• 한국초지조사료학회지
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• 제9권2호
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• pp.82-87
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• 1989

A field experiment was carried out to determine the effects of 11 different application levels of nitrogen (N), phosphorous ($P_2O_5$) and potassium($K_2O$) fertilizer in late-autumn on the winter survival, early spring growth and dry matter(DM) yield, carbohydrate reserves (CHO-R) in stubble of grasses, and botanical composition in orchardgrass dominated existing pasture in Suwon from October, 1987 to May, 1988. Winter survival of grasses was high (ca. 90%) in all N-fertilized plots, regardless of $P_2O_5$ and $K_2O$ application, and those in zero-N and zero-NPK plots were low as 86.5% and 81.4%, respectively. Early spring growth was vigorous in N-fertilized plots. Heading rate at the fist harvest was 80-86% in all N plots, regardless of $P_2O_5$ and $K_2O$, while those in zero-N and zero-NPK plots were very low as 61% and 56%, respectively. The DM yield of first harvest was higher in the plots of N 35 kg(Site B) and N 70kg $ha^{-1}$ (Site A), regardless of $P_2O_5$ and $K_2O$ level, and those in zero-N and zero-NPK plots were very low (p < 0.05). But no significant difference of yield was observed between N 75 kg and N 105 kg. CHO-R in stubble and legumes were high in zero-N and zero-NPK plots, and low relationship was found between winter survival and CHO-R of grasses. Winter survival, early spring growth and DM yield were significantly influenced by N fertilizer. In this experiment, the optimum application level of N in late-autumn could be recommended in 35-70 kg $ha^{-1}$, and no beneficial effects were observed by $P_2O_5$ and $K_2O$ fertilizer.

• 정보화연구
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• 제11권3호
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• pp.285-310
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• 2014

인터넷을 기반으로 한 서비스가 확대되면서 전통적인 인재교류시장 환경에 대한 대안으로 인터넷을 통해 구직자의 취직 환경을 촉진 지원하며, 구직자가 자기 주도적으로 취직하도록 도와주는 취업정보 사이트가 빠르게 확산되고 있다. 이에 취업정보 사이트의 품질에 대하여 영향을 미치는 직간접적인 요인들도 증가하고 있다. 한국과 마찬가지 중국에서도 취업정보 사이트 품질에 영향을 미치는 요인의 중요성을 인식하고 있다. 그러나 아직 중국 구직자가 취업정보 사이트를 효과적으로 활용하는 비율이 한국보다는 낮고 취업정보 사이트의 영향요인에 관한 한국과 중국 간 비교 연구가 충분히 이루어지지 않았다. 본 연구에서는 한국과 중국의 서로 다른 온라인 취업 환경에서 구직자에게 영향을 줄 것이라고 생각하고 먼저 취업정보 사이트를 이용한 경험이 있는 한국과 중국 대학생 및 대학원생을 대상으로 양국 간의 취업정보 사이트의 품질요인에 대한 인식도 차이를 알아보고 국가별 특성에 적합한 웹 서비스를 제공할 때 효율적으로 활용이 가능한 유용한 시사점을 도출하였다.

• Archives of Plastic Surgery
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• 제34권3호
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• pp.330-335
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• 2007

Purpose: The purpose of this study is to evaluate the functional outcome and donor site morbidity of anterolateral thigh free flap(ALT) compared to Radial forearm free flap(RFFF) for the reconstruction of partial glossectomy defect. Methods: 5 ALT free flap (group I) were attempted for partial glossectomy patients. We compared patients undergone ALT flap with those(n=11) of similar size defect reconstructed with RFFF (Group II). Rating scales for articulation and swallowing function were applied and donor site morbidity have been evaluated. Results: The scales for speech function showed no difference between the two groups (average score; group I - 6.4, group II - 6.45). Swallowing function also showed no difference between the two groups(average score; Group I - 6.6, Group II - 6.27). ALT group had one patient with donor site morbidity(numbness). All of the RFFF patients(11/11) complained and suffered from hypertrophic scar, retraction, numbness or hyperpigmentation on forearm donor site. Based on our study, ALT free flap is comparable to that of RFFF in terms of functional assessment in tongue reconstruction. Conclusion: Considering the donor site morbidity, ALT flap is to be valuable to reconstruct partial glossectomy defect.

