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Quantum-dot microlasers based on whispering gallery mode resonators

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Light(Science & Applications) 2021年第5期10卷 785-795页

作者： A.E.Zhukov.n.v.Kryzhanovskaya E.l.Moiseev M.v.Maximov Laboratory of quantum optoelectronics National Research University Higher School of EconomicsKantemirovskaya 3ASt.Petersburg 194100Russia nanophotonics laboratory Alferov UniversityKhlopina 8/3St.Petersburg 194021Russia

The subject of this paper is microlasers with the emission spectra determined by the whispering gallery *** to the total internal reflection of light on the sidewalls,a high Q-factor is achieved until the diameter is comparable to the *** light emission predominantly occurs in the plane of the structure,which facilitates the microlaser integration with other *** focus on microdisk lasers with various types of the In(Ga)As quantum dots(QDs).Deep localization of charge carriers in spatilly separated regions suppresses the lateral diffusion and makes it possible to overcome the undesirable effect of non-adiative recombination in deep ***,using conv.n.ional epitaxial structures and relatively simple post-growth processing methods,it is possible to realize small microlasers capable of operating without temperature stabilization at elevated *** low sensitivity of QDs to epitaxial and manufacturing defects allows fabricating microlasers using IIv heterostructures grown on silicon.

关键词： Quantum mode overcome

A new Method of Synthesis of Azo Schiff Base Ligands with Azo and Azomethine Donors： Synthesis of n-4-Methoxybenzylidene-2-（3-hydroxyphenylazo）-5-hydroxyaniline and Its nickel（Ⅱ） Complex

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Chinese Journal of Chemistry 2007年第6期25卷 869-871页

作者： OFORKA, n. C. MKPEnIE, v. n. Department of Pure and Industrial Chemistry University of Port Harcourt P. M. B. 5323 Port Harcourt Nigeria

A new method for the synthesis of azo Schiff an base ligand in which the azo and azomethine groups are coordination sites was developed through a Schiff base precursor. The precursor, n-4-methoxybenzylidene-3-hydroxyphenylamine （SB） derived from 3-aminophenol was regioselectively coupled with a diazonium ion para to the hydroxyl group of the amine component of the Schiff base. The para selectivity was controlled by the directing effect of the hydroxyl group. The ligand and its nickel（Ⅱ） complex were characterized by elemental analyses, IR and Uv-vis spectroscopy. The analytical and spectral data supported the mononuclear formulation of the complex with metal to ligand ratio （M ： L = 1 ： 2） and suggested a square planar geometry for the complex.

关键词： synthesis azo compound Schiff base ligand azo and azomethine donor

Melt-spun thin ribbons of shape memory TiniCu alloy for micromechanical applications

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International Journal of Smart and nano Materials 2011年第2期2卷 68-77页

作者： A.v.Shelyakov.n.n.Sitnikov v.v.Koledov D.S.Kuchin A.I.Irzhak n.Yu.Tabachkova Department of Solid State Physics and nanosystems National Research Nuclear University“MEPhI”Kashirskoe shosse 31115409 MoscowRussian Federation Department of Physics of Magnetic Phenomena Kotelnikov Institute of Radio-Engineering and Electronics of Russian Academy of SciencesMohovaya st.11/7125009 MoscowRussian Federation Department of Material Science of Semiconductors and Dielectrics National University of Science and Technology“MISiS”Leninsky prospect 4119049 MoscowRussian Federation

The development of micromechanical devices(MEMS and nEMS)on the basis of nanostructured shape memory alloys is reported.A Ti_(50)ni_(25)Cu_(25)(at.%)alloy fabricated by the melt spinning technique in the form of a ribbon with a thickness around 40µm and a width about 1.5 mm was chosen as a starting *** parameters were optimized to produce the alloy in an amorphous *** thickness of the ribbon was reduced to 5–14µm by means of electrochemical polishing.A nanostructural state of the thin ribbons was obtained via the dynamic crystallization of the amorphous alloy by application of a single electric pulse with duration in the range of 300–900µs.A microtweezers prototype with a composite cantilever of 0.8µm thick and 8µm long was developed and produced on the basis of the obtained nanostructured thin ribbons by means of the focused ion beam *** deformation of the micromanipulator was achieved by heating using semiconductor laser radiation in a vacuum chamber of scanning ion-probe microscope.

