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Radiolabeled peptides derived from ubiquicidine (UBI) are of great interest for early and highly accurate scintigraphic detection and differentiation of infection and sterile inflammation. In the present work the recombinant antimicrobial peptide UBI18-35 - a fragment of the human natural cationic peptide ubiquicidine - was produced in Escherichia coli for the first time. The insoluble expression of the peptide in fusion with ketosteroid isomerase provided high yield, about 6 mg of UBI18-35 per liter. We developed an approach to produce the antimicrobial peptide UBI18-35, that encompasses inclusion body isolation and size exclusion chromatography. This method could be the basis for industrial biotechnological production of diagnostic system components that are in high demand.

In this paper we study the pressure drop in a hydraulic fracture after shut-in of a water injection well. The pressure transient behavior depends on fracture closure, lateral stress, rock elasticity and fracture fluid leak-off. Under the assumption that horizontal cross-sections of a vertical fracture do not depend on the vertical variable, we formulate a mathematical model which allows for determination of both pore pressure and elastic rock displacements jointly with the fracture aperture and fracture fluid pressure. An analytical consideration is performed for the case of an ideal very long fracture with the same aperture along its full length. In the general case, fracture closure is analyzed numerically.

The paper is devoted to investigation of group properties of a one-dimensional model of two-phase filtration in porous medium. Along with the general model, some of its particular cases widely used in oil-field development are discussed. The Buckley–Leverett model is considered in detail as a particular case of the one-dimensional filtration model. This model is constructed under the assumption that filtration is one-dimensional and horizontally directed, the porous medium is homogeneous and incompressible, the filtering fluids are also incompressible. The model of “chromatic fluid” filtration is also investigated. New conservation laws and particular solutions are constructed using symmetries and nonlinear self-adjointness of the system of equations.

The analytic result for the singlet part of the Adler function of the vector current in a general gauge theory is presented in five-loop approximation. Comparing this result with the corresponding singlet part of the Gross-Llewellyn Smith sum rule (Baikov et al., 2010 [1] ), we successfully demonstrate the validity of the generalized Crewther relation for the singlet part. This provides a non-trivial test of both our calculations and the generalized Crewther relation. Combining the result with the already available non-singlet part of the Adler function (Baikov et al., 2008 [2] , Baikov et al., 2010 [3] ) we arrive at the complete O ( α s 4 ) expression for the Adler function and, as a direct consequence, at the complete O ( α s 4 ) correction to the e + e − annihilation into hadrons in a general gauge theory.

Ionic motion in a solid, both chaotic (self-diffusion, Dsd) and electric-field-sustained (ionic conductivity, σ), is mediated by the chemical nature of the compound, the structure of its crystal lattice, and texture of the material. One of the ways to controlling these characteristics be it for a basic study of the mechanism underlying ion transport or a search for high conductivity ionic conductors, lies in complicating the composition of a chemical compound and development of composites. This report demonstrates convincingly that individual LiOH(DsdrefA, σref), NaOH(Dsd, σref), KOH(Dsd, σref) and H2O, which can hardly be considered as attractive candidates for this purpose because of their low conductivity below 500 K, can be used to advantage as a basis for production of a new family of inorganic, high-conductivity (>10−4 S cm−1) protonic conductors at temperatures in the 500–250 K range. The first members of this family studied thus far were chosen drawing from phase diagrams of the corresponding binary systems, more specifically, crystalline hydrates KOH·H2O(Dsd, σrefA), KOH·2H2O(Dsd, σ), and NaOH·H2O(Dsd, σ) and eutectics KOH + NaOH(Dsd, σrefA), LiOH + 1.5 NaOH(Dsd, σ), and KOH + KOH H2O(Dsd, σrefA). (Symbols in the parentheses, σ, σref and σrefA, refer to, accordingly, the conductivity measured in the present paper, published by other authors, and by the present author; the same applies to Dsd and DsdrefA as the hydrogen self-diffusion coefficients.) We are reporting on the first measurements of the self-diffusion coefficients of all the three types of ions in KOH, of oxygen and hydrogen in NaOH, and of hydrogen in crystalline hydrates and eutectics. The cubic phases of the individual hydroxides have Dsd of hydrogen, ~7 · 10−7 cm2 s−1, which only weakly depend on temperature. The Dsd of hydrogen in crystalline hydrates and eutectics measured in the 470–300-K interval is 10−7–10−9 cm2 s−1, and the activation energy, 0.4–0.5 eV. The dc conductivities of the eutectics exceed by two to three orders of magnitude those following from the Nernst–Einstein relation, and by five to six orders of magnitude, those of the individual starting components. It is suggested that this effect is actually a result of the self-organized micro-heterogeneity of the eutectics.

