• Biomolecules & Therapeutics
• /
• 제30권2호
• /
• pp.170-178
• /
• 2022

The airway epithelium is equipped with the ability to resist respiratory disease development and airway damage, including the migration of airway epithelial cells and the activation of TLR3, which recognizes double-stranded (ds) RNA. Primary cilia on airway epithelial cells are involved in the cell cycle and cell differentiation and repair. In this study, we used Beas-2B human bronchial epithelial cells to investigate the effects of the TLR3 agonist polyinosinic:polycytidylic acid [Poly(I:C)] on airway cell migration and primary cilia (PC) formation. PC formation increased in cells incubated under serum deprivation. Migration was faster in Beas-2B cells pretreated with Poly(I:C) than in control cells, as judged by a wound healing assay, single-cell path tracking, and a Transwell migration assay. No changes in cell migration were observed when the cells were incubated in conditioned medium from Poly(I:C)-treated cells. PC formation was enhanced by Poly(I:C) treatment, but was reduced when the cells were exposed to the ciliogenesis inhibitor ciliobrevin A (CilioA). The inhibition of Beas-2B cell migration by CilioA was also assessed and a slight decrease in ciliogenesis was detected in SARS-CoV-2 spike protein (SP)-treated Beas-2B cells overexpressing ACE2 compared to control cells. Cell migration was decreased by SP but restored by Poly(I:C) treatment. Taken together, our results demonstrate that impaired migration by SP-treated cells can be attenuated by Poly(I:C) treatment, thus increasing airway cell migration through the regulation of ciliogenesis.

• 한국항행학회논문지
• /
• 제27권6호
• /
• pp.877-883
• /
• 2023

선박의 안전 운항과 해양수산 양식장 관리를 위해 해양수산 빅데이터 구축에 필요한 해양수산 양식장의 경계를 추출한 데이터 셋은 어장 허가 구역과의 일치 여부 조사를 통해 선박의 운항 경로에 불법 설치 시 장애물 정보를 미리 제공할 수 있다. 또한, 해양 사고 등에 의한 피해보상을 위해 필요한 양식장 조업 여부도 파악할 수 있으며, 해당 지자체에서는 어장도와의 중첩 비교를 통해 어장 관리 등에 사용할 수 있다. 선박의 안전 운항을 위한 전자해도에 물표 표시를 통해 운항 경로상의 장애물 파악에 필요한 기초 데이터로써 활용이 높다. 이 연구에서는 양식장의 경계 추출을 위해 충분한 공간해상도를 가지며 짧은 주기로 반복하여 촬영하는 유럽항공우주국 (ESA; europe space agency)의 Sentinel-2 위성영상 자료를 사용하였다. 영상 이미지에서 양식장의 주기별 현황 데이터의 생산을 위해 해상의 구역별 데이터를 부산권, 울산권, 거제·창원권, 고성·통영권, 남해·사천권의 5개 관리 구역으로 나누어 처리하였으며, 구역별 위성영상의 수집과 영상의 강조 처리 과정을 거쳐 양식장의 경계 데이터와 메타정보를 추출하였다.

• 청정기술
• /
• 제30권1호
• /
• pp.23-27
• /
• 2024

Bismuth는 적절한 작동 전압(0.8 V)과 높은 체적 용량(3,765 mAh cm^-3) 때문에 Li-ion battery (LIBs)의 유망한 음극소재로 여겨진다. 그럼에도 불구하고 Bi의 Li과의 합금화 반응 중 필연적인 부피 팽창은 심각한 용량 손실과 셀 파괴를 초래한다. 이를 해결하기 위해 본 논문에서는 N이 도핑된 탄소에 내장된 비스무트 합금 나노 입자(Bi@NC)의 복합체를 간단한 열분해 방법을 통해 제조하였다. 나노 크기의 Bismuth 합금은 단축된 Li⁺ 이온 확산 경로를 통해 반응 동역학을 향상시킬 수 있다. 또한, N 도핑된 탄소 코팅은 Li⁺ 이온과의 확장된 합금/탈 합금 반응 동안 Bismuth의 부피 변화를 효과적으로 완충하고 효과적인 전도성 네트워크를 유지한다. 열 중량 분석한 결과 매우 높은 Bismuth 합금 로딩(80.9 wt%)을 보여줬음에도 불구하고 100 cycles까지 315 mAh g^-1 용량을 유지하였다.