关键词： melt-spun ribbon shape memory alloy composite micromanipulator microtweezers

Malpractice or masterful practice?navigating vicarious liability in healthcare

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World Journal of Clinical Cases 2025年第2期13卷 10-13页

作者： Satvik n Pai naveen Jeyaraman Madhan Jeyaraman Swaminathan Ramasubramanian Department of Orthopaedics PES University Institute of Medical Sciences and ResearchBengaluru 560100KarnatakaIndia Department of Orthopaedics ACS Medical College and HospitalDr MGR Educational and Research InstituteChennai 600077Tamil NaduIndia Department of Orthopaedics Government Medical CollegeOmandurar Government EstateChennai 600002Tamil NaduIndia

In the intricate landscape of healthcare,vicarious liability looms large,shaping the responsibilities and actions of healthcare practitioners and administrators *** by a poignant scenario of a medication error,this article navigates the complexities of vicarious liability in *** explains the legal basis and ramifications of this theory,emphasizing its importance in fostering responsibility,protecting patient welfare,and easing access to *** paper explores the practical effects of vicarious responsibility on day-to-day operations,leadership practices,and decision-making processes via the eyes of senior consultants,junior doctors,and hospital *** comprehensive insights and real-world examples,it underscores the imperative of fostering a culture of accountability,communication,and quality care to navigate the intricate web of liabilities inherent in modern healthcare.

关键词： vicarious liability Healthcare Responsibility Litigation Patient welfare

Anode Plasma Electrolytic Saturation of Titanium Alloys with nitrogen and Oxygen

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Journal of Materials Science & Technology 2016年第10期32卷 1027-1032页

作者： P.n.Belkin S.A.Kusmanov A.v.Zhirov v.S.Belkin v.I.Parfenyuk nekrasov Kostroma State University 1 May14Kostroma 156961Russia

In this work, we investigated the features of the anode plasma electrolytic saturation of titanium alloys with nitrogen and oxygen. In this case, the titanium samples may be heated to 1050 ℃ using aqueous solutions of ammonium chloride as working electrolyte. The weight of titanium samples is found to change due to their oxidation and anode dissolution. An X-ray diffractometer, a scanning electron microscope,nuclear proton backscattering and an optical microscope were used to characterize the phase and elemental composition of the modified layer. The electrolyte composition（10 wt% ammonium chloride, 5wt% ammonia） and processing mode（850 ℃, 5 min） of commercially pure titanium（CP-Ti） allowing to obtain the hardened surface layer up to 0.1 mm with microhardness of 220 Hv were proposed. Surface roughness Ra of samples after their nitriding for 5 min at 800 ℃ decreases from 1.67 to 0.082 μm. The anode plasma electrolytic nitriding could decrease friction coefficient and increase wear resistance of the CP-Ti. It is found that the anodic nitriding of low alloy titanium alloys reduces their corrosion rate in an aqueous solution of sulphuric（4.5%） and salt（0.2%） acids by 2 orders of magnitude. Results of cyclic testing show that anodic nitriding of commercial titanium leads to a decrease in corrosion rate by 8 times in solution of hydrochloric acid（6%） with addition of protein and vitamin.

关键词： Plasma electrolysis Titanium nitriding Wear Corrosion

Glass and cellulose acetate fibers-supported boehmite nanosheets for bacteria adsorption

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Progress in natural Science:Materials International 2017年第2期27卷 268-274页

作者： n.v.Svarovskaya O.v.Bakina E.A.Glazkova A.n.Fomenko M.I.Lerner Institute of Strength Physics and Materials Sciences of the Siberian Branch of the Russian Academy of Sciences national Research Tomsk Polytechnic University

In this work, in situ method of producing hybrid fibrous adsorbents in which boehmite nanosheets with high sorption properties formed on the surface of hydrophilic microfibres, such as cellulose acetate and glass fibre,was described. The boehmite nanosheets were fabricated by the reaction of composite Al n/Al nanoparticles with water at 60 °C. The synthesized samples were characterized by X-ray diffractometer, scanning, transmission electron microscopy, Fourier transform infrared spectrometer(FT-IR), zeta-potential and specific surface area analyzers. The introduction of microfibres into a diluted aqueous suspension of nanopowders causes heteroadagulation of the nanoparticles and accelerates their further transformation. This effect is most substantial with the glass microfibre, which is thought to have a higher concentration of surface groups capable of generating hydrogen bonds that act as heteroadagulation and nucleation centres. The experimental results showed that the morphology of the resultant hybrid fibrous adsorbents differed accordingly: the nanosheets were attached on-edge to the glass microfibre surface, while on the surface of the cellulose acetate microfibre,they were secured in the form of spherical "nanoflowers" of agglomerated nanosheets. The effect of the morphology of hybrid fibrous adsorbents on adsorption bacteria Escherichia coli was also investigated.

