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Equine viral arteritis (EVA) is a contagious disease of equids caused by equine artheritis virus (EAV), widespread in most countries in the world, where patients are diagnosed. The infection usually starts asymptomatic. Clinical signs indicate respiratory infection of different intensity and also abortions are present at different stages of gestation. Large prevalence of this disease in the world has become a growing economic problem. The disease is specific to a particular kind of animals, and it affects only equids (horses, donkeys, mules, mule and zebras). In countries where the infection has been confirmed, the percentage of positive animals differ. Likewise, there is difference in percentage among certain animal kinds. The highest percentage of positive animals has been found in totters and the lowest in cold-blooded.

Fast and accurate computation of thermo-physical properties is essential in computationally expensive simulations involving fluid flows that significantly depart from the ideal gas or ideal liquid behavior. A look-up table algorithm based on unstructured grids is proposed and applied to non-ideal compressible fluid dynamics simulations. The algorithm grants the possibility of a fully automated generation of the tabulated thermodynamic region for any boundary and to use mesh refinement. Results show that the proposed algorithm leads to a computational cost reduction up to one order of magnitude, while retaining the same accuracy level compared to simulations based on more complex equation of state. Furthermore, a comparison of the LuT algorithm with a uniformly spaced quadrilateral tabulation method resulted in similar performance and accuracy.

The cell membrane of ram spermatozoa is more sensitive to the freezing process than in other species due to its composition. As a result, the quality and viability of frozen thawed ram spermatozoa are often poor, which together with the specific structure of the ewe's cervix are the main reasons for lower fertility in ewes after intracervical insemination. In the present study we investigated the effects of semen centrifugation through a single layer of a species-specific colloid (Androcoll-O) on post-thaw quality of ram spermatozoa. Motility, viability and morphology were analysed 0, 6, 12 and 24 h after thawing. DNA fragmentation index (%DFI) of the samples was assessed 0 h after thawing, by SCSA™. Membrane and acrosome integrity of spermatozoa were analysed by Sybr-14/PI/PNA test 0 h after thawing. The proportion of motile spermatozoa was significantly higher in SLC - selected samples in comparison to control (not SLC - selected) samples at 0, 6, 12 (P

The most frequent problems in horses reproduction are generally divided into those of infectious and non infectious etiology. Common causes of infectious diseases are usual­ly viruses and bacteria, and less frequently protozoa, mykoplasma and fungi. In this work there are presented the most important fact about sexually transmitted diseases, their clinical picture, risk factors, preventive measures as well as measures to prevent and eradicate the diseases. The biggest risk factor for sexually transmitted diseases in horses are breeding stallions, both in natural mating and in artificial insemination. Therefore, in order to prevent genital infections in horses, it is essential that the stallions used for breeding are healthy (non-infected). That can be determined with certainty only if the stallions are examined (tested) just before the breeding season on most frequent sexually transmitted diseases (CEM,EAV). It is well known that in most cases the clinical picture of sexually transmitted diseses is not manifested on genitals. As well, variations in clinical picture can be expected also in mares, depending on the stage of the disease and its etiology. Harms arising from sexually transmitted diseases can be divided into direct and indirect. Direct damage occurs in the form of endometritis, miscarriage, stillbirths and births of weak foals, and indirect in restricting the traffic of infected and suspicios animals, isolation of the infected ones as well as medical treatment and interrupting mating.

Summary Reasons for performing study The interest in donkeys is growing due to their integration in the systems of ecological farming, among other reasons. Objectives Due to limited reports on leptin concentrations in donkeys, the aim of the present study was to examine age-dependent and seasonal changes in the circulating leptin concentration in female donkeys (jennies) and thus contribute to knowledge about the physiological characteristics of this species. Study design Prospective longitudinal study. Methods The study was performed over a year (September 2008 to September 2009) on 20 yearling and young adult (pregnant, lactating or barren) jennies aged 1–5 years at the onset of the study; the animals were kept on pasture from May to September and stabled for the rest of the year. Blood samples were taken monthly and analysed for serum leptin concentrations by a commercial radioimmunoassay kit. Results Circulating leptin concentrations in studied jennies were lower than those reported for donkeys and horses. Despite the tendency for lower values in yearling vs. young adult jennies, the age range of the examined animals was insufficient to confirm any age-related leptin variations. Significant seasonal leptin fluctuations with peak levels in late spring and the lowest levels in autumn months, correlated with photoperiod, were detected in yearling, barren as well as pregnant jennies. Therefore, it was impossible to identify any effects of gestation or lactation on leptin concentrations of jennies. Conclusions The results of this study cannot be used as evidence of a causal relationship between the photoperiod and seasonal circulating leptin fluctuations in donkeys, but could reflect changes induced by various external or internal factors enabling adaptations of grazing animals in variable submediterranean environments.

