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Paleozoic tectonic evolution of the proto-Korean Peninsula along the East Asian continental margin from detrital zircon U-Pb geochronology and Hf isotope geochemistry

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Geoscience Frontiers 2024年第1期15卷 97-117页

作者： Yirang Jang Sung Won Kim vinod O.Samuel Sanghoon Kwon Seung-Ik Park M.Santosh Keewook Yi Department of Earth and Environmental Sciences Chonnam National UniversityGwangju 61186Republic of Korea Geology Division Korea Institute of Geoscience and Mineral ResourcesDaejeon 34132Republic of Korea Department of Earth System Sciences Yonsei UniversitySeoul 03722Republic of Korea Department of Geology Kyungpook National UniversityDaegu 41566Republic of Korea School of Earth Sciences and Resources China University of Geosciences BeijingBeijing 100083China Department of Earth Science University of AdelaideAdelaide SA 5005Australia Yonsei Frontiers Lab Yonsei UniversitySeoul 03722Republic of Korea Division of Earth and Environmental Sciences Korea Basic Science InstituteChungbuk 28119Republic of Korea

Detrital zircon geochronology and Hf isotope analysis can be used for inferring provenance characteristics,and to evaluate the tectonic evolution of sedimentary basins and their link with regional *** Paleozoic sequences of the Okcheon belt consist of the Lower Paleozoic Joseon and the Upper Paleozoic Pyeongan supergroups with Middle Paleozoic hiatus locally on top of the Neoproterozoic bimodal volcanic rocks,reflecting an intracontinental rift setting between the two basements(*** and Yeongnam massifs)at southern part of the Korean *** detrital zircon U-Pb ages and Lu-Hf isotope results show that all these Paleozoic strata commonly have Paleoproterozoic and Paleozoic zircon ages with rare Meso-to Neoproterozoic *** individual zircon populations display following features,allowing estimation of their sedimentary provenances:(i)The Paleoproterozoic zircons(ca.1.85 Ga and 2.50 Ga)with similar ranges ofεHf(t)values are most common in the basement rocks of the Korean Peninsula,and were sourced from both the Gyeonggi and Yeongnam massifs.(ii)The Meso-to Neoproterozoic zircons,preserved only in the Middle to Late Cambrian clastic sedimentary rocks within the carbonate sequences probably reflect proximal provenance.(iii)The youngest Paleozoic zircons of each formation,almost coincident with their deposition ages,suggest presence of syndepositional magmatism,indicating proximal magmatic sources during their deposition.(iv)The Cambrian-Ordovician zircons,from the Lower Paleozoic sequences,but rare in the successive Upper Paleozoic sequences,suggest a provenance change after the hiatus between the two sedimentary successions.(v)The Permian zircons showing differentεHf(t)values indicate that detrital sources were varied at that *** integrated results in our study suggest provenance variability linked to diverse tectonic environments,reflecting prolonged subduction-related crustal evolution of the proto-Korean Peninsula during the Paleozo

关键词： Detrital zircon U-Pb and Hf isotopes Paleozoic metasedimentary rocks Okcheon belt Taebaeksan zone Korean Peninsula

A rare synchrony of adenocarcinoma of the ampulla with an ileal gastrointestinal stromal tumor: A case report

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World Journal of Gastrointestinal Oncology 2022年第11期14卷 2253-2265页

作者： Venkata vinod Kumar Matli Gazi b Zibari Gregory Wellman Poornima Ramadas Sudha Pandit James Morris Department of Internal Medicine Christus Highland Medical CenterShreveportLA 71106United States Division of Hepatobiliary Surgery Willis-Knighton Health SystemShreveportLA 711103United States Department of Gastrointestinal and Liver Pathology Christus Highland Medical CenterShreveportLA 71105United States Division of Hematology and Oncology Louisiana State University Health Sciences CenterShreveportLA 71103United States Division of Gastroenterology and Hepatology Louisiana State University Health Sciences CenterShreveportLA 71103United States

