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The marine environment includes the nutrient-rich coastal waters, relatively nutrient-poor open oceanic waters, coral reef atolls, metal-rich hydrothermal vent fluids with temperatures of 200–350°C, cold-seeps, estuaries, mangrove swamps, intertidal beaches and rocky shores. Oceans are home to some of themost diverse and unique life forms. This article is an attempt to introduce some of the fundamentals of biologicaloceanography andmarine biologyto describe life in the sea.  相似文献   
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Rats confronted with the onset of a light gradient display a transient increase in locomotion called theactivity response (AR) and a dark preference (Godsil & Fanselow, 2004). These experiments demonstrate that the magnitude of the AR can be blunted with Pavlovian fear-conditioning procedures via associative and nonassociative fear. Although manifested in decreased locomotion, the blunted AR effect was not due to increased freezing or immobility behaviors. Instead, rats displayed reduced rearing and an increase in a class of behaviors calledstationary activity. These results suggest that the lighting differential supplied by the cue influences the topography of defensive behavior and reduces the expression of freezing. This procedure provides a means by which to examine learned and unlearned defensive responses to the same stimulus.  相似文献   
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In this paper, the problem of stochastic stability analysis is considered for piecewise homogeneous Markovian jump neural networks with both discrete and distributed delays by use of linear matrix inequality (LMI) method. Based on a Lyapunov functional that accounts for the mixed time-delays, a delay-dependent stability condition is given, which is formulated by LMIs and thus can be easily checked. Some special cases are also investigated. Finally, a numerical example is given to show the validness of the proposed result.  相似文献   
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Increasingly, firms recognize the strategic implications of front-end product design for improving total cost effectiveness. Computer-aided design (CAD) is becoming firms’ competitive weapon beyond its traditional function as a product design tool. Yet, it is unclear how the full potential of IT system, particularly the usage patterns of 3D CAD system, may be realized through organizational capabilities. This paper presents a model of IT system configurations and CAD usage patterns. Next, a typology of IT system configurations is presented based on (1) the degree of CAD integration between assembly makers and suppliers and (2) the structure of product design information (i.e., product architecture). The product architecture of four electronic firms illustrates that information integration through organizational capabilities is more important than IT investment itself. The findings suggest that a Korean firm accomplishes a greater level of IT integration compared to the other two Japanese firms and thus attain better market performance. This study offers valuable insight on effective IT integration strategy for competitive advantage in the global market.  相似文献   
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