One of the features of apoptosis is the externalization of phosphatidylserine which could be used to remove apoptotic cells from semen preparations. Magnetic-activated cell sorting using annexin V-conjugated microbeads which bind to phosphatidylserine could be used to enhance semen quality. Twelve boar semen samples after 3 days of liquid storage at 16­­–17 °C were subjected to magnetic-activated cell sorting. Bound and unbound fractions and control samples were subjected to flow cytometry following the staining of spermatozoa with Annexin V conjugated with Alexa Fluor 488 and propidium iodide. Four subpopulations were obtained: live, early apoptotic live, late apoptotic, early necrotic dead and late necrotic dead. The frequency of early apoptotic and late necrotic spermatozoa was significantly higher (P< 0.05) in bound (14.1 ± 10.6% and 24.1 ± 10.2%, respectively) than in unbound fractions (3.4 ± 2.1% and 12.7 ± 3.1%) and control (3.5 ± 1.6% and 12.0 ± 5.0%). The lowest concentration of live spermatozoa was found in the bound fraction (10.6 ± 8.0 %), which differed significantly (P< 0.05) from the control. In unbound fractions there was a significantly higher concentration (P< 0.05) of morphologically normal spermatozoa (31.8 ± 12.6%) compared to bound ones (5.9 ± 7.3%). A significantly (P< 0.05) lower proportion of morphologically normal spermatozoa was observed in both fractions compared to control (67.2 ± 17.0%). Boar spermatozoa were separated by the above method for the first time, however, the results showed this method to be inappropriate for boar semen separation under the tested conditions.

The objective of this work was to examine linear thermal expansion of virgin and poled 0.57Pb(Sc 1/2 Nb 1/2 )O 3 –0.43PbTiO 3 ceramics between 30 °C and 600 °C by contact dilatometry. The thermal expansion dL / Lo of the virgin ceramic increases with increasing temperature until approximately 260 °C. The physical and technical thermal expansion coefficients were determined. At 260 °C the physical thermal coefficient is 2.08 × 10 −6 K −1 . Between 260.0 °C and 280.0 °C an anomaly in the thermal expansion vs. temperature and an endothermic peak in the differential scanning calorimetry curves correspond to the phase transition region from tetragonal to cubic phase. At temperatures from 280 °C to 600 °C the thermal expansion dL / Lo increases again. In the derivative of the dL / Lo heating curves of the poled ceramics, additionally to the anomaly at 270 °C, also the anomaly at 160 °C is observed, which is associated with the depolarization of the material during heating.

This study shows the fabrication of lead magnesium niobate-lead titanate (PMN–PT) thick-films by inkjet printing on ceramic substrates for the first time. PMN–PT powder, prepared by mechanochemical synthesis, is dispersed in an organic solvent using a three roll mill to form a high-viscosity paste. For printing, the paste is thinned to a low-viscosity ink. Small amounts of ethyl cellulose in the ink prevent sedimentation. Glass particles are added to the paste to improve adhesion on the substrate surface. A two step inkjet-printing process forming homogeneous layers is introduced. After sintering at 950 °C for 2 h, piezoresponse force microscopy (PFM) is used to investigate the piezoelectric response of the printed films.

The delafossite CuAlO2 powder was prepared from the nano-boehmite AlOOH·xH2O and Cu2O by the solid state synthesis at 1100 °C in argon. The inherently slow solid state reaction was accelerated by introducing rod-like boehmite nano-particles which fully covered the 1 μm sized Cu2O particles in the reactant mixture, and decomposition of the nano-boehmite upon calcination. In contrast, the reaction between the Cu2O and Al2O3, introduced as a reference, resulted in mixed phases under the same experimental conditions. Sintering of the nano-boehmite derived CuAlO2 powder compact at 1100 °C for 2 h in air resulted in the delafossite ceramic with 86% of theoretical density, without any impurities detectable by X-ray diffraction analysis. The analysis of the microstructure by scanning electron microscopy confirmed that the bulk of the sintered sample was delafossite phase with uniformly distributed porosity, with only traces of Cu-rich impurities at the surface.

Direct measurements of the electrocaloric effect (ECE) in bulk lead-free relaxor K0.5Na0.5NbO3-SrTiO3 (KNN-STO) ceramics sintered in air have been performed by using electrocaloric thermometry, i.e., a high-resolution calorimetry with a small modification to the experimental setup and software. The obtained results confirm the existence of a large ECE in this material in the vicinity of the ferroelectric phase transition, where the electrocaloric temperature change ΔT EC around 0.5 K was achieved under a field of 80 kV/cm. At room temperature ΔT EC is comparable with that observed in lead-based ceramic materials, so far the most studied electrocaloric materials, which, however, are less environmentally friendly due to the toxicity of lead.

The mechanism of the mechanochemical reaction between Na 2 CO 3 and Nb 2 O 5 , particularly the reaction course, was explored in detail. New data on the transitional (intermediate) phase of the reaction were obtained, including the characteristics of Nb―O bonding and chemical environment of Na + ions. This was achieved by using analytical methods sensitive to the short-range (local) structural order, i.e., Raman and solid-state NMR spectroscopy. The paper demonstrates the importance of selecting a combination of appropriate analytical tools; through the example of mechanochemistry, we show these tools provide far enriched information on complex reaction mechanisms, like those encountered during processing involving amorphous phases.

