• 대한족부족관절학회지
• /
• 제13권1호
• /
• pp.7-13
• /
• 2009

Purpose: The purpose of this study was to evaluate the effect of Sodium hyaluronate-Sodium carboxymethyl cellulose (HA-CMC) on tissue adhesion after tenorrhapy in tenotomized Achilles tendon of the Sprague-Dawley rat. Materials and Methods: Twenty-eight legs of 14 Sprague-Dawley rat were used in study. After tenotomy of the Achilles tendons, tenorrhaphies were performed. Simple tenorrhaphy without any other procedures were performed on the left Achilles tendons (control group), and additional HA-CMC injections were done prior to the tenorrhaphy on the right Achilles tendons (HA-CMC group). Gross and histological examinations were made to identify differences between the two groups, 1, 2, 6, 8, 10, 12 and 14 weeks respectively. Results: Distinct decrease in granulation tissues and adhesions were seen in the HA-CMC group during gross inspection at 6 and 8 week after the operation. On histological analysis of the HA-CMC group, although increased infiltrations of inflammation cells were observed during 1 week, less adhesion were seen at 6, 8 and 10 weeks after the operation. In HA-CMC group, superior healing processes were seen at 6, 8 and 10 weeks and less fibrotic changes, compared to control group, were seen at 2 and 6 weeks. Conclusion: Prevention of adjacent tissue adhesion was made possible through decrease in collagen deposition and fibrosis by injecting HA-CMC before tenorrhaphy of Achilles tendon. Also, histologically faster healing process of the collagen fibers within the Achilles tendon was observed.

• Journal of Pharmaceutical Investigation
• /
• 제34권6호
• /
• pp.477-482
• /
• 2004

The aim of the present study was to investigate the efficacy of a mixed gel formulation composed of sodium carboxymethyl cellulose and gellan gum (Na-CMC gel) for the prevention of adhesions after laminectomy. The anti-adhesive effect of the Na-CMC gel was tested in a controlled randomized study using an animal model of lumbar laminectomy. The animals (60 female Sprague-Dawley rats) were randomly allocated into two treatment groups to receive the Na-CMC gel on the injured area or no gel (control). The incidence of adhesions and their grade were blindly evaluated at 4, 8 and 12 weeks after surgery. The amount of scar tissue and tenacity were grossly reduced by the Na-CMC gel at postoperative 4, 8, and 12 weeks. The mean adhesion scores were 0.75, 1.25, and 1.38 at 4, 8, and 12 weeks in the gel-treated group, respectively. No significant inflammatory reaction was observed and the healing of wound was not affected by the Na-CMC gel. The Na-CMC gel reduced the amount of scar formation and tenacity in rat laminectomy model without affecting the healing of operation wound and other complications. Therefore, the Na-CMC gel may be the potential to prevent postsurgical adhesions in clinical state.

• Asia pacific journal of information systems
• /
• 제18권2호
• /
• pp.73-94
• /
• 2008

