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71.
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Untrained Octopus vulgaris (observers) were allowed to watch conditioned Octopus(demonstrators) perform the task of selecting one of two objects that were presented simultaneously and differed only in color. After being placed in isolation, the observers, in a similar test, consistently selected the same object as did the demonstrators. This learning by observation occurred irrespective of the object chosen by the demonstrators as the positive choice and was more rapid than the learning that occurred during the conditioning of animals. The task was performed correctly without significant errors and further conditioning for 5 days. These results show that observational learning can occur in invertebrates. 相似文献
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Aldhous P 《Science (New York, N.Y.)》1992,257(5076):1471
76.
The slip rate of a fault segment is related to the length of the fault zone of which it is part. In turn, the slip rate of a fault zone is related to its connectivity with adjoining or contiguous fault zones. The observed variation in slip rate on fault segments in the San Francisco Bay area in California is consistent with connectivity between the Hayward, Calaveras, and San Andreas fault zones. Slip rates on the southern Hayward fault taper northward from a maximum of more than 10 millimeters per year and are sensitive to the active length of the Maacama fault. 相似文献
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Pollard JC Littlejohn RP Johnstone P Laas FJ Corson ID Suttie JM 《New Zealand veterinary journal》1992,40(2):56-61
Heart rate and behaviour during and following velvet antler removal were monitored in yearling red deer stags to determine the extent to which this procedure was perceived by the deer to be aversive. Nine stags normally kept at pasture were habituated over 5 weeks to the following daily handling procedure. Each deer was fitted with a harness containing a heart rate monitor. It was then allowed to run through a fixed course in a deer yard, restrained for 40 s in a mechanical deer crush, and then confined for 3.5 h with the remainder of the group of stags in an indoor pen containing food and water. In Week 6, the deer were subjected to either restraint for 6 minutes (the control treatment) or removal of one velvet antler under local anaesthesia. Each velvet antler was removed on separate occasions, either on Days 1 and 2 (five deer) or Days 3 and 4 (four deer). The control treatment was applied to all deer when velvet antler was not being removed, and on Day 5. Heart rate and behaviour (time taken to enter the treatment area, and number of struggles made during restraint) were measured before and during treatment, and post-treatment activities were recorded at 0, 1 and 3 h (indoors), and at 6 and 9 h (at pasture). Heart rate was higher during the second velvet antler removal treatment than during the first, but lower during the second control treatment than the first (P<0.05). During velvet antler removal, stags struggled more, and after the treatment flicked their ears, shook their heads, and groomed themselves more than control stags (P<0.05). Stags whose velvet antler had been removed spent less time eating than control stags, and spent progressively more time sitting during the 3.5 h of confinement (P<0.05). However, during the paddock observation at 9 h post-treatment, stags which had had their velvet antler removed grazed more than control stags (P<0.05). The increase in heart rate over the two velvet antler removal treatments and the greater amount of struggling during velvet antler removal indicated that it was more aversive than the control treatment. Post-treatment differences in behaviour may have been due to pain following velvet antler removal. 相似文献
80.
Walter GL McGraw P Tvedten HW 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1992,21(1):23-27
An enzymatic, kinetic method for determining serum lipase activity was evaluated and compared to a standard manual method for use in dogs. The kinetic method was a commercial kit adapted for use on a tandem access clinical chemistry analyzer and utilized a series of coupled enzymatic reactions based on the hydrolysis of 1,2-diglyceride by lipase. The manual method was the Cherry-Crandall technique based on the titration of base against the acid formed by hydrolysis of an olive oil substrate by lipase. The correlation between the two methods was very good (r = 0.94). The reference range for 56 clinically healthy dogs assayed by the kinetic method was 90 to 527 U/L. Diseases associated with a greater than twofold elevation in serum lipase activity as determined by the kinetic method included pancreatitis, gastritis with liver disease, and oliguric renal failure with metabolic acidosis. In some cases, pancreatitis was seen with other clinical problems, such as gastroenteritis, diabetic ketoacidosis, duodenal mass, disseminated intravascular coagulation, and septic peritonitis. Diseases associated with serum lipase activity within the reference range or elevated less than twofold included gastritis, gastric ulcer, cholestasis, phenobarbital-induced hepatopathy, colitis, copper hepatopathy, abdominal hematoma, apocrine gland adenocarcinoma, and thrombocytopenia with pneumonia. 相似文献