Direct amplitude-phase near-field observation of higher-order anapole states

Anapole states associated with the resonant suppression of electric-dipole scattering exhibit minimized extinction and maximized storage of electromagnetic energy inside a particle. Using numerical simulations, optical extinction spectroscopy and amplitude-phase near-field mapping of silicon dielectric disks, we demonstrate high-order anapole states in the near-infrared wavelength range (900-1700 nm). We develop the procedure for unambiguously identifying anapole states by monitoring the normal component of the electric near-field and experimentally detect the first two anapole states as verified by far-field extinction spectroscopy and confirmed with the numerical simulations. We demonstrate that higher order anapole states possess stronger energy concentration and narrower resonances, a remarkable feature that is advantageous for their applications in metasurfaces and nanophotonics components, such as non-linear higher-harmonic generators and nanoscale lasers

Sintering oxide ceramics based on AI[2]O[3] and ZrO[2], activated by MgO, TiO[2] and SiO[2] additives

The positive effect of the addition of MgO and TiO[2] in an amount of no more than 1 wt. % on sintering and physico-mechanical properties of alumina ceramics is established. Addition of 5% of SiO[2] to A1[2]O[3] provides the mechanism of liquid phase sintering of ceramics, which leads to increase in its density and strength up to 480 MPa. In ceramic system A1[2]O[3] - ZrO[2] - Y[2]O[3] highest level of physical and mechanical properties of the composition had a hypereutectic composition 16.6% A1[2]O[3] - 76% Z1O[2] - 7.4% Y[2]O[3]. In this composition two mechanisms of hardening are realized simultaneously, such as transformational hardening by t-m -ZrO[2] transition and dispersion strengthening with high-modulus particles of [alpha]- A1[2]O[3]

Stromal and Tumor Glioma-Derived Cells with Similar Characteristics have Differences in α-Smooth Muscle Actin Expression and Localization

Gliomas are solid brain tumors composed of tumor cells and recruited heterogenic stromal components. The study of the interactions between the perivascular niche and its surrounding cells is of great value in unraveling mechanisms of drug resistance in malignant gliomas. In this study, we isolated the stromal diploid cell population from oligodendroglioma and a mixed population of tumor aneuploid and stromal diploid cells from astrocytoma specimens. The stromal cells expressed neural stem/progenitor and mesenchymal markers showing the same discordant phenotype that is typical for glioma cells. Moreover, some of the stromal cells expressed CD133. For the first time, we demonstrated that this type of stromal cells had the typical myofibroblastic phenotype as the α-SMA+ cells formed α-SMA fibers and exhibited the specific function to deposit extracellular matrix (ECM) proteins at least in vitro. Immunofluorescent analysis showed diffuse or focal α-SMA staining in the cytoplasm of the astrocytoma-derived, A172, T98G, and U251MG glioma cells. We could suggest that α-SMA may be one of the main molecules, bearing protective functions. Possible mechanisms and consequences of α-SMA disruptions in gliomas are discussed

The Standard Model Prediction of the Muon Anomalous Magnetic Moment

This article reviews and updates the Standard Model prediction of the muon g-2. QED, electroweak and hadronic contributions are presented, and open questions discussed. The theoretical prediction deviates from the present experimental value by 2-3 standard deviations, if e+e- annihilation data are used to evaluate the leading hadronic term.Comment: 30 pages, 8 figures. v2: Updated version to appear in J.Phys.G. Comments and references added, typo corrected in eq.(17

Boosting Local Field Enhancement by on-Chip Nanofocusing and Impedance-Matched Plasmonic Antennas

Strongly confined surface plasmon-polariton modes can be used for efficiently delivering the electromagnetic energy to nano-sized volumes by reducing the cross sections of propagating modes far beyond the diffraction limit, i.e., by nanofocusing. This process results in significant local-field enhancement that can advantageously be exploited in modern optical nanotechnologies, including signal processing, biochemical sensing, imaging and spectroscopy. Here, we propose, analyze, and experimentally demonstrate on-chip nanofocusing followed by impedance-matched nanowire antenna excitation in the end-fire geometry at telecom wavelengths. Numerical and experimental evidences of the efficient excitation of dipole and quadrupole (dark) antenna modes are provided, revealing underlying physical mechanisms and analogies with the operation of plane-wave Fabry-P\'erot interferometers. The unique combination of efficient nanofocusing and nanoantenna resonant excitation realized in our experiments offers a major boost to the field intensity enhancement up to $\sim 12000$, with the enhanced field being evenly distributed over the gap volume of $30\times 30\times 10\ {\rm nm}^3$, and promises thereby a variety of useful on-chip functionalities within sensing, nonlinear spectroscopy and signal processing

