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21.
ABSTRACT

Although India’s cotton sector has been penetrated by various input- and capital-intensive methods, penetration by herbicide has been largely stymied. In Telangana State, the main obstacle has been the practice of ‘double-lining’, in which cotton plants are spaced widely to allow weeding by ox-plow. Path dependency theory primarily explains the persistence of sub-optimal practices, but double-lining is an example of an advantageous path for cash-poor farmers. However, it is being actively undermined by parties intent on expanding herbicide markets and opening a niche for next-generation genetically modified cotton. We use the case to explicate the role of treadmills in technology ‘lock-in’. We also examine how an adaptive locked-in path may be broken by external interests, drawing on recent analyses of ‘didactic’ learning by farmers.  相似文献   
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Research into fingermark enhancement techniques has traditionally used visual comparisons and qualitative methods to assess their effectiveness based on the quality of the developed fingermark. However, with increasing research into the optimisation of these techniques the need for a quantitative evaluative method has arisen. Parameters for acceptable fingerprint quality are not well defined and generally encompass clear, sharp edges and high levels of contrast between the fingermark ridges and background material. Using these current parameters, a conclusive measurement of fingerprint quality and thus the effectiveness of development techniques cannot be achieved.This study presents a model through which an aspect of fingerprint quality can be objectively and impartially measured based on a relative contrast index, constructed through measuring the reflective intensity of the fingermark ridges against the background material. Using a fibre-optic spectrophotometer attached to a microscope with axial illumination, the intensity counts of the ridge detail and background material were measured and a logarithmic contrast index constructed. The microscope and spectrophotometer parameters were experimentally tested using a standard colour resolution chart with known reflective properties. The protocol was successfully applied to four sample groups: black inked fingerprints on white paper; latent fingermarks on white paper developed separately with ninhydrin and physical developer; and fingermarks in blood deposited on white tiles and enhanced with amido black. The contrast indices obtained quantitatively reflect the level of contrast and provide an indication of fingerprint quality through a numerical representation rather than previous qualitative methods. It has been suggested that the proposed method of fingerprint quantification may be viable for application in the forensic research arena as it allows the definitive measurement of contrast to aid the evaluation of fingermark detection and enhancement techniques.  相似文献   
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During the past two decades Nigeria has invested heavily in scientific research, by developing country standards. Yet these investments at best have had only marginal impacts on the activities of the production and service sectors even though there are many priority development activities which could benefit from inputs from Nigerian researchers. At the national level efforts to direct or even co-ordinate the planning and budgeting of research have been seriously hampered by frequent changes in organizational responsibilities and by repeated budget cuts. Historically, the activities of the federal research institutes have been poorly tuned to the interests and capabilities of the potential users of their research products. Neither these institutes nor the universities with research activities are in a position to develop products or processes which can compete with imported technologies that are saturating the economy. However, the research institutes, and to a lesser extent the universities, should make greater contributions in applying science to improved use of the nation's natural resource endowments, although significant changes in research management at the project level are needed if this objective is to be realized. The Government should provide incentives to the multinational companies operating in Nigeria to develop joint programmes with the research institutes and universities as one mechanism for diffusing the administrative and technical capabilities of the companies. Meanwhile, selected public sector enterprises should be encouraged to expand technological innovation efforts which could be directly applied to their production activities.  相似文献   
25.
Opinion Taking within Friendship Networks   总被引:2,自引:0,他引:2  
Communication within friendship networks can provide gains in efficiency that help individuals enrich their understanding of politics. Through two panel survey experiments, we demonstrate that the dissemination of an individual's opinion about the hazards posed by public policies can have both durable and significant effects on the policy judgments of friends. These effects are conditioned by both the content of the communication and the recipient's level of political awareness. Opinions emphasizing potential risks carry more weight than those that attempt to alleviate concerns about potential risks. Moreover, opinion transmission is more effective for subjects who are less politically aware when policy issues are salient; but when the political issue is more esoteric, friends who are more politically aware evidence greater opinion change.  相似文献   
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Abstract

This paper provides a comprehensive evaluation of market segmentation and lender/purchaser specialization in the primary and secondary mortgage markets. It describes and assesses the 1990 Home Mortgage Disclosure Act (HMDA) data, which for the first time provide detailed information on the borrower and neighborhood racial and income characteristics of mortgage loan originations and securitizations in the primary and secondary mortgage markets. Evidence presented in the paper indicates that home purchase loan origination rates for black applicants—and, to a lesser degree, Hispanic applicants—appear to be significantly lower than those of other racial or ethnic groups. Similarly, the HMDA data reveal that home purchase mortgage origination rates in predominantly minority census tracts are significantly lower than those in predominantly white neighborhoods. The HMDA data also indicate a striking reliance of black borrowers on government‐backed forms of mortgage credit.

The paper further reveals that secondary market loan purchase distributions arrayed by borrower and neighborhood characteristics generally reflect those of home mortgage originations. The borrower and locational characteristics of home purchase loans acquired by the Government National Mortgage Association (GNMA) directly reflect that agency's legislated specialization in government‐backed loans, whereas the characteristics of loans acquired by Fannie Mae and Freddie Mac for the most part derive from the borrower and geographic composition of conventional home purchase loan originations. Findings of analyses of HMDA data raise concern regarding the access of minority and low‐income households and neighborhoods to mortgage finance. Those results also raise some question as to whether the federally chartered agencies in the secondary market are adequately promoting the availability of mortgage credit to low‐ and moderate‐income and minority households.  相似文献   
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Public concern about the earnings‐related Canada Pension Plan has forced the Canadian government to move toward fuller funding, a new investment policy, and changes to benefits and administration. Together, the three initiatives, and particularly the first two, amount to a modest degree of marketization. The assumption behind the reform is that the Canada Pension Plan will remain public and mandatory but the change will create a board and an investment policy which are more sensitive to market pressures and less amendable to government interference. The Canada Pension Plan is one of three tiers of support for the elderly in retirement. It is a contributory social insurance scheme which protects against loss of income. The other two are a social allowance (Old Age Security) as well as an income tested benefit (Guaranteed Income Supplement) which provide basic income support and employment based retirement pension plans as well as group and individual registered retirement savings plans which supplement the other two tiers on a voluntary basis. This article examines the reform of the Canada Pension Plan. After a brief examination of Canada's retirement benefits in an international context, the article summarizes recent debates in Canada, government policies to develop fuller funding and new investment strategies, and reflections on possible developments in the future.  相似文献   
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