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Wild bonnet macaques (Macaca radiata) have been shown to recognize models of leopards (Panthera pardus), based on their configuration and spotted yellow coat. This study examined whether bonnet macaques could recognize the spotted and dark melanic morph when partially concealed by vegetation. Seven troops were studied at two sites in southern India, the Mudumalai Wildlife Sanctuary and the Kalakad-Mundanthurai Tiger Reserve. The forequarters and hindquarters of the two leopard morphs were presented from behind thick vegetation to individuals at feeding stations 25 m away. Flight reaction times and frequency of flight were obtained from video for only those individuals who oriented towards the models prior to hearing alarm calls. Bonnet macaques exhibited faster reaction times and greater frequency of flight after looking at the spotted morph's forequarter than after looking at either its spotted hindquarter or the dark morph's forequarter. The hindquarter of the dark morph was ignored completely. Artificial neural network modeling examined the perceptual aspects of leopard face recognition and the role of spots as camouflage. When spots were integrated into the pattern recognition process via network training, these spots contributed to leopard face recognition. When networks were not trained with spots, spots did not act as camouflage by disrupting facial features. 相似文献
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This paper presents a novel approach for acetabular alignment during the implant of a prosthetic hip joint in a natural pelvis. The alignment instrument uses selective anatomic bony landmarks on the pelvis, which are accessible in surgery, to guide the placement of the acetabular component in the appropriate orientation. A closed form solution, involving both a forward and reverse analysis, is presented to relate the parameters of the device with the abduction and anteversion angles. Using mathematical models, this device should allow the surgeon to place the acetabular component with an orientation between 10.9 degrees and 19.1 degrees anteversion and 35.7 degrees and 44.3 degrees abduction with 95% confidence in a male/left specimen for the commonly accepted target of 15 degrees anteversion and 40 degrees abduction. This device is currently being used successfully by one of the authors in THR surgery. 相似文献
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BACKGROUND: Pheochromocytoma is a common tumor of the adrenal medulla, but its pigmented variant is rare. CASE REPORT: A 38-year-old woman presented with complaints of abdominal pain. Ultrasound revealed a right suprarenal mass. Fine needle aspiration (FNA) smears showed the characteristic cytomorphology of pheochromocytoma, with melanin pigment in the cytoplasm. Melanin was differentiated from lipofuschin and hemosiderin by various histochemical stains. Histopathologic findings and immunohistochemical stains confirmed the diagnosis. To our knowledge, this is the first reported case of pigmented pheochromocytoma diagnosed on FNA. CONCLUSION: FNA has proven to be a rapid and conclusive method of diagnosing pigmented pheochromocytoma, with no complications. 相似文献
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In non-irrigated agricultural fields in tropical zones, high temperature and water stress prevail during the main cropping season. Natural epizootics of Beauveria bassiana on lepidopteran pests occur during winter. Application of B. bassiana during hot months when pest populations are at their climax may prove an effective management strategy. Therefore, 29 isolates of B. bassiana were tested for their ability to germinate and grow in temperature and water availability conditions prevailing during the pest season in these fields. The effect of temperature cycles with 8 h duration of high temperature fluctuating with 16 h duration of lower temperature (similar to field conditions); low water availability; and a combination of these two stress conditions was studied. Germination and growth assays were done at fluctuating temperature cycles of 32, 35, 38, and 42+/-1 degrees C (8 h)/25+/-1 degrees C (16 h) and in media with water stress created by 10, 20, 30, and 40% polyethylene glycol (PEG 6000). Assays set at a continuous temperature of 25+/-1 degrees C with no PEG in the medium served as controls. Stress was assessed as percentage germination or as growth relative to control. Isolates showing 90% growth relative to the control at temperature cycles including high temperatures of 35 and 38+/-1 degrees C were identified. One isolate (ARSEF 2860) had a thermal threshold above 43 degrees C. At 25 degrees C, all but one isolate of B. bassiana showed >90% growth relative to the control in 10% PEG (-0.45 MPa). Some isolates were found with >90% growth relative to control in medium having 30% PEG with water availability (1.33 MPa), nearly equivalent to that in soils which induce permanent wilting point of plants. When isolates that showed >90% growth relative to the control at both stress conditions, were stressed simultaneously, a decrease in growth was observed. Growth was reduced by approximately 20% at 35+/-1 degrees C (8 h)/25+/-1 degrees C (16 h) and 10% PEG and was affected to a greater degree in combinations of harsher stress conditions. The isolate ARSEF 2860 with a thermal threshold of >43 degrees C showed approximately 80% relative growth at a combined stress of 38+/-1 degrees C (8 h)/25+/-1 degrees C (16 h) and 10% PEG. These findings will aid the selection of isolates for use in field trials in hot or dry agricultural climates. 相似文献
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Two new ascomycetes, Boerlagiomyces costaricensis (Pleosporales) and Scopinella musciformis (Sordariales sensu lato), from litter samples collected in rainforests of Costa Rica, are described and illustrated. Boerlagiomyces costaricensis has globose, ostiolate ascomata covered by numerous setae-like hairs; cylindrical, fissitunicate asci without apical structures; and large, fusiform, muriform, hyaline to pale brown ascospores. Scopinella musciformis is characterized by ostiolate ascomata with a few compact clusters of hypha-like hairs distributed on the peridial surface and a long neck; ovate to ellipsoidal unitunicate asci; and small quadrangular ascospores with diagonal germ slits. 相似文献
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Radioprotective effect of aqueous extract of Ocimum sanctum (40 mg/kg body weight, for 15 days) in mice exposed to high-doses (3.7 MBq) of oral 131iodine was investigated by studying the organ weights, lipid peroxidation and antioxidant defense enzymes in various target organs like liver, kidneys, salivary glands and stomach at 24 hr after exposure in adult Swiss mice. The mean weight of the salivary glands showed significant increase after 131iodine administration. 131iodine exposure significantly increased lipid peroxidation in kidneys and salivary glands in comparison to control animals. Pretreatment with O. sanctum in radioiodine exposed group showed significant reduction in lipid peroxidation in both kidneys and salivary glands. In liver, reduced glutathione (GSH) levels showed significant reduction after radioiodine exposure while pretreatment with O. sanctum exhibited less depletion in GSH level even after 131iodine exposure. However, no such changes were observed in stomach. The results indicate the possibility of using aqueous extract of O. sanctum for ameliorating 131Iodine induced damage to the salivary glands. 相似文献