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Sample records for adult survival probability

  1. Estimates of annual survival probabilities for adult Florida manatees (Trichechus manatus latirostris)

    USGS Publications Warehouse

    Langtimm, C.A.; O'Shea, T.J.; Pradel, R.; Beck, C.A.

    1998-01-01

    The population dynamics of large, long-lived mammals are particularly sensitive to changes in adult survival. Understanding factors affecting survival patterns is therefore critical for developing and testing theories of population dynamics and for developing management strategies aimed at preventing declines or extinction in such taxa. Few studies have used modern analytical approaches for analyzing variation and testing hypotheses about survival probabilities in large mammals. This paper reports a detailed analysis of annual adult survival in the Florida manatee (Trichechus manatus latirostris), an endangered marine mammal, based on a mark-recapture approach. Natural and boat-inflicted scars distinctively 'marked' individual manatees that were cataloged in a computer-based photographic system. Photo-documented resightings provided 'recaptures.' Using open population models, annual adult-survival probabilities were estimated for manatees observed in winter in three areas of Florida: Blue Spring, Crystal River, and the Atlantic coast. After using goodness-of-fit tests in Program RELEASE to search for violations of the assumptions of mark-recapture analysis, survival and sighting probabilities were modeled under several different biological hypotheses with Program SURGE. Estimates of mean annual probability of sighting varied from 0.948 for Blue Spring to 0.737 for Crystal River and 0.507 for the Atlantic coast. At Crystal River and Blue Spring, annual survival probabilities were best estimated as constant over the study period at 0.96 (95% CI = 0.951-0.975 and 0.900-0.985, respectively). On the Atlantic coast, where manatees are impacted more by human activities, annual survival probabilities had a significantly lower mean estimate of 0.91 (95% CI = 0.887-0.926) and varied unpredictably over the study period. For each study area, survival did not differ between sexes and was independent of relative adult age. The high constant adult-survival probabilities estimated

  2. Lower survival probabilities for adult Florida manatees in years with intense coastal storms

    USGS Publications Warehouse

    Langtimm, C.A.; Beck, C.A.

    2003-01-01

    The endangered Florida manatee (Trichechus manatus latirostris) inhabits the subtropical waters of the southeastern United States, where hurricanes are a regular occurrence. Using mark-resighting statistical models, we analyzed 19 years of photo-identification data and detected significant annual variation in adult survival for a subpopulation in northwest Florida where human impact is low. That variation coincided with years when intense hurricanes (Category 3 or greater on the Saffir-Simpson Hurricane Scale) and a major winter storm occurred in the northern Gulf of Mexico. Mean survival probability during years with no or low intensity storms was 0.972 (approximate 95% confidence interval = 0.961-0.980) but dropped to 0.936 (0.864-0.971) in 1985 with Hurricanes Elena, Kate, and Juan; to 0.909 (0.837-0.951) in 1993 with the March "Storm of the Century"; and to 0.817 (0.735-0.878) in 1995 with Hurricanes Opal, Erin, and Allison. These drops in survival probability were not catastrophic in magnitude and were detected because of the use of state-of-the-art statistical techniques and the quality of the data. Because individuals of this small population range extensively along the north Gulf coast of Florida, it was possible to resolve storm effects on a regional scale rather than the site-specific local scale common to studies of more sedentary species. This is the first empirical evidence in support of storm effects on manatee survival and suggests a cause-effect relationship. The decreases in survival could be due to direct mortality, indirect mortality, and/or emigration from the region as a consequence of storms. Future impacts to the population by a single catastrophic hurricane, or series of smaller hurricanes, could increase the probability of extinction. With the advent in 1995 of a new 25- to 50-yr cycle of greater hurricane activity, and longer term change possible with global climate change, it becomes all the more important to reduce mortality and injury

  3. Survival probability in patients with liver trauma.

    PubMed

    Buci, Skender; Kukeli, Agim

    2016-08-01

    Purpose - The purpose of this paper is to assess the survival probability among patients with liver trauma injury using the anatomical and psychological scores of conditions, characteristics and treatment modes. Design/methodology/approach - A logistic model is used to estimate 173 patients' survival probability. Data are taken from patient records. Only emergency room patients admitted to University Hospital of Trauma (former Military Hospital) in Tirana are included. Data are recorded anonymously, preserving the patients' privacy. Findings - When correctly predicted, the logistic models show that survival probability varies from 70.5 percent up to 95.4 percent. The degree of trauma injury, trauma with liver and other organs, total days the patient was hospitalized, and treatment method (conservative vs intervention) are statistically important in explaining survival probability. Practical implications - The study gives patients, their relatives and physicians ample and sound information they can use to predict survival chances, the best treatment and resource management. Originality/value - This study, which has not been done previously, explores survival probability, success probability for conservative and non-conservative treatment, and success probability for single vs multiple injuries from liver trauma. PMID:27477933

  4. Robust satisficing and the probability of survival

    NASA Astrophysics Data System (ADS)

    Ben-Haim, Yakov

    2014-01-01

    Concepts of robustness are sometimes employed when decisions under uncertainty are made without probabilistic information. We present a theorem that establishes necessary and sufficient conditions for non-probabilistic robustness to be equivalent to the probability of satisfying the specified outcome requirements. When this holds, probability is enhanced (or maximised) by enhancing (or maximising) robustness. Two further theorems establish important special cases. These theorems have implications for success or survival under uncertainty. Applications to foraging and finance are discussed.

  5. Bacteria survival probability in bactericidal filter paper.

    PubMed

    Mansur-Azzam, Nura; Hosseinidoust, Zeinab; Woo, Su Gyeong; Vyhnalkova, Renata; Eisenberg, Adi; van de Ven, Theo G M

    2014-05-01

    Bactericidal filter papers offer the simplicity of gravity filtration to simultaneously eradicate microbial contaminants and particulates. We previously detailed the development of biocidal block copolymer micelles that could be immobilized on a filter paper to actively eradicate bacteria. Despite the many advantages offered by this system, its widespread use is hindered by its unknown mechanism of action which can result in non-reproducible outcomes. In this work, we sought to investigate the mechanism by which a certain percentage of Escherichia coli cells survived when passing through the bactericidal filter paper. Through the process of elimination, the possibility that the bacterial survival probability was controlled by the initial bacterial load or the existence of resistant sub-populations of E. coli was dismissed. It was observed that increasing the thickness or the number of layers of the filter significantly decreased bacterial survival probability for the biocidal filter paper but did not affect the efficiency of the blank filter paper (no biocide). The survival probability of bacteria passing through the antibacterial filter paper appeared to depend strongly on the number of collision between each bacterium and the biocide-loaded micelles. It was thus hypothesized that during each collision a certain number of biocide molecules were directly transferred from the hydrophobic core of the micelle to the bacterial lipid bilayer membrane. Therefore, each bacterium must encounter a certain number of collisions to take up enough biocide to kill the cell and cells that do not undergo the threshold number of collisions are expected to survive. PMID:24681395

  6. Adult Survival Skills Assessment.

    ERIC Educational Resources Information Center

    Walsko, Gregory M.