• 한국산림과학회지
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• 제101권1호
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• pp.53-61
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• 2012

이 연구는 기후변화를 고려한 낙엽송의 생장모형을 추정한 후 이에 따른 영향을 분석하는 데 있다. 이를 위해 종속변수는 지위지수, 독립변수는 입지, 기상, 토양인자를 설정하였으며, WLS 모형을 이용하여 잣나무의 생장모형을 추정하였다. 이를 토대로 한반도에 적용된 IPCC의 A1B 기후변화 시나리오 따라 $-3.3^{\circ}C$에서 $+3.3^{\circ}C$까지 시뮬레이션한 결과, $-0.8^{\circ}C$를 정점으로 지위지수는 감소하는 것으로 분석되었다. 이러한 결과를 바탕으로 각 시나리오에 따른 지역별 낙엽송 지위지수의 변화를 분석한 결과, 각 시나리오별 낙엽송의 지위지수는 전반적으로 감소하였으나 일부지역에서는 낙엽송의 지위지수가 증가하는 것으로 나타났다. 하지만 기온이 $3^{\circ}C$ 상승했을 때, 지위지수가 증가한 지역 또한 상대적으로 감소하는 것으로 분석되었다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권6호
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• pp.38-47
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• 2013

This study was performed to identify the optimal operating conditions and to evaluate the xylene removal efficiency, applying in-situ soil flushing with the low concentrated solution of 'Tween 80' at the xylene contaminated site. The pilot scale test site ($5m{\times}5m{\times}3m$), was mainly composed of 'sandy loam', with the average hydraulic conductivity of $9.1{\times}10^{-4}cm\;s^{-1}$. The average xylene concentration of the site was 42.1 mg $kg^{-1}$, which was more than 2.5 times higher than Korea soil pollution warning limit (15 mg $kg^{-1}$). For the soil flushing, 7,800 L of 0.1~0.2% surfactant solution was injected into three injection wells at the average injection time of 9 hr $d^{-1}$ for 10 days, followed by the additional only groundwater injection of 6,000 L. The same amount of the effluent solution was extracted from three extraction wells. From the analysis for xylene concentration of all effluent at 3 extraction wells, total 166 g of xylene was removed by in-situ surfactant flushing. Even though the residual xylene concentrations of 7 soil sampling locations in the test site were different due to the soil heterogeneity, from the comparison of xylene concentration at 7 locations before/after the feasibility test, 53.9% of the initial xylene in the site was removed from three extraction wells (mainly Ext-N and Ext-M well). The results showed that the in-situ soil flushing by using low concentrated 'Tween 80' solution had a great potential to remediate the xylene contaminated site.

• Asian-Australasian Journal of Animal Sciences
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• 제18권9호
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• pp.1226-1230
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• 2005

The present investigation was undertaken to study the genetic polymorphism of the DRB3 exon 2 in 75 crossbred cattle by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Five genotypes i.e. HaeIII-a, HaeIII-b, HaeIII-e, HaeIII-ab and HaeIII-ae were observed when the 284 bp PCR products were digested with HaeIII restriction enzyme. The corresponding frequencies of these patterns were 0.53, 0.04, 0.01, 0.38 and 0.04, respectively. Digestion with RsaI restriction enzyme resolved 24 different restriction patterns. The frequencies of these patterns ranged from 0.013 (RsaI-f, RsaI-k and RsaI-c/n) to 0.120 (RsaI-n). The results revealed that the crossbred cows belonged to the RsaI patterns namely b, k, l, a/l, d/s, l/n, l/o and m/n, whose corresponding frequencies were 0.027, 0.013, 0.040, 0.027, 0.040, 0.067, 0.027 and 0.067, respectively. Digestion of the 284 bp PCR product of DRB3.2 gene with PstI in the crossbred cattle did not reveal any restriction site. These results suggested the absence of the recognition site in some of the animals. These results also revealed that the crossbred cows studied were in homozygous as well as heterozygous condition. On the basis of the above results it can be concluded that the DRB3.2 gene was found to be highly polymorphic in the crossbred cattle population.

