Liquid-liquid phase separation in organic particles containing one and two organic species: importance of the average O : C

Song, Mijung,Ham, Suhan,Andrews, Ryan J.,You, Yuan,Bertram, Allan K. Copernicus GmbH 2018 Atmospheric Chemistry and Physics Vol.18 No.16

<P>Abstract. Recently, experimental studies have shown that liquid-liquid phase separation (LLPS) can occur in organic particles free of inorganic salts. Most of these studies used organic particles consisting of secondary organic materials generated in environmental chambers. To gain additional insight into LLPS in organic particles free of inorganic salts, we studied LLPS in organic particles consisting of one and two commercially available organic species. For particles containing one organic species, three out of the six particle types investigated underwent LLPS. In these cases, LLPS was observed when the O : C was ≤ 0.44 (but not always) and the relative humidity (RH) was between ∼ 97 % and ∼ 100 %. The mechanism of phase separation was likely nucleation and growth. For particles containing two organic species, 13 out of the 15 particle types investigated underwent LLPS. In these cases, LLPS was observed when the O : C was ≤ 0.58 (but not always) and mostly when the RH was between ∼ 90 % RH and ∼ 100 % RH. The mechanism of phase separation was likely spinodal decomposition. In almost all cases when LLPS was observed (for both one-component and two-component particles), the highest RH at which two liquids was observed was 100±2.0 %, which has important implications for the cloud condensation nuclei (CCN) properties of these particles. These combined results provide additional evidence that LLPS needs to be considered when predicting the CCN properties of organic particles in the atmosphere. </P>

Modeling methane production in anaerobic forward osmosis bioreactor using a modified anaerobic digestion model No. 1

Song, Young-Chae,Kim, Minseok,Shon, Hokyong,Jegatheesan, Veeriah,Kim, Suhan Elsevier 2018 Bioresource Technology Vol.264 No.-

<P><B>Abstract</B></P> <P>Anaerobic membrane bioreactor (AnMBR) using microfiltration (MF) or ultrafiltration (UF) membranes was introduced to enhance poor biomass retention of conventional anaerobic digestion (CAD). Recently, forward osmosis (FO) membrane have been applied to AnMBR, which is called AnFOMBR. FO membrane assures not only high biomass retention but also high removal efficiency for low molecular weight (LMW) matters. Methane production rates in CAD, AnMBR, and AnFOMBR were compared using a modified IWA anaerobic digestion model No. 1 (ADM1) in this work. Accumulation of biomass in AnMBR/AnFOMBR results in enhanced biochemical reaction and gains more methane production. AnFOMBR may experience a significant inhibition by accumulated free ammonia and cations, although concentrated soluble substrates rejected by FO membrane are favorable for more methane production. Rejection rate of inorganic nitrogen is a key parameter to determine the inhibition in methane production of AnFOMBR.</P> <P><B>Highlights</B></P> <P> <UL> <LI> ADM1 is modified to compare the performance of CAD, AnMBR and AnFOMBR. </LI> <LI> Membranes integrated into anaerobic digester can increase SRT. </LI> <LI> Increased SRT in AnMBR enhances methane production up to 0.387 l/gCOD. </LI> <LI> Accumulated free ammonia possibly inhibits methane production in AnFOMBR. </LI> <LI> FO membranes with perfect nitrogen removal are not suitable for AnFOMBR. </LI> </UL> </P>

Effect of Beverage Containing Fermented Akebia quinata Extracts on Alcoholic Hangover

Suhan Jung,Sang Hoon Lee,Young Sun Song,Seo Yeon Lee,So Young Kim,Kwang Suk Ko 한국식품영양과학회 2016 Preventive Nutrition and Food Science Vol.21 No.1