关键词： nanosheets Microfibres Hybrid materials Bacterial adsorption

Arrestins:structural disorder creates rich functionality

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Protein & Cell 2018年第12期9卷 986-1003页

作者： vsevolod v.Gurevich Eugenia v.Gurevich vladimir n.Uversky Department of Pharmacology Vanderbilt UniversityNashvilleTN 37232USA Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute Morsani College of Medicine University of South FloridaTampaFL 33612USA Institute for Biological Instrumentation Russian Academy of SciencesPushchinoMoscow RegionRussia 142290

Arrestins are soluble relatively small 44-46 kDa proteins that specifically bind hundreds of active phosphorylated GPCRs and dozens of non-receptor partners. There are binding partners that demonstrate preference for each of the known arrestin conformations: free, receptor-bound, and microtubule-bound. Recent evidence suggests that conformational flexibility in every functional state is the defining characteristic of arrestins. Flexibility, or plasticity, of proteins is often described as structural disorder, in contrast to the fixed conformational order observed in high-resolution crystal structures. However, protein-protein interactions often involve highly flexible elements that can assume many distinct conformations upon binding to different partners. Existing evidence suggests that arrestins are no exception to this rule: their flexibility is necessary for functional versatility. The data on arrestins and many other multi-functional proteins indicate that in many cases, "order" might be artificially imposed by highly non-physiological crystallization conditions and/or crystal packing forces. In contrast, conformational flexibility (and its extreme case, intrinsic disorder) is a more natural state of proteins, representing true biological order that underlies their physiologically relev.n. functions.

关键词： EPR GPCR nMR arrestin crystal structure disorder protein-protein interactions

Stability of Macroscopic Binary Systems

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Communications in Theoretical Physics 2019年第11期71卷 1335-1340页

作者： G.G.Adamian n.v.Antonenko H.Lenske v.v.Sargsyan Joint Institu te for nuclear Research 141980 DubnaRussia Ins titut fur Theore tische Physik der Jus tus-Liebig—Uni versit nt D-35392 GiessenGermany

The Darwin instability effect in the binary systems(di-planets, di-stars, and di-galaxies) is analyzed within the model based on the Regge-like laws. All possible binary stars are found satisfying the Darwin instability condition that requires to search for other mechanism triggering the merger of the contact binary objects. new analytical formulas are obtained for the orbital rotation period and the relative distance between components of the binary system. The decreasing and increasing periods as functions of mass asymmetry are related, respectively, with the non-overlapping and overlapping stage of the binary object evolution.

关键词： Regge laws binary stars and galaxies Darwin instability effect

nEAR-InFRARED MOnITORInG OF THE LUMBAR ERECTOR SPInAE MUSCLE In HEALTHY MEn AnD WOMEn DURInG STATIC AnD DYnAMIC EnDURAnCE WORK

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Journal of Innovative Optical Health Sciences 2011年第2期4卷 173-182页

作者： RAMMOHAn v.MAIKALA YAGESH n.BHAMBHAnIy Liberty Mutual Research Institute for Safety 71 Frankland Road HopkintonMA 01748USA Faculty of Rehabilitation Medicine University of Alberta Edmonton Alberta T6G 2G4Canada

Understanding muscle hemodynamics using near-infrared spectroscopy is increasingly evident in the recent spinal disorders-related ***,none of these human studies addressed the issue of physiological limits for the lumbar muscle within the same participants during various exercise *** purpose of this study is to evaluate physiological limits for the lumbar muscle during dynamic and static endurance *** three separate days,22 healthy men and women performed three endurance protocols(static prone trunk extension,arm cranking,and pushingpulling)until volitional *** each protocol,minimum and maximum oxygenation and blood volume responses from the right lumbar erector spinae were obtained using a continuous dual wavelength near-infrared spectroscopy(Micro-Runman,nIM Inc.,PA,USA).Statistical analysis showed that greatest reduction in oxygenation(minimum)were obtained during dynamic exercises:pushingpulling(2.1 times)and arm cranking(2.03 times)versus static test (Pnge(calculated as the difference between maximum during recovery and minimum at the point of volitional exhaustion)during static test was lower[(66-75%for oxygenation)and(34-46%for blood volume)]than dynamic exercises (Pntrary to the theory that sufficient occlusion of bloodflow to the lumbar muscle is possible with static trunk extension,it was concluded that a dynamic protocol until volitional exhaustion might be a good alternative in establishing near-infrared spectroscopy-derived physiological limits to the lumbar *** research is essential to identify an optimal calibration procedure for establishing true hypoxic values for the human lumbar muscle.

关键词： Arm cranking back muscle endurance gender differences oxygenation and blood volume pushingpulling Sorensen test