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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

Arctic sea-ice extent: No record minimum in 2023 or recent years

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 52-55页

作者： Ola M.Johannessen Tor i.Olaussen Nansen Scientific Society BergenNorway Nansen Environmental and Remote Sensing Center BergenNorway

Arctic sea-ice extent reaches its minimum each year in September. On 11 September 2023 the minimum was 4.969 million square kilometers(***^(2)). This was not a record low, which occurred in 2012, when the minimum was 4.175 ***^(2), 0.794 ***^(2) less than the minimum in 2023. However, the ice extent had decreased by 0.432 ***^(2) compared with 2022. Nevertheless, the summer melting in 2023 was remarkably less than expected when considering the strong heat waves in the atmosphere and ocean, with record temperatures set around the world. in general, there is a high correlation between the long-term decrease in sea-ice extent and the increasing CO_(2) in the atmosphere, where the increase of CO_(2) in recent decades explains about 80% of the decrease in sea ice in September, while the remainder is caused by natural variability.

关键词： Sea ice Arctic Minimum ice Climate

Bacteria and host: what does this mean for sepsis bottleneck?

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World Journal of Emergency Medicine 2025年第1期16卷 10-17页

作者： Azzah S Alharbi Raghad Hassan Sanyi Esam i Azhar Department of Clinical Microbiology and immunology Faculty of MedicineKing Abdulaziz UniversityJeddah 21362Saudi Arabia Special infectious Agent Unit King Fahad Medical Research CenterKing Abdulaziz UniversityJeddah 21362Saudi Arabia College of Health and Medical Technology Middle Technical UniversityBaghdad 10047Iraq Department of Medical Laboratory Sciences Faculty of Applied Medical SciencesKing Abdulaziz UniversityJeddah 21362Saudi Arabia

BACKGROUND: Sepsis is a life-threatening inflammatory condition in which the invading pathogen avoids the host's defense mechanisms and continuously stimulates and damages host cells. Consequently, many immune responses initially triggered for protection become harmful because of the failure to restore homeostasis, resulting in ongoing hyperinflammation and immunosuppression. METHODS: A literature review was conducted to address bacterial sepsis, describe advances in understanding complex immunological reactions, critically assess diagnostic approaches, and emphasize the importance of studying bacterial bottlenecks in the detection and treatment of ***: Diagnosing sepsis via a single laboratory test is not feasible;therefore, multiple key biomarkers are typically monitored, with a focus on trends rather than absolute values. The immediate interpretation of sepsis-associated clinical signs and symptoms, along with the use of specific and sensitive laboratory tests, is crucial for the survival of patients in the early stages. However, long-term mortality associated with sepsis is now recognized, and alongside the progression of this condition, there is an in vivo selection of adapted ***: Bacterial sepsis remains a significant cause of mortality across all ages and societies. While substantial progress has been made in understanding the immunological mechanisms underlying the inflammatory response, there is growing recognition that the ongoing host-pathogen interactions, including the emergence of adapted virulent strains, shape both the acute and long-term outcomes in sepsis. This underscores the urgent need for novel high-throughput diagnostic methods and a shift toward more pre-emptive, rather than reactive, treatment strategies in sepsis care.

关键词： Sepsis Bacteria Bottleneck inflammation

Viscosity, NMR Diffusometry and Light Scattering Data for Aqueous and Aqueous-Salt Solutions of Poly(1-butyl-3-vinylimidazolium bromide)

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CHiNESE JOURNAL OF POLYMER SCiENCE 2025年第2期43卷 380-391页

作者： Korchak, Petr A. Yarchenko, Polina S. Safonova, Evgenia A. Koneva, Alina S. Victorov, Alexey i. St Petersburg State Univ St Petersburg 199034 Russia

Poly(1-butyl-3-vinylimidazolium bromide) is a polymerized ionic liquid (PiLs), a relatively new class of materials that combines the attractive properties of ionic liquids (iLs) and polyelectrolytes and finds wide applications. The backbone of this PiL is composed of quaternary imidazolium salts, which are among the most promising and popular iLs. However, little is known about the physicochemical characteristics of the aqueous solutions of this PiL. in this study, we synthesized and characterized samples of this PiL and obtained experimental data on the viscosity, static and dynamic light scattering, and nuclear magnetic resonance diffusometry for aqueous and aqueous KBr solutions with varying polymer contents at T=298.15 K. We discuss the effects of the polymer concentration and salinity on the behavior of the solution.

