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Notes: This combined light and scanning electron microscopic (SEM) analyses are the first investigation of the fine morphology of the fetal membranes of the placenta in the Asian elephant. We used two term placentas with gestation periods of 634 days (Zoological Garden Leipzig) and 657 days (Zoo Hagenbeck) and selected unequal sites as specimens, particularly - free membrane of the allantois, - lateral edge of the placenta band, the ‘haemophagous zone’, - allantochorion near the placental band, and allantochorion on the end of the chorioallantoic sac. Microscopically the free membrane of the allantois shows a simple, cuboidal epithelium with apical domains of microplicae and microvilli (fig. 1, inset). In the SEM analyses we documented a cobblestone-like architecture of the epithelial cells with various cell sizes, small, middle and giant (fig. 1.). Furthermore, we found pear-shaped cells with long pedicle, attached to the basement membrane and cell openings, presumably due to cell desquamation (fig. 2.). The haemophagous zone was characterized with a lamellate system between the long finger-like chorionic villi and the maternal blood lacunae. The simple, squamous and columnar trophoblast cells are here bathed in the maternal blood. In some chorionic villi brown-yellow material is deposited in the fetal connective tissue. A special result was the presence of strip-like microplicae in the middle of chorionic villi. The allantochorion near the placental band sometimes indicated simple and ramified chorionic villi with smooth, gyrus-like trophoblast cells and foamy cytoplasm. The attached allantois possesses a simple, columnar epithelium with microvilli. Furthermore, we observed villi-like projections rising up to the allantoic cavity. The white ‘pustules’ on the outer surface of the end of the chorioallantoic sac consist of stratified squamous epithelia. Numerous mitoses were documentedin the basal domain of the pustules. A surprisingly result was the presence of intra-epithelial capillaries. They invade the trophoblast cells to presume a nutrient exchange also outside of the placental band with its important functional metabolism. This study revealed unknown and interesting features of the epithelial layer of different locations in the placenta of the Asian elephant. Perhaps, with a detailed knowledge of the morphology of the epithelium we could convey a better understanding of functional cohesions of elephant placentation. 〈displayedItem type="text" xml:id="fu1"〉1〈mediaResource alt="image" href="urn:x-wiley:03402096:AHE669_43_43:AHE_669_fu1"/〉[ The free membranes of the allantois of the term placenta of the Asian elephant (Elephas maximus) shows a cobblestone-like architecture of the simple cuboidal epithelial cells with various sizes. The surface morphology was determined through microplicae and microvilli. ] 〈displayedItem type="text" xml:id="fu2"〉2〈mediaResource alt="image" href="urn:x-wiley:03402096:AHE669_43_43:AHE_669_fu2"/〉 [ Numerous pear-shaped cells with long pedicle exist among the cuboidal epithelial cells, attached on the basement membrane. The cells possessed modifications of their surface, particularly microplicae. Some pear-shaped cells shows only the pedicle, perhaps that is a loss through preparation or its presumable due to cell desquamation. One erythrocyte is localized between these cells. ]

Notes: We investigated the embryotoxicity of ozone (O3), after gas exposure in ovo, to chick embryos of the Lohmann-Weiss strain. The main aim of the study is to reduce the microbiological content, particularly of Salmonella enteritides on the egg surface by the use of ozone in different concentrations and response times. The aim of our morphological study is to analyse the influence of gas exposure to the embryonal development of chick. Ozone has proved its worth as a disinfectant without the harmful adverse effects of formaldehyde. The chick embryo provides a useful and well-defined model for analysis of toxicity of chemicals, particularly with regard to an alternative disinfectant: ozone. Embryotoxicity of ozone in developing chick embryos was studied by examining different parameters: deformities and pathohistology of heart, liver, kidney and spleen, weight, length and survival of embryo. After oviposition the eggs were transferred to a chamber filled with ozon-oxygen-mixture in a defined concentration (1% - 5.22%). After achievement of the ozone concentration the eggs were incubated over various response times have 20, 30, 60 min or 17 h. After the incubator times of 18, 19 or 20 days we studied the development of the gas exposed embryos and unexposed controls. The organs were fixed in 4% formalin, embedded in paraffin, cut and stained with hematoxylin-eosin. High ozone concentration over 5% and high response time of 1 hour provided low graded survival rates of 3.3–13.3%. There was significantly increase of the survival rate after decline of ozone concentration and response time of 90–100%. We found also a remarkable decrease of weight and length in fewer surviving gas exposed embryos with high ozone concentration and response time (Fig. 1.), compared with the normal development of gas-exposed embryos with study of high survival rate (Fig. 2.). We calculated a 60% increase in the survival rate of embryos exposed to high ozone concentration without response time. In low ozone concentration (1.8%) with high response time of 17 hours the survival rate decreased to 10%. We found no signs of deformities and pathohistology of organs in our embryological examination. In conclusion, ozone has a dose-dependent effect. The response time constitutes an important factor in the survival and growth of chick embryos after exposure to ozone in ovo. 〈displayedItem type="text" xml:id="fu3"〉1〈mediaResource alt="image" href="urn:x-wiley:03402096:AHE669_44_44:AHE_669_fu3"/〉 [ High ozone concentration over 5% and high response time of 1 hour result in a low survival rate of 3,3% and the surviving embryo shows a decrease in body weight and length (right) in comparison to the biggest (left) and lowest (middle) unexposed embryo. ] 〈displayedItem type="text" xml:id="fu4"〉2〈mediaResource alt="image" href="urn:x-wiley:03402096:AHE669_44_44:AHE_669_fu4"/〉 [ Height comparison between the unexposed controls (both embryos on the left side) with gas exposed embryos (both embryos on the right side) in a study with low ozone concentration of 1% and low response time of 20 minutes. There are no differences in body weight and length between the unexposed and exposed embryos. ]

Notes: We report magnetoresistance in ferromagnet / superconductor / ferromagnet structuresmade of La0.7Ca0.3MnO3 and YBa2Cu3O7 in the current in plane (CIP) geometry when thetemperature is fixed along the superconducting transition and the magnetic field is swept in anhysteresis loop sequence. We describe experiments changing the geometry of current versus field.We find that the shape and height of the magnetoresistance peaks is not modified no matter thefield is directed parallel or perpendicular to the current. This excludes interpretations in terms ofspontaneous vortices or anisotropic magnetoresistance of the ferromagnetic layers and supportsthe view that the magnetoresistance phenomenon originates at the spin dependent transport ofquasiparticles transmitted from the ferromagnetic electrodes into the superconductor