Hollow Cobalt Selenide Microspheres: Synthesis and Application as Anode Materials for Na-Ion Batteries

Ko, You Na,Choi, Seung Ho,Kang, Yun Chan American Chemical Society 2016 ACS APPLIED MATERIALS & INTERFACES Vol.8 No.10

<P>The electrochemical properties of hollow cobalt oxide and cobalt selenide microspheres are studied for the first time as anode materials for Na-ion batteries. Hollow cobalt oxide microspheres prepared by one-pot spray pyrolysis are transformed into hollow cobalt selenide microspheres by a simple selenization process using hydrogen selenide gas. Ultrafine nanocrystals of Co3O4 microspheres are preserved in the cobalt selenide microspheres selenized at 300 degrees C. The initial discharge capacities for the Co3O4 and Cobalt selenide microspheres selenized at 300 and 400 degrees C are 727, 595, and 586 mA h g(-1), respectively, at a current density of 500 mA g(-1). The discharge capacities after 40 cycles for the same samples are 348, 467, and 251 mA h g(-1), respectively, and their capacity retentions measured from the second cycle onward are 66, 91, and 50%; respectively. The hollow cobalt selenide microspheres have better rate performances than the hollow cobalt oxide microspheres.</P>

The Comparison of Clinical Outcomes between Inactive Chronic Hepatitis B and HBeAg Negative Hepatitis B with Virologic Response

( Seong Kyun Na ),( Byung-cheol Song ),( Eun Kwang Choi ) 대한간학회 2018 춘·추계 학술대회 (KASL) Vol.2018 No.1

Aims: Nucleos(t)ide analogues (NA) suppress HCC development in chronic hepatitis B (CHB) patients. This study is aimed to compare incidence of hepatocellular carcinoma and survival between inactive chronic hepatitis B (CHB) patients and HBeAg(-) CHB patients with virologic response. Methods: We retrospectively analyzed NA-naïve inactive CHB patients (n=80) and HBeAg(-) CHB patients on entecavir with virologic response (VR, DNA<2000 IU/mL) (n=72) at Jeju National University Hopital in Jeju, Korea, between March 2007 and December 2010. Decompensated liver cirrhosis patients were excluded. Results: Median follow-up duration was 8.1 years (interquartile range[IQR] 7.0 - 9.0). Age, sex distribution were not different between two groups, however, patients with liver cirrhosis was higher in HBeAg(-) CHB group (8.8% versus 30.6%, P=0.001). During the follow up, one HCC (1.3%) and 10 HCCs (13.9%) were developed, in inactive group and HBeAg(-) CHB group, respectively. Estimated 10-year HCC incidence rates were 1.5% in inactive group and 25.4% in HBeAg(-) CHB group (P<0.001). Progression to decompensation was comparable (no event in inactive group, one hepatic encephalopathy in HBeAg(-) CHB group, P=0.278). Liver-related death was also similar (no death in inactive group, one death in HBeAg(-) CHB group, P=0.278). In multivariable analysis, HBeAg(-) CHB (adjusted hazard ratio[aHR] 10.17 (95% confidence interval[CI] 1.20-86.29), P=0.034) and liver cirrhosis (aHR 11.02 (95% CI 2.61-46.63), P=0.001) were significant risk factors for HCC. Conclusions: Between inactive CHB patients and HBeAg(-) CHB patients on entecavir with VR, overall survival was comparable. However, HCC incidence was significantly higher in HBeAg(-) CHB patients with VR.

