석탄바닥재로 제조된 결정화 유리의 물리적 특성에 미치는 Li₂O 첨가 영향

엄누리,강승구,Um, Noo-Li,Kang, Seung-Gu 한국재료학회 2010 한국재료학회지 Vol.20 No.2

Glass-ceramics were fabricated by heat-treatment of glass obtained by melting a coal bottom ash with $Li_2O$ addition. The main crystal grown in the glass-ceramics, containing 10 wt% $Li_2O$, was $\beta$-spodumene solid solution, while in $Li_2O$ 20 wt% specimen was mullite, identified using XRD. The activation energy and Avrami constant for crystallization were calculated and showed that bulk crystallization behavior will be predominant, and this expectation agreed with the microstructural observations. The crystal phase grown in $Li_2O$ 10 wt% glass-ceramics had a dendrite-like shaped whereas the shape was flake-like in the 20 wt% case. The thermal expansion coefficient of the $Li_2O$ 10 wt% glass-ceramics was lower than that of the glass having the same composition, owing to the formation of a $\beta$-spodumene phase. For example, the thermal expansion coefficient of $Li_2O$ 10 wt% glass-ceramics was $20\times10^{-7}$, which is enough for application in various heat-resistance fields. But above 20 wt% $Li_2O$, the thermal coefficient expansion of glass-ceramics, on the contrary, was higher than that of the same composition glass, due to formation of mullite.

Overproduction of recombinant <i>E. coli</i> malate synthase enhances <i>Chlamydomonas reinhardtii</i> biomass by upregulating heterotrophic metabolism

Paik, Sang-Min,Kim, Joonwon,Jin, EonSeon,Jeon, Noo Li Elsevier 2019 Bioresource technology Vol.272 No.-

<P><B>Abstract</B></P> <P>High uptake of malate and efficient distribution of intracellular malate to organelles contributed to biomass increase, reducing maintenance energy. In this study, transgenic <I>Chlamydomonas reinhardtii</I> was developed that stably expresses malate synthase in the chloroplast. The strains under glyoxylate treatment showed 19% more increase in microalgal biomass than wild-type. By RNA analysis, transcript levels of malate dehydrogenase (<I>MDH4</I>) and acetyl-CoA synthetase (<I>ACS3</I>), isocitrate lyase (<I>ICL1</I>) and malate synthase (<I>MAS1</I>), were significantly more expressed (17%, 42%, 24%, and 18% respectively), which was consistent with reported heterotrophic metabolism flux analysis with the objective function maximizing biomass. Photosynthetic F<SUB>v</SUB>/F<SUB>m</SUB> was slightly reduced. A more meticulous analysis is necessary, but, in the transgenic microalgae with malate synthase overexpression, the metabolism is likely to more rely on heterotrophic energy production via TCA cycle and glyoxylate shunt than on photosynthesis, resulting in the increase in microalgal biomass.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Chloroplastic transgenic <I>C. reinhardtii</I> was developed that stably expressed malate synthase. </LI> <LI> This transgenic strain showed a more 19% increase in dry cell weight than wild-type strain. </LI> <LI> Transcripts of <I>MDH4</I>, <I>ACS3</I>, <I>ICL1</I>, and <I>MAS1</I> were increased, and F<SUB>v</SUB>/F<SUB>m</SUB> was decreased. </LI> <LI> Upregulation of heterotrophic metabolism might be involved in biomass increase. </LI> <LI> This could serve as a valuable strain for treating wastewater containing acetate and glyoxylate. </LI> </UL> </P>

Microfluidic platform for single cell analysis under dynamic spatial and temporal stimulation

Song, Jiyoung,Ryu, Hyunryul,Chung, Minhwan,Kim, Youngtaek,Blum, Yannick,Lee, Sung Sik,Pertz, Olivier,Jeon, Noo Li Elsevier 2018 Biosensors & bioelectronics Vol.104 No.-

