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Tang Helen H. Y.; McNally Gavan P.; Richardson Rick 《Canadian Metallurgical Quarterly》2007,121(6):1421
The authors studied the role of gamma-aminobutyric acid (GABA) in 2 types of forgetting of fear in the developing rat. One type of forgetting studied was that observed after an intermediate retention interval (the "Kamin effect"); the other type studied was that observed after a longer interval (infantile amnesia). Rats were given pairings of an auditory conditioned stimulus with shock, and learned fear was assessed by freezing. Forgetting at an intermediate retention interval (1 hr) was not alleviated by the GABAA receptor partial inverse agonist FG7142 (0, 1, 5, or 10 mg/kg), whereas forgetting at a longer retention interval (48 hr) was alleviated. These results suggest that in the developing rat, forgetting observed at different retention intervals is mediated by different physiological mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Charles George Clare Rowland France Gerard Heiko Balzter 《Remote sensing of environment》2006,104(3):346-359
The boreal forest contains almost half the total carbon pool of world forest ecosystems, and so has a very significant role in global biogeochemical cycles. The flux of greenhouse gases in and out of these forests is influenced strongly by disturbances such as diseases, logging and predominantly fire. It is important to quantify these disturbances to enable the modelling of major greenhouse gases. However, because of the remoteness and vastness of the boreal forest, little data is available on the type, extent, frequency and severity of these disturbances in Siberia. For burnt areas, two of the more responsive wavelengths are the short wave infra-red (SWIR) and the near infra-red (NIR). These produce a vegetation index, the normalised difference SWIR (NDSWIR) capable of detecting retrospective disturbances. Here we combine the NDSWIR from MODIS imagery acquired in the summer of 2003 with thermal anomaly data from 1992 to 2003 to detect and date areas which burnt at some point between 1992 and 2003. The semi-automated method is called SWIR and Thermal ANomalies for Detecting Disturbances (STANDD) and is complemented by an Normalised Difference Vegetation Index (NDVI) differencing method using MODIS 2002 and 2003 imagery to ensure reliable detection of area burnt in the year of image acquisition (i.e. 2003). The area of this study covers approximately 3 million km2 stretching from Lake Baikal in the south to the Laptev Sea in the north, above the Arctic Circle. Landsat ETM+ images were used to validate the shape and areal extent of the burnt areas resulting in an 81% overall accuracy with a kappa coefficient of agreement of 0.63. 相似文献
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OBJECTIVE: To examine the association between sexual abuse in childhood and adult depression in women. DESIGN: Two stage, case detection and case identification design, using the 30-item general health questionnaire and the Beck depression inventory for screening and the affective items relating to current functioning on the schizophrenia and affective disorders schedule to identify depressed cases. Details of sexual abuse in childhood were elicited retrospectively by semistructured interview, and social problems by the social problems questionnaire. SETTING: Three general practices, in middle class suburban, deprived inner city, and rural areas. SUBJECTS: 1189 women were screened and 237 subsequently interviewed; 132 were depressed. RESULTS: 49 (37%) of the depressed interviews and 24 (23%) of the non-depressed interviews reported experience of sexual abuse when they were aged under 16 years. A positive association existed between the more severe abuse and depression--all those who had experienced penetration were depressed as adults. A relation was also found between sexual abuse in childhood and sexual problems, housing problems, and problems with their children at school. CONCLUSION: A positive association between child sexual abuse and depression was confirmed, but this was confined to more severe abuse (penetration or attempted penetration). 相似文献
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Helen N. Asemota Max A. Wellington Adewale A. Odutuga Mohammed H. Ahmad 《Journal of the science of food and agriculture》1992,60(3):309-312
The effect of short-term storage on the protein, phosphorus and phenolic content as well as peroxidase and o-diphenolase activities of cut, harvested Jamaican yam (Dioscorea sp) tubers (D rotundata. D alata and D cayenensis) was studied. There was an initial increase in the total phenolic content up to the third week of storage followed by a gradual decrease to the sixth week. Phenolic content was found to be highest in D cayenensis followed by D rotundata and D alata. The activities of peroxidase (EC 1. 11. 1. 7) and o-diphenolase (EC 1. 10.3.1) increased steadily up to the third week of storage and thereafter decreased to the fifth week. The intensity and rapidity of browning in tubers when cut, correlated very closely with the tuber o-diphenolase and phenolic content levels while the onset of rotting correlated with the peroxidase activity levels in the species studied. 相似文献
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Staub Adrian; Rayner Keith; Pollatsek Alexander; Hy?n? Jukka; Majewski Helen 《Canadian Metallurgical Quarterly》2007,33(6):1162
Readers' eye movements were monitored as they read sentences containing noun-noun compounds that varied in frequency (e.g., elevator mechanic, mountain lion). The left constituent of the compound was either plausible or implausible as a head noun at the point at which it appeared, whereas the compound as a whole was always plausible. When the head noun analysis of the left constituent was implausible, reading times on this word were inflated, beginning with the first fixation. This finding is consistent with previous demonstrations of very rapid effects of plausibility on eye movements. Compound frequency did not modulate the plausibility effect, and all disruption was resolved by the time readers' eyes moved to the next word. These findings suggest (contra Kennison, 2005) that the parser initially analyzes a singular noun as a head instead of a modifier. In addition, the findings confirm that the very rapid effect of plausibility on eye movements is not due to strategic factors, because in the present experiment, unlike in previous demonstrations, this effect appeared in sentences that were globally plausible. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献