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21.

Background  

Alignment of RNA secondary structures is important in studying functional RNA motifs. In recent years, much progress has been made in RNA motif finding and structure alignment. However, existing tools either require a large number of prealigned structures or suffer from high time complexities. This makes it difficult for the tools to process RNAs whose prealigned structures are unavailable or process very large RNA structure databases.  相似文献   
22.

Introduction

The prevalence of diabetes is increasing worldwide. The objective of this study is to estimate the prevalence of self-reported diabetes in Brazilian adults and to describe its population correlates as well as the clinical characteristics of the reported cases.

Methods

We analyzed basic and supplementary data of 54.144 subjects participating in VIGITEL 2011 (Surveillance System for Risk and Protective Factors for Chronic Diseases), a telephone survey based on a probabilistic sample of subjects ≥18 years old residing in Brazilian state capitals and the Federal District. Estimates reported are weighted so as to represent the surveyed population.

Results

The prevalence of self-reported diabetes was 6.3% (95% CI 5.9–6.7), increasing markedly with age and nutritional status, and decreasing with level of education. Prevalence was higher among those self-declaring their race/color as black. Most cases (90%) reported the diagnosis being made at 35 years or older. The vast majority (99.8%) of self-reported cases informed having previously performed at least one glucose test, and 76% of those not reporting diabetes also informed having previously performed glucose testing. Most cases (92.6%) reported following some form of diabetes treatment, 79% taking medication.

Conclusion

The estimated prevalence of known diabetes found, 6.3%, is consistent with estimates given by international summaries. The additional data collected in VIGITEL 2011 regarding previous glucose testing and current treatment support the use of telephone-based information to monitor the prevalence of known diabetes in Brazilian capitals.  相似文献   
23.
We investigated the effects on the reservoir food web of a new temperature control device (TCD) on the dam at Shasta Lake, California. We followed a linked modeling approach that used a specialized reservoir water quality model to forecast operation-induced changes in phytoplankton production. A food web–energy transfer model was also applied to propagate predicted changes in phytoplankton up through the food web to the predators and sport fishes of interest. The food web–energy transfer model employed a 10% trophic transfer efficiency through a food web that was mapped using carbon and nitrogen stable isotope analysis. Stable isotope analysis provided an efficient and comprehensive means of estimating the structure of the reservoir's food web with minimal sampling and background data. We used an optimization procedure to estimate the diet proportions of all food web components simultaneously from their isotopic signatures. Some consumers were estimated to be much more sensitive than others to perturbations to phytoplankton supply. The linked modeling approach demonstrated that interdisciplinary efforts enhance the value of information obtained from studies of managed ecosystems. The approach exploited the strengths of engineering and ecological modeling methods to address concerns that neither of the models could have addressed alone: (a) the water quality model could not have addressed quantitatively the possible impacts to fish, and (b) the food web model could not have examined how phytoplankton availability might change due to reservoir operations. Received 22 February 2000; accepted 6 October 2000.  相似文献   
24.
Olfactory memory: the long and short of it   总被引:2,自引:2,他引:0  
White  TL 《Chemical senses》1998,23(4):433-441
It has been proposed that memory for odors does not have a short-term (or working) memory system. The distinction between short- and long- term memory in other sensory modalities has been generally supported by three main lines of evidence: capacity differences between the proposed systems, evidence of differential coding, and differential memory losses in neuropsychological patients. The present paper examines these issues in an effort to establish a similar distinction for the memory of olfactory stimuli. Each of these lines of evidence is examined in relation to the literature on olfactory memory. Based on this examination, it seems that there is at least preliminary support from each of these lines of evidence to advocate a distinction between a long- and short-term memory for olfactory stimuli. Emphasis is placed upon the qualitative similarity of olfactory memory to other memory systems. This similarity is further highlighted through an examination of the literature pertinent to serial position effects in memory for olfactory stimuli.   相似文献   
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