• 한국잡초학회지
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• 제30권2호
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• pp.103-110
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• 2010

일년생 잡초인 물달개비 및 올챙이고랭이의 출아와 초기생장을 예측하기 위한 모델 구축을 위하여 온도조건을 달리한 식물생장상에서 포트실험을 수행하였다. 이들 잡초의 출아 및 초기생장과 유효적산온도와의 관계를 비선형회귀로 분석한 결과 온도조건에 상관없이 각각 Gompertz 모델 및 logistic 모델로 설명이 잘 되었다. 물달개비 및 올챙이고랭이의 최대 출아율의 50%에 필요한 유효적산온도는 각각 69.3 및 $94.8^{\circ}C$이었으며, 4엽기에 이르는데 필요한 유효 적산온도는 각각 247 및 $234^{\circ}C$이었다. 본 연구에서 개발된 모델로 분석한 결과 평균 기온이 $3^{\circ}C$ 상승하게 되면 이들 잡초의 50% 출아는 물달개비의 경우 1일, 올챙이고랭이의 경우는 2일 빨라지고, 4엽기에 다 다르는 날짜는 이들 잡초 모두 3일이 빨라질 것으로 예측되었다. 따라서 온도상승조건에서 물달개비 및 올챙이고랭이를 효과적으로 방제하기 위해서는 현재의 처리시기보다 약 2-3일 빨라져야 할 것으로 예상된다.

• 아시안잔디학회지
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• 제15권2호
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• pp.65-76
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• 2001

잔디(Zoysia japonica)의 1차 생산성과 광조건과의 상호작용을 평가하고 생리생태학적인 특성을 규명하기 위하여 일조시간을 조절한 상태에서 인공군락의 물질생산과 성장해석에 미치는 영향에 대하여 분석하였다. 그 결과의 요약은 다음과 같이 하였다. 1. RGR은 각 시험구공히 이식 후 20일경까지의 생장과정에서 높게 나타났고 이후 생장이 진행됨에 따라 낮아지는 경향을 보였다. 최고치는 Control에서 이식 후 20일과 20일사이의 생장과정에서 2.13g/g.10-days로 나타났으며 광조사 시간이 짧을수록 이식 후 초기생장부터 현저히 낮은 치를 보였으며 짧은 시간 자연광 조사가 RGR을 현저히 저하시키는 결과를 보였다. 2. NAR은 3시간 광조사구를 제외한 각구 공히이식 후 초기 생장과정에서 높은 치를 보였고, 이후 생장이 진행됨에 따라 낮은 치를 나타내었으며 최고치는 Control구에서 35g/$m^2$ 10days로 나타났다. 광조사 시간이 짧은수록 현저히 낮은 치를 보였으며 특히 3시간 광조사구에서는 초기생장부터 현저히 낮은 치를 나타내었고 변화도 감소하였다. LAI와는 역상관, RGR과는 정의 상관관계를 나타내었다. 3. LAR은 Control구와 각 일조시간 조절구에서는 광조사 시간이 짧을수록 이식초기부터 현저히 높은 LAR치를 보였고, 특히 3시간 광조사구에서는 현저히 높은 치를 보였으나 생장과정에 따른 증가율은 낮게 나타났다. LAR은 RGR과 NAR에 대하여 역의 상관관계를 나타내었다. 4. CGR은 각구 공히 이식 후 50일까지는 생장이 진행됨에 따라 증가하였고 이후의 생장과정에서는 낮아지는 경향을 보였으며 최고치는 1.56g/$ extrm{cm}^2$10days로 Control구에서 이식 후 60일경에 나타났다. LAI와는 정의 상관을 나타내었고 최적엽면적지수 Control구와 9시간, 7시간, 5시간 및 3시간, 일조시간 조절구에서는 각각 1.87, 1.12, 0.83, 0.18로 나타났다.

