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Ultrafast interfacing of electrical and optical signals at the nanoscale is highly desired for on-chip applications including optical interconnects and data processing devices. Here, we report electrically driven nanoscale optical sources based on metal–insulator–graphene tunnel junctions (MIG-TJs), featuring waveguided output with broadband spectral characteristics. Electrically driven inelastic tunneling in a MIG-TJ, realized by integrating a silver nanowire with graphene, provides broadband excitation of plasmonic modes in the junction with propagation lengths of several micrometers (∼10 times larger than that for metal–insulator–metal junctions), which therefore propagate toward the junction edge with low loss and couple to the nanowire waveguide with an efficiency of ∼70% (∼1000 times higher than that for metal–insulator–metal junctions). Alternatively, lateral coupling of the MIG-TJ to a semiconductor nanowire provides a platform for efficient outcoupling of electrically driven plasmonic signals to low-loss photonic waveguides, showing potential for applications at various integration levels.

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Systemic and ophthalmological diseases are on the rise the world over, which is, to a large extent, caused by life expectancy growth. Therefore, early diagnosis, screening and monitoringpossibilities of human health parameters is becoming more and more important. Contact lenses, due to being fitted on the eye’s surface, are constantly wetted by tear fluid, and due to present-day microelectronics achievements may be used as a convenient technical means for locating a variety of sensors. The existing prototypes of electronic contact lenses (ECL) are able to monitor intraocular pressure (IOP), levels of glucose, hormones and other biomarkers that reflect the presence of ophthalmic and systemic diseases. The review discusses the publications focused on prototyping results and first laboratory tests. As of today, only one developed device is available for clinical practice (IOP monitoring), others are at different stages of research but have all potentials for being used widely.

Introduction. Selenopyran is an organic selenium compound with sharply hydrophobic properties. An increase in solubility in water (and as a consequence – and bioavailability) is possible due to the formation of inclusion complexes with cyclodextrins.Aim. The aim of this work was to study the effect of a gel containing a clathrate complex of selenopyran with β-cyclodextrin on the rate of wound healing on a model of a conditionally aseptic full-thickness planar wound in rats.Materials and methods. The object of the study was a gel containing a clathrate complex of selenopyran with β-cyclodextrin (the content of selenopyran in the gel was 0.1 %). A model of a full-thickness planar wound in sexually mature male rats was used. 20 individuals were divided into 2 groups – intact (without treatment) and experimental (received gel treatment). Efficacy was assessed by the change in wound area at 3, 5, 7, 9, 11 and 14 days after application of wound.Results and discussion. The results of the study showed that the relative area of the wounds in the treated animals by the 3rd day of the experiment was less than in the intact ones. On the fifth day of the experiment, the differences were statistically significant (57.49 ± 12.51 % in treated animals versus 85.27 ± 26.61 % in intact animals). By the 14th day of the experiment, there were practically no differences in the groups of animals.Conclusion. The results obtained indicate that when using a gel containing selenopyran in combination with β-cyclodextrin, it accelerates the transition from the inflammation phase to the proliferation phase. This is most likely due to the antioxidant properties of selenopyran. Considering the lower concentration of selenopyran in comparison with the therapeutic concentrations of other antioxidants (taurine, allantoin), it can be considered as a promising wound healing agent for further study.

Vector optical vortices exhibit complex polarization patterns due to the interplay between spin and orbital angular momenta. Here we demonstrate, both analytically and with simulations, that certain polarization features of optical vortex beams maintain constant transverse spatial dimensions independently of beam divergence due to diffraction. These polarization features appear in the vicinity of the phase singularity and are associated with the presence of longitudinal electric fields. The predicted effect may prove important in metrology and high-resolution imaging applications.

Structured light fields embody strong spatial variations of polarization, phase, and amplitude. Understanding, characterization, and exploitation of such fields can be achieved through their topological properties. Three-dimensional (3D) topological solitons, such as hopfions, are 3D localized continuous field configurations with nontrivial particle-like structures that exhibit a host of important topologically protected properties. Here, we propose and demonstrate photonic counterparts of hopfions with exact characteristics of Hopf fibration, Hopf index, and Hopf mapping from real-space vector beams to homotopic hyperspheres representing polarization states. We experimentally generate photonic hopfions with on-demand high-order Hopf indices and independently controlled topological textures, including Néel-, Bloch-, and antiskyrmionic types. We also demonstrate a robust free-space transport of photonic hopfions, thus showing the potential of hopfions for developing optical topological informatics and communications.