<P><B>Abstract</B></P> <P>Recent research on cellular responses is shifting from static observations recorded under static stimuli to real-time monitoring in a dynamic environment. Since cells sense and interact with their surrounding microenvironment, an experimental platform where dynamically changing cellular microenvironments should be recreated <I>in vitro</I>. There has been a lack of microfluidic devices to support spatial and temporal stimulations in a simple and robust manner. Here, we describe a microfluidic device that generates dynamic chemical gradients and pulses in both space and time using a single device. This microfluidic device provides at least 12h of continuous stimulations that can be used to observe responses from mammalian cells. Combination of the microfluidic de­vice with live-cell imaging facilitates real-time observation of dynamic cellular response at single cell level. Using stable HEK cells with biosensors, ERK (Extracellular signal-Regulated Kinase) activities were observed un­der the pulsatile and ramping stimulations of EGF (Epidermal Growth Factor). We quantified ERK activation even at extremely low EGF concentration (0.0625µg/ml), which can not be observed using conventional techniques such as western blot. Cytoskeleton re­arrangement of the 3T3 fibroblast (stable transfection with Lifeact-GFP) was compared under abrupt and gradually changing gradient of PDGF.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A long-term live cell monitoring was performed under the spatial and temporal dynamic stimulations. </LI> <LI> Versatile stimulation profiles were generated in a single device without further modification. </LI> <LI> Quantitative observation of the persistent ERK activation with the increasing concentrations of EGF was made initially. </LI> <LI> Prior to the development of our device, ramping down stimulation of certain matters was unable to be achieved. </LI> <LI> Dynamically changing gradients were proposed and can be applied in directed cell migration. </LI> </UL> </P>

Microfluidic perfusion bioreactor for optimization of microalgal lipid productivity

Paik, Sang-Min,Sim, Sang-Jun,Jeon, Noo Li Elsevier 2017 Bioresource technology Vol.233 No.-

<P><B>Abstract</B></P> <P>Nutrient deprivation in a batch process induces microbes to produce secondary metabolites while drastically constraining cellular growth. A microfluidic continuous perfusion system was designed and tested to culture microalgae, <I>Chlamydomonas reinhardtii</I>, under constant nutrient concentration slightly lower than normal condition. When cultured in 7.5%/7.5% of NH<SUB>4</SUB> <SUP>+</SUP>/PO<SUB>4</SUB> <SUP>2</SUP> <SUP>−</SUP>, <I>C. reinhardtii</I> showed a 2.4-fold increase in TAG production with a 3.5-fold increase in biomass compared to level obtained under an only NH<SUB>4</SUB> <SUP>+</SUP> depleted condition. The microfluidic continuous perfusion bioreactor with steady continuous nutrient flow can be used to optimize conditions for enhancing secondary metabolite production and increasing microbial biomass.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Microfluidic perfusion bioreactor is designed for secondary metabolite production. </LI> <LI> Continuous supply of low concentration of nutrient permits microbes to grow at a minimum rate. </LI> <LI> Low nutrient allows same level of metabolite production compared to depleted condition. </LI> <LI> Stable feed of low level of nutrient is an effective way to enhance total TAG yield. </LI> </UL> </P>

Vibration-induced stress priming during seed culture increases microalgal biomass in high shear field-cultivation

Paik, Sang-Min,Jin, EonSeon,Sim, Sang Jun,Jeon, Noo Li Elsevier Applied Science 2018 Bioresource technology Vol.254 No.-

<P><B>Abstract</B></P> <P>Vibrational wave treatment has been used to increase proliferation of microalgae. When directly applied at large scale, however, turbulence can offset positive effects of vibration on microalgae proliferation. Moreover, severe hydrodynamic shear fields in the bioreactor decrease cell viability that detrimentally influence maximum yieldable biomass. In this study, vibration pretreatment (between 10–30 Hz and 0.15–0.45 G) was used to prime the cells for enhanced biomass. When exposed to 10 Hz at 0.15 G for 72 h and inoculated in baffled flasks of large shear fields (0.292 Pa for the average wall shear force (aveWSF) and 184 s<SUP>−1</SUP> for the average shear strain rate (aveSSR)), microalgae showed 27% increase in biomass as well as 39% increase in corresponding amount of heterologous protein (i.e. GFP-3HA). Our results show that stress primed microalgae with vibrations can lead to improved proliferation that results in increased biomass production at industrial scale bioprocesses.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Vibration put microalgal cells into a primed state where to endure severe stresses. </LI> <LI> Primed microalgal cells grew more in harsh shear field-cultivation. </LI> <LI> Stress-priming can contributes to biomass increase and efficient large-scale bioprocess. </LI> <LI> TRP11 was cross-activated linking stresses from mild vibration and harsh shaking. </LI> </UL> </P>

