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Strange attractors, spiritual interlopers and lonely wanderers:The search for pre-Pangean supercontinents

geoscience Frontiers 2014年第2期5卷 155-166页

作者： joseph g.Meert Department of geological Sciences 355 Williamson Hall University of Florida

The observation is made that there are very strong similarities between the supercontinents Columbia, Rodinia and Pangea. If plate tectonics was operating over the past 2.5 billion years of Earth history, and dominated by extroversion and introversion of ocean basins, it would be unusual for three superconti-nents to resemble one another so closely. The term＇strange attractor＇ is applied to landmasses that form a coherent geometry in all three supercontinents. Baltica, Laurentia and Siberia form a group of＇strange attractors＇ as do the elements of East gondwana （India, Australia, Antarctica, Madagascar）. The elements of ＂West gondwana＂ are positioned as a slightly looser amalgam of cratonic blocks in all three super-continents and are referred to as ＇spiritual interlopers＇. Relatively few landmasses （the South China, North China, Kalahari and perhaps Tarim cratons） are positioned in distinct locations within each of the three supercontinents and these are referred to as＇lonely wanderers＇. 〈br〉 There may be several explanations for why these supercontinents show such remarkable similarities. One possibility is that modern-style plate tectonics did not begin until the late Neoproterozoic and horizontal motions were restricted and a vertical style of ＇lid tectonics＇ dominated. If motions were limited for most of the Proterozoic, it would explain the remarkable similarities seen in the Columbia and Rodinia supercontinents, but would still require the strange attractors to rift, drift and return to approximately the same geometry within Pangea. 〈br〉 A second possibility is that our views of older supercontinents are shaped by well-known connections documented for the most recent supercontinent, Pangea. It is intriguing that three of the four ＇lonely wanderers＇（Tarim, North China, South China） did not unite until just before, or slightly after the breakup of Pangea. The fourth＇lonely wanderer＇, the Kalahari （and core Kaapvaal） craton has a somewhat unique Archean-age geo

关键词： Columbia Rodinia Pangea Supercontinent Tectonics

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Anaerobic bacteria and intrahepatic stones: detections of Clostridium sp. and Bacteroides fragilis

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Chinese Medical Journal 2000年第9期113卷 90-93页

作者： LIU Yanlei Kan Lam Yajarayma J Tang Paul H gumerlock Dong Ki Lee Myung hwa Kim Sum P Lee joseph SilvaJr joseph W Leung Division of gastroenterology and Mr & MrsCWLaw Biofilm Research Center University of CaliforniaDavis MedicalCenterSacramentoCA95817USA

To detect anaerobic bacteria Clostridium sp . and Bacteroides fragilis in intrahepatic stones by molecular genetic method Methods DNA was extracted from 59 stone samples and subjected to polymerase chain reaction (PCR) amplification targeting the 16S rRNA gene of Clostridium sp . and the glutamine synthetase gene of Bacteroides fragilis Single-strand conformational polymorphism (SSCP) analysis was performed to identify the Clostridium sp Results 16S rRNA gene sequences for Clostridium sp. were identified in 49 stones (83%, 49/59) The two most common groups were detected in 19 (41%) and 17 (37%) of the 46 samples using SSPC analysis, and 25/59 (42%) stones were tested positive for Bacteroides fragilis Conclusions Anaerobes such as Clostridium sp and Bacteroides fragilis present in intrahepatic stones and may play a role in stone formation PCR is a useful technique to detect fastidious pathogens, which are difficult to culture SSCP of PCR products is a rapid method in differentiating bacterial species

关键词： intrahepatic stone anaerobic bacteria PCR single-strand confromational polymorphism

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Recent progress of advanced anode materials of lithium-ion batteries

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Journal of Energy Chemistry 2021年第6期30卷 451-468,I0011页

作者： Hui Cheng joseph g.Shapter Yongying Li guo gao Key Laboratory for Thin Film and Micro Fabrication of the Ministry of Education Department of Instrument Science and TechnologySchool of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Australian Institute of Bioengineering and Nanotechnology(AIBN) University of QueenslandSt.LuciaQueensland 4072Australia

The rapid development of electric vehicles and mobile electronic devices is the main driving force to improve advanced high-performance lithium ion batteries(LIBs).The capacity,rate performance and cycle stability of LIBs rely directly on the electrode *** far as the development of the advanced LIBs electrode is concerned,the improvement of anode materials is more urgent than the cathode *** production of anode materials superior to commercial graphite still faces some *** review sets out the most basic LIBs anode material *** reaction principles and structural design of carbon materials,various transition metal oxides,silicon and germanium are summarized,and then the progress of other anode materials are *** to the rapid development of metal organic frameworks(MOFs)in energy storage and conversion in recent years,the synthesis process and energy storage mechanism of nanostructures derived from MOF precursors are also *** the perspective of novel structural design,the progress of various MOFs-derived materials for alleviating the volume expansion of anode materials is ***,challenges for the future development of advanced anode materials for LIBs will be considered.

