• Title/Summary/Keyword: Stages of growth

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NELL2 Function in Axon Development of Hippocampal Neurons

  • Kim, Han Rae;Kim, Dong Hee;An, Ji Young;Kang, Dasol;Park, Jeong Woo;Hwang, Eun Mi;Seo, Eun Jin;Jang, Il Ho;Ha, Chang Man;Lee, Byung Ju
    • Molecules and Cells
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    • v.43 no.6
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    • pp.581-589
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    • 2020
  • Neurons have multiple dendrites and single axon. This neuronal polarity is gradually established during early processes of neuronal differentiation: generation of multiple neurites (stages 1-2); differentiation (stage 3) and maturation (stages 4-5) of an axon and dendrites. In this study, we demonstrated that the neuron-specific n-glycosylated protein NELL2 is important for neuronal polarization and axon growth using cultured rat embryonic hippocampal neurons. Endogenous NELL2 expression was gradually increased in parallel with the progression of developmental stages of hippocampal neurons, and overexpression of NELL2 stimulated neuronal polarization and axon growth. In line with these results, knockdown of NELL2 expression resulted in deterioration of neuronal development, including inhibition of neuronal development progression, decreased axon growth and increased axon branching. Inhibitor against extracellular signal-regulated kinase (ERK) dramatically inhibited NELL2-induced progression of neuronal development and axon growth. These results suggest that NELL2 is an important regulator for the morphological development for neuronal polarization and axon growth.

Genetic Analysis of Pre-weaning and Post-weaning Growth Traits of Mecheri Sheep under Dry Land Farming Conditions

  • Thiruvenkadan, A.K.;Karunanithi, K.;Muralidharan, J.;Babu, R. Narendra
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.8
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    • pp.1041-1047
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    • 2011
  • Data on 2,365 Mecheri sheep (1,201 males and 1,164 females), maintained at the Mecheri Sheep Research Station, Pottaneri, India, and recorded between 1979 and 2006, were analysed to study the growth related traits and their genetic control. The body weights at different ages (i.e. at birth, weaning (3 months), 6, 9 and 12 months) were recorded and collected from the birth and growth registers maintained in the farm. The average weights of Mecheri sheep at birth, and at 12 months of age were $2.24{\pm}0.01$ and $16.81{\pm}0.15$ kg respectively. The pre- and post-weaning average daily weight gains were $63.84{\pm}0.75$ and $29.52{\pm}0.43$ g respectively. Study revealed a significant difference with the period of lambing on body weight, weight gain and efficiency in weight gain at different stages of growth. Males were heavier and had a higher weight gain than females at almost all stages of growth and the differences tended to increase with age. The direct heritability estimates increased from birth to six months of age and then decreased. The direct heritabilities of all body weights at different stages of growth were low to moderate in magnitude and the values at birth, weaning, six, nine and 12 months of age were 0.08, 0.17, 0.21, 0.13 and 0.10 respectively. For the estimation of heritability at birth and three months body weights, the direct additive genetic and maternal additive genetic effects have to be taken into account and for the estimation of six months weight, the direct additive genetic and maternal permanent environmental effects have to be included in the model. The estimates of heritability, phenotypic and genetic correlations among the different body weights indicated that the selection for improving the body weights at different traits should be done on the basis of three or six months weight because of higher heritability estimates and having higher genetic correlations with other traits.

Studies on Growth Responses and Yields of Panax ginseng C. A. Meyer Grown under Hydroponic Culture with different Temperatures and Growth Stages (온도 및 생육시기에 따른 수경재배 인삼의 생장특성과 수량에 관한 연구)

  • Lee, Gyeong-A;Chang, Yoon-Kee;Park, Seong-Yong;Kim, Gyeong-Ae;Kim, Sun-Ho;Song, Beom-Heon
    • Korean Journal of Medicinal Crop Science
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    • v.20 no.3
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    • pp.184-189
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    • 2012
  • This study was carried out to have the basic and applied informations relating to increase the productivity and quality of ginseng. 2 years-old ginseng was cultivated under hydroponic culture with the controlled environment conditions in a greenhouse. Major growth characters and yields were investigated with two different temperatures and several growth stages. The plant height and stem diameter were higher at low temperature than those at high temperature. They were not clearly different with six different growth stages. The root length was not clearly different between two temperatures; however it was continuously grown from June until August. The root diameter was higher at low temperature than that at high temperature. It was rapidly increased from June until August. The length, width, and area of leaf were higher at low temperature than those at high temperature. The fresh and dry weights of different plant tissues were also heavier at low temperature than those at high temperature. The moisture content of ginseng root was continuously decreased from June until August. The yield of ginseng was higher at low temperature compared to that at high temperature. The cultivating conditions in hydroponic culture of ginseng, especially temperature, would be an important factor to have better growth and production.

