Novel Polyhydroxybutyrate-Degrading Activity of the Microbulbifer Genus as Confirmed by Microbulbifer sp. SOL03 from the Marine Environment

( Sol Lee Park ),( Jang Yeon Cho ),( Su Hyun Kim ),( Hong-ju Lee ),( Sang Hyun Kim ),( Min Ju Suh ),( Sion Ham ),( Shashi Kant Bhatia ),( Ranjit Gurav ),( See-hyoung Park ),( Kyungmoon Park ),( Yun-go 한국미생물 · 생명공학회 2022 Journal of microbiology and biotechnology Vol.32 No.1

Ever since bioplastics were globally introduced to a wide range of industries, the disposal of used products made with bioplastics has become an issue inseparable from their application. Unlike petroleum-based plastics, bioplastics can be completely decomposed into water and carbon dioxide by microorganisms in a relatively short time, which is an advantage. However, there is little information on the specific degraders and accelerating factors for biodegradation. To elucidate a new strain for biodegrading poly-3-hydroxybutyrate (PHB), we screened out one PHB-degrading bacterium, Microbulbifer sp. SOL03, which is the first reported strain from the Microbulbifer genus to show PHB degradation activity, although Microbulbifer species are known to be complex carbohydrate degraders found in high-salt environments. In this study, we evaluated its biodegradability using solid- and liquid-based methods in addition to examining the changes in physical properties throughout the biodegradation process. Furthermore, we established the optimal conditions for biodegradation with respect to temperature, salt concentration, and additional carbon and nitrogen sources; accordingly, a temperature of 37℃ with the addition of 3% NaCl without additional carbon sources, was determined to be optimal. In summary, we found that Microbulbifer sp. SOL03 showed a PHB degradation yield of almost 97% after 10 days. To the best of our knowledge, this is the first study to investigate the potent bioplastic degradation activity of Microbulbifer sp., and we believe that it can contribute to the development of bioplastics from application to disposal.

Adipic Acid Assisted Sol-Gel Synthesis of Li_1+x(Mn_0.4Ni_0.4Fe_0.2)_1-xO₂ (0 < x < 0.3) as Cathode Materials for Lithium Ion Batteries

Karthikeyan, Kaliyappan,Amaresh, Samuthirapandian,Son, Ju-Nam,Kim, Shin-Ho,Kim, Min-Chul,Kim, Kwang-Jin,Lee, Sol-Nip,Lee, Yun-Sung Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.1

Layered $Li_{1+x}(Mn_{0.4}Ni_{0.4}Fe_{0.2})_{1-x}O_2$ (0 < x < 0.3) solid solutions were synthesized using solgel method with adipic acid as chelating agent. Structural and electrochemical properties of the prepared powders were examined by means of X-ray diffraction, Scanning electron microscopy and galvanostatic charge/discharge cycling. All powders had a phase-pure layered structure with $R\bar{3}m$ space group. The morphological studies confirmed that the size of the particles increased at higher x content. The charge-discharge profiles of the solid solution against lithium using 1 M $LiPF_6$ in EC/DMC as electrolyte revealed that the discharge capacity increases with increasing lithium content at the 3a sites. Among the cells, $Li_{1.2}(Mn_{0.32}Ni_{0.32}Fe_{0.16})O_2$ (x = 0.2)/$Li^+$ exhibits a good electrochemical property with maximum initial capacity of 160 $mAhg^{-1}$ between 2-4.5 V at 0.1 $mAcm^{-2}$ current density and the capacity retention after 25 cycles was 92%. Whereas, the cell fabricated with x = 0.3 sample showed continuous capacity fading due to the formation of spinel like structure during the subsequent cycling. The preparation of solid solutions based on $LiNiO_2-LiFeO_2-Li_2MnO_3$ has improved the properties of its end members.

Adipic Acid Assisted Sol-Gel Synthesis of Li1+x(Mn0.4Ni0.4Fe0.2)1-xO2 (0 < x < 0.3) as Cathode Materials for Lithium Ion Batteries

Kaliyappan Karthikeyan,Samuthirapandian Amaresh,Ju-Nam Son,Shin-Ho Kim,Min-Chul Kim,김광진,이윤성,Sol-Nip Lee 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.1

