• The korean journal of orthodontics
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• v.20 no.3 s.32
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• pp.427-446
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• 1990

The objective of this study was to understand the major changes of craniofacial dimensions and spatial growth pattern during the late embryonic and fetal period of human fetures. This study was performed with the selective materials of normal fetuses received from the Registry of Congenital Malformation of Seoul National University Hospital. The specimens consisted of nineteen embryos and sixty-six fetuses. The photomicrographs from mid-segittal sections of embryos were used for angular measurement, and the lateral cephalograms taken with soft X-ray were also measured in liners and angular aspects. All of the anatomical landmarks for the tracing of the photomicrographs and cephalograms were referred to the previous reports on literature. The sequential changes of prenatal craniofacial dimensions and agles were analysed statistically and discussed on the focus about the developmental growth directions of human ore-facial structure arised from heterogeneous origins. The results are as follows, 1) Cranial base angle was almost formed at about 6 weeks old embryos with the average angle of $127.4{\pm}6.33^{\circ}$ (n=3) and it was almost constant onwards. 2) The linear increase rates of anterior cranial base length and anterior facial height exceeded those of the posterior cranial base length and posterior facial height, and the maxilla grows more rapidly on the horizontal dimension than the vertical dmension during the fetal period. 3) The angular relationship between the anterior cranial base and palatal plane decreasedslightly during the fetal period, disclosing $11^{\circ}$ at 12th week gestation and $5^{\circ}$ at 41th weeks gestation. 4) Genial angle was maintained almost constantly at about $130^{\circ}$ during the fetal period from 12 weeks to 41 weeks of gestation.

• The Korean Journal of Mycology
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• v.42 no.4
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• pp.322-327
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• 2014

Subculture is the most common method for preservation fungi, but has a disadvantage of accumulation of spontaneous mutations during the repeated subculture. To reduce the subculture frequency, the effect of preservation period at $4^{\circ}C$ in a slant culture was examined on the mycelia growth and lignocellulolytic enzyme activities of various basidiomycetes. Mushrooms, including Stereum ostrea, Coprinellus micaeus, Trametes versicolor, Hypholoma fasciculare, Wolfiporia extensa, Pleurotus pulmonarius, Piptoporus betulinus and Ganoderma applanatum were not affected by the preservation period more than two years, indicating that they can be maintained by subculture every two years. Some other tested fungal strains showed a significant decrease in both viability and enzyme activity when they were maintained for two years, suggesting that they should be subcultured at least once in a year. A little correlation was found between the recovery of mycelial growth and extracellular enzyme activity. In conclusion, mycelial activity and enzyme activity according to storage period is expected to be a way of deciding on subculture times for fungal preservation.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.674-683
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• 2017

The frequency and intensity of soil moisture stress associated with climate change has increasing, and the stability of field crop cultivation has decreasing. This experiment was conducted to investigate the effect of soil moisture management method on growth and yield of corn. Soil moisture was managed at the grade of WSM (wet soil moisture, 34.0~42.9%), OSM (optimum soil moisture, 27.8~34.0%), DSM (dry soil moisture, 20.3~27.8%), and ESM (extreme dry moisture, 16.6~20.3%) during V8 (8th leaf stage)-VT (tasseling stage). After VT, irrigation was limited. The treated amount of irrigation was 54.1, 47.7, 44.0 and 34.5% of total water requirement, respectively. The potential evapotranspiration during the growing period was $3.29mm\;day^{-1}$, and upward movement of soil water was estimated by the AFKAE 0.5 model in the order of ESM, DSM, OSM, and WSM. We could confirm this phenomenon from actual observations. There was no significant difference in leaf characteristics, dry matter, and primary productivity depending on the level of soil moisture, but leaf development was delayed and dry weight decreased in DSM. However, dry weight and individual productivity of DSM increased after irrigation withdrawal compared to that of OSM. In DSM, ear yield and number of kernels per ear decreased, but water use efficiency and harvest index were higher than other treatments. Therefore, it is considered that the soil moisture is concentratedly managed before the V8 period, the V8-VT period is controlled within the range of 100 to 500 kPa (20.3~27.8%), and no additional irrigation is required after the VT.

