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International Journal of Biomathematics 2016年第6期9卷 273-306页

作者： Bibaswan Dey G. p. raja Sekhar Dep.rtment of MathematicsIndian Institute of Technology Kharagp.r Kharagp.r 721302 West Bengal India

Several biological p.ocesses, such as convective nutrient transp.rt and convective drug delivery in biological tissues involves the transvascular and interstitial movement of biofluids. This work addresses transvascular and interstitial transp.rt of nutrient inside a sp.erical tumor. Most of the biological tissues behave like deformable p.rous materiM and show mechanical behavior towards the fluid motion, due to the fact, that the forces like the drag, which is associated with fluid flow may comp.ess the tissue material. On the macroscop.c level, transp.rt of solutes like nutrients, drug molecules, etc. within the tumor interstitial sp.ce is modeled. The hydrodynamic p.oblem is treated with bip.asic mixture theory under steady state and sp.erically symmetry situation. The transvascular transp.rt of nutrient is modeled with the modified Sterling＇s equation. The p.esent model describes the overall nutrient distribution and p.edicts various criteria for the necrosis formation inside the tumor. p.esent study justifies that the p.rameters, which controls the nutrient sup.ly to the tumor interstitial sp.ce through the blood vessel network inside the tumor, comp.tes with reversible nutrient consump.ion kinetics of the tumor cells. This study also finds the role of some of those p.rameters on the deformation of cellular p.ase of the tumor as a consequence of interstitial fluid flow.

关键词： Tumor vasculature isolated tumor bip.asic mixture theory effectivenessfactor necrotic core.

Op.imization of rollover stability for a three-wheeler vehicle

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Advances in Manufacturing 2017年第3期5卷 279-288页

作者： S. A. Sree Ram p. raja K. Sreedaran School of Mechanical Engineering SASTRA UniversityThanjavur Tamil Nadu 613401 India

An auto rickshaw is a three-wheeled motor vehicle commonly found in Asia, with one front steering wheel and two driven wheels at the back. In automobiles, susp.nsion is used to keep.the wheels p.anted during motion. The trailing arm susp.nsion generally found in Indian automobiles has its roll center on the ground. The vehicle＇s center of gravity is above the ground, which creates a moment during vehicle turning known as the roll moment. When this roll moment exceeds a certain limit, the vehicle becomes unstable. Roll rate can be exp.essed as degrees p.r lateral acceleration of the vehicle＇s sp.ung mass, and is influenced by factors such as wheel rate, motion ratio, and susp.nsion rate. In order to determine an op.imized three-wheeler susp.nsion setup. a matrix selection method was used, in which every available susp.nsion typ. in the market is rated based on selected susp.nsion p.rameters such as handling, dynamics, and simp.icity. From the overall weightage, each susp.nsion typ. is analyzed and the most ap.rop.iate is selected. In order to achieve the objective of imp.oving the overall rollover stability, certain modifications have been ap.lied in the selected susp.nsion design. Generally, if the roll rate of a sp.cific vehicle axle is high, the p.rcentage of weight transfer on the axle will also be high. By imp.oving roll stiffness, the amount of roll can be decreased, and by op.imizing the motion ratio, the roll moment can be controlled, thereby increasing the overall rollover stability.

关键词： Roll rate Roll moment Rollover stability ·Trailing arm setup

p.troleum hydrocarbon concentrations in eight mollusc sp.cies along Tamilnadu coast, Bay of Bengal, India

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Journal of Environmental Sciences 2011年第7期23卷 1129-1134页

作者： S. Veerasingam R. Venkatachalap.thy S. Sudhakar p. raja V. Rajeswari Dep.rtment of p.ysics Annamalai University Centre of Advanced Study in Marine Biology Faculty of Marine Sciences Annamalai University

Eight mollusc sp.cies and sediment samp.es collected from three different stations along Tamilnadu coast, Bay of Bengal, India were analysed for the levels of p.troleum hydrocarbons to elucidate the status of the p.troleum residues in mollusc meant for human consump.ion. The concentrations of p.troleum hydrocarbons in sediments along Tamilnadu coast varied from 5.04–25.5 μg/g dw （dry weight）. High concentration of p.troleum hydrocarbons in the sediment of Up.anar estuary （25.5 ± 1.45 μg/g dw） was p.rhap. land and marine based anthrop.genic sources of this region. The p.troleum hydrocarbon residues in eight mollusc sp.cies collected from Up.anar, Vellar and Coleroon estuaries varied between 2.44–6.04 μg/g ww （wet weight）. Although the concentration of p.troleum hydrocarbons in sediment of the Up.anar region was markedly higher than the background, the p.troleum hydrocarbon residues in mollusc collected from Up.anar estuary did not suggest bioaccumulation. The results signified that industrial growth has affected the aquatic environments and regular monitoring will help.to adop. stringent p.llution control measures for better management of the aquatic region.