This work studies the impact of adding nanoparticles to high-k PMNT (lead magnesium niobate–lead titanate, Pb(Mg0.33Nb0.67)0.65Ti0.35O3) thin films. PMNT thin films were grown on Pt(111)/TiO2/SiO2/Si substrate using a sol–gel technique. Ligand stabilised PMNT nanoparticles were added to the sol–gel material with the aim of seeding the crystallization process. The measurements show that use of nanoparticles in PMNT thin films influences the remanent polarization, coercive field and dielectric constant. These characterization results support the ongoing investigation of the material ferroelectric and electrical properties which are necessary before the novel dielectric can be used in silicon applications.

Electrocaloric effect (ECE), i.e., a reversibly change in the temperature of an electrocaloric material due to the adiabatically applied electric field, is very attractive phenomenon due to its applications, for example in electric refrigeration. The first observations of the giant ECE were based on indirect measurements of the electric polarization and not on direct measurements of the ECE itself. By using direct measurements of ECE we show existence of the giant ECE in PMN ceramics near the electric field-induced ferroelectric phase transition.

The giant electrocaloric (EC) effect is of great importance for application in cooling or heating devices of new generation, which would be friendlier for environment. Recent predictions of the existence of the giant EC effect in polymeric and inorganic ferroelectric relaxors are based solely on the indirect measurements of the electric polarization and not on a direct measurement of the EC effect itself. Here a method and analysis of direct measurements of the giant EC effect in various soft and solid ferroelectric materials in the form of thick and thin films is presented. The field dependence of the EC effect is shown for PbMg1/3Nb2/3O3 (PMN) ceramics and P(VDF-TrFE) (68/32 mol%) copolymers.

Summary Reasons for performing study: The onset of puberty and duration of seasonal cyclicity in Lipizzan fillies and young mares have been determined mostly by empirical data, but very little is known about the hormonal changes at puberty and during the seasonal cyclicity in this breed. Objectives: To determine the onset of puberty and the course of the cyclicity in young Lipizzan mares from age 1–4 years. Methods: Blood samples were collected twice a month for 2 years from 46 Lipizzan fillies age 1–4 years. Progesterone concentrations, indicating ovarian activity, were measured using an EIA kit. Values above 6.4 nmol/l were taken to indicate luteal phase and those below 3.4 nmol/l, oestrus. Results: Fifty percent of Lipizzan fillies entered puberty during the first spring after their birth at mean ± s.e. age 15.25 ± 0.31 months and 50% during the second spring, at age 25.2 ± 0.57 months. For several fillies of all ages, manifesting anoestrus during the winter months, the oestrus started in March and reached a peak in June to September. The duration of the oestrus activity was age-dependent, at 2.37 ± 0.62 months in yearlings and 8.56 ± 0.46 months in fillies age 4 years. In December, >50% of fillies age 2–4 years still exhibited oestrus activity and some entered anoestrus in January the following year. A small proportion of fillies age 3–4 years remained cyclic during the whole year, indicating that factors other than photoperiod can be involved in regulating seasonal cyclicity. Conclusions and potential relevance: Our results demonstrate the influence of seasonal factors on the onset of puberty and on the course of oestrus activity in the majority of Lipizzan fillies. However, certain exceptions were also demonstrated but reasons for the prolonged periods of oestrus activity in some Lipizzan fillies were not identified, and the role of the hormone leptin should be studied in future investigations.

Summary Reasons for performing study: The success rate of artificial insemination following the freezing of stallion semen is limited; therefore, improving the stallion semen quality after the freezing and thawing process is a necessary objective. Objectives: To investigate the influence of glass bead column separation on the freezability of stallion semen. Hypothesis: Glass beads in a column separator remove damaged and dead spermatozoa in the ejaculate during centrifugation. Methods: In total, 50 ejaculates from 6 Lipizzaner stallions were studied. Each ejaculate was divided into 2 parts, one half processed following standard procedure and the second half used for the column separation procedure. After freezing, semen quality was evaluated using standard tests for motility, morphology and viability of semen. Results: Motility and progressive motility of the column-separated (CS) semen were significantly higher (P

Matrix metalloproteinases were detected in reproductive tissues and seminal plasma of various animal species. The aim of this study was to determine for the first time the presence of gelatinases and metalloproteases in boar seminal plasma and to correlate the results with semen indicators. Gelatin zymography was used for simultaneous identification and measurement of gelatinase enzyme activity associated with their molecular weights. Several gelatinase forms were identified in seminal plasma of boars. Those that were stimulated by CaCl2 and inhibited by EDTA and phenanthroline were considered as metalloproteases. Negative correlation between semen indicators (sperm index, sperm concentration and concentration of progressive motile sperm) and the concentrations of metalloprotease at 78 kDa and 66 kDa means that higher values of semen indicators correlate with lower concentrations of these metaloproteases in seminal plasma. Gelatinases with molecular weight of 225, 78 and 66 kDa correlated with higher levels of acrosome damage. Samples with sperm index above 110 M/ml contained gelatinases of significantly lower band intensities at 78 and 66 kDa compared to samples with SI less than 110 M/ml. Bands with 225, 78 and 66 kDa are suggested to belong to a dimer of MMP-9, proMMP-2 and mature MMP-2.