    The purpose of this instrument is to supplement data from the Adult Basic Learning Examination in assessing the functional level of adults in daily situations. It may also be used as a teaching tool for adults requesting tutoring in specific concepts and skills presented in the instrument. This instrument is an informal assessment instrument and…

  7. Conditional Probability of Survival in Patients With Newly Diagnosed Glioblastoma

    PubMed Central

    Polley, Mei-Yin C.; Lamborn, Kathleen R.; Chang, Susan M.; Butowski, Nicholas; Clarke, Jennifer L.; Prados, Michael

    2011-01-01

    Purpose The disease outcome for patients with cancer is typically described in terms of estimated survival from diagnosis. Conditional probability offers more relevant information regarding survival for patients once they have survived for some time. We report conditional survival probabilities on the basis of 498 patients with glioblastoma multiforme receiving radiation and chemotherapy. For 1-year survivors, we evaluated variables that may inform subsequent survival. Motivated by the trend in data, we also evaluated the assumption of constant hazard. Patients and Methods Patients enrolled onto seven phase II protocols between 1975 and 2007 were included. Conditional survival probabilities and 95% CIs were calculated. The Cox proportional hazards model was used to evaluate prognostic values of age, Karnofsky performance score (KPS), and prior progression 1-year post diagnosis. To assess the constant hazard assumption, we used a likelihood-ratio test to compare the Weibull and exponential distributions. Results The probabilities of surviving an additional year given survival to 1, 2, 3, and 4 years were 35%, 49%, 69%, and 93%, respectively. For patients who survived for 1 year, lower KPS and progression were significantly predictive of shorter survival (both P < .001), but age was not (hazard ratio, 1.22 for a 10-year increase; P = .25). The Weibull distribution fits the data significantly better than exponential (P = .02), suggesting nonconstant hazard. Conclusion Conditional probabilities provide encouraging information regarding life expectancy to survivors of glioblastoma multiforme. Our data also showed that the constant hazard assumption may be violated in modern brain tumor trials. For single-arm trials, we advise using individual patient data from historical data sets for efficacy comparisons. PMID:21969507

  8. Differential Survival in Europe and the United States: Estimates Based on Subjective Probabilities of Survival

    PubMed Central

    Delavande, Adeline; Rohwedder, Susann

    2013-01-01

    Cross-country comparisons of differential survival by socioeconomic status (SES) are useful in many domains. Yet, to date, such studies have been rare. Reliably estimating differential survival in a single country has been challenging because it requires rich panel data with a large sample size. Cross-country estimates have proven even more difficult because the measures of SES need to be comparable internationally. We present an alternative method for acquiring information on differential survival by SES. Rather than using observations of actual survival, we relate individuals’ subjective probabilities of survival to SES variables in cross section. To show that subjective survival probabilities are informative proxies for actual survival when estimating differential survival, we compare estimates of differential survival based on actual survival with estimates based on subjective probabilities of survival for the same sample. The results are remarkably similar. We then use this approach to compare differential survival by SES for 10 European countries and the United States. Wealthier people have higher survival probabilities than those who are less wealthy, but the strength of the association differs across countries. Nations with a smaller gradient appear to be Belgium, France, and Italy, while the United States, England, and Sweden appear to have a larger gradient. PMID:22042664

  9. Estimating survival rates from banding of adult and juvenile birds

    USGS Publications Warehouse

    Johnson, D.H.

    1974-01-01

    The restrictive assumptions required by most available methods for estimating survival probabilities render them unsuitable for analyzing real banding data. A model is proposed which allows survival rates and recovery rates to vary with the calendar year, and also allows juveniles to have rates different from adults. In addition to survival rates and recovery rates, the differential vulnerability factors of juveniles relative to adults are estimated. Minimum values of the variances of the estimators are also given. The new procedure is applied to sets of duck and goose data in which reasonably large numbers of adult and juvenile birds were banded. The results are shown to be generally comparable to those procured by other methods, but, in addition, insight into the extent of annual variation is gained. Combining data from adults and juveniles also increases the effective sample size, since the juveniles are assumed to enter the adult age class after surviving their initial year.

  10. Estimating Second Order Probability Beliefs from Subjective Survival Data

    PubMed Central

    Hudomiet, Péter; Willis, Robert J.

    2013-01-01

    Based on subjective survival probability questions in the Health and Retirement Study (HRS), we use an econometric model to estimate the determinants of individual-level uncertainty about personal longevity. This model is built around the modal response hypothesis (MRH), a mathematical expression of the idea that survey responses of 0%, 50%, or 100% to probability questions indicate a high level of uncertainty about the relevant probability. We show that subjective survival expectations in 2002 line up very well with realized mortality of the HRS respondents between 2002 and 2010. We show that the MRH model performs better than typically used models in the literature of subjective probabilities. Our model gives more accurate estimates of low probability events and it is able to predict the unusually high fraction of focal 0%, 50%, and 100% answers observed in many data sets on subjective probabilities. We show that subjects place too much weight on parents’ age at death when forming expectations about their own longevity, whereas other covariates such as demographics, cognition, personality, subjective health, and health behavior are under weighted. We also find that less educated people, smokers, and women have less certain beliefs, and recent health shocks increase uncertainty about survival, too. PMID:24403866

  11. Finite-size scaling of survival probability in branching processes

    NASA Astrophysics Data System (ADS)

    Garcia-Millan, Rosalba; Font-Clos, Francesc; Corral, Álvaro

    2015-04-01

    Branching processes pervade many models in statistical physics. We investigate the survival probability of a Galton-Watson branching process after a finite number of generations. We derive analytically the existence of finite-size scaling for the survival probability as a function of the control parameter and the maximum number of generations, obtaining the critical exponents as well as the exact scaling function, which is G (y ) =2 y ey /(ey-1 ) , with y the rescaled distance to the critical point. Our findings are valid for any branching process of the Galton-Watson type, independently of the distribution of the number of offspring, provided its variance is finite. This proves the universal behavior of the finite-size effects in branching processes, including the universality of the metric factors. The direct relation to mean-field percolation is also discussed.

  12. Electron-neutrino survival probability from solar-neutrino data

    NASA Astrophysics Data System (ADS)

    Berezinsky, V.; Lissia, M.

    2001-11-01

    With SNO data [SNO Collaboration, nucl-ex/0106015] on electron-neutrino flux from the sun, it is possible to derive the νe survival probability Pee(E) from existing experimental data of Super-Kamiokande, gallium experiments and Homestake. The combined data of SNO and Super-Kamiokande provide boron νe flux and the total flux of all active boron neutrinos, giving thus Pee(E) for boron neutrinos. The Homestake detector, after subtraction of the signal from boron neutrinos, gives the flux of Be/+CNO neutrinos, and Pee for the corresponding energy interval, if the produced flux is taken from the Standard Solar Model (SSM). Gallium detectors, GALLEX, SAGE and GNO, detect additionally /pp-neutrinos. The /pp flux can be calculated subtracting from the gallium signal the rate due to boron, beryllium and CNO neutrinos. The ratio of the measured /pp-neutrino flux to that predicted by the SSM gives the survival probability for /pp-neutrinos. Comparison with theoretical survival probabilities shows that the best (among known models) fit is given by LMA and LOW solutions.

  13. Declining survival probability threatens the North Atlantic right whale.

    PubMed

    Caswell, H; Fujiwara, M; Brault, S

    1999-03-16

    The North Atlantic northern right whale (Eubalaena glacialis) is considered the most endangered large whale species. Its population has recovered only slowly since the cessation of commercial whaling and numbers about 300 individuals. We applied mark-recapture statistics to a catalog of photographically identified individuals to obtain the first statistically rigorous estimates of survival probability for this population. Crude survival decreased from about 0.99 per year in 1980 to about 0.94 in 1994. We combined this survival trend with a reported decrease in reproductive rate into a branching process model to compute population growth rate and extinction probability. Population growth rate declined from about 1. 053 in 1980 to about 0.976 in 1994. Under current conditions the population is doomed to extinction; an upper bound on the expected time to extinction is 191 years. The most effective way to improve the prospects of the population is to reduce mortality. The right whale is at risk from entanglement in fishing gear and from collisions with ships. Reducing this human-caused mortality is essential to the viability of this population. PMID:10077680

  14. Measurement of the survival probabilities for hot fusion reactions.

    PubMed

    Yanez, R; Loveland, W; Yao, L; Barrett, J S; Zhu, S; Back, B B; Khoo, T L; Alcorta, M; Albers, M

