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Creation of an oxygen-enriched environment during synthesis as an effective way to improve luminescent properties of Y_(2)O_(3):Eu^(3+)

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Journal of Rare Earths 2025年第1期43卷 21-29,I0001页

作者： Aleksandr A.Nashivochnikov Anton I.Kostyukov mariana I.Rakhmanova Lidiya S.Kibis Svetlana v.Cherepanova Evgenii A.Suprun Novosibirsk State University Pirogova Str.2630090NovosibirskRussia Boreskov Institute of Catalysis SB RAS 5 Lavrentiev Ave630090NovosibirskRussia Nikolaev Institute of Inorganic Chemistry SB RAS 3 Lavrentiev Ave630090NovosibirskRussia

The growing demand for luminescent nanomaterials intended for various applications increases the necessity to develop and improve approaches to the creation of highly efficient nanosized *** current study,an approach to enhancing the efficiency of red luminescence of monoclinic Y_(2)O_(3):Eu^(3+)with the particle size of~20 nm by creating the oxygen-enriched environment during the gas-phase synthesis was *** investigate the effect of oxygen amount during the synthesis on characteristics of the phosphor,a series of nano structured Y_(2)O_(3):Eu^(3+)with the addition of 0-40 vol%O_(2) to the main buffer gas Ar was synthesized by laser *** is shown that the amount of added O_(2) exerts virtually no effect on the phase composition and particle size,but significantly improves the luminescent characteristics of Y_(2)O_(3):Eu^(3+).Thus,the addition of 30 vol%O_(2) leads to virtually a 20-fold growth in the photoluminescence(PL)intensity caused by ^(5)D_(0)→^(7)F_(0-4) transitions in Eu^(3+)and an increase in the absolute PL quantum yield from 3%to 53%(λex=395 nm)compared to the sample synthesized without O_(2).The addition of oxygen also improves the emission color coordinates from(0.571,0.320)to(0.630,0.322)due to the removal of a considerable fraction of oxygen *** synthesized nanopowders are shown to be highly stable:upon storage under ambient conditions for two *** yield(QY)of the samples decreases by less than 2%.It is expected that the key features underlying the proposed approach will be useful for various methods used to synthesize oxide nanophosphors.

关键词： Photoluminescence Quantum yield Laservaporization Y_(2)0_(3):Eu^(3+) monoclinic Y_(2)0_(3) Rareearths

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Role of Helicobacter pylori infection and the risk of cholelithiasis

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World Journal of Gastroenterology 2025年第8期31卷 152-154页

作者： Nicolò Fabbri Salvatore Greco Antonio Pesce Francesco virgilio Danila Romeo Carlo v Feo Unit of General Surgery Local Health Agency of FerraraFerrara 44100Emilia-RomagnaItaly Unit of Internal medicine Local Health Agency of FerraraFerrara 44100Emilia-RomagnaItaly Department of morphology Surgeryand Experimental MedicineUniversity of FerraraFerrara 44100Emilia-RomagnaItaly Unit of Hepato-Biliary Surgery IRCCS San Raffaele HospitalMilan 20132LombardyItaly Local Health Agency of Ferrara Ferrara 44100Emilia-RomagnaItaly

This article aims to deepen the understanding of the role of Helicobacter pylori(***)infection in the development of cholelithiasis,initiated by the article by Yao et al,who investigated the potential link between *** infection and the development of cholelithiasis through a multicenter retrospective study on an Asian population of over 70000 *** also performed a compre-hensive analysis of previously published studies on *** and cholelithiasis,finding a positive association therein[odds ratio(OR)=1.103,P=0.049].Patients positive for *** also had lower levels of total and direct bilirubin,but higher levels of total cholesterol and low-density lipoprotein cholesterol compared to uninfected patients(Pve confirmed that *** is a risk factor for cholelithiasis(Pve shown a positive association between *** and cholelithiasis in Asia(OR=1.599,P=0.034),but not in Europe(OR=1.277,P=0.246).moreover,*** appears to be related to a higher ratio of choledocho-lithiasis/cholecystolithiasis(OR=3.321,P=0.033).The authors conclude that *** infection is positively correlated with cholelithiasis,particularly with the choledocholithiasis phenotype,especially in Asia,and it is potentially related to bilirubin and cholesterol metabolism.

