• 한국재료학회지
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• 제16권12호
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• pp.754-760
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• 2006

Mercaptoundecanoic acid (MUA) has been used to enhance the dispersity of Au nanoparticles in organic solvent and the affinity between the Au nanoparticles surface and titanium dioxide shell in the synthesis of $Au/TiO_2$ core-shell composite nanoparticles. The dispersity of the MUA-coated Au nanoparticles in ethanol aqueous solution with different concentration of $H_2O$ was investigated by UV-Vis. absorption spectrum and the coating amount of MUA was varied from 0.02 mM to 1.0 mM. The MUA-coated Au nanoparticles were highly dispersed in pure $H_2O$ in the wide range of the coating amount of MUA. On the contrary, the MUAcoated Au nanoparticles showed an enhanced stability in the ethanol/$H_2O$=8/2 mixed solution only when the coating amount of MUA was 0.05 mM, and in the ethanol/$H_2O$=7/3 mixed solution when the coating amount of MUA was in the range from 0.02 mM to 0.17 mM. From this systematic study, it can be inferred that the stability and the dispersibility of Au nanoparticles in organic solvents are highly sensitive towards the amount of MUA coating.

• Bulletin of the Korean Chemical Society
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• 제30권11호
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• pp.2651-2654
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• 2009

In borohydride-protected nanosilvers in laponite sol, the silver particles aggregate to form short chains and a dumbbell shape. The $^{1}H$ NMR measurements in this study represent, to our knowledge, the first observation of proton resonances of borohydride-protected nanosilvers in aqueous solution. Borohydride on nanosilver can be exchanged with 11-mercaptoundecanoic acid (MUA) or trioctylphosphine (TOP). Transmission electron microscopy and UV-Vis spectroscopy data show that the number of aggregated silver nanoparticles decreases upon addition of aforementioned ligands due to the formation of silver MPCs (monolayer-protected clusters). Adsorption of MUA or TOP on nanosilver is confirmed through the observation of broad proton resonances of MPCs in $^{1}H$ NMR spectra.

• Restorative Dentistry and Endodontics
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• 제42권2호
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• pp.95-104
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• 2017

Objectives: This study evaluated the influence of a multi-mode universal adhesive (MUA) containing silane (Single Bond Universal, 3M EPSE) on the bonding of resin cement to lithium disilicate. Materials and Methods: Thirty IPS e.max CAD specimens (Ivoclar Vivadent) were fabricated. The surfaces were treated as follows: Group A, adhesive that did not contain silane (ANS, Porcelain Bonding Resin, Bisco); Group B, silane (S) and ANS; Group C, hydrofluoric acid (HF), S, and ANS; Group D, MUA; Group E, HF and MUA. Dual-cure resin cement (NX3, Kerr) was applied and composite resin cylinders of 0.8 mm in diameter were placed on it before light polymerization. Bonded specimens were stored in water for 24 hours or underwent a 10,000 thermocycling process prior to microshear bond strength testing. The data were analyzed using multivariate analysis of variance (p < 0.05). Results: Bond strength varied significantly among the groups (p < 0.05), except for Groups A and D. Group C showed the highest initial bond strength ($27.1{\pm}6.9MPa$), followed by Group E, Group B, Group D, and Group A. Thermocycling significantly reduced bond strength in Groups B, C, and E (p < 0.05). Bond strength in Group C was the highest regardless of the storage conditions (p < 0.05). Conclusions: Surface treatment of lithium disilicate using HF and silane increased the bond strength of resin cement. However, after thermocycling, the silane in MUA did not help achieve durable bond strength between lithium disilicate and resin cement, even when HF was applied.

