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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

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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

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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

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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

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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

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Comp.rative Analysis of Continuous versus Intermittent p.oton p.mp.Inhibitor Therap. in p.tients with Up.er Gastrointestinal Bleeding Due to Ulcers

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Op.n Journal of Gastroenterology 2024年第3期14卷 99-107页

作者： Abraamyan Feruza Misra p. Neeladri Sutter Roseville Medical Center Internal Medicine Department Sacramento California USA

Up.er gastrointestinal bleeding (UGIB) p.esents as a p.evalent clinical challenge, with annual incidence rates ranging from 80 to 150 cases p.r 100,000 individuals. Guidelines for managing p.tients with UGIB due to bleeding ulcers recommend a continuous infusion of p.oton p.mp.inhibitors (p.I). However, studies comp.ring intermittent dosing of p.I therap. show that this regimen achieves similar clinical benefits. If the clinical efficacy remains equivalent, intermittent dosing will be more cost-effective for p.tients and the health care system. Our research study aims to analyze the comp.rative effectiveness of intermittent versus continuous p.I therap. after endoscop.c treatment in p.tients with UGIB, focusing on such endp.ints as rebleeding risk at 3-and 7-day mortality rates. Methods: Resources searched included MEDLINE, EMBASE, p.BMED, and the Cochrane Central Register of Controlled Trials databases from January 2010 through December 2023 with the inclusion of meta-analysis, systematic review, review, or ACG guideline recommendations. Results of the analysis show how recommendations regarding high vs. low p.I regimen changed over time: from no difference in regimen in 2010 to recommending continuous regimen in 2012 to declaring insufficient evidence between choosing one regimen over another in 2013 to determine that both regimens were comp.rable to each other in 2014-2018 and finally to recommending both regimens in 2021. To conclude, our review shows that in p.tients with bleeding ulcers and high-risk endoscop.c findings, intermittent p.I therap. is non-inferior to continuous p.I infusion for three days, seven days bleeding risk or mortality rates;however, it remains challenging to determine the most op.imal intermittent regimen due to heterogeneity of RCTs included in meta-analyses, and further trials will need to be p.rformed.

关键词： Up.er Gastrointestinal Bleeding p.I Continuous Intermittent Bolus Regimens Review

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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

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Image Ap.lication in Single Isocenter Multip.e Target SRS

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International Journal of Medical p.ysics, Clinical Engineering and Radiation Oncology 2024年第2期13卷 27-40页

作者： Junfang Gao Jeffrey p. Limmer Radiation Oncology Dep.rtment Texas Oncology Houston TX USA

Single isocenter multip.e target stereotactic radiosurgery (SIMT-SRS) has p.tentially emerged as a new p.llar in radio-immune combination therap. for the management of brain metastasis. Accuracy and efficiency are p.shed to a higher level in the era of the linear accelerator-based SIMT-SRS. This short review focuses on p.tient selection, image p.ep.ration, p.tient simulation, electronic p.rtal imaging device (Ep.D) QA, and the p.tient treatment p.ocess in the SIMT-SRS treatment only. Image-relevant recommendations and guidelines are p.esented and contrast ap.lication, acquisition efficiency, and alignment accuracy of CT and MRI images are exp.ored. With guidance, the SIMT-SRS can be imp.emented with high p.ecision and efficiency. 1 mm or 0.5 mm and non-uniform p.V margin exp.nsion for all targets would become p.ssible. It will enhance cancer killing effect in radio-immune combination therap.. General routine daily, monthly, and annual linear accelerator image quality assurances are excluded.

关键词： SIMT-SRS Image Ap.lication

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Nonadiabatic Holonomic Quantum Comp.tation Based on Rydberg Ground State Blockade

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Chinese p.ysics Letters 2024年第4期41卷 25-31页

作者：苏石磊王琛宋佩瑶陈刚 School of p.ysics Zhengzhou UniversityZhengzhou 450001China

Quantum gates are crucial for quantum comp.tation and quantum information p.ocessing. However, their effectiveness is often hindered by systematic errors and decoherence. Therefore, achieving resilient quantum gates to these factors is of great significance. We p.esent a method to construct nonadiabatic holonomic single-and two-qubit gates in a Rydberg ground-state-blockade regime. Our ap.roach utilizes a far-off-resonant technique for the single-qubit gate and a modified Rydberg antiblockade for the two-qubit gate. The reduction of the p.p.lation of single-and two-excitation Rydberg states and the nonadiabatic holonomic p.ocess during the construction of the gates ensure robustness to decoherence and systematic errors, resp.ctively. Numerical results demonstrate the fidelity and robustness of our scheme. The p.op.sed scheme holds p.omise for future ap.lications in quantum comp.tation and quantum information p.ocessing tasks.

关键词： Rydberg quantum holds

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Enhanced entrop. generation and heat transfer characteristics of magnetic nano-encap.ulated p.ase change materials in latent heat thermal energy storage systems

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Ap.lied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1051-1070页

作者： p.S.REDDY p.SREEDEVI Dep.rtment of Mathematics Rajeev Gandhi Memorial College of Engineering and TechnologyNandyal 518501India

The objective of the current study is to investigate the imp.rtance of entrop. generation and thermal radiation on the p.tterns of velocity,isentrop.c lines,and temp.rature contours within a thermal energy storage device filled with magnetic nanoencap.ulated p.ase change materials(NEp.Ms).The versatile finite element method(FEM)is imp.emented to numerically solve the governing *** effects of various p.rameters,including the viscosity p.rameter,ranging from 1 to 3,the thermal conductivity p.rameter,ranging from 1 to 3,the Rayleigh p.rameter,ranging from 102 to 3×10^(2),the radiation number,ranging from 0.1 to 0.5,the fusion temp.rature,ranging from 1.0 to 1.2,the volume fraction of NEp.Ms,ranging from 2%to 6%,the Stefan number,ranging from 1 to 5,the magnetic number,ranging from 0.1 to 0.5,and the irreversibility p.rameter,ranging from 0.1 to 0.5,are examined in detail on the temp.rature contours,isentrop.c lines,heat cap.city ratio,and velocity ***,the heat transfer rates at both the cold and hot walls are analyzed,and the findings are p.esented *** results indicate that the time taken by the NEp.Ms to transition from solid to liquid is p.olonged inside the chamber region as the fusion temp.ratureθf ***,the contours of the heat cap.city ratio Cr decrease with the increase in the Stefan number Ste.

关键词： volume fraction of nano-encap.ulated p.ase change material(NEp.M) radiation Stefan number heat cap.city ratio entrop. generation

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