    2014-04-18

    We have studied the fission-neutron emission competition in highly excited (274)Hs (Z=108) (where the fission barrier is due to shell effects) formed by a hot fusion reaction. Matching cross bombardments ((26)Mg+(248)Cm and (25)Mg+(248)Cm) were used to identify the properties of first chance fission of (274)Hs. A Harding-Farley analysis of the fission neutrons emitted in the (25)Mg,26+(248)Cm was performed to identify the prescission and postscission components of the neutron multiplicities in each system. (Γn/Γt) for the first chance fission of (274)Hs (E*=63  MeV) is 0.89±0.13; i.e., ∼90% of the highly excited nuclei survive. The high value of that survival probability is due to dissipative effects during deexcitation. A proper description of the survival probabilities of excited superheavy nuclei formed in hot fusion reactions requires consideration of both dynamic and static (shell-related) effects. PMID:24785034

  15. Seasonal survival probabilities suggest low migration mortality in migrating bats.

    PubMed

    Giavi, Simone; Moretti, Marco; Bontadina, Fabio; Zambelli, Nicola; Schaub, Michael

    2014-01-01

    Migration is adaptive if survival benefits are larger than costs of residency. Many aspects of bat migration ecology such as migratory costs, stopover site use and fidelity are largely unknown. Since many migrating bats are endangered, such information is urgently needed to promote conservation. We selected the migrating Leisler's bat (Nyctalus leisleri) as model species and collected capture-recapture data in southern Switzerland year round during 6 years. We estimated seasonal survival and site fidelity with Cormack-Jolly-Seber models that accounted for the presence of transients fitted with Bayesian methods and assessed differences between sexes and seasons. Activity peaked in autumn and spring, whereas very few individuals were caught during summer. We hypothesize that the study site is a migratory stopover site used during fall and spring migration for most individuals, but there is also evidence for wintering. Additionally, we found strong clues for mating during fall. Summer survival that included two major migratory journeys was identical to winter survival in males and slightly higher in females, suggesting that the migratory journeys did not bear significant costs in terms of survival. Transience probability was in both seasons higher in males than in females. Our results suggest that, similarly to birds, Leisler's bat also use stopover sites during migration with high site fidelity. In contrast to most birds, the stopover site was also used for mating and migratory costs in terms of survival seemed to be low. Transients' analyses highlighted strong individual variation in site use which makes particularly challenging the study and modelling of their populations as well as their conservation. PMID:24454906

  16. Seasonal Survival Probabilities Suggest Low Migration Mortality in Migrating Bats

    PubMed Central

    Giavi, Simone; Moretti, Marco; Bontadina, Fabio; Zambelli, Nicola; Schaub, Michael

    2014-01-01

    Migration is adaptive if survival benefits are larger than costs of residency. Many aspects of bat migration ecology such as migratory costs, stopover site use and fidelity are largely unknown. Since many migrating bats are endangered, such information is urgently needed to promote conservation. We selected the migrating Leisler's bat (Nyctalus leisleri) as model species and collected capture-recapture data in southern Switzerland year round during 6 years. We estimated seasonal survival and site fidelity with Cormack-Jolly-Seber models that accounted for the presence of transients fitted with Bayesian methods and assessed differences between sexes and seasons. Activity peaked in autumn and spring, whereas very few individuals were caught during summer. We hypothesize that the study site is a migratory stopover site used during fall and spring migration for most individuals, but there is also evidence for wintering. Additionally, we found strong clues for mating during fall. Summer survival that included two major migratory journeys was identical to winter survival in males and slightly higher in females, suggesting that the migratory journeys did not bear significant costs in terms of survival. Transience probability was in both seasons higher in males than in females. Our results suggest that, similarly to birds, Leisler's bat also use stopover sites during migration with high site fidelity. In contrast to most birds, the stopover site was also used for mating and migratory costs in terms of survival seemed to be low. Transients' analyses highlighted strong individual variation in site use which makes particularly challenging the study and modelling of their populations as well as their conservation. PMID:24454906

  17. Probability of moraine survival in a succession of glacial advances.

    USGS Publications Warehouse

    Gibbons, A.B.; Megeath, J.D.; Pierce, K.L.

    1984-01-01

    Emplacement of glacial moraines normally results in obliteration of older moraines deposited by less extensive glacial advances, a process we call 'obliterative overlap'. Assuming randomness and obliterative overlap, after 10 glacial episodes the most likely number of surviving moraines is only three. The record of the Pleistocene is in agreement with the probability analysis: the 10 glaciations during the past 0.9 Myr inferred from the deep-sea record resulted in moraine sequences in which only two or three different-aged moraine belts can generally be distinguished. -from Authors

  18. Annual survival rates of breeding adult roseate terns

    USGS Publications Warehouse

    Spendelow, J.A.; Nichols, J.D.

    1989-01-01

    Analyses of the capture-recapture data on 0 individual roseate terns (Sterna dougallii) trapped from 1978-1987 as breeding adults on nests on Falkner Island, Connecticut, estimate the average annual minimum adult survival rate to be 0.74-0.75. There was weak evidence of year-to-year variation in annual survival rates during the study period. The Jolly-Seber models used to estimate survival rates also generated estimates of population size and capture probabilities. To determine the relative importance of adult mortality and permanent emigration in contribuuting to the estimated annual loss of one-fourth of the breeding population will require further study of intercolony movemnet between all the major colony cities.

  19. Interactive effects of senescence and natural disturbance on the annual survival probabilities of snail kites

    USGS Publications Warehouse

    Reichert, Brian E.; Martin, J.; Kendall, William L.; Cattau, Christopher E.; Kitchens, Wiley M.

    2010-01-01

    Individuals in wild populations face risks associated with both intrinsic (i.e. aging) and external (i.e. environmental) sources of mortality. Condition-dependent mortality occurs when there is an interaction between such factors; however, few studies have clearly demonstrated condition-dependent mortality and some have even argued that condition-dependent mortality does not occur in wild avian populations. Using large sample sizes (2084 individuals, 3746 re-sights) of individual-based longitudinal data collected over a 33 year period (1976-2008) on multiple cohorts, we used a capture-mark-recapture framework to model age-dependent survival in the snail kite Rostrhamus sociabilis plumbeus population in Florida. Adding to the growing amount of evidence for actuarial senescence in wild populations, we found evidence of senescent declines in survival probabilities in adult kites. We also tested the hypothesis that older kites experienced condition-dependent mortality during a range-wide drought event (2000-2002). The results provide convincing evidence that the annual survival probability of senescent kites was disproportionately affected by the drought relative to the survival probability of prime-aged adults. To our knowledge, this is the first evidence of condition-dependent mortality to be demonstrated in a wild avian population, a finding which challenges recent conclusions drawn in the literature. Our study suggests that senescence and condition-dependent mortality can affect the demography of wild avian populations. Accounting for these sources of variation may be particularly important to appropriately compute estimates of population growth rate, and probabilities of quasi-extinctions.

  20. Basic & Survival Consumer Economics for Adult Refugees.

    ERIC Educational Resources Information Center

    Carlston, Peter G.

    Prepared to help teachers address the basic and survival level consumer needs of adult Vietnamese and Laotian refugees, this instructional guide consists of five units of instructional materials. Topics of the individual units are (1) how the monetary system works (cash, checks, postal money orders, banking); (2) the family consumer (personal and…

  1. Estimating survival and breeding probability for pond-breeding amphibians: a modified robust design

    USGS Publications Warehouse

    Bailey, L.L.; Kendall, W.L.; Church, D.R.; Wilbur, H.M.

