• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.4
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• pp.111-120
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• 2014

The aim of this study is to develop an integrated urea-SCR catalytic filter system for reducing soot and $NO_X$ emissions simultaneously in diesel engines. In this study, the characteristics of exhaust emissions relative to reactive activation temperature under four kinds of engine loads are experimentally investigated by using a four-cycle, four-cylinder, direct injection type, water-cooled turbo intercooler ECU common-rail diesel engine with the integrated urea-SCR $MnO_2-V_2O_5-WO_3/TiO_2/SiC$ catalytic filter system operating at three kinds of engine speeds. The urea-SCR reactor is used to reduce $NO_X$ emissions, and the catalytic filter system is used to reduce soot emissions. The reactive activation temperature is very important for reacting a reducing agent with exhaust emissions. The reactive activation temperatures in this experiment is applied to 523, 573 and 623 K. The fuel is sprayed by the pilot and main injections at the variable injection timing between BTDC $15^{\circ}$ and ATDC $1^{\circ}$ according to experimental conditions. It is found that the $NO_X$ conversion rate is the highest as 83.9% at the reactive activation temperature of 523 K in all experimental conditions of engine speed and load, and the soot emissions shown by the average reduction rate of approximately 93.3% are almost decreased below 0.6% in all experimental conditions regardless of reactive activation temperatures. Also, the THC and CO emissions by oxidation reaction of Mn, V and Ti are shown in the average reduction rates of 70.3% and 38% regardless of all experimental conditions.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.16 no.3
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• pp.148-154
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• 2016

A urea cycle disorder is a condition caused by a defect of the enzymes in the urea cycle, and deficiency of ornithine transcarbamylase (OTC), which converts carbamoyl phosphate and ornithine into citrulline, is the most common type of the disorder. OTC deficiency induces the accumulation of precursors of urea, ammonia, and glutamine, leading to neurological symptoms including hypotonia, respiratory failure, seizure, lethargy, and coma and sometimes to death. Because OTC deficiency is inherited in an X-linked manner, typical symptoms such as vomiting, poor feeding, and lethargy appear mainly in male neonates. We recently had a case that presented with neonatal onset lethargy, vomiting, and apnea in a 4-day-old boy. He was diagnosed with OTC deficiency by biochemical phenotype, including hyperammonemia and an increased orotic acid level in the urine. Genetic analysis of the OTC gene showed a novel mutation c.780_781insCAGGCAGTGT (p.Ile261Glnfs*35). He was treated for hyperammonemia using continuous venovenous hemofiltration (CVVH) at 118 hours after birth. After 4 days of CVVH, his consciousness and blood ammonia concentration were normalized, and he was discharged at the age of 53 days. At around 12 months of age, bilateral femur fractures and osteomyelitis occurred in this patient. Two months after the fracture, he died of septic shock, insulin-resistant hyperglycemia, and multi-organ failure.

• Reproductive and Developmental Biology
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• v.34 no.3
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• pp.201-205
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• 2010

The objective of this study was investigate the superovulation treatment and to relate concentrations of blood urea nitrogen(BUN) in Hanwoo donors. Thirty six, at random stages of the estrous cycle, received a CIDR. Four days later, the animals were superovulated with a total of 28AU FSH (Antorin, 2AU=1 ml) administered twice daily in constant doses over 4 days. On the 3th administration of FSH, CIDR was withdrawn and 25 mg $PGF_2a$ was administered. Cows were artificially inseminated twice after estrous detection at 12 hr intervals. The cows received $100\;{\mu}g$ GnRH at the time of 1st insemination. Embryos were recovered 7 or 8 days after the 1st insemination. Cows with BUN <10, 11~18 and ${\geq}$19 mg/dl had return of estrus of 34.6, 30.5 and 30.4 days respectively. Return of estrus after superovulation treatment was not significantly lower for cows with blood urea nitrogen (BUN) above 10 mg/dl than for cows with BUN below 10 mg/dl. Cows with BUN <10, 11~18 and ${\geq}$19 mg/dl had number of transferable embryos of $3.2{\pm}1.2$, $5.4{\pm}1.9$ and $4.1{\pm}2.1$ respectively.