Valley-dependent excitation and emission in transition metal dichalcogenides (TMDCs) have recently emerged as a new avenue for optical data manipulation, quantum optical technologies, and chiral photonics. The valley-polarized electronic states can be optically addressed through photonic spin-orbit interaction of excitonic emission, typically with plasmonic nanostructures, but their performance is limited by the low quantum yield of neutral excitons in TMDC multilayers and the large Ohmic loss of plasmonic systems. Here, we demonstrate a valleytronic system based on the trion emission in high-quantum-yield WS2 monolayers chirally coupled to a low-loss microfiber. The integrated system uses the spin properties of the waveguided modes to achieve long-range directional routing of valley excitations and also provides an approach to selectively address valley-dependent emission from different spatial locations around the microfiber. This valleytronic interface can be integrated with fiber communication devices, allowing for merging valley polarization and chiral photonics as an alternative mechanism for optical information transport and manipulation in classical and quantum regimes.

The release rate of Selenopyran, a selenoxanthene synthetic derivative, from 1% gel-cream was studied using a vertical diffusion cell. The experimental results showed that, on average, 77.5% of Selenopyran of the total amount is released from a soft-dosage form sample within 3 hours.

Transverse spin momentum related to the spin angular momentum (SAM) of light has been theoretically studied recently and predicted to generate an intriguing optical lateral force (OLF). Despite extensive studies, there is no direct experimental evidence of a stable OLF resulting from the dominant SAM rather than the ubiquitous spin-orbit interaction in a single light beam. Here, we theoretically unveil the nontrivial physics of SAM-correlated OLF, showing that the SAM is a dominant factor for the OLF on a nonabsorbing particle, while an additional force from the canonical (orbital) momentum is exhibited on an absorbing particle due to the spin-orbit interaction. Experimental results demonstrate the bidirectional movement of 5-μm-diameter particles on both sides of the beam with opposite spin momenta. The amplitude and sign of this force strongly depend on the polarization. Our optofluidic platform advances the exploitation of exotic forces in systems with a dominant SAM, facilitating the exploration of fascinating light-matter interactions. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) National Research Foundation (NRF) Public Utilities Board (PUB) Published version Y.S. was supported by the Fundamental Research Funds for the Central Universities. Y.S. and A.Q.L. acknowledge the Singapore Ministry of Education (MOE) Tier 3 grant (MOE2017-T3-1-001), Singapore National Research Foundation grant (MOH-000926), A*STAR research grant (SERC A18A5b0056), and Singapore’s National Water Agency grant (PUB-1804-0082). F.N. is supported, in part, by Nippon Telegraph and Telephone Corporation (NTT) Research, the Japan Society for the Promotion of Science (JSPS) [via the Grants-in-Aid for Scientific Research (KAKENHI), grant no. JP20H00134], the Army Research Office (ARO) (grant no. W911NF-18-1-0358), the Asian Office of Aerospace Research and Development (AOARD) (via grant no. FA2386-20-1-4069), and the Foundational Questions Institute Fund (FQXi) via grant no. FQXi-IAF19-06. D.P.T. acknowledges the support from the UGC/RGC of the HKSAR, China (project no. AoE/P-502/20 and GRF project 15303521); the Department of Science and Technology of Guangdong Province (no. 2020B1515120073); the Shenzhen Science and Technology Innovation Commission (grant no. SGDX2019081623281169); and the City University of Hong Kong (grant no. 9380131). T.Z. acknowledges the Natural Science Foundation of China (NSFC), grant no. 12104083. A.V.Z. acknowledges the support from the ERC iCOMM project (789340). P.C.W. acknowledges the support from the Ministry of Science and Technology (MOST), Taiwan (grant nos. 107-2923-M-006-004-MY3, 108-2112-M-006-021-MY3, and 110-2124-M-006-004), and, in part, from the Higher Education Sprout Project of the Ministry of Education (MOE) to the Headquarters of University Advancement at National Cheng Kung University (NCKU). P.C.W. also acknowledges the support from the Ministry of Education (Yushan Young Scholar Program), Taiwan.

In this work, compacts from mechanical mixtures of CaF2 micron powder (MCP) with CaF2 nanopowder (NP) additives were produced, with mass ratios of the mixture components ranging from 10:0.125 to 10:1, respectively, using magnetic pulse (MP) and static pressing (SP) methods. The effects of pressure (Pp) and pressing temperature (Tp), concentration and phase composition of the additive on the density and color of compacts were studied, taking into account the properties of the initial components of the mixtures. The evolution of pulsed cathodoluminescence (PCL) spectra and photoluminescence (PL) of compacts from pure powders and their mixtures depending on Pp, Tp and characteristics of initial CaF2 NP was also studied. A new near-infrared (NIR) band associated with fluoride vacancies was discovered with a maximum at ~765 nm in PCL spectra of compacts produced by MP at a temperature of 425 °C. A blue band at 435 nm associated with impurity oxygen vacancies in the CaF2 lattice was found in PL spectra compacts of pure NP and powder mixtures. The density of compacts of pure NP and MCP reached 89% of the theoretical density, and the density of compacts of mixtures did not exceed 78%. The defective structure and phase composition of the CaF2 NP had a decisive effect on the luminescent properties of compacts from mixtures of micro- and nanopowders.

