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Annual Probability (annual + probability)
Selected AbstractsChanging Patterns in Medication Use with Increasing Probability of Death for Older Medicare BeneficiariesJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 8 2010Thomas Shaffer MHS OBJECTIVES: To determine whether use of symptom relief drugs (e.g., antidepressants, anxiolytics, opioid analgesics, sleep aids) rises and use of two commonly prescribed classes of chronic medications (statins and osteoporosis drugs) falls with greater probability of death for older Medicare beneficiaries. DESIGN: Pooled cross-sectional study. SETTING: Noninstitutionalized older Medicare population in 2000 to 2005. PARTICIPANTS: Community-dwelling Medicare beneficiaries aged 65 and older (N=20,233). MEASUREMENTS: Use of medications measured according to dichotomous flags; intensity of use by annual medication fills. Annual probability of death modeled using logistic regression and stratified into seven groups with predicted probabilities of death that range from less than 5% to greater than 50%. Prevalence of use and intensity (mean prescription fills per month) were computed for each class of medication. RESULTS: For symptom relief medications, there is relatively constant use with increasing probability of death, along with greater intensity of use. For the two chronic medications, there was a monotonic decrease in use but at a relatively constant intensity. Decline in statin use ranged from 34.4% in the lowest mortality stratum to 17.6% for those in the highest (P<.001). Use of osteoporosis drugs fell from 10.4% to 6.6% over the same range (P<.001). CONCLUSION: Greater intensity of use of symptom relief medications with increasing probability of death is consistent with hypothesized use. The different profile for chronic medications suggests that the time to benefit is being considered regarding therapy initiation, which results in lower use. [source] Probabilistic evaluation of seismic performance of 3-story 3D one- and two-way steel moment-frame structuresEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 5 2008Hiroyuki Tagawa Abstract This paper presents the results of a probabilistic evaluation of the seismic performance of 3D steel moment-frame structures. Two types of framing system are considered: one-way frames typical of construction in the United States and two-way frames typical of construction in Japan. For each framing system, four types of beam,column connections are considered: pre-Northridge welded-flange bolted-web, post-Northridge welded-flange welded-web, reduced-beam-section, and bolted-flange-plate connections. A suite of earthquake ground motions is used to compute the annual probability of exceedence (APE) for a series of drift demand levels and for member plastic-rotation capacity. Results are compared for the different framing systems and connection details. It is found that the two-way frames, which have a larger initial stiffness and strength than the one-way frames for the same beam and column volumes, have a smaller APE for small drift demands for which members exhibit no or minimal yielding, but have a larger APE for large drift demands for which members exhibit large plastic rotations. However, the one-way frames, which typically comprise a few seismic frames with large-sized members that have relatively small rotation capacities, may have a larger APE for member failure. The probabilistic approach presented in this study may be used to determine the most appropriate frame configuration to meet an owner's performance objectives. Copyright © 2008 John Wiley & Sons, Ltd. [source] ENVIRONMENTAL CONDITIONS AFFECT THE MAGNITUDE OF INBREEDING DEPRESSION IN SURVIVAL OF DARWIN'S FINCHESEVOLUTION, Issue 6 2002Lukas F. Keller Abstract Understanding the fitness consequences of inbreeding (inbreeding depression) is of importance to evolutionary and conservation biology. There is ample evidence for inbreeding depression in captivity, and data from wild populations are accumulating. However, we still lack a good quantitative understanding of inbreeding depression and what influences its magnitude in natural populations. Specifically, the relationship between the magnitude of inbreeding depression and environmental severity is unclear. We quantified inbreeding depression in survival and reproduction in populations of cactus finches (Geospiza scandens) and medium ground finches (Geospiza fortis) living on Isla Daphne Major in the Galapagos Archipelago. Our analyses showed that inbreeding strongly reduced the recruitment probability (probability of breeding given that an adult is alive) in both species. Additionally, in G. scandens, first-year survival of an offspring withf= 0.25 was reduced by 21% and adults withf= 0.25 experienced a 45% reduction in their annual probability of survival. The magnitude of inbreeding depression in both adult and juvenile survival of this species was strongly modified by two environmental conditions, food availability and number of competitors. In juveniles, inbreeding depression was only present in years with low food availability, and in adults inbreeding depression was five times more severe in years with low food availability and large population sizes. The combination of relatively severe inbreeding depression in survival and the reduced recruitment probability led to the fact that very few inbred G. scandens ever succeeded in breeding. Other than recruitment probability, no other trait showed evidence of inbreeding depression in G. fortis, probably for two reasons: a relatively high rate of extrapair paternity (20%), which may lead to an underestimate of the apparent inbreeding depression, and low sample sizes of highly inbred G. fortis, which leads to low statistical power. Using data from juvenile survival, we estimated the number of lethal equivalents carried by G. scandens, G. fortis, and another congener, G. magnirostris. These results suggest that substantial inbreeding depression can exist in insular populations of birds, and that the magnitude of the inbreeding depression is a function of environmental conditions. [source] Cohort variation in offspring growth and survival: prenatal and postnatal factors in a late-maturing viviparous snakeJOURNAL OF ANIMAL ECOLOGY, Issue 3 2010Jean-Pierre Baron Summary 1. Recruitment to adulthood plays an important role in the population dynamics of late-maturing organisms as it is usually variable. Compared to birds and mammals, few studies assessing the contributions to this variation of environmental factors, offspring traits and maternal traits have been carried out for late-maturing snakes. 2. Cohort variation in recruitment through offspring growth and survival in the meadow viper (Vipera ursinii ursinii) was evaluated from 13 years of mark,recapture data collected at Mont Ventoux, France. In this species, females are mature at the age of 4,6 years and adult survival and fecundity rates are high and constant over time. 3. Offspring were difficult to catch during the first 3 years of their lives, but their mean annual probability of survival was reasonably high (0·48 ± 0·11 SE). Mass and body condition at birth (mass residuals) varied significantly between years, decreased with litter size, and increased with maternal length. 4. Cohorts of offspring in better condition at birth grew faster, but offspring growth was not affected by sex, habitat or maternal traits. 5. Survival varied considerably between birth cohorts, some cohorts having a high-survival rate and others having essentially no survivors. No difference in mass or body condition at birth was found between cohorts with ,no survival' and ,good survival'. However, offspring survival in cohorts with good survival was positively correlated with mass at birth and negatively correlated with body condition at birth. 6. Thus, variation in offspring performance was influenced by direct environmental effects on survival and indirect environmental effects on growth, mediated by body condition at birth. Effects of maternal traits were entirely channelled through offspring traits. [source] | ||||||||||