关键词： Anode materials LIBs Nanomaterials Metal organic frameworks

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The Fourier space restricted Hartree-Fock method for the electronic structure calculation of linear poly(tetrafluoroethylene)

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Science China Chemistry 2014年第10期57卷 1355-1362页

作者： FRIPIAT joseph g. HARRIS Frank E. Laboratoire de Chimie Théorique Unité de chimie physique théorique et structurale University of NamurRue de Bruxelles Department of Physics University of Utah Quantum Theory Project University of Florida

Building on the pioneering work of Jean-Marie Andre and working in the laboratory he founded, the authors have developed a code called FT-1D to make Hartree-Fock electronic structure computations for stereoregular polymers using Ewald-type con- vergence acceleration methods. That code also takes full advantage of all line-group symmetries to calculate only the minimal set of two-electron integrals and to optimize the computation of the Fock matrix. The present communication reports a bench- mark study of the FT-1D code using polytetrafluoroethylene （PTFE） as a test case. Our results not only confirm the algorith- mic correctness of the code through agreement with other studies where they are applicable, but also show that the use of con- vergence acceleration enables accurate results to be obtained in situations where other widely-used codes （e.g., PLH and Crys- tal） fail. It is also found that full attention to the line-group symmetry of the PTFE polymer leads to an increase of between one and two orders of magnitude in the speed of computation. The new code can therefore be viewed as extending the range of electronic-structure computations for stereoregular polymers beyond the present scope of the successful and valuable code Crystal.

关键词： poly(tetrafluoroethylene) band structure Fourier-space Hartree-Fock lattice sum Ewaid

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Age of the Marwar Supergroup,NW India:A note on the U–Pb geochronology of Jodhpur group felsic volcanics

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geoscience Frontiers 2022年第1期13卷 244-254页

作者： Huiru Xu joseph g.Meert Manoj K.Pandit Hubei Subsurface Multi-scale Imaging Key Laboratory Institute of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China Department of Earth and Planetary Sciences University of FloridaGainesvilleFL 32611United States Department of geology University of RajasthanJaipur 302004India

The Marwar Supergroup(NW Peninsular India)is thought to be of Ediacaran-Cambrian age,based on previous paleontological and geochronological ***,direct constraints on the onset of sedimentation within the Marwar basin are still *** this study,we report U–Pb zircon,LA-ICP-MS,and SIMS ages from the Chhoti Khatu felsic volcanic rocks,interlayered with the Jodhpur group sandstones(Lower Marwar Supergroup).The cathodoluminescence images of the zircons indicate complex morphologies,and core-rim textures coupled with the wide range of ages indicate that they are likely inherited or in the case of thin poorly indurated ash-beds,detrital in *** age spectra of 68 zircon analyses from our sampling display a dominant 800–900 Ma age peak corresponding to the age of basement"Erinpura granite"rocks in the *** youngest inherited zircon from a felsic ash layer yielded a U–Pb age of651 Ma±18 Ma that,together with previous studies and paleontological evidence,indicates a postCryogenian age for the initiation of Marwar sedimentation following a~125 Ma hiatus between the end of Malani magmatism and Marwar deposition.

关键词： Marwar Supergroup Sedimentation age Zircon U-Pb dating Chhoti Khatu felsic volcanics

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From thermal conductive to thermal insulating:Effect of carbon vacancy content on lattice thermal conductivity of ZrC_(x)

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Journal of Materials Science & Technology 2021年第23期82卷 105-113页

作者： Yue Zhou William g.Fahrenholtz joseph graham gregory E.Hilmas Department of Materials Science and Engineering Missouri University of Science and TechnologyRollaMO 65409USA

