• International Journal of Industrial Entomology and Biomaterials
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• 제44권2호
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• pp.29-36
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• 2022

Over the past decades, silk sericin (SS) received increasing attention in the academic and industrial fields. In nature, SS acts as a glue that holds the two strands of silk fibrils together. However, recent works suggest that SS might have a more diverse role during the silk spinning process, such as stabilizing the SF in the silk gland. On the other hand, the sericulture industry has been trying to find novel applications for SS discarded from the silk fabric manufacturing process. Recovery and refining of SS would be the first step of the recycling of SS. Using a proper solvent SS could be shaped into various forms, such as spherical beads, microparticles, fibers, and films. Moreover, the applicability of these SS materials has been investigated in various fields such as cosmetics, templates for nanomaterials, drug delivery, heavy metal adsorption, and enzyme immobilization.

• Journal of Microbiology and Biotechnology
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• 제27권4호
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• pp.791-807
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• 2017

The type II secretion system (T2SS), which transports selected periplasmic proteins across the outer membrane, has rarely been studied in nonpathogens or in organisms classified as Betaproteobacteria. Therefore, we studied Cupriavidus metallidurans (Cme), a facultative chemilithoautotroph. Gel analysis of extracellular proteins revealed no remarkable differences between the wild type and the T2SS mutants. However, enzyme assays revealed that native extracellular alkaline phosphatase is a T2SS substrate, because activity was 10-fold greater for the wild type than a T2SS mutant. In Cme engineered to produce three Ralstonia solanacearum (Rso) exoenzymes, at least 95% of their total activities were extracellular, but unexpectedly high percentages of these exoenzymes remained extracellular in T2SS mutants cultured in rich broth. These conditions appear to permit an alternative secretion process, because neither cell lysis nor periplasmic leakage was observed when Cme produced a Pectobacterium carotovorum exoenzyme, and wild-type Cme cultured in minimal medium secreted 98% of Rso polygalacturonase, but 92% of this exoenzyme remained intracellular in T2SS mutants. We concluded that Cme has a functional T2SS despite lacking any abundant native T2SS substrates. The efficient secretion of three foreign exoenzymes by Cme is remarkable, but so too is the indication of an alternative secretion process in rich culture conditions. When not transiting the T2SS, we suggest that Rso exoenzymes are probably selectively packaged into outer membrane vesicles. Phylogenetic analysis of T2SS proteins supports the existence of at least three T2SS subfamilies, and we propose that Cme, as a representative of the Betaproteobacteria, could become a new useful model system for studying T2SS substrate specificity.

• 한국물환경학회지
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• 제27권6호
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• pp.868-876
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• 2011

A five-year field monitoring was conducted to monitor characteristics of suspended solid (SS) export from paddy fields. The observed EMCs of SS ranged 1.2~517 mg/L (avg. 52.1 mg/L) during storm period. The concentration of SS during non-storm period were 1.1~349.5 mg/L (avg. 36.1 mg/L). Monthly load of SS was high during summer when rainfall amount was high. The load was higher than that of May when tillage effect is expected. There was no significant relationship between SS EMCs and rainfall or drainage amount. However, effects of rainfall and drainage were found to be significant for event load of SS. But, there was no apparent relationship between rainfall amount of cropping period and load of SS for that period. The observed SS load was 164.8~456.0 kg/ha (avg. 301.2 kg/ha) and mostly occurred during storm period. This study results also suggested that SS load estimation by USLE equation for paddy field could be overestimated, if not carefully handled. Monitoring studies for various climate, soil, and agricultural management are required to get better scope of SS export from paddy fields.