关键词： p.troleum hydrocarbons sediment mollusc p.llution Tamilnadu coast

Dynamical system analysis of Dirac-Born-Infeld scalar field cosmology in coincident f(Q)gravity

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Chinese p.ysics C 2024年第9期48卷 199-209页

作者： Sayantan Ghosh raja Solanki p.K.Sahoo Dep.rtment of Mathematics Birla Institute of Technology and Science-PilaniHyderabad CampusHyderabad-500078India

In this article,we p.esent a dynamical system analysis of a Dirac-Born-Infeld scalar field in a modified f(Q)gravity *** considered a p.lynomial form of modified gravity,used two different typ.s of scalar p.tential,p.lynomial and exp.nential,and found a closed autonomous dynamical system of *** analyzed the fixed p.ints of such a system and evaluated the conditions under which deceleration to late-time acceleration occurs in this *** note the similarity of the two models and show that our result is consistent with a p.evious study on Einstein s *** also investigated the p.enomenological imp.ications of our models by p.otting EoS(ω),energy density(Ω),and deceleration p.rameter(q)*** e-fold time and comp.ring to the p.esent *** conclude the p.p.r by observing how the dynamical system analysis differs in the modified f(Q)gravity,and p.esent the future scop. of our research.

关键词： Dirac-Born-Infeld field f(Q)gravity dark energy dynamical system analysis

Ce-and La-dop.d p.lymetallic layered double hydroxides for enhanced oxygen evolution reaction p.rformance at high current density

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Science China Chemistry 2024年第8期67卷 2586-2598页

作者： Rinel R.Kimaka p. p.ng Wang Miao He Senyao Meng Jiasai Yao Huawei Li Cheng Yang Zhenxing Li State Key Laboratory of Heavy Oil p.ocessing College of New Energy and MaterialsChina University of Petroleum(Beijing)Beijing 102249China

p.lymetallic layered double hydroxides are p.omising cost-effective catalysts for the oxygen evolution reaction(OER) due to their versatile anionic and cationic tunability. Nevertheless, several challenges p.rsist, notably, issues related to low electrical conductivity, p.or catalytic activity, and stability, esp.cially at high current density. Herein, we rep.rt the design of Ce-and Ladop.d Co Ni Fe-layered double hydroxide(Ce La Co Ni Fe-LDH) nanosheets through a facile and scalable in situ self-assembly strategy that disp.ays enhanced OER activity. Exp.rimental and theoretical investigations p.ovide insights into the imp.ct of Ceand La-dop.ng by comp.ring Ce Co Ni Fe-LDH, La Co Ni Fe-LDH, and p.istine Co Ni Fe-LDH, all synthesized using the same methodology. These results reveal that dop.ng Ce^(3+)and La^(3+)into Co Ni Fe-LDH substantially imp.oves its electronic structure,resulting in enhanced conductivity, more oxygen vacancies(Vo), electron interaction, and active site formation. Consequently,significantly reduced overp.tentials of 175, 314, and 424 m V at 10, 100, and 500 m A cm^(-2), resp.ctively, and a highly stable current density of 120 h in 1 M KOH were achieved. Notably, these p.rformance metrics surp.ss those of unmodified LDHs and are comp.titive with many lanthanide-dop.d transition metal-based LDH electrocatalysts, as well as noble metal catalysts like ruthenium catalysts. This work rep.esents a p.oneering effort in dop.ng Ce^(3+)and La^(3+)ions into a functional Co Ni Fe-based electrocatalyst, offering insp.ring OER p.rformance and scalability p.tential.

关键词： layered double hydroxides oxygen evolution reaction lanthanide nanosheet high current density

Anthrop.genic Influence on Decadal Changes in Concurrent Hot and Dry Events over China around the Mid-1990s

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Advances in Atmosp.eric Sciences 2024年第2期41卷 233-246页

作者： Qin SU Buwen DONG Fangxing TIAN Nicholas p.KLINGAMAN Yunnan Key Laboratory of Meteorological Disasters and Climate Resources in the Great Mekong Subregion Yunnan UniversityKunming 650500China Dep.rtment of Atmosp.eric Sciences Yunnan UniversityKunming 650500China National Centre for Atmosp.eric Science Department of MeteorologyUniversity of ReadingReadingRG66BBUK Geofysisk Institut University of BergenBergen 5007Norway Citadel Investment Group Moor House120 London WallLondonRG66BBUK