    2004-01-01

    Many studies of pond-breeding amphibians involve sampling individuals during migration to and from breeding habitats. Interpreting population processes and dynamics from these studies is difficult because (1) only a proportion of the population is observable each season, while an unknown proportion remains unobservable (e.g., non-breeding adults) and (2) not all observable animals are captured. Imperfect capture probability can be easily accommodated in capture?recapture models, but temporary transitions between observable and unobservable states, often referred to as temporary emigration, is known to cause problems in both open- and closed-population models. We develop a multistate mark?recapture (MSMR) model, using an open-robust design that permits one entry and one exit from the study area per season. Our method extends previous temporary emigration models (MSMR with an unobservable state) in two ways. First, we relax the assumption of demographic closure (no mortality) between consecutive (secondary) samples, allowing estimation of within-pond survival. Also, we add the flexibility to express survival probability of unobservable individuals (e.g., ?non-breeders?) as a function of the survival probability of observable animals while in the same, terrestrial habitat. This allows for potentially different annual survival probabilities for observable and unobservable animals. We apply our model to a relictual population of eastern tiger salamanders (Ambystoma tigrinum tigrinum). Despite small sample sizes, demographic parameters were estimated with reasonable precision. We tested several a priori biological hypotheses and found evidence for seasonal differences in pond survival. Our methods could be applied to a variety of pond-breeding species and other taxa where individuals are captured entering or exiting a common area (e.g., spawning or roosting area, hibernacula).

  2. Survival probability for a diffusive process on a growing domain

    NASA Astrophysics Data System (ADS)

    Simpson, Matthew J.; Sharp, Jesse A.; Baker, Ruth E.

    2015-04-01

    We consider the motion of a diffusive population on a growing domain, 0 survival probability, S (t ) , and an accurate approximation for the long-time limit, S =limt→∞S (t ) . Unlike traditional analyses on a nongrowing domain, where S ≡0 , we show that domain growth leads to a very different situation where S can be positive. The theoretical tools developed and validated in this study allow us to distinguish between situations where the diffusive population reaches the moving boundary at x =L (t ) from other situations where the diffusive population never reaches the moving boundary at x =L (t ) . Making this distinction is relevant to certain applications in developmental biology, such as the development of the enteric nervous system (ENS). All theoretical predictions are verified by implementing a discrete stochastic model.

  3. Mean exit time and survival probability within the CTRW formalism

    NASA Astrophysics Data System (ADS)

    Montero, M.; Masoliver, J.

    2007-05-01

    An intense research on financial market microstructure is presently in progress. Continuous time random walks (CTRWs) are general models capable to capture the small-scale properties that high frequency data series show. The use of CTRW models in the analysis of financial problems is quite recent and their potentials have not been fully developed. Here we present two (closely related) applications of great interest in risk control. In the first place, we will review the problem of modelling the behaviour of the mean exit time (MET) of a process out of a given region of fixed size. The surveyed stochastic processes are the cumulative returns of asset prices. The link between the value of the MET and the timescale of the market fluctuations of a certain degree is crystal clear. In this sense, MET value may help, for instance, in deciding the optimal time horizon for the investment. The MET is, however, one among the statistics of a distribution of bigger interest: the survival probability (SP), the likelihood that after some lapse of time a process remains inside the given region without having crossed its boundaries. The final part of the manuscript is devoted to the study of this quantity. Note that the use of SPs may outperform the standard “Value at Risk" (VaR) method for two reasons: we can consider other market dynamics than the limited Wiener process and, even in this case, a risk level derived from the SP will ensure (within the desired quintile) that the quoted value of the portfolio will not leave the safety zone. We present some preliminary theoretical and applied results concerning this topic.

  4. A K-nearest neighbors survival probability prediction method.

    PubMed

    Lowsky, D J; Ding, Y; Lee, D K K; McCulloch, C E; Ross, L F; Thistlethwaite, J R; Zenios, S A

    2013-05-30

    We introduce a nonparametric survival prediction method for right-censored data. The method generates a survival curve prediction by constructing a (weighted) Kaplan-Meier estimator using the outcomes of the K most similar training observations. Each observation has an associated set of covariates, and a metric on the covariate space is used to measure similarity between observations. We apply our method to a kidney transplantation data set to generate patient-specific distributions of graft survival and to a simulated data set in which the proportional hazards assumption is explicitly violated. We compare the performance of our method with the standard Cox model and the random survival forests method. PMID:23653217

  5. Survival Prognosis in Very Old Adults

    PubMed Central

    Thinggaard, Mikael; McGue, Matt; Jeune, Bernard; Osler, Merete; Vaupel, James W.; Christensen, Kaare

    2016-01-01

    OBJECTIVES To determine whether simple functional indicators are predictors of survival prognosis in very old adults. DESIGN In-person survey conducted over a 3-month period in 1998; assessment of survival over a 15-year follow-up period. SETTING Denmark. PARTICIPANTS All 3,600 Danes born in 1905 and living in Denmark in 1998, were invited to participate regardless of residence and health; 2,262 (63%) participated in the survey: 1,814 (80.2%) in person and 448 (19.8%) through a proxy. MEASUREMENTS Socioeconomic factors, medications and diseases, activities of daily living, physical performance, cognition, depression symptomatology, self-rated health, and all-cause mortality, evaluated as average remaining lifespan and chance of surviving to 100 years. RESULTS Men aged 92 to 93 had an overall 6.0% chance of surviving to 100 years, whereas the chance for women was 11.4%. Being able to rise without use of hands increased the chance for men to 11.2% (95% confidence interval (CI) = 7.7–14.7) and for women to 22.0% (95% CI = 18.9–25.1). When combining this with a Mini-Mental State Examination (MMSE) scores from 28 to 30, the chances were 21.7% (95% CI = 11.5–31.9) for men and 34.2% (95% CI = 24.8–43.5) for women. CONCLUSION Chair stand score combined with MMSE score is a quick and easy way to estimate overall chance of survival in very old adults, which is particularly relevant when treatment with potential side effects for nonacute diseases is considered. J Am Geriatr Soc 64:81–88, 2016. PMID:26782855

  6. Survival probability of human conceptions from fertilization to term.

    PubMed

    Boklage, C E

    1990-01-01

    Preterm death of the human conceptus is common. A consistent biphasic pattern in the rate of loss from biochemical pregnancy detection to term suggests that most wastage occurs prior to clinical recognition. After simple adjustments for varying methods, existing data show that at least 73% of natural single conceptions have no real chance of surviving 6 weeks of gestation. Of the remainder, about 90% will survive to term. IVF conceptions do nearly as well as natural pregnancies after clinical recognition, but poorly before, despite selecting apparently normal embryos for transfer. Reasons may lie in the uterus more than the embryo itself. Multiple pregnancies may constitute more than 12% of all natural conceptions, of which number about 2% survive to term as twins and about 12% result in single births. In all of these situations, simple equations for exponential decay in a mixture of two populations can accurately describe the distribution of those deaths in time. PMID:1970983

  7. Recruitment in a Colorado population of big brown bats: Breeding probabilities, litter size, and first-year survival

    USGS Publications Warehouse

    O'Shea, T.J.; Ellison, L.E.; Neubaum, D.J.; Neubaum, M.A.; Reynolds, C.A.; Bowen, R.A.