关键词： Helicobacter pylori Helicobacter pylori infection Cholelithiasis Proton pump inhibitors Choledocholithiasis

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Links of Terrestrial Environment with Solar Activity and Solar and Planetary Orbital motion

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Atmospheric and Climate Sciences 2025年第1期15卷 72-105页

作者： valentina v. Zharkova Irina vasilieva Department of mPEE Faculty of Engineering and Environment University of Northumbria Newcastle upon Tyne UK ZvS Research Enterprise Ltd. London UK Department of Solar Physics Main Astronomical Observatory Kyiv Ukraine

In this paper we emphasize statistical links between solar activity and orbital motion with various terrestrial phenomena: terrestrial temperature, sea levels, ice areas, frequencies of volcanic eruptions, and Oceanic Nino Index (ONI). Solar activity links. The solar activity indices are expressed through the averaged sunspot numbers SSN and the summary curve of eigen vectors of the solar background magnetic field (SBmF). The terrestrial temperature (GLB dataset), global sea level, and volcanic eruption frequencies are shown from the wavelet analysis to have a clear link to the SBmF index, which has the same significant period of 21.4 years. The ice and snow areas in the Northern hemisphere are found to vary with a period of 10.7 years equal to the usual sunspot activity cycle while in the Southern hemispheres, no links to solar activity are detected. Solar orbital motion links. The variations of total solar irradiance (TSI) measured from the abundance of 14C isotope during the Holocene are shown to have a similar period of 2200-2300 years (Hallstatt’s cycle) as the solar inertial motion (SIm) induced by the gravitation of large planets, In the current millennium the amount of TSI deposited on Earth in the march-September to Northern hemisphere is ≈1.2% higher than in the September to march in the Southern hemisphere. The wavelet analysis of ONI revealed the two significant periods of 4.5 and 12 years. The first one is shown to have a link to the lunar perigee period variations while the second period is linked to the Jupiter period of revolution about the Sun whose gravitation seems to trigger terrestrial tectonic processes leading to volcanic eruptions. The ONI variation is noticeably linked to the occurrence of underwater volcanic eruptions (correlation of 25%), which, in turn, are linked to the tidal forces of Jupiter, the moon and the Sun in its inertial motion. Joint effects of the solar activity and the solar and planetary orbital motion are likely to govern

关键词： Terrestrial Temperature Terrestrial Sea Level Terrestrial Ice Areas El Nino Southern Oscillation volcanic Eruptions Underwater volcanic Eruptions Solar magnetic Field Solar Activity Solar Inertial motion Correlation Jupiter Revolution Period Lunar Perigee Period

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Four-wave mixing in a laser diode gain medium induced by the feedback from a high-Q microring resonator

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Photonics Research 2025年第1期13卷 59-68页

作者： DARIA m.SOKOL NIKITA YU DmITRIEv DmITRY A.CHERmOSHENTSEv SERGEY N.KOPTYAEv ANATOLY v.mASALOv vALERY E.LOBANOv IGOR A.BILENKO ARTEm E.SHITIKOv Russian Quantum Center moscow Institute of Physics and Technology (mIPT) Skolkovo Institute of Science and Technology Lebedev Physical Institute Russian Academy of Sciences Faculty of Physics M.V.Lomonosov Moscow State University

Laser diodes are widely used and play a crucial role in myriad modern applications including nonlinear optics and ***,we explore the four-wave mixing effect in a laser diode gain medium induced by the feedback from the high-Q microring *** phenomenon can be observed at a laser frequency scan close to the microresonator eigenfrequency,prior to the transition of the laser diode from a free-running to a self-injection locking *** effect opens up the possibility for generation of remarkably low-noise,stable,and adjustable microwave *** provide a detailed numerical study of this phenomenon proven with experimental results and demonstrate the generation of the signals in the GHz *** obtained results reveal the stability of such regime and disclose the parameter ranges enabling to achieve ***,our findings uncover,to our knowledge,a novel laser diode operation regime and pave the way for the creation of new types of chip-scale,low-noise microwave sources,which are highly demanded for diverse applications,including telecommunication,metrology,and sensing.