We studied the synthesis of lanthanum zirconate from lanthanum nitrate and zirconium butoxide in the transition from liquid to amorphous and crystalline phase. Thermal behaviour of lanthanum nitrate dissolved in 2-methoxyethanol is different from that of the salt, which we ascribe to the potential coordination of the solvent to lanthanum atoms. IR analysis shows that lanthanum nitrate remains strongly associated in the solvent. The lanthanum environment in the lanthanum nitrate and lanthanum zirconate sols, determined by EXAFS, is similar to that of the lanthanum nitrate hydrate. The environment is completely changed in the dried lanthanum zirconate precursor powder and powder heated at 500 °C due to the decomposition of nitrates. Zirconium species form polynuclear oxo-alkoxide complexes during thermolysis and they are stable from room temperature to 500 °C. The powder heated up to 700 °C for 1 h is amorphous, while after heating at 800 °C for 1 h pure pyrochlore phase crystallizes. No link between La and Zr species is established either in the sol or in the dried precursor powder or amorphous powder heated at 500 °C. The reaction between the metallic species proceeds as a solid-state reaction. The synthesis route ensures a very good mixing of the species at the nanometre level.

Phonons in K 0.5 Na 0.5 NbO 3 (KNN-50) ceramics were investigated from 10 to 900 K by means of Raman, infrared and THz spectroscopy. A first-order phase transition was detected from cubic to tetragonal phases at about 710 K, when the first component of the polarization appears. Transition from the tetragonal to the orthorhombic phase takes place around 475 K. The last transition from orthorhombic to rhombohedral phases is strongly first order. T C is about 90 K in KNN-50. All Raman active modes below 100 cm− 1 disappear. An overdamped soft mode present at high temperatures in the THz range changes its dielectric strength at each phase transition (when the corresponding component jumps to higher frequencies) and abruptly disappears in the rhombohedral phase. However another excitation at lower frequency than the phonons is needed to explain the static value of the permittivity.

We have studied the influence of increasing the amount of β-spodumene (LiAlSi2O6), as a Li2O-containing flux, on the phase composition, the microstructure evolution and the physical properties of high-alumina porcelain. Quartz reacts with β-spodumene in the temperature range 1150–1250 °C, forming lithium aluminium silicates with a larger amount of SiO2. The presence of lithium minerals contributes to a lower CTE for the fired bodies. At 1300 °C an improved flexural strength is achieved with compositions containing 1.0 or 1.2 wt.% of Li2O, as a result of a more uniform microstructure. With increasing amounts of Li2O the overfiring effect is greatly enhanced. The most favourable characteristics from an industrial perspective with regard to flexural strength and deformation during firing were attained by using a high-alumina porcelain composition containing 1.0 wt.% Li2O.

Cows in negative energy balance exhibit reduced fertility, mediated by metabolic signals that influence the reproductive system. Measurement of IGF-1 contributes to the diagnosis of negative energy balance. The aim of this study was to investigate possible variations in IGF-1 levels in samples taken at different times of the day. Equine IGF-1 ELISA was used for measuring IGF-1 in bovine samples. Statistical analysis was applied to the results. Using scatter diagrams fitted with Deming regression lines, we established that paired measurements on samples obtained at different times were close to the line of equality. 90% of the absolute differences were less than the reproducibility coefficient, confirming that the level of agreement between the IGF-1 levels at different times of the day was satisfactory. IGF-1 levels in bovine samples were independent of the time of day at which samples were taken.

The fabrication of piezoelectric transducers for high resolution medical imaging applications requires a backing material to damp the piezoelectric resonance, resulting in a shorter time response, i.e. improved resolution, but lower sensitivity. Thus, the choice of such a substrate must be made according to its acoustical properties, namely the ratio of acoustic impedance of the backing material and the piezoelectric layer. Moreover, this backing material must have a relatively high attenuation, and provide good surface properties such as a low roughness and diffusion potential. Finally, the substrate material must have a good mechanical behavior at high temperature (around 900°C for the sintering of the piezoelectric thick film). In this context a review of available materials is first given, and the corresponding list is found to be quite limited. Several PZT/PGO piezoelectric thick films deposited by screen-printing have been fabricated on dense alumina [1] and have delivered good electromechanical per...

We investigated the grain size effect on the high temperature behaviour of PMN-35PT ceramics around the tetragonal–cubic phase transition using second harmonic generation (SHG) and dielectric spectroscopy. Our data revealed coexistence of the first-order ferroelectric phase transition and relaxor behaviour in the coarse grain (grain size ∼4 µm) µ_PMN-35PT. The phase transition is hindered and relaxor features prevail in the fine grain (grain size ∼150 nm) n_PMN-35PT ceramics. Effect of the grain-size reduction on the SHG and dielectric response could be attributed to stabilisation of intermediate domain configurations between the frozen polar nanoclusters and large ferroelectric domains and to the enhanced stability of polar nanoclusters in the fine grain ceramics.