Systems with two degrees of freedom under the action of non-conservative forces and small linear viscous friction forces with complete dissipation are considered. A limit cycle that exists under specific conditions in the vicinity of an isolated equilibrium of the system is constructed using asymptotic methods in the case of 1:2 resonance. A criterion for asymptotic stability of this cycle is obtained to within equality-type relations. An estimate of the region of attraction of the limit cycle in a truncated system is given. Oscillations of a two-link rod system on a plane in 1:2 resonance are investigated. ©2011

The current status of the Adler function and two closely related Deep Inelastic Scattering (DIS) sum rules, namely, the Bjorken sum rule for polarized DIS and the Gross-Llewellyn Smith sum rule are briefly reviewed. A new result is presented: an analytical calculation of the coefficient function of the latter sum rule in a generic gauge theory in order O(alpha_s^4). It is demonstrated that the corresponding Crewther relation allows to fix two of three colour structures in the O(alpha_s^4) contribution to the singlet part of the Adler function., Comment: Talk presented at 10-th DESY Workshop on Elementary Particle Theory: Loops and Legs in Quantum Field Theory, W\"orlitz, Germany, 25-30 April 2010

Recent studies have revealed that electrochemical activity of solid-state cells is formed by a hydrogenated metal (Pd or Ti) and one of the hydroxide compounds KOH·H2O, KOH + NaOH, and KOH + KOH·H2O (Baikov et al., 2007–2008). Two equimolar eutectics, KOH + NaOH and KOH + KOH·H2O, and chemical compound KOH·H2O are solid superprotonics within the temperature intervals of 360–458, 360–370 and 320–420 K, respectively: their conductivities are above 1 mS/cm, and the activation energies are below 0.4 eV. The anomalies observed in the behavior of the conductivity with temperature correlate with those in the heat capacity in the region of 360 ± 1 K. The isotopic effect (H ⇔ D) of the protonic conductivity for KOH·H2O and the high-temperature form of KOH + NaOH is, on the average, 1.4 ± 0.15. The solid monohydrate NaOH·H2O is a protonic (0.4 mS/cm) in the 300–335 K region with an activation energy of ≈ 0.3 eV. The significance of self-organized microheterogeneity of the solid eutectic KOH + NaOH for high conductivity is discussed. The electrochemical cells Pd|KOH·H2O|C, PdHx|KOH + NaOH|PdOy and Ti|KOH·H2O|C can operate as low-power rechargeable batteries producing an emf of ∼ 1.3 V within the temperature region of 360–420 K.

The destabilization of the stable equilibrium of a non-conservative system under the action of an infinitesimal linear viscous friction force is considered. In the case of low friction, the necessary and sufficient conditions for stability of a system with several degrees of freedom and, as a consequence, the conditions for the existence of the destabilization effect (Ziegler's effect) are obtained. Criteria for the stability of the equilibrium of a system with two degrees of freedom, in which the friction forces take arbitrary values, are constructed. The results of the investigation are applied to the problem of the stability of a two-link mechanism on a plane, and the stability regions and Ziegler's areas are constructed in the parameoter space of the problem.

We report on some technical aspects of our calculation of α s 4 corrections to R ( s ) and the semi-leptonic τ decay width [P.A. Baikov, K.G. Chetyrkin and J.H. Kuhn, Phys. Rev. Lett. 101 (2008) 012002, 0801.1821 ; P.A. Baikov, K.G. Chetyrkin and J.H. Kuhn, PoS RADCOR2007 (2007) 023, 0810.4048 ; P.A. Baikov, K.G. Chetyrkin and J.H. Kuhn, Nucl. Phys. Proc. Suppl. 135 (2004) 243]. We discuss the inner structure of the result as well as the issue of its correctness. We demonstrate recently appeared independent evidence positively testing one of two components of our full result.

