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1.
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   
2.
In this paper seven hypotheses to explain variation in central bank independence across countries are tested. The predictions based upon the theory that delegation of authority by politicians to the central bank is used as a commitment device are not supported: central bank independence is not higher the larger the employment motivated inflationary bias, the higher political instability or the larger the government debt. Central bank independence is positively related to historical inflation experience and negatively with political instability. We do only find limited support for the view that countries with a universal banking system and countries whose central banks do not regulate financial institutions have more independent central banks.  相似文献   
3.
In a double-blind placebo controlled study on psychomotor skills important for car driving (Study 1), a 75 mg dose of +/- 3,4-methylenedioxymethamphetamine (MDMA) was administered orally to 12 healthy volunteers who were known to be recreational MDMA-users. Toxicokinetic data were gathered by analysis of blood, urine, oral fluid and sweat wipes collected during the first 5h after administration. Resultant plasma concentrations varied from 21 to 295 ng/ml, with an average peak concentration of 178 ng/ml observed between 2 and 4h after administration. MDA concentrations never exceeded 20 ng/ml. Corresponding MDMA concentrations in oral fluid, as measured with a specific LC-MS/MS method (which required only 50 microl of oral fluid), generally exceeded those in plasma and peaked at an average concentration of 1215 ng/ml. A substantial intra- and inter-subject variability was observed with this matrix, and values ranged from 50 to 6982 ng/ml MDMA. Somewhat surprisingly, even 4-5h after ingestion, the MDMA levels in sweat only averaged 25 ng/wipe. In addition to this controlled study, data were collected from 19 MDMA-users who participated in a driving simulator study (Study 2), comparing sober non-drug conditions with MDMA-only and multiple drug use conditions. In this particular study, urine samples were used for general drug screening and oral fluid was collected as an alternative to blood sampling. Analysis of oral fluid samples by LC-MS/MS revealed an average MDMA/MDEA concentration of 1121 ng/ml in the MDMA-only condition, with large inter-subject variability. This was also the case in the multiple drug condition, where generally, significantly higher concentrations of MDMA, MDEA and/or amphetamine were detected in the oral fluid samples. Urine screening revealed the presence of combinations such as MDMA, MDEA, amph, cannabis, cocaine, LSD and psilocine in the multiple-drug condition.  相似文献   
4.
Tinggaard Svendsen  Gert 《Public Choice》1999,101(1-2):109-128
Public Choice - If there is to be environmental regulation, what kind of regulation would the main interest groups then prefer? This political distortion must be taken into account when designing...  相似文献   
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6.
The Global Information Society (GIS) has in recent years been high on the political agenda of Western countries. These countries have been concerned with the development of Information Infrastructures in order to achieve the Information Society. In the West there has been a broad consensus about the framework in which the development of the GIS needs to take place. On both national and international levels a framework has to be established which supports competition, encourages private investment, supports flexible regulatory framework and allows for open access to networks. Recently this dominant scenario has been transposed as the appropriate scenario for the development of Information Infrastructures in the developing world. This article sets out to give an overview of GIS policy in a developmental context. It elaborates on recent policy initiatives in the area. At the international level it critically analyses changes in the communications industries and in the global economy. At the national level it critically analyses the assumptions of the dominant scenario and its proposed strategy for achieveing the GIS.  相似文献   
7.
Why does bureaucratic corruption occur in the EU system? Several examples suggest that bureaucratic corruption exists and that the Commission’s anti-fraud agency, OLAF, is not a fully independent authority. We thus develop a novel interpretation of the principal-supervisor-agent model to cope with non-independent anti-fraud units. This model shows that corruption is likely to occur when the expected value to the client from bribing the agent is larger than the expected value to the principal of truth-telling by the supervisor. Overall, this analysis points to the risks of flawed incentives and the lack of institutional independence among principal, agent, supervisor and client. Our main policy recommendations as a result of these findings are that OLAF should be placed outside the Commission, and that whistleblowers should receive adequate protection.  相似文献   
8.
Whereas political scientists tend to make binary distinctions between sovereign states and subnational units, in recent decades the number of a third, hybrid category of federacies or non-sovereign jurisdictions has strongly increased. In this paper, we explore the benefits and downsides of non-sovereignty from the perspective of these territories’ inhabitants. We zoom in on the six islands of the Dutch Caribbean, which in 2010 experienced a profound change in their political status. Using data from two large-scale opinion surveys that we conducted in 1998 and 2015, respectively, we show that the population of the Dutch Caribbean islands maintains a highly ambiguous attitude towards the non-sovereign status. While many respondents appreciate the material benefits of the enduring link with the metropolis, there are significant emotional and ideational objections to this relationship. These findings are embedded in broader scholarly discussions about the position of decentralized and peripheral jurisdictions vis-à-vis their administrative core.  相似文献   
9.

How robust is the welfare state when confronting open borders? To answer that question, we develop an evolutionary game-theoretic model combined with an ingroup–outgroup model. The simulations reveal that welfare states in general will transform into low-welfare societies unless the societies in time generate a sufficiently large amount of social recognition of the reciprocators in such a crisis. The recognition implies that the “always cooperators” in favour of supportive policies towards free riders need to step down and hand over privileges to those willing to reciprocate, namely the “willing punishers”. The open-border society is modelled by letting a small amount of random types enter the society each year. Interestingly, it is not the defectors who compromise high-welfare societies. Instead, it is the excessive presence of cooperators who crowd out the reciprocators, thus making society increasingly vulnerable to free riding. This accentuates the need for timely recognition and actions against the risk of moving towards a low-welfare society.

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10.
Forensic entomotoxicology studies the usefulness of insects as alternative toxicological samples. Use of insects as alternative matrix for drug detection is well documented and recommended when conventional matrices such as blood, urine or internal organs are no longer available. However, several limitations of entomotoxicology have been highlighted, especially concerning interpretation of the drug concentrations in insects on human forensic cases. In addition, the lack of knowledge in pharmacokinetic of drugs in insects, large variability of experimental set-up and toxicological analysis compromise the utility of this science. This review focuses on the current knowledge of factors influencing drug detection in insects. Reasons for the current limitations, but also recommendations for future research are discussed and proposed in this paper.  相似文献   
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