A limited reproducibility has been ascribed to 24-h ambulatory blood pressure monitoring, especially in relation to the dipper and nondipper phenomena. This study examined the reproducibility of 24-h ambulatory blood pressure monitoring in three recordings of pressure at intervals of 8-15 days in 101 study participants (73% treated hypertensive patients) residing in the city of Recife, Pernambuco, Brazil. SpaceLabs 90207 monitors were used, and the minimum number of valid measurements was 80. No significant differences were found between the mean systolic and diastolic pressures, between the second and third recordings when the normotensive and hypertensive patients were assessed jointly (P=0.44). Likewise, no significant differences were present when the normotensive patients were analyzed separately (P=0.96). In the hypertensive group, a significant difference existed between only the first and second ambulatory blood pressure readings (135.1 vs. 132.9 mmHg, respectively; P=0.0005). Regarding declines in pressure during sleep, no significant differences occurred when continuous percentage values were considered (P=0.27). The values obtained from 24-h ambulatory blood pressure monitoring are reproducible when tested at intervals of 8-15 days. Small differences, when significantly present, always involved the first ambulatory blood pressure monitoring. The reproducibility of the dipper and nondipper patterns is of greater complexity because it considers cutoff points rather than continuous ones to characterize these states.

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The uncertainty may be classified into two major groups, "objective uncertainty" and "subjective uncertainty". The subject of this article is the decision making under subjective uncertainty. One of the formal models that deal with subjective uncertainty, the Mathematical Theory of Evidence, is extended and its counter-intuitive behavior corrected, allowing the making of correct decisions in a wider range of situations than the original model.The Mathematical Theory of Evidence, or Dempster-Shafer Theory, is a popular formalism to model someone's degrees of belieL This theory provides a method for combining evidence from different sources without prior knowledge of their distributions, it is also possible to assign probability values to sets of possibilities rather than to single events only, and it is unnecessary to divide all the probability values among the events, once the remaining probability should be assigned to the environment and not to the remaining events, thus modeling more naturally certain classes of problems. However, it has some pitfalls caused by the non-natural embodiment of the uncertainty in the results.In this paper we present a method of automatic embodiment of the uncertainty that overcomes the aforementioned pitfalls, allowing the combination of evidence with higher degrees of conflict, and avoiding the excessive tendency toward the common possibility of otherwise disjoint hypotheses. This is accomplished by means of a new rule of combination of bodies of evidence that embodies in the numeric results the unknown belief and conflict among the evidence, naturally modeling the epistemic reasoning.

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This study presents one approach to investing in the financial markets using a decision theory point of view, where the main decision is to choose an investment portfolio, based on economic indexes, in order to predict future investments based on historical data, which minimizes the risk involved. The decision model is based on Decision Theory and Bayesian Analysis and the application uses Brazilian financial market data from

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An optimal control approach is used to analyze the tradeoff between the use of water resources for electricity generation versus other economic uses (irrigation, industry, etc.). For that purpose, a dynamic model is presented which establishes relationships between economic growth, water resources management, and energy policy in the context of the aforementioned tradeoff, in an economy whose energy matrix is heavily dependent upon hydroelectric power. Among other results, the analysis establishes that in the market, the price of water for non-energy uses should be twice the price of the energy goods, indicating the necessity of substituting other sources of energy for hydroelectric power.

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