When individuals collaborated in virtual settings, communication is medicated through a variety of communication technologies, and is associated not only with communication effectiveness but also with socio-emotional interactions among group members. In this regards, scholars have examined how technology-mediated communication systems can be designed and used to facilitated communication interaction. However, the empirical results of the previous studies have revealed inconsistencies in the effects of communication media on users' behavioral or attitudinal responses, and on their viable effectiveness in organizations. Some studies claim that computer-mediated communication(CMC) is task-oriented but not suitable for emotional expression since it hinders close interpersonal interaction. On the other hand, some studies argue that individuals are able to develop interpersonal relationships more effectively in a CMC environment than in an FtF-environment. Due to the different perspectives, a theoretical gap exists, and it leads to the inconsistent research findings. The purpose of this paper is to combine the two different perspectives into single unified model, thereby providing a more realistic and comprehensive understanding about virtual collaboration. The present study here sought to answers the following questions with organizational communication perspective: What are the major components of virtual collaboration? What factors affect the performance of virtual collaboration? And what kind of managerial efforts should organization make in order to facilitate CMC media effectiveness in virtual collaboration? Although there is a certain belief that new media, namely technology-mediated communication support would create new opportunities, the problem of "how" or "why" has been an important question that is still not fully addressed. In this regards, we collectively reexamined previous literatures with major issues which are still controversial and integrated various theoretical activity within computer-mediated communication domain: task-oriented approach, socio-emotional approach, and evolutionary psychological approach. Our first contribution is to develop a framework for virtual collaboration by combining two different perspectives into a single unified model, providing a more realistic and comprehensive understanding. The second main contribution is the joint modeling of both social presence and cognitive effort, and the effects on two distinct but important communication outcomes(i.e., take performance and relational development). We tested the research hypotheses which were developed based on the various CMC theories using data gathered through a self-administered mail survey of 127 individuals of 69 virtual workgroups. The proposed model was supported, providing preliminary evidence that the tension between two opposite view should be integrated. The results show that the individual's psychological processes(social presence and cognitive effort) in a virtual environment significantly mediated the effect of CMC inputs (media richness, user adaptation, and shared contest) on the CMC outputs (task performance and relational development). Furthermore, this study shows that the lack of perceived media richness of CMC media can be complemented by user adaptation and shared context. Based on the results, we discuss how communication system should be designed and implemented so as to promote virtual interaction as well as how a virtual workgroup should be composed to complement the lack of media richness. A virtual collaboration using CMC media may create new value by overcoming the logistical constraints. On the other hand, it may also generate various managerial risks such as communicational depersonalization, process dissatisfaction, and low cohesion. Therefore, this study suggests that organization managers should carefully choose the CMC mediums and monitor individual member's cognitive and affective psychological processes during virtual collaboration to reduce potential risks in virtual collaboration.

• KSBB Journal
• /
• 제15권1호
• /
• pp.49-54
• /
• 2000

1.0%(w/v)의 CMC 담체는 고정화를 유지할 수 있는 점도를 가지며 0.1 M 이하의 양이온과 이온가교결합을 할 수 있는 농도이다. Luminometer tube내의 시료에 유동을 최소화함으로써 산소의 공급을 일정하게 하여 P. phosphoreum을 고정화 30분 후 bioluminescence intensity가 안정되어 바로 측정할 수 있는 장점을 가지고 있었다. 1.0%(w/v) CMC담체는 pH 6.92로 최적조건인 pH 7.0에 근접했으며, 발광기작에 필요한 산소전달(oxygen transfer)이 1.5%(w/v)~3.0%(w/v) CMC 담체보다 뛰어나 Bioluminescence intensity의 안정성을 부여하였다. Cr-화합물인 $Na_{2}CrO_{4}$, $K_{2}CrO_{4}$, $CrO_{3}$, CrK$(SO_4)_{2}$ 및 $CrCl_{3}$의 CMC담체에 대한 민감도는 $\gamma$값을 이용해서 $EC_{50}$값으로 나타내었을 때 $Na_{2}CrO_{4}$, $K_{2}CrO_{4}$, CrK$(SO_4)_{2}$ 및 $CrCl_{3}$ 의 $EC_{50}$값이 1.0%(w/v)CMC에서는 5.4~16.3 g/L으로 1.5%(w/v)~3.0%(w/v) CMC에서는 6.2~555.9 g/L의 범위로 나타났다. 이것은 1.0%(w/v) CMC가 낮은 독성 농도에서 bioluminescence intensity가 50% 감소함을 알 수 있고, 상관계수($R^2$)가 0.911~0.990 으로 높게 산출되었다. 따라서 1.0%(w/v) CMC 담체가 P. phosphoreum의 biolumincsene에 안정성을 주었으며, 독성물질에 가장 민감하다는 것을 알 수 있었다.