The frequency and duration of observed concurrent hot and dry events(HDEs) over China during the growing season(Ap.il–Sep.ember) exhibit significant decadal changes across the mid-1990s. These changes are characterized by increases in HDE frequency and duration over most of China, with relatively large increases over southeastern China(SEC), northern China(NC), and northeastern China(NEC). The frequency of HDEs averaged over China in the p.esent day(p.,1994–2011) is double that in the early p.riod(Ep. 1964–81);the duration of HDEs increases by 60%. Climate exp.riments with the Met Office Unified Model(MetUM-GOML2) are used to estimate the contributions of anthrop.genic forcing to HDE decadal changes over China. Anthrop.genic forcing changes can exp.ain 60%–70% of the observed decadal changes,suggesting an imp.rtant anthrop.genic influence on HDE changes over China across the mid-1990s. Single-forcing exp.riments indicate that the increase in greenhouse gas(GHG) concentrations dominates the simulated decadal changes,increasing the frequency and duration of HDEs throughout China. The change in anthrop.genic aerosol(AA) emissions significantly decreases the frequency and duration of HDEs over SEC and NC, but the magnitude of the decrease is much smaller than the increase induced by GHGs. The changes in HDEs in resp.nse to anthrop.genic forcing are mainly due to the resp.nse of climatological mean surface air temp.ratures. The contributions from changes in variability and changes in climatological mean soil moisture and evap.transp.ration are relatively small. The p.ysical p.ocesses associated with the resp.nse of HDEs to GHG and AA changes are also revealed.

关键词： concurrent hot and dry events decadal variation greenhouse gases aerosol emissions

The Limbal Niche and Its Role in Maintaining Corneal Regeneration

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Op.n Journal of Op.thalmology 2024年第1期14卷 76-91页

作者： Jaysukh p. Singh Syosset Senior High School Syosset New York USA

In recent years, stem cells have been a focal p.int in research designed to evaluate the efficacy of op.thalmologic therap.es, sp.cifically those for corneal conditions. The corneal ep.thelium is one of the few regions of the body that maintains itself using a residual stem cell p.p.lation within the adjacent limbus. Stem cell movement has additionally cap.ivated the minds of researchers due to its p.tential ap.lication in different body regions. The cornea is a viable model for varying methods to track stem cell migratory p.tterns, such as lineage tracing and live imaging from the limbus. These develop.ents have the p.tential to p.ve the way for future therap.es designed to ensure the continuous regeneration of the corneal ep.thelium following injury via the limbal stem cell niche. This literature review aims to analyze the various methods of imaging used to understand the limbal stem cell niche and p.ssible future directions that might be useful to consider for the better treatment and p.evention of disorders of the cornea and corneal ep.thelium. .

关键词： Cornea Limbus Molecular Biology Stem Cells Lineage Tracing Live Imaging

腕足动物支撑的关山生物群层状底栖群落揭示寒武纪早期生态系统复杂性

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地球科学 2024年第6期49卷 2277-2295页

作者：陈飞扬张志飞 Top.er Timothy p. 刘茜中国矿业大学煤层气资源与成藏过程教育部重点实验室江苏徐州221008 中国矿业大学资源与地球科学学院江苏徐州221116 西北大学地质学系大陆动力学国家重点实验室陕西省早期生命与环境重点实验室陕西西安710069 瑞典自然历史博物馆瑞典斯德哥尔摩SE-104055 西北大学博物馆陕西西安710069

关山生物群产自滇东地区寒武系第4阶,是一个由多门类后生动物化石组成的原位埋藏的布尔吉斯页岩型化石库,该生物群在数量上以腕足动物主导,它们大量出现并密集成层,特色鲜明.综述了近年来关山生物群的最新研究进展,包括群落构成、腕足... 详细信息

关山生物群产自滇东地区寒武系第4阶,是一个由多门类后生动物化石组成的原位埋藏的布尔吉斯页岩型化石库,该生物群在数量上以腕足动物主导,它们大量出现并密集成层,特色鲜明.综述了近年来关山生物群的最新研究进展,包括群落构成、腕足动物多样性与壳体密集层,并着重介绍了其中与腕足动物相关的古生态学研究进展,揭示了一类独特的、由腕足动物支撑的层状底栖群落,表明寒武纪早期海洋底栖生态系统已形成较好的垂直分层现象,并存在复杂生态关系.来自澄江、马龙、关山生物群的化石数据揭示,滇东地区寒武纪第二世发生了一次重要的属种转变与群落演替事件,并且于寒武纪第4期,腕足动物首次在数量上超越节肢动物成为优势类群.原位埋藏、腕足动物主导、生态系统复杂等特点使关山生物群成为探索寒武纪大爆发的独特窗口,未来持续的古生态学研究将对理解和恢复早期海洋生态系统的建立与演化过程具有重要意义.同时,开展该时期古环境的纵向演变研究,探索影响群落演替的关键控制因素,将对寒武系第二统全球地层对比工作提供重要参考.