Electrochemical activation of heterostructures formed by hydroxide proton and two electronic conductors, with one of them being palladium, initiates formation of protonic heterojunctions PdHx|BaCe0.9Nd0.1O2.9 − y / 2(OH) y and PdHx|KOH·nH2O, where x y n = 0.5 and 1. The equilibrium potential of these heterojunctions relative to the Pd reference electrode is approximately − 0.8 V. The temperature interval within which this phenomenon was studied is 360–450 K for barium cerate and 300–373 K and 300–410 K for the hydrated forms of potassium hydroxide with n = 0.5 and n = 1, respectively. The isotopic effect of the potentials of these heterojunctions with protium replaced by deuterium, both in the electrolyte and in the electrode, was determined as 80 mV for the barium cerate at 425 K, and 105 and 120 mV at 368 K for the potassium hydroxide for n = 0.5 and 1.0, accordingly. The deuterated heterojunction was found to have a more negative potential. The reproducibility of the measurements was better than ± 20 mV. A comparison of the experimental values of the isotopic heterojunction potential shift and of the isotopic effect of the zero-point energies of hydrogen atoms dissolved in Pd and of protons involved in the O–H chemical bonding in the electrolyte lattice suggests that quantum effects contribute to the potential of the hydrogen-solution-in-palladium–proton-conductor-with-hydroxide-ions protonic heterojunction.

We discuss recently obtained four loop results in QCD which all are eventually based on the calculation of four loop massless propagators.

We discuss recent developments in multiloop calculations aiming eventually in computing the total cross section for e^+e^- annihilation into hadrons in order alpha_s^4.

The current status of the higher order QCD corrections to the width of the tau is discussed. We report on the result of the first complete calculation of the quadratic quark mass correction to the correlator of the two currents relevant for the strangeness-changing semihadronic tau-decay rate including its real part at the four-loop level. We discuss phenomenological implications for determination of ms.

We report the results of the first complete QCD five-loop calculation, viz. analytical contribution of order m q 2 α s 4 , to the (absorptive part of) the vacuum polarization function. The contribution directly leads to the knowledge of the the full O ( α s 4 m q 2 / s ) correction to the total cross-section of e+e− annihilation into hadrons. We compare our results with predictions following from various optimization schemes.

Barium cerate (BaCeO 3 ) is a parent material for the family of high-temperature protonic conductors. Nowadays, BaCeO 3 -based materials were accessible in ceramic form. Recently, pure and doped BaCeO 3 were obtained in crystal form, and this gives an ability for more reliable study of microscopic aspects of hydrogen intercalation. This paper is devoted to study the details of proton intercalation process by luminescent and IR absorption spectroscopy. In this study, it was shown for the first time that charge compensation in the process of proton incorporation in undoped barium cerate is provided by mixed valence state of cerium ions.

We present the analytical calculation of the contribution of order m_q^2 \alpha_s^4 n_f^2 to the absorptive part of the vacuum polarization function of vector currents. This term constitutes an important gauge-invariant part of the full O(m_q^2 alpha_s^4) correction to the total cross-section of e^+ e^- annihilation into hadrons. The results are compared to predictions following from various optimization schemes., Comment: The complete paper is also available via the www at http://www-ttp.physik.uni-karlsruhe.de/Preprints/

Thermopower and conductivity are measured for the perovskite-like manganite La1−xBaxMnO3 (0.02⩽x⩽0.35) in the temperature range 200–950°C and oxygen pressure varying between 10−11 and 0.5 atm. The data for thermopower and electrical conductivity indicate a transport mechanism dominated by adiabatic hopes of small polarons. The high-temperature limit for the thermopower is mainly defined by the spin contribution while configurational contribution does not depend essentially on the doping level. Changes in the conductivity with doping are shown to reflect variations in the mobility of charge carriers.

We give a short presentation of the first genuine QCD five-loop calculations, viz. analytical contributions of order αs4nf2 and mq2αs4nf2 to the vacuum polarization function of vector currents. These corrections form an important gauge-invariant subset of the full O(αs4) correction to e+e− annihilation into hadrons.

