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Conflict monitoring by the anterior cingulate cortex (ACC) has been posited to signal a need for greater cognitive control, producing neural and behavioral adjustments. However, the very occurrence of behavioral adjustments after conflict has been questioned, along with suggestions that there is no direct evidence of ACC conflict-related activity predicting subsequent neural or behavioral adjustments in control. Using the Stroop color-naming task and controlling for repetition effects, we demonstrate that ACC conflict-related activity predicts both greater prefrontal cortex activity and adjustments in behavior, supporting a role of ACC conflict monitoring in the engagement of cognitive control.  相似文献   
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The economics of harvesting wheat based on input management zones in the northern wheatbelt of Western Australia was studied using a simulated field of regular dimensions with varying zone sizes and layouts. Fertilizer application rates and crop yield and quality data from field trials of input management were used to estimate the gross crop revenue and harvesting costs from the different field layouts and zone combinations. As a general observation there was no consistency in the results; harvesting by zone generated more gross income in some combinations of field layout and yield quantity scenarios, but not in others. However, there were key factors in determining whether it was profitable to harvest by zone. These were prior knowledge of the potential yield and quality characteristics of grain from each zone in a field, and the layout of zones within a field.  相似文献   
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Advocates of environmental sustainability and social justice increasingly pursue their goals through the promotion of so-called “green” products such as locally grown organic produce. While many scholars support this strategy, others criticize it harshly, arguing that environmental degradation and social injustice are inherent results of capitalism and that positive social change must be achieved through collective action. This study draws upon 18 months of ethnographic fieldwork at two farmers markets located in demographically different parts of the San Francisco Bay Area to examine how market managers, vendors, and regular customers negotiate tensions between their economic strategies and environmental sustainability and social justice goals. Managers, vendors, and customers emphasize the ethical rather than financial motivations of their markets through comparisons to capitalist, industrial agriculture and through attention to perceived economic sacrifices made by market vendors. They also portray economic strategies as a pragmatic choice, pointing to failed efforts to achieve justice and sustainability through policy change as well as difficulties funding and sustaining non-profit organizations. While market managers, vendors, and customers deny any difficulties pursuing justice and sustainability through local economics, the need for vendors to sustain their livelihoods does sometimes interfere with their social justice goals. This has consequences for the function of each market.
Alison Hope AlkonEmail:

Alison Hope Alkon   is a Ph.D. candidate in the Department of Sociology at the University of California, Davis. Her research examines how efforts to create environmental protection and social justice operate in a market context.  相似文献   
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