• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.4
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• pp.303-329
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• 2019

Intestinal failure (IF) is the critical reduction of the gut mass or its function below the minimum needed to absorb nutrients and fluids required for adequate growth in children. Severe IF requires parenteral nutrition (PN). Pediatric IF is most commonly due to congenital or neonatal intestinal diseases or malformations divided into 3 groups: 1) reduced intestinal length and consequently reduced absorptive surface, such as in short bowel syndrome (SBS) or extensive aganglionosis; 2) abnormal development of the intestinal mucosa such as congenital diseases of enterocyte development; 3) extensive motility dysfunction such as chronic intestinal pseudo-obstruction syndromes. The leading cause of IF in childhood is the SBS. In clinical practice the degree of IF may be indirectly measured by the level of PN required for normal or catch up growth. Other indicators such as serum citrulline have not proven to be highly reliable prognostic factors in children. The last decades have allowed the development of highly sophisticated nutrient solutions consisting of optimal combinations of macronutrients and micronutrients as well as guidelines, promoting PN as a safe and efficient feeding technique. However, IF that requires long-term PN may be associated with various complications including infections, growth failure, metabolic disorders, and bone disease. IF Associated Liver Disease may be a limiting factor. However, changes in the global management of IF pediatric patients, especially since the setup of intestinal rehabilitation centres did change the prognosis thus limiting "nutritional failure" which is considered as a major indication for intestinal transplantation (ITx) or combined liver-ITx.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.3
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• pp.199-206
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• 2001

Behavior of nutrients along the salinity gradients in the Seomjin River estuary was investigated in March July, September and November, 1999. Sampling sites were set based on the surface salinity during each cruise rather than geographic locations. The results suggest that source of nitrate and silicate was the Seomjin River discharge, while that of nitrite and phosphate was waste disposal from the Gwangynng Bay near the mouth of Seomjin River estuary. Ammonia was supplied inside the estuary at the region about $6\~8$ km far from Nancho Island. Strong removal behavior of some nutrient such as ammonia, phosphate and silicate was observed at $5\~15$ psu salinity area in November, where high concentrations of $chlorophyll\;a\;(>8{\mu}g/L$) occurred. High N : P ratios and entirely removal of phosphate at chlorophyll a peak region suggest that phosphate is the limiting factor for phytoplankton growth. Relatively high ratios of Rb to Ra (Rb: Fluorescence before acidification, Ra: Fluorescence after acidification) at $5\~15$ psu salinity region in November indicate that phytoplankton were in good physiological condition.

• Mycobiology
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• v.30 no.3
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• pp.160-165
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• 2002

Aspergillus niger has been used as a host to express many heterologous proteins. It has been known that the presence of an- abundant protease is a limiting factor to express a heterologous protein. The protease deficient mutant of A. niger was obtained using UV-irradiation. A total of $1{\times}10^5$ spores were irradiated with $10{\sim}20%$ survival dose of UV, 600 $J/m^2$ at 280 nm, and the resulting spores were screened on the casein-gelatin plates. Ten putative protease deficient mutants showing the reduced halo area around colonies were further analyzed to differentiate the protease deficient mutant from other mutant types. Among ten putative mutants, seven mutants showed significant growth defect on nutrient rich medium and two mutants appeared to be the secretory mutants, which resulted in the impaired secretion of extracellular proteins including proteases. A mutant $pro^--20$ showed reduced halo zone without any notable changes in growth rate. In addition, the starchdegrading and glucose oxidase activities in the culture filtrate of $pro^--20$ mutant showed the similar range as that of the parental strain, which suggested that the $pro^--20$ mutant ought to be the protease deficient mutant rather than a secretory mutant. The reduced proteolytic activity of the $pro^--20$ was demonstrated using SDS-fibrin zymography gel. The reduced extracellular proteolysis was quantified by casein degradation assay and, comparing with the parental strain, less than 30% residual extracellular protease activity was detected in the culture filtrate of the $pro^--20$ mutant. The bio-activity of an exogenously supplemented hGM-CSF(human Granulocyte-Macrophage Colony Stimulating Factor) in the culture filtrate of $pro^--20$ mutant was detected until eight times more diluted preparations than that of the parental strain.