    2010-01-01

    We used markrecapture estimation techniques and radiography to test hypotheses about 3 important aspects of recruitment in big brown bats (Eptesicus fuscus) in Fort Collins, Colorado: adult breeding probabilities, litter size, and 1st-year survival of young. We marked 2,968 females with passive integrated transponder (PIT) tags at multiple sites during 2001-2005 and based our assessments on direct recaptures (breeding probabilities) and passive detection with automated PIT tag readers (1st-year survival). We interpreted our data in relation to hypotheses regarding demographic influences of bat age, roost, and effects of years with unusual environmental conditions: extreme drought (2002) and arrival of a West Nile virus epizootic (2003). Conditional breeding probabilities at 6 roosts sampled in 2002-2005 were estimated as 0.64 (95% confidence interval [95% CI] = 0.530.73) in 1-year-old females, but were consistently high (95% CI = 0.940.96) and did not vary by roost, year, or prior year breeding status in older adults. Mean litter size was 1.11 (95% CI = 1.051.17), based on examination of 112 pregnant females by radiography. Litter size was not higher in older or larger females and was similar to results of other studies in western North America despite wide variation in latitude. First-year survival was estimated as 0.67 (95% CI = 0.610.73) for weaned females at 5 maternity roosts over 5 consecutive years, was lower than adult survival (0.79; 95% CI = 0.770.81), and varied by roost. Based on model selection criteria, strong evidence exists for complex roost and year effects on 1st-year survival. First-year survival was lowest in bats born during the drought year. Juvenile females that did not return to roosts as 1-year-olds had lower body condition indices in late summer of their natal year than those known to survive. ?? 2009 American Society of Mammalogists.

  8. The effect of maternal healthcare on the probability of child survival in Azerbaijan.

    PubMed

    Habibov, Nazim; Fan, Lida

    2014-01-01

    This study assesses the effects of maternal healthcare on child survival by using nonrandomized data from a cross-sectional survey in Azerbaijan. Using 2SLS and simultaneous equation bivariate probit models, we estimate the effects of delivering in healthcare facility on probability of child survival taking into account self-selection into the treatment. For women who delivered at healthcare facilities, the probability of child survival increases by approximately 18%. Furthermore, if every woman had the opportunity to deliver in healthcare facility, then the probability of child survival in Azerbaijan as a whole would have increased by approximately 16%. PMID:25110673

  9. Time preference and its relationship with age, health, and survival probability

    PubMed Central

    Chao, Li-Wei; Szrek, Helena; Pereira, Nuno Sousa; Pauly, Mark V.

    2009-01-01

    Although theories from economics and evolutionary biology predict that one's age, health, and survival probability should be associated with one's subjective discount rate (SDR), few studies have empirically tested for these links. Our study analyzes in detail how the SDR is related to age, health, and survival probability, by surveying a sample of individuals in townships around Durban, South Africa. In contrast to previous studies, we find that age is not significantly related to the SDR, but both physical health and survival expectations have a U-shaped relationship with the SDR. Individuals in very poor health have high discount rates, and those in very good health also have high discount rates. Similarly, those with expected survival probability on the extremes have high discount rates. Therefore, health and survival probability, and not age, seem to be predictors of one's SDR in an area of the world with high morbidity and mortality. PMID:20376300

  10. Time Dependence of the Survival Probability of AN Opinion in a Closed Community

    NASA Astrophysics Data System (ADS)

    Aydiner, Ekrem; Gönülol, Meltem

    The time dependence of the survival probability of an opinion in a closed community has been investigated in accordance with social temperature by using the Kawasaki-exchange dynamics based on previous study in Ref. 1. It is shown that the survival probability of opinion decays with stretched exponential law consistent with previous static model. However, the crossover regime in the decay of the survival probability has been observed in this dynamic model unlike previous model. The decay characteristics of both regimes obey to stretched exponential.

  11. Initial state maximizing the nonexponentially decaying survival probability for unstable multilevel systems

    NASA Astrophysics Data System (ADS)

    Miyamoto, Manabu

    2004-09-01

    The long-time behavior of the survival probability for unstable multilevel systems that follows the power-decay law is studied based on the N -level Friedrichs model, and is shown to depend on the initial population in unstable states. A special initial state maximizing the asymptote of the survival probability at long times is found and examined by considering the spontaneous-emission process for the hydrogen atom interacting with the electromagnetic field.

  12. Effects of amphibian chytrid fungus on individual survival probability in wild boreal toads.

    PubMed

    Pilliod, David S; Muths, Erin; Scherer, Rick D; Bartelt, Paul E; Corn, Paul Stephen; Hossack, Blake R; Lambert, Brad A; McCaffery, Rebecca; Gaughan, Christopher

    2010-10-01

    Chytridiomycosis is linked to the worldwide decline of amphibians, yet little is known about the demographic effects of the disease. We collected capture-recapture data on three populations of boreal toads (Bufo boreas [Bufo = Anaxyrus]) in the Rocky Mountains (U.S.A.). Two of the populations were infected with chytridiomycosis and one was not. We examined the effect of the presence of amphibian chytrid fungus (Batrachochytrium dendrobatidis [Bd]; the agent of chytridiomycosis) on survival probability and population growth rate. Toads that were infected with Bd had lower average annual survival probability than uninfected individuals at sites where Bd was detected, which suggests chytridiomycosis may reduce survival by 31-42% in wild boreal toads. Toads that were negative for Bd at infected sites had survival probabilities comparable to toads at the uninfected site. Evidence that environmental covariates (particularly cold temperatures during the breeding season) influenced toad survival was weak. The number of individuals in diseased populations declined by 5-7%/year over the 6 years of the study, whereas the uninfected population had comparatively stable population growth. Our data suggest that the presence of Bd in these toad populations is not causing rapid population declines. Rather, chytridiomycosis appears to be functioning as a low-level, chronic disease whereby some infected individuals survive but the overall population effects are still negative. Our results show that some amphibian populations may be coexisting with Bd and highlight the importance of quantitative assessments of survival in diseased animal populations. PMID:20412086

  13. Parent–offspring resemblance in colony-specific adult survival of cliff swallows

    USGS Publications Warehouse

    Brown, Charles R.; Roche, Erin A.; Brown, Mary Bomberger

    2015-01-01

    Survival is a key component of fitness. Species that occupy discrete breeding colonies with different characteristics are often exposed to varying costs and benefits associated with group size or environmental conditions, and survival is an integrative net measure of these effects. We investigated the extent to which survival probability of adult (≥1-year old) cliff swallows (Petrochelidon pyrrhonota) occupying different colonies resembled that of their parental cohort and thus whether the natal colony had long-term effects on individuals. Individuals were cross-fostered between colonies soon after hatching and their presence as breeders monitored at colonies in the western Nebraska study area for the subsequent decade. Colony-specific adult survival probabilities of offspring born and reared in the same colony, and those cross-fostered away from their natal colony soon after birth, were positively and significantly related to subsequent adult survival of the parental cohort from the natal colony. This result held when controlling for the effect of natal colony size and the age composition of the parental cohort. In contrast, colony-specific adult survival of offspring cross-fostered to a site was unrelated to that of their foster parent cohort or to the cohort of non-fostered offspring with whom they were reared. Adult survival at a colony varied inversely with fecundity, as measured by mean brood size, providing evidence for a survival–fecundity trade-off in this species. The results suggest some heritable variation in adult survival, likely maintained by negative correlations between fitness components. The study provides additional evidence that colonies represent non-random collections of individuals.

  14. Meta-analysis of two-arm studies: Modeling the intervention effect from survival probabilities.

    PubMed

    Combescure, C; Courvoisier, D S; Haller, G; Perneger, T V

    2016-04-01

    Pooling the hazard ratios is not always feasible in meta-analyses of two-arm survival studies, because the measure of the intervention effect is not systematically reported. An alternative approach proposed by Moodie et al. is to use the survival probabilities of the included studies, all collected at a single point in time: the intervention effect is then summarised as the pooled ratio of the logarithm of survival probabilities (which is an estimator of the hazard ratios when hazards are proportional). In this article, we propose a generalization of this method. By using survival probabilities at several points in time, this generalization allows a flexible modeling of the intervention over time. The method is applicable to partially proportional hazards models, with the advantage of not requiring the specification of the baseline survival. As in Moodie et al.'s method, the study-level factors modifying the survival functions can be ignored as long as they do not modify the intervention effect. The procedures of estimation are presented for fixed and random effects models. Two illustrative examples are presented. PMID:23267027

  15. Survival Probability of the Néel State in Clean and Disordered Systems: An Overview

    NASA Astrophysics Data System (ADS)

    Torres-Herrera, E. J.; Távora, Marco; Santos, Lea F.

