Universal Microwave Photonics Approach to Frequency-Coded Quantum Key Distribution

Design principles of universal microwave photonics system (MPS) for quantum key distribution (QKD) with frequency coding are concerned. Its main modulation concept lies in single photon generation on sidebands of optical carrier and determination of photons ground state through its registration and the amplitude value of its carrier frequency as reference channel. So, it is necessary to solve problems of signal-to-carrier ratio of single photon detector (SPD) and aspects of photon number splitting (PNS) attack, nonlinear phase modulation (NPM) between carrier and sidebands in fiber, and finally, spectral selection of carrier in receiver. The technologies, based on the modulation conversion of an optical carrier, are widely used in microwave photonics. Due to the natural symmetry of modulated signals and the highest achievable ratio of the modulation conversions, amplitude-phase modulation with complete or partial suppression of the optical carrier has found a particularly wide application in MPS. The characteristics of advanced MPS for QKD with frequency coding and carrier suppression based on tandem amplitude modulation and phase commutation are presented. New systems can have classical symmetric or non-classical asymmetric structure for QKD based only on spectral selection of carrier and subcarriers without re-modulation

ϒ production in p–Pb collisions at √sNN=8.16 TeV

ϒ production in p–Pb interactions is studied at the centre-of-mass energy per nucleon–nucleon collision √sNN = 8.16 TeV with the ALICE detector at the CERN LHC. The measurement is performed reconstructing bottomonium resonances via their dimuon decay channel, in the centre-of-mass rapidity intervals 2.03 < ycms < 3.53 and −4.46 < ycms < −2.96, down to zero transverse momentum. In this work, results on the ϒ(1S) production cross section as a function of rapidity and transverse momentum are presented. The corresponding nuclear modification factor shows a suppression of the ϒ(1S) yields with respect to pp collisions, both at forward and backward rapidity. This suppression is stronger in the low transverse momentum region and shows no significant dependence on the centrality of the interactions. Furthermore, the ϒ(2S) nuclear modification factor is evaluated, suggesting a suppression similar to that of the ϒ(1S). A first measurement of the ϒ(3S) has also been performed. Finally, results are compared with previous ALICE measurements in p–Pb collisions at √sNN = 5.02 TeV and with theoretical calculations.publishedVersio

Intellectual parachute monitoring system based on twisted fiber optic sensors

For any parachute system, it is important to predict the opening forces it will experience in order to make a safe and economic choice of materials to be used. Pre-design researches on creation of the built-in parachute parameters monitoring system that can be used both at a stage of its tests, and at stage of its control for the purpose of its characteristics management are resulted. Fiber optic sensor based on two twisted fibers with the locked ends offered by us for this purpose does not demand lamination, is indifferent to a temperature field, and provides a wide dynamic range of measurement as pressure and tension of parachute elements. Developed fiber optic sensors have variable twisting step and have been used for creation of intellectual knots of perspective vehicles, in particular, parachute canopies and slings. We decided to change our measuring procedure from checking of transmitted power or its Rayleigh scattering in different ends of twisted fibers onto Brillouin scattering characterization. For this situation, we offered the kind of frequency variation method to get the information about the frequency shift and Q-factor of the Brillouin scattering in each sensor

Optical Properties of LiGdF₄ Single Crystal in the Terahertz and Infrared Ranges

The basic mechanisms of absorption of THz range radiation in optically perfect LiGdF4 single crystals were studied using the broadband experimental data and the dielectric response function analysis within the harmonic oscillator model. The polarized IR reflection spectra have allowed one to determine the phonon contribution in the absorption coefficient in the THz range, while transmission spectra in the THz range were used to obtain the birefringence value and the effects of various mulitparticle processes. Additionally, we established the optical and electrodynamic parameters of the LiGdF4 single crystal, which are necessary for the design of nonlinear optical devices

The Problems of Passive Remote Sensing of the Earth’s Surface in the Range of 1.2–1.6 GHz

The main problems of remote sensing of the Earth&rsquo;s surface within the frequency range 1.2&ndash;1.6 GHz are discussed. They are related to the resonant quantum properties of the radio wave propagation medium in the lower ionosphere. It is shown that, for the passive remote sensing, the main source is incoherent microwave radiation of the D and E ionospheric layers in the decimeter range. For the first time, a theoretically grounded principally new scheme of measurements is suggested. The scheme assumes that the radiation source exists below the satellite orbit and accounts for the fact that two types of radiation (direct and reflected) reach the satellite sensor. The separation of the respective fluxes is a serious problem that should be solved for the correct interpretation of the measurements. The question is raised regarding the correct calibration of measuring equipment, depending on the current state of the ionosphere

WAX INDUCER 1 Regulates β-Diketone Biosynthesis by Mediating Expression of the <i>Cer-cqu</i> Gene Cluster in Barley