Effects of Ridge Height in Dry Paddy Field on Growth and Seed Yield of Soybean Cultivars

  • Seong, Rak-Chun;Park, Sei-Joon;Shim, Sang-In
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.45 no.2
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    • pp.88-92
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    • 2000
  • Excessive soil water in paddy field induces growth losses during the vegetative stages of soybean plants. Our objectives were to know growth responses of soybean as affected by the level of ridge heights. A field experiment was conducted at the Research Farm of Korea University near Seoul in 1996. Ten cultivars of soybean (Glycine max (L.) Merrill) were planted at the ridge heights of 10, 30, and 50cm in paddy soil on 27 June. Total dry matter accumulation at the 10cm ridge height was severely decreased until the growth stage of R5 as compared to the ridge heights of 30 and 50cm, and this decrement was mainly due to both reduced leaf and stem dry weights. However, seed dry weight was not significantly decreased at the lower ridge height with the increment of harvest index. Cultivar differences were found on seed dry weight, crop growth rate from R1 to R5, and leaf/stem ratio of R5. From the above results, soybean growth responses to excessive soil water in paddy field were different between seed filling stage and late vegetative to early reproductive growth stages.

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Changes in the Activities of Certain Enzymes in Tobacco Leaf (Nicotiana tabacum) during Growth (연초엽조직의 물질대사에 관여하는 몇가지 효소활성에 관하여)

  • 김준철;윤경은;강서규
    • Journal of the Korean Society of Tobacco Science
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    • v.4 no.1
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    • pp.1-5
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    • 1982
  • The metabolic enzymes, nitrate reductase, amylase and peroxidase and the Photorespiratory enzyme, Slycolate oxidise in Nicotiana tabacum varieties were studied at various growth stages. The enzyme activities of young leaves with rapid growth were different from those of old ones with stationary growth. In young leaves, activity of nitrate reductase was higher than that in mature ones and amylase activity was fairly constant in all stages. Activities of glycolate oxidise and peroxidase were found to be significantly lower in young leaves than in mature ones. Activity of glycolate oxidase in mature middle leaves was 2.45 times higher than that of young ones and inhibited by 36% when the enzyme was treated with 0.16 mM isonicotinic hydrazide.

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The Difference Analysis between Maturity Stages of Venture Firms by Classification Techniques of Big Data (빅데이터 분류 기법에 따른 벤처 기업의 성장 단계별 차이 분석)

  • Jung, Byoungho
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.15 no.4
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    • pp.197-212
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    • 2019
  • The purpose of this study is to identify the maturity stages of venture firms through classification analysis, which is widely used as a big data technique. Venture companies should develop a competitive advantage in the market. And the maturity stage of a company can be classified into five stages. I will analyze a difference in the growth stage of venture firms between the survey response and the statistical classification methods. The firm growth level distinguished five stages and was divided into the period of start-up and declines. A classification method of big data uses popularly k-mean cluster analysis, hierarchical cluster analysis, artificial neural network, and decision tree analysis. I used variables that asset increase, capital increase, sales increase, operating profit increase, R&D investment increase, operation period and retirement number. The research results, each big data analysis technique showed a large difference of samples sized in the group. In particular, the decision tree and neural networks' methods were classified as three groups rather than five groups. The groups size of all classification analysis was all different by the big data analysis methods. Furthermore, according to the variables' selection and the sample size may be dissimilar results. Also, each classed group showed a number of competitive differences. The research implication is that an analysts need to interpret statistics through management theory in order to interpret classification of big data results correctly. In addition, the choice of classification analysis should be determined by considering not only management theory but also practical experience. Finally, the growth of venture firms needs to be examined by time-series analysis and closely monitored by individual firms. And, future research will need to include significant variables of the company's maturity stages.

An Empirical Study on High-technology Innovative SMEs' Characteristics and their Bottlenecks across the Growth Stages (기술혁신형 중소기업의 특성과 성장단계에 따른 애로요인의 실증적 연구)

  • Chang, Young-Soon;Kim, Ju-Mi
    • IE interfaces
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    • v.20 no.3
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    • pp.418-426
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    • 2007
  • This study is to suggest the government's support direction for the small and medium sized enterprises (SMEs) by examining the relations among technology level, innovation factors, entrepreneur's characteristics, and start-up reasons. The management bottlenecks and the necessary fields of government's support are also investigated across the company's growth stages. Empirical analysis was conducted based on the 318 Korean SMEs' data receiving the Venture and/or Inno-biz certification. Results show that managing difficulties of the company have typical pattern according to the stage of growth. The characteristics of an entrepreneur such as age, education background and past experience affect the early stage of starting business. We also found that the technology level is closely connected with operational innovation activities and circumstances, entrepreneur's characteristics, start-up motives, and technological innovation activities.