• 자원환경지질
• /
• 제34권6호
• /
• pp.507-522
• /
• 2001

통영광산은 첨열수광상으로서 능망간석 , 백운모, 일라이트, 황철석 , 방연석 , 황동석 , 섬아연석 , 아칸다이트 및 헤사이트등의 광물을 수반하는 초기의 광석광물 침전시기와 후기의 맥석광물 침전시기로 구분된다. 초기는 반복적인 대상구조를 띠고, 황화광물이 침전된 시기로서 텔루리움 광물과 함께 엘렉트럼이 산출된다. 후기에는 주로 단산염 광물과 천금속광물이 침전되었다. 통영 열수계에서 광화단계에 따른 상이한 열수유체의 변천과정을 구체적으로 규명하기 위하여 프로그램 CHILLER를 이용한 수치모델링이 실시되었다. 반응경로 모델링은 28$0^{\circ}C$에서 모암인 안산암과의 반응을 비롯하여, 27$0^{\circ}C$에서 12$0^{\circ}C$까지의 단순한 등압 냉각, 비등과 지하수의 혼입에 따른 희석 및 압력파 온도가 감소되는 조건에서 수행하였다. 모델링 결과 초기 광화유체는 산성용액(pH=5.7)으로 상대적으로 높은 염농도와 금속원소 함량이 높다. 장화유체 내의 금의 함량은 열수계의 천금속원소 총량과 황화물의 활동도에 의해 지배된다. 통영 천열수계에서의 광화작용은 천부에서 일어난 참화유체의 비등과 이에 수반된 가열된 지하수의 흔입에 의한 반응경로를 반영하며, 현미경에서 관찰된 광물공생 특성과 모델링에 의한 침전광물의 조합 및 엘렉트럼의 화학조성 등에서 동일한 경향을 나타낸다. 이러한 유사성은 Te 함유하는 천열수 금 . 은광상이 열수계에서의 비등과 유체혼합(희석)에 의해 생성되었음을 지시한다. 반응경로 모델링 연구는 광상성인을 이해하는 중요한 수단이며, 유사한 지질환경에서의 광강탐사에 유용한 자료로 활용될 것으로 생각된다.

• 한국정보통신학회논문지
• /
• 제20권6호
• /
• pp.1163-1170
• /
• 2016

본 논문은 ISO/IEC 29192-2 경량 암호 표준으로 지정된 초경량 블록암호 알고리듬 PRESENT의 하드웨어 구현에 대해 기술한다. PRESENT 암호 프로세서는 80, 128비트의 마스터키 길이와 ECB, CBC, OFB, CTR의 4가지 운영모드를 지원하도록 설계되었다. 마스터키 레지스터를 갖는 on-the-fly 키 스케줄러가 포함되어 있으며, 저장된 마스터키를 사용하여 평문/암호문 블록의 연속적인 암호/복호화 처리가 가능하다. 경량화 구현을 위해 80, 128 비트의 키 스케줄링 회로가 공유되도록 최적화하였다. 라운드 블록을 64 비트의 데이터 패스로 설계하여 암호/복호화의 라운드 변환이 한 클록 사이클에 처리되도록 하였다. PRESENT 암호 프로세서를 Virtex5 FPGA로 구현하여 정상 동작함을 확인하였다. $0.18{\mu}m$ 공정의 CMOS 셀 라이브러리로 합성을 한 결과, 8,100 gate equivalents(GE)로 구현되었으며, 최대 454 MHz의 클록 주파수로 동작하여 908 Mbps의 처리율을 갖는 것으로 평가되었다.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
• /
• pp.993-994
• /
• 2008

