• Journal of Korean Society of Water and Wastewater
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• v.36 no.2
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• pp.81-95
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• 2022

The present study was performed to investigate the effects of NH₃-N and nitrifying microorganisms on the increased BOD of downstream of the Yeongsan river in Gwangju. Water samples were collected periodically from the 13 sampling sites of rivers from April to October 2021 to monitor water qualities. In addition, the trends of nitrogenous biochemical oxygen demand (NBOD) and microbial clusters were analyzed by adding different NH₃-N concentrations to the water samples. The monitoring results showed that NH₃-N concentration in the Yeongsan river was 22 times increased after the inflow of discharged water from the Gwangju 1st public sewage treatment plant (G-1-PSTP). Increased NH₃-N elevated NBOD levels through the nitrification process in the river, consequently, it would attribute to the increase of BOD in the Yeongsan river. Meanwhile, there was no proportional relation between NBOD and NH₃-N concentrations. However, there was a significant difference in NBOD occurrence by sampling sites. Specifically, when 5 mg/L NH₃-N was added, NBOD of the river sample showed 2-4 times higher values after the inflow of discharged water from G-1-PSTP. Therefore, it could be thought other factors such as microorganisms influence the elevated NBOD levels. Through next-generation sequencing analysis, nitrifying microorganisms such as Nitrosomonas, Nitroga, and Nitrospira (Genus) were detected in rivers samples, especially, the proportion of them was the highest in river samples after the inflow of discharged water from G-1-PSTP. These results indicated the effects of nitrifying microorganisms and NH₃-N concentrations as important limiting factors on the increased NBOD levels in the rivers. Taken together, comprehensive strategies are needed not only to reduce the NH₃-N concentration of discharged water but also to control discharged nitrifying microorganisms to effectively reduce the NBOD levels in the downstream of the Yeongsan river where discharged water from G-1-PSTP flows.

• Environmental Engineering Research
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• v.14 no.4
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• pp.220-225
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• 2009

The water quality in eutrophic lakes is affected by serious problems, such as abnormal increasing of Cyanobacteria. The purpose of this study was to investigate the possibility of a modified flotation system using a hybrid technique formed by chemical compounds and an electrostatic bridge. Therefore, experiments using the hybrid technique were performed to measure the zeta potential value on the phytoplankton surface and the removal efficiencies of phytoplankton, ammonia nitrogen, nitrate nitrogen and phosphoric acid. The results were as follows: Firstly, the zeta potential of M.aeruginosa was observed to approach charge neutralization due to adhesion of magnesium hydroxide precipitate on the phytoplankton surface in the pH range 10.5 to 11. Secondly, the concentration of chlorophyll-a decreased from about 150 to 20${\mu}g$g/L, with a maximum removal efficiency of 84% due to coagulation with pH values higher than 10. Thirdly, the N$H_4$-N concentration was observed to decrease from 0.62 to 0.54mg-N/L (13%), and the P$O_4$-P concentration, which is a limiting factor to the formation of algae blooms, decreased from 0.27 to 0.02mg-P/L (92%). These findings suggest that the modified flotation system can be applied for the purification of the raw water of numerous lakes containing high phytoplankton populations and elevated pH.

• Journal of Environmental Science International
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• v.12 no.10
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• pp.1085-1093
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• 2003

This study was conducted to investigate anoxic-RBC (rotating biological contactor) and its application in advanced municipal wastewater treatment process to remove biologically organics and ammonia nitrogen. Effluent COD and nitrogen concentration increased as the increase of volumetric loading rate. But, the concentration changes of NO$_2$$\^$-/ -N and NO$_3$$\^$-/ -N were little, as compared to COD and NH$_4$$\^$+/ -N. When the volumetric loading rate increased, COD removal efficiency and nitrification appeared very high as 96.7∼98.8% and 92.5∼98.8%, respectively. However, denitrification rate decreased to 76.2∼88.0%. These results showed that the change of volumetric loading rate affected to the denitrification rate more than COD removal efficiency or nitrification rate. The surface loading rates applied to RBC were 0.13～6.0lg COD/㎡-day and 0.312∼1.677g NH$_4$$\^$+/-N㎡-day and they were increased as the increase of volumetric loading rate. However, the nitrification rate showed higher than 90%. The thickness of the biofilm in RBC was 0.130 ∼0.141mm and the density of biofilm was 79.62∼83.78mg/㎤. They were increased as surface loading rate increased. From batch kinetic tests, the k$\_$maxH/ and k$\_$maxN/ were obtained as 1.586 g C/g VSS-day, and 0.276 g N/g VSS-day, respectively. Kinetic constants of denitrifer in anoxic reactor, Y, k$\_$e/, K$\_$s/, and k were 0.678 mg VSS/mg N, 0.0032 day$\^$-1/, 29.0 mg N/l , and 0.108 day$\^$-l/, respectively. P and K$\_$s/, values of nitrification and organics removal in RBC were 0.556 g N/㎡-day and 18.71 g COD/㎡-day, respectively.