• Journal of Microbiology and Biotechnology
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• 제24권12호
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• pp.1636-1643
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• 2014

3-Hydroxybutyryl-CoA dehydrogenase is an enzyme that catalyzes the second step in the biosynthesis of n-butanol from acetyl-CoA, in which acetoacetyl-CoA is reduced to 3-hydroxybutyryl-CoA. To understand the molecular mechanisms of n-butanol biosynthesis, we determined the crystal structure of 3-hydroxybutyryl-CoA dehydrogenase from Clostridium butyricum (CbHBD). The monomer structure of CbHBD exhibits a two-domain topology, with N- and C-terminal domains, and the dimerization of the enzyme was mostly constituted at the C-terminal domain. The mode of cofactor binding to CbHBD was elucidated by determining the crystal structure of the enzyme in complex with $NAD^+$. We also determined the enzyme's structure in complex with its acetoacetyl-CoA substrate, revealing that the adenosine diphosphate moiety was not highly stabilized compared with the remainder of the acetoacetyl-CoA molecule. Using this structural information, we performed a series of site-directed mutagenesis experiments on the enzyme, such as changing residues located near the substrate-binding site, and finally developed a highly efficient CbHBD K50A/K54A/L232Y triple mutant enzyme that exhibited approximately 5-fold higher enzyme activity than did the wild type. The increased enzyme activity of the mutant was confirmed by enzyme kinetic measurements. The highly efficient mutant enzyme should be useful for increasing the production rate of n-butanol.

• ALGAE
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• 제27권3호
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• pp.215-224
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• 2012

Growth dynamics of the seagrass, Zostera marina were examined at the two stations (Myungju and Dagu) in Jindong Bay on the southern coast of Korea. Eelgrass leaf productivities, underwater irradiance, water temperature, dissolved inorganic nitrogen (DIN) in water column and sediments, and tissue carbon (C) and nitrogen (N) content were monitored monthly from March 2002 to January 2004. Underwater irradiance fluctuated highly without a clear seasonal trend, whereas water temperature showed a distinct seasonal trend at both study stations. Water column DIN concentrations were usually less than $5{\mu}M$ at both study sites. Sediment pore water $NH_4{^+}$ and $NO_3{^-}+NO_2{^-}$ concentrations were higher at the Myungju site than at the Dagu site. Eelgrass leaf productivity at both study sites exhibited a distinct seasonality, increasing during spring and decreasing during summer. Seasonal variation of eelgrass productivity was not consistent with seasonal patterns of underwater irradiance, or water temperature. Eelgrass tissue C and N content at both study sites also showed significant seasonal variations. Relationships between tissue C and N content and leaf productivities exhibited usually negative correlations at both study sites. These negative correlations implied that the growth of Z. marina at the study sites was probably limited by C and N supplies during the high growth periods.

• 대한수의학회지
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• 제39권4호
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• pp.772-777
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• 1999

The uncaped genomic RNA of bovine viral diarrhea virus (BVDV) initiates translation by recruitment of eukaryotic translation initiation factors at the internal ribosome entry site (IRES). N-terminal protease ($N^{pro}$) is the first translation product of the open reading frame (ORF). By using the vaccinia virus SP6 RNA polymerase transient expression system, we showed previously that deletion of $N^{pro}$ region reduced translation by 21%. To better understand the biological significance of $N^{pro}$ for translation, we carried out a mutational analysis of the $N^{pro}$ region of BVDV cloned in the intercistronic region of a bicistronic reporter plasmid. We constructed a bicistronic expression vector in which the entire 5 UTR and the mutated $N^{pro}$ region (${\Delta}386-901$, ${\Delta}415-901$ and ${\Delta}657-901$) was cloned between two reporter genes, chloramphenicol acetyltransferase (CAT) and luciferase (LUC). In vivo translation analyses showed that $N^{pro}$ region was dispensible for efficient translation. The results indicate that the $N^{pro}$ region is not essential for BVDV RNA translation and the 3' boundary of BVDV IRES is expanded into $N^{pro}$ region, suggesting that $N^{pro}$ may not play a major role in BVDV replication.

• Journal of Microbiology and Biotechnology
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• 제7권6호
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• pp.373-377
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• 1997

The gene for isopenicillin N synthase (cyclase; IPNS) was cloned from Lysobacter lactamgenus using DNA probe amplified with primers based on the consensus sequences of isopenicillin N synthase genes of other ${\beta}$-lactam-producing microorganisms. The genomic library of L. lactamgenus using pUC18 plasmid cloned at the SacI site were screened with the PCR-generated DNA probe and three positive clones were isolated. Enzyme activities in E. coli clones were confirmed by bioassay and HPLC assay. Throughout the functional mapping, it was observed that the gene for isopenicillin N synthase is located at the 1.3-kb XhoI-BamHI fragment of insert of positive clones. Nucleotide sequencing at both ends of the XhoI-BamHI fragment revealed that IPNS of L. lactamgenus has the common amino acid sequences at amino- and carboxy-termini.