Studies on the Physiological and Biochemical Mechanisms of the Drought Resistance in Winter Barley (대맥한발저항성 기작에 관한 생리적 및 생화학적 연구)

  • 최원열;김용환
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.28 no.4
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    • pp.451-457
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    • 1983
  • This study was conducted to estimate the effect of the drought on the changes of chlorophyll, protein and proline content of upper three leaves, and the grain yield components of barley plant (CV. baegdong) subjected to water stress at four stages: late vegetative, boot, anthesis early grain filling. 1. In comparison with leaf posititions in water stress, the first leaf below flag leaf maintained the highest relative turgidity, chlorophyll and protein content and showed the least proline accumulation. And, in terms of growth stages in water stress, chlorophyll was shown to be highest at anthesis stage, protein being highest at boot stage and proline being least at boot stage. 2. In boot stages, culm and spike length, and Number of grains per spike were remarkably decreased. And the weight of 1000 grains was at least level in the early grain filling stage, and also the grain size was comparatively decreased at boot and two following stages. 3. The protein content of grain by water stress, apart from early grain filling stage, was not significantly affected by water stress at different growth stages. 4. The rate of sterility was particularly increased at boot and anthesis stages. 5. It was eventually concluded that the boot stage among four growth stages, and the flag leaf in 3 leaf positions were mostly damaged by water stress at reproductive growth stage.

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Developmental Proteomic Profiling of Porcine Skeletal Muscle during Postnatal Development

  • Kim, Nam-Kuk;Lim, Jong-Hyun;Song, Min-Jin;Kim, Oun-Hyun;Park, Beom-Young;Kim, Myung-Jick;Hwang, In-Ho;Lee, Chang-Soo
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.10
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    • pp.1612-1617
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    • 2007
  • In this study, we have compared the skeletal muscle proteome at various stages of porcine postnatal development. Korean native pigs were divided into five postnatal stages of 30, 70, 130, 170 and 300 d and their loin muscles were analyzed for muscle proteome by using two-dimensional electrophoresis and mass spectrometry. We found 5 proteins showing a consistent pattern during skeletal muscle growth. Four proteins were identified as myosin light chain 1 slow-twitch (MLC1sa) isoform, troponin T, triosephosphate isomerase (TIP) and DJ-1 protein. The remaining protein was not identified. Two muscle fiber proteins of MLC1sa isoform and troponin T showed a high expression level at an early postnatal stage and then their levels were decreased markedly during growth stages. On the other hand, the expression of TIP and DJ-1 protein, which are well known as catalysis enzyme and antioxidant-related protein, respectively, were linearly increased during growth stages. Thus, the stage-related muscle proteins may be useful as parameters for understanding the developmental characteristics of biochemical and physiological properties in Korean native pig skeletal muscle.

Analysis of the Volatile Flavor Compounds Produced during the Growth Stages of the Shiitake Mushrooms (Lentinus edodes)

  • Cho, Duk-Bong;Seo, Hye-Young;Kim, Kyong-Su
    • Preventive Nutrition and Food Science
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    • v.8 no.4
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    • pp.306-314
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    • 2003
  • Volatile flavor components, produced during the young (P-1), immature (P-2), mature (P-3) and old (P-4) growth stages, of shiitake mushrooms (Lentinus edodes), were extracted by simultaneous steam distillation and extraction (SDE), using a mixture of n-pentane and diethyl ether (1:1, v/v) as the extraction solvent. Analyses of the concentrates, by capillary gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS), led to the identification of 129, 129, 111 and 120 components in the P-1, 2, 3 and 4 stages, respectively. The major volatile compounds were l-octen-3-o1, 3-octanol, 3-octanone and 4-octen-3-one. Ethanol and ethyl acetate were also detected in large amounts. The characteristic volatile compounds found in shiitake mushrooms, such as dimethyl disulfide, dimethyl trisulfide and 1, 2, 4-thiolane, were at low concentrations in all samples. The amount of l-octen-3-o1 decreased as growth progressed, but concentrations of 3-octanone increased. The amount of 4-octen-3-ol decreased from P-1 to P-3, but was at a high concentrations in P-4. The concentration of 3-octanol gradually increased and reached its highest concentration in P-3, but decreased in P-4. The C8-compounds comprised 70.91, 64.09, 64.29 and 60.01 % in the P-1, 2, 3 and 4 stages, respectively, so decreased gradually with growth. The S-compounds were found in the highest concentrations in P-3.