Electrochromic (EC) devices are capable of reversibly changing their optical properties upon charge injection and extraction induced by the external voltage. The characteristics of the EC device, such as low power consumption, high coloration efficiency, and memory effects under open circuit status, make them suitable for use in a variety of applications including smart windows and electronic papers. Coloration due to reduction or oxidation of redox chromophores can be used for EC devices (e-paper), but the switching time is slow (second level). Recently, with increasing demand for the low cost, lightweight flat panel display with paper-like readability (electronic paper), an EC display technology based on dye-modified $TiO_2$ nanoparticle electrode was developed. A well known organic dye molecule, viologen, was adsorbed on the surface of a mesoporous $TiO_2$ nanoparticle film to form the EC electrode. On the other hand, ZnO is a wide bandgap II-VI semiconductor which has been applied in many fields such as UV lasers, field effect transistors and transparent conductors. The bandgap of the bulk ZnO is about 3.37 eV, which is close to that of the $TiO_2$ (3.4 eV). As a traditional transparent conductor, ZnO has excellent electron transport properties, even in ZnO nanoparticle films. In the past few years, one-dimension (1D) nanostructures of ZnO have attracted extensive research interest. In particular, 1D ZnO nanowires renders much better electron transportation capability by providing a direct conduction path for electron transport and greatly reducing the number of grain boundaries. These unique advantages make ZnO nanowires a promising matrix electrode for EC dye molecule loading. ZnO nanowires grow vertically from the substrate and form a dense array (Fig. 1). The ZnO nanowires show regular hexagonal cross section and the average diameter of the ZnO nanowires is about 100 nm. The cross-section image of the ZnO nanowires array (Fig. 1) indicates that the length of the ZnO nanowires is about $6\;{\mu}m$. From one on/off cycle of the ZnO EC cell (Fig. 2). We can see that, the switching time of a ZnO nanowire electrode EC cell with an active area of $1\;{\times}\;1\;cm^2$ is 170 ms and 142 ms for coloration and bleaching, respectively. The coloration and bleaching time is faster compared to the $TiO_2$ mesoporous EC devices with both coloration and bleaching time of about 250 ms for a device with an active area of $2.5\;cm^2$. With further optimization, it is possible that the response time can reach ten(s) of millisecond, i.e. capable of displaying video. Fig. 3 shows a prototype with two different transmittance states. It can be seen that good contrast was obtained. The retention was at least a few hours for these prototypes. Being an oxide, ZnO is oxidation resistant, i.e. it is more durable for field emission cathode. ZnO nanotetropods were also applied to realize the first prototype triode field emission device, making use of scattered surface-conduction electrons for field emission (Fig. 4). The device has a high efficiency (field emitted electron to total electron ratio) of about 60%. With this high efficiency, we were able to fabricate some prototype displays (Fig. 5 showing some alphanumerical symbols). ZnO tetrapods have four legs, which guarantees that there is one leg always pointing upward, even using screen printing method to fabricate the cathode.

• 대한교통학회지
• /
• 제22권7호
• /
• pp.91-98
• /
• 2004

본 연구는 통행자들을 실시간 교통정보의 유무외에 제공받는 교통정보의 내용에 따라서 구분한 다계층 통행배정모형을 정립하고자 한다. 이를 통해 네트워크 및 수요변화에 대응할 수 있는 우수한 교통정보제공전략인 분산환류전략(Decentralized Feedback Strategy ; DFS)의 핵심사항인 분산계수결정모형을 제시하고 ITS의 중요한 기술적 요소들(VMS위치, 정보제공주기, 정보제공영역 등)에 대한 판단기준을 정립하고자 한다. 이를 위하여 연동적 시간대 분석기법 (Rolling Horizon implementation ; RHI)을 활용한 다계층 동적통행배정모형을 개발하고 차량내탑재장치를 활용한 주행중 정보제공전략으로서 분산환류전략(DFS)의 적용성 및 효과성을 평가하고자 하였다. 본 연구에서는 차량내 탑재장치를 중심으로 교통정보를 제공받는 집단에 대해서 분석을 수행하였다. 이때 정보의 내용에 따라 동적 최단경로안내를 받는 그룹과 DFS에 의한 경로정보를 안내받는 그룹으로 나누어 다계층 동적통행배정 모형을 구성하였다. DFS의 적용을 위하여 정보대상노드에서 목적지까지 경로를 모두 탐색한 뒤 이들 경로에 대한 통행시간정보를 이용하여 통행자들의 인지통행비용이 같아지도록 교통류 분산계수를 설정하였다. 또한 이러한 분산계수가 적용되는 통행자를 구별하기 위하여 연동적 시간대분석기법(Rolling Horizon Imlementation)을 활용하여 동적통행배정을 수행하였다. 분석결과 유고상황시 DFS의 네트워크 총통행시간 개선효과를 확인할 수 있었다.