Polar phonons in infrared spectra of (Pb0.88La0.08 0.04)(Zr0.65Ti0.35)O3 ceramics and thin films exhibit similar behaviour. Each phonon allowed in perfect cubic lattice is split not only below the Burns temperature T B = 620 K, where it can be explained with breaking of cubic symmetry in polar nanoclusters, but also above T B. We explain it with two chemical species at both A and B perovskite sites. The E component of the soft mode remains heavily damped at all temperatures and its frequency near 35 cm−1 is almost temperature-independent. The A1 component of the soft mode remarkably hardens below T* ≈ 500 K from 50 to 85 cm−1 and moreover a new mode activates in IR spectra below 300 K at frequencies between A1 and E soft modes. Based on comparison with other relaxors, we conclude that such behaviour is general for all relaxor ferroelectrics with perovskite structure.

The thin films of potassium sodium niobate (K 0.5 Na 0.5 )NbO 3 on Pt(111)/TiO 2 /SiO 2 /Si substrates have been prepared by chemical solution deposition. The stoichiometric sols were synthesized from corresponding alkali metal ethoxides or acetates and niobium ethoxide in 2-methoxyethanol. The thin film quality is affected by choice of alkali metal precursors. Thin films prepared from the acetate-based sol upon heating to 670°C crystallize in pure perovskite phase. The dielectric permittivity of the 350 nm thick KNN film at 10 kHz is 533 and the dielectric loss factor is 0.068.

Nanocrystalline powders synthesized by mechanochemical activation were successfully used to process high-density submicron- and nanostructured 0.8Pb(Mg 1/3 Nb 2/3 )O 3 –0.2PbTiO 3 perovskite phase ceramics by hot pressing, with average grain size ranging from 0.36 μm down to 88 nm. These materials are very suitable for studying the size dependence of the properties across the submicron range approaching the nanoscale. This is the first report of such a series of ceramic materials of a relaxor-based morphotropic phase boundary composition, and of its properties as a function of the grain size.

The sol–gel deposition method has been successfully applied to obtain Pb(Zr0.2Ti0.8)O3 thin films on platinized silicon wafers. Addition of different amounts (7–15 wt.%) of organic macromolecular polyvinylpyrrolidone in the precursor solution prior to spin coating proves to be an excellent method for obtaining porous films. The crystal structure of as deposited films was analyzed by X-ray diffraction. The porous films show perovskite phase after annealing at 650 °C. The surface morphology has been studied by Atomic Force Microscopy and Scanning Electron Microscopy. The surface profile indicates a roughness of the film of 5 nm and no microcracks on the surface. The ferroelectric behavior was proved for each film, by hysteresis loops and by the “butterfly” shape of the capacitance–voltage characteristics. The remnant polarization and the coercive field decrease while the amount of added PVP increases.

An anomaly in the magnetic susceptibility has been observed at and below the paraelectric – ferroelectric transition in polycrystalline Pb(Fe1/2Nb1/2)O3. The results are indicative of magnetoelectric coupling of the form P2M2. The non-linear relation between the induced magnetization and the applied magnetic field demonstrates the presence of large superparamagnetic clusters embedded in a paramagnetic medium over the whole ferroelectric phase, i.e. far above the antiferromagnetic transition temperature T N .

Determination of boar sperm concentration using a photometer is used routinely by many artificial insemination (AI) laboratories. The agreement between determining sperm concentration using Makler chamber and a photometer has been assessed. Method agreement was evaluated on the basis of scatter plots with Deming regression line, absolute bias plots with limits of agreement, and relative bias plots. Coefficients of variance for the Makler chamber and a photometer were calculated as 6.575±3.461% and 1.635±0.632%, respectively, showing acceptable precision for both methods. The estimated Deming regression equation indicates that the points are close to the line of equality, and the SE of the slope (0.0600) indicates that there is almost no pivoting of the line about the central point through the means of x and y. The estimated intercept for the regression line (4.7069 M/mL) does not differ greatly. Average absolute bias was close to zero at -1.092±15.237 M/mL. Sperm counts obtained with the Makler chamber and photometer agree; 90% of the differences lie within the limits of agreement. The simplicity of sperm counting with a photometer greatly enhances the usefulness of sperm count determination in onfarm AI laboratories.

International audience; We have studied the mechanochemical synthesis of NaNbO3, prepared from a powder mixture of Na2CO3 and Nb2O5. The formation of NaNbO3 during milling was followed using thermal analysis and X-ray diffraction. According to the thermogravimetric analysis, after 20 and 40 h of milling there was still some residual carbonate, while the X-ray diffraction shows NaNbO3 as the major crystalline phase present in the mixture. Based on the quantitative XRD phase analysis, the residual reactants were amorphous and as such undetectable with the X-ray diffraction. Furthermore, an X-ray line-broadening analysis was used to determine the NaNbO3 crystallite size and the microstrain. A decrease in the NaNbO3 crystallite size coupled with an increase in the amount of microstrains was found from 10 to 40 h of mechanochemical treatment. Finally, the TEM analysis confirmed the NaNbO3 crystallite size determined by the X-ray line-broadening analysis.