关键词： Polymerized ionic liquid Polyelectrolyte solutions Viscosity Light scattering NMR diffusometry

Multisensory mechanisms of gait and balance in Parkinson’s disease:an integrative review

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Neural Regeneration Research 2025年第1期20卷 82-92页

作者： Stiven Roytman Rebecca Paalanen Giulia Carli Uros Marusic Prabesh Kanel Teus van Laar Nico i.Bohnen Department of Radiology University of MichiganAnn ArborMIUSA Department of Neurology University of MichiganAnn ArborMIUSA Morris K.Udall Center of Excellence for Parkinson’s Disease Research University of MichiganAnn ArborMIUSA institute for Kinesiology Research Science and Research Centre KoperKoperSlovenia Department of Health Sciences Alma Mater Europaea–ECMMariborSlovenia Parkinson’s Foundation Research Center of Excellence University of MichiganAnn ArborMIUSA Department of Neurology University of GroningenUniversity Medical Center GroningenGroningenThe Netherlands Neurology Service and GRECC VA Ann Arbor Healthcare SystemAnn ArborMIUSA

Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have on our aging *** and gait control does not happen automatically,as previously believed,but rather requires continuous involvement of central nervous *** effectively exert control over the body,the brain must integrate multiple streams of sensory information,including visual,vestibular,and somatosensory *** mechanisms which underpin the integration of these multisensory signals are the principal topic of the present *** multisensory integration theories focus on how failure of cognitive processes thought to be involved in multisensory integration leads to falls in older *** emphasis,however,has been placed on specific contributions of individual sensory modalities to multisensory integration processes and cross-modal interactions that occur between the sensory modalities in relation to gait and *** the present work,we review the contributions of somatosensory,visual,and vestibular modalities,along with their multisensory intersections to gait and balance in older adults and patients with Parkinson’s *** also review evidence of vestibular contributions to multisensory temporal binding windows,previously shown to be highly pertinent to fall risk in older ***,we relate multisensory vestibular mechanisms to potential neural substrates,both at the level of neurobiology(concerning positron emission tomography imaging)and at the level of electrophysiology(concerning electroencephalography).We hope that this integrative review,drawing influence across multiple subdisciplines of neuroscience,paves the way for novel research directions and therapeutic neuromodulatory approaches,to improve the lives of older adults and patients with neurodegenerative diseases.

关键词： aging balance encephalography functional magnetic resonance imaging gait multisensory integration Parkinson’s disease positron emission tomography somatosensory vestibular visual

Properties of Ball Lightning as a Basis for Creating its Theory

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Journal of Applied Mathematics and Physics 2025年第1期13卷 209-229页

作者： Anatoly i. Nikitin V.L. Talrose institute for Energy Problems of Chemical Physics at N.N. Semenov Federal Research Center for Chemical Physics Russian Academy of Sciences Moscow Russia

Observational data of ball lightning often contradict each other, so it was sometimes proposed to build a theory of ball lightning based on only a small number of statistically reliable observations. Work on this principle did not bring results. The correct approach to creating the theory of ball lightning should be the desire to explain all of its properties, even those that are rare. in the database of ball lightning observations, the most valuable are the cases when it left traces available for quantitative analysis, or was filmed by video cameras. Ball lightning is a material body consisting of a shell and a multi-element core. Cases of water heating made it possible to determine energy density of ball lightning, which turned out to be higher than 1010 J/m3. A study of results of ball lightning explosion, as well as its effect on snow, made it possible to assume that it is capable of generating radiation with a wavelength of about 10 cm, the power of which can be greater than 120 kW. Ball lightning has an electric charge of 10−3 - 10−1 C. The presence of an electric charge explains the complex nature of its movement in atmosphere. Ball lightning is formed under the action of magnetic field pulse and ultraviolet radiation of linear lightning channel. A model of ball lightning in the form of a core of charged “dynamic capacitors” and a shell of polarized water molecules is considered. it is shown that this shell is capable of withstanding the force of Coulomb repulsion of the core charges and the pressure caused by the movement of charge carriers. The glow of ball lightning core occurs due to orbital motion of electrons at a speed close to light speed. The intensity of the glow is determined by the degree of uniformity of electrons arrangement along the orbit.

关键词： Ball Lightning Properties Model Core Shell Dynamic Capacitor

Apolipoprotein A-i binding protein-mediated neuroprotection in glaucomatous neuroinflammation and neurodegeneration

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Neural Regeneration Research 2025年第5期20卷 1414-1415页

作者： Sinwoo Hwang Seunghwan Choi Soo-Ho Choi Keun-Young Kim Yury i.Miller Won-Kyu Ju Hamilton Glaucoma Center and Shiley Eye institute The Viterbi Family Department of OphthalmologyUniversity of California San DiegoLa JollaCAUSA Department of Medicine University of California San DiegoLa JollaCAUSA National Center for Microscopy and imaging Research Department of NeurosciencesUniversity of California San DiegoLa JollaCAUSA

Glaucoma is a multifactorial eye disorder that can cause vision loss and irreversible blindness,affecting individ uals aged 40 to 80 yea rs *** to the aging population,it is expected that the number of people affected by glaucoma will surpass 111 million by 2040 as the disease becomes more *** primarily contributes to optic nerve axon loss and the progressive degeneration of retinal ganglion cells (RGCs),subsequently leading to vision impairment.