• Textile Coloration and Finishing
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• v.13 no.6
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• pp.9-9
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• 2001

The preparations of deodorizing fibers using metalloporphyrines have been investigated. The three metalloporphyrin derivatives(MTCPP, M=Mn, Zn, Sn) were prepared in modest to good yields. The metalloporphyrin derivative as a deodorant material was introduced to fibers by a dyeing method. The deodorant activity(D.A.) of these deodorizing fibers was measured by chromogenic gas detector tubes. In comparison with untreated fiber, these deodorizing fibers was remarkably effective against NH₃ and CH₃SH. More than 98% of ammonia can be removed within 20 min.. The D.A.(%) of fiber adsorbed MTCPP was more than 80% after 90min..

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.2
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• pp.267-274
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• 1992

In order to study the relationships between the contents of urinary nitrogenous compounds and energy utilization of bird, the sum of nitrogen contents of uric acid, ammonia, creatine and urea voided in excreta was estimated as the urinary nitrogen (UN) in 13-33 day-old fed or fasted White Leghorn male chicks. Energy retention and heat production of birds were determined by comparative slaughter studies. 2.75 mg of endogenous urinary nitrogen (EUn) and 2.19 mg of uric acid was excreted constantly per kJ heat production in fasted bird. One mg of UN was proportionated to 32.26 J (r = 0.999, n = 8) of the urinary energy (UE) in fed and 32.97 J (r = 0.9998, n = 8) of the endogenous urinary energy (UEn) in the fasted bird. Also relationships between 1 mg of uric acid and 38.95 J of UE (r = 0.998, n = 8) or 38.97 J of UEe (r = 0.996, n = 8) were significant (p<0.01). The EUn (r = 0.997, n = 4), uric acid (r = 0.995, n = 4) and metabolic fecal energy (FEm) plus UEe (r = 0.961, n = 4) were increased with the increase of body weight (g/bird). Metabolic fecal nitrogen (MFn) or energy (FEm), EUn and UEe per unit diet were not influenced by the age of day or body weight. The results indicated that energy and protein utilization of bird can be approximated by the relationships among urinary nitrogen, urinary energy, uric acid content in excreta and body weight of bird.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.3
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• pp.174-178
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• 2009

Many radiopharmaceuticals have been developed and wildy used in the imaging cardiac function. Myocardial perfusion imaging (MPI) is a well established noninvasive method of assessing coronary blood flow and has been widely used in patients diagnosed or suspected with coronary artery diseases. The innovation of radiopharmaceuticals used in the cardiac imaging is one of the most important contributors to the development of nuclear cardiology. Thallium-201 and various technetium-99m agents have been globally used for myocardial perfusion SPEG, and N-13 ammonia (13NH3), rubidium-82 (82Rb), 0-15 water (H2150) for myocardial perfusion PET. As well as the cardiac perfusion studies, new radiopharmaceuticals that visualize fat metabolism or receptors of the sympathetic nervous system have successfully been applied to clinical practice. Useful information can be obtained for diagnosing coronary artery disease, evaluating patients' condition, or assessing therapeutic effects. In this review, we describe the characteristics and clinical usefulness of radiopharmaceuticals used for cardiac SPEG and PET.

• The Plant Pathology Journal
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• v.29 no.1
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• pp.77-86
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• 2013

Anthracnose development by Colletotrichum musae was observed to be significantly less in the fruits of the banana cultivar 'Embul' (Mysore, AAB) infected with Phyllosticta musarum than in fruits without such infections. Anthracnose disease originates from quiescent C. musae infections in the immature fruit. P. musarum incites minute, scattered spots, referred to as freckles, in the superficial tissues of immature banana peel which do not expand during maturation or ripening. P. musarum does not appear to have a direct suppressive effect on C. musae as conidia of C. musae germinate on both freckled and non-freckled fruit forming quiescent infections. Our investigations have shown that P. musarum infection induced several defence responses in fruit including the accumulation of five phytoalexins, upregulation of chitinase and ${\beta}$-1,3-glucanase, phenylalanine ammonia lyase (PAL) activity and cell wall lignification. $^1H$ and $^{13}C$ NMR spectral data of one purified phytoalexin compared closely with 4'-hydroxyanigorufone. Some of the P. musarum-induced defences that retained during ripening, restrict C. musae development at the ripe stage. This paper examines the potential of P. musarum-induced defences, in the control of anthracnose, the most destructive postharvest disease in banana.