The integration by parts recurrence relations allow to reduce some Feynman integrals to more simple ones (with some lines missing). Nevertheless the possibility of such reduction for the given particular integral was unclear. The recently proposed technique for studying the recurrence relations as by-product provides with simple criterion of the irreducibility., Comment: LaTeX, 6 pages, no figures, the complete paper, including figures, is also available via anonymous ftp at ftp://ttpux2.physik.uni-karlsruhe.de/ttp99/ttp99-52/ or via www at http://www-ttp.physik.uni-karlsruhe.de/Preprints/

In this paper we present the first data on a single crystal of Gadolinia doped Ceria (CGO). The crystal was prepared using inductive melting in a cold crucible. The cell parameter ( a =5.426 A) was estimated using XRD on a powdered sample. The conductivity was measured by impedance spectroscopy in N 2 , O 2 and air between 190 and 550°C. The activation energy was found to be 1.1 eV. The diffusion and surface exchange coefficients were determined using 18 O isotope exchange and SIMS. The activation energy for the diffusion process was found to be 1.16 eV. A transition in the activation energy of the surface exchange coefficient from low to high was seen at around 650°C.

The implementation of an algorithm for three-loop massive vacuum integrals, based on the explicit solution of the recurrence relations, in REDUCE and FORM is described., LaTex, 12 pages, no figures

New data on the hydrogen behavior in barium cerate and strontium cerate and titanate have been obtained. The conclusions on the chemical state of hydrogen in cerates are drawn from the physico-chemical data on gas–solid exchange phenomena. The idea of different states of hydrogen in the same lattice is advanced. Both earlier and new data on the properties of alkaline hydroxides and hydrogenated Ba 2 YCu 3 O 7 were used for a deeper understanding of the hydrogen behavior in the high-temperature proton conductors.

An impedance spectroscopic investigation on a Gd-doped BaCeO 3 single crystal is reported in which the electronic and ionic properties of the material have been studied systematically between 800 °C and 1200 °C under well defined oxygen partial pressures. For the first time, the conductance, the diffusion coefficients and the concentrations of the individual defects in a single crystal have been determined as a function of temperature and oxygen partial pressure. The ionic transport numbers are calculated in the light of the conductivity data. The defect structure of the material is discussed in the framework of point defect chemistry and the quasi-chemical reaction constants are determined. Based on the data acquired, the electron holes are suggested to be large polarons, whereas the electrons are small polarons.

Explicit formulas for the solutions of the recurrence relations for 3--loop vacuum integrals are suggested. This formulas can be used for direct calculations and demonstrate a high efficiency. They also produce a new type of recurrence relations over the space--time dimension., 5 pages, misprint in the intermediate formula corrected

Using the copper Nuclear Quadrupole Resonance (NQR) spectra of RE Ba 2 Cu 3 O 6+ x (RE123, REY, Nd, La, 0 ≤ x ≤ 1) we have determined the relative intensities of the resonance lines belonging to the Cu(1) sites in the Y123 structure type with two, three and four nearest neighbor oxygens as a function of the oxygen concentration x . The different intensity distribution for different RE shows that, unlike the case in Y123, where the oxygen ions in the basal plane order preferentially into long chain fragments leading to the formation of the ortho-II structure at 0.5 x x = 0.5 and oxygen vacancies above this value tend to be single, forming near x = 0.5, most probably, the “herringbone” structure. Due to different oxygen order, the Nd123 and La123 become superconducting only at high oxygen contents, x ≥ 0.6, whereas at lower x the systems show the antiferromagnetic order in the Cu(2) planes, detected by the zero field nuclear magnetic resonance spectra of the Cu(2) sites and by muon spin rotation experiments.

From 18O-tracer diffusion, 1H-PFG-NMR and conductivity measurements, the diffusivities of protonic defects (OH0) and oxygen ion vacancies (Vo−1) in BaCeO3 single crystals doped with gadolinium and yttrium have been determined. Their dependence on the nature and concentration of the dopant, and the degree of hydration provide evidence for (i) a strong relaxation around oxygen ion vacancies which decreases with increasing vacancy concentration and (ii) the absence of significant defect interaction even for high dopant concentrations. The attempt frequencies are consistent with a proton diffusion mechanism assisted by the local oxygen dynamics. The thermodynamic data for the hydration reaction, including the water solubility, are in accordance with the conclusions drawn from the transport data. The hydration enthalpy is suggested to be determined not only by the formation enthalpy of oxygen ion vacancies but also by the basicity of the oxygen.

