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In this study, 15 bovine viral diarrhoea viruses (BVDV) isolated from the field in Turkey were characterised for their biotype, cloned and eventually analysed for their epitopic composition in terms of glycoprotein E2. Immunoplaque assay, plaque assay, limiting dilution and streptavidin-biotin-peroxidase techniques were used for biotype characterisation, cloning of cytopathic (cp) and noncytopathic (ncp) biotypes and epitope analysis, respectively. While 14 out of 15 BVDV isolates were distinguished as ncp biotype, 1 isolate was found to be containing both biotypes (cp + ncp). According to the reactivity patterns of isolates with 15 monoclonal antibodies, 4 different antigenic groups could be formed. There were no antigenic differences between the isolates derived from the same animal with various time intervals. On the other hand, biotype clones isolated from the same animal exhibited difference in one epitope. This is the first study describing antigenic characterisation of BVDV field isolates in Turkey.

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The coat protein (CP) gene from a necrotic strain of potato virus Y (PVY) has been engineered into two-old Hungarian cultivars, namely cv. Mindenes and Somogyi kifli. The integration of the coat protein gene was confirmed by polymerase chain reaction (PCR) using genomic DNA preparations. The transcription and the expression of the integrated CP gene was followed by Northern and Western blot. The pathogene derived resistance was demonstrated by mechanical inoculation of the trans­formant plants after the transfer of the regenerants into soil. The efficiency of the virus protection varied between different potatoes ranging to complete protection to no protection. All plants were tested in field conditions under the special licence, given the competent authority instructed by the Hungarian gene technology act. In two consecutive years three Mindenes independent transformants proved to be highly resistant against two different strains of PVY in provocative experiment.

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Abstract  

Unstable novel species produced by photolysis of ferrocene (Cp2Fe) isolated in low-temperature matrix were studied by means of the57Fe Mössbauer spectroscopy. On the UV-irradiation of57Fe-enriched ferrocene co-condensed with CCl4 in low-temperature N2 matrix (20 K), unknown high spin ferrous species (I.S.=0.90±0.01 mm/s, Q.S=1.94±0.02 mm/s) were produced as well as ferricinium ion [Cp2Fe]+ (I.S.=0.52±0.01 mm/s, Q.S.=0.0 mm/s). On the annealing, these photoproducts disappeared to reform ferrocene by the reverse reaction in the matrix. The mechanisms of the photochemical reaction were discussed.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: M. P. Felicissimo, J. L. Peixoto, M. S. Barbosa, G. Demortier, J.-J. Pireaux, and U. P. Rodrigues-Filho

Summary  

The purpose of this study was to investigate by PIXE and PIGE the pottery from two archaeological sites located near the Brazil-Bolivia border in Pantanal, an area of natural preservation. The region was inhabited by ancient Amerindian tribes long before the Latin America colonization period and a deep understanding of their environment, cultural attributes and interconnections can only be achieved based on the study of archaeological findings. Multivariate statistical procedures were used to determine similarities and correlations between the analyzed samples and to indicate possible sources of raw material provenience. The results showed that traces of Cr, Cu and Ti and Na/Si and Mg/Si counting ratios were important to distinguish sherds from the archaeological sites MS-CP-71 and MS-CP-61.

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Journal of Thermal Analysis and Calorimetry
Authors: A. V. Markin, Ya. S. Samosudova, N. N. Smirnova, E. A. Tatarinova, A. V. Bystrova, and A. M. Muzafarov

Abstract

In this study for the first time the temperature dependences of the heat capacity C p 0 and enthalpies of physical transitions of carbosilane dendrimers with diundecylsilyl and diundecylsiloxane terminal groups of the fifth generation have been measured using the methods of precision adiabatic vacuum calorimetry and differential scanning calorimetry over the range from 6 to 580 K. In the above temperature ranges the physical transformations have been detected and their thermodynamic characteristics were estimated and analyzed. The standard thermodynamic functions: heat capacity C p 0(T), enthalpy H°(T) − H°(0), entropy S°(T) − S°(0), and free Gibbs energy G°(T) − H°(0) and standard entropies of formation of dendrimers at T = 298.15 K have been calculated over the range from T → 0 K to 580 K. The thermodynamic properties of studied dendrimers have been compared.

