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UBVVI Surface Photometry of the Spiral Galaxy NGC 300 in the Sculptor Group

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Chinese Journal of Astronomy and Astrophysics 2004年第4期4卷 299-310页

作者： sang chul kim Hwankyung Sung Hong Soo Park Eon-Chang Sung Korea Astronomy Observatory Taejon 305-348Republic of KoreaDepartment of Astronomy and Space ScienceSejong University98 Gunja-dongGwangjin-guSeoul 143-747Republic of KoreaAstronomy ProgramSEESSeoul National UniversitySeoul 151-742Republic of KoreaKorea Astronomy ObservatoryTaejon 305-348Republic of Korea

We present UBVI surface photometry over a 20.5' × 20.5' area of the late-type spiral galaxy NGC 300. We have derived isophotal maps, surface brightness profiles, ellipticity profiles, position angle profiles, and color profiles. By merging our I-band measurements with those of Boker et al. based on Hubble Space Telescope observations, we have obtained combined I-band surface brightness profiles for the region 0.02' < r < 500' and have decomposed the profiles into three components: a nucleus, a bulge, and an exponential disk.

关键词： galaxies: spiral - galaxies: photometry - galaxies: individual(NGC 300) - galaxies: nuclei

Transcriptional Regulation of Lipid Catabolism during Seedling Establishment

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Molecular Plant 2020年第7期13卷 984-1000页

作者： Guangqin Cai sang-chul kim Jianwu Li Yongming Zhou Xuemin Wang National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070China Department of Biology University of MissouriSt.LouisMO 63121USA Donald Danforth Plant Science Center St.LouisMO 63132USA Henan Agricultural University ZhengzhouHenan 450002China

Lipid catabolism in germinating seeds provides energy and substrates for initial seedling growth,but how this process is regulated is not well ***,we show that an AT-hook motif-containing nuclear localized(AHL)protein regulates lipid mobilization and fatty acid p-oxidation during seed germination and seedling ***4 was identified to directly interact with the lipid mediator phosphatidic acid(PA).Knockout(KO)of AHL4 enhanced,but overexpression(OE)of AHL4 attenuated,triacylglycerol(TAG)degradation and seedling *** seedling growth of the OE lines was restored by sucrose supplementation to the growth ***4-OE seedlings displayed decreased expression of genes involved in TAG hydrolysis and fatty acid oxidation,whereas the opposite was observed in *** genes contained AHL4-binding cis elements,and AHL4 was shown to bind to the promoter regions of genes encoding the TAG lipases SDP1 and DALL5 and acyl-thioesterase *** AHL4-DNA interactions were suppressed by PA species that bound to *** results indicate that AHL4 suppresses lipid catabolism by repressing the expression of specific genes involved in TAG hydrolysis and fatty acid oxidation,and that PA relieves AHL4-mediated suppression and promotes TAG ***,AHL4 and PA together regulate lipid degradation during seed germination and seedling establishment.

关键词： lipid catabolism lipid regulation phosphatidic acid seed germination seedling establishment transcriptional regulation

Near-infrared studies of nova V5584 Sgr in the pre-maximum and early decline phase

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Research in Astronomy and Astrophysics 2015年第7期15卷 993-1004页

作者： Ashish Raj D.P.K.Banerjee N.M.Ashok sang chul kim Korea Astronomy and Space Science Institute (KASI) Physical Research Laboratory Korea University of Science and Technology (UST)

We present near-infrared spectroscopic and photometric observations of nova V5584 Sgr taken during the first 12 d following its discovery on Oct. 26.439 UT2009. The evolution of the spectra is shown from the initial P Cygni phase to an emission line phase. The prominent carbon lines seen in the JHK spectra closely match those observed in an Fe II class nova outburst. The spectra show first-overtone CO bands in emission between 2.29-2.40 μm. By examining WISE and other publicly available data, we show that the nova underwent a pronounced dust formation phase between February- April 2010.