• 한국토양비료학회지
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• 제18권1호
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• pp.38-49
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• 1985

Sewage sludge를 시용하지 않은 토양(W), 6년간 시용한 토양($WS_6$), Swedge sludge와 토양의 혼합물을 1 주일동안 incubation한 토양( $WS_1$), 그리고 Sewage sludge (SS)로부터 각각 수용성 유기물을 추출, 정제하고 원소분석, 작용기분석을 함과 동시에 IR, UV-VIS, NMR spectroscopy에 의하여 구조적 특성을 조사하였다. SS는 W보다 H, N, P 함량이 많아서 높은 H/C비와 낮은 C/N비로 특징지워 졌으며 total acidity, carboxyl group, phenolic hydroxyl group 함량의 경우 일반적으로 SS가 가장 높았고 그 다음이 $WS_6$, $WS_1$, 그리고 W가 가장 낮았다. Aromatic character나 aromatic carboxyl group 함량은 W가 가장 크고 SS가 가장 적었으며, Aliphatic proton, aliphatic carboxyl group 함량은 SS가 가장 많고 W가 가장 적었다. 단백질 분해산물은 SS에서 풍부했고 W에서는 검출되지 않았다. NMR spectra는 SS의 수소가 W보다 다양한 functional group에 결합되어 있다는 것을 보여 주었으며 aromatic proton의 구조적 주변환경도 SS가 가장 복잡하고 그 다음이 $WS_1$, $WS_6$, 그리고 W가 비교적 단순함을 보여 주었다.

• The Plant Pathology Journal
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• 제25권1호
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• pp.47-53
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• 2009

Sequence analysis of the Chlorella virus SS-2 revealed one putative nuclease gene that is 807 bp long and encodes a 31kDa protein. Multiple sequence alignment analysis reveals the presence of highly conserved PD-(D/E)XK residues in the encoded protein. The gene cloned into an expression vector was expressed as a His-tagged fusion protein in chaperone containing pKJE7 cells. The recombinant protein was purified using a His-Trap chelating HP column and used for functional analysis. Exonuclease activity of the SS-2 nuclease was detected when the DNA substrates, such as linear ssDNA, PCR amplicon, linear dsDNA with 5'-overhang ends, 3'-overhang ends, or blunt ends were used. Covalently closed circular DNA was also degraded by the SS-2 recombinant protein, suggesting that the SS-2 nuclease has an endonuclease activity. Stable activity of SS-2 nuclease was observed between $10^{\circ}C$ and $50^{\circ}C$. The optimum pH concentrations for the SS-2 nuclease were pH 6.0-8.5. Divalent ions inhibited the SS-2 nuclease activity.

• The Korean Journal of Pain
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• 제14권2호
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• pp.136-141
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• 2001

Background: Sodium salicylate (SS) is a nonsteroidal anti-inflammatory drug (NSAID) for the treatment of neuralgia or pain from rheumatoid arthritis. When abused or used in excess, SS can induce cytotoxicity. The present study examined whether SS has a neurotoxic effect. Methods: Cell viability was examined by MTT [3-(4,5-dimethylthiazol-2,5-dipheny ltetrazolium bromide] assay and Sulforhodamine (SRB) assay after cultivating dorsal root ganglion (DRG) neurons derived from neonatal mouse. These cells were treated with various concentrations of SS for 24 hours. In addition, the amount of protein synthesis against SS was measured in these cultures. Results: Cell viability (20, $40{\mu}g/ml$ SS) significantly decreased in a dose-dependent manner. Additionally, SS inhibited protein synthesis after the exposure of cultured mouse DRG neurons to $30{\mu}g/ml$ of SS for 24 hours. Conclusions: The present study suggests that SS is toxic in cultured DRG neurons derived from neonatal mouse by decreasing cell viability and the amount of protein synthesis.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.1028-1031
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• 1997

The SS (Semi-solid) diecasters usually cany out the SS d~ecastmg experiments before producing new products. At the SS diecasting stages, the runner-gate part is always repeatedly corrected, which leads to a lengthened processing time and increased processing cost. The SS diecasting die design should consider component system factors. such as runner, gate, biscuit, overflow and airvent. A large amount of experience is essential in manual assessment and if the design is defective, much time and a great deal of efforts will be wasted in the modification of the d~e. Thus human negligence should be minimized. In this study, die design system for SS diecasting process has been developed to present algonthm of die design, especially runner-gate system. In addition, specific rules and equations for runner-gate system have been presented to avoid too many trials and errors with expensive equipment. It is possible for engineers to be efficient die design of SS diecasting and it will result in reduction of expense and time to be required. And we developed CAD system for SS diecasting die design by AutoLISP language under AutoCAD using proposed algorithm and the database. In addition, we developed the vector analysis program for filling pattern of SS metals.

