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Journal of Rare Earths 2019年第11期37卷 1152-1156页

作者： Marcin Runowski inocencio R.Martin Vladimir N.Sigaev vitaliy i.savinkov Georgiy Yu.Shakhgildyan Stefan Lis Faculty of Chemistry Adam Mickiewicz UniversityUniwersytetu Poznanskiego 861-614 PoznanPoland Departamento de Fisica Instituto de Materiales y Nanotecnologia(IMN)Universidad de La LagunaApdo.456E-38200 San Cristobal de La LagunaSanta Cruz de TenerifeSpain D.Mendeleev University of Chemical Technology Miusskaya Sq.9125047 MoscowRussia

Multifunctional core/shell type,luminescent-plasmonic material composed of lanthanide doped microspheres(≈50μm)and gold nanoparticles(Au NPs;≈10-20 nm)deposited onto their surface,were successfully prepared(Nd^3+:YAS@Au).The material was synthesized to combine the luminescence properties of the Nd^3+-doped microspheres,*** resonance with plasmonic activity of the surface Au NPs,*** enhanced Raman scattering(SERS)effect,within a single,micro-sized *** luminescent-plasmonic microspheres were used as the active SERS substrate for detection of the organic probe,and for generation of Whispering Gallery Modes(WGM),which red-shift together with increasing laser power(temperature elevation).The products obtained were analysed with optical,scanning and transmission electron microscopy(SEM and TEM),as well as by Raman,absorption and photoluminescence spectroscopies.

关键词： Luminescence Gold NPs-SPR Surface enhanced Raman scattering Microsphere resonators-WGM Lanthanide ions Optical sensors

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

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

Structural Changes and Electrodynamic Effects in Polymers under Fast Uniaxial Compression

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Chinese Journal of Polymer Science 2021年第5期39卷 601-609,I0007页

作者： Aleksey.i.Aleksandrov ivan A.Aleksandrov vitaliy G.Shevchenko Aleksandr N.Ozerin N.S.Enikolopov institute of Synthetic Polymeric Materials RAS 117393 Moscow Profsoyuznaya70 Russian Federation

Rheological explosion in polymers under uniaxial compression in an open volume occurs at the end of continuous rapid plastic deformation after several stages of *** types of polymers were chosen for this study:brittle glassy amorphous polystyrene and thermoplastic semi-crystalline *** pulses were detected during explosion,and their spectra were analyzed with two models.X-ray diffraction methods were used to investigate changes in the structure and morphology of polymers during deformation and rheological *** pores appear in polymer in this process,and their shape and size distribution were derived from X-ray *** main reason for the formation of pores in polymer samples in rheological explosion experiments is the intense microshifts in the polymer volume under the action of high applied pressure.

关键词： Polystyrene Polypropylene X-ray Mechanical properties Compression

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

Acute acalculous cholecystitis in children

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World Journal of Gastroenterology 2018年第43期24卷 4870-4879页

作者： Dimitri Poddighe vitaliy Sazonov Department of Medicine School of MedicineNazarbayev University Pediatric intensive Care Unit UMC National Research Center for Mother and Child Health

Acute acalculous cholecystitis(AAC) is the inflammatory disease of the gallbladder in the absence of gallstones. AAC is estimated to represent at least 50% to 70% of all cases of acute cholecystitis during childhood. Although this pathology was originally described in critically ill or post-surgical patients, most pediatric cases have been observed during several infectious diseases. in addition to cases caused by bacterial and parasitic infections, most pediatric reports after 2000 described children developing AAC during viral illnesses(such as Epstein-Barr virus and hepatitis A virus infections). Moreover, some pediatric cases have been associated with several underlying chronic diseases and, in particular, with immune-mediated disorders. Here, we review the epidemiological aspects of pediatric AAC, and we discuss etiology, pathophysiology and clinical management, according to the cases reported in the medical literature.

关键词： Acute acalculous cholecystitis Children Viral biliary disorders

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

Effectiveness of Bilateral Pulmonary Artery Banding in Patients with Hypoplastic Left Heart Syndrome and Congenital Heart Defects with a Functional Single Ventricle: A Single-Center Retrospective Study

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Congenital Heart Disease 2022年第3期17卷 365-374页

作者： vitaliy Suvorov Vladimir Zaitcev Karolina Andrzejczyk Saint Petersburg State Pediatric Medical University Saint-PetersburgRussia Academisch Medisch Centrum Universiteit van Amsterdam AmsterdamNetherlands