关键词： line: identification -- techniques: spectroscopic -- stars: individual(V5584 Sgr) -- novae cataclysmic variables

Effects of mesenchymal stem cell on dopaminergic neurons,motor and memory functions in animal models of Parkinson's disease:a systematic review and meta-analysis

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Neural Regeneration Research 2024年第7期19卷 1584-1592页

作者： Jong Mi Park Masoud Rahmati sang chul Lee Jae Il Shin Yong Wook kim Department and Research Institute of Rehabilitation Medicine Yonsei University College of MedicineSeoulSouth Korea Department of Physical Education and Sport Sciences Faculty of Literature and Human SciencesLorestan UniversityKhoramabadIran Department of Pediatrics Yonsei University College of MedicineSeoulSouth Korea

Parkinson’s disease is chara cterized by the loss of dopaminergic neurons in the substantia nigra pars com pacta,and although restoring striatal dopamine levels may improve symptoms,no treatment can cure or reve rse the disease *** cell therapy has a regenerative effect and is being actively studied as a candidate for the treatment of Parkinson’s *** stem cells are considered a promising option due to fewer ethical concerns,a lower risk of immune rejection,and a lower risk of *** performed a meta-analysis to evaluate the therapeutic effects of mesenchymal stem cells and their derivatives on motor function,memory,and preservation of dopamine rgic neurons in a Parkinson’s disease animal *** searched bibliographic databases(PubMed/MEDLINE,Embase,CENTRAL,Scopus,and Web of Science)to identify articles and included only pee r-reviewed in vivo interve ntional animal studies published in any language through J une 28,*** study utilized the random-effect model to estimate the 95%confidence intervals(CI)of the standard mean differences(SMD)between the treatment and control *** use the systematic review center for laboratory animal expe rimentation’s risk of bias tool and the collaborative approach to meta-analysis and review of animal studies checklist for study quality assessment.A total of 33studies with data from 840 Parkinson’s disease model animals were included in the *** with mesenchymal stem cells significantly improved motor function as assessed by the amphetamine-induced rotational *** the stem cell types,the bone marrow MSCs with neurotrophic factor group showed la rgest effect size(SMD[95%CI]=-6.21[-9.50 to-2.93],P=0.0001,I^(2)=0.0%).The stem cell treatment group had significantly more tyrosine hydroxylase positive dopamine rgic neurons in the striatum([95%CI]=1.04[0.59 to 1.49],P=0.0001,I^(2)=65.1%)and substantia nigra(SMD[95%CI]=1.38[0.89 to 1.87],P=0.0001,I^(2)=75.3%),indicating a

关键词： animal animal experimentation mesenchymal stem cells models Parkinson’s disease stem cell transplantation

Ionizing terahertz waves with 260 MV/cm from scalable optical rectification

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Light(Science & Applications) 2024年第6期13卷 1075-1087页

作者： Hyeongmun kim chul Kang Dogeun Jang Yulan Roh sang Hwa Lee Joong Wook Lee Jae Hee Sung Seong Ku Lee Ki-Yong kim Advanced Photonics Research Institute GISTGwangju61005Korea Department of Physics and Optoelectronics Convergence Research Center Chonnam National UniversityGwangju61186Korea Pohang Accelerator Laboratory POSTECHPohang37673Korea Center for Relativistic Laser Science Institute for Basic ScienceGwangju61005Korea Institute for Research in Electronics and Applied Physics Department of PhysicsUniversity of MarylandCollege ParkMaryland20742USA

Terahertz(THz)waves,known as non-ionizing radiation owing to their low photon energies,can actually ionize atoms and molecules when a sufficiently large number of THz photons are concentrated in time and ***,we demonstrate the generation of ionizing,multicycle,15-THz waves emitted from large-area lithium niobate crystals via phase-matched optical rectification of 150-terawatt laser pulses.A complete characterization of the generated THz waves in energy,pulse duration,and focal spot size shows that the field strength can reach up to 260 megavolts per *** particular,a single-shot THz interferometer is employed to measure the THz pulse duration and spectrum with complementary numerical *** intense THz pulses are irradiated onto various solid targets to demonstrate THz-induced tunneling ionization and plasma *** study also discusses the potential of nonperturbative THz-driven ionization in gases,which will open up new opportunities,including nonlinear and relativistic THz physics in plasma.