• Clinics in Shoulder and Elbow
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• 제23권4호
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• pp.169-177
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• 2020

Background: We evaluated the need for arthroscopic capsular release (ACR) in refractory primary frozen shoulder (FS) by comparing clinical outcomes of patients treated with ACR and manipulation under anesthesia (MUA). Methods: We assessed patients with refractory primary FS, 57 patients (group A) who were treated with MUA and 22 patients (group B) who were treated with ACR. In group A, manipulation including a backside arm-curl maneuver was performed under interscalene brachial block. In group B, manipulation was performed only to release the inferior capsule before arthroscopic circumferential capsular release, which was carried out for the unreleased capsule after manipulation. Pain, range of shoulder motion, and American Shoulder and Elbow Surgeons score were recorded at 1 week, 3 months, 6 months, and 1 year after surgery. We compared outcome variables between treatment groups and between diabetics and non-diabetics and also evaluated the numbers of patients receiving additional intra-articular steroid injection. Results: Outcome variables at 3 months after surgery and improvements in outcome variables did not differ between groups. Group A showed significantly better results than group B in the evaluation of pain and range of motion at 1 week. Diabetics showed comparable outcomes to non-diabetics for most variables. Eleven patients required additional steroid injections between 8 to 16 weeks after surgery: 12.2% in group A, 18.2% in group B. Additional injections were given three times more often in diabetics compared to non-diabetics. Conclusions: MUA alone can yield similar clinical outcomes to ACR in refractory FS.

• Applied Biological Chemistry
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• 제32권2호
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• pp.109-115
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• 1989

퇴비(堆肥) 및 비료(肥料) 시비방법별(施肥方法別)로 무비구외(無肥區外) 7처리(處理)로 21년간(年間) 시험한 미사식양질계(微砂埴壤質系) 보통답(普通畓)에서 urease, L-glutaminase, phosphatase 활성(活性)을 조사하였다. 총(總) urease 활성(活性)(TUA)과 미생물(微生物) 분필(分泌) urease 활성(活性)(MUA)은 처리간(處理間)에 차이가 심하였으나, 토양(土壤)에 축적(蓄積)된 urease 활성(活性)(AUA)은 처리간(處理間)에 차이가 경미(輕微)하였다. 특히 MUA는 3요소(要素)와 퇴비(堆肥), 3요소(要素)와 규산(硅酸) 시용구(施用區)에서 가장 높았으며 토양중(土壤中) 인산(燐酸), 가리(加里), 규산(硅酸) 함량(含量)과도 고도(高度)의 유의(有意)한 상관관계(相關關係)가 있었다. 총(總) L-glutaminase 활성(活性)(TGA)과 토양(土壤)에 축적(蓄積)된 L-glutaminase 활성(活性)(AGA)은 처리 간에 차이가 심하였으나, 미생물(微生物) 분필(分泌) L-glutaminase 활성(活性)(MGA)은 처리간에 차이가 경미(輕微)하였으며 활성정도(活性程度)는 AGA와 비슷하였다. 또한 AGA는 토양 중 규산(硅酸), 인산(燐酸) 함량(含量)과 pH와는 고도(高度)의 유의(有意)한 상관(相關)이 있었다. 토양 중 phosphatase 활성(活性)은 toluene 처리와 무처리간에 차이가 경미하였으나, 퇴비(堆肥)와 비료(肥料) 시비방법(施肥方法)에 따른 차이는 심하여서 3요소구(要素區), 3요소(要素)+퇴비구(堆肥區), 3요소(要素)+규산구(硅酸區)에서 활성(活性)이 높게 나타났다. 그리고 phosphatase 활성(活性)과 토양 PH, 규산(硅酸), 인산(燐酸), 칼슘 함량(含量)과는 유의성(有意性)이 있었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권2호
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• pp.112-116
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• 2003

An immunosensor based on surface plasmon resonance (SPR) onto a protein G layer by Self-assembly technique was developed for detection of Legionella pneumophila. The protein G layer by self-assembly technique was fabricated on a gold (Au) surface by adsorbing the 11-mercaptoundecanoic acid (MUA) and an activation process for the chemical binding of the free amino (-NH$_2$) of protein G and 11-(MUA) using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDAC) in series. The formation of the protein G layer by self-assembly technique on the Au Substrate and the binding of the antibody and antigen in series were confirmed by SPR spectroscopy. The Surface topographies of the fabricated thin films on an Au substrate were also analyzed by using an atomic force microscope (AFM). Consequently, an immunosensor for the detection of L. pneumophila using SPR was developed with a detection limit of up to 10$^2$CFU per mL.

