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The understanding of the effect of physical activity (PA) on food intake is imperative for considering PA as an additional tool for prevention and treatment of many diseases. Prolonged strenuous PA performed on a regular basis causes an increase in overall energy turnover, and leads either to loss of body weight, or to an increased food intake. When leading to loss of body weight, PA may be used as a therapeutic adjunct in the treatment of obesity. When increasing food intake to compensate for increased energy expenditure and maintaining body weight, PA, by increasing intake of other constituents of food like minerals and vitamins, may contribute to micronutrient deficiency coverage. However, the type of activity, as well as body composition of the individuals engaging in sport, play an important role in food intake regulation and its changes with time. Some studies indicate that short-term exercise does not have the same effect on food intake as long-term exercise and that eventual increase in food intake due to increased PA does not follow the same pattern in obese as in lean individuals. To better understand the relationship between PA on food intake, current findings on this topic will be summarized in this paper.

A prospective study was performed to determine the relative availability of buspirone and amitriptyline after oral and transdermal routes of administration in 6 adult cats. For topical administration, drugs were compounded in a transdermal organogel containing pluronic and lecithin (PLO). Using a crossover design, each cat received a single dose of amitriptyline (5 mg) and buspirone (2.5 mg) by the transdermal and oral route of administration with at least a 2‐week washout interval between drug treatments. Blood samples were obtained at 0, 0.5, 1, 2, 4, 6, 8, 10, and 12 hours after drug administration for determination of plasma drug concentrations. Plasma concentrations of immunoreactive amitriptyline and buspirone were determined using commercial enzyme‐linked immunosorbent assay (ELISA) tests. Systemic absorption of amitriptyline and buspirone administered by the transdermal route was poor compared with the oral route of administration. Until supporting pharmacokinetic data are available, veterinarians and cat owners should not rely on the transdermal route of administration for treating cats with amitriptyline or buspirone. Key Words: Cat; Pharmacokinetics.

During research aimed at predicting the performance of the US Lunar Roving Vehicle on the moon, engineers at the US Army Engineer Waterways Experiment Station used a lunar soil simulant, the strength characteristics of which had to cover the possible strength range of the actual lunar soil. Three test methods for evaluating the strength characteristics of the simulant are described; these in turn are related to such basic properties as density and relative density. The friction angle for very low normal stresses, necessary to simulate lunar gravity conditions, was determined by a modified triaxial test technique. Cohesion was evaluated by trenching tests, which had been used successfully on the lunar surface during the Surveyor programme. Finally, tests were conducted with a cone penetrometer to establish relations between cone penetration resistance and relative density of the simulant. The results of the tests are described briefly. Dans les recherches effectés pour prévoir le fonctionnement du véhicule américain parcourant la surface de la lune (US Lunar Roving Vehicle—LRV), des ingénieurs de la ‘US Army Engineer Waterways Experiment Station’ ont utilisé un matériau simulant le sol lunaire dont les caractéristiques de résistance recouvrait la gamme possible des résistances du sol lunaire réel. On décrit trois méthodes d'essai pour évaluer les caractéristiques de résistance du matériau simulant; ces caract´eristiques, à leur tour, sont rapportées à des propriétés de base telles que la densité et la densité relative. On a utilisé une technique d'essai triaxial modifiée pour déterminer l'angle de frottement pour des contraintes normales très faibles, nécessaires pour simuler les conditions de pesanteur lunaire. La cohésion des matériaux fut évaluée par la méthode de creusement de tranchée, utilisée avec succès sur la surface lunaire pendant le programme ‘Surveyor’. Enfin on a proédé à des essais avec un pénétromètre à cône pour établir des rapports entre la résistance à la pénétration du cône et la densité relative du matériau simulant. Les résultats des essais sont décrits sommairement.