Four ternary compositions in the Ce2O3 rich part of the Ce2O3-SiO2-ZrO2 System were investigated. The corresponding mixtures of CeO2, SiO2 and ZrO2 were fired at 1400 degrees C in an Ar + 7% H-2 atmosphere until the phase equilibria were attained. The samples were characterized by XRD, SEM and EDS analysis. The thermal effects and the mass changes of the fired compositions were monitored by DTA/TG analyses. The oxyapatite phase, Ce-4.67(SiO4)(3)O, and the fee phases identified as the solid solutions (CeZr)O2-y, (CezZr1-z)O2-x, and Ce2Zr2O7+2 delta were observed in this part of the Ce2O3-SiO2-ZrO2 system. The DTA/TGA analyses indicated the presence of the Ce+4 ions in the fired compositions, while the lowest melting temperature was noticed at 1627 degrees C. (c) 2006 Elsevier Ltd. All rights reserved. 9th Conference and Exhibition of the European-Ceramic-Society, Jun 19-23, 2005, Portoroz, Slovenia

Our aim was to examine the diagnostic potential of matrix metalloproteinases MMP-2 and MMP-9 for identifying osteoarthritis in the horse. Horses were divided into two groups - a positive group consisting of 28 horses with cartilage damage in the distal interphalangeal joint and a negative group of 17 control horses. Clinical examination of the horses included evaluation of lameness, flexion test, diagnostic nerve blocks, X-ray and arthroscopy. MMP-2 and MMP-9 were detected in synovial fluid using gelatin zymography. Monomers of MMP-2 and MMP-9 appeared not to be specific for osteoarthritis since they also occurred in control samples. In contrast, detection of active forms of MMPs was found to be more effective than radiological examination in identifying horses with osteoarthritis, on the grounds of higher sensitivity. Active forms of MMP-2 and MMP-9 were observed with 88.24% and 82.35% specificity respectively, indicating the high accuracy in correctly identifying horses without osteoarthritis. Thus, as an addition to clinical examination, detection of MMPs could improve the diagnosis of osteoarthritis. Detection of active forms of MMP-2 and MMP-9 was evaluated as an additional diagnostic tool in diagnosing osteoarthritis, especially in the case of a negative X-ray result. The proportions of animals with confirmed osteoarthritis, which tested positive, were found to be 81.82% and 76.92%, respectively. The results of this study confirm that active forms of MMP occur in synovial fluid of osteoarthritic joints more frequently than in synovial fluid from normal joints of the horse. Detection of active forms of MMP-2 and MMP-9 is shown to have an important diagnostic potential.

The phase composition, microstructure and electrical properties of thick-film structures based on 0.65Pb(Mg 1/3 Nb 2/3 )O 3 –0.35PbTiO 3 (PMN–PT) were studied. PMN–PT powder with 2 mol% of excess PbO was prepared by high-energy milling from the constituent oxides. A high yield of perovskite PMN–PT with nano-sized particles was obtained after the synthesis. A paste was prepared from the obtained powder, screen printed on platinised alumina substrates and sintered at 850, 900 and 950 °C. Single-phase PMN–PT thick-film structures without any pyrochlore phase were obtained after the sintering. The dense PMN–PT layers had good dielectric, piezoelectric and ferroelectric properties. The relative dielectric permittivity of 4100 and the peak value of 41,000 for the film sintered at 950 °C compare well with bulk ceramics sintered at much higher temperatures. The d 33 value of the film was 170 pC/N. The obtained values for the dielectric properties demonstrate the good chemical homogeneity of material synthesized by high-energy milling.

Lanthanum lead zirconate titanate with 5 at.% of La (5/65/35 PLZT) hot-pressed ceramics have been studied in order to explore its dielectric properties below Burns temperature. Previous measurements of 6.5/65/35 hot-pressed PLZT ceramics revealed relaxor-ferroelectric behavior, i.e. coexisting ferroelectric and relaxor dielectric response. Similar relaxor behavior, though not so pronounced, was also expected at lower concentrations of La in 5/65/35 hot-pressed PLZT ceramics. We explored the possible duality of ferroelectric and glassy relaxor behavior in 5/65/35 hot-pressed PLZT ceramics with measurements of the complex linear dielectric susceptibility as a function of temperature and bias electric field. These experiments revealed no indications of prominent relaxor behavior. Results revealed solely a smeared relaxor to ferroelectric transition. Moreover, polarization hysteresis measurements below this transition confirmed existence of the ferroelectric phase in zero bias electric field in 5/65/35 hot-pressed PLZT ceramics without relaxor features like freezing process and frequency dependence.

The aim of this study was to investigate the production andreproduction ability of Slovenian brown-breed dairy cows according totheir exposure to negative energy balance (NEB). Body condition score(BCS), concentrations of metabolites such as non esterified fatty acids(NEFA), beta hydroxy butyrate (BHB), cholesterol and urea weremeasured on day 14 postpartum and progesterone profile wasdetermined for each animal. The postpartum period was closelymonitored from day 14 to conception by ultrasound examination in 10day intervals. Reproductive parameters were followed up, also. CowsweredividedintwogroupsaccordingtoNEFAandBHBconcentrationswith a threshold of 0.5 and 1.4 mmol/L, respectively. Cows withelevated NEFA and BHB levels (Group 2) in comparison to Group 1expressed a higher decrease in BCS 30 days postpartum (0.64 vs 0.33point; P

We have studied the mechanism of the mechanochemical interaction between Na 2 CO 3 and Nb 2 O 5 in the initial stage of milling, before the final crystalline oxide product, i.e., NaNbO 3 , is formed. In order to do this, the milling parameters were chosen to give a relatively low ball-impact energy. In addition, one of the reactants, i.e., Na 2 CO 3 , was milled also individually so that the mechanochemical effect on the separately milled compound could be determined. X-ray diffraction analysis, thermal analysis and infrared spectroscopy were used in order to characterize the samples after different milling times. The mechanochemical treatment of the Na 2 CO 3 –Nb 2 O 5 mixture results in the formation of a carbonato complex, which represents an intermediate stage in the mechanochemical synthesis of NaNbO 3 .