Plant surface properties are crucial determinants of resilience to abiotic and biotic stresses. The outer layer of the plant cuticle consists of chemically diverse epicuticular waxes. The WAX INDUCER1/SHINE subfamily of APETALA2/ETHYLENE RESPONSIVE FACTORS regulates cuticle properties in plants. In this study, four barley genes homologous to the Arabidopsis thaliana AtWIN1 gene were mutated using RNA-guided Cas9 endonuclease. Mutations in one of them, the HvWIN1 gene, caused a recessive glossy sheath phenotype associated with β-diketone deficiency. A complementation test for win1 knockout (KO) and cer-x mutants showed that Cer-X and WIN1 are allelic variants of the same genomic locus. A comparison of the transcriptome from leaf sheaths of win1 KO and wild-type plants revealed a specific and strong downregulation of a large gene cluster residing at the previously known Cer-cqu locus. Our findings allowed us to postulate that the WIN1 transcription factor in barley is a master mediator of the β-diketone biosynthesis pathway acting through developmental stage- and organ-specific transactivation of the Cer-cqu gene cluster

Near panmixia at the distribution‐wide scale but evidence of genetic differentiation in a geographically isolated population of the Terek Sandpiper Xenus cinereus

Abstract Populations from different parts of a species range may vary in their genetic structure, variation and dynamics. Geographically isolated populations or those located at the periphery of the range may differ from those located in the core of the range. Such peripheral populations may harbour genetic variation important for the adaptive potential of the species. We studied the distribution‐wide population genetic structure of the Terek Sandpiper Xenus cinereus using 13 microsatellite loci and the mitochondrial DNA (mtDNA) control region. In addition, we estimated whether genetic variation changes from the core towards the edge of the breeding range. We used the results to evaluate the management needs of the sampled populations. Distribution‐wide genetic structure was negligible; the only population that showed significant genetic differentiation was the geographically isolated Dnieper River basin population in Eastern Europe. The genetic variation of microsatellites decreased towards the edge of the distribution, supporting the abundant‐centre hypotheses in which the core area of the distribution preserves the most genetic variation; however, no such trend could be seen with mtDNA. Overall genetic variation was low and there were signs of past population contractions followed by expansion; this pattern is found in most northern waders. The current effective population size (Ne) is large, and therefore global conservation measures are not necessary. However, the marginal Dnieper River population needs to be considered its own management unit. In addition, the Finnish population warrants conservation actions due to its extremely small size and degree of isolation from the main range, which makes it vulnerable to genetic depletion

Spatiotemporal Dynamics of Virus Infection Spreading in Tissues

Virus spreading in tissues is determined by virus transport, virus multiplication in host cells and the virus-induced immune response. Cytotoxic T cells remove infected cells with a rate determined by the infection level. The intensity of the immune response has a bell-shaped dependence on the concentration of virus, i.e., it increases at low and decays at high infection levels. A combination of these effects and a time delay in the immune response determine the development of virus infection in tissues like spleen or lymph nodes. The mathematical model described in this work consists of reaction-diffusion equations with a delay. It shows that the different regimes of infection spreading like the establishment of a low level infection, a high level infection or a transition between both are determined by the initial virus load and by the intensity of the immune response. The dynamics of the model solutions include simple and composed waves, and periodic and aperiodic oscillations. The results of analytical and numerical studies of the model provide a systematic basis for a quantitative understanding and interpretation of the determinants of the infection process in target organs and tissues from the image-derived data as well as of the spatiotemporal mechanisms of viral disease pathogenesis, and have direct implications for a biopsy-based medical testing of the chronic infection processes caused by viruses, e.g. HIV, HCV and HBV.The research was funded by the Russian Science Foundation (Grant no. 15-11-00029) to G.B., A.M., V.V. A.M. was also partially supported by a grant from the Spanish Ministry of Economy and Competitiveness and FEDER (Grant no. SAF2013-46077-R). S.T. and V.V. were also partially supported by FONDECYT (Chile) project 1150480. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

ϒ production in p–Pb collisions at √sNN=8.16 TeV

ϒ production in p–Pb interactions is studied at the centre-of-mass energy per nucleon–nucleon collision √sNN = 8.16 TeV with the ALICE detector at the CERN LHC. The measurement is performed reconstructing bottomonium resonances via their dimuon decay channel, in the centre-of-mass rapidity intervals 2.03 < ycms < 3.53 and −4.46 < ycms < −2.96, down to zero transverse momentum. In this work, results on the ϒ(1S) production cross section as a function of rapidity and transverse momentum are presented. The corresponding nuclear modification factor shows a suppression of the ϒ(1S) yields with respect to pp collisions, both at forward and backward rapidity. This suppression is stronger in the low transverse momentum region and shows no significant dependence on the centrality of the interactions. Furthermore, the ϒ(2S) nuclear modification factor is evaluated, suggesting a suppression similar to that of the ϒ(1S). A first measurement of the ϒ(3S) has also been performed. Finally, results are compared with previous ALICE measurements in p–Pb collisions at √sNN = 5.02 TeV and with theoretical calculations