    2016-06-01

    In this work we provide an overview of our recent results about the quench dynamics of one-dimensional many-body quantum systems described by spin-1/2 models. To illustrate those general results, here we employ a particular and experimentally accessible initial state, namely the Néel state. Both cases are considered: clean chains without any disorder and disordered systems with static random on-site magnetic fields. The quantity used for the analysis is the probability for finding the initial state later in time, the so-called survival probability. At short times, the survival probability may decay faster than exponentially, Gaussian behaviors and even the limit established by the energy-time uncertainty relation are displayed. The dynamics at long times slows down significantly and shows a powerlaw behavior. For both scenarios, we provide analytical expressions that agree very well with our numerical results.

  16. Effects of amphibian chytrid fungus on individual survival probability in wild boreal toads

    USGS Publications Warehouse

    Pilliod, D.S.; Muths, E.; Scherer, R. D.; Bartelt, P.E.; Corn, P.S.; Hossack, B.R.; Lambert, B.A.; Mccaffery, R.; Gaughan, C.

    2010-01-01

    Chytridiomycosis is linked to the worldwide decline of amphibians, yet little is known about the demographic effects of the disease. We collected capture-recapture data on three populations of boreal toads (Bufo boreas [Bufo = Anaxyrus]) in the Rocky Mountains (U.S.A.). Two of the populations were infected with chytridiomycosis and one was not. We examined the effect of the presence of amphibian chytrid fungus (Batrachochytrium dendrobatidis [Bd]; the agent of chytridiomycosis) on survival probability and population growth rate. Toads that were infected with Bd had lower average annual survival probability than uninfected individuals at sites where Bd was detected, which suggests chytridiomycosis may reduce survival by 31-42% in wild boreal toads. Toads that were negative for Bd at infected sites had survival probabilities comparable to toads at the uninfected site. Evidence that environmental covariates (particularly cold temperatures during the breeding season) influenced toad survival was weak. The number of individuals in diseased populations declined by 5-7%/year over the 6 years of the study, whereas the uninfected population had comparatively stable population growth. Our data suggest that the presence of Bd in these toad populations is not causing rapid population declines. Rather, chytridiomycosis appears to be functioning as a low-level, chronic disease whereby some infected individuals survive but the overall population effects are still negative. Our results show that some amphibian populations may be coexisting with Bd and highlight the importance of quantitative assessments of survival in diseased animal populations. Journal compilation. ?? 2010 Society for Conservation Biology. No claim to original US government works.

  17. Estimating annual survival and movement rates of adults within a metapopulation of roseate terns

    USGS Publications Warehouse

    Spendelow, J.A.; Nichols, J.D.; Nisbet, I.C.T.; Hays, H.; Cormons, G.D.; Burger, J.; Safina, C.; Hines, J.E.; Gochfeld, M.

    1995-01-01

    Several multistratum capture-recapture models were used to test various hypotheses about possible geographic and temporal variation in survival, movement, and recapture/resighting probabilities of 2399 adult Roseate Terns (Sterna dougallii) color-banded from 1988 to 1992 at the sites of the four largest breeding colonies of this species in the northeastern USA. Linear-logistic ultrastructural models also were developed to investigate possible correlates of geographic variation in movement probabilities. Based on goodness-of-fit tests and comparisons of Akaike's Information Criterion (AIC) values, the fully parameterized model (Model A) with time- and location-specific survival, movement, and capture probabilities, was selected as the most appropriate model for this metapopulation structure. With almost all movement accounted for, on average gt 90% of the surviving adults from each colony site returned to the same site the following year. Variations in movement probabilities were more closely associated with the identity of the destination colony site than with either the identity of the colony site of origin or the distance between colony sites. The average annual survival estimates (0.740.84) of terns from all four sites indicate a high rate of annual mortality relative to that of other species of marine birds.

  18. Survival probabilities with time-dependent treatment indicator: quantities and non-parametric estimators.

    PubMed

    Bernasconi, Davide Paolo; Rebora, Paola; Iacobelli, Simona; Valsecchi, Maria Grazia; Antolini, Laura

    2016-03-30

    The 'landmark' and 'Simon and Makuch' non-parametric estimators of the survival function are commonly used to contrast the survival experience of time-dependent treatment groups in applications such as stem cell transplant versus chemotherapy in leukemia. However, the theoretical survival functions corresponding to the second approach were not clearly defined in the literature, and the use of the 'Simon and Makuch' estimator was criticized in the biostatistical community. Here, we review the 'landmark' approach, showing that it focuses on the average survival of patients conditional on being failure free and on the treatment status assessed at the landmark time. We argue that the 'Simon and Makuch' approach represents counterfactual survival probabilities where treatment status is forced to be fixed: the patient is thought as under chemotherapy without possibility to switch treatment or as under transplant since the beginning of the follow-up. We argue that the 'Simon and Makuch' estimator leads to valid estimates only under the Markov assumption, which is however less likely to occur in practical applications. This motivates the development of a novel approach based on time rescaling, which leads to suitable estimates of the counterfactual probabilities in a semi-Markov process. The method is also extended to deal with a fixed landmark time of interest. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26503800

  19. The evolution of HPV-related anogenital cancers reported in Quebec - incidence rates and survival probabilities.

    PubMed

    Louchini, R; Goggin, P; Steben, M

    2008-01-01

    Non-cervical anogenital cancers (i.e. anal, vulvar, vaginal and penile cancers) associated with the human papillomavirus (HPV), for which HPV is known to be the necessary cause of carcinogenesis, are poorly documented due to their relatively low incidence rate. The aim of this study is to describe the incidence rates of these cancers between 1984 and 2001, and their relative survival probabilities, in Quebec (Canada) between 1984 and 1998. The incidence of these cancers is on the rise, particularly anal cancer in women and, more recently (since 1993-95), vulvar cancer. Between 1984-86 and 1993-95, the 5-year relative survival probability for men with anal cancer decreased from 57% to 46%, while that for penile cancer dropped from 75% to 59%. However, during the same period, the 5-year relative survival probability for women with anal cancer rose from 56% to 65%, and remained stable for cervical and vulvar cancers, at 74% and 82%, respectively. PMID:18341764

  20. Breeding productivity and adult survival in nongame birds

    USGS Publications Warehouse

    Martin, Thomas E.; DeSante, David F.; Paine, Charles R.; Donovan, Therese M.; Dettmers, Randy; Manolis, J.C.; Burton, K.

    1995-01-01

    Demographic data (breeding productivity and adult survival) provide the kind of early warning signal that allows detection of unhealthy populations in terms of productivity or survival problems (Martin and Guepel 1993). In addition, demographic data can help determine whether population declines are the result of low breeding productivity or low survival in migration or winter. Breeding productivity data also can help identify habitat conditions associated with successful and failed breeding attempts. Such information is critical for developing habitat- and land-management practices (Martin 1992). Here, we provide examples of the kinds of information that can be obtained by broad-scale demographic studies.

  1. Do ducks and songbirds initiate more nests when the probability of survival is greater?

    USGS Publications Warehouse

    Grant, Todd A.; Shaffer, Terry L.