• Journal of the Korean Wood Science and Technology
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• v.47 no.3
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• pp.360-370
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• 2019

Woody crops cultivated in short-rotation coppices are attractive sources of lignocellulosic materials for bioethanol production, since they are some of the most abundant renewable resources. In this study, we evaluated the effects of the growth period on bioethanol production using short-rotation woody crops (Populus nigra ${\times}$ Populus maxiwiczii, Populus euramericana, Populus alba ${\times}$ Populus glandulosa, and Salix alba). The carbohydrate contents of 3-year-old and 12-year-old short-rotation woody crop branches were 62.1-68.5% and 64.0-67.1%, respectively. The chemical compositions of 3-year-old and 12-year-old short-rotation woody crop branches did not vary significantly depending upon the growth period. However, the 3-year-old short-rotation woody crop branches (glucose conversion: 26-40%) were hydrolyzed more easily than their 12-year-old counterparts (glucose conversion: 19-24%). Furthermore, following the fermentation of enzymatic hydrolysates from the crop branch samples (by Saccharomyces cerevisiae KCTC 7296) to ethanol, the ethanol concentration of short rotation coppice woody crops was found to be higher in the 3-year-old branch samples (~ 0.18 g/g dry matter) than in the 12-year-old branch samples (~ 0.14 g/g dry matter). These results suggest that immature wood (3-year-old branches) from short-rotation woody crops could be a promising feedstock for bioethanol production.

• Animal Bioscience
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• v.34 no.1
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• pp.102-108
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• 2021

Objective: The objective of this study was to investigate the influence of dietary lead (Pb) supplementation and feeding period on growth performance, organ weight, and Pb accumulation in pigs. Methods: In a 56-day feeding experiment, a total of 48 barrows with initial body weight 10.4±0.6 kg were allotted to 2 dietary treatments (0 and 200 mg/kg of supplemental Pb) in a completely randomized design with 6 replicates. Body weight and feed intake were recorded to calculate growth performance. At the end of each 14 day-period (on days 14, 28, 42, and 56), an animal was randomly selected from each pen and slaughtered to collect blood samples, hair samples, left 5th rib, heart, liver, kidneys, lungs, and longissimus dorsi muscle samples. Results: Average daily gain and average daily feed intake were reduced (p<0.05) by supplemental Pb during the day 42 to 56. Relative kidney weight to body weight was linearly increased with increasing feeding period in pigs fed the Pb-supplemented diet, but not in pigs fed the control diet (p<0.05). The Pb concentrations in hair, left 5th rib, kidneys, and lungs were linearly increased with longer feeding period in pigs fed the Pb-supplemented diet, but not in pigs fed the control diet (p<0.01). Conclusion: Dietary Pb supplementation caused growth retardation and Pb accumulation in most organs, particularly in hair, bone, and kidneys in a time-dependent manner.

• Development and Reproduction
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• v.27 no.3
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• pp.101-115
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• 2023

Environmental factors impact oyster growth, condition, and gonadal development, which is linked to gamete characteristics observed through histology. The reproductive cycle of bivalves is related to energy storage and utilization. Therefore, in this study, the year-round growth change and gonadal development of oysters were observed using histological analysis, and the biochemical composition changes were confirmed. The oysters used in this study are being nurtured in Gadeok-do, and 40 oysters were randomly sampled monthly from March 2021 to February 2022. Result of histological analysis of gonads, oysters were showed early development from December to February, late development from March and April, mature and ripe from May to July, spawned from August to October, and spent from November to December. Condition index values of oysters decreased in summer and autumn and increased again when entered the spent after spawning. The protein content of oysters was high in May, the maturity period, and the lipid content decreased during the spawning period. In addition, EPA and DHA, the major fatty acids of oysters, were low during the spawning period and high during the maturation period. As a result, this study suggested a close relationship between changes in oyster growth, biochemical composition, and the reproductive cycle.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.4
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• pp.295-303
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• 1990

