enhance pea growth, photosynthesis, nitrogen fixation and biomass under salinity stress conditions.

• 동아시아식생활학회지
• /
• 제11권3호
• /
• pp.219-224
• /
• 2001

This study was conducted to investigate the optimal conditions for the growth of soybean sprouts by ozone water watering. Optimal conditions for ozone water watering of soybean sprouts during cultivation at 2$0^{\circ}C$ were evaluated with ozone concentration(0.1~O.5 ppm) and watering frequency(1~9 times) by response surface methodology. The optimal conditions for growth of soybean sprouts were ozone concentrations of 0.20~0.32 ppm, ozone treatment frequency of 3.0~4.4 times. Germination rates, hypocotyl weights and hypocotyl lengths in the soybean sprouts cultivated under the optimal conditions increased by 13.3, 10.1 and 11.9%, respectively, whereas root weights decreased by 89.0%.

• Journal of Microbiology and Biotechnology
• /
• 제1권2호
• /
• pp.121-125
• /
• 1991

The culture conditions and nutritional requirements for enhanced mycelial growth of the ectomycorrhizal fungus P. tinctorius SMF were determined in flask scale experiments. Optimum culture conditions for growth of P. tinctorius SMF in a further modified Melin-Norkrans broth were as follows; temperature 25~$27^{\circ}C$, agitation 120 rpm, and pH 4.0. P. tinctorius SMF utilized various carbon sources including monosaccharides, disaccharides, and polysaccharides. D-Glucose and mannitol were respectively the first and second most suitable carbon sources for mycelial growth. With D-Glucose as the principal carbon source, supplementation of modified Melin-Norkrans (MMN) broth with Lysine (800 mg/l), Glutamic Acid (500 mg/l), or Proline (50 mg/l) enhanced mycelial yields 63%, 34%, and 22% respectively as compared to growth in medium lacking amino acids. ThiaminㆍHCl＋biotin＋pyridoxine supplementation also enhanced growth. As compared to mycelial growth in the MMN medium, growth of P. tinctorius SMF was enhanced 120% in MMN broth when the carbon/nitrogen ratio was 25/1 in citrate buffer at pH 4.5, and growth was 50% greater in MMN broth of carbon/nitrogen ratio with a 10/1~20/1 without using the buffer. Standard conditions established for growth of P. tinctorius SMF in MMN broth were 25~$27^{\circ}C$, agitation 120 rpm, buffered to pH 4.0 with citrate, in MMN medium containing 10 g/l D-glucose supplemented with 800 mg/l lysine. In this medium the carbon/nitrogen ratio was 20/1~25/1, and the maximal mycelial yield ($Y_{x/s}$ ) was 0.472 (4.72 mg/ml) after 7 days of incubation, as compared to 0.214 (2.14 mg/ml), when the fungus was grown in standard MMN broth.

• 한국미생물·생명공학회지
• /
• 제22권5호
• /
• pp.522-530
• /
• 1994

Bacteriocin-producing lactic acid bacteria, Lactococcus sp. HY 449, was isolated from dairy products. Using response surface methodology, the various concentrations of medium compo- nents (tryptone, glucose, yeast extract, tween 80, and initial pH) were tested to find the optimum conditions for maximum bacteriocin production and growth of Lactococcus sp. HY 449. Central composite design was used to control the concentrations of medium components in the experiment. Bacteriocin production and cell growth of Lactococcus sp. HY 449 were most affected by glucose and yeast extract. Estimated optimum growth conditions of Lactococcus sp. HY 449 were as follows; tryptone 1.08%, glucose 1.129%, yeast extract 0.674%, tween 80 0.11%, and initial pH 7.19. Also estimated optimum conditions for bacteriocin production were tryptone 0.937%, glucose 1.108%, yeast extract 0.163%, tween 80 0.09%, and initial pH 6.98.

• 한국작물학회지
• /
• 제51권1호
• /
• pp.48-52
• /
• 2006

Naturally occurring soybean isoflavones are known to be influenced by various genetic and environmental conditions. Growth, yield, and isoflavone content were determined in four different cultivars of soybean grown under drained paddy and upland fields. Most of growth characteristics and yield components of four different soybean cultivars harvested in drained paddy field were greater than those in upland field, regardless of cultivar. By means of high performance liquid chromatography, total daidzein and genistein contents of soybean in drained paddy field were increased up to 40 and 35%, respectively, compared with those in drained paddy field. Besides isoflavone contents, the growth and yield of soybean were significantly affected by cultivar and field conditions, indicating the necessity of genetic program for soybean cultivars appropriate to drained paddy field conditions. In conclusion, converting paddy field into upland may effectively improve soybean cropping system, especially in terms of isoflavone increment under paddy field conditions.