Layered Li1+x(Mn0.4Ni0.4Fe0.2)1-xO2 (0 < x < 0.3) solid solutions were synthesized using solgel method with adipic acid as chelating agent. Structural and electrochemical properties of the prepared powders were examined by means of X-ray diffraction, Scanning electron microscopy and galvanostatic charge/discharge cycling. All powders had a phase-pure layered structure with R3m space group. The morphological studies confirmed that the size of the particles increased at higher x content. The charge-discharge profiles of the solid solution against lithium using 1 M LiPF6 in EC/DMC as electrolyte revealed that the discharge capacity increases with increasing lithium content at the 3a sites. Among the cells, Li1.2(Mn0.32Ni0.32Fe0.16)O2 (x = 0.2)/ Li+ exhibits a good electrochemical property with maximum initial capacity of 160 mAhg−1 between 2-4.5 V at 0.1 mAcm−2 current density and the capacity retention after 25 cycles was 92%. Whereas, the cell fabricated with x = 0.3 sample showed continuous capacity fading due to the formation of spinel like structure during the subsequent cycling. The preparation of solid solutions based on LiNiO2-LiFeO2-Li2MnO3 has improved the properties of its end members.

Proton-irradiated Pb(Zr_0.52Ti_0.48)O₃ thick films for flexible non-volatile memory applications

Lee, Tae Kwon,Kong, Dae Sol,Jin, Da Woon,Yun, Shinhee,Yang, Chan-Ho,Jung, Jong Hoon ELSEVIER 2019 Current Applied Physics Vol.19 No.6

<P><B>Abstract</B></P> <P>We investigated the ferroelectricity in proton-irradiated flexible Pb(Zr<SUB>0.52</SUB>Ti<SUB>0.48</SUB>)O<SUB>3</SUB> (PZT) thick films and their non-volatile memory characteristics. The Ni-Cr metal foil substrate allowed high-quality polycrystalline PZT films with flexible functionality to be fabricated using conventional sol-gel and high-temperature annealing methods. The 10-MeV proton-irradiated PZT film exhibited an almost square polarization−electric field hysteresis curve with saturated (<I>P</I> <SUB>s</SUB>) and remnant (<I>P</I> <SUB> <I>r</I> </SUB>) polarizations of 18.9 and 17.0 μC/cm<SUP>2</SUP>, respectively; which are slightly lower than as-grown PZT with <I>P</I> <SUB>s</SUB> = 28.7 μC/cm<SUP>2</SUP> and <I>P</I> <SUB> <I>r</I> </SUB> = 24.3 μC/cm<SUP>2</SUP>. The <I>P</I> <SUB> <I>r</I> </SUB> did not decrease even after 1000 cycles of continuous bending and unbending at a bending radius of 2.14 mm and decreased slightly to ∼80% of its initial value after 10<SUP>5</SUP> s. Although the <I>P</I> <SUB> <I>r</I> </SUB> decreased to ∼55% after 10<SUP>10</SUP> cycles, the electric polarization remained switchable under positive and negative electric fields. These characteristics suggest that the flexible PZT films could be utilized in non-volatile memory device applications in environments with high doses of proton irradiation, such as those in aeronautics and nuclear power plants.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Sol-gel growth of flexible PZT thick films on a Ni-Cr metal foil substrate. </LI> <LI> Large saturated and remnant electric polarization in proton-irradiated films. </LI> <LI> Mechanical stability, long retention time, and high fatigue resistance even after the high energy proton-irradiation. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

다량의 골양물질을 형성한 중심성 거대세포육아종의 영상진단

이설미,허민석,이삼선,최순철,박태원 대한구강악안면방사선학회 2000 Imaging Science in Dentistry Vol.30 No.2

A 19-year-old man was referred to Seoul National University Dental Hospital for evaluation of a large painless swelling of the left mandibular angle area in August, 1999. The growth had been first noted 6 years ago. He had visited other hospital in 1997. In spite of the treatment given at the hospital, the mass continued to grow rapidly. Conventional radiographs in 1999 showed an expansile, lobulated, and destructive lesion of the left mandibular body. CT scan demonstrated an expansile mass with a corticated margin. Bony septa were seen within the lesion. Internal calcification noted on the bone-setting CT image, and corresponded to the hypointense area in T1-weighted MRI image. MRI clearly delineated the extent of the lesion which had heterogenous intermediate signal intensity in T1-weighted images and heterogenous hyperintense signal intensity in T2-weighted images. The lesion was well-enhanced. Histopathologically, the lesion was well demarcated. Multinucleated giant cells were presented in a fibrous background, demonstrating a storiform pattern. Areas of osteoid rimmed by a few osteoblasts were scattered throughout the lesion. Inflammatory cells, blood vessels, and hemosiderin deposition were also shown. CGCG may show lots of internal calcification foci on the CT, and varied signal intensity in MRI. More cases will be needed to understand the features of the CT & MR fonding of CGCG. (Korean J Oral Maxillofac Radiol 2000 ; 30 : 127-131)