Background:Bilateral banding of the branches of the pulmonary artery in patients with hypoplastic left heart syndrome(HLHS)and other duct dependent critical neonatal heart malformations can significantly reduce the incidence of severe complications in the postoperative period,especially in severely unstable *** our study we compared different surgical techniques of bilateral pulmonary artery banding(PAB)in respect to their success in balancing systemic and pulmonary blood ***:We included 44 neonates with a HLHS and congenital heart diseases(CHD)with a functional single ventricle underwent a hybrid operation:bilateral PAB and patent ductus arteriosus *** hybrid surgery for method No.1 is performed as a one-stage procedure,together with patent ductus arteriosus(PDA)*** median sternotomy,two Gore-Tex 1–2 mm wide bands with a diameter of 3–3.5 mm are *** we apply method No.2 then the thread is used to create *** No.3 is distinguished by intraoperative assessment of blood flow at the site of narrowing of the branches of the pulmonary artery and optional stenting of the *** cuff for banding is made of Gore-Tex *** when applying method Nos.1 and 2 is assessed by the change in invasive blood pressure and oxygen saturation after narrowing of the branches of the pulmonary ***,with these techniques PDA stenting by inserting the introducer via pulmonary artery trunk is ***:HLHS with mitral or aortic valve atresia or both was present in 19 patients(43.1%),with severe left heart obstruction resulting in PDA dependent systemic circulation in 16 babies(36.4%).CHD with single ventricle physiology occurred in 9 patients(20.5%).14 babies(31.8%)undergo the procedure following the method No.1,8 patients(18.2%)method No.2 and 22 patients(50%)method ***/Qs=1/1 was achieved in 30 patients(30/44,68.1%):as a result of the method No.1 was achieved in 5 patients(5/14,35.7%),method No.2 in 4 patien

关键词： Bilateral banding hybrid Norwood procedure pulmonary banding hybrid approach HLHS surgery single ventricle

Optimization of Artificial Viscosity in Production Codes Based on Gaussian Regression Surrogate Models

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Communications on Applied Mathematics and Computation 2024年第3期6卷 1521-1550页

作者： vitaliy Gyrya Evan Lieberman Mark Kenamond Mikhail Shashkov Applied Mathematics and Plasma Physics Theoretical DivisionMail Stop B284Los Alamos National LaboratoryLos AlamosNM 87545USA Continuum Models and Numerical Methods Group X-Computational Physics DivisionMail Stop F644Los Alamos National LaboratoryLos AlamosNM 87545USA Lagrangian Codes Group X-Computational Physics DivisionMail Stop T086Los Alamos National LaboratoryLos AlamosNM 87545USA

To accurately model flows with shock waves using staggered-grid Lagrangian hydrodynamics, the artificial viscosity has to be introduced to convert kinetic energy into internal energy, thereby increasing the entropy across shocks. Determining the appropriate strength of the artificial viscosity is an art and strongly depends on the particular problem and experience of the researcher. The objective of this study is to pose the problem of finding the appropriate strength of the artificial viscosity as an optimization problem and solve this problem using machine learning (ML) tools, specifically using surrogate models based on Gaussian Process regression (GPR) and Bayesian analysis. We describe the optimization method and discuss various practical details of its implementation. The shock-containing problems for which we apply this method all have been implemented in the LANL code FLAG (Burton in Connectivity structures and differencing techniques for staggered-grid free-Lagrange hydrodynamics, Tech. Rep. UCRL-JC-110555, Lawrence Livermore National Laboratory, Livermore, CA, 1992, 1992, in Consistent finite-volume discretization of hydrodynamic conservation laws for unstructured grids, Tech. Rep. CRL-JC-118788, Lawrence Livermore National Laboratory, Livermore, CA, 1992, 1994, Multidimensional discretization of conservation laws for unstructured polyhedral grids, Tech. Rep. UCRL-JC-118306, Lawrence Livermore National Laboratory, Livermore, CA, 1992, 1994, in FLAG, a multi-dimensional, multiple mesh, adaptive free-Lagrange, hydrodynamics code. in: NECDC, 1992). First, we apply ML to find optimal values to isolated shock problems of different strengths. Second, we apply ML to optimize the viscosity for a one-dimensional (1D) propagating detonation problem based on Zel’dovich-von Neumann-Doring (ZND) (Fickett and Davis in Detonation: theory and experiment. Dover books on physics. Dover Publications, Mineola, 2000) detonation theory using a reactive burn model. We compare re

关键词： Optimization Artificial viscosity Gaussian regression surrigate model

Plural interactions of space charge wave harmonics during the development of two-stream instability

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Chinese Physics B 2015年第9期24卷 332-336页

作者： Victor Kulish Alexander Lysenko Michael Rombovsky vitaliy Koval iurii Volk National Aviation University Department of Theoretical Physics Sumy State University Department of General and Theoretical Physics

We construct a cubically nonlinear theory of plural interactions between harmonics of the growing space charge wave（SCW） during the development of the two-stream instability. it is shown that the SCW with a wide frequency spectrum is formed when the frequency of the first SCW harmonic is much lower than the critical frequency of the two-stream *** SCW has part of the spectrum in which higher harmonics have higher amplitudes. We analyze the dynamics of the plural harmonic interactions of the growing SCW and define the saturation harmonic levels. We find the mechanisms of forming the multiharmonic SCW for the waves with frequencies lower than the critical frequency and for the waves with frequencies that exceed the critical frequency.

关键词： two-stream instability three-wave parametric resonances space charge wave free-electron laser