• 한국유기농업학회지
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• 제24권2호
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• pp.253-262
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• 2016

친환경농자재 11종을 대상으로 황색참다래 과실무름병에 대한 항균활성 검정결과 SS (B. subtilis 10%), WS (Microbial extract 70%), DS (Sulfur 78%) 3종을 선발하였다. SS, WS, DS를 PDA 배지에 10일 동안 처리 시 B. dothidea의 균사 생장 저해 정도는 각각 94.2%, 65.2%, 58.9%였다. 선발 친환경농자재를 이용한 저장시험에서 WS와 SS가 병 방제 효과가 좋았다. 포장시험에서는 SS와 WS 단독 처리, DS-WS와 WS-SS 교호처리가 효과적이었다.

• 한국작물학회지
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• 제46권5호
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• pp.416-419
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• 2001

Hypernodulation soybean mutant, SS2-2, is characterized with greater nodulation and nitrogen fixing ability in the root nodule than its wild type, Shinpaldalkong 2. The present study was performed to identify a genetic locus conferring hypernodulation in soybean mutant SS2-2 and to determine whether the gene controlling the hypernodulation of SS2-2 is allelic to that controlling the supernodulation of nts382 mutant. Hybridization studies between SS2-2 and Taekwangkong revealed that the recessive gene was responsible for the hypernodulation character in soybean mutant SS2-2. Allelism was also tested by crossing supernodulating mutant nts382 and hypernodulating mutant SS2-2 that both hypernodulation and supernodulation genes were likely controlled by an identical locus. Molecular marker mapping of hypernodulation gene in SS2-2 using SSR markers confirmed that the gene conferring hypernodulation was located at the same loci with the gene conferring supernodulation. It is interesting to note that the same gene controlled the super- and hyper-nodulation characters, although SS2-2 and nts 382 exhibited differences in the amount of nodulation in the root system. Further genetic studies should be needed to clarify the genetic regulation of super- and hyper-nodulation in soybean.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2005년도 한국컴퓨터종합학술대회 논문집 Vol.32 No.1 (A)
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• pp.388-390
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• 2005

IEEE 802.16은 BWA (Broadband Wireless Access) 시스템의 표준으로 현재 많은 연구와 함께 상용 제품에 대한 연구가 진행중인 분야이다. IEEE 802.16에서는 QoS를 제공하기 위하여 BS (Base Station)와 SS(Subscriber Station)간의 QoS 협상 과정을 정의하고 있으며, BS 및 SS에서의 효율적인 QoS 보장을 위해 4가지의 서비스 클래스를 정의하고 있다. 이러한 서비스 클래스는 UGS, rtPS, nrtPS, 그리고 BE 이다. 하지만 표준에서는 이러한 서비스 클래스를 어떻게 이용할 것인지에 태한 언급이 없으며, 이에 따라 효율적인 packet scheduling에 관한 않은 연구가 진행되어 왔다. 기존 연구에서는 주로 BS에서의 효율적인 scheduling에 초점을 맞추어 연구가 진행되었으며, SS에서의 scheduling에 대한 연구는 거의 되어 있지 않다. 하지만 BS에서 SS에게 대역폭을 할당할 때 GPSS (Grants per subscriber station) mode로 대역폭을 할당한다면 SS에서는 할당 받은 대역폭을 효율적으로 사용하기 위하여 scheduling이 필요하다. 본 논문에서는 SS에서 효율적인 대역폭 사용을 가능하도록 하기 위한 scheduling 알고리즘을 제안하고자 한다. 제안하는 알고리즘은 SS의 상황에 맞추어서 주어진 대역폭을 보다 더 효과적으로 이용하는데 초점을 맞추고 있다. 성능 명가를 통하여 제안하는 알고리즘이 기존 알고리즘에 비해서 보다 더 효율적으로 대역폭을 사용함을 알 수 있다.