The interaction of copper with PECVD silicon oxynitride films was investigated by different analytical and electrical methods. Using AES-depth profiling and RBS measurements, no copper diffusion in films investigated was observed after applying a thermal stress of 450°C for 1 h. However, copper migration was detected after applying thermal and electrical stress simultaneously (BTS). C-Vand I-Vmeasurements before and after different BTS-conditions were performed on MIS-structures with coppe dots. The shift of the C-Vcurves resulting from copper migration decreases with an increasing N/O-ratio of SiOxNyfilms, demonstrating the better barrier properties of silicon nitride compared to silicon oxide. Additionally, the time to failure (TTF) was studied as a function of thermal and electrical stresses. Again, SiNx-samples achieved the highest TTF-values. The polarity dependence of the leakage current suggests a Cu ion drift transport mechanism.

Using67Zn Mössbauer absorption and emission spectroscopy, we have investigated the electronic structure at the A and B sites in the normal spinels (Zn)[Al2]O4, (Zn)[Fe2]O4 and (Zn)[Ga2]O4. Within each system, the center shift Sc at the A site is more positive. In all systems investigated, the electric field gradientVu at the B site is negative. The values for SC andVU scale with oxygen nearest-neighbour distance to Zn. In the Fe spinel, a transferred magnetic hyperfine field is observed at the Zn site below the antiferromagnetic ordering temperatureTN=10 K. For a more detailed discussion of the chemical bond, we have performed ab initio Hartree-Fock cluster calculations for the Al and Fe spinels. Our experimental and theoretical results show that all hyperfine parameters are essentially determined by covalency effects. Our data on the Ga spinel raise the question of a partially inverse structure.

57Fe and119Sn Mössbauer measurements have been carried out on powder samples of three differently substituted M-type barium hexaferrites. By57Fe Mössbauer measurements in an external magnetic field applied parallel to the γ-ray direction, we found a canted spin structure for all samples. Furthermore, we detected a strong preference of the Sn4+ ions for the 4f2 sites. From57Fe Mössbauer measurements aboveTN, we conclude that the substitution does not influence the 2b sites. The analysis of the magnetically split119Sn Mössbauer spectra at room temperature in the case of the Co-Sn and Zn-Sn substituted samples shows a strong difference between the two. The spectra were interpreted due to the different surroundings of the Sn4+ ions.

Abstract: First we studied the kinetics of the formation of Ba monoferrite by means of Mssbauer spectroscopy. The most important result is the considerable portion of hexaferrite existing after treatment of the starting materials between 800 and 900C, caused by a higher rate of diffusion of the Ba2+ ions in comparison to the Fe3+ ions. Second we report susceptibility measurements recorded in a temperature range of 4.3 K to 280 K and Mssbauer spectra at room temperature and at 4.2 K without and in the presence of an applied magnetic field of 6 T. The experimental data demonstrate that the magnetic behaviour of Ba monoferrite deviates to some extent from a simple antiferromagnetic.

Abstract: Conventional and resonance scintillation technique is used to study some Ga x Sn y Fe3−x−y O4 spinels. The better resolution of the Mssbauer spectroscopy with a resonance scintillation detector makes the observation of the fine structure in theP(H) distribution possible.P(H) is computed from the spectra by means of decomposition and stepped deconvolution methods. A qualitative interpretation of theP(H) is proposed on the basis of a polynomial model.

This Mössbauer study is concerned with the formation mechanism of hexaferrites (n=6) and of monoferrites (n=1) in the systems (1) BaCO3+nFe2O3, (2) SrCO3+nFe2O3and (3) 0.5BaCO3+0.5SrCO3+nFe2O3.

The individual steps of the preparation of M-type Ba-hexaferrite particles by the glass crystallization method were studied by means of Moessbauer spectroscopy. As starting materials, three different compositions of the system Fe2O3-BaO-B2O3 were used. The amorphous base materials were prepared by the twin roller quenching method. In these materials Fe3+ ions occupy both the tetrahedral and the octahedral sites in the glassy network. At high annealing temperatures not only the crystalline Ba-hexaferrite phase, but also an amount of approximately 16% of glassy phase can be found. The Fe3+ content at octahedral sites in the glassy phase rises from about 25% at an annealing temperature of 300°C to about 70 to 90% in annealing above 780°C.

The reason for the canted spin structure in several substituted hexaferrites has become more clear by 57Fe Mössbauer measurements on Cr3+substituted hexaferrites. In addition to previous investigations the site occupation of two samples was determined by means of neutron diffraction measurements at a temperature above the Curie point.