Quantum-dot nanoprobes and AOTF based cross talk eliminated six color imaging of biomolecules in cellular system

Park, Solji,Arumugam, Parthasarathy,Purushothaman, Baskaran,Kim, Sung-Yon,Min, Dal-Hee,Jeon, Noo Li,Song, Joon Myong Elsevier 2017 Analytica chimica acta Vol.985 No.-

<P><B>Abstract</B></P> <P>Primary cell cultures mimic the physiology and genetic makeup of in-vivo tissue of origin, nonetheless, a complication in the derivation and propagation of primary cell culture limits its use in biological research. However, in-vitro models using primary cells might be a complement model to mimic in vivo response. But, conventional techniques such as western blot and PCR employed to study the expression and activation of proteins requires a large number of cells, hence repeated establishment and maintenance of primary culture are unavoidable. Quantum dot (Q-dot) and acousto-optic tunable filters (AOTF) based multiplex imaging system is a viable alternative choice to evaluate multiple signaling molecules by using a small number of cells. Q-dots have broad excitation and narrow emission spectra, which allows to simultaneously excite multiple Q-dots by using single excitation wavelength. The use of AOTF in the fluorescence detection system enables to scan the fluorescence emission intensity of a Q-dot at their central wavelength, this phenomenon effectively avoids spectral overlap among the neighboring Q-dots. When Q-dots are conjugated with antibodies it acts as effective sensing probes. To validate this, the expression pattern of p-JNK-1, p-GSK3β, p-IRS1ser, p-IRS1tyr, p-FOXO1, and PPAR-γ, involved in the insulin resistance were concurrently monitored in adipocyte and HepG2 co-cell culture model. The observed results clearly indicate that PPAR-γ is the critical component in the development of insulin resistance. Moreover, the results proved that developed Q-dot based AOTF imaging methodology is a sensible choice to concurrently monitor multiple signaling molecules with limited cell population.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Quantum dot (Q-dot) and acousto-optic tunable filters (AOTF) based six-colour imaging. </LI> <LI> Expression of PPAR-γ in adipocyte regulates insulin resistance in hepatic (HepG2) cells. </LI> <LI> Aspirin improved insulin sensitivity in adipocytes and HepG2 co-cell culture. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Live Cell Monitoring of Lipid Droplet Formation in Microalgae

Noo Li Jeon,Jae Woo Park,Sang Cheol Na,Youngjun Lee,Sanghee Lee,Seung Bum Park 한국생물공학회 2013 한국생물공학회 학술대회 Vol.2013 No.10

3D Vascularized Vessel Network Platform for Tumor-on-a-Chip

Noo Li Jeon(전누리) 대한기계학회 2020 대한기계학회 춘추학술대회 Vol.2020 No.8

In-Vitro Engineered Perfusable Blood Vessels on a Microfluidic Chip

Noo Li Jeon(전누리) 한국실험동물학회 2013 한국실험동물학회 학술발표대회 논문집 Vol.2013 No.8

“Open-Top” Microfluidic Platform for Vacularized Skin Model

( Noo Li Jeon ) 한국피부장벽학회 2020 한국피부장벽학회지 Vol.22 No.1

This presentation will describe a novel microfluidic platform to co-culture a blood vessel network and epithelial tissues such as skin. The “Open-Top” microfluidic device platform is composed of microchannels with micropores in the ceiling, which provides direct fluid access from reservoir to microchannel. Fluid connections through micropores afford novel advantages, including: i) the long-term culture of large-scale microvessel network, ii) access of different fluids to inner and exterior sides of the microvessel, and iii) co-culturing of the microvessel network with epithelial cell layer. In this study, we have successfully assembled microvessels with 5 mm channel widths. We were also able to mimic capillary bed conditions by co-culturing microvessels with keratinocyte layer. We expect this device to be used as a novel platform for vascularized tissue models.