bACKGROUND This is a unique case of a patient who was found to have two extremely rare primary malignancies synchronously,i.e.,an ampullary adenocarcinoma arising from a high-grade dysplastic tubulovillous adenoma of the ampulla of Vater(TVAoA)with a high-grade ileal gastrointestinal stromal tumor(GIST).based on a literature review and to the best of our knowledge,this is the first report of this *** ampullary tumors are extremely rare,with an incidence of four cases per million population,which is approximately 0.0004%.Distal duodenal polyps are uncommon and have a preponderance of occurring around the ampulla of *** adenoma of the ampulla(AoA)may occur sporadically or with a familial inheritance pattern,as in hereditary genetic polyposis syndrome such as familial adenomatous polyposis syndrome(FAPS).We report a case of a 77-year-old male who was admitted for painless obstructive jaundice with a 40-pound weight loss over a two-month period and who was subsequently diagnosed with two extremely rare primary malignancies,i.e.,an adenocarcinoma of the ampulla arising from a high-grade TVAoA and a high-grade ileal GIST found *** SUMMARY A 77-year-old male was admitted for generalized weakness with an associated weight loss of 40 pounds in the previous two months and was noted to have painless obstructive *** physical examination was benign except for bilateral scleral and palmar *** results were significant for an obstructive pattern on liver *** lipase and carbohydrate antigen-19-9 levels were *** tomography(CT)of the abdomen and pelvis and magnetic resonance cholangiopancreatography were consistent with a polypoid mass at the level of the common bile duct(CbD)and the ampulla of Vater with CbD *** same lesions were visualized with endoscopic retrograde *** of endoscopic forceps biopsy showed *** of the surgical specimen of the

关键词： Tubulovillous adenoma of the ampulla of Vater Ampullary adenocarcinoma Gastrointestinal stromal tumor Ampullary polyp Small bowel mesenchymal tumor Case report

Assessment of geodetic strain and stress variations in Nepal due to 25 April 2015 Gorkha earthquake:Insights from the GNSS data analysis and b-value

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Geodesy and Geodynamics 2022年第3期13卷 288-300页

作者： Sravanthi Gunti Priyom Roy J.Narendran Ramesh Pudi S.Muralikrishnan K.vinod Kumar M.Subrahmanyam Y.Israel b.Satish Kumar National Remote Sensing Centre Indian Space Research Organization(ISRO)BalanagarHyderabad500037India Sustainability Risk Management Solutions of IndiaNoida201301India Department of Geophysics Andhra UniversityVisakhapatnam530003India

A magnitude M;7.8 earthquake occurred on 25 April 2015(referred as Gorkha earthquake).We have analyzed the spatial variation of b-value and two-dimensional strain within Nepal Himalaya before and after the Gorkha *** have used continuous Global Navigation Satellite System(GNSS)data from 30 stations in the Nepal region for geodetic strain estimation and earthquake data for b-value *** GNSS data were processed using double differencing technique for the accurate position of each *** precise velocity vectors show a general azimuth of north east for all the stations and have been used to derive two-dimensional *** epicenters of Gorkha(25 April 2015)and Dolakha earthquakes(12 May 2015),we observed high co-seismic horizontal displacements(0.2 m to 2 m).In the Pre-seismic deformation study,maximum strain accumulation(56.40×10;)and low bvalue(0.79-0.89)was observed in and around the Western Nepal region,which may be responsible for the 2015 Gorkha *** potential seismic zones were identified by GIS based integration of geodetic strain and b-value map and superimposition using weighted overlay *** Maximum strain and low b-value are now observed in the eastern part of ***,the spatial disposition of elastic energy has changed after the two major earthquakes and continuous seismic hazard assessment is required in the eastern Nepal.