The two-step procedure for preparing yttrium-barium cuprates described by the general formula H 2m + h Ba 2 YCu 3 O 6.5 + m+d' ( m = 0; 1; 2, h ≥ O , d ≤ l ), is considered. The kinetic of hydrogen charging Ba 2 YCu 3 O 7 and the oxidation of hydrogenated samples is described. The proton migration in the bulk and hydrogen exchange with a gaseous phase have been studied by the isotope exchange method. The diffusion coefficient of hydrogen at 470 K is estimated to be 10 − 8 cm 2 s − 1

New compounds of the general composition REBa 2 Cu 3 O 6 (OH) x , 1.5 < x < 2 have been synthesized by treating the hydrogen loaded 123 compounds with oxygen. They have been characterized by X-ray diffraction, susceptibility, and NMR and NQR of Cu. The compounds are pseudocubic with the same cation sublattice as the starting 123 compounds. They are at the limit between superconductivity and antiferromagnetism and show a well defined nonsymmetric EFG at the Cu(I) sites different from the EFG tensors in the starting compounds and in samples loaded only with hydrogen

The antiferromagnetic compounds produced by the reaction of the 123 and 124 HT c superconductors with hydrogen are studied by nuclear resonancee of copper. For the 123 compounds two reactions are possible, the reduction by hydrogen which leads to the normal antiferromagnetic YBa 2 Cu 3 O 6 , and the solution of hydrogen in YBa 2 Cu 3 O 7 which forms a different antiferromagnetic structure with hydrogen concentration of more than 2 H mol −1 . Both structures can be distinguished by the nuclear quadrupole resonance spectra of the Cu(1) sites and the nuclear magnetic resonance spectra in the hyperfine field of the antiferromagnetic state. By using samples containing Gd at the place of Y we can prove that only the Cu(2) sites carry permanent magnetic moments. In the hydrogen loaded YBa 2 Cu 4 O 8 the situation is similar with the antiferromagnetic order limited to the Cu(2) sites.

The equations of motion of two linear periodic chains of non-linearly interacting particles are considered in the long-wave approximation. The system of equations obtained is a model for describing wave processes in two-component media. Methods of group analysis (see, for example, [1]) are used to pick out the submodels that admit of the largest group of point mappings. Particular invariant solutions are presented resented for two submodels with obvious mechanical interpretations. It is shown that, if the potential of the non-linear interaction can be expressed as a harmonic function of the relative displacement of particles in the chains, and the acoustic velocities of non-interacting chains are different, the system is a special type of soliton filter; the allowed soliton velocities are determined. A few solutions describing the long-wave dynamics of the system are presented, assuming the presence of additional shear forces.

The incorporation and migration of protons in Y-doped BaCeO 3 crystals is studied, using room temperature infrared (IR) measurements and electrical conductivity measurements in the temperature range 25–250°C. The IR spectra of crystals pretreated at high temperature in H 2 O-saturated gas show two very broad OH bands at 3383 cm −1 and 3035 cm −1 . The OH bands are fully replaced by OD bands, at 2503 cm −1 and 2283 cm −1 , upon treatment in D 2 O-saturated gas. The conductivity of the H + -charged sample is two to three times that of the D + -charged sample in the temperature range studied, and the activation energy of the H + -charged sample (0.60 eV) is 0.05 eV lower, suggesting non-classical proton hopping.

Formation of thin supported iron oxide films from oleic acid stabilized Fe3O4 sols in decane medium has been studied using thermogravimetry, X-ray and electron diffraction, transmission electron microscopy, Mossbauer spectroscopy and chemical analysis. The continuous transparent films prepared by casting the sols over a flat substrate with subsequent heating in the air at 420–820 K were from 50–60 nm up to 1.5 μm thick, consisting of colloid-size particles. Intensive particle growth has been observed only above 670 K after complete removal of the dispersion medium and the stabilizer. The films had a crystal structure of magnetite on heating below 570 K, γ−Fe2O3 between 620 and 670 K and α−Fe2O3 above 670 K.