• Journal of Microbiology and Biotechnology
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• 제16권8호
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• pp.1169-1173
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• 2006

Imaging ellipsometry (IE) for detection of binding of Escherichia coli O157:H7 (E. coli O157:H7) to an immunosensor is reported. A protein G layer, chemically bound to a self-assembled layer of 11-mercaptoundecanoic acid (11-MUA), was adopted for immobilization of monoclonal antibody against E. coli O157:H7 (Mab). The immobilization of antibody was investigated using surface plasmon resonance. To fabricate antibody spots on a gold surface, protein G solution was spotted onto the gold surface modified with an 11-MUA layer, followed by immobilizing Mab on the protein G spot. Ellipsometric images of the protein G spot, the Mab spot, and Mab spots with binding of E. coli O157:H7 in various concentrations were acquired using the IE system. The change of mean optical intensity of the Mab spots in the ellipsometric images indicated that the lowest detection limit was $10^3$CFU/ml for E. coli O157:H7. Thus, IE can be applied to an immunosensor for detection of E. coli O157:H7 as a detection method with the advantages of allowing label-free detection, high sensitivity, and operational simplicity.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권4호
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• pp.227-232
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• 2003

A self-assembled monolayer of protein G was fabricated to develop an immunosensor based on surface plasmon resonance (SPR), thereby improving the performance of the antibodybased biosensor through immobilizing the antibody molecules (lgG). As such, 11-mercaptoundecanoic acid (11-MUA) was adsorbed on a gold (Au) support, while the non-reactive hydrophilic surface was changed through substituting the carboxylic acid group (-COOH) in the 11-MUA molecule using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrocholide (EDAC). The formation of the self-assembled protein G layer on the Au substrate and binding of the antibody and antigen were investigated using SPR spectroscopy, while the surface topographies of the fabricated thin films were analyzed using atomic force microscopy (AFM). A fabricated monoclonal antibody (Mab) layer was applied for detecting E. coli O157:H7. As a result, a linear relationship was achieved between the pathogen concentration and the SPR angle shift, plus the detection limit was enhanced up to 10$^2$ CFU/mL.

• Journal of Microbiology and Biotechnology
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• 제12권5호
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• pp.780-786
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• 2002

An immunosensor based on surface plasmon resonance (SPR) with a self-assembled protein G layer was developed for the detection of Escherichia coli O157:H7. A self-assembled protein C layer on a gold (Au) surface was fabricated by adsorbing the mixture of 11-mercaptoundecanoic acid (MUA) and hexanethiol at various molar ratios and by activating chemical binding between free amine (-$NH_2$) of protein G and 11-(MUA) using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDAC) in series. The formation of a self-assembled protein G layer on an Au substrate and the binding of the antibody and antigen in series were confirmed by SPR spectroscopy. The surface morphology analyses of the self-assembled protein G layer on the Au substrate, monoclonal antibody (Mab) against E. coli O157:H7 which was immobilized on protein G, and bound E. coli O157:H7 extracts on Immobilized Mab against E. coii O157:H7 were performed by atomic force microscopy (AFM). The detection limit of the SPR-based immunosensor for E. coli O157:H7 was found to be about $10^4$ cells/ml.

• 시스템엔지니어링워크숍
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• 통권4호
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• pp.5-10
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• 2004

ACTD(Advanced Concept Technology Demonstrations) exploit mature technologies to solve important military problems. A declining budget, significant changes in threats, and an accelerated pace of technology development have challenged our ability to adequately respond to rapidly evolving military needs. This work descibes ACTD processes, management, and ACTD programs case. It is presesyed a defense acquisition program applied ACTD.A scheme of the defense asquisition program using ACTD met military needs and technology readiness level is described.