In this study, drought period when important agronomic characters of sesame plant is critical, was examined at different growth stages. Plant death by drought started at 40 days after drought in vegetative growth stage and 20 days, in reproductive growth stage. Obserbed by growth stage, drought damage in reproductive growth stage was more in jurious than vegetative growth stage. All the important agronomic characters was refreshed until 40 days and 20 days after drought in vegetative growth stage and reproductive growth stage respectively, but it could berefreshed after those times. Decrease rate of yield by drought ranged from 29 to 80% in vegetative growth stage and from 49 to 85% in respective growth stage. All the important agronomic characters except rate of ripeness showed positive association with grain yield under drought condition. Oil content in grain was decreaced by drought but composition of fatty acid was not affected by it.

• Journal of Ecology and Environment
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• v.34 no.2
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• pp.193-202
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• 2011

We studied temperature sensitivity characteristics of soil respiration during periods of rising and falling temperatures within a common temperature range. We measured soil respiration continuously through two periods (a period of falling temperature, from August 7, 2003 to October 13, 2003; and a period of rising temperature from May 2, 2004 to July 2, 2004) using an open-top chamber technique. A clear exponential relationship was observed between soil temperature and soil respiration rate during both periods. However, the effects of soil water content were not significant, because the humid monsoon climate prevented soil drought, which would otherwise have limited soil respiration. We analyzed temperature sensitivity using the $Q_{10}$ value and $R_{ref}$ (reference respiration at the average temperature for the observation period) and found that these values tended to be higher during the period of rising temperature than during the period of falling temperature. In the absence of an effect on soil water content, several other factors could explain this phenomenon. Here, we discuss the factors that control temperature sensitivity of soil respiration during periods of rising and falling temperature, such as root respiration, root growth, root exudates, and litter supply. We also discuss how the contribution of these factors may vary due to different growth states or due to the effects of the previous season, despite a similar temperature range.

• Journal of Forest and Environmental Science
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• v.28 no.1
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• pp.12-18
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• 2012

Like any other natural resources, forest flora may experience the extreme threat of elevated temperature and saline water submergence at different stages of their lives i.e. from germination to maturity due to climate change effects. The overall aim of the study was to measure the effect of higher temperatures along with saline water irrigation on survival and initial growth during seedling stage of Artocarpus chapalasha. The experiment was conducted in temperature- humidity-photoperiod regulated plant growth chamber during stipulated period to measure the growth performance of randomly selected seedlings. Within three different elevated temperatures viz. $30^{\circ}C$, $32^{\circ}C$ and $34^{\circ}C$, the seedlings were given three different saline conditions such as 0.5 g/L, 1.5 g/L and 2.5 g/L NaCl concentrations. Results found from the experiment was that, seedlings of Artocarpus chaplasha reared at different temperatures and saline water treatments showed stunted growth than reared at existing outdoor temperature ($26.31^{\circ}C$) irrigated with regular fresh water. Seedling growth at three different parameters such as height, collar diameter and number of leaves showed that with increasing temperature individuals respond negatively to increasing saline condition. The seedling's growth occurred at every day in height, collar diameter and leaf. However, growth rate reduced later during the observation. The combined effect of high salinity and higher elevated temperature results in seedling mortality. Therefore, Artocarpus chaplasha may not thrive at higher temperature and salinity intrusion at its early growing period in plantation and natural forest areas.

• Journal of Information Science Theory and Practice
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• v.3 no.3
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• pp.45-63
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• 2015

The word ‘growth’ represents an increase in actual size, implying a change of state. In science and technology, growth may imply an increase in number of institutions, scientists, or publications, etc. The present study demonstrates the growth of neurology literature for the period 1961-2010. A total of 291,702 records were extracted from the Science Direct Database for fifty years. The Relative Growth Rate (RGR) and Doubling Time (Dt.) of neurology literature have been calculated, supplementing with different growth patterns to check whether neurology literature fits exponential, linear, or logistic models. The results of the study indicate that the growth of literature in neurology does not follow the linear, or logistic growth model. However, it follows closely the exponential growth model. The study concludes that there has been a consistent trend towards increased growth of literature in the field of neurology.