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The transition metal chalcogenide Ni(S,Se)2 is one of the few highly correlated, Mott-Hubbard systems without a strong first-order structural distortion that normally cuts off the critical behavior at the metal-insulator transition. The zero-temperature (T) transition was tuned with pressure, and significant deviations were found near the quantum critical point from the usual T1/2 behavior of the conductivity characteristic of electron-electron interactions in the presence of disorder. The transport data for pressure and temperature below 1 kelvin could be collapsed onto a universal scaling curve.  相似文献   
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The effects of conventional lime sulfide depilation and enzymatic depilation on the enamel layer of pickled lamb pelts were examined using atomic force and optical microscopy, immunohistological, and proteomic techniques. Microscopy showed that the surface structure of enzymatically depilated material was visibly less organized than conventionally processed material, implying that the enzymes used for depilation were responsible for this difference. Proteomic analyses identified an absence of collagen VI in the enamel of skins that had been processed with enzymes, in contrast to the skins that had been processed using conventional methods, which was confirmed using immunolocalization studies. It is therefore possible that the destruction of collagen VI during enzymatic depilation may cause the changes to the enamel structure observed during enzyme processing and in turn affect the quality of the finished product.  相似文献   
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SUMMARY Chronic fluoride toxicosis caused lameness, dental lesions and illthrift in an extensive beef cattle herd in northern Australia. Up to 15% of the herd was lame and the disease forced the culling of large numbers of cows. The source of fluoride was fertiliser-grade monoammonium and diammonlum phosphate fed as part of a mineral supplement. Large quantities of mineral supplement were provided to the cattle because lameness was attributed to phosphorus deficiency, which is endemic in the area. Most lameness developed in the late dry season in the post-lactation phase. Severe lameness was caused by fractured pedal bones.  相似文献   
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Inherited epidermal dysplasia (IED), formerly called baldy calf syndrome, is a lethal disease of calves of Holstein-Friesian ancestry. The disease causes progressive illthrift and skin, horn and hoof lesions, which can be confused with inherited zinc deficiency. The clinicopathological features and ancestry of 10 affected calves in Gippsland, Victoria are described.  相似文献   
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The success of embryo production in vitro depends upon the use of an efficient oocyte retrieval technique, and the best results have been obtained by laparoscopic aspiration. The aim of this study was to evaluate the effect of consecutive sessions of follicular aspiration on the quantity, quality and in vitro maturation competence of oocytes obtained from ewes subjected to hormonal stimulation. Six Santa Ines ewes underwent nine sessions of follicular aspiration by laparoscopy with a 7‐day interval between sessions, totalling 56 aspirations. After 24 h of culture, oocytes were stained and classified according to the stage of nuclear and cytoplasmic maturation. Oocyte retrieval rate was 61.4 ± 2%, resulting in a total of 249 oocytes. No significant variation was observed between sessions (p > 0.05). The average number of oocytes retrieved from each ewe was 6.4 ± 2 per session and 42 ± 4 in total. No significant difference was observed between the frequencies of the different stages of nuclear maturation: 32.72% mature, 40.74% immature and 26.54% degenerated/indeterminate oocytes; however, a significant difference was observed between the frequencies of the different stages of cytoplasmic maturation: 10.7% mature, 73.25% immature and 16.05% degenerated/indeterminate oocytes. No significant difference was observed in nuclear or cytoplasmic maturation between the weeks of procedure. We conclude that after nine consecutive sessions of follicular aspiration, the quantity and quality of retrieved oocytes remained unchanged as well as the levels of nuclear and cytoplasmic maturation obtained, demonstrating the viability of this technique for repetitive follicular aspirations on the same donor.  相似文献   
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Four cases are described of nervous disease associated with coccidiosis in young cattle. Prodromal nystagmus, ventromedial strabismus, sternal or lateral recumbency with contortions of the head and neck, near normal interictal periods and palpable proctitis were common findings. Differentiation from other nervous disorders in young cattle and the pathogenesis of the nervous signs associated with coccidiosis are discussed. It is suggested that the clinical picture is sufficiently distinctive to allow a diagnosis to be made on clinical grounds alone.  相似文献   
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