    2015-01-01

    Nesting chronology in grassland birds can vary by species, locality, and year. The date a nest is initiated can influence the subsequent probability of its survival in some grassland bird species. Because predation is the most significant cause of nest loss in grassland birds, we examined the relation between timing of nesting and nest survival. Periods of high nest survival that correspond with the peak of nesting activity might reflect long-term adaptations to specific predation pressures commonly recurring during certain periods of the nesting cycle. We evaluated this theory by comparing timing of nesting with date-specific nest survival rates for several duck and passerine species breeding in north-central North Dakota during 1998–2003. Nest survival decreased seasonally with date for five of the seven species we studied. We found little evidence to support consistent relations between timing of nesting, the number of nest initiations, and nest survival for any species we studied, suggesting that factors other than nest predation may better explain nesting chronology for these species. The apparent mismatch between date-specific patterns of nest survival and nest initiation underscores uncertainty about the process of avian nest site selection driven mainly by predation. Although timing of nesting differed among species, the general nesting period was fairly predictable across all years of study, suggesting the potential for research activities or management actions to be timed to take advantage of known periods when nests are active (or inactive). However, our results do not support the notion that biologists can take advantage of periods when many nests are active and survival is also high.

  2. Modelling postfledging survival and age- specific breeding probabilities in species with delayed maturity: A case study of Roseate Terns at Falkner Island, Connecticut

    USGS Publications Warehouse

    Spendelow, J.A.; Nichols, J.D.; Hines, J.E.; Lebreton, J.D.; Pradel, R.

    2002-01-01

    We modelled postfledging survival and age-specific breeding probabilities in endangered Roseate Terns (Sterna dougallii) at Falkner Island, Connecticut, USA using capture-recapture data from 1988-1998 of birds ringed as chicks and as adults. While no individuals bred as 2-year-olds during this period, about three-quarters of the young that survived and returned as 3-year-olds nested, and virtually all surviving birds had begun breeding by the time they reached 5 years of age. We found no evidence of temporal variation age of first breeding of birds from different cohorts. There was significant temporal variation in the annual survival of adults and the survival over the typical 3-year maturation period of prebreeding birds, with extremely low values for both groups from the 1991 breeding season. The estimated overwinter survival rate (0.62) for adults from 1991-1992 was about three-quarters the usual rate of about 0.83, but the low survival of fledglings from 1991 resulted in less than 25% of the otherwise expected number of young from that cohort returning as breeding birds; this suggests that fledglings suffered a greater proportional decrease in survival than did adults. The survival estimates of young from 1989 and 1990 show that these cohorts were not negatively influenced by the events that decimated the young from 1991, and the young from 1992 and 1993 had above-average survival estimates. The apparent decrease since 1996 in development of fidelity of new recruits to this site is suspected to be due mainly to nocturnal disturbance and predation of chicks causing low productivity.

  3. Modelling postfledging survival and age-specific breeding probabilities in species with delayed maturity: a case study of Roseate Terns at Falkner Island, Connecticut

    USGS Publications Warehouse

    Spendelow, J.A.; Nichols, J.D.; Hines, J.E.; Lebreton, J.D.; Pradel, R.

    2002-01-01

    We modeled postfledging survival and age-specific breeding probabilities in endangered Roseate Terns (Sterna dougallii) at Falkner Island, Connecticut, USA using capture-recapture data from 1988-1998 of birds ringed as chicks and as adults. While no individuals bred as 2-yr-olds during this period, about three-quarters of the young that survived and returned as 3-yr-olds nested, and virtually all surviving birds had begun breeding by the time they reached 5 years of age. We found no evidence of temporal variation in age of first breeding of birds from different cohorts. There was significant temporal variation in the annual survival of adults and the survival over the typical 3-yr maturation period of prebreeding birds, with extremely low values for both groups from the 1991 breeding season. The estimated overwinter survival rate (0.62) for adults from 1991-1992 was about three-quarters the usual rate of about 0.83, but the low survival of fledglings from 1991 resulted in less than 25% of the otherwise expected number of young from that cohort returning as breeding birds; this suggests that fledglings suffered a greater proportional decrease in survival than did adults. The survival estimates of young from 1989 and 1990 show that these cohorts were not negatively influenced by the events that decimated the young from 1991, and the young from 1992 and 1993 had above-average survival estimates. The apparent decrease since 1996 in development of fidelity of new recruits to this site is suspected due mainly to nocturnal disturbance and predation of chicks causing low productivity.

  4. Monte Carlo based protocol for cell survival and tumour control probability in BNCT

    NASA Astrophysics Data System (ADS)

    Ye, Sung-Joon

    1999-02-01

    A mathematical model to calculate the theoretical cell survival probability (nominally, the cell survival fraction) is developed to evaluate preclinical treatment conditions for boron neutron capture therapy (BNCT). A treatment condition is characterized by the neutron beam spectra, single or bilateral exposure, and the choice of boron carrier drug (boronophenylalanine (BPA) or boron sulfhydryl hydride (BSH)). The cell survival probability defined from Poisson statistics is expressed with the cell-killing yield, the (n, ) reaction density, and the tolerable neutron fluence. The radiation transport calculation from the neutron source to tumours is carried out using Monte Carlo methods: (i) reactor-based BNCT facility modelling to yield the neutron beam library at an irradiation port; (ii) dosimetry to limit the neutron fluence below a tolerance dose (10.5 Gy-Eq); (iii) calculation of the (n, ) reaction density in tumours. A shallow surface tumour could be effectively treated by single exposure producing an average cell survival probability of - for probable ranges of the cell-killing yield for the two drugs, while a deep tumour will require bilateral exposure to achieve comparable cell kills at depth. With very pure epithermal beams eliminating thermal, low epithermal and fast neutrons, the cell survival can be decreased by factors of 2-10 compared with

  5. Solar wind evolution since 1990 and H ENA ionization rates and survival probabilities in the heliosphere

    NASA Astrophysics Data System (ADS)

    Sokol, J. M.; Kubiak, M. A.; Bzowski, M.; Tokumaru, M.; Fujiki, K.; McComas, D. J.; Bochsler, P.

    2012-04-01

    We derive the solar wind speed and density evolution in heliolatitude and time from 1990 to the end of 2011 based on remote-sensing and in-situ data sources in and out of the ecliptic plane and use it to calculate survival probabilities of heliospheric Energetic Neutral H Atoms (H ENA) in the energy range observed by the Interstellar Boundary Explorer (IBEX). We determine the heliolatitude structure of the solar wind speed using remote-sensing radio observations of interplanetary scintillations processed using the Computer Assisted Tomography algorithm and obtain yearly profiles on a 10-degree heliolatitude grid, which agree well with the in-situ measurements by Ulysses. Since the in-situ information on the solar wind density structure out of ecliptic is only available from the Ulysses data, we derive correlation formulae between solar wind speed and density profiles from Ulysses fast latitude scans and calculate the 3D structure of solar wind density. For the ecliptic heliolatitude band we use in-situ measurements from the OMNI-2 collection. Having obtained evolution of solar wind speed and density in time and heliolatitude, to calculate the ionization rate of H ENA we need the photoionization rate of H, which we obtain from TIMED SEE and SOHO CELIAS/SEM measurements supplemented with proxies. With the history of evolution of the solar factors responsible for the ionization of H ENA derived, we calculate the survival probabilities of H ENA observed by IBEX. To that end, we employ an atom-tracing approach. We track the atom trajectories from IBEX backwards in time up to the termination shock, solving the equation of motion and simultaneously calculating the survival probability against ionization. The equation of motion includes the forces of solar gravity and radiation pressure, which is a function of the total solar flux in the Lyman-alpha line and of radial velocity of the atom relative to the Sun due to the Doppler effect. To model the radiation pressure, we