The present study was conducted to investigate the effects of beverages containing fermented Akebia quinata extracts on alcoholic hangover. For this study, 25 healthy young men were recruited. All participants consumed 100 mL of water (placebo), commercial hangover beverage A or B, fermented A. quinata leaf (AQL) or fruit (AQF) extract before alcohol consumption. After 1 h, all participants consumed a bottle of Soju, Korean distilled liquor (360 mL), containing 20% alcohol. Blood was collected at 0 h, 1 h, 3 h, and 5 h after alcohol consumption. The plasma alanine transaminase (ALT) activity was highest in the placebo group. Compared with the control group, the AQL and AQF groups showed decreased ALT activity at 5 h after alcohol consumption. Plasma ethanol concentration was increased after alcohol intake and peaked at 3 h after alcohol consumption. Compared with the control group, the A group showed a higher plasma ethanol concentration at 1 h (P<0.05). At 3 h after alcohol consumption, the AQF group showed the lowest mean plasma ethanol concentration compared to the other groups; however, there were no statistical differences. After 5 h of alcohol consumption, the AQL and AQF groups showed lower plasma ethanol concentrations compared with the B group. The sensory evaluation score for the fermented A. quinata fruit extract was lower than for the commercial hangover beverages. In conclusion, the present intervention study results suggest that fermented A. quinata extracts alleviate alcoholic hangover and reduce plasma ethanol concentrations.

Effect of Beverage Containing Fermented Akebia quinata Extracts on Alcoholic Hangover

Jung, Suhan,Lee, Sang Hoon,Song, Young Sun,Lee, Seo Yeon,Kim, So Young,Ko, Kwang Suk The Korean Society of Food Science and Nutrition 2016 Preventive Nutrition and Food Science Vol.21 No.1

The present study was conducted to investigate the effects of beverages containing fermented Akebia quinata extracts on alcoholic hangover. For this study, 25 healthy young men were recruited. All participants consumed 100 mL of water (placebo), commercial hangover beverage A or B, fermented A. quinata leaf (AQL) or fruit (AQF) extract before alcohol consumption. After 1 h, all participants consumed a bottle of Soju, Korean distilled liquor (360 mL), containing 20% alcohol. Blood was collected at 0 h, 1 h, 3 h, and 5 h after alcohol consumption. The plasma alanine transaminase (ALT) activity was highest in the placebo group. Compared with the control group, the AQL and AQF groups showed decreased ALT activity at 5 h after alcohol consumption. Plasma ethanol concentration was increased after alcohol intake and peaked at 3 h after alcohol consumption. Compared with the control group, the A group showed a higher plasma ethanol concentration at 1 h (P<0.05). At 3 h after alcohol consumption, the AQF group showed the lowest mean plasma ethanol concentration compared to the other groups; however, there were no statistical differences. After 5 h of alcohol consumption, the AQL and AQF groups showed lower plasma ethanol concentrations compared with the B group. The sensory evaluation score for the fermented A. quinata fruit extract was lower than for the commercial hangover beverages. In conclusion, the present intervention study results suggest that fermented A. quinata extracts alleviate alcoholic hangover and reduce plasma ethanol concentrations.

The dynactin subunit DCTN1 controls osteoclastogenesis via the Cdc42/PAK2 pathway

이용덕,김봉준,Suhan Jung,김해민,김민경,권준오,Min-Kyoung Song,이장희,Hong-Hee Kim 생화학분자생물학회 2020 Experimental and molecular medicine Vol.52 No.-

Osteoclasts (OCs), cells specialized for bone resorption, are generated from monocyte/macrophage precursors by a differentiation process governed by RANKL. Here, we show that DCTN1, a key component of the dynactin complex, plays important roles in OC differentiation. The expression of DCTN1 was upregulated by RANKL. The inhibition of DCTN1 expression by gene knockdown suppressed OC formation, bone resorption, and the induction of NFATc1 and c-Fos, critical transcription factors for osteoclastogenesis. More importantly, the activation of Cdc42 by RANKL was inhibited upon DCTN1 silencing. The forced expression of constitutively active Cdc42 restored the OC differentiation of precursors with DCTN1 deletion. In addition, PAK2 was found to be activated by RANKL and to function downstream of Cdc42. The DCTN1-Cdc42 axis also inhibited apoptosis and caspase-3 activation. Furthermore, the antiosteoclastogenic effect of DCTN1 knockdown was verified in an animal model of bone erosion. Intriguingly, DCTN1 overexpression was also detrimental to OC differentiation, suggesting that DCTN1 should be regulated at the appropriate level for effective osteoclastogenesis. Collectively, our results reveal that DCTN1 participates in the activation of Cdc42/PAK2 signaling and the inhibition of apoptosis during osteoclastogenesis.