Engineering nanoparticles with pure high-order multipole scattering

The ability to control scattering directionality of nanoparticles is in high demand for many nanophotonic applications. One of the challenges is to design nanoparticles producing pure high-order multipole scattering (e.g., octopole, hexadecapole), whose contribution is usually negligible compared to strong low-order multipole scattering (i.e., dipole or quadrupole). Here we present an intuitive way to design such nanoparticles by introducing a void inside them. We show that both shell and ring nanostructures allow regimes with nearly pure high-order multipole scattering. Experimentally measured scattering diagrams from properly designed silicon rings at near-infrared wavelengths (~ 800 nm) reproduce well scattering patterns of an electric octopole and magnetic hexadecapole. Our findings advance significantly inverse engineering of nanoparticles from given complex scattering characteristics, with possible applications in biosensing, optical metasurfaces, and quantum communications.Comment: Submitted to ACS Photonic

ОПЫТ ПРИМЕНЕНИЯ РИВАРОКСАБАНА У ПАЦИЕНТОВ С ТРЕПЕТАНИЕМ ПРЕДСЕРДИЙ 1-ГО ТИПА: ЭФФЕКТИВНОСТЬ, БЕЗОПАСНОСТЬ, КОМПЛАЕНТНОСТЬ

Aim. To assess effectiveness, safety and adherence to treatment of patients with type I atrial flutter who were previously excluded from the clinical trials evaluating the potential benefits of rivoroxaban for thromboembolism prevention.Methods. 27 medical records of patients with type I atrial flutter were retrospectively reviewed and assigned to the study group. The control group consisted of 100 patients with atrial fibrillation. Both groups received rivoroxaban. All patients underwent thromboembolism risk assessment with the CHA2DS2-VACs score, bleeding risk assessment with HAS-BLED score. Data were collected by telephone.Results. No thromboembolic events were registered in the atrial flutter group, whereas one case of ischemic stroke was in the atrial fibrillation group. There were no major bleedings in both groups. Four patients with atrial flutter and 2 patients with atrial fibrillation had hemorrhages. Patients’ adherence to rivoroxaban was 75–80%.Conclusion. Rivoroxaban therapy was found to be effective and safe in patients with type I atrial flutter including those who underwent cardioversion. High adherence to rivoroxaban therapy was demonstrated.Цель. Оценить с позиции безопасности, эффективности и комплаентности к лечению группу пациентов с трепетанием предсердий 1-го типа, ранее не включенных в рандомизированные исследования по вопросам профилактики тромбоэмболических осложнений на фоне приема ривароксабана.Материалы и методы. Исследование имело ретроспективный характер, в исследование включено 27 пациентов с трепетанием предсердий 1-го типа, группой сравнения стали 100 пациентов с фибрилляцией предсердий. Обе группы в качестве антитромботической поддержки получали ривароксабан, пациентам проводили оценку риска тромбоэмболии о шкале CHA2DS2-VASc, оценку риска кровотечений по шкале HAS-BLED использовался метод сбора информации путем телефонного анкетирования.Результаты. В группе трепетания предсердий не зафиксировано тромбоэболических осложнений, в группе фибрилляции предсердий выявлен один случай ишемического инсульта, значимых кровотечений не было ни в одной из групп. Геморрагический синдром зафиксирован у четырех пациентов с трепетанием предсердий и у двух – в группе фибрилляции предсердий. Комплаентность к терапии ривароксабаном составила 75–80% в обеих группах.Заключение. Подтверждена эффективность и безопасность ривароксабана у пациентов с трепетанием предсердий 1-го типа, в том числе для антитромботической поддержки кардиоверсии, а также высокий комплайнс к подобному лечению