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491.
The effect that the length of electoral periods has on the behavior of elected officials is examined. The hypothesis is that the longer the period between elections the less responsible or the more independent representatives will behave relative to the desires of their polity. The hypothesis is tested by examining the behavior of U.S. Senators. It is found that their independence follows a cyclical behavior which conforms to the electoral period. As a result it is by no means clear that decreasing the frequency of elections reduces the cost of elections. The effect of this independence cost on the optimal frequency of elections is discussed. 相似文献
492.
Elizabeth Rigby Rebecca M. Ryan Jeanne Brooks‐Gunn 《Journal of policy analysis and management》2007,26(4):887-908
Using data from the Child Care Supplement to the Fragile Families and Child Wellbeing Study, we test associations between the quality of child care and state child care policies. These data, which include observations of child care and interviews with care providers and mothers for 777 children across 14 states, allow for comparisons across a broader range of policy regimes and care settings than earlier research on this topic. Using multilevel linear and logistic models, we found that more generous subsidy policies (that is, greater investment, higher income eligibility) were positively associated with the quality of care in nonprofit child care centers, as well as with the use of center care. The stringency of regulations (that is, teacher education requirements, teacher‐child ratios/thresholds) was also associated with both quality and type of care, but in more complex ways. Higher teacher training requirements were positively associated with the quality of both family child care and nonprofit centers, while more stringent regulations decreased the number of children attending center care. No links were found between state policies and the quality of for‐profit center care. The implications for policy makers, advocates, and policy analysts are discussed. © 2007 by the Association for Public Policy Analysis and Management 相似文献
493.
Maíra Kerpel dos Santos PhD Alexander Acosta PhD Ryan Capote BS Bakhtawar Tabassam BS James Ley PhD Martin Quirke PhD José Almirall PhD 《Journal of forensic sciences》2023,68(4):1162-1177
The 4- Aminophenol (4-AP) colorimetric test is a fast, easy-to-use, and cost-effective presumptive assay of cannabis plant material producing different chromophores with THC-rich cannabis (blue color) and with CBD-rich cannabis (pink color). The main drawback of the 4-AP test is a brief observation window where the color rapidly changes to black, limiting the utility of the test. We now report for the first time, the identification of the product chromophores between 4-AP and CBD/THC as well as propose an explanation and a solution for the color degradation of the chromophores. The identification of the chromophores is provided by spectroscopic (UV–Vis), chromatography, and mass spectrometry (TLC and LC-QToF-MS). Oxidation of excess 4-AP (Reagent A) in the presence of NaOH (Reagent B) produces the black color observed for the previously reported 4-AP tests and reported in the literature. The adjustment of reactants concentrations and volumes of 4-AP:THC/CBD to a 1:1 ratio significantly reduces the black oxidation by-product and increases the observation window up to 2 h instead of the previously reported 5–10 min. For the first time, mass spectrometry and chromatography confirmed that the reaction of THC and CBD with 4-AP produced chromophores with m/z (M + H) = 420, consistent with proposed indophenol structures. The TLC method developed confirmed the separation between CBD and THC chromophores. The specificity of the test is also reported, showing false positive results for the presence of THC (blue color) for samples of thyme and oregano. LDA and SIMCA models showed that the optimized 4-AP procedure performs better than the previously reported 4-AP color test. 相似文献
494.
495.
Richard W. Ryan 《国际公共行政管理杂志》2013,36(1):77-89
Hope, Kempe Ronald. THE DYNAMICS OF DEVELOPMENT AND DEVELOPMENT ADMINISTRATION, Greenwood Press, Westport, Connecticut, 1984, 128 pp. Paul, Samuel. MANAGING DEVELOPMENT PROGRAMS: THE LESSONS OF SUCCESS, Westview Press, Boulder, Colorado, 1982, 247 pp., $20 相似文献
496.
497.
T. K. Ahn Robert Huckfeldt Alexander K. Mayer John Barry Ryan 《American journal of political science》2013,57(2):357-373
Citizens minimize information costs by obtaining political guidance from others who have already assumed the costs of acquiring and processing political information. A problem occurs because ideal informants, typically characterized by the joint presence of political expertise and shared viewpoints, are frequently unavailable or rare within the groups where individuals are located. Hence, individuals must often look beyond their own group boundaries to find such informants. The problem is that obtaining information from individuals located beyond their own groups produces additional costs. Moreover, the availability of ideal informants varies across groups and settings, with the potential to produce (1) context‐dependent patterns of informant centrality, which in turn generate (2) varying levels of polarization among groups and (3) biases in favor of some groups at the expense of others. The article's analysis is based on a series of small‐group experiments, with aggregate implications addressed using a simple agent‐based model. 相似文献
498.
Maria Ryan 《Intelligence & National Security》2013,28(2):286-315
In 2003 the Pentagon's Office of Special Plans employed a hypothesis-based methodology to deliver the now discredited intelligence that justified the Iraq war. The 1976 ‘Team B’, which was also heavily influenced by neoconservatives and used the same methodology, has been recognized as a precedent. There is, however, another precedent, the 1998 Rumsfeld Commission, which challenged CIA predictions on the ballistic missile threat to the US. Lobbied for by many of the same conservatives and neoconservatives, the Commission used the same analytical style as Team B and the OSP. The now discredited intelligence on Iraq was not a ‘failure’ or ‘mistake’, but a method, tried and tested by the right, of challenging the CIA on political grounds. 相似文献
499.
500.
Ryan Hookano M.S. Ronald A. Brunelli A.A.S. Robert Stoppacher M.D. 《Journal of forensic sciences》2013,58(6):1628-1632
With the increased popularity of online social networking services (SNS) such as Facebook, LinkedIn, Twitter, and Google+, we propose that a wealth of new resources is available for medicolegal death investigation. Recognizing this potential, we identified cases in which social media had been useful in the past in our office and asked our investigative staff to consider using social media in current cases. These cases provided illustrative examples for this primer regarding how information from SNS was used in death investigations in our office. Information gleaned from online social media aided in establishing preliminary identification of a decedent, locating next‐of‐kin, investigating the circumstances of death as relevant to the manner of death, corroborating eyewitness accounts, and providing information relevant to time of death. Potential pitfalls were identified, such as shared accounts or online impostors. SNS proved useful to the medicolegal death investigator and medical examiner, so long as their limitations were recognized. 相似文献