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ABSTRACT Fiscal devolution fiom federal to state jurisdictions gives states more authority but also more responsibility for redistributing and stabilizing income. Both the revenue and expenditure sides of a state's budget are affected. This paper describes a social accounting matrix approach to documenting multi-regional, multi-jurisdiction fiscal accounts, called a fiscal SAM. Two of the many potential uses of a fiscal SAM are demonstrated. First, a fiscal SAM of rural, urban, and metro areas of Iowa is used directly to describe and compare the benchmark net fiscal situations of interdependent regions. Second, it is used to analyze the impacts of an economic downturn under a block-grant welfare system. Substate regions are relatively more specialized than state or national economies. Thus, for example, shocks to agriculture will directly affect agriculture-dependent counties more than other types of counties. Substate regions are also more interdependent than states, as well as more open than the nation as a whole. This means that indirect and spatial spillover effects of fiscal and other exogenous changes can be surprisingly large between counties. Here, analysis of fhe multipliers highlights the relative intensities of within and across-region effects of changes in the form of intergovernmental transfers. The multiplier simulation estimates the relative impacts and spillover effects of economic shocks under the new regime.  相似文献   
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Abstract. A single step procedure for purification of B-haemolysin from Aeromonas hydrophila is described which recovered 94% of the haemolytic activity with a sixfold increase in specific activity. Toxicity of haemolysin in 0-group channel catfish was 0–6 mg of purified protein per gram offish. Of six strains of A. hydrophila evaluated for differential toxin production and virulence in 0-group channel catfish, three B-haemolysin-deficient strains were virulent while three B-haemolysin-producing strains were avirulent.  相似文献   
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Magnetic resonance (MR) imaging is important in diagnosing musculoskeletal injuries in horses. However, there is still much to learn regarding the significance of lesions identified in equine MR images. Of particular importance is the clinical significance of signal change as a function of pulse sequence. We hypothesized that a resolution of tendon, ligament, and bone marrow lesions on short‐tau inversion recovery (STIR) images would be associated with a return to soundness, and that a persistence of tendon and ligament lesions on only T1‐weighted (T1w) gradient recalled echo (GRE) images would not be associated with persistent lameness. The medical records and MR images of 27 horses that had a hyperintense lesion in initial STIR MR images followed by a subsequent follow‐up MR imaging examination were reviewed. Horses whose tendon or ligament lesions had resolved on STIR images at the time of the recheck examination were significantly more likely to be sound than horses whose lesions persisted on STIR images (P=0.039). This association did not exist in horses with bone marrow lesions (P=1.00). Horses whose tendon or ligament lesions persisted only on T1w GRE images were no more likely to be sound than horses whose lesion persisted on at least one other sequence type (P=0.26). However, the low number of horses included in this analysis may have precluded identification of a significant difference in lameness status. Tendon or ligament lesions visualized on STIR images may represent active lesions that may contribute to lameness in the horse.  相似文献   
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The results of observation for three seasons in oilseed rape crops of the production and release of ascopores of Pyrenopeziza brassicae , the cause of light leaf spot disease of brassicas, are presented. Large apothecia (1–2 mm in diameter) take at least 3 weeks to develop on leaf petioles after infected leaves die, but small apothecia (50–200 um) may form on leaf lamellae after about 15 days. Apothecia were found on all 12 oilseed rape varieties examined. Spore trapping experiments in infected crops show that ascospore release is associated with rain, but most ascospores are released after rainfall when the crop debris bearing apothecia are wet. Ascospores can be released for up to 5 days after rain. Laboratory measurements show that apothecia can continue to release ascospores for up to 3 weeks even when they are subjected to wet and dry cycles. The consequences of the widespread occurrence of the sexual stage of P. brassicae are discussed and possible cycles of disease and spore production in oilseed crops are suggested.  相似文献   
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The VetMousetrap?, a novel device that allows computed tomography (CT) of awake cats and provides a clinically supportive environment, is described. Ten normal cats were used to test the device for ambient internal oxygen, carbon dioxide levels, and temperature. Twenty‐two awake normal cats were imaged using a 16‐multi‐slice helical CT unit to evaluate dose‐equivalent protocols. Two different X‐ray tube potentials (kV), 80 and 120, and two different helical pitches, 0.562 and 1.75, were evaluated. The signal intensity of the pulmonary parenchyma (SIlung), signal intensity of background (SIbackgr), contrast, noise, signal‐to‐noise ratio (SNR), and contrast‐to‐noise ratio (CNR) were calculated. Three evaluators ranked the images for sharpness of liver margins, motion, helical, and windmill artifacts. CT was successfully completed in 20 of 22 cats. No artifacts directly related to the device were detected. Overall, 75 of 80 (94%) examinations were judged to have absent or minimal motion artifact. A statistically significant difference was found for SNR (P=0.001) and CNR (P=0.001) between all protocols. The higher pitch protocols had significantly lower noise and higher SNR and CNR, lower motion artifact but greater helical artifacts. A protocol using 80 kV, 130 mA, 0.5 s, and 0.562 pitch with 1.25 mm slice thickness, and 0.625 mm slice reconstruction interval is recommended. The VetMousetrap? appears to provide the opportunity for diagnostic CT imaging of the thorax of awake cats.  相似文献   
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