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A Green Revolution for Africa is emerging after decades of neglect of Africa’s agricultural systems. To counter these years of neglect, the then United Nations Secretary-General Kofi Annan called for “a uniquely African Green Revolution”. Since then, a number of initiatives have emerged or are emerging to realize this important vision. As more money and attention galvanizes much-needed action on the African Green Revolution, a vigorous debate is required to ensure that the mission of improving food security on the world’s poorest continent is achieved in the most effective, comprehensive and inclusive manner possible. The African Green Revolution cannot be limited to increasing yields of staple crops but must be designed as a driver of sustainable development, which includes gender empowerment and nutrition elements. This paper first reviews the Asian Green Revolution’s successes and shortcomings from a nutrition and gender perspective and then outlines what the global community can do to ensure that some of the limitations of the Asian Green Revolution, specifically with regard to nutrition and gender, are not repeated. 相似文献
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Jessica J. Sherman Brent A. Murry Daelyn A. Woolnough David T. Zanatta Donald G. Uzarski 《Journal of Great Lakes research》2013
Populations of native unionids have been in steady decline over the past century. The invasion of dreissenid mussels (Dreissena polymorpha and Dreissena rostriformis bugensis) in the mid-1980's impacted already imperiled unionid populations by greatly increasing their regional extinction rates. A selection of Great Lakes coastal wetlands around Michigan was surveyed to locate remnant populations of native unionids. Physical and chemical parameters were measured in coastal wetlands to evaluate the importance of these habitat parameters to remnant unionid assemblages. We assessed fouling rates by dreissenids on unionids and used artificial substrates to estimate dreissenid colonization densities. Live unionids were found in coastal wetlands of the Les Cheneaux Islands, the Lake St. Clair delta, and North Maumee Bay with significantly higher unionid fouling in the Les Cheneaux Islands compared to the other two sampling areas (F2,76 = 4.97, p = 0.0095). No live unionids were documented in Beaver Island, Garden Island, Grand Traverse Bay, or Saginaw Bay wetlands. Dreissena colonization densities on artificial substrates averaged 19,213 m− 2 at one site in North Maumee Bay, and 10,425 m− 2 in Saginaw Bay, but no colonization occurred in the wetlands of Beaver Island, Garden Island, the Les Cheneaux Islands, or Grand Traverse Bay while Dreissena presence in the open water of these regions was evident. Dreissena colonization densities on artificial substrates increased with measures of anthropogenic disturbance and decreased with higher water level fluctuations and aerial exposure. Specific conductance, turbidity, and magnitude of water level fluctuations were important predictors of Dreissena colonization on artificial substrates. 相似文献
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Carlyon Robert P.; Deeks John M.; Shtyrov Yury; Grahn Jessica; Gockel Hedwig E.; Hauk Olaf; Pulvermüller Friedemann 《Canadian Metallurgical Quarterly》2009,35(6):1898
The authors show that a narrowband noise (NBN) is perceived as longer when presented immediately after a wideband noise (WBN), compared to when the WBN is absent. This effect depended on the WBN’s frequency spectrum overlapping that of the NBN, and it increased as the duration of the WBN increased up to 300 ms. It decreased when a silent gap was introduced between the WBN and NBN, but remained significant for an easily detectable gap of 40 ms. A correlate of the effect was observed in the mismatch negativity (MMN) to a deviant stimulus, consisting of a WBN + NBN, presented in a sequence of more common isolated WBNs. The MMN latency was longer for an on-frequency than for an off-frequency WBN; and, more importantly, the size of this difference correlated across participants with the difference in perceived duration. A rhythm-adjustment experiment showed that the presence of an on-frequency WBN immediately preceding a tone caused that tone to be heard as starting earlier than when the WBN was absent. The results are discussed in relation to the continuity illusion and models of duration encoding. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Tracy Jessica L.; Robins Richard W.; Schriber Roberta A. 《Canadian Metallurgical Quarterly》2009,9(4):554
In 2 studies, the authors developed and validated of a new set of standardized emotion expressions, which they referred to as the University of California, Davis, Set of Emotion Expressions (UCDSEE). The precise components of each expression were verified using the Facial Action Coding System (FACS). The UCDSEE is the first FACS-verified set to include the three “self-conscious” emotions known to have recognizable expressions (embarrassment, pride, and shame), as well as the 6 previously established “basic” emotions (anger, disgust, fear, happiness, sadness, and surprise), all posed by the same 4 expressers (African and White males and females). This new set has numerous potential applications in future research on emotion and related topics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
Creativity is commonly defined as the novel and useful combination of concepts previously thought to be unrelated. Fundamentally, this process rests on the ability to judge relatedness between concepts. The authors conducted an experiment to test the connection between divergent thinking ability and the speed of judging relatedness. Our results demonstrated that people with higher divergent thinking ability are faster in judging whether two concepts are related or unrelated. In real life, this can lead to a substantial advantage in the number of potentially useful relationships that could be assessed per unit of time. Equally important, there was no link between IQ and speed of judging relatedness. These results are interpreted in relation to a recently proposed model of creative cognition suggesting that creative people are faster in information processing under conditions of low ambiguity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
Tracy Jessica L.; Robins Richard W.; Sherman Jeffrey W. 《Canadian Metallurgical Quarterly》2009,96(6):1206
The present research surveyed a group of editors and editorial board members of personality and social psychology journals to examine the practice of psychological science in their field. Findings demonstrate that (a) although personality and social researchers tend to use many of the same approaches, methods, and procedures, they nonetheless show average differences in each of these domains, as well as in their overarching theoretical aims and perspectives; (b) these average differences largely conform to social and personality researchers’ stereotypes about each subgroup; (c) despite their methodological and philosophical differences, the 2 subgroups study many of the same research topics; and (d) the structure of social–personality research practices can be characterized as having 2 independent factors, which closely correspond to L. J. Cronbach’s (1957) correlational and experimental “streams of research.” (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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David del Valle-Agudo Javier Calle-Gómez Dolores Cuadra-Fernández Jessica Rivero-Espinosa 《Interacting with computers》2012,24(2):78-90
Human interaction develops as an exchange of contributions between participants. The construction of a contribution is not an activity unilaterally created by the participant who produces it, but rather it constitutes a combined activity between the producer and the rest of the participants who take part in the interaction, by means of simultaneous feedback. This paper presents an incremental approach (without losing sight of how turns are produced throughout time), in which the interpretation of contributions is done as they take place, and the final generated contributions are the result of constant rectifications, reformulations and cancellations of the initially formulated contributions. The Continuity Manager and the Processes Coordinator components are proposed. The integration of these components in natural interaction systems allow for a joint approach to these problems. Both have been implemented and evaluated in a real framework called LaBDA-Interactor System which has been applied to the “dictation domain”. We found that the degree of naturalness of this turn-taking approach is very close to the human one and it significantly improves the interaction cycle. 相似文献