关键词： optical interferometer matched

Nanocrystalline low-silica X zeolite as an efficient ion-exchanger enabling fast radioactive strontium capture

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 15-23页

作者： Hyungmin Jeon Susung Lee Jeong-chul kim Minkee Choi Department of Chemical and Biomolecular Engineering(BK21 Four) Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea Center for Nanomaterials and Chemical Reactions Institute for Basic Science(IBS)Daejeon 34141Republic of Korea

NaA zeolite(Si/Al=1.00)has been commercially applied for capturing radioactive 90Sr^(2+)because of its high surface charge density,effectively stabilizing the multivalent ***,owing to its narrow micropore opening(4.0Å),large micron-sized crystallites,and bulkiness of hydrated Sr^(2+),the Sr^(2+)exchange over NaA has been limited by very slow *** this study,we synthesized nanocrystalline low-silica X by minimizing a water content in a synthesis gel and utilizing a methyl cellulose hydrogel as a crystal growth *** resulting zeolite exhibited high crystallinity and Al-rich framework(Si/Al of approximately 1.00)with the sole presence of tetrahedral Al sites,which are capable of high Sr^(2+)uptake and ion ***,the zeolite with a FAU topology has a much larger micropore opening size(7.4Å)and a much smaller crystallite size(~340 nm)than NaA,which enable significantly enhanced ion-exchange *** to conventional NaA,the nanocrystalline low-silica X exhibited remarkably increased Sr^(2+)-exchange kinetics(>18-fold larger rate constant)in batch *** both the nanocrystalline low-silica X and NaA exhibited comparable Sr^(2+)capacities under equilibrated conditions,the former demonstrated a 5.5-fold larger breakthrough volume than NaA under dynamic conditions,attributed to its significantly faster Sr^(2+)-exchange kinetics.

关键词： Sr^(2+)removal low-silica X zeolite nanocrystal hydrogel methyl cellulose

Opportunities and challenges in cathode development for non-lithium-ion batteries

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eScience 2024年第4期4卷 1-6页

作者： Haegyeom kim Jae chul kim Materials Sciences Division Lawrence Berkeley National Laboratory94720CAUSA Department of Chemical Engineering and Materials Science Stevens Institute of Technology07030NJUSA

Lithium(Li)-ion batteries have stimulated the societal transformation to clean energy *** carry-on electricity is revolutionizing how society communicates,functions,and evolves efficiently by enabling mobile electronics,zero-emission electric vehicles,and stationary energy *** preparation for the sustainable energy future,however,there are growing concerns about depleting critical elements used in the Li technology(e.g.,lithium,cobalt,and nickel),especially for large-scale applications that will accelerate the rate of elemental *** non-Li-based rechargeable batteries composed of earth-abundant elements,such as sodium,potassium,magnesium,and calcium,have been proposed and explored as alternative systems to promote sustainable development of energy *** this perspective,we discuss challenges in Li-ion batteries in the sustainability aspect and provide our opinions on the potential applications of non-Li-based *** also highlight the current status,important progress,and remaining challenges of the Li-alternative technologies.

关键词： Batteries Sodium Potassium Lithium Multi-valent Energy storage

Functionally graded structure of a nitride-strengthened Mg_(2)Si-based hybrid composite

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Journal of Magnesium and Alloys 2024年第3期12卷 1239-1256页