• Advances in concrete construction
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• 제16권5호
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• pp.255-267
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• 2023

The production of ultra-early-strength concrete (UESC) traditionally involves complexity or necessitates high-temperature curing conditions. However, this study aimed to achieve ultra-early-strength performance solely through room-temperature curing. Experimental results demonstrate that under room-temperature (28℃) curing conditions, the concrete attained compressive strengths of 20 MPa at 4 hours and 69.6 MPa at 24 hours. Additionally, it exhibited a flexural strength of 7.5 MPa after 24 hours. In contrast, conventional concrete typically reaches around 20.6 MPa (3,000 psi) after approximately 28 days, highlighting the rapid strength development of the UESC. This swift attainment of compressive strength represents a significant advancement for engineering purposes. Small amounts of steel fibers (0.5% and 1% by volume, respectively) were added to address potential concrete cracking due to early hydration heat and enhance mechanical properties. This allowed observation of the effects of different volume contents on ultra-early-strength fiber-reinforced concrete (UESFRC). Furthermore, the compressive strength of 0.5% and 1% UESFRC increased by 16.3% and 31.3%, respectively, while the flexural strength increased by 37.1% and 47.9%. Moreover, toughness increased by 58.2 and 69.7 times, respectively. These findings offer an effective solution for future emergency applications in public works.

• Clinical and Experimental Pediatrics
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• 제54권2호
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• pp.55-63
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• 2011

Prader-Willi syndrome (PWS) is a complex multisystem genetic disorder that is caused by the lack of expression of paternally inherited imprinted genes on chromosome 15q11-q13. This syndrome has a characteristic phenotype including severe neonatal hypotonia, early-onset hyperphagia, development of morbid obesity, short stature, hypogonadism, learning disabilities, behavioral problems, and psychiatric problems. PWS is an example of a genetic condition caused by genomic imprinting. It can occur via 3 main mechanisms that lead to the absence of expression of paternally inherited genes in the 15q11.2-q13 region: paternal microdeletion, maternal uniparental disomy, and an imprinting defect. Over 99% of PWS cases can be diagnosed using DNA methylation analysis. Early diagnosis of PWS is important for effective long-term management. Growth hormone (GH) treatment improves the growth, physical phenotype, and body composition of patients with PWS. In recent years, GH treatment in infants has been shown to have beneficial effects on the growth and neurological development of patients diagnosed during infancy. There is a clear need for an integrated multidisciplinary approach to facilitate early diagnosis and optimize management to improve quality of life, prevent complications, and prolong life expectancy in patients with PWS.

• Journal of Ginseng Research
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• 제11권1호
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• pp.77-83
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• 1987

인삼사포닌이 벼(Oryza sativa L.)의 초기생장 및 발아에 미치는 영향을 조사하기 위하여, 볍씨를 $10^{-4}$% 사포닌용액에 침종시킨 후, ${\circ}C$에서 성장시켰다. 인삼사포닌용액($10^{-4}$%)에 60시간 동안 침종한 볍씨(시험군)는 증류수에 침종한 대조군에 비해 시간에 따른 생장이 촉진(약 10%)되었으며, 잎의 출현시기도 통계적으로 빨랐다. 또한, 볍씨 발아시의 주요효소인 amylase의 활성을 12, 24, 48, 72시간 침종한 볍씨파쇄액에서 조사한 결과, 시험군이 대조군에 비해 각각 1.27, 1.58, 1.69, 1.49배 촉진되었으며, in viro 실험의 결과도 $10^{-5}$%사포닌 존재하에서 대조군에 비해 활성이 약 30% 증가하였다. 이상의 결과로 부터 인삼사포닌의 벼의 발아에 기능하는 amylase를 활성화하여, 벼의 발아 및 초기생장을 촉진하는 것으로 해석된다.

• 한국수산과학회지
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• 제53권1호
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• pp.132-138
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• 2020

Marphysa sanguinea is the most well-known polychaete species with a high economic value. However, this species has a high mortality in the early rearing stage of aquaculture. This study was conducted to find out the optimal substrate size and organic contents for the growth and survival rate of M. sanguinea larvae and juveniles. It was observed that the smaller grain size (<Ø 0.063 mm) and high organic contents (5-10%) induced settlement and reduced settlement time of larvae. Moreover, the growth and survival rate of larvae reached high levels at Ø 0.004-0.016 mm of grain sizes and 5-7.5% of organic contents as advantageous substrates for settlement. The survival rate of juveniles reached over 90% in less than Ø 0.016 mm substrate on 15-day experiment for different grain sizes of substrates. These results indicated that substrate compositions of less than Ø 0.016 mm of sand size and 5-7.5% of organic contents in mud will enhance the productivity of M. sanguinea at the early stage.