关键词： Four wave mixing

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Probing multi-mobility edges in quasiperiodic mosaic lattices

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Science Bulletin 2025年第1期70卷 58-63页

作者： Jun Gao Ivan m.Khaymovich Xiao-Wei Wang Ze-Sheng Xu Adrian Iovan Govind Krishna Jiayidaer Jieensi Andrea Cataldo Alexander v.Balatsky val Zwiller Ali W.Elshaari Department of Applied Physics KTH Royal Institute of TechnologyAlbanova University CentreStockholm SE-10691Sweden Nordita Stockholm University and KTH Royal Institute of TechnologyStockholm SE-10691Sweden Institute for Physics of microstructures Russian Academy of SciencesNizhny Novgorod 603950Russia Center for Integrated Quantum Information Technologies(IQIT) School of Physics and Astronomy and State Key Laboratory of Advanced Optical Communication Systems and NetworksShanghai Jiao Tong UniversityShanghai 200240China Department of Physics University of ConnecticutStorrsConnecticut 06269USA

The mobility edge(mE)is a crucial concept in understanding localization physics,marking the critical transition between extended and localized states in the energy *** localization scaling theory predicts the absence of mE in lower dimensional ***,the search for exact mEs,particularly for single particles in lower dimensions,has recently garnered significant interest in both theoretical and experimental studies,resulting in notable ***,several open questions remain,including the possibility of a single system exhibiting multiple mEs and the continual existence of extended states,even within the strong disorder ***,we provide experimental evidence to address these questions by utilizing a quasiperiodic mosaic lattice with meticulously designed nanophotonic *** observations demonstrate the coexistence of both extended and localized states in lattices with broken duality symmetry and varying modulation *** single-site injection and scanning the disorder level,we could approximately probe the mE of the modulated *** results corroborate recent theoretical predictions,introduce a new avenue for investigating mE physics,and offer inspiration for further exploration of mE physics in the quantum regime using hybrid integrated photonic devices.

关键词： mobility edge Localization physics mosaic lattice Nanophotonics

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A Cost-Effective Flood Warning System for Small Urban Basins

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Journal of Earth Science 2025年第1期36卷 307-313页

作者： Robert E.Criss Eric m.Stein Department of Earth and Planetary Sciences Washington UniversitySt.Louis MO 63130USA

An effective warning system for flash floods along the upper River des Peres, a small urban stream in eastern missouri, USA, is based on three enterprise-level, automated rain *** floods in this 25 km~2 basin develop rapidly and are commonly caused by small but intense thunderstorm cells, these rain gauges were necessarily deployed within the watershed, and immediate telemetry and processing of rainfall delivered in 5-minute intervals is required. Available data show that damaging floods in this area occur only 30 min to 3 h following the delivery of 38 mm of rainfall or more in a single hour. Water levels along this stream can rise more than 3 m/h. Since full deployment in Nov. 2021, our system has successfully predicted 3 significant floods with one false positive.

关键词： urban floods flood warning water levels hydrology

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mossbauer,optical and structural properties of Fe^(3+) ion in borate glass

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Journal of Rare Earths 2025年第1期43卷 162-170,I0006页

作者： Essam A.Elkelany Hesham Y.Amin A.Samir m.m.EL-Hady H.H.El-Bahnasawy moukhtar A.Hassan Basic Science Department Faculty of EngineeringSinai UniversityAl-Arish45511Egypt School of Information and Electrical Engineering Hangzhou City UniversityHangzhou30015China State Key Laboratory of modern Optical Instrumentation College of Optical Science and EngineeringZhejiang UniversityHangzhou310027China Basic Science Department Faculty of Engineering at ShoubraBenha University11629Egypt Physics Department Faculty of ScienceAl-Azhar University11884CairoEgypt