Lattice thermal conductivities of zirconium carbide(ZrC_(x),x=1,0.75 and 0.5)ceramics with different carbon vacancy concentrations were calculated using a combination of first-principles calculations and the Debye-Callaway *** gruneisen parameters,Debye temperatures,and phonon group velocities were deduced from phonon dispersions of ZrC_(x) determined using first-principles *** addition,the effects of average atomic mass,grain size,average atomic volume and Zr isotopes on the lattice thermal conductivities of ZrC_(x) were analyzed using phonon scattering *** lattice thermal conductivity decreased as temperature increased for ZrC,ZrC_(0.75) and ZrC_(0.5)(Zr2 C),and decreased as carbon vacancy concentration ***,ZrC_(x) can be tailored from a thermal conducting material for ZrC with high lattice thermal conductivity to a thermal insulating material for ZrC_(0.5) with low lattice thermal ***,it opens a window to tune the thermal properties of ZrC_(x) by controlling the carbon vacancy content.

关键词： Zirconium carbide Lattice thermal conductivity Theoretical study First-principle calculations

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Recent progress in sulfur cathodes for application to lithium-sulfur batteries

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Particuology 2021年第5期19卷 1-15页

作者： Yongying Li joseph g.Shapter Hui Cheng guiying Xu guo gao Key Laboratory for Thin Film and Micro Fabrication of the Ministry of Education Department of Instrument Science and TechnologySchool of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Australian Institute of Bioengineering and Nanotechnology(AIBN) University of QueenslandSt.LuciaQueensland 4072Australia

Owing to the extensive use of fossil fuels for energy,environmental problems are becoming increasingly ***,renewable clean energy sources must be urgently *** an environmentally friendly electrochemical energy-storage system,lithium-ion batteries(LIBs)are widely used in portable devices,electric vehicles,and medical ***,owing to their high cost and low theoretical energy density,LIBs are far from meeting the current energy ***-sulfur batteries(LSBs)(wherein lithium metal and sulfur are the anode and cathode,respectively)are one of the most valuable secondary batteries because of their high theoretical energy density(-2600Whkg^(-1)).However,the intrinsic conductivity of sulfur cathode materials is poor,and the lithium polysulfide formed during lithiation dissolves ***,the volumetric expansion during charging and discharging adversely affects the LSB electrochemical performance,including the rate performance,cycle life,and coulombic ***,to improve the LSB electrochemical performance,various sulfur composites have been prepared using carbon materials,metallic oxides,and conductive polymers,and various composite cathode materials recently developed for application to LSBs were ***,research directions were proposed for modifying LSB cathode materials.

关键词： Lithium-sulfur batteries(LSBs) Cathode materials Hybrid composites Energy storage

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Periodontitis:An often-neglected complication of diabetes

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World Journal of Diabetes 2024年第3期15卷 318-325页

作者： Marina g Kudiyirickal joseph M Pappachan Primary Care Dental Practice The Smile ClinicPreston PR16PZUnited Kingdom Department of Endocrinology and Metabolism Lancashire Teaching Hospitals NHS TrustPreston PR29HTUnited Kingdom Faculty of Science Manchester Metropolitan UniversityManchester M156BHUnited Kingdom Faculty of Biology Medicine and HealthThe University of ManchesterManchester M139PLUnited Kingdom

The bidirectional association between type 2 diabetes mellitus(T2DM)and periodontitis is now well established,resulting in periodontal disease being considered as the 6th major complication of diabetes mellitus(DM)after cardiovascular disease,eye disease,neuropathy,nephropathy,and peripheral vascular *** can worsen the virulence and invasiveness of pathogenic oral microbial flora aggravating the local inflammation and infection in those with periodontal *** the other hand,the chemical and immunological mediators released into the circulation as part of periodontal inflammation worsen the systemic insulin resistance with worsening of *** if undiagnosed or left untreated can also result in eventual tooth loss.A study by Xu et al in the World Journal of Diabetes examined the predictive factors associated with periodontitis in Chinese patients with *** prevalence of periodontitis was found to be 75.7%in this *** on logistic regression analysis,the predictive factors for higher risk were low tooth brushing frequency[odds ratio(OR)=4.3],high triglycerides(Tg;OR=3.31),high total cholesterol(TC;OR=2.87),higher glycated hemoglobin(HbA1c;OR=2.55),and higher age(OR=1.05)while higher education level was protective(OR=0.53).However,the most influential variables were HbA1c followed by age,TC,Tg,low education level,brushing frequency,and sex on the random forest model(this model showed higher sensitivity for predicting the risk).A good understanding of the predictors for periodontitis in T2DM patients is important in prevention,early detection of susceptible patients,and intervention to improve periodontal health and enable long-term glycaemic control as observed by Xu et al.