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Abstract  

Volatile compounds of iridium(I): (acetylacetonato)(1,5-cyclooctadiene)iridium(I) Ir(acac)(cod), (methylcyclopentadienyl) (1,5-cyclooctadiene)iridium(I) Ir(Cp’)(cod), (pentamethylcyclopentadienyl)(dicarbonyl) iridium(I) Ir(Cp*)(CO)2 and (acetylacetonato)(dicarbonyl)iridium(I) Ir(acac)(CO)2 were synthesized and identified by means of element analysis, NMR-spectroscopy, mass spectrometry. Thermal properties in solid phase for synthesized iridium(I) complexes were studied by means of thermogravimetric analysis in inert atmosphere (He). By effusion Knudsen method with mass spectrometric registration of gas phase composition the temperature dependencies of saturated vapor pressure were measured for iridium(I) compounds and the thermodynamic characteristics of vaporization processes enthalpy ΔH T* and entropy ΔS T 0 were determined. The energy of intermolecular interaction in the crystals of complexes was calculated.

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Abstract  

ADSC with its periodical temperature programs combines the features of DSC measured at high heating rate (high sensitivity) with those at low heating rate (high temperature resolution). In addition, the “reversing” cp effects can be separated from the “non-reversing” latent heat effects. Various periodical temperature programs can be applied. This paper compares the different possible temperature programs and their algorithms for the cp determination for metal, metal oxide and polymer of various properties. Simulated and measured results for various wave shapes and samples are presented. The relevant sample properties and their influence on the measurements are identified and guiding rules for the proper choice of the various experimental parameters are given. Measurements with different samples, performed with the new METTLER TOLEDO STARe-System, are shown and compared with the simulation results. The simulations and the measurements clearly show that the alternating techniques can yield new information about sample properties, but are susceptible to the proper choice of the various experimental parameters.

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Abstract

Using XRY-1C calorimeter, the standard molar enthalpy of taurine was determined to be −2546.2 kJ mol−1 . The reliability of the instrument used was tested by using naphthalene as reference material; and through comparing the molar combustion enthalpy of naphthalene measured with its standard value found in literature, the absolute error and relative error were found to be 4.53 kJ mol−1 and 0.09%, respectively. The melting point and melting enthalpy of taurine were determined by Differential Scanning Calorimetry (DSC), which was found to be 588.45 K and −22.197 kJ mol−1, respectively. Moreover, using the DSC method, the specific heat capacities C p of taurine was measured and the relationship between C p and temperature was established. The thermodynamic basic data obtained are available for the exploiting new synthesis method, engineering design and industry production of taurine.

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Journal of Thermal Analysis and Calorimetry
Authors: I. Paukov, Yulia Kovalevskaya, Irina Kiseleva, and Tatiana Shuriga

Abstract

Low-temperature heat capacity of natural zinnwaldite was measured at temperatures from 6 to 303 K in a vacuum adiabatic calorimeter. An anomalous behavior of heat capacity function C p(T) has been revealed at very low temperatures, where this function does not tend to zero. Thermodynamic functions of zinnwaldite have been calculated from the experimental data. At 298.15 K, heat capacity C p(T) = 339.8 J K−1mol−1, calorimetric entropy S o(&) – S o(6.08) = 329.1 J K−1 mol−1, and enthalpy & o(&) − & o(6.08) = 54,000 J mol−1. Heat capacity and thermodynamic functions at 298.15 K for zinnwaldite having theoretical composition were estimated using additive method of calculation.

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Abstract  

Heat capacity C p(T) of the orthorhombic polymorph of L-cysteine was measured in the temperature range 6–300 K by adiabatic calorimetry; thermodynamic functions were calculated based on these measurements. At 298.15 K the values of heat capacity, C p; entropy, S m 0(T)-S m 0(0); difference in the enthalpy, H m 0(T)-H m 0(0), are equal, respectively, to 144.6±0.3 J K−1 mol−1, 169.0±0.4 J K−1 mol−1 and 24960±50 J mol−1. An anomaly of heat capacity near 70 K was registered as a small, 3–5% height, diffuse ‘jump’ accompanied by the substantial increase in the thermal relaxation time. The shape of the anomaly is sensitive to thermal pre-history of the sample.

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