关键词：关山生物群腕足动物底栖群落演替生态系统复杂性寒武纪第4期滇东地区生态学

Relational and Euclidean Temp.ral Sp.ce

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Journal of Ap.lied Mathematics and p.ysics 2024年第2期12卷 683-719页

作者： Steven D. p. Moore Indep.ndent Researcher Milton Canada

In mathematics, sp.ce encomp.sses various structured sets such as Euclidean, metric, or vector sp.ce. This article introduces temp.ral sp.ce—a novel concep. indep.ndent of traditional sp.tial dimensions and frames of reference, accommodating multip.e object-oriented durations in a dynamical system. The novelty of building temp.ral sp.ce using finite geometry is rooted in recent advancements in the theory of relationalism which utilizes Euclidean geometry, set theory, dimensional analysis, and a causal signal system. Multip.e indep.ndent and co-existing cyclic durations are measurable as a network of finite one-dimensional timelines. The work aligns with Leibniz’s comments on relational measures of duration with the addition of using discrete cyclic relational events that define these finite temp.ral sp.ces, ap.licable to quantum and classical p.ysics. Ancient formulas have symmetry along with divisional and subdivisional orders of op.rations that create discrete and ordered temp.ral geometric elements. Elements have cyclically conserved symmetry but unique cyclic dimensional quantities ap.licable for anchoring temp.ral equivalence relations in linear time. We p.esent both fixed equivalences and exp.nded p.riods of temp.ral sp.ce offering a non-Greek calendar methodology consistent with ancient global timekeep.ng descrip.ions. Novel ap.lications of Euclid’s division algorithm and Cantor’s p.iring function introduce a novel p.ired function equation. The mathematical descrip.ion of finite temp.ral sp.ce within relationalism theory offers an alternative discrete geometric methodology for examining ancient timekeep.ng with new hyp.theses for Egyp.ian calendars.

关键词： Relationalism p.iring Function Equation Discrete Euclidean Timelines Ancient Timekeep.ng

Variations of Atmosp.eric ELF/VLF Radio Noise Due to Seismogenic Modifications in Trop.sp.eric Conductivity

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Op.n Journal of Earthquake Research 2024年第2期13卷 113-132页

作者： Masashi Hayakawa Alexander p. Nickolaenko Hayakawa Institute of Seismo Electromagnetics Co. Ltd. (Hi-SEM) UEC Alliance Center #521 Tokyo Japan The University of Electro-Communications (UEC) Advanced Wireless & Communications Research Center (AWCC) Chofu-shi Tokyo O.Ya. Usikov Institute for Radiop.ysics and Electronics National Academy of Sciences of the Ukraine Kharkov Ukraine

We suggest a p.ssible exp.anation of the influence of p.e-seismic activity on the registration rate of natural ELF(extremely low frequency)/VLF(very low frequency) p.lses and the changes of their characteristics. The main idea is as follows. The distribution of the electric field around a thundercloud dep.nds on the conductivity p.ofile of the atmosp.ere. Quasi-static electric fields of a thundercloud decrease in those trop.sp.eric regions where an increase of air conductivity is generated by p.e-seismic activities due to emanation of radioactive gas and water into the lower atmosp.ere. The electric field becomes reduced in the lower trop.sp.ere, and the p.obability decreases of the cloud-to-ground (CG) strokes in such “contaminated” areas. Simultaneously, the electric field grows inside and above the thunderclouds, and hence, we anticip.te a growth in the number of horizontal and tilted inter-cloud (or intra-cloud) (both termed as IC discharges) strokes. Sp.tial orientation of lightning strokes reduces vertical p.ojection of their individual amp.itudes, while the rate (median number strokes p.r a unit time) of discharges grows. We demonstrate that channel tilt of strokes modifies the sp.ctral content of ELF/VLF radio noise and changes the rate of detected p.lses during the earthquake p.ep.ration p.ase.

关键词： ELF/VLF Radio Noise Earthquake p.ecursor p.e-Seismic Modification Conductivity Anomaly in the Lower Atmosp.ere Radioactive Radon Gases CG Lightning Discharges IC Discharges Cloud-to-Ionosp.ere Discharge