• The Korean Journal of Zoology
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• v.31 no.4
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• pp.251-264
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• 1988

동면 상태에서 혈액성분의 생화학적 변화치를 조사하고자 전남 각지에 서식 또는 광주직할시 근교에서 양식하고 있는 뱀장어, 개구리, 살모사 그리고 다람쥐를 활동기(7월∼8월), 잠입기(10월∼11월), 동진기(12월∼1월) 및 각려기(3월∼4월)에 채집하였다. 이들 동물들의 혈청에서 Total protein, Albumin, Globulin, A/G ratio, Glucose, Calcium, Urea함유량을 조사하여 얻은 성적을 비교 검토하여 다음과 같은 결론을 얻었다. 1 . Total protein의 변화는 각 동물사이에서 상당한 차이를 보이되 잠입기에 다소 증가하였다. 특히 다람쥐에서 Total protein 함유량이 다른 동물들 보다 많았다. Albumin함유량은 잠입기에 상승하였고 동면기에는 약간의 감소를 보이다가 각성기에는 현저한 감소를 보였다. gloulin함유량은 잠입기에 상당히 상승하고 동면기에 약간의 감소를 나타내었으며 각성기 인 봄철에는 많은 증가 현상을 보였다. 2. 혈청 Urea의 함유량은 동면의 각과정에 따라 상당한 차이가 있었다. 즉 잠입기에 약간 상승하고 동면기에는 저하를 보였으며 각성기에는 전 실험동물에서 검출되지 않았다. 3. 혈당의 변화는 잠입기에 대체로 저하하고 동면기에는 심한 저혈당 수준에 이르렀다. 각성기인 봄철에는 다람쥐를 제외하고는 동면기의 혈희량과 유사하였다. 4. 혈청 Calcium함유량의 변화는 활동기에 비하여 잠입기에는 상당한 증가현상을 보였으나동면기에는 전 실험동물이 거의 같은 수준으로 감소를 보이며 각성기에 까지 감소하였다. In order to the biochemical change of the serological components of hibernating animals, eels(hnguillo joponica Temminck et Schlegel), frogs (Rana nigromacurata Hallowell), snakes (Agkistro-don holds breuicaudus Stejneserl, squirrels (Tamias striatus Linnaeus) which were collected around Gwangiu city and the Chunnam area were observed in accordance with the phases of hibernation. The author described the hibernating cycle as active (June-July), prehibematins(October-Novemberl, hibernating (December-January) and posthibemating phase (March-Aprill. The values of total protein, albumin, globulin, hJG ratlo, calcium, glucose and urea were chiefly investigated in their serum. The results are as following: Total protein was shown to be consider-able in eels, frogs, snakes, squirrels and increased in prehibemation. Especially, the mean value was high in sqirrels. Albumin values was increased during prehibemation. But a little decrease was shown during hibernating and an outstanding decrease during posthibemation. The globulin value increased considerably during prehlbemation but decreased a little during hibernation phase. Changes of urea were shown to be considerable according to the stage of each hibem3-tion. A little increase was shown during prehibemation and decrease during hibernating stage. but urea was not found in posthibemation in any experimental animals. The glucose value was generally decreased during prehibematlon. An extremely little increase in glucose was shown during hibernation (hypoglycemia). All hibernating values except those for squirrels in spring posthibemating phase were at almost the same level. The calcium value was shown to be considerable during prehibemation in comparison with active phase. The same level of decrease was represented in all kinds of animals and continued at the stage of posthibemation.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.16 no.2
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• pp.62-69
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• 2016

Newborn screening of some urea cycle disorders has little benefits because of early severe symptoms before the result, low sensitivity (especially hypocitrullinemia) and poor prognosis. But in case of citrullinemia, citrin deficiency and argininosuccinic aciduria diagnosed as elevated citrulline, newborn screening is helpful for early diagnosis and treatment before the symptom. Distinction between the clinical forms of these diseases is based on clinical findings and biochemical results, however, they may not be clearcut. Treatment is different from each other, so exact diagnosis is essential. Here, the diagnostic algorithm for elevated citrulline after tandem mass screening has been proposed. Minimizing total process time from sampling to report of the results is important in Korea for diagnosis and treatment of these disorders.

• Journal of Plant Biotechnology
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• v.36 no.4
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• pp.397-402
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• 2009

Ornithinine carbamoyltransferase (OTC) is an enzyme that catalyzes the key step in arginine biosynthesis in bacteria and plants. OTC is also involved in the urea cycle and deficiency of the enzyme in human leads to disease. The argF gene encoding OTC has been reported in many bacteria and few plants. Here we report the characterization of a gene encoding OTC from rice (OsOTC). Analysis of a cDNA sequence from rice revealed that the full-length open reading frame of OsOTC consisted of 367 amino acids, corresponding to a protein of approximately 39.7 kDa. The predicted amino acid sequence of OsOTC harbor distinct five OTC signature sites and is highly homologous to that of enzymes of plants, animals and many bacterial OTCs. Expression of OsOTC in argF mutants of Escherichia coli showed that the gene was able to functionally complement to the mutant. These results suggest that the OsOTC encode a protein for ornithine carbamoyltransferase in rice.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.820-826
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• 2008