논에서 우분액비 시용이 총체보리 및 이탈리안 라이그라스의 생산성과 사료가치 및 환경오염에 미치는 영향

최기춘,나상필,정민웅,임영철,박형수,김종근,김원호,김맹중,최기준,김명화,이상락,김다혜,육완방,Choi, Ki-Choon,Na, Sang-Pil,Jung, Min-Woong,Lim, Young-Chul,Park, Hyung-Su,Kim, Jong-Geun,Kim, Won-Ho,Kim, Maeng-Jung,Choi, Gi-Jun,Kim, Myeong-Hwa,L 한국축산환경학회 2012 축산시설환경학회지 Vol.18 No.2

본 연구는 논에서 조사료 생산을 위한 작부형태별 우분액비의 시용효과를 규명하기 위하여 총체 벼 재배 후 우분액비 시용에 따른 총체보리 및 IRG의 생산성, 사료가치, 토양성분 및 용탈수중의 무기물 농도를 조사하였다. 본 연구는 2006년 5월부터 2009년 4월까지 3년 동안 전라북도 김제군 백산면 시험포장에서 완전임의배치 3반복으로 수행되었다. 총체보리의 2년간 평균수량은 7,520 kg/ha, 그리고 IRG는 평균 10,320 kg/ha으로 IRG가 총체보리 보다 현저하게 높은 수량을 보였다 (p<0.05). 이탈리안 라이그라스는 1번초가 2번초 보다 약 2배 이상의 수량을 보였다. IRG의 조단백질 함량은 총체보리보다 높았고 NDF, ADF 및 TDN 함량은 작물간에 큰 차이는 보이지 않았다. 경작형태별 우분액비 시용에 따른 토양내 pH, $P_2O_5$, T-N, OM 농도는 시험전에 비해 시험종료 후에 현저하게 증가하는 경향을 나타냈다 (p<0.05). 경작형태별 우분액비 시용에 따른 토양내 Ca, Na, Mg 및 K 농도는 시험전에 비해 시험종료 후에 현저하게 증가하는 경향을 나타냈다 (P<0.05). 경작형태별 우분액비 시용에 따른 용탈수중 $NH_4$-N, $NO_3$-N, $PO_4$-P, Cl, Ca, K, Mg, Na의 농도는 경작형태에 따른 확실한 차이를 보여주지 않았다. 따라서 논에서 우분액비를 이용하여 동계작물을 재배할 경우에는 수량도 중요하지만 환경적인 부분도 고려하여 우분액비를 이용해야 한다. This study was conducted to investigate the effects of cattle slurry on productivity of whole crop barley and Italian ryegrass and environmental pollution in paddy land. Cropping systems used in this study were consisted of two designs, such as whole crop barley applied with cattle slurry (WCB) and Italian ryegrass applied with cattle slurry (IRG). The field experiments were conducted on the clay loam at Backsanmyun, Kimje, Chunlabukdo province in Korea for three years (May 2006 to Apr. 2009). This study was arranged in completely randomized design with three replicates. The yields of WCB and IRG were 7,520 kg/ha and 10,320 kg/ha, respectively. The yields of IRG significantly increased as compared with that of WCB (p<0.05). The yield of Italian ryegrass in 1st cutting time was about 2-fold higher than that of 2nd cutting time. The contents of crude protein of IRG were higher than that of WCB. However, the contents of NDF, ADF and TDN were no difference between WCB and IRG treatments. The pH, and contents of T-N, $P_2O_5$ and organic matter (OM) in soil samples collected at the end of the experiment increased as compared with those at the beginning of the experiment (p<0.05). After the end of experiment, the concentrations of CEC (Ca, Na, Mg and K) in soil samples collected at the end of the experiment were remarkably higher than those at the beginning of the experiment (p<0.05). The concentrations of $NH_4$-N, $NO_3$-N, $PO_4$-P, Cl, Ca, K, Mg and Na in leaching water in paddy land cultivated with WCB and IRG were no difference between WCB and IRG treatments.

