188 research outputs found

    Vampire Attacks: Draining Life from Wireless Ad Hoc Sensor Networks

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    Biochar as a potential carrier for agricultural beneficial microbes

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    © SGEM2018. In the recent years, growing interest to biochar as a means of improving soil quality is observed. Biochar is a product of pyrolysis of biomass such as plant residues or organic wastes. Biochars made of manures are special because they can solve two environmental problems simultaneously – waste reduction and soil fertilization, but they are less studied. In our research, we suggest to improve the properties of biochars derived from manures by means of immobilizing beneficial microbes on them. In this study, the choice of the method of such immobilization was made. Biochar from chicken manure produced at 5000C peak temperature for 3 h was used as a model biochar, and Pseudomonas putida able to suppress soil borne phytopathogens was used as a model microbe. Two types of immobilization in laboratory conditions were used. The first one included spreading of night culture concentrated ~3 fold (final cells amount – about 107 gene copies ml-1) on the surface of biochar in a ratio of 1:1, then drying in sterile conditions for 24 h and packing. The second one included wetting biochar in the culture medium with ~1.5 fold concentrated night culture, shaking for 1 h, then drying in sterile conditions for 24 h and packing. To track the survival rate of immobilized bacteria, scanning electron microscopy as well as quantitative PCR were used. It was shown that bacteria survived similarly after both types of immobilization during the first 10 days, however, later wet immobilization seemed to be more effective, which was proved by higher bacterial gene numbers on that biochar as compared with the dry treated one. We suggest that this is due to deeper penetration of microbes into the pores of biochars while using the wet method

    Hadron Production via e+e- Collisions with Initial State Radiation

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    A novel method of studying e+e- annihilation into hadrons using initial state radiation at e+e- colliders is described. After brief history of the method, its theoretical foundations are considered. Numerous experiments in which exclusive cross sections of e+e- annihilation into hadrons below the center-of-mass energy of 5 GeV have been measured are presented. Some applications of the results obtained to fundamental tests of the Standard Model are listed.Comment: 50 pages, 88 figures, accepted for publication in Rev. Mod. Phy

    Study of the process e+eπ+πe^+e^- \to \pi^+\pi^- in the energy region 400<\sqrt[]{s}<1000 MeV

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    The cross section of the process e^+e^-\to \pi^+\pi^- was measured in the SND experiment at the VEPP-2M collider in the energy region 400<\sqrt[]{s}<1000 MeV. This measurement was based on about 12.4 \times 10^6 selected collinear events, which include 7.4\times 10^6 e^+e^-\to e^+e^-, 4.5\times 10^6 e^+e^-\to\pi^+\pi^- and 0.5\times 10^6 e^+e^-\to\mu^+\mu^- selected events. The systematic uncertainty of the cross section determination is 1.3 %. The \rho-meson parameters were determined: m_\rho=774.9\pm 0.4\pm 0.5 MeV, \Gamma_\rho=146.5\pm 0.8\pm 1.5 MeV, \sigma(\rho\to\pi^+\pi^-)=1220\pm 7\pm 16 nb as well as the parameters of the G-parity suppressed decay \omega\to\pi^+\pi^-: \sigma(\omega\to\pi^+\pi^-)=29.9\pm 1.4\pm 1.0 nb and \phi_{\rho\omega} = 113.5\pm 1.3\pm 1.7 degree.Comment: 30 pages REVTEX and 31 figure

    Extracting Br(omega->pi^+ pi^-) from the Time-like Pion Form-factor

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    We extract the G-parity-violating branching ratio Br(omega->pi^+ pi^-) from the effective rho-omega mixing matrix element Pi_{rho omega}(s), determined from e^+e^- -> pi^+ pi^- data. The omega->pi^+ pi^- partial width can be determined either from the time-like pion form factor or through the constraint that the mixed physical propagator D_{rho omega}^{mu nu}(s) possesses no poles. The two procedures are inequivalent in practice, and we show why the first is preferred, to find finally Br(omega->pi^+ pi^-) = 1.9 +/- 0.3%.Comment: 12 pages (published version

    Formalism for dilepton production via virtual photon bremsstrahlung in hadronic reactions

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    We derive a set of new formulas for various distributions in dilepton production via virtual photon bremsstrahlung from pseudoscalar mesons and unpolarized spin-one-half fermions. These formulas correspond to the leading and sub-leading terms in the Low-Burnett-Kroll expansion for real photon bremsstrahlung. The relation of our leading-term formulas to previous works is also shown. Existing formulas are examined in the light of Lorentz covariance and gauge invariance. Numerical comparison is made in a simple example, where an "exact" formula and real photon data exist. The results reveal large discrepancies among different bremsstrahlung formulas. Of all the leading-term bremsstrahlung formulas, the one derived in this work agrees best with the exact formula. The issues of M_T-scaling and event generators are also addressed.Comment: 37 pages, RevTeX, epsf.sty, 10 embedded figure

    Use of submicron vaterite particles serves as an effective delivery vehicle to the respiratory portion of the lung

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    © 2018 Gusliakova, Atochina-Vasserman, Sindeeva, Sindeev, Pinyaev, Pyataev, Revin, Sukhorukov, Gorin and Gow. Nano- and microencapsulation has proven to be a useful technique for the construction of drug delivery vehicles for use in vascular medicine. However, the possibility of using these techniques within the lung as an inhalation delivery mechanism has not been previously considered. A critical element of particle delivery to the lung is the degree of penetrance that can be achieved with respect to the airway tree. In this study we examined the effectiveness of near infrared (NIR) dye (Cy7) labeled calcium carbonate (vaterite) particles of 3.15, 1.35, and 0.65 μm diameter in reaching the respiratory portion of the lung. First of all, it was shown that, interaction vaterite particles and the components of the pulmonary surfactant occurs a very strong retardation of the recrystallization and dissolution of the particles, which can subsequently be used to create systems with a prolonging release of bioactive substances after the particles penetrate the distal sections of the lungs. Submicro- and microparticles, coated with Cy7 labeled albumin as a model compound, were delivered to mouse lungs via tracheostomy with subsequent imaging performed 24, 48, and 72 h after delivery by in vivo fluorescence. 20 min post administration particles of all three sizes were visible in the lung, with the deepest penetrance observed with 0.65 μm particles. In vivo biodistribution was confirmed by fluorescence tomography imaging of excised organs post 72 h. Laser scanning confocal microscopy shows 0.65 μm particles reaching the alveolar space. The delivery of fluorophore to the blood was assessed using Cy7 labeled 0.65 μm particles. Cy7 labeled 0.65 μm particles efficiently delivered fluorescent material to the blood with a peak 3 h after particle administration. The pharmacokinetics of NIR fluorescence dye will be shown. These studies establish that by using 0.65 μm particles loaded with Cy7 we can efficiently access the respiratory portion of the lung, which represents a potentially efficient delivery mechanism for both the lung and the vasculature

    Функциональные ответы альвеолярных макрофагов, сурфактантный белок D и заболевания легких

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    Functions of alveolar macrophages and surfactant protein D in lung disease.Функциональные ответы альвеолярных макрофагов, сурфактантный белок D и заболевания легких
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