The effect of 100-hour aging at 1350°C on the matrix–fiber interfacial bond, matrix structure, bond type, and high-temperature strength of Nb composite reinforced with α-Al2O3 single crystal fibers has been studied. It has been found that, in the samples after pressing, as well as after 100-hour aging, no chemical interaction is detected at the matrix–fiber interface, i.e., there is no “chemical” bond, and a “mechanical” bond is realized in Bauman’s notation. At the same time, the process of mutual diffusion of matrix and fiber elements after 100-hour aging has been studied and an increase in the strength of the composite has been found. This indicates an increase in the frictional bond and/or formation of another type of bond, which at this stage does not cause fiber degradation. It was not possible to determine numerical values of the contribution of the “new type” of bonds to the increase in the strength of the composition.

Far-field analysis of small objects is severely constrained by the diffraction limit. Existing tools achieving subdiffraction resolution often utilize point-by-point image reconstruction via scanni...

AIM OF STUDY To analyze the results of lateral extra-articular tenodesis (LET) of the semitendinosus muscle tendon (STMT) and iliotibial tract (ITT) in patients with severe anterior rotational instability of the knee joint during anatomical anterograde reconstruction of the anterior cruciate ligament (rACL) with a BTB graft. MATERIAL AND METHODS We studied 138 patients with the Pivot shift test – 3+ and the Lachman test 2+ or 3+ degree after arthroscopic rACL with a BTB autograft. In 65 cases (47.1%) rACL was supplemented with LET of STMT (group 1), the remaining 73 patients (52.9%) – LET of ITT (group 2). RESULTS According to IKDC-2000, KOSS and Lysholm-Tegner scores, the groups did not differ statistically. However, pain in the LET zone, LET failure with the appearance of the Pivot shift test – 1+, revision reconstructions – were more often observed in group 2 (p

На предприятиях пищевой индустрии в больших количествах образуются отработанные растительные масла, которые остаются после приготовления различных пищевых продуктов. Эти отходы масел плохо утилизируются и загрязняют окружающую среду. В тоже время в промышленности и быту не уменьшается интерес к натуральной древесине, как природному возобновляемому материалу.Однако присущие природной древесине недостатки требуют её модификации различными составами. В работе исследованы свойства древесины берёзы, пропитанной составами на основе отработанного растительного масла. Для пропитки древесины применяли использованное после приготовления пищи рафинированное подсолнечное масло. В качестве наполнителя применяли древесную муку хвойных пород древесины и сиккатив на основе солей металлов. Пропиточный состав с сиккативом и наполнителем нагревали до заданной температуры, в который помещали образцы и выдерживали в течение определенного времени, затем переносили в пропиточный состав, имеющий температуру окружающей среды, где пропитка проходила в течение такого же времени. Пропитку осуществляли способом «горяче-холодных ванн». Свойства древесины контролировали по изменению таких показателей как водопоглощение, разбухание в радиальном и тангенциальном направлениях, а также краевого угла смачивания поверхности древесины. Пропиточные составы на основе отработанного растительного масла не имеет запаха и обладает экологической безопасностью для человека и животных. Отмечено, что использование растительного масла как чистого, так и отработанного, существенно улучшает показатели водостойкости натуральной древесины. Водопоглощение обработанной древесины после 1 суток нахождения в воде снижается в три раза, а после 30 суток испытаний – более чем в два раза по сравнению с необработанной древесиной. Показано, что наиболее оптимальным пропиточным составом на основе отработанного растительного масла для древесины березы является состав, содержащий 1 % древесной муки и 3 % сиккатива. Таким образом, обработка древесины березы составами на основе отработанного растительного масла, позволяет не только утилизировать отходы производства, но и улучшить свойства древесины, такие как водопоглощение, разбухание в тангенциальном и радиальном направлениях.