The dielectric behaviour of tetragonal PLZT x/40/60 ceramics doped with lanthanum (x = 5, 12 and 15%) has been investigated at 100–1014 Hz. Dielectric, THz and infrared spectra were measured from 500 to 20 K. For x ≥ 12 relaxor ferroelectric behaviour was observed. All three samples showed an additional relaxational mode below phonons. Analysis of the phonon modes for ferroelectric PLZT 5/40/60 is presented together with the complete dielectric behaviour.

Aim: To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality. Methods: The accuracy of the spectrophotometric application of the resazurin reduction assay was assessed using receiver operating characteristic (ROC) analysis. Results: Areas under ROC curves (AUC) for motile sperm concentration and sperm index (SI) (sperm concentration multiplied by the square root of percentage sperm motility multiplied by the percentage normal sperm morphology) were 0.922. The best discrimination between poor and good semen samples according to the SI was achieved at a cut-off point of A610 = 0.209, where high sensitivity (94.1%) and specificity (91.7%) were calculated. The assay was less accurate when motile sperm concentration was used as the criterion value, yielding sensitivity of 88.2% and specificity of 87.5%, respectively. Likelihood ratios (LR) indicate that absorbances lower than 0.209 were at least 11.3 times as likely to be found in good semen samples than those in poor according to the SI, whereas in the case of motile sperm concentration, the LR was calculated to be 7.06. Conclusion: These results show that the resazurin reduction assay combined with spectrophotometry is an accurate method of assessing the quality of boar semen. (Asian J Androl 2006 May; 8: 343–348)

Molybdenum disulphide (MoS2) might be a useful addition in the production of composite self-lubricating high-speed steel parts, which are used in different anti-wear applications. MoS2 might also has a favourable influence on the synthesis of sintered high-speed steels (HSSs) improving the compressibility of the metal powder mixture during its cold compaction, as well as acting as a sinterability enhancer of powder compacts during their sintering. In view of this, the compressibility and the sinterability of M3/2 and M35 types of HSS powder mixtures with MoS2 additions were investigated. In this article, the influence of MoS2 additions on the densification during cold compaction and vacuum sintering of selected HSSs is presented. It has been established that the MoS2 promotes a consolidation of HSS powders during automatic die compaction, as well as final densification during sintering. Sintering of HSS-MoS2 powder mixtures proceeds by the combination of a reactive and supersolidus liquid-phase sintering process. The added MoS2 reacts with the steel matrix, enhancing densification. Fine dispersion of complex sulfides (Cr, V, Fe)S is formed, which improves the machinability and tribological properties of sintered steel.

Ferroelectric strontium bismuth tantalate (SBT) thin films were deposited by thermal metalorganic chemical vapour deposition (MOCVD) onto a complex layered Pt/IrO 2 /Ir/Ti(Al)N substrate. A study of ultra-violet (UV)-assisted rapid thermal processing (RTP) annealing strategies of the SBT thin films was performed. The influence of UV irradiation temperature and annealing atmosphere on the crystallinity of the deposited films was evaluated using both microstructural and electrical analysis techniques. A UV-RTP strategy in an oxygen atmosphere above 400 °C, followed by a furnace treatment at 700 °C, provided an optimum remnant polarization figure of merit.

We have evaluated the use of a milling map in the mechanochemical synthesis of ceramic oxides. In order to do this we constructed a milling map for NaNbO3, mechanochemically synthesized from a powder mixture of Na2CO3 and Nb2O5. Based on the milling map, we determined the critical or minimum cumulative kinetic energy for the formation of NaNbO3. In addition, we made a comparison between several oxide systems by constructing the milling map on the basis of the experimental data found in the literature. It is shown that a milling map is essential for a comparison of the results of mechanochemical synthesis when different planetary mills and milling conditions are used.

The kinetics of the nanoscale structures under application of bipolar and unipolar ac field was investigated by recording of the switching charge in wide temperature and field range in hot-pressed relaxor PLZT ceramics. Original analysis of the switching charge data was based on the consideration of the field induced transformation as an evolution of the nanoscale domain structure with nanoscale nonpolar inclusions. We have shown that the inhomogeneous depolarization field produced by the bound charges existing at the interphase boundaries play the key role in spontaneous backswitching effects.

The switching under application of bipolar ac field is studied by recording of the hysteresis loops in wide temperature and field range in PLZT x/65/35 ceramics. The qualitative difference of the shape of hysteresis loops above and below the freezing temperature is attributed to backswitching in relaxor phase due to the depolarization field produced by the bound charges located at the interphase boundaries. The application of the quasistatic approach to analysis of the experimental data allows us to obtain parameters of the distribution function of local coercive fields from the field dependence of the switching charge derivative on field.