• Korean Journal of Environmental Agriculture
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• v.11 no.1
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• pp.20-25
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• 1992

To understand the fundamental features of reservoir environment and its future aspects, a simple predictive model for water quality was attempted with the aid of data easily obtained, Based on the data from 12 reservoirs in Korea, application of the simple predictive model was successfully made by means of statistical methods and simple physical submodels. Significant information on th effects of retention time on primary production in a reservoir, longitudinal change in water quality affected by certain non-dimensional parameters were also obtained. The chlorophyll-a concentration can be predicted by the equation as ; chlorophyll-a=($395{\time}limiting$ nutrient concentration) - 1.090.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.281-281
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• 2017

Recently, global warming by greenhouse gas effect is getting danger and danger for human life and agriculture at present. In Indonesia, according to heavy rain in the agriculture land is often covered by excess water in result crop growth would be affected negative. This water stress triggers roots failure in anaerobic condition for upland crop because of limiting roots respiration. Chili pepper grows in upland sometimes in touch with waterlogging due to rainfall and /or over flow water from river in Indonesia. In this case, roots growing is inhibited by effect of shortage of oxygen at root cap. Therefore, the objective of this study is to observe the plant behavior in waterlogging using mahor local genotypes (Ferosa, Laris, Romario) in Sumatra. The experiment was kept by at 1cm depth water above the soil surface as a waterlogged treatment for ---days. As a result, waterlogging affected plant growth of chili negatively, especially for roots growth. Almost roots were getting bad and changed color for brown during waterlogging. A significant negative effect for nutrient absorption by roots was found in dry weight of all varieties during waterlogging. Dry weight of roots was decreased by 81.4% and 67.6%, and those of aerial part decreased by 74% and 67.2% compared with control in Ferosa and Romario at 1week after treatment. On the other hand, dry weight of roots was decreased only 35% in Laris. Therefore, Laris has a tolerance for waterlogging compared to with other varieties. Also, Laris in SPAD value was kept initial level during waterlogging however those of Ferosa and Romario decreased. Finally, due to impact of waterlogging, it may be the roots become failure because of less aerenchyma formation under anaerobic condition. We need confirm aerenchyma formation morphologically in the future.

• Journal of Microbiology and Biotechnology
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• v.20 no.3
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• pp.602-608
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• 2010

An atrazine-degrading bacterium, strain KU001, was obtained from a sugarcane field at the Cane and Sugar Research and Development Center at the Kasetsart University, Kamphaeng Saen Campus, Thailand. Strain KU001 had a rod-to-coccus morphological cycle during growth. Biolog carbon source analysis indicated that the isolated bacterium was Arthrobacter histidinolovorans. Sequence analysis of the PCR product indicated that the 16S rRNA gene in strain KU001 was 99% identical to the same region in Arthrobacter sp. The atrazine degradation pathway in strain KU001 consisted of the catabolic genes trzN, atzB, and atzC. Strain KU001 was able to use atrazine as a sole nitrogen source for growth, and surprisingly, atrazine degradation was not inhibited in cells grown on ammonium, nitrate, or urea, as compared with cells cultivated on growth-limiting nitrogen sources. During the atrazine degradation process, the supplementation of nitrate completely inhibited atrazine degradation activity in strain KU001, whereas ammonium and urea had no effect on atrazine degradation activity. The addition of strain KU001 to sterile or nonsterile soils resulted in the disappearance of atrazine at a rate that was 4- to 5-fold more than that achieved by the indigenous microbial community. The addition of citrate to soils resulted in enhanced atrazine degradation, where 80% of atrazine disappeared within one day following nutrient supplementation.

• Journal of the Korean Society for Marine Environment & Energy
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• v.4 no.3
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• pp.3-15
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• 2001

The in situ observations and the seawater analyses were conducted for 3 years from August 1996 to August 1999 in order to elucidate and evaluate seasonal variations of marine water quality and trophic state in Mokpo harbour of Korea. Compared the seasonal seawater qualities of Mokpo harbour with the OECD standards of trophic classification in parameters such as Secchi depth, dissolved inorganic nitrogen, phosphate phosphorus and chlorophyll-a, the trophic level of seawater in Mokpo harbour was evaluated to be in mesotrophic or eutrophic state through all 4 seasons and to be in eutrophic state, particularly In summer. The estimation of pollution index by eutrophication showed the seawater quality of Mokpo harbour to deteriorate and fall under the regular grades through all 4 seasons, although the seawater quality of Mokpo harbour was evaluated to be equivalent to the second or third class of the Korean seawater quality standards in view of COD values. The results of eutrophication index estimation showed the high potentiality of red tide occurrence In Mokpo harbour, particularly in summer or fall. In the light of the average atomic ratio of N/P in seawater, the limiting nutrient factor against the growth of phytoplankton was concluded to be phosphorus rather than nitrogen in Mokpo Harbour.