Efficacy of Long-Term Tenofovir-Based Therapy in Chronic Hepatitis B Patients with Previous Nucleos(t)ide Analogues Treatment Experience

( Na Eun Lee ),( Hong Seon Son ),( Sung Hoon Choi ),( Chang Hun Lee ),( Seung Young Seo ),( Seong Hun Kim ),( Sang Wook Kim ),( Seung Ok Lee ),( Soo Teik Lee ),( Dae Ghon Kim ),( In Hee Kim ) 대한간학회 2017 춘·추계 학술대회 (KASL) Vol.2017 No.1

Aims: Tenofovir disoproxil fumarate (TDF) is considered as the preferred treatment option for chronic hepatitis B (CHB) patients with treatment failure or resistance to prior nucleos(t)ide analogues (NAs) treatment. We investigated the efficacy of long-term TDF-based therapy in CHB patients with previous NAs-experience. Methods: This study included total 251 patients who had previous history of NAs therapy and were treated with TDF mono (n=173) or TDF combined with other NA (n=78) from August 2012 to March 2017. Virologic response (VR) was defined as undetectable serum HBV DNA by PCR (<20 IU/mL). Results: Mean age of patients was 49.3 years, median duration of TDF therapy was 27.2 months, 75.7% were HBeAg-positive, and median HBV DNA was 3.7 log10IU/mL. The cumulative rates of VR were 188/244 (77.0%), 180/211 (85.3%), and 146/161 (90.7%) at 12, 24, and 36 months, respectively. Multivariate analysis showed that body mass index (OR 0.77, 95% CI 0.61-0.95, p=0.0189) and duration of TDF therapy (OR 1.09, 95% CI 1.02-1.18, p=0.0221) was significantly associated with VR. TDF monotherapy, HBeAg-positivity, platelet count, serum albumin was associated with VR in the univariate analysis, but not significant in the multivariate analysis. In relation to renal safety, patients showed renal impairment (7, 3.0%), mild hypophosphatemia (15, 7.2%), severe hypophosphatemia (1, 0.4%). Conclusions: Long-term TDF-based therapy demonstrated highly effective in viral suppression and relatively favorable renal safety in CHB patients with previous NA-experience. The body mass index and duration of TDF therapy was independent factors associated with VR.

Extended Culture of Bone Marrow with Granulocyte Macrophage-Colony Stimulating Factor Generates Immunosuppressive Cells

Na, Hye Young,Sohn, Moah,Ryu, Seul Hye,Choi, Wanho,In, Hyunju,Shin, Hyun Soo,Park, Chae Gyu 한국조명·전기설비학회 2018 한국조명·전기설비학회 학술대회논문집 Vol. No.

<P>Bone marrow-derived dendritic cells (BM-DCs) are generated from bone marrow (BM) cells cultured with granulocyte macrophage-colony stimulating factor (GM-CSF) for a week. In this study we investigated the effect of duration on the BM culture with GM-CSF. Within several months, the cells in the BM culture gradually expressed homogeneous levels of CD11c and major histocompatibility complex II on surface, and they became unable to stimulate allogeneic naïve T cells in mixed lymphocyte reaction (MLR). In addition, when the BM culture were sustained for 32 wk or longer, the BM cells acquired ability to suppress the proliferation of allogeneic T cells in MLR as well as the response of ovalbumin-specific OT-I transgenic T cells in antigen-dependent manner. We found that, except for programmed death-ligand 1, most cell surface molecules were expressed lower in the BM cells cultured with GM-CSF for the extended duration. These results indicate that BM cells in the extended culture with GM-CSF undergo 2 distinct steps of functional change; first, they lose the immunostimulatory capacity; and next, they gain the immunosuppressive ability.</P>

Cyclic diquaternary ammoniums for nanocrystalline BEA, MTW and MFI zeolites with intercrystalline mesoporosity

Na, Kyungsu,Choi, Minkee,Ryoo, Ryong Royal Society of Chemistry 2009 Journal of materials chemistry Vol.19 No.37