Barrier protection via Toll-like receptor 2 signaling in porcine intestinal epithelial cells damaged by deoxynivalnol

Gu, Min Jeong,Song, Sun Kwang,Lee, In Kyu,Ko, Seongyeol,Han, Seung Eun,Bae, Suhan,Ji, Sang Yun,Park, Byung-Chul,Song, Ki-Duk,Lee, Hak-Kyo,Han, Seung Hyun,Yun, Cheol-Heui BioMed Central 2016 VETERINARY RESEARCH Vol.47 No.-

<P>Intestinal barrier is the first line of defense inside the body and comprises intercellular tight junction (TJ) proteins that regulate paracellular permeability. Deoxynivalenol (DON), a fungal metabolite often found in the contaminated food of domestic animals, is known to impair intestinal barrier function and may be involved in intestinal inflammation. Unlike in humans and mice, the importance of Toll-like receptor (TLR) 2 expressed in porcine intestinal epithelial cells is largely unclear. Therefore, the aim of the present study was to investigate whether TLR2 stimulation enhances intestinal barrier function and protects against DON exposure. We found that the cells treated with TLR2 ligands decreased the epithelial barrier permeability and enhanced TJ protein expression in intestinal porcine epithelial cells (IPEC-J2). In addition, pretreatment with TLR2 ligand, including Pam3CSK4 (PCSK) and lipoteichoic acid from <I>Bacillus subtilis</I>, prevented DON-induced barrier dysfunction by increasing the expression of TJ proteins via the PI3K-Akt-dependent pathway. It is likely that the DON-disrupted intestinal barrier caused biological changes of immune cells in the lamina propria. Thus, we conducted co-culture of differentiated IPEC-J2 cells in the upper well together with peripheral blood mononuclear cells in the bottom well and found that apical TLR2 stimulation of IPEC-J2 cells could alleviate the reduction in cell survival and proliferation of immune cells. Conclusively, TLR2 signaling on intestinal epithelial cells may enhance intestinal barrier function and prevent DON-induced barrier dysfunction of epithelial cells.</P><P><B>Electronic supplementary material</B></P><P>The online version of this article (doi:10.1186/s13567-016-0309-1) contains supplementary material, which is available to authorized users.</P>

Adaptive Learning of Background Model for Crowd Scenes

Gwang-Gook Lee,Suhan Song,Ja-Young Yoon,Jae-Jun Kim,Whoi-Yul Kim 한국멀티미디어학회 2008 한국멀티미디어학회 국제학술대회 Vol.2008 No.-

Background modeling is widely employed in many surveillance applications. However, previous background modeling methods often fail under crowded circumstances. This paper proposes a background modeling method robust to crowded situation. The proposed method is based on the Gaussian mixture background model proposed by Grimson [6]. Adopting simple frame level analysis, the proposed method controls the learning rate of background model adaptively to the crowded ness of the scene. As a result, the proposed method works similar to the static background model in crowded scenes, but operates as the original Grimson model in normal scenes. Experiment showed that the proposed method increases the accuracy of background subtraction by 14% compared to the original algorithm proposed by Grimson in crowded scenes.