• Reproductive and Developmental Biology
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• 제38권1호
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• pp.21-34
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• 2014

The majority of early embryonic mortality in pregnancy occurs during the peri-implantation stage, suggesting that this period is important for conceptus viability and the establishment of pregnancy. Successful establishment of pregnancy in all mammalian species depends on the orchestrated molecular events that transpire at the conceptus-uterine interface during the peri-implantation period. This maternal-conceptus interaction is especially crucial in pigs because in them non-invasive epitheliochorial placentation occurs, in which the pre-implantation phase is prolonged. During the pre-implantation period, conceptus survival and the establishment of pregnancy are known to depend on the developing conceptus receiving an adequate supply of histotroph, which contains a wide range of nutrients and growth factors. Evidence links growth factors including epidermal growth factor (EGF), insulin-like growth factor-I (IGF-I), vascular endothelial growth factor (VEGF), and colony-stimulating factor 2 (CSF2) to embryogenesis or implantation in various mammalian species; however, in the case of pig, little is known about such functions of these growth factors, especially their regulatory mechanisms at the maternal-conceptus interface. Our research group has presented evidence for promising growth factors affecting cellular activities of primary porcine trophectoderm (pTr) cells, and we have identified potential intracellular signaling pathways responsible for the activities induced by these factors. Therefore, this review focuses on promising growth factors at the maternal-conceptus interface regulating the development of the porcine conceptus and playing pivotal roles in implantation events during early pregnancy in pigs.

• Journal of Plant Biology
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• 제18권4호
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• pp.155-160
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• 1975

Growth responses of lettuce seeds germinated in aqueous solutions of $SO_2$ were investigated for mode of action studies of this gas. The concentration and pH of $SO_2$ solution greatly affected the growth of germinating seeds. Root growth was more sensitive to $SO_2$ than hypocotyl growth. The sensitivity of total seedling growth lay between root and hypocotyl growth. Growth inhibition of germinating seeds appeared more serioius when $SO_2$ was added during the early stage of germination.

• 한국동물생명공학회지
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• 제34권2호
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• pp.123-129
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• 2019

Many transcription factors are involved in directing the growth of porcine oocytes. The localization and expression level of a given transcription factor often differ at each stage of early embryonic growth, which spans from fertilization to the formation of the blastocyst. A hallmark of the blastocyst stage is the separation of the endodermal and mesodermal ectoderm. The embryo's medium and its effects are known to be crucial during early development compared to the other developmental stages, and thus require a lot of caution. Therefore, in many experiments, early development is divided into the quality of oocyte and cumulus cells and used in experiments. We thought that we were also heavily influenced by genetic reasons. Here, we examined the expression patterns of five key transcription factors (CDX2, OCT4, SOX2, NANOG, and E-CADHERIN) during porcine oocyte development whose expression patterns are controversial in the pig to the literature. Antibodies against these transcription factors were used to determine the expression and localization of them during the early development of pig embryos. These results indicate that the expressions of key transcription factors are generally similar in mouse and pig early developing embryos, but NANOG and SOX2 expression appears to show speciesspecific differences between pig and mouse developing embryos. This work helps us better understand how the expression patterns of transcription factors translate into developmental effects and processes, and how the expression and localization of different transcription factors can crucially impact oocyte growth and downstream developmental processes.

• The Korean Journal of Physiology and Pharmacology
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• 제19권2호
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• pp.131-139
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• 2015

This study analyzed the differences in aerobic and anaerobic exercise ability and growth-related indicators, depending on the polymorphism of the ACE and the ACTN3 genes, to understand the genetic influence of exercise ability in the growth process of children. The subjects of the study consisted of elementary school students (n=856, age $10.32{\pm}0.07yr$). The anthropometric parameters, physical fitness and growth factors were compared among groups of the ACE I/D or the ACTN3 R577X polymorphisms. There were no significant differences between the anthropometric parameters, physical fitness and growth factors for the ACE gene ID or the ACTN3 gene R577X polymorphism. However, the DD type of ACE gene was highest in the side step test (p<0.05), and the DD type was significantly higher than the II+ID type (p<0.05) in the early bone age. The combined group of the ACE gene II+ID and the ACTN3 gene XX type significantly showed lower early bone age (p< 0.05). This study did not find any individual or compounding effects of the polymorphism in the ACE I/D or the ACTN3 R577X polymorphisms on the anthropometric parameters, physical fitness and growth factors of Korean children. However, the exercise experience and the DD type of the ACE gene may affect the early maturity of the bones.