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41 heifers of 260-440 kg body weight used in an experiment were polyovulated with PGF2 alpha and PMSG (1000 IU). Animals were slaughtered during luteal phase of ovarian cycle (day 12-15). Shortly before slaughter ovarian structures were defined by rectal palpation und ultrasonographical examination. Post mortem ovaries were collected to compare their structures with previously performed in vivo diagnosis. More follicular structures were detected sonographically (109%) than could be found by morphologic examination (100%). Concerning corpora lutea a right diagnosis was made by palpation in 94% of cases, whereas the rate was only 85% for ultrasonographical examination. Main reasons for false diagnoses of ultrasonographical examination are as follows: multiple ovarian structures, corpora lutea with holes inside, atypical shape of ovaries, atypical ultrasonographical pictures and irregular shape of follicles.  相似文献   
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We discuss how the standard Cost-Benefit Analysis should be modified in order to take risk (and uncertainty) into account. We propose different approaches used in finance (Value at Risk, Conditional Value at Risk, Downside Risk Measures, and Efficiency Ratio) as useful tools to model the impact of risk in project evaluation. After introducing the concepts, we show how they could be used in CBA and provide some simple examples to illustrate how such concepts can be applied to evaluate the desirability of a new project infrastructure.  相似文献   
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Owing to its well-known high complexing power toward Al3+ ion, fluoride ion is able to increase the solubility of alumina in alkali chloride melts. To determine the extent of this effect, the formation of aluminium(III) fluoro-complexes was studied potentiometrically in LiCl-KCl eutectic at 470°. But the sodium fluoride addition appeared to produce not only the complexation effect but also a mineralization effect on alumina. So, the thermodynamical stability of alumina formed in this melt by precipitation from aluminium chloride with carbonate ion (oxide anion donor) depends on the fluoride ion concentration. These two effects explain the solubility variation of alumina in the LiCl-KCl eutectic + NaF mixtures. A pF? - pO2? diagram, which represents the stability area of the various aluminium (III) species is established, and leads to some conclusions concerning the electrowinning of aluminium from molten chloride melts.The cumulative formation constants of the aluminium(lII) fluoro-complexes (AlF3?ii) have been obtained, whose values are the following: 2.5 ± 0.4, 4.7 ± 0.6, 5.7 ± 0.5, 7.5 ± 0.4, 8.0 ± 0.5, 9.0 ± 0.6, respectively for i = 1, 2, 3, 4, 5 and 6. It has been shown that oxyfluoride species such as AlOF1?ji does not exist. The solubility products of gamma and alpha-alumina have been determined and are equal to 10?42.9 and 10?44.0 respectively (all the constants are given in the molality scale). They differ widely from the solubility product of the alumina obtained in the absence of fluoride ion, ie 10?27.4.  相似文献   
5.
The stability of indium chloride and oxide as well as the electrochemical behaviour of indium ions have been studied in the equimolar CaCl2–NaCl melt at 550 C by X-ray diffraction (XRD) and different electrochemical techniques, using molybdenum and tungsten wires as working electrodes. Voltammetric and chronopotentiometric studies showed signals attributed to the presence of three oxidation states of indium, i.e. 0, i and iii. The standard potential of the redox couples, as well as the solubility products of indium oxides have been determined, showing that In(iii) ions are completely reduced to monovalent indium by the indium metal according to the reaction: In () + 2 In 3 In () and that In2O is a strong oxide donor according to the reaction: In2O(s) 2 In() + O2- These results have allowed the construction of E-pO2– equilibrium diagrams summarising the properties of In–O compounds. The electrodeposition of indium was uncomplicated at Mo and W electrodes. Very good adherence of liquid indium to the electrode materials was observed, with the formation of Na–In alloys at highly reducing potentials, and there was no evidence of indium dissolution into the melt. Moreover, the voltammograms corresponding to the electrochemical In(iii)/In(i) exchange were well defined. The two electrochemical steps were found to be quasi-reversible, and the values of the kinetic parameters, ko and , for both reactions, as well as the diffusion coefficients, DIn(III) and DIn(I) were calculated.  相似文献   
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The biochemical, metabolic and contractile characteristics of semitendinosus (ST) and longissimus thoracicus (LT) muscles were studied in 147 male Limousin cattle. The animals, which were slaughtered at 16 months, were the offspring of 15 different sires. Weight gain and carcass tissue composition (proportion of muscle and adipose tissue) were also measured. The biochemical characteristics of the two muscles studied had coefficients of variation between 13 and 30% markedly higher than for proximate characteristics of the carcass, in which coefficients were all lower than 18%. There were significant differences between the two muscles: ST had a higher protein/DNA ratio and greater lactate dehydrogenase (LDH) activity than LT, also a lower isocitrate dehydrogenase (ICDH) activity and lower slow myosin heavy chain (MHCI) content. The percentage of MHC 1 was positively correlated with ICDH activity and negatively with LDH activity and protein/DNA ratio. These muscle characteristics were also correlated with weight gain: animals with greater weight gain had a higher protein/DNA ratio and lower oxidative activity, with differences in the level of significance of the correlations according to muscles. Selection of animals on the basis of muscle growth may therefore be a means of improving the quality of meat.  相似文献   
8.
The ability to recognize emotion is one of the hallmarks of emotional intelligence, an aspect of human intelligence that has been argued to be even more important than mathematical and verbal intelligences. This paper proposes that machine intelligence needs to include emotional intelligence and demonstrates results toward this goal: developing a machine's ability to recognize the human affective state given four physiological signals. We describe difficult issues unique to obtaining reliable affective data and collect a large set of data from a subject trying to elicit and experience each of eight emotional states, daily, over multiple weeks. This paper presents and compares multiple algorithms for feature-based recognition of emotional state from this data. We analyze four physiological signals that exhibit problematic day-to-day variations: The features of different emotions on the same day tend to cluster more tightly than do the features of the same emotion on different days. To handle the daily variations, we propose new features and algorithms and compare their performance. We find that the technique of seeding a Fisher Projection with the results of sequential floating forward search improves the performance of the Fisher Projection and provides the highest recognition rates reported to date for classification of affect from physiology: 81 percent recognition accuracy on eight classes of emotion, including neutral  相似文献   
9.
Metallurgical and Materials Transactions A - We have examined spheroidization and coarsening of cementite in an initially pearlitic 2C-4Cr ultrahigh carbon steel containing a cementite network....  相似文献   
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