关键词： Himalaya Co-seismic offsets bernese 5.2 UNAVCO Grid_Strain

Traversing the advantageous role of samarium doped spinel nanoferrites for photocatalytic removal of organic pollutants

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Journal of Rare Earths 2021年第7期39卷 781-789,I0002页

作者： Sneha Singh Paramdeep Kaur vinod Kumar K.b.Tikoo Sonal Singhal Department of Chemistry Panjab UniversityChandigarh160014India HRTEM Facility Lab NIPERSA.S.NagarMohaliPunjab160062India

The present work reportes the pertinence of samarium(Sm) doped spinel nanoferrites as magnetically recoverable photocatalyst for the removal of organic pollutants from ***,a series of Sm substituted spinel nano ferrites,MSm_(x)Fe_(2-x)O_(4)(M=Ni,Co;x=0,0.02,0.06,0.1) we re synthesized via sol-gel *** effect of Sm doping on the structural,morphological,optical and magnetic properties of pristine nanoferrites was investigated ***,the fabricated samples were explored as photocatalysts for the oxidative degradation of antibiotics(ofloxacin and norfloxacin) and dyes(methyl orange and safranin O).The Sm doped nanoferrites exhibit astonishing catalytic efficacy that can be attributed to higher surface area,octahedral site preference of Sm ions and reduced band *** synthesized nanoferrites display excellent recyclability which enables them to be utilized as potential photocatalysts for wastewater treatment.

关键词： Samarium doped nanoferrites Sol-gel Pharmaceutical degradation Recyclability Rare earths

A Positive Solution of Mixed Non-Linear Fractional Delay Differential Equations with Integral boundary Conditions

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Journal of Mathematical Research with Applications 2023年第2期43卷 213-226页

作者： Dayanand K.VYAVAHARE vinod V.KHARAT Department of Mathematics Punyashlok Ahilyadevi Holkar Solapur University Department of Mathematics N.B.Navale Sinhgad College of Engineering

In this paper, we study mixed non-linear fractional delay differential equations with integral boundary conditions. We obtain an equivalence result between the proposed problem and non-linear Fredholm integral equation of the second kind. Further, we establish existence and uniqueness of positive solutions for the problem using Guo-Krasnoseleskii’s fixed point theorem and banach contraction principle.

关键词： Guo-Krasnoseleskii’s fixed point theorem banach contraction principle mixed nonlinear fractional delay differential equations integral boundary conditions existence uniqueness

Spermine induced reversible collapse of deoxyribonucleic acid-bridged nanoparticle-based assemblies

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Nano Research 2018年第1期11卷 383-396页

作者： Kristian L. Goeken Richard b. M. Schasfoort vinod Subramaniam Ron Gill MIRA Institute for biomedical Technology and Technical Medicine University of Twente Dfienerlolaan 5 7522 NB Enschede the Netherlands Vrije UniversiteitAmsterdam De Boelelaan 1105 1081 HVAmsterdam the Netherlands Saxion University of Applied Sciences M. H. Tromplaan 28 7513 A8 Enschede the Netherlands

DNA-linked 2D and 3D nano-assemblies find use in a diverse set of applications, ranging from DNA-origami in drug delivery and medical imaging, to DNA-linked nanoparticle structures for use in plasmonics and （bio）sensing. However, once these structures have been fully assembled, few options are available to modulate structure geometry. Here, we investigated the use of the polycation spermine to induce DNA collapse in small oligonucleotide-linked （54 bp） gold nanoparticle structures by monitoring shifts in the localized surface plasmon resonance （LSPR） peak and by comparing the data with finite-difference time-domain （FDTD） simulations. Our data shows that low concentrations of spermine can be applied to induce large changes in DNA conformation, leading to a significant reduction in interparticle distance （from - 25 to - 3 nm） and enhanced plasmonic coupling. The DNA collapse is near-instantaneous and reversible, and its application at low and high DNA densities is demonstrated with surface plasmon resonance imaging （SPRi）, showing the potential of spermine to dynamically modulate distances and geometry in DNA-based nano-assemblies.