关键词： irreversible pass primarily

Nano-Enhanced Dairy Scum Biodiesel Blends:Unleashing the Power of Aluminium Oxide for Sustainable and Efficient Engine Performance

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Journal of Thermal Science 2025年第1期34卷 283-302页

作者： Veeranna MODi Prasad B.RAMPURE Sunil Kumar SHETTY Madeva NAGARAL Channa Keshava NAiK N Johar MGM Muhammad irsyad ABDULLAH Abdullah i.AL-MANSOUR Shamshad ALAM KLE College of Engineering and Technology ChikodiVisvesvaraya Technological UniversityBelagavi 590018KarnatakaIndia Nitte(Deemed to be University) NMAM Institute of Technology(NMAMIT)Department of Mechanical EngineeringNitte 574110India Aircraft Research and Design Centre HALBangalore 560037KarnatakaIndia Department of Mechanical Engineering BGS College of Engineering and TechnologyBengaluruAffiliated to Visvesvaraya Technological UniversityBelagaviIndia Management and Science University Selangor Darul EhsanMalaysia Department of Civil Engineering College of EngineeringKing Saud UniversityRiyadh-11421Saudi Arabia

This study investigates the effect of aluminium oxide nanoparticlesaddition to biodiesel blends made from dairy milk scum on performance and combustion characteristics of the diesel *** dispersion of Al_(2)O_(3)nanoparticles in B20 blends at different concentrations was done with the help of *** number of blends were prepared for the *** Machine learning algorithms(Random Forest(RF)and CatBoost)was used for the *** results show that in comparison to biodiesel blends without nanoparticles,the kinematic viscosity and density is higher for fuel blends with *** these Fuel blends have higher calorific *** blends exhibited reduced Brake Specific Fuel Consumption(BSFC)of 2.85% than the blends without nano particles(Dairy Scum Methyl Ester Biodiesel 20%+Neat Diesel 80%(in volume),DSMEB20),57.14%less CO,40.8% less hydrocarbon,and increased NO_(x)emissions compared to conventional diesel,contributing to the development of environmentally friendly and renewable biofuel blends with *** B20NP30 is the optimal blend for performance and emission *** study concludes with findings on enhanced Brake Thermal Efficiency(BTE)of 26.29% in 3×10^(-5)(in volume)Al_(2)O_(3)nanoparticle-blended DSME B20 and other DSME B20 fuel blends,emphasizing the importance of optimal nanoparticle *** correlation matrix shows how engine load,efficiency measures(BTE,BSFC),and emissions(CO,CO_(2),NO_(x),Smoke)are connected in complex *** results help us understand the complicated dynamics of engine performance and emission characteristics ***'s diagram for BTE and BSFC shows that CatBoost-based BTE models perform superior to RF-based models during the training as well as testing *** results were obtained for CO and CO_(2)emission results.

关键词： Dairy Scum Methyl Ester Biodiesel Ci engine Al_(2)O_(3)concentration

Coarse to Fine: The Role of Severe Plastic Deformation in Advancing Titanium-Based Medical implants - A Comprehensive Review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 295-306页

作者： Dragana R Mihajlović Bojan i Međo ivana Lj Cvijović-Alagić Veljko R Djokić Faculty of Technology and Metallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia Vinča institute of Nuclear Sci-ences-National institute of the Republic of Serbia University of Belgrade11001BeogradSerbia innovation Centre of the Faculty of Technology and Metallurgy Karnegijeva 411120 BelgradeSerbia

This paper describes severe plastic deformation(SPD)procedures,which are utilized to form an ultrafine-grained structure in metallic *** the SPD process,a solid material sample is subjected to very high loads without a significant change in sample *** the present work,the high-pressure torsion(HPT)process,as one of the SPD techniques,which achieves a high degree of deformation and ensures refinement of the microstructure,will be discussed in more *** that grain size control is accepted as a method to obtain materials with desired characteristics,an overview of the properties of ultrafine-grained titanium-based biomaterials to be used in medicine is ***,particular attention is dedicated to the influences of HPT process parameters,primarily hydrostatic pressure,and number of revolutions during torsion,on the grain size and physical and mechanical characteristics(modulus of elasticity,microhardness,and tensile properties),corrosion resistance,and biocompatibility of the titanium-based biomaterials.A review of the literature indicates that titanium-based materials obtained by the SPD process show improved mechanical and physical properties without losing biocompatibility and corrosion resistance,which suggests that these methods of obtaining implants are something that should be further developed in the future.

关键词： high-pressure torsion process ultrafine-grained titanium-based materials electrochemical anodization physical properties mechanical properties