<P>3,10-Diazoniabicyclo[10.2.2]hexadeca-12,14,15-triene-3,3,10,10-tetramethyl-dichloride is an effective structure-directing agent for BEA zeolite under a high concentration of Na<SUP>+</SUP>. The pseudomorphic crystallization process led to nanocrystalline BEA particles possessing a large volume of intercrystalline mesopores. The synthesis of nanocrystalline zeolite has been extended to other cyclic diammonium compounds that can generate BEA, MTW and MFI zeolite structures. Phase diagrams for these nanocrystalline zeolites have been constructed using sodium silicate as a silica source. The nanocrystalline morphologies and intercrystalline mesoporosity have been characterized by electron microscopy and N<SUB>2</SUB> adsorption. The result indicates that the pseudomorphic crystallization process is limited to BEA, and not MTW or MFI despite their nanocrystalline morphologies.</P> <P>Graphic Abstract</P><P>Cyclic diquaternary ammonium compounds turned out to be effective as structure-directing agents for nanocrystalline BEA, MTW and MFI zeolites with high mesoporosity. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b909792a'> </P>

Microbial Differentiation on Chemical Properties of Paddy Soils in Reclaimed Tidal Lands at Western-coast Area of Korea

Mi-Na Park,Kwang-Min Yang,Jin-Hee Ryu,Tongmin Sa,Joon-Ho Choi 한국토양비료학회 2016 한국토양비료학회지 Vol.49 No.4

The scientific information on the microbial differentiation according to the changes in chemical properties of paddy soil in reclaimed tidal lands is not enough to understand the reclamation processes. The changes in microflora based on the chemical properties of paddy soils at the same sites of reclaimed tidal lands (21 samples from Nampo, Ewon, Sukmoon and Shihwa sites) were investigated in 2013 and 2015. In general, organic matter in paddy soils increased whereas pH decreased with the reclamation time. The electrical conductivities (EC) of soil samples were closely related to the exchangeable Na+. With an increases in EC of paddy soils from 0.39 to 48.9 dS m-1, the ratios (%) of halotolerant and halophilic bacteria to mesophilic bacteria proportionally increased from 0.2% to 102,000%. The population of halotolerant and halophilic bacteria in total microflora was also differentiated with the changes in EC of the same sites from reclaimed tidal soils within 2 years. The population of mesophilic bacteria decreased with an increase in EC above 5 dS m-1. The microflora including halotolerant and halophilic bacteria could be a candidate as a biological parameter in evaluating the reclamation processes in addition to the chemical index of EC.

Gintonin facilitates catecholamine secretion from the perfused adrenal medulla

Seung-Yeol Na,Ki-Hwan Kim,Mi-Sung Choi,Kang-Su Ha,Dong-Yoon Lim 대한생리학회-대한약리학회 2016 The Korean Journal of Physiology & Pharmacology Vol.20 No.6

The present study was designed to investigate the characteristics of gintonin, one of components isolated from Korean Ginseng on secretion of catecholamines (CA) from the isolated perfused model of rat adrenal gland and to clarify its mechanism of action. Gintonin (1 to 30 μg/ml), perfused into an adrenal vein, markedly increased the CA secretion from the perfused rat adrenal medulla in a dose-dependent fashion. The gintonin-evoked CA secretion was greatly inhibited in the presence of chlorisondamine (1 μM, an autonomic ganglionic bloker), pirenzepine (2 μM, a muscarinic M₁ receptor antagonist), Ki14625 (10 μM, an LPA_1/3 receptor antagonist), amiloride (1 mM, an inhibitor of Na⁺/Ca²⁺ exchanger), a nicardipine (1 μM, a voltage-dependent Ca²⁺ channel blocker), TMB-8 (1 μM, an intracellular Ca²⁺antagonist), and perfusion of Ca²⁺-free Krebs solution with 5mM EGTA (a Ca²⁺chelater), while was not affected by sodium nitroprusside (100 μM, a nitrosovasodialtor). Interestingly, LPA (0.3~3 μM, an LPA receptor agonist) also dose-dependently enhanced the CA secretion from the adrenal medulla, but this facilitatory effect of LPA was greatly inhibited in the presence of Ki 14625 (10 μM). Moreover, acetylcholine (AC)-evoked CA secretion was greatly potentiated during the perfusion of gintonin (3 μg/ml). Taken together, these results demonstrate the first evidence that gintonin increases the CA secretion from the perfused rat adrenal medulla in a dose-dependent fashion. This facilitatory effect of gintonin seems to be associated with activation of LPA- and cholinergic-receptors, which are relevant to the cytoplasmic Ca²⁺ increase by stimulation of the Ca²⁺ influx as well as by the inhibition of Ca²⁺ uptake into the cytoplasmic Ca²⁺ stores, without the increased nitric oxide (NO). Based on these results, it is thought that gintonin, one of ginseng components, can elevate the CA secretion from adrenal medulla by regulating the Ca²⁺ mobilization for exocytosis, suggesting facilitation of cardiovascular system. Also, these findings show that gintonin might be at least one of ginseng-induced hypertensive components.