Lanthanum-bearing iron lithium borate glass is a quaternary system for oxide glasses and was prepared via the melt-quenching *** present article correlates the structure,optical,ligand field and m?ssbauer data on iron lithium borate glass co ntaining La^(3+).The density was measured,while the molar volume was *** physical parameters are *** increasing the La_(2)O_(3) content within the glass network,infrared spectra analysis reveals structural modifications such as the increase in BO_(4) units and the decline in both BO_(3) units and NBO bonds ***,optical absorption spectra were *** absorption spectra disclose a plethora of electronic transitions that are related to Fe^(3+)in tetrahedral and octahedral sites,however,Fe^(2+)phase is not observed in optical spectra,but it has a clear signature in m?ssbauer ***,the glass absorption edges undergo a clear blue shift,reflecting an increased band gap energy(1.96-2.28 ev).The decline in NBO bonds justifies this ***,the values of crystal field splitting are increased,while the values of Racah parameters are *** trend is justified by the decline in NBO bonds and increases electron localization around Fe cations.m?ssbauer spectra confirm the existence of Fe^(3+)in tetrahedral and octahedral sites,while Fe^(2+)exists in only a tetrahedral *** increasing La_(2)O_(3) content,the isomer shift of Fe^(3+)in tetrahedral sites changes to be 0.312-0.329 mm/s,while the isomer shift of octahedral Fe^(3+)is 0.424-0.456 mm/*** findings coincide with optical *** the isomer shift of tetrahedral Fe^(2+)is 0.902-0.911 mm/*** results of structural,optical and ligand field associated with m?ssbauer spectra open more vistas toward the utility of these samples in the optics realm.

关键词： Fe3+ions Rare-earth oxide mossbauer spectra Ligand field parameters Optical properties

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Glia-to-neuron reprogramming to the rescue?

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Neural Regeneration Research 2025年第5期20卷 1395-1396页

作者： Jack W.Hickmott Cindi m.morshead Department of Surgery University of TorontoTorontoONCanada Donnelly Centre for Cellular and Biomolecular Research TorontoONCanada Institute of Biomedical Engineering University of TorontoTorontoONCanada The KITE Research Institute Toronto Rehabilitation InstituteUniversity Health NetworkTorontoONCanada

Over the last two decades,the dogma that cell fate is immutable has been increasingly challenged,with important implications for regenerative *** brea kth rough discovery that induced pluripotent stem cells could be generated from adult mouse fibroblasts is powerful proof that cell fate can be *** exciting extension of the discovery of cell fate impermanence is the direct cellular reprogram ming hypothesis-that terminally differentiated cells can be reprogrammed into other adult cell fates without first passing through a stem cell state.

关键词： programming passing proof

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Dendritic spine degeneration:a primary mechanism in the aging process

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Neural Regeneration Research 2025年第6期20卷 1696-1698页

作者： Gonzalo Flores Leonardo Aguilar-Hernández Fernado García-Dolores Humberto Nicolini Andrea Judith vázquez-Hernández Hiram Tendilla-Beltrán Instituto de Fisiología Benemérita Universidad Autónoma de Puebla(BUAP)PueblaMexico Instituto de Ciencias Forenses(INCIFO) Tribunal Superior de Justicia de la Ciudad de México(TSJCDMX).Mexico CityMexico Instituto Nacional de medicina Genómica(INmEGEN) Mexico CityMexico

Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a wide range of factors, spanning from genetic to environmental factors, and even includes the gut microbiome(Gm)(mayer et al., 2022). All these processes coincide at some point in the inflammatory process, oxidative stress, and apoptosis, at different degrees in various organs and systems that constitute a living organism(mayer et al., 2022;AguilarHernández et al., 2023).

关键词： aging process stress

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Influence of quasi-electrostatic support on amplification of space charge waves in amplification section of a superheterodyne free electron laser

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Chinese Physics B 2025年第1期34卷 308-313页

作者： A.v.Lysenko S.S.Ilin Sumy State University 116Kharkivska st.40007 SumyUkraine

A theoretical study of the influence of a quasi-electrostatic support on the amplification level of the slow space charge wave(SCW) in the amplification section of a superheterodyne free electron laser(FEL) was carried out. One of the ways to significantly increase the saturation level of the slow SCW is maintaining the conditions of a three-wave parametric resonance between the slow, fast SCWs and the resulting pump electric field. This can be done by introducing the quasielectrostatic support in the superheterodyne FEL amplification section. Also, it was found that the generated pump electric field significantly influences the maintenance of parametric resonance conditions. As a result, this increases the saturation level of the slow SCW by 70%. Finally, the quasi-electrostatic support significantly reduces the maximum value of the electrostatic undulator pump field strength, which is necessary to achieve the maximum saturation level of the slow SCW.

关键词： superheterodyne free-electron lasers space charge waves electrostatic undulator quasielectrostatic support

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