• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2160-2164
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• 2007

In this study, the mechanism of enhanced thermal conductivity is elucidated on the bases of both electric double layer (EDL) and kinetic theory. A novel expression for the thermal conductivity of nanofluids is proposed and verified by applying to $Al_2O_3$ nanofluids with regard to various temperatures, volume fractions and particle sizes. In dilute nanofluids, the effects of Brownian motion and particle interaction on enhancing the thermal conductivity of nanofluids are quite comparable while the effect of particle interaction due to EDL is more prominent in dense nanofluids. The model presented in this paper shows that particle interaction due to the electrical double layer is the most responsible for the enhancement of thermal conductivity of nanofluids.

• 생명과학회지
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• 제20권4호
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• pp.572-577
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• 2010

본 연구에서 60 주령된 쥐를 대상으로 8 주간 트레드밀 운동강도와 근섬유 유형에 따른 apoptosis 관련 인자를 연구하였다. 결론적으로 노후된 쥐의 apoptosis 관련 인자는 운동강도와 근육유형에 따라 차이가 났다. EDL이 Soleus보다 apoptosis인자의 변화가 운동강도에 의해 더 민감하게 나타났다. 또한 casepase-3의 발현은 고강도 운동에서 나타났으나 DNA 절편화는 나타나지 않았기에 실질적인 apoptosis는 발생되지 않았다. 이는 노후된 개체의 운동 수행방법으로 고강도 운동은 적합하지 않으며, 고강도 운동상태를 지속할 경우 근섬유의 apoptosis를 유도할 가능성이 있다는 것을 시사한다. 그러므로 추후 실험에서는 운동시간과 빈도에 의한 apoptosis의 time-course impact 관찰과 외재적 경로(caspase independent apoptosis)에서의 apoptosis 관련 단백질 변화에 대한 연구를 통하여 노화에 의한 근손실의 원인 규명이 요구된다.

• International Journal of Internet, Broadcasting and Communication
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• 제9권2호
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• pp.64-69
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• 2017

The abstract should summarize the contents of the paper and written below the author information. Use th In Wide-area Wireless Sensor Networks, network lifetime is short due to energy consumption due to transmission distance. To improve this, we divide the sensor field into layers and reduce transmission distance through multi-hop transmission. However, there is a problem in that the transmission rate drops because there is no Cluster Head in the layer, or the transmission distance increases due to the layer, and energy is wasted. There are DL-LEACH and EDL-LEACH as Protocols to improve this. DL-LEACH uses either single-hop transmission or multi-hop transmission depending on the situation. As a result, the transmission distance is optimized, thereby reducing energy consumption. In case of EDL-LEACH, it is proposed to improve the data rate in DL-LEACH. It is the same as DL-LEACH, but the Cluster Head is mandatory for all layers to improve the transmission rate. Although there is no Cluster Head for each layer, the transmission rate is improved, but the network life is shortened. In this paper, we try to improve the network lifetime while maintaining the EDL-LEACH transmission rate. The shortened network lifetime is due to Cluster Head overload near the base station. To improve this, the Cluster Head distribution method is improved and the network lifetime is improved.

• The Journal of Korean Physical Therapy
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• 제14권2호
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• pp.16-25
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• 2002

Low energy laser irradiation(LELI) therapy in physical therapy is widespread but the mechanisms are not fully understood. The purpose of the present study was to examine the epidermal growth factor(EGF)'s expression within lumbar spinal cord which corresponding with crushed extensor digitorum longus(EDL) of rats after low-power laser irradiation applied. After a crushed injury on the right EDL, low-power laser irradiation was applied by using 2000mW, 2000Hz, 830nm GaAlAs(Gallium-aluminum-arsenide) semiconductor diode laser. The laser treatment was performed with 10 minutes daily for 3days. After EDL crush injury, EGF immunoreactive positive neurons in experimental group were progressively decreased from the first to third days. Especially 1 day subgroup is highly expressed in dorsal horn(Lamina I, II, III) and around of central cannal of spinal cord(Lamina VII). Control group was only expressed slightly at 3 days. This study suggests that LELI stimulate that release and migration of EGF in spinal cord, which distict to wound site, therfore promote wound healing of EDL crush injury.