미얀마 건조지 토지피복 변화와 식생온도조건지수간의 관계분석

최솔이 ( Sol E Choi ),이우균 ( Woo Kyun Lee2 ),( Hangnan Yu ),강호덕 ( Ho Duck Kang ),김용석 ( Yong Suk Kim ) 한국지리정보학회 2014 한국지리정보학회지 Vol.17 No.2

본 연구에서는 미얀마 내 Mandalay, Magway 지역에 대해 Landsat 4-5 TM 위성영상을 이 용하여 토지피복 변화와 식생온도조건지수(Vegetation Temperature Condition Index; VTCI)의 관계를 분석함으로써, 미얀마 토지피복 변화와 건조 정도의 관계를 밝히고자 하였다. 토지피복 변 화를 분석한 결과, 연구 대상 지역에서 산림은 감소하는 것으로 나타난 반면, 주거지와 농경지의 면적은 증가하였다. VTCI 분석을 수행한 결과, (a)지역에서는 매우 건조한 지역의 면적이 점차 감소하고, 건조한 지역 및 보통, 습윤한 지역의 면적이 증가하여 건조의 정도가 다소 감소되는 것 으로 나타났다. (b)지역 또한 매우 건조한 지역의 면적이 증가하여 건조 정도가 심각해지는 것을 파악할 수 있었다. VTCI와 토지피복 변화의 관계 분석결과는 두 지역의 매우 건조한 지역에서 산 림 및 주거지의 농경지로의 변화 비율이 비교적 높게 나타나고, 변화된 지역의 VTCI 평균이 감소 하여 토지피복의 변화와 건조 정도의 변화의 관련성을 찾을 수 있었으며, 건조지역이 점차 증가하 고 있음을 확인하였다. Condition Index(VTCI) using Landsat 4-5 TM satellite images in Central Dry Zones of Myanmar. As a result of land cover classifications, while vegetation areas gradually decrease, residential area and cropland were increased. VTCI analysis shows that region (a) showed a gradual decrease in the area of severely arid, and increase in the area of moderate dry and wet, which sums up to a slight decrease in aridity. Region (b) also showed to increase in dry areas and severe aridity. The result of relational analysis between VTCI and land cover change showed high ratio of land cover change, from severe arid area to forest and residential farmland. The average VTCI decreased in the changed land covers, which indicates the relationship between aridity and land cover change and a gradual increase in the arid area was identified.

Lead-free (K,Na)NbO3 Thick Films for Flexible Non-volatile Memory Applications

Kwak Yeong Min,Lee Tae Kwon,Kong Dae Sol,Ko Young Joon,Jeong Dong Geun,Jung Jong Hoon 한국물리학회 2020 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.77 No.9

We report the sol-gel fabrication and electrical characterization of flexible (K,Na)NbO3 (KNN) thick films. Muscovite mica allows the growth of high-quality polycrystalline KNN thick films with flexible functionality. Because of the trade-off between increase of grain-size and volatilization of alkaline ions, the electrical polarization is optimized at certain temperature of 720 °C. The remnant and saturation polarization of flexible KNN films were recorded to Pr=10.3 μC/cm2 and Ps = 23.3 μC/cm2, respectively, which are quite close to those of rigid films with the same chemical compositions. The KNN thick films are bendable even up to bending radius of R = 3.1 mm, and the Pr and Ps at bending states are almost the same as compared to those at unbending state. Even in the convex and concave bending, the KNN thick films show excellent non-volatile memory characteristics. The Pr is almost the same even after the 108 times of switching and the 104 sec of retention.

Ordered mesoporous silica nanoparticles with and without embedded iron oxide nanoparticles: structure evolution during synthesis

Suteewong, Teeraporn,Sai, Hiroaki,Lee, Jinwoo,Bradbury, Michelle,Hyeon, Taeghwan,Gruner, Sol M.,Wiesner, Ulrich Royal Society of Chemistry 2010 Journal of materials chemistry Vol.20 No.36

<P>This work reports on the structural evolution during room temperature synthesis of hexagonally ordered mesoporous silica nanoparticles with and without embedded iron oxide particles. Oleic acid-capped iron oxide nanoparticles are synthesized and transferred to an aqueous phase using the cationic surfactant, hexadecyltrimethylammonium bromide (CTAB). MCM-41 type silica and composite nanoparticles are fabricated <I>via</I> sol–gel synthesis. Aliquots are taken from the solution during synthesis to capture the particle formation process. Transmission Electron Microscopy (TEM) and Small Angle X-ray Scattering (SAXS) reveal a transition from a disordered to an ordered structure in both synthesis systems. Along with the evolution of structure, iron oxide nanoparticles acting as seeds at the early stages are relocated from the particle centers to the edges. Nitrogen sorption measurements for iron oxide-embedded mesoporous nanoparticles indicate surface areas as high as for the mesoporous silica nanoparticles without iron oxide.</P> <P>Graphic Abstract</P><P>We report on the structural evolution during synthesis of ordered mesoporous silica nanoparticles with and without embedded magnetic nanoparticles. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c0jm01002b'> </P>