关键词： Diabetes mellitus Periodontitis Predictive factors Cardiovascular disease glycaemic control

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A proposed modulatory role of the endocannabinoid system on adipose tissue metabolism and appetite in periparturient dairy cows

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Journal of Animal Science and Biotechnology 2021年第3期12卷 995-1007页

作者： Madison N.Myers Maya Zachut joseph Tam g.Andres Contreras Department of Large Animal Clinical Sciences College of Veterinary MedicineMichigan State UniversityEast LansingMI 48824USA Department of Ruminant Science Institute of Animal SciencesAgricultural Research Organization/Volcani Center7505101 Rishon LeZionIsrael Obesity and Metabolism Laboratory The Institute for Drug ResearchSchool of PharmacyFaculty of MedicineThe Hebrew University of Jerusalem9112001 JerusalemIsrael

To sustain the nutrient demands of rapid fetal growth,parturition,and milk synthesis,periparturient dairy cows mobilize adipose tissue fatty acid stores through *** process induces an inflammatory response within AT that is resolved as lactation progresses;however,excessive and protracted lipolysis compounds the risk for metabolic and inflammatory *** suppression of lipolytic action and inflammation,along with amplification of adipogenesis and lipogenesis,serve as prospective therapeutic targets for improving the health of periparturient dairy ***,the activation of cannabinoid receptors by endocannabinoids enhances adipogenesis and lipogenesis,suppresses lipolysis,and increases appetite in *** biological effects of activating the endocannabinoid system open the possibility of harnessing the endocannabinoid system through nutritional intervention in dairy herds as a potential tool to improve dairy cows’health,although much is still to be revealed in this *** review summarizes the current knowledge surrounding the components of the endocannabinoid system,elaborates on the metabolic effects of its activation,and explores the potential to modulate its activity in periparturient dairy cows.

关键词： Adipogenesis Adipose tissue Dairy cow health Endocannabinoids Endocannabinoid system Lipogenesis Lipolysis

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EJUSTCO:Monte Carlo radiation transport code hybrid with ANN model for gamma-ray shielding simulation

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Nuclear Science and Techniques 2023年第9期34卷 155-176页

作者： joseph Konadu Boahen Ahmed S.g.Khalil Mohsen A.Hassan Samir A.Elsagheer Mohamed Materials Science and Engineering Department School of Innovative Design EngineeringEgypt-Japan University of Science and Technology(E-JUST)179New Borg El-Arab CityEgypt Physics Department Environmental and Smart Technology GroupFaculty of ScienceFayoum UniversityFayoum 63514Egypt Faculty of Engineering Aswan UniversityAswanEgypt

gamma ray shielding is essential to ensure the safety of personnel and equipment in facilities and environments where radiation *** Monte Carlo technique is vital for analyzing the gamma-ray shielding capabilities of *** this study,a simple Monte Carlo code,EJUSTCO,is developed to cd simulate gamma radiation transport in shielding materials for academic *** code considers the photoelectric effect,Compton(incoherent)scattering,pair production,and photon annihilation as the dominant interaction mechanisms in the gamma radiation shielding *** reduction techniques,such as the Russian roulette,survival weighting,and exponential transformation,are incorporated into the code to improve computational *** the exponential transformation parameter typically requires trial and error as well as ***,a deep learning neural network is proposed as a viable method for predicting this parameter for the first *** model achieves an MSE of 0.00076752 and an R-value of *** exposure buildup factors and radiation dose rates due to the passage of gamma radiation with different source energies and varying thicknesses of lead,water,iron,concrete,and aluminum in single-,double-,and triple-layer material systems are validated by comparing the results with those of MCNP,ESg,ANS-6.4.3,MCBLD,MONTEREY MARK(M),PENELOPE,and *** errors of 5.6%,2.75%,and 10%are achieved for the exposure buildup factor in single-,double-,and triple-layer materials,respectively.A significant parameter that is not considered in similar studies is the gamma ray *** the EJUSTCO code,the total number and energy albedos have been *** results are compared with those of MCNP,FOTELP,and *** general,the EJUSTCO-developed code can be employed to assess the performance of radiation shielding materials because the validation results are consistent with theoretical,experimental,and literary results.

关键词： Monte Carlo gamma rays Shielding Artificial neural network Simulation

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