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91.
Sutherland Robert J.; Lehmann Hugo; Spanswick Simon C.; Sparks Fraser T.; Melvin Neal R. 《Canadian Metallurgical Quarterly》2006,60(2):166
We present an overview of two of our ongoing projects relating processes in the hippocampus to memory. We are trying to understand why retrograde amnesia occurs after damage to the hippocampus. Our experiments establish the generality of several new retrograde amnesia phenomena that are at odds with the consensus view of the role of the hippocampus in memory. We show in many memory tasks that complete damage to the hippocampus produces retrograde amnesia that is equivalent for recent and remote memories. Retrograde amnesia affects a much wider range of memory tasks than anterograde amnesia. Normal hippocampal processes can interfere with retention of a long-term memory stored outside the hippocampus. We conclude that the hippocampus competes with nonhippocampal systems during memory encoding and retrieval. Finally, we outline a project to understand and manipulate adult hippocampal neurogenesis in order to repair damaged hippocampal circuitry to recover lost cognitive functions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
The effect of three storage temperatures (0, -9 and -18 degrees C) of the kiwi-fruit pulp reduced pressure concentrate, by a period of 3 months, in the physical (soluble solids, water activity, consistency and color), chemistry (pH, acidity, ascorbic acid, chlorophyll and pheophytin) and sensorial (appearance, aroma, acidity, sweetness, color and flavor) characteristics were studied. The greater deterioration was produced in the stored pulp to 0 degree C, while to -9 degrees C there is no significative differences, on the other hand, the kiwi-fruit pulp stored to -18 degrees C maintained large part of the original characteristics. It was observed that while the temperature and storage time increased, vitamin C and chlorophyll contents decreased, varying significantly consistency, color and appearance of product. The rest of the analyzed variables did not present significative differences during storage. 相似文献
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The CATHEDRAL Silicon Compilers synthesize hardware for DSP algorithms specified in Silage, a high level applicative language. In order to optimize the results of the silicon compilation in terms of chip-area and/or throughput, the user often massages the specification applying transformations to the Silage code. To guarantee that the transformations preserve the behavior of the specified algorithm, the formal semantics of the specification language had to be defined. The semantics has been used to prove in HOL the correctness of the transformations and to prove properties of the specification. We are currently building a system where a menu of useful andcorrectness preserving transformations will be available to the user. In this system the user could choose appropriate transformations from the menu taking advantage of his creativity and expertise to interactively guide the silicon compiler, without the risk of introducing inconsistencies. This article describes the formalmulti-rate semantics of a substantial subset of Silage and illustrates some formally verified transformations. 相似文献
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The aim of this study was to compare growth curves of stature in indigenous and non-indigenous children belonging to two levels of poverty and to establish the onset and evolution of the deficit. Children of indigenous and non-indigenous background living in communities of extreme and low poverty in Chile were studied and their height-for-age Z-score from birth until 6 year of age were compared. Mean weight at birth was within normal range, and no differences were found in ethnicity and levels of poverty. Length at birth was below the reference with the exception of the non indigenous newborn from counties of low poverty. Deficit in growth showed an early start, furthermore in indigenous children belonging to the extreme poverty, is from birth and progress through the 18 months. At 72 months the deficit reached -1.1 z scores in the indigenous of the extreme poverty versus -0.7 in the non indigenous group. Children from the low poverty had a Z-score of -0.4 z scores at 72 months without differences between ethnias. Indigenous of the extreme poverty had less accumulative growth while the indigenous of the low poverty areas growth satisfactory without differences with the non indigenous. 相似文献
98.
This article introduces the CAM-Brain Machine (CBM), an FPGA based piece of hardware which implements a genetic algorithm (GA) to evolve a cellular automata (CA) based neural network circuit module, of approximately 1,000 neurons, in about a second, i.e., a complete run of a GA, with 10,000s of circuit growths and performance evaluations. Up to 65,000 of these modules, each of which is evolved with a humanly specified function, can be downloaded into a large RAM space, and interconnected according to humanly specified artificial brain architectures. This RAM, containing an artificial brain with up to 75 million neurons, is then updated by the CBM at a rate of 130 billion CA cells per second. Such speeds should enable real time control of robots and hopefully the birth of a new research field that we call brain building. The first such artificial brain, to be built in 2000 and beyond, will be used to control the behaviors of a life sized robotkitten called Robokitty. 相似文献
99.
Harrison Neil A.; Wilson C. Ellie; Critchley Hugo D. 《Canadian Metallurgical Quarterly》2007,7(4):724
Facial autonomic responses may contribute to emotional communication and reveal individual affective style. In this study, the authors examined how observed pupillary size modulates processing of facial expression, extending the finding that incidentally perceived pupils influence ratings of sadness but not those of happy, angry, or neutral facial expressions. Healthy subjects rated the valence and arousal of photographs depicting facial muscular expressions of sadness, surprise, fear, and disgust. Pupil sizes within the stimuli were experimentally manipulated. Subjects themselves were scored with an empathy questionnaire. Diminishing pupil size linearly enhanced intensity and valence judgments of sad expressions (but not fear, surprise, or disgust). At debriefing, subjects were unaware of differences in pupil size across stimuli. These observations complement an earlier study showing that pupil size directly influences processing of sadness but not other basic emotional facial expressions. Furthermore, across subjects, the degree to which pupil size influenced sadness processing correlated with individual differences in empathy score. Together, these data demonstrate a central role of sadness processing in empathetic emotion and highlight the salience of implicit autonomic signals in affective communication. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.