Chitosan/oleamide Nanofluid for Enhancing Gas Utilization Efficiency in C1-gas Bioconversion

Eungsu KANG,Hyunsuk CHOI,Ji Yeong LEE,Min-sik KIM,Jeong Geol NA,Yoo Seong CHOI 한국생물공학회 2021 한국생물공학회 학술대회 Vol.2021 No.10

Microbial biotransformation using C1-gases (CH₄, CO) is a notable technique for sustainable, carbon-neutral chemical and fuel production. However, the low mass transfer coefficient (KLa) of C1-gases in biological processes has hampered the efficient production of value-added materials, despite efficient, nonnative strains having been recently developed. Here, we constructed a nanofluid material mainly composed of chitosan and oleamide (CS/OA), which was stably suspended with a particle size of 120.7 ± 39.0 ㎚ in aqueous culture media below pH 7.5. The kLa value was enhanced more than 1.5-fold with a reduction of surface tension even in the 0.0001 % (w/v) CS/OA nanofluid. In addition, when the nanofluid was applied into media for seed-cultivation of three C1-gas utilizing strains such as Methylomonas sp. DH-1, M. trichosporium OB3b, and Thermococcus onnurineus NA1 156T, the CS/OA nanoparticles attached to the cell surface, leading to a morphological change in the cell surface at extended lag-phase, and enhanced the specific cell growth rates (μmax), gas utilization efficiency in log-phase. Remarkably, the adapted strains from the seed culture using the CS/OA nanofluid media also had enhanced μmax in a subsequent subculture and the main culture using conventional culture media, resulting in higher C1 gas consumption, cell growth, and metabolite production such as formate and succinate. These results showed that the CS/OA nanofluid could be an effective medium component to enhance the gas utilization efficiency in C1-gas microbial bioconversion.Microbial biotransformation using C1-gases (CH₄, CO) is a notable technique for sustainable, carbon-neutral chemical and fuel production. However, the low mass transfer coefficient (KLa) of C1-gases in biological processes has hampered the efficient production of value-added materials, despite efficient, nonnative strains having been recently developed. Here, we constructed a nanofluid material mainly composed of chitosan and oleamide (CS/OA), which was stably suspended with a particle size of 120.7 ± 39.0 ㎚ in aqueous culture media below pH 7.5. The kLa value was enhanced more than 1.5-fold with a reduction of surface tension even in the 0.0001 % (w/v) CS/OA nanofluid. In addition, when the nanofluid was applied into media for seed-cultivation of three C1-gas utilizing strains such as Methylomonas sp. DH-1, M. trichosporium OB3b, and Thermococcus onnurineus NA1 156T, the CS/OA nanoparticles attached to the cell surface, leading to a morphological change in the cell surface at extended lag-phase, and enhanced the specific cell growth rates (μmax), gas utilization efficiency in log-phase. Remarkably, the adapted strains from the seed culture using the CS/OA nanofluid media also had enhanced μmax in a subsequent subculture and the main culture using conventional culture media, resulting in higher C1 gas consumption, cell growth, and metabolite production such as formate and succinate. These results showed that the CS/OA nanofluid could be an effective medium component to enhance the gas utilization efficiency in C1-gas microbial bioconversion.