Differ number of seismograph to the composition dam by recently frequent earthquake and analyzed responsiveness. Interest for dam inner place by increase of something wrong flood and inside and outside of the country earthquake appearance according to unusual change of weather is risen, on important urea in dam safety floodgate school register by structural safety divide can. Therefore, by PMP (PMF) of dam and increase of domestic earthquake occurrence, need research about earthquake resistant nature ability estimation of water resources facilities. Because responsiveness analysis applies number 0.154 ~ 0.25 g of seismograph, seismic wave that use in analysis is being suitable in dynamic analysis of construction such as Rockfill dam from representative chapter cycle faction and recommend in domestic internal examination design workbook, and use results applied much Hachinohe wave onions in van abroad.

• Clinical and Experimental Pediatrics
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• v.62 no.2
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• pp.43-47
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• 2019

Hyperammonemia can be caused by several genetic inborn errors of metabolism including urea cycle defects, organic acidemias, fatty acid oxidation defects, and certain disorders of amino acid metabolism. High levels of ammonia are extremely neurotoxic, leading to astrocyte swelling, brain edema, coma, severe disability, and even death. Thus, emergency treatment for hyperammonemia must be initiated before a precise diagnosis is established. In neonates with hyperammonemia caused by an inborn error of metabolism, a few studies have suggested that peritoneal dialysis, intermittent hemodialysis, and continuous renal replacement therapy (RRT) are effective modalities for decreasing the plasma level of ammonia. In this review, we discuss the current literature related to the use of RRT for treating neonates with hyperammonemia caused by an inborn error of metabolism, including optimal prescriptions, prognosis, and outcomes. We also review the literature on new technologies and instrumentation for RRT in neonates.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.6
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• pp.774-780
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• 2011

Inadequate supply of glucose or glucogenic substrates to the body tissues can affect metabolism of absorbed acetogenic metabolites from the gut and therefore, influence feed intake in ruminants. This study investigated the effect of energy supplementation on rumen kinetics in the gut, and the acetate clearance rate in the body tissues of sheep fed low quality basal roughage. A basal diet consisting of urea-treated mixture of wheaten chaff and barley straw (3:1 DM) containing 22.2 g N/kg DM was used. Four Merino cross wethers weighing $45{\pm}4.38\;kg$ fitted with permanent rumen and abomasal cannulae were allocated to four treatments in a $4{\times}4$ LSD. The treatments were basal diet ($E_0$), or basal diet supplemented with sucrose (112.5 g/d) administered intraruminally ($E_R$), abomasally ($E_A$), or via both routes (50:50) ($E_{RA}$). There was no difference (p>0.05) in the rumen liquid kinetics parameters between the four dietary treatments. However, there was a trend of animals supplemented with sucrose wholly or partly through the abomasum having lower faecal DM and therefore poor pellet formation, and low pH. Although the glucogenic potential of the fermentation products absorbed from the rumen was increased (p<0.001) by intra-ruminal supplementation with sucrose ($E_R$ and $E_{RA}$), there was no significant difference (p<0.05) in acetate clearance rate between the four dietary treatments.

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.1
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• pp.21-30
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• 2006

[ $M/Fe_2O_3$ ] (M=Rh, Ce and Zr) mixed oxides were prepared using urea method to develop a medium for chemical hydrogen storage by their redox cycles. And their redox behaviors by repeated cycles were studied using temperature programmed reaction(TPR) technique. Additives such as Rh, Ce and Zr were added to iron oxides in order to lower the reaction temperature for reduction by hydrogen and re-oxidation by water-splitting. From the results, concentration of urea used as a precipitant had little effect on particle size and reduction property of iron oxide. TPR patterns of iron oxide consisted of two reduction peaks due to the course of $Fe_2O_3\;{\rightarrow}\;Fe_3O_4\;{\rightarrow}\;Fe$. The results of repeated redox tests showed that Rh added to iron oxide have an effect on lowering the re-oxidation temperature by water-splitting. Meanwhile, Ce and Zr additives played an important role in prevention of deactivation by repeated cycles. Finally, Fe-oxide(Rh, Ce, Zr) sample added with Rh, Ce and Zr showed the lowest re-oxidation temperature by water-splitting and maintained high $H_2$ recovery in spite of the repeated redox cycles. Consequently, it is expected that Fe-oxide(Rh, Ce, Zr) sample can be a feasible medium for chemical hydrogen storage using redox cycle of iron oxide.