• 한국식품조리과학회지
• /
• 제24권5호
• /
• pp.636-644
• /
• 2008

식빵의 식감향상과 노화 방지에 hydrocolloid의 첨가가 미치는 영향을 파악하기 위해 5종의 hydrocolloid(xanthan gum, guar gum, sodium alginate, k-carrageenan, CMC)를 첨가량을 달리하여 식빵을 제조하고, 시료반죽의 호화특성과 제조 식빵의 관능평가를 실시하였다. 또한 선정된 2종의 hydrocolloid(CMC, k-carrageenan)첨가 식빵의 노화속도와 유형을 파악하고자 저장기간에 따른 경도변화를 Avrami 식으로 분석하고 또한 DSC thermogram 분석도 실시하였다. 대조군에 비해 hydrocolloids 첨가군이 전반적으로 호화개시온도가 하강하였고, 최고 점도는 증가하였다. 노화의 지표로 사용되는 치반점도(setback)와 강하점도(breakdown)은 hydrocolloids 첨가 시 특히 CMC(0.6%, 1%), xanthan gum(1%), k-carrageenan(1%) 첨가 시 낮게 나타나 노화 지연효과를 추측할 수 있었다. 관능평가에서 1% 첨가 시에는 관능적 경도가 대조군에 비해 유의적으로 높게 나타나서 노화 측정 실험에서 제외하였다. 그 외 색상 강도와 뒷맛 강도에서 대조군과 첨가군의 유의적 차이는 나타나지 않았다. 제조된 식빵시료의 제조 후 15일간 경과 시의 경도 변화에서는 CMC와 k-carrageenan 첨가 시료의 경우 대조군에 비해 경도의 증가폭이 낮게 나타나 식빵의 경도 증가를 억제하는 것을 확인할 수 있었다. Avrami 모형에 의한 초기 경도를 고려한 비율로 노화도를 계산하면 대조군이 3.3배, CMC는 3.2배, k-carrageenan은 2.8배의 경도 증가폭을 나타내 k-carrageenan 첨가군의 노화비율이 낮은 것으로 나타났다. DSC 측정에서도 저장기간에 따른 엔탈피의 증가폭이 k-carrageenan 첨가군이 가장 낮은 수준을 나타내 경도 측정 및 Avrami 모형과 일치하는 결과를 나타냈다. 향후 제빵 시 노화 지연 효과를 위해 좀 더 다양한 첨가 수준에서의 노화 속도와 유형을 파악하는 것이 필요하리라 여겨진다.

• 폴리머
• /
• 제34권4호
• /
• pp.363-368
• /
• 2010

창상 회복에 있어 적절한 산성의 환경은 세균의 증식을 막을 뿐만 아니라 세포의 활성도를 증가시키고 섬유아 세포의 증식을 촉진시키며 배열을 고르게 유지하여 결국 성숙된 상피화를 가져오게 된다. 본 연구에서는 펙틴과 CMC 의 다양한 조성으로 이루어진 드레싱제를 이용하여 펙틴과 CMC의 조성비와 이에 따른 pH의 변화가 신선창상, 감염 창상 및 화상에 있어 창상치유속도, 상피화 정도 및 콜라겐 침착 등에 미치는 영향과 이의 새로운 드레싱 재료로서의 가 능성을 알아보기 위해 동물실험을 시행하였다. 실험 결과로부터 pH 4.67인 펙틴/CMC＝16/19 군이 급성창상의 창상 회복에 있어 창상의 수축률, 치유율 및 상피화율이 다른 군에 비해 높은 정도를 보여 가장 우수한 창상 치유 효과를 보임을 알 수 있었다.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
• /
• pp.134-134
• /
• 2016

CMC(Ceramic Matrix Composites)는 $1500^{\circ}C$ 이상의 고온에서 내열성, 내산화성, 내식성이 우수하여, 초음속 비행체, 가스터빈 엔진 및 원자로용 초고온 부품 등에 수요가 증가하고 있다. 하지만 이러한 특성은 비산소 환경에 국한되는 것으로 약 $400^{\circ}C$ 이상의 산화 분위기에는 탄소섬유가 산화되는 문제로 인하여 적용의 한계를 가지고 있다. 따라서 CMC의 적용범위 확대를 위하여 내산화 코팅으로 CMC의 초고온 산화특성을 개선하는 것이 필수적이며, 장시간 초고온 산화환경 분위기에서 사용되기 위하여 안정적인 코팅기술이 최근 기술개발의 핵심현안으로 부각되고 있다. 본 연구에서는 pack cementation 공정을 이용하여 내산화성이 우수한 SiC 코팅층을 제조하였다. Pack cementation 공정에 사용된 코팅 분말은 57wt.% SiC, 30wt.% Si, 3wt.% B, 10wt.% Al2O3의 비율로 혼합된 것이다. 실험은 3D 직조된 CMC 모재를 혼합분말 내에 침적한 후, Ar 분위기에서 $1600^{\circ}C$, 4~12시간 반응시켜 수 마이크론 두께의 SiC 코팅층을 형성하였다. 더 우수한 산화 특성을 부여하기 위하여 pack 처리된 CMC 표면에 초고온 세라믹인 TaC 소재를 진공플라즈마 코팅 공정으로 적층시켰다. 제조된 코팅층을 SEM, XRD를 이용하여 미세구조 및 결정구조를 분석하였으며, pack cementation에 따른 내산화 특성을 비교 분석하고자 $2000^{\circ}C$에서 산화 실험을 진행하였다. 산화 실험 이후 미세구조 및 결정구조 분석으로 산화거동을 규명하고자 하였다.