ST5 Positively Regulates Osteoclastogenesis via Src/Syk/calcium Signaling Pathways

Hong-Hee Kim,김민경,김봉준,권준오,Min-Kyoung Song,Suhan Jung,이장희 한국분자세포생물학회 2019 Molecules and cells Vol.42 No.11

For physiological or pathological understanding of bone disease caused by abnormal behavior of osteoclasts (OCs), functional studies of molecules that regulate the generation and action of OCs are required. In a microarray approach, we found the suppression of tumorigenicity 5 (ST5) gene is upregulated by receptor activator of nuclear factor-κB ligand (RANKL), the OC differentiation factor. Although the roles of ST5 in cancer and β-cells have been reported, the function of ST5 in bone cells has not yet been investigated. Knockdown of ST5 by siRNA reduced OC differentiation from primary precursors. Moreover, ST5 downregulation decreased expression of NFATc1, a key transcription factor for osteoclastogenesis. In contrast, overexpression of ST5 resulted in the opposite phenotype of ST5 knockdown. In immunocytochemistry experiments, the ST5 protein is colocalized with Src in RANKL-committed cells. In addition, ST5 enhanced activation of Src and Syk, a Src substrate, in response to RANKL. ST5 reduction caused a decrease in RANKL-evoked calcium oscillation and inhibited translocation of NFATc1 into the nucleus. Taken together, these findings provide the first evidence of ST5 involvement in positive regulation of osteoclastogenesis via Src/Syk/calcium signaling.

ST5 Positively Regulates Osteoclastogenesis via Src/Syk/Calcium Signaling Pathways

Kim, Min Kyung,Kim, Bongjun,Kwon, Jun-Oh,Song, Min-Kyoung,Jung, Suhan,Lee, Zang Hee,Kim, Hong-Hee Korean Society for Molecular and Cellular Biology 2019 Molecules and cells Vol.42 No.11

For physiological or pathological understanding of bone disease caused by abnormal behavior of osteoclasts (OCs), functional studies of molecules that regulate the generation and action of OCs are required. In a microarray approach, we found the suppression of tumorigenicity 5 (ST5) gene is upregulated by receptor activator of nuclear $factor-{\kappa}B$ ligand (RANKL), the OC differentiation factor. Although the roles of ST5 in cancer and ${\beta}-cells$ have been reported, the function of ST5 in bone cells has not yet been investigated. Knockdown of ST5 by siRNA reduced OC differentiation from primary precursors. Moreover, ST5 downregulation decreased expression of NFATc1, a key transcription factor for osteoclastogenesis. In contrast, overexpression of ST5 resulted in the opposite phenotype of ST5 knockdown. In immunocytochemistry experiments, the ST5 protein is colocalized with Src in RANKL-committed cells. In addition, ST5 enhanced activation of Src and Syk, a Src substrate, in response to RANKL. ST5 reduction caused a decrease in RANKL-evoked calcium oscillation and inhibited translocation of NFATc1 into the nucleus. Taken together, these findings provide the first evidence of ST5 involvement in positive regulation of osteoclastogenesis via Src/Syk/calcium signaling.

Graphene as an Interfacial Layer for Improving Cycling Performance of Si Nanowires in Lithium-Ion Batteries

Xia, Fan,Kwon, Sunsang,Lee, Won Woo,Liu, Zhiming,Kim, Suhan,Song, Taeseup,Choi, Kyoung Jin,Paik, Ungyu,Park, Won Il American Chemical Society 2015 NANO LETTERS Vol.15 No.10

<P>Managing interfacial instability is crucial for enhancing cyclability in lithium-ion batteries (LIBs), yet little attention has been devoted to this issue until recently. Here, we introduce graphene as an interfacial layer between the current collector and the anode composed of Si nanowires (SiNWs) to improve the cycling capability of LIBs. The atomically thin graphene lessened the stress accumulated by volumetric mismatch and inhibited interfacial reactions that would accelerate the fatigue of Si anodes. By simply incorporating graphene at the interface, we demonstrated significantly enhanced cycling stability for SiNW-based LIB anodes, with retentions of more than 2400 mAh/g specific charge capacity over 200 cycles, 2.7 times that of SiNWs on a bare current collector.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2015/nalefd.2015.15.issue-10/acs.nanolett.5b02482/production/images/medium/nl-2015-02482j_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nl5b02482'>ACS Electronic Supporting Info</A></P>