FrangeI R., T. Gider, M. Kosec: Frequency of Boar Ejaculate Collection: its Influence on Semen Quality, Pregnancy Rate and Litter Size. Acta Vet. Brno 2005, 74: 265-273. The aim of this study was to determine the best collection frequency for boar ejaculate, based on semen quality, pregnancy rate and litter size. Over a period of 7 months, 480 ejaculates were obtained, at successive collection frequencies of one, two, three and seven times per week, from 12 mature boars of line 54. For each ejaculate, the volume, progressive motility, spermatozoa concentration, sperm morphology and total number of spermatozoa were determined. Two commercial semen extenders, Beltsville Thawing Solution and Merck, were used for semen dilution and preservation. Smaller ejaculate volumes (P < 0.05), lower sperm concentrations (P < 0.05), and lower total sperm counts per ejaculate (P < 0.05) were obtained at collection frequencies of 7 and 3 than at 2 and 1 times per week. Significantly lower progressive sperm motilities at 7 than at 3, 2 and 1 times per week were observed. 1586 sows were inseminated with semen obtained at the four collection frequencies. The conception in sows was highest when inseminated with semen collected once per week and was significantly (P < 0.05) lower when collected 7 times per week than at the other three collection frequencies. The number of delivered piglets was also highest in sows inseminated with semen collected once per week and significantly(P < 0.05) higher than at collection frequencies of 2 and 3 per week. No significant differences in the semen quality parameters measured or in pregnancy rate were found when using either of the two commercial preservation extenders. These results indicate that the sperm quality decreases with increasing collection frequency and is most pronounced at the collection frequency 7 × per week. Taking into account the fertility rate and litter size, together with the number of semen doses obtained per week, the most suitable ejaculate collection frequency in mature boars of line 54 is two or three times per week.

Endoscopyc examinations were performed on 37 mares of different breeds. All examined mares had reproductive problems. During the examination, the following pathological changes were found: inflammation of endometrium in 19 cases (64.9%), uterus adhesions in 4 cases (10.8%), exudate in uterus lumen in 13 cases (32.4%), thin fibrin exudate in 8 cases (21.6%) and lymphatic cysts in 12 cases (32.4%). In one case adhesions in the cervical wall were found, and in one case there was hair encapsulated in the cervical mucus as a consequence of fetotomy. These changes were found in 2.7% of cases.

Dielectric dynamics in PLZT-P(VDF/TrFE) ceramics-copolymer composite has been studied by measurements of the temperature and frequency-dependent linear and third-order nonlinear dielectric constants. A paraelectric-to-ferroelectric phase transition in the crystalline region and a dielectric relaxation, which is a dynamic manifestation of the glassy-to-rubbery state transition in the amorphous phase of the system, were detected. The nature of the paraelectric-to-ferroelectric phase transition has been studied in detail by high-resolution nonlinear dielectric and calorimetric measurements. Results are compared to data obtained in P(VDF/TrFE) copolymer.

Dielectric response of two types of nominally pure hot-pressed PbZrO3 ceramics (PZ1 and PZ2) of similar density (97–98%) was studied in the 1 MHz–1 GHz and far infrared frequency ranges in a wide temperature interval. While the far infrared spectra of both ceramics did not significantly differ from that of the crystal and the permittivity of PZ1 appeared to be comparable to that of the crystal, the permittivity of PZ2 was much lower. This reduction was particularly drastic (of about four times) on approaching the antiferroelectric phase transition from the paraelectric phase. We succeeded to explain this effect using a brick-wall model assuming nano-cracks development along some of the grain boundaries in PZ2 in agreement with SEM observations and unusual mechanic fragility of this ceramics. Our estimates show that even small volume fraction (

Young boars were treated with propiothiouracil to induce hypothyroidism to examine its effects on postnatal testicular development. Treatments with 0.1% 4-propyl-2-thiouracil (PTU) in drinking water started after weaning, at 3 weeks of age and all boars were severely hypothyroid at 6 weeks of age as determined by measuring T3 and T4 in blood plasma. Boars were castrated at different ages up to 20 weeks and their testes used for histological and immunohistochemical analyses. Although small but significant reduction in testis weight was observed from 8 to 12 weeks of age, this was not accompanied by significant difference in testicular volume. By 20 weeks of age, at the beginning of puberty, the differences in testis weights between control and treated groups of boars disappeared suggesting there is no lasting effect of hypothyroidism on postnatal development of boar testis. Immunohistochemical staining was used to determine the presence of molecular markers in both Sertoli and Leydig cells. Again, there were no differences between testes from control and treated boars in the pattern or intensity of immunostaining using antibodies against 3beta-hydroxysteroid dehydrogenase, antimullerian hormone or proliferating cell nuclear antigen (PCNA). Immunostaining with antibodies against PCNA showed interesting results as it was observed that Sertoli cells still express this marker of proliferating cells at 14 weeks of age, later than previously suggested cessation of Sertoli cell proliferation. This study suggests that hypothyroidism in boars does not have similar effects on postnatal testis development as reported in some other species.