关键词： nanoparticles spermine deoxyribonucleic acid localized surface plasmonresonance surface plasmon resonanceimaging

Effect of Surface Roughness on Laser Induced Nonlinear Optical Properties of Annealed ZnO Thin Films

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Journal of Materials Science & Technology 2012年第6期28卷 506-511页

作者： Vinay Kumari vinod Kumar Devendra Mohan Purnima b.P.Malik R.M.Mehra Department of Physics BMIETSonepat 131001India Department of Physics DCRUSTMurthal 131027India Materials Science Group Inter University Accelerator CentreAruna Asaf Ali MargNew Delhi 110067India Department of Applied Physics GJUS&THisar 125001India School of Engineering and Technology Sharda UniversityGreater Noida 201306India

Variation of nonlinear optical properties with surface roughness of ZnO thin films deposited on coming glass substrates at different annealing temperature （TA） was reported. The films were characterized by X-ray diffraction （XRD）, UV-Vis-NIR transmission and single beam z-scan technique using second harmonics of Nd：YAG laser. Surface morphology of the samples was investigated by atomic force microscopy （AFM）. Surface roughness was found minimum （8.4 nm） for ZnO sample annealed at 450℃. The nonlinear optical properties （NLO） were found to be dependent on surface roughness and the highest value of third order nonlinear susceptibility （X（3）=4.3x 10-7 esu） was obtained for ZnO at TA 450℃.

关键词： ZnO films Sol-gel Annealing temperature Nonlinear optical properties Thirdorder nonlinear susceptibility z-scan

Progeny evaluation of Jatropha curcas and Pongamia pinnata with comparison to bioproductivity and biodiesel parameters

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Journal of Forestry Research 2015年第1期26卷 137-142页

作者： vinod Kumar Patil Prithviraj bhandare Pramod b. Kulkarni G.R.Naik Department of biotechnology Gulbarga University

Progeny studies of Jatropha curcas and Pongamia pinnata were carried with respect to bioproductivity,pod and seed characters which is one of the selection methods in tree improvement programmes. Variations in bioproductivity and biodiesel parameters of both the plants were compared every 6 months for 4 years of investigation and analyzed by analysis of variance and correlation coefficient by Pearson＇s method using software Graphpad instat 3.06（for Windows and Mac）. P. pinnata has better germination rate（71.4 %）, 100 pod weight（PW）（311.59 g） and 100 seed weight（SW）（173.46 g） as compared to J. curcas for germination rate（43.2 %）, 100 PW（111.29 g） and 100 SW（67.46 g）. P. pinnata has strong correlation for plant height to canopy growth（CG）（0.948）, collar diameter（CD）（0.994）, number of branches per plant（NbP）（0.995） and to number of leaves per branch（NLb）（0.862） as compared to *** which showed good correlation among plant height to CG（0.976）, CD（0.970）, NbP（0.988）, NLb（0.920） and to number of pods per branch（0.657）. However, J. curcas depicted negative correlation for pod breadth to seed length（SL）（-0.447）, seed breadth（-0.248） and to seed thickness（ST）（-0.364） and among the 100 PW to SL（-0.199）, ST（-0.220） and to 100 SW（-0.704）. About 4 kg of P. pinnata seeds were required for each liter of crude oil which yields896 ml of biodiesel on transesterification as compared to5.66 kg of J. curcas seeds for a liter of crude oil, producing about 663 ml of biodiesel. The quality of biodiesel meets the major specification of American Society for Testing and Materials（ASTM） standards for biodiesel. The crude glycerin and seed cake obtained as byproduct during biodiesel production were also measured which can be purified and used in composting, animal feeds, pharmaceuticals and cosmetic industries.

关键词： biodiesel biofuel plants bioproductivity Jatropha curcas Pongamia pinnata

Two-electron quantum ring in short pulses

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Chinese Physics b 2015年第2期24卷 46-52页

作者： Poonam Silotia Rakesh Kumar Meena vinod Prasad Department of Physics and Astrophysics University of Delhi Department of Physics Swami Shraddhanand CollegeUniversity of Delhi

The response of a two-electron quantum ring system to the short laser pulses of different shapes in the presence of external static electric field is *** variation of transition probabilities of the two-electron quantum ring from ground state to excited states with a number of parameters is shown and *** energy levels and wavefunctions of the system in the presence of static electric field are found by solving the time-independent Schrodinger equation numerically by the finite difference *** shape of the pulse plays a dominant role on the dynamics.

关键词： quantum ring ultrashort pulses transition probability