作者： Jeongho Yang Woongbeom Heogh Hogi Ju Sukhyun Kang Tae-Sik Jang Hyun-Do Jung Mohammad Jahazi Seung chul Han Seong Je Park Hyoung Seop kim Susmita Bose Amit Bandyopadhyay Martin Byung-Guk Jun Young Won kim Dae-kyeom kim Rigoberto CAdvincula Clodualdo Aranas Jr sang Hoon kim School of Mechanical Engineering Pusan National UniversityBusan 46241Republic of Korea Department of Mechanical Design Engineering Hanyang UniversitySeoul 04763Republic of Korea Process Research 3 Team LG Display Co.Ltd.PajuGyeonggi-do 10845Republic of Korea Department of Materials Science and Engineering Chosun UniversityGwangju 61452Republic of Korea Institute of Well-Aging Medicare&Chosun University LAMP Center Chosun UniversityGwangju 61452Republic of Korea Division of Materials Science and Engineering Hanyang UniversitySeoul 04763Republic of Korea Department of Mechanical Engineering École de Technologie SupérieureMontrealQuebec H3C 1K3Canada Material&Component Convergence R&D Center Korea Construction Equipment Technology InstituteGunsanJeollabuk-do 54002Republic of Korea School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore Graduate Institute of Ferrous&Eco Materials Technology Pohang University of Science and TechnologyPohangGyeongsangbuk-do 37673Republic of Korea Advanced Institute for Materials Research Tohoku UniversitySendai 980-8577Japan Institute for Convergence Research and Education in Advanced Technology Yonsei UniversitySeoul 03722Republic of Korea School of Mechanical and Materials Engineering Washington State UniversityPullmanWashington 99164USA School of Mechanical Engineering Purdue UniversityWest LafayetteIndiana 47907USA Research Institute of Advanced Manufacturing Technology Korea Institute of Industrial TechnologyIncheon 21999Republic of Korea Department of Macromolecular Science and Engineering Case Western Reserve UniversityClevelandOhio 44106USA Department of Chemical and Biomolecular Engineering and Joint Institute for Advanced Materials University of TennesseeKnoxvilleTennessee 37996USA Center for Nanophase Materials and Sciences Oak Ridge National LaboratoryOak RidgeTennessee 37830USA Department of Mechanical Engineering University of New BrunswickFrederictonNew Brunswick E3B 5A3Cana

The ex-situ incorporation of the secondary SiC reinforcement,along with the in-situ incorporation of the tertiary and quaternary Mg_(3)N_(2) and Si_(3)N_(4) phases,in the primary matrix of Mg_(2)Si is employed in order to provide ultimate wear resistance based on the laser-irradiation-induced inclusion of N_(2) gas during laser powder bed *** is substantialized based on both the thermal diffusion-and chemical reactionbased metallurgy of the Mg_(2)Si–SiC/nitride hybrid *** study also proposes a functional platform for systematically modulating a functionally graded structure and modeling build-direction-dependent architectonics during additive *** strategy enables the development of a compositional gradient from the center to the edge of each melt pool of the Mg_(2)Si–SiC/nitride hybrid ***,the coefficient of friction of the hybrid composite exhibits a 309.3%decrease to–1.67 compared to–0.54 for the conventional nonreinforced Mg_(2)Si structure,while the tensile strength exhibits a 171.3%increase to 831.5 MPa compared to 485.3 MPa for the conventional *** outstanding mechanical behavior is due to the(1)the complementary and synergistic reinforcement effects of the SiC and nitride compounds,each of which possesses an intrinsically high hardness,and(2)the strong adhesion of these compounds to the Mg_(2)Si matrix despite their small sizes and low concentrations.

关键词： Laser powder bed fusion Mg_(2)Si-SiC/nitride hybrid composite Both the thermal diffusion-and chemical reaction-based metallurgy Functionally graded structure Compositional gradient Wear resistance.

Development of immature ovarian teratoma after mature teratoma in a girl with familial ovarian teratoma:A case report

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World Journal of Clinical Cases 2024年第8期12卷 1442-1447页

作者： U chul Ju Woo Dae Kang Seok Mo kim Department of Obstetrics and Gynecology Chonnam National University Medical SchoolGwangju 61469South Korea

BACKGROUND Immature ovarian teratoma is a rare and aggressive neoplasm that affects young *** report is the first to describe the development of immature teratoma after ovarian cystectomy for mature teratoma of the ovary in an adolescent female with a family history of ovarian *** SUMMARY A 16-year-old girl who had undergone bilateral ovarian cystectomy for mature teratomas 3 years ago showed bilateral adnexal tumors during her regular ultrasonography follow-up every 6 *** received laparoscopic bilateral ovarian cystectomy,and final histopathology showed grade-1 immature teratoma of the left ovary and mature teratoma of the right *** left salpingo-oophorectomy and staging procedures were performed *** mother,maternal aunt,and maternal grandmother had also received surgeries for mature ovarian *** It is important to have guidance on management of patient and family members with familial ovarian teratomas.

关键词： Familial ovarian teratomas Adolescent female Immature ovarian teratoma Management Case report