Efficient point-of-care diagnosis of severe acute respiratory syndrome-corovavirus-2 (SARS-CoV-2) is crucial for the early control of novel coronavirus infections. At present, polymerase chain reaction (PCR) is primarily used to detect SARS-CoV-2. Despite the high sensitivity, the PCR process is time-consuming and complex which limits its applicability for rapid testing of large-scale outbreaks. Here, we propose a rapid and easy-to-implement approach for SARS-CoV-2 detection based on surface enhanced infrared absorption (SEIRA) spectroscopy. The evaporated gold nano-island films are used as SEIRA substrates which are functionalized with the single-stranded DNA probes for specific binding to selected SARS-CoV-2 genomic sequences. The infrared absorption spectra are analyzed using the principal component analysis method to identify the key characteristic differences between infected and control samples. The SEIRA-based biosensor demonstrates rapid detection of SARS-CoV-2, completing the detection of 1 μM viral nucleic acids within less than 5 min without any amplification. When combined with the recombinase polymerase amplification treatment, the detection capability of 2.98 copies per μL (5 aM) can be completed within 30 min. This approach provides a simple and economical alternative for COVID-19 diagnosis, which can be potentially useful in monitoring and controlling future pandemics in a timely manner.

Hot carriers generated by plasmonic excitations have recently opened up new avenues in photocatalysis. The transfer of these energetic carriers to adjacent molecules can promote chemical transformations that are important for hydrogen generation by water splitting, CO2 reduction and degradation of organic pollutants. Here, we have developed and optimised a plasmonic hot-carrier catalytic system based on silica nanoparticles decorated with plasmonic gold nanoparticles as a source of hot carriers, equipped with platinum nanoclusters as co-catalyst for the enhancement of hot-carrier extraction. The latter plays a triple role by providing: a surface favourable for molecular adsorption; hot-electron generation near the nanoclusters due to field enhancement effects and electron momentum relaxation facilitating the electron transfer across the metal surface, exactly where molecules are adsorbed. The combination of plasmonic and catalytic metals in nano-heterostructured devices provides a new platform for photocatalytic processes and is of significant interest for future solar-based clean technologies.

It is well known that spin angular momentum of light, and therefore that of photons, is directly related to their circular polarization. Naturally, for totally unpolarized light, polarization is undefined and the spin vanishes. However, for nonparaxial light, the recently discovered transverse spin component, orthogonal to the main propagation direction, is largely independent of the polarization state of the wave. Here we demonstrate, both theoretically and experimentally, that this transverse spin survives even in nonparaxial fields (e.g., tightly focused or evanescent) generated from a totally unpolarized light source. This counterintuitive phenomenon is closely related to the fundamental difference between the degrees of polarization for 2D paraxial and 3D nonparaxial fields. Our results open an avenue for studies of spin-related phenomena and optical manipulation using unpolarized light., 11 pages, 3 figures

MATERIALS AND METHODS. We observed 164 patients from 2013 to 2019 (mean age 39.8 ± 5.1 years) who underwent anatomical antegrade ACLR ВТВ autograft . Group 1 (43 people, 31.1%) and Group 2 (48 patients, 29.3%) included patients with isolated medial GA of 2-3 degree and/or varus deformity of at least 5º. Group 3 (73 people or 44.5%) included patients with normal articular cartilage and the correct axis of the limb. In Group 1, ACLR was supplemented with an “open wedge” HVTO. The assessment was carried out according to Lysholm Knee Scoring Scale, 2000 IKDC, KOOS.RESULTS. The simultaneous performance of HVTO and ACLR shows good clinical and radiological results in 93% in the first year, and three years after surgery keeps it in 88.4%. The results of treatment of patients of Group 1 turned out to be significantly better in comparison with Group 2 (pCONCLUSION. The combined ACLR and HVTO allow reliable technology in the treatment of anterior instability in patients with GA (p< 0.05%). This approach is effective in young active middle-aged patients, with anterior instability of the knee joint and varus GA or prerequisites for its development, as well as with revision ACLR, posterior tibial plateau tilt of more than 12º. Performing HVTO simultaneously with ACLR is not practical for patients with valgus deviation of the lower leg, failure of the posterolateral capsular ligamentous complex, or changes in the external joint.

Plasmonics offers a unique opportunity to break the diffraction limit of light and bring photonic devices to the nanoscale. As the most prominent example, an integrated nanolaser is a key to truly nanoscale photonic circuits required for optical communication, sensing applications and high-density data storage. Here, we develop a concept of an electrically driven subwavelength surface-plasmon-polariton nanolaser, which is based on a novel amplification scheme, with all linear dimensions smaller than the operational free-space wavelength λ and a mode volume of under λ 3/30. The proposed pumping approach is based on a double-heterostructure tunneling Schottky barrier diode and gives the possibility to reduce the physical size of the device and ensure in-plane emission so that the nanolaser output can be naturally coupled to a plasmonic or nanophotonic waveguide circuitry. With the high energy efficiency (8% at 300 K and 37% at 150 K), the output power of up to 100 μW and the ability to operate at room temperature, the proposed surface plasmon polariton nanolaser opens up new avenues in diverse application areas, ranging from ultrawideband optical communication on a chip to low-power nonlinear photonics, coherent nanospectroscopy, and single-molecule biosensing.