품종별 무화과의 영양성분 비교

나환식 ( Hwan Sik Na ),김진영 ( Jin Young Kim ),박학재 ( Hak Jae Park ),최경철 ( Gyeong Cheol Choi ),양수인 ( Soo In Yang ),이지헌 ( Ji Heon Lee ) 한국식품저장유통학회(구 한국농산물저장유통학회) 2013 한국식품저장유통학회지 Vol.20 No.3

국내에서 주로 재배되는 무화과 품종인 도후인(Dauphine)2종, 봉래시(Horaish)2종, 바나네(Banane) 1종을 대상으로 이화학적 특성을 분석한 결과, 무화과의 수분은 85.37~87.28%, 회분 0.38~0.43%, 조지방 0.20~0.26%, 조단백질 0.39~0.81%로 품종별 차이는 보이지 않았으며 조섬유는 바나네가 7.55±0.13%로 다른 품종 5.12~7.60%에 비해 다소 높은 결과를 보였다. 무기성분 함량은 모든 품종에서 K>Ca>Mg>Na순으로 나타났으며 전체 함량의 경우 도후인 품종이 타 품종에 비해 조금 높은 결과를 보였다. 바나네 품종과 봉래시 품종의 총 유리아미노산 조성은 glutamic acid>proline>aspartic acid 순으로 높은 분포를 보였으며, 전체 함량의 51.68~58.71%를 차지하고 있으며, 도후인 품종의 경우 glutamic acid>aspartic acid>alanine이 전체의 약 50%를 차지하고 있었다. 또한 기억력 감퇴 예방 등 학습 능력에 도움을 주는 기능성 물질인 γ-aminobutyric acid(GABA) 함량은 바나네에서 26.69mg/100g으로 상당히 높은 함량을 보였다. 총 폴리페놀 함량은 도후인이 198.91~261.64mg/kg, 봉래시 품종이 169.90~174.33mg/kg, 바나네 품종이 211.07mg/kg으로 나타났으며 총 플라보노이드 함량은 바나네(84.95mg/kg), 도후인(60.47~68.71mg/kg), 봉래시(44.12~44.60mg/kg)순으로 바나네가 가장 높았으며 품종간의 차이를 보였따. 플라보노이드성분 중 quercetin과 kaempferol은 각각 2.40~3.54mg/kg, 1.09~1.16mg/kg으로 분석되었다. In this study, the proximate compositions, minerals, free amino acids, total polyphenol and flavonoids of figs were analyzed according to their cultivars. The proximate compositions showed moisture at 85.37~87.28%, crude ash at 0.38~0.43%, crude lipid at 0.20~0.26%, crude protein at 0.39~0.81%, carbohydrate at 11.23~13.66% and crude fiber at 5.12~7.55% (dry base). The amounts of the following minerals in the figs were highest, in this order: K > Ca > Mg > Na. The total polyphenol contents were highest in this order: Dauphine (198.91~261.64mg/kg), Banane (211.07 mg/kg) and Horaish (169.90~174.33 mg/kg). The total flavonoid contents were highest in this order. Banane (84.52 mg/kg) > Dauphine (60.47~68.71 mg/kg) > Horaish (44.12~44.60mg/kg). The quercetin contents were highest in this order. Dauphine, 2.40~3.54 mg/kg; Banane, 3.54 mg/kg; and Horaish, 2.40~2.75 mg/kg; but the flavonoid contents were lowest in this order. Dauphine, 1.11~1.16 mg/kg; Banane, 1.14 mg/kg; and Horaish, 1.09~1.11 mg/kg. The free amino acid content of the figs was 199.70~328.77 mg/100g; their essential free amino acid contents, 46.45~67.46 mg/100 g; and their GABA (γ-aminobutyric acid) contents, 13.57~26.69 mg/100 g.