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81.
M. Henry Robison 《The Annals of Regional Science》1997,31(3):325-351
In this paper we outline an I-O modeling approach tailored to the needs of rural area analysis. We cover four essential features.
First, the rural area I-O model must convey an individual community focus. Second, the household sector must be defined in
a manner that specifically captures the great openness of rural community economies. Third, the model should offer a degree
of closure that provides an assessment of the community economic base. And finally, the rural community I-O model must be
defined to include estimates of intercommunity trade, and intercommunity multiplier effects. Having laid the theoretical foundations,
we identify subcounty data sources, and describe a collection of nonsurvey and hybrid approaches for estimating model components.
The community I-O approach is illustrated next, with an empirical example from central Idaho. The paper closes with a discussion
that considers the implications of community I-O in other contexts, including I-O analysis in less developed countries, and
in addressing modeling issues in larger nonrural regions.
Received: 7 March 1996 / Accepted in revised form: 26 February 1997 相似文献
82.
This study investigated the association between caries status and sealant need at a prior survey and subsequent sealant use in a Medicaid program. Clinical data from a 1986-87 statewide epidemiological survey (N = 8026) representative of North Carolina (NC) schoolchildren (grades K-12) were linked with all NC Medicaid dental claims submitted during 1987-92, yielding 570 children in the survey who had at least one dental visit during 1987-1992. From the 570, 390 children were included: 71 who received sealants (S) and 319 who received non-sealant care (NS). Children were excluded based on age, having preexisting sealants, or having no sealant-eligible molars or premolars. S and NS were compared on baseline dfs, DMFS, and sealant need, controlling for the patient's age, number of visits, and the provider's propensity to seal. At all ages, NS was twice as likely to have had prior dfs or DMFS (OR = 2.04, 95% CI = 1.15, 3.70). The association between sealant receipt and prior sealant need varied by age. At 6 to 11 years, S and NS had equal likelihood of sealant need (OR = 1.41, 95% CI = 0.62, 3.18). At 12 to 15 years, NS had a greater likelihood of sealant need (OR = 6.82, 95% CI = 1.60, 29.08). Caries-free status was associated with subsequent sealant receipt. Prior sealant need caused variability in dentists' decisions, depending on the child's age and past caries experience. Sealants were used infrequently by most providers and for a minority of patients. These findings are important for the Medicaid program and for future non-randomized studies of sealant effectiveness. 相似文献
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85.
This study investigated the impact of thermoplastic extrusion on the nutritive quality of bovine rumen protein. Proximal composition, amino acid profile and in vivo true protein digestibility among rats were determined in raw (RBR) and extruded (EBR) rumen. Raw and extruded bovine rumen presented high percentages of protein (more than 95% on dry basis). Neither raw nor extruded proteins had any limiting amino acid, and the RBR and EBR amino acid scores were, respectively, 1.28 (leucine) and 1.25 (methionine plus cystine). Extrusion reduced significantly true protein digestibility from 97.7% to 93.1% (p < 0.001), but protein digestibility-corrected amino acid scores for both proteins (RBR and EBR) were 100%. Animal growth presented comparable profiles using raw and extruded rumen. In conclusion, thermoplastic extrusion did not affect the protein quality of bovine rumen, and this does not hinder the use of this material as a food ingredient. 相似文献