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151.
The past decade has witnessed an intensifying focus on the development of irrigation in sub-Saharan Africa. It follows a 20-year hiatus in the wake of disappointing irrigation performance during the 1970s and 1980s. Persistent low productivity in African agriculture and vulnerability of African food supplies to increasing instability in international commodity markets are driving pan-African agricultural investment initiatives, such as the Comprehensive Africa Agricultural Development Programme (CAADP), that identify as a priority the improvement in reliability of water control for agriculture. The paper argues that, for such initiatives to be effective, there needs to be a re-appraisal of current dynamics of irrigation development in sub-Saharan Africa, particularly with respect to the role of small-scale producers’ initiatives in expanding irrigation. The paper reviews the principal forms such initiatives take and argues that official narratives and statistics on African irrigation often underestimate the extent of such activities. The paper identifies five key characteristics which, it argues, contradict widely held assumptions that inform irrigation policy in Africa. The paper concludes by offering a definition of ‘farmer-led irrigation’ that embraces a range of interaction between producers and commercial, government and non-government agencies, and identifies priority areas for research on the growth potential and impact of such interactions and strategies for their future development.  相似文献   
152.
Since the mid-twentieth century, elite political behavior in the United States has become much more nationalized. In Congress, for example, within-party geographic cleavages have declined, roll-call voting has become more one-dimensional, and Democrats and Republicans have diverged along this main dimension of national partisan conflict. The existing literature finds that citizens have only weakly and belatedly mimicked elite trends. We show, however, that a different picture emerges if we focus not on individual citizens, but on the aggregate characteristics of geographic constituencies. Using biennial estimates of the economic, racial, and social policy liberalism of the average Democrat and Republican in each state over the past six decades, we demonstrate a surprisingly close correspondence between mass and elite trends. Specifically, we find that: (1) ideological divergence between Democrats and Republicans has widened dramatically within each domain, just as it has in Congress; (2) ideological variation across senators’ partisan subconstituencies is now explained almost completely by party rather than state, closely tracking trends in the Senate; and (3) economic, racial, and social liberalism have become highly correlated across partisan subconstituencies, just as they have across members of Congress. Overall, our findings contradict the reigning consensus that polarization in Congress has proceeded much more rapidly and extensively than polarization in the mass public.  相似文献   
153.
To what extent do partisan media sources shape public opinion? On its face, it would appear that the impact of partisan media is limited, given that it attracts a relatively small audience. We argue, however, that its influence may extend beyond its direct audience via a two‐step communication flow. Specifically, those who watch and are impacted by partisan media outlets talk to and persuade others who did not watch. We present experimental results that demonstrate this process. We therefore show that previous studies may have significantly underestimated the effect of these outlets. We also illustrate that how the two‐step communication flow works is contingent upon the precise composition of the discussion group (e.g., is it consistent of all fellow partisans or a mix of partisans?). We conclude by highlighting what our results imply about the study of media, preference formation, and partisan polarization.  相似文献   
154.
Abstract

This paper compares the reasons given by three South-east Asian states (Laos, Thailand and Vietnam) for choosing to suppress opium production. While external pressure, often from the US or United Nations (UN)/League of Nations, is the most commonly identified reason in the literature, and was experienced in each case, it was not by itself sufficient to motivate states into action. All three cases were motivated by religious or ideological opposition to drug consumption or trade, rural development, state extension and concern for increasing domestic drug consumption. Apprehension about rising drug consumption often possessed racial or chauvinistic elements. The development of export commodities, environmental protection and national security were also identified in one or two cases. The paper concludes by hypothesising that economic and/or security considerations underlie all choices to suppress illicit drug crops.  相似文献   
155.
From January 2015 to December 2017, approximately 1.6 million migrants crossed the Mediterranean to reach Europe. The death toll was dramatic, with almost 15,000 drowning. In response to the void left by the ending of the Italian-led Mare Nostrum mission, several non-governmental organizations (NGOs) launched their own search and rescue (SAR) operations, rescuing over 110,000 migrants. In this article, we argue that states have the responsibility not only to coordinate, but also to directly provide adequate SAR operations in the Mediterranean, and that these responsibilities are presently being abdicated. Although much criticism of NGO maritime rescuing operations is misplaced, non-governmental SAR has notable limitations, and states are ultimately responsible for this shortfall.  相似文献   
156.
This article develops and elaborates on three core points. First, as with research into other social science themes, it is argued that it is necessary to apply the logic of correlation and causality to the study of political violence. Second, it highlights the critical disjuncture between attitudes and behaviors. Many or most individuals who support the use of political violence remain on the sidelines, including those who sympathize with insurgents in Afghanistan (reportedly 29 percent in 2011), and those supportive of “suicide attacks” in the Palestinian Territories (reportedly reaching 66 percent in 2005). Conversely, those responsible for such behaviors are not necessarily supportive of the ostensible political aims. Third, it is argued that the motives that drive these attitudes and behaviors are often (or, some would argue, always) distinct. While the former are motivated by collective grievances, there is substantial case study evidence that the latter are commonly driven by economic (e.g., payments for the emplacement of improvised explosive devices), security-based (i.e., coercion) and sociopsychological (e.g., adventure, status, and vengeance) incentives. Thus, it is necessary for the research community to treat attitudes and behaviors as two separate, albeit interrelated, lines of inquiry.  相似文献   
157.
158.
The transnational agrarian social movement Vía Campesina is campaigning to have the United Nations negotiate and implement a Declaration, and eventually an International Convention, on Peasants' Rights. This article analyzes the origins and demands of the campaign and the place of the claimed rights in international law. Peasant organizations hope to follow in the footsteps of indigenous peoples' movements that participated in the negotiations preceding the 2007 UN Declaration on the Rights of Indigenous Peoples. The peasants' rights campaign has succeeded in linking its demands to discussions of the right to food in the United Nations, where concern is growing over the approach of the 2015 target for realizing the Millennium Development Goals, in particular the halving of the numbers of people suffering from hunger. The campaign is likely to face stiff resistance from powerful UN member states, but could achieve substantial advances even if the path to a convention is difficult or never completed.  相似文献   
159.
160.
Few studies have examined risk factors of childhood and early adolescent depressive symptomatology trajectories. This study examined self-report depressive symptomatology across a 6-year time period from 2nd to 8th grade to identify latent groups of individuals with similar patterns of depressive phenomena in a sample of 951 children (440 girls, 511 boys). Analyses, using semiparametric group modeling (SGM), identified 5 trajectory groups for girls and boys: low depressed stables, low depressed risers, mildly depressed stables, moderately depressed changers, and moderately depressed risers. Individual risk factors, with the exception of shy/withdrawn behavior, were significantly different across trajectory group membership for boys and girls, as was low-income status for boys. Boys in the low depressed and mildly depressed stable trajectory groups had significantly higher levels of antisocial behavior, attention problems, and lower social competency compared to girls in similar groups. These results suggest that universal prevention programs implemented in early elementary school that target selected risk factors may be helpful in reducing future adolescent mental health problems, specifically depressive symptomatology.  相似文献   
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