• Journal of Microbiology and Biotechnology
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• v.21 no.3
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• pp.293-298
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• 2011

Nitrifying bacterial community structures of suspended and attached biomasses in a full-scale integrated fixed-film activated sludge process were investigated by analyzing 16S rRNA gene sequences obtained from pyrosequencing. The suspended biomass had a higher number of ammonia-oxidizing bacterial sequences (0.8% of total sequences) than the attached biomass (0.07%), although most of the sequences were within the Nitrosomonas oligotropha lineage in both biomasses. Nitrospira-like nitrite-oxidizing bacterial sequences were retrieved in the suspended biomass (0.06%), not in the attached biomass, whereas the existence of Nitrobacter-like sequences was not evident. The suspended biomass had higher nitrification activity (1.13 mg N/TSS/h) than the attached biomass (0.07 mg N/TSS/h). Overall, the results made it possible to conclude the importance of the suspended biomass, rather than the attached biomass, in nitrification in the wastewater treatment process studied.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.3
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• pp.386-391
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• 2017

Objective: Protein supplementation is costly and can result in excess nitrogen (N) excretion. The objective of this study was to evaluate the effects of feeding different levels of dietary protein on average daily gain, body size, rumen fermentation, and nitrogen excretion of 8 to 10 month-old Holstein heifers. Methods: Thirty-six Holstein heifers were divided into 12 blocks according to age ($273{\pm}6.2d$) and were randomly assigned to diets containing a low (10.2% dry matter [DM]), medium (11.9% DM), or high (13.5% DM) level of dietary crude protein (CP). All diets contained approximately 70% roughage and 30% concentrate with similar dietary metabolizable energy (ME) content (2.47 Mcal/kg). Results: Dry matter intake did not differ among the treatments, and average daily gain increased with the increasing dietary protein, 0.79, 0.95, 0.97 kg/d for low, medium, and high group, respectively. Body height increased linearly with increasing dietary CP but no other significant differences in body dimensions were found among the treatments. The increased ratios of dietary CP improved the rate of rear teat length growth remarkably (p<0.05). There was no difference in rumen pH or ruminal major volatile fatty acid (acetate, propionate, and butyrate) concentration among the 3 diets, but rumen ammonia-N concentration increased with the higher dietary CP (p<0.05). Increasing N intake led to increased total N excretion; urinary N excretion was significantly increased (p<0.05) but fecal N excretion was similar among the treatments. Conclusion: These data suggest that the diet containing 11.9% CP (ME 2.47 Mcal/kg) could meet the maintenance and growth requirements of 9 to 11 month-old Holstein heifers gaining approximately 0.9 kg/d.

• Korean Journal of Veterinary Service
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• v.29 no.4
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• pp.459-467
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• 2006

This study was designed to investigate if there were groundwater contamination in 17 landfill where slaughtered animals were buried during the crisis of 2002 foot-and-mouth-disease (FMD) outbreaks in Gyeonggi province. From March to August 2005 groundwater was collected once a month from 17 sites, and examined with potential for hydrogen (pH), colour, turbidity, lead (Pb), arsenic (As), mercury (Hg), cadmium (Cd), copper (Cu), zinc (Zn) , iron (Fe), manganese (Mn) , aluminium (Al), nitrate-nitrogen $(NO_3-N)$, ammonia-nitrogen $(NH_3-N)$, microbial pathogen and Escherichia spp. In the examination of $NH_3-N$ which of the mean concentration was from not-detected (ND) to 0.05 mg/l. The range of $NH_3-N$ level was $0.3-24.1mg/{\ell}$. However, groundwater from four sites was to go beyond the drinking water quality standard (DWQS), i.e., the mean concentration of those were $15.5mg/{\ell}\;(site\;1),\;20.7mg/{\ell}\;(site\;9),\;24.1mg/{\ell}\;(site\;13)\;and\;10.6mg/{\ell}\;(site\;17)$. In the investigation of pH, colour and turbidity, all of the pH were below of DWQS (pH 5.8-6.6), but one site in color test and four sites in turbidity test were over the standard level. Among 9 metal ions examined, Mn was in excess of DWQS, and its concentration was $2.4mg/{\ell}$. Pb, Cd, Hg and As were not traced. The contents of Cu, Zn, Fe and Al were $ND-0.22mg/{\ell},\;0.01-0.05mg/{\ell},\;ND-0.05mg/{\ell}\;and\;0.03-0.16mg/{\ell}$, respectively. Escherichiae spp were not identified, but bacterial colonies were detected at 3 groundwater including 2 sites over the DWQS at the level of $491CFU/m{\ell}\;(site\;4)\;and\;217CFU/m{\ell}\;(site\;15)$.