• 대한치과교정학회지
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• 제42권2호
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• pp.64-72
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• 2012

Objective: The aims of this study were to examine whether a passive stretch stimulus by means of a functional appliance induces changes in the fiber composition of masticatory muscles and whether these changes are similar to the changes in stretched limb muscle fibers by using RT-PCR, western blot, and immunohistochemical assays. Methods: Five male New Zealand White rabbits were fitted with a prefabricated inclined plane on the maxillary central incisors to force the mandible forward (- 2 mm) and downward (- 4 mm). Further, 1 hind limb was extended and constrained with a cast so that the extensor digitorum longus (EDL) was stretched when the animal used the limb. The animals were sacrificed aft er 1 week and the masseter, lateral pterygoid, and EDL were processed and compared with those from control animals (n = 3). Results: The stretched EDL had a significantly higher percentage of slow fibers, whereas the stretched masticatory muscles did not show changes in the composition of the major contractile proteins aft er 7 days. Conclusions: The transition of fiber phenotypes in response to a stretch stimulus may take longer in the masticatory muscles than in the limb muscles.

• Journal of Microbiology and Biotechnology
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• 제24권3호
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• pp.401-407
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• 2014

Quorum sensing and the stringent response are well-known regulation systems for the expression of virulence genes in enterohemorrhagic Escherichia coli (EHEC). However, how these two systems interact is not well known. E. coli strains with mutations in two regulation systems, ${\Delta}luxS$ (ECM101) and ${\Delta}luxS{\Delta}relA{\Delta}spoT$ (ECM201), and the ${\Delta}luxS$ complement strain to ECM201 (ECM202) were created from EHEC O157:H7 EDL933 to investigate how the regulatory systems interact. The phenotypic changes of the mutant strains were characterized and compared with the wild type. The mutant strains exhibited no obvious growth defects, although acid resistance and cellular cytotoxicity were decreased significantly in all the mutant strains. Phenotypic characterization revealed that mutations in the stringent response system (ECM201 and ECM202) influenced the metabolic (defective utilization of arabinose and L-sorbose) and enzymatic activities (decreased trypsin activity, and increased ${\alpha}$-glucosidase activity). In contrast, the quorum sensing system mutant (ECM101) did not display these phenotypes. The motility of the quorum sensing system mutant (ECM101) was unchanged, but mutation in the stringent response system influenced the motility. Our results suggest that quorum sensing interacts with the stringent response regulation system.

• Journal of Nutrition and Health
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• 제21권4호
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• pp.242-252
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• 1988

Branched-chain 아미노산이인 leucine이 골격근육의 단백질 합성을 촉진하는 요소로 보고되어 왔다. 이러한 역할은 다른 아미노산도 나타낼 수 없는 특이한 것이나 생체로부터 분리된 근육(isolated muscle system)에서 라는 제한된 실험조건하에 얻어진 결과에 바탕하므로, 본 연구는 생체내에서 leucine이 단백질의 생합성에 미치는 영향을 조사하고자 시도되었다. 실험동물은 정상으로 먹이를 먹인 또는 하루 굶게된 주로 leucine군과 비교군으로 나누었다. Leucine군은 80 또는 $160\mu\textrm{moles}$의 leucine을 복강으로 한번 주사하여 주입받았고 비교군에는 생리적 식염수를 같은 방법으로 주입했다. 단백질 합성속도는 $^{14}\textrm{C}-tyrosine을 주사한 후 근육의 단백질에 혼입된 $^{14}\textrm{C}의 량으로 측정하였다. 본 연구에 이용된 근육은 두가지 형태의 뒷다리 근육 즉 oxidative형 soleus와 glycolytic형 extensor digitorium longus(EDL)와 plataris근육이었다. 만 하루 굶게된 뒤의 EDL과 plantaris 근육은 $160\mu\textrm{moles}$의 leucine에 의해 단백질 합성 속도가 24%, 29% 씩 각각 상승했다. 하루 굶게된 쥐의 soleus근육과 정상으로 먹인 쥐의 어느 근육도 첨가된 leucine에 대해 반응을 보이지 않았다. Leucine에 의해 단백질 합성 속도가 상승된 근육은 굶게되므로 합성속도가 정상군의 54%로 떨어졌고 soleus근육은 정상군의 78%에 상당한 단백질 합성 능력을 가지고 있었다. 따라서 생체로부터 분리된 근육에서 동물의 영양상태나 홀몬 분비의 정상여부에 관계없이 leucin이 단백질 생합성 속도를 상승시키는 현상은 생체내에서 재현되지 않았다. 본 연구결과는 식이 제한등으로 인한 스트레스에 민감하게 반응하여 근육내 생성 활동이 저하된 특수한 상태에서만 leucine은 골격근육의 질소 보유능력을 상승시키리라는 것을 시사한다.

• 한국정보시스템학회:학술대회논문집
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• 한국정보시스템학회 2001년도 추계학술대회 발표논문집:차세대 전상거래 시대의 비즈니스전략
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• pp.98-109
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• 2001

• 무역상무연구
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• 제11권
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• pp.491-521
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• 1998

• 무역상무연구
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• 제11권
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• pp.523-550
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• 1998