The isotopic method has been used to measure the concentration of hydrogen in as-prepared (Ba, Sr)CeO 3 and (Ca, Sr, Ba)TiO 3 samples. Hydrogen concentrations in the range 0.007 to 0.04 of H per formula unit have been detected for undoped samples, and even more for doped specimens. The influence of cation composition, dopant number density, and preparation method is analyzed. Thermal desorption studies and comparison of hydrogen and oxygen mobilities have been utilized to analyze the state of the dissolved hydrogen.

The structure and properties of hydrogen-doped amorphous carbon (a-C : H) films are determined by the hydrogen content and the structure of the hydrogen bonding with the lattice. Study of the thermal effusion of hydrogen (TEH) provides information concerning both the thermal stability of the films and the chemical bonding of hydrogen. Wild and Koidl [1] measured the TEH in a-C : H films as a function of the bias potential V b . They found that as V b was increased from 50 to 500 V, the TEH threshold temperature increased from 300 to 600 °C. In a study of the thermal stability of a-C : H films prepared by glow discharge, Watanabe and Okumura [2] observed that on heating to 350 °C the thickness and optical gap of the films decreased and at still higher temperatures the films decomposed. Nadler et al . [3] investigated the thermal annealing effect in films prepared by the decomposition of hydrocarbons. On annealing at 500 °C, they observed hydrogen effusion from sp 3 states and formation of C=C bonds, accompanied by a decreased transparency of the films. In an investigation of a-C : H films prepared by r.f. glow discharge, we observed changes in the structure of the amorphous network and of the hydrogen bonding with the lattice as well as in the electronic properties of such films [4]. The data obtained suggest that TEH occurs differently in a-C : H films of different structures. Therefore it would be of interest to experiment on the TEH in a-C : H films.

Coefficient functions of the operator G 2 in the large mass expansions of correlators of two (pseudo) scalar and (pseudo) vector currents are calculated in the two-loop approximation. The obtained results are numerically sizeable and could be important for the phenomenological determination of the value of the corresponding condensate 〈 G 2 〉.

The stability of the motion of the boundary between two visco-elastic liquids in a porous medium caused by the non-equilibrium of filtration fluxes is investigated. Two stages in the development of the instability are considered: the first is the development of small perturbations on the surface of the initially unperturbed displacement front and the second is the evolution of small perturbations on the surface s of “fingers” of displacing liquid extruded after the development of the first-stage instability. The theoretical analysis shows that the use of visco-elastic liquids for displacing oil from strata should increase the stability of the displacement process. In the case of visco-elastic liquids with relaxation along the pressure gradient the stability of the displacement is due to stabilization of the actual boundary between the liquids, whereas with relaxation along the flux it is achieved because of the instability of the “fingers” of displacing fluid.

The authors have measured the coefficient of translational diffusion D0, the sedimentation coefficient S0 and the intrinsic viscosity [η] of samples and fractions of polyvinylpyrrolidone in 0.1 M sodium acetate solution in the interval MW 2 ⩽ M × 10−3 ⩽ 2200. In the region M > 4 × 104 they obtained the relation: [η] = 8.86 × 10−5M0.74; D0 = 2.42 × 10−4M−0.58 and S0 = 2.14 × 10−15M0.42. In the region M⩽4 × 104: [η] = 5.0 × 10−4M0.56, D0 = 1.29 × 10−4M−0.52 and S0 = 1.15 × 10−15M0.48. The values of the hydrodynamic invariant A0 = (3.2 ± 0.25) × 10−10 erg degree−1 mole13, sedimentation parameter βs = (1.3 ± 0.17) × 107mole13, temperature viscosity coefficient negative: Δ ln [η]/ΔT = −6.3 × 10−3 degree−1. From the theory of the hydrodynamic properties of a worm-like necklace taking into account the influence of the effects of excluded volume an evaluation is made of the equilibrium rigidity A and the hydrodynamic diameter d of the chains modelling the macromolecules in solution. The evaluations of A agree with the values obtained from the Burchardt-Stockmayer-Fixman and Cowie-Bywater constructions: A = (2.1 ± 0.3) nm, d = (0.5 ± 0.13) nm.