• Journal of Plant Biology
• /
• 제2권1호
• /
• pp.1-12
• /
• 1959

1) The comparative studies of the quantitative measurement of growth characteristics and utilization of substrates by Euglena gracilis var. bacilla 10616 in the light and in darkness have been carried out. Eodogenous respiration, effect of respiratory inhibitors and responses to the added substrates for the exogenous respiration are also investigated. 2) All cultures are grown in the open air under the continuous illumination of fluorescent light of 3500 lux at room termperature, the growth rate of the culture in the basal medium added 0.5% lactate is found to be the highest. The growth rate decreases successively for the cultures of 0.5% sucinate, 0.5% Na-acetate, 0.5% malate, and control. There is no growth in the basal meidum added 0.5% butyrate and 0.5% hydroquinone. The similar results are obtained for the mentioned cultures in the darkness. However, the growth rate in basal medium added 0.5% glucose and 0.5% sucrose does seem to increase in the darkness unlike the illumination. 3) The endogenous rate of respiration for the organism cultured photosynthetically is about 12.94ul 02/mg/hr, in basal medium and the respiratory quotient is about 0.84. The rate is decreased by starvations to 6.5ul 02/mg/hr, about to a half, but the respiratory quotient does net change. 4) The oxygen consomption during initial 2 hours in suspending solution ranging from pH 4.5 to pH 9.3 is highest at pH 4.5 in which the algae had grown, at pH 5.5 and at pH 6.9. 5) Endogenous respiration of the cells is strongly inhibited by 0.1M of potassium cyanide, malomic acid, sodium fluoride and iodo-acetic acid. It is also strongly inhibited by 0.01M of potassium cyanide. 6) The respiratory response to added substrates for the exogenous respiration in the organism is coincided with the rate in the basal medium added the substrate in light and in darkness, whether the cells are fed or starved. 7) According to the results of this study, there seems to be the flexibility of the interconversion between photosynthesis and chemosynthesis, heterotropic mode of metabolism, in Euglena gracilis var. bacillaris, and that this organism utilizes the lactate most. It also may be suggested that the enayme systems linked in the each steps of Embden-Myerhof-Parnas path way and TCA cycle seem to exist in this organism.

• Clinical and Experimental Reproductive Medicine
• /
• 제38권1호
• /
• pp.47-52
• /
• 2011

Objective: To determine whether characteristics of sperm motility obtained by computer-assisted sperm analysis (CASA) could predict pregnancy after intrauterine insemination (IUI) in couples with unexplained infertility. Methods: Three hundred eighty-three cycles of intrauterine insemination with superovulation were retrospectively analyzed. Semen analysis was performed with CASA before and after swim-up and the parameters were compared between pregnant and non-pregnant women. Results: The pregnancy rate per cycle was 14.1%. Pregnant and non-pregnant women were comparable in terms of age, infertility duration, the number of dominant follicles. While sperm concentration, motility, and parameters such as average path velocity (VAP) and percentage rapid (RAPID) before semen preparation were significantly different between the pregnancy and non-pregnancy groups, there were no differences in sperm parameters when comparing the two groups after preparation. Using a receiver operating characteristic curve to measure sensitivity and specificity, the optimal threshold value for the predictors of pregnancy was revealed to be a concentration of ${\geq}111{\times}10^6/mL$, a motility of ${\geq}$ 51.4%, and RAPID ${\geq}$ 30.1% before preparation for IUI. Conclusion: Sperm parameters including concentration, motility, and RAPID before sperm preparation could have predictive value for pregnancy outcome after intrauterine insemination with superovulation in couples with unexplained infertility, and would be helpful when counseling patients before they make the decision to proceed with IVF/ICSI-ET.

• Clinical and Experimental Reproductive Medicine
• /
• 제44권3호
• /
• pp.132-140
• /
• 2017

Objective: Correlations between semen parameters and sperm DNA fragmentation index (DFI) were investigated to identify characteristics of sperm without DNA damage that could be used in selecting sperm for intracytoplasmic sperm injection (ICSI). Pregnancy outcomes were compared to determine whether in vitro fertilization (IVF) or ICSI is a better choice for patients who have sperm with a high-DFI. Methods: Semen analysis was carried out in 388 patients who visited our IVF center for the first time to investigate correlations between sperm DFI and semen parameters. In addition, 1,102 IVF cycles in 867 patients were carried out in the present study; 921 cycles in the low-DFI group (DFI < 30%) and 181 cycles in the high-DFI group ($DFI{\geq}30%$). Both the low- and high-DFI groups were subdivided into IVF and ICSI cycle groups. Results: Sperm DFI showed significant inverse correlations with sperm motility (r = -0.435, p< 0.001) and morphology (r = -0.153, p< 0.05). Sperm DFI also showed significant correlations with rapid motility (r = -0.436, p< 0.001), and the kinetic parameters of average-path velocity (r = -0.403) and linearity (r = -0.412). Although there was no significant difference in the pregnancy rates between IVF (48.6%) and ICSI (44.8%) in the low-DFI group, the pregnancy rate of ICSI cycles (44.8%, p< 0.05) was significantly higher than IVF cycles (25.0%) in the high-DFI group. No significant difference was observed in the abortion rates between the low-DFI (52 of 921, 5.6%) and high-DFI groups (7 of 181, 3.8%). Conclusion: ICSI is a better choice than IVF for improving the pregnancy outcomes of patients who have sperm with a high DFI.