• 한국환경과학회지
• /
• 제3권1호
• /
• pp.57-64
• /
• 1994

On the basis of the principle of Bratch's electronegativity equalization, we calculated group partial charges and group electronegativities for nonionic surfactants with Pauling's elecoonegativity parameters by using numerical calculation method. From calculated outputs we have investigated structural stability of micelle, characteristics of hydrophilic and hydrophobic groups, and relation between CMC(Critical Micelle Concentraion) and group partial charge and group electronegativity of hydrophilic and hydrophobic groups for nonionic surfactants. We have known that CMC by micelle formation depends upon group partial charge and group electronegativity of hydrophilic and hydrophobic groups for surfactants. Also, the structural stability of micelle in H2O solution is related to the electric double layer by the hydrophilic group of nonionic surfactants with H atoms in water CMC is diminished by the decrease of repeating units in hydrophilic group at constant hydrophobic group and is diminished by the increments of alkyl chains in hydrophobic group at constant hydrophilic group for nonionic surfactants. In conclusion, CMC is diminished because there is no electrostatic repulsion and is diminished of Debye length by the increments of partial charge of hydrophobic group.

• 경영과학
• /
• 제28권1호
• /
• pp.91-105
• /
• 2011

Among various types of creativity, team creativity has been always receiving attention from both practitioners and researchers because most of works are done in a team format in organizations. Therefore, it would be the best way for corporate performance to increase when team creativity is managed carefully to increase in a steadfast way. Though there are lots of ways to grow team creativity, this study explores the issue of increasing the team creativity by adopting CMC (computer-mediated communication) and exploration and exploitation, which were studied separately, but never analyzed together in the same research framework. Experiments to prove the validity of the research questions are based on ABM (Agent-Based Modeling) simulation. Netlogo language was adopted to build a prototype engine for the simulation engine. Experiment results revealed that in the short-term, both broad CMC mode with high exploration and exploitation, and local CMC mode with high exploration and exploitation result in higher team creativity than other types of combination. However, in the long run, broad CMC mode yields higher team creativity level than local CMC mode.

• Fisheries and Aquatic Sciences
• /
• 제19권4호
• /
• pp.15.1-15.5
• /
• 2016

Apparent digestibility coefficients (ADCs) of dry matter, crude protein, crude lipid, nitrogen-free extract, and energy in selected carbohydrate sources including wheat flour (WF), ${\alpha}-potato$ starch (PS), ${\alpha}-corn$ starch (CS), Na alginate (AL), dextrin (DEX), and carboxymethyl cellulose (CMC) were determined for olive flounder. The olive flounder averaging $150{\pm}8.0g$ were held in 300-L tanks at a density of 30 fish per tank. Chromic oxide was used as the inert marker. Feces were collected from the flounder by a fecal collector attached to a fish rearing tank. Apparent dry matter and energy digestibilities of flounder fed WF, PS, CS, and DEX diets were significantly higher than those of fish fed AL and CMC diets. Apparent crude protein digestibility coefficients of flounder fed PS and CS diets were significantly higher than those of fish fed AL, DEX, and CMC diets. Apparent crude lipid and nitrogen-free extract digestibility coefficients of flounder fed PS and DEX diets were significantly higher than those of fish fed WF, CS, AL, and CMC diets. The present findings indicate that PS and DEX could be effectively used as dietary carbohydrate energy compared to WF, CS, AL, and CMC for olive flounder.