• Korean Journal of Organic Agriculture
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• v.18 no.1
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• pp.83-92
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• 2010

Organic farming is a type of agricultural practices based on naturally occurring processes excluding or strictly limiting the use of synthetic fertilizers, pesticides, and other chemicals. This study was conducted to investigate the influences of agro-based materials, effective microorganisms (EM), liquid silicate (LS), and organic liquid fertilizer (OLF) for water dropwort (Oenanthe stolonifera DC.) cultivation. Soil pH, soil organic matter, and plant available phosphorous decreased with LS application. Exchangeable Ca and Mg decreased with EM application, and electrical conductivity and exchangeable Ca and K decreased with OLF application. Most of essential nutrient contents in water dropwort were reduced with the treatments of LS, EM, and OLF as compared with those in control plot, except nitrogen and phosphorus. However, diseases and insect pests were almost not observed in the water dropwort in the agro-based material application plots, except cluster caterpillar (Spodoptera litura). Productivity of water dropwort tended to be reduced: its higher productivity in the OLF and EM+LS plots and lower in the LS and control plots.

• Korean Journal of Ecology and Environment
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• v.42 no.4
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• pp.452-464
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• 2009

The objectives of this study were to evaluate spatial and temporal variability of water quality in 10 reservoirs and identify the key nutrients (N, P) influencing chlorophyll-a (CHL) along with analysis of empirical models and zonal patterns of total phosphorus (TP) and CHL. We analyzed total nitrogen (TN), TP, CHL, water clarity (Secchi depth, SD), and evaluated potential limiting nutrient using ambient N:P ratios and previous criteria of ambient nutrients. Water clarity and CHL varied largely depending on the seasonal monsoon and type of reservoir, but trophic state was diagnosed as eutrophy, base on mean CHL in most reservoirs. The peak of TP did not match the contents of CHL due to rapid flushing during the high run-off period. In the reservoir of DR, regression coefficient in the $P_r$ was 0.510 but was 0.159 in the $M_o$, while the TP-CHL relation in the YR increased during the monsoon compared to the premonsoon. The regression coefficient in the $P_r$ was not statistically significant but the value of $M_o$ was 0.250. TP showed similar longitudinal zonal gradients among the reservoirs of DR, YR and JR. Empirical models of TP-CHL, based on overall data, showed that CHL was determined by phosphorus($R^2=0.244$, p=0.0019). Regression analysis of CHL-SD showed a stronger linear fit ($R^2=0.638$, p<0.001) than the TP-CHL model.

• ALGAE
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• v.23 no.4
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• pp.277-288
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• 2008

The relationship between nutrients and phytoplankton dynamics was investigated daily from 12 April to 22 July 2003 in Sagami Bay, Japan. According to multidimensional scaling (MDS) and cluster analysis, phytoplankton community was divided into four distinct groups. The first group was consisted of centric diatom species, such as Guinardia spp., Detonula spp., Letocylindrus danicus, Skeletonema costatum, Eucampia zodiacus and Chaetoceros spp.. The second and third clusters comprised mainly diatoms and dinoflagellates, respectively. The other cluster was restricted to the samples collected during the last sampling period when the rainfall and river discharge was frequently recorded. Canonical correspondence analysis (CCA) was applied to analyze four groups respectively, which focused on the effects of nutrients concentration and ratio on phytoplankton variations. Based on CCA analysis, most species of centric diatom were negatively correlated with DSi concentrations and Si/N ratio. Nutrients were strongly limited phytoplankton growth during the summer when the rainfall was not observed, whereas river discharge by rainfall and counterclockwise coastal currents (although the surface circulation pattern is often altered by Kuroshio Current, the counterclockwise coastal currents are generally dominant) has brought phytoplankton population accumulation and triggered the micoalgae growth in western part of the bay. Phosphorous (P) was strongly limited after significantly increases in the phytoplankton abundances. However, silicate (Si) was not a major limiting factor for phytoplankton production, since Si/DIN and Si/P ratio did not create any potential stoichiometric limitation. This indicates that high Si availability contributes favorably to the maintenance of diatom ecosystems in Sagami Bay.