충남 일부지역 초등학생의 인두에 분포하는 세균 실태조사

하서영,박수진,이보미,박솔기,박창은 남서울대학교 2012 남서울대학교 논문집 Vol.18 No.2

The distributed species and the kinds of variable microorganism in Pharynx were monitored to the elementary school child. Our purpose was to investigate the distribution of bacteria in Pharynx of child except for adults. Analysis performed the collected sample from 15 students in Chungnam area for 2 days from July 30 to July 31 in 2012. The isolated bacteria were identified by Gram stain and biochemical test using VITEKⅡsystems. The experiment on microorganism concentration of contact parts carried out and the average of total microorganism was measured. The elementary child's Pharynx were isolated and identified. The isolation rates were major distributied to Gram positive cocci, another Gram negative bacilli and Gram positive bacilli. respectively. The frequently isolated bacteria were G. adiacens. The Granulicatella adiacens is one of the fastidious Gram positive cocci previously described as nutritionally variant streptococci due to their requirement of L-cysteine, pyridoxal, or thiol compounds for growth. These bacteria have been identified as significant causative agents of endocarditis, opthalmic infections, and meningitis. Further systematic studies are necessary with an emphasis on species identification. Key Words : Microorganism, Elementary child, Pharynx and Larynx

경사진 트레드밀에서 후방보행운동을 통한 넙다리네갈래근 강화와 요통의 관계

박주완,김경,김형욱,김재우,배솔희,서정표,이정구,정하영 대구대학교 특수교육재활과학연구소 2010 再活科學硏究 Vol.28 No.1

목적: 본 연구에서는 경사진 트레드밀에서의 후방 보행 훈련을 통한 넙다리네갈래근의 강화가 요통 환자의 치료에 미치는 영향을 알아보고자 하였다. 대상: 만성 요통을 호소하는 16명의 환자를 대상으로 연구를 실시 하였다. 방법: 트레드밀을 10° 경사로 맞춰놓은 상태에서 대상자들은 하루 20분, 일주일에 3회의 빈도로 2주 동안 훈련을 하였다. 표면 근전도를 가지고 넓다리 곧은근, 안쪽 넓은근, 가쪽 넓은근, 척추 세움근의 %MVIC를 측정하였고, KODI와 VAS를 통해 대상자들의 통증정도를 측정하였다. 결과: 넓다리 곧은근은 훈련전에 비해 훈련을 하고 난 후 상대적으로 높은 근전도를 보였고, 통계적으로 유의하였다(p<.05). 안쪽 넓은근과 가쪽 넓은근 또한 높은 근전도율을 보였지만 통계적으로 유의하지는 않았다. 척추 세움근은 훈련전에 비해 훈련을 하고 난 후 높은 근전도율을 보여주었고, 통계적으로 유의하였다(p<.05). VAS와 KODI의 평균값은 명백하게 감소되었고, 통계적으로 유의하였다(p<.05). 결론: 이상의 결론을 종합하면, 후방보행을 통한 넙다리네갈래근의 강화는 요통의 감소에 효과적이라고 사료되며, 더불어 넙다리네갈래근으로 접근하여 요통을 경감하는 중재방법이 효과적인 치료 방법이 될 수 있다는 것을 의미한다. Purpose: This study was to investigate the influence of strengthening the Quadriceps femoris through backward walking treadmill training in the patients who have lower back pain. Subjects: Sixteen subjects with chronic lower back pain were included. Method: In the training, the treadmill was set to have a inclination of 10 degrees, and the subjects were trained for 20 minutes a day, 3 times a week, for 2 weeks. %MVIC(muscle power) of rectus femoris, vastus medialis oblique, vastus lateralis and erctor spinae were measured with surface EMG, and KODI and VAS were used to measure the subject's level of pain. Results: Quadriceps femoris showed relatively higher average electromyogram rates than that before training(p<.05). Vastus medialis oblique and vastus lateralis also showed higher average electromyogram rates, but no significant change in them was noted. Erector spinae showed higher average electromyogram rates than that before training(p<.05). The average points of VAS and KODI clearly decreased(p<.05). Conclusion: Strengthening Quadriceps femoris seems to be efficient for relieving lower back pain in this study.