  6. Temperature-Dependent Survival of Adult Lygus hesperus (Hemiptera: Miridae).

    PubMed

    Cooper, W Rodney; Spurgeon, Dale W

    2015-06-01

    The western tarnished plant bug, Lygus hesperus Knight (Hemiptera: Miridae), is a key pest of many horticultural and agronomic crops in the western United States. Despite its well documented pest status, many aspects of the basic biology, including overwintering ecology, of L. hesperus are poorly understood. We examined the influence of eight constant temperatures from 10 to 35°C on survival of nondiapausing adult L. hesperus held with or without food, and the consequences of exposure to an extended period at 10°C on subsequent reproduction. Survival analyses indicated that, on average, fed insects tended to live longer than unfed insects, females lived longer than males, and the survival time decreased with increasing temperature. Nonlinear regressions indicated that median survival for insects grouped by gender and feeding status declined exponentially with increasing temperature. Survival functions for combinations of insect class (gender and feeding status) and temperature were adequately described by the respective two-parameter logistic functions. When adults were held for 9 d at 27°C with food after a 33-d period at 10°C either with or without food, no deleterious effects of prior starvation on propensity to mate or fecundity were demonstrated. These findings indicate that when temperatures are low, nondiapausing L. hesperus adults are capable of extended host-free survival with little or no impact on subsequent reproduction. Our findings suggest the current understanding of L. hesperus overwintering dynamics is incomplete. In addition, our results provide quantitative baseline information to facilitate more comprehensive investigation of the ecology of L. hesperus overwintering. PMID:26313987

  7. Estimation of survival of adult Florida manatees in the Crystal River, at Blue Spring, and on the Atlantic Coast

    USGS Publications Warehouse

    O'Shea, Thomas J.; Langtimm, Catherine A.

    1995-01-01

    We applied Cormack-Jolly-Seber open population models to manatee (Trichechus manatus latirostris) photo-identification databases to estimate adult survival probabilities. The computer programs JOLLY and RECAPCO were used to estimate survival of 677 individuals in three study areas: Crystal River (winters 1977-78 to 1990-91), Blue Spring (winters 1977-78 to 1990-91), and the Atlantic Coast (winters 1984-85 to 1990-91). We also estimated annual survival from observations of 111 manatees tagged for studies with radiotelemetry. Survival estimated from observations with telemetry had broader confidence intervals than survival estimated with the Cormack-Jolly-Seber models. Annual probabilities of capture based on photo-identification records were generally high. The mean annual adult survival estimated from sighting-resighting records was 0.959-0.962 in the Crystal River and 0.936-0.948 at Blue Spring and may be high enough to permit population growth, given the values of other life-history parameters. On the Atlantic Coast, the estimated annual adult survival (range of means = 0.877-0.885) may signify a declining population. However, for several reasons, interpretation of data from the latter study group should be tempered with caution. Adult survivorship seems to be constant with age in all three study groups. No strong differences were apparent between adult survival ofmales and females in the Crystal River or at Blue Spring; the basis of significant differences between sexes on the Atlantic Coast is unclear. Future research into estimating survival with photo-identification and the Cormack-Jolly-Seber models should be vigorously pursued. Estimates of annual survival can provide an additional indication of Florida manatee population status with a stronger statistical basis than aerial counts and carcass totals.

  8. Dietary variety increases the probability of nutrient adequacy among adults.

    PubMed

    Foote, Janet A; Murphy, Suzanne P; Wilkens, Lynne R; Basiotis, P Peter; Carlson, Andrea

    2004-07-01

    Despite guidance to consume a variety of foods, the role of dietary variety in ensuring nutrient adequacy is unclear. The aim of this study was to determine whether a commodity-based measure of dietary variety was associated with the probability of nutrient adequacy after adjusting for energy and food group intakes. Subjects were 4969 men and 4800 women >/= 19 y old who participated in the Continuing Survey of Food Intakes for Individuals 1994-1996. Using 24-h recall data, the mean probability of adequacy across 15 nutrients was calculated using the Dietary Reference Intakes. Dietary variety was defined using a commodity-based method similar to that used for the Healthy Eating Index (HEI). Associations were examined in gender-specific multivariate regression models. Energy intake was a strong predictor of the mean probability of adequacy in models controlled for age, BMI, education level, and ethnicity (model R(2) = 0.60 and 0.54 for men and women, respectively). Adding the number of servings from each of the 5 Food Guide Pyramid (FGP) groups to the models significantly improved the model fit (R(2) = 0.69 and 0.66 for men and women). Adding dietary variety again significantly improved the model fit for both men and women (R(2) = 0.73 and 0.70, respectively). Variety counts within the dairy and grain groups were most strongly associated with improved nutrient adequacy. Dietary variety as defined by the HEI contributes an additional component of dietary quality that is not captured by FGP servings or energy intake. PMID:15226469

  9. Adult Rhabdomyosarcoma Survival Improved With Treatment on Multimodality Protocols

    SciTech Connect

    Gerber, Naamit Kurshan; Wexler, Leonard H.; Singer, Samuel; Alektiar, Kaled M.; Keohan, Mary Louise; Shi, Weiji; Zhang, Zhigang; Wolden, Suzanne

    2013-05-01

    Purpose: Rhabdomyosarcoma (RMS) is a pediatric sarcoma rarely occurring in adults. For unknown reasons, adults with RMS have worse outcomes than do children. Methods and Materials: We analyzed data from all patients who presented to Memorial Sloan-Kettering Cancer Center between 1990 and 2011 with RMS diagnosed at age 16 or older. One hundred forty-eight patients met the study criteria. Ten were excluded for lack of adequate data. Results: The median age was 28 years. The histologic diagnoses were as follows: embryonal 54%, alveolar 33%, pleomorphic 12%, and not otherwise specified 2%. The tumor site was unfavorable in 67% of patients. Thirty-three patients (24%) were at low risk, 61 (44%) at intermediate risk, and 44 (32%) at high risk. Forty-six percent were treated on or according to a prospective RMS protocol. The 5-year rate of overall survival (OS) was 45% for patients with nonmetastatic disease. The failure rates at 5 years for patients with nonmetastatic disease were 34% for local failure and 42% for distant failure. Among patients with nonmetastatic disease (n=94), significant factors associated with OS were histologic diagnosis, site, risk group, age, and protocol treatment. On multivariate analysis, risk group and protocol treatment were significant after adjustment for age. The 5-year OS was 54% for protocol patients versus 36% for nonprotocol patients. Conclusions: Survival in adult patients with nonmetastatic disease was significantly improved for those treated on RMS protocols, most of which are now open to adults.

  10. Survival of adult female elk in yellowstone following wolf restoration

    USGS Publications Warehouse

    Evans, S.B.; Mech, L.D.; White, P.J.; Sargeant, G.A.

    2006-01-01

    Counts of northern Yellowstone elk (Cervus elaphus) in northwestern Wyoming and adjacent Montana, USA, have decreased at an average rate of 6-8% per year since wolves (Canis lupus) were reintroduced in 1995. Population growth rates of elk are typically sensitive to variations in adult female survival; populations that are stable or increasing exhibit high adult female survival. We used survival records for 85 radiocollared adult female elk 1-19 years old to estimate annual survival from March 2000 to February 2004. Weighted average annual survival rates were approximately 0.83 (95% CI = 0.77-0.89) for females 1-15 years old and 0.80 (95% CI = 0.73-0.86) for all females. Our estimates were much lower than the rate of 0.99 observed during 1969-1975 when fewer elk were harvested by hunters, wolves were not present, and other predators were less numerous. Of 33 documented deaths included in our analysis, we attributed 11 to hunter harvest, 14 to predation (10 wolf, 2 unknown, 1 cougar [Puma concolor], and 1 bear [Ursus sp.]), 6 to unknown causes, and 2 to winter-kill. Most deaths occurred from December through March. Estimates of cause-specific annual mortality rates were 0.09 (0.05-0.14) for all predators, 0.08 (0.04-0.13) for hunting, and 0.07 (0.03-0.11) for wolves specifically. Wolf-killed elk were typically older (median = 12 yr) than hunter-killed elk (median = 9 yr, P = 0.03). However, elk that winter outside the park where they were exposed to hunting were also younger (median = 7 yr) than elk that we did not observe outside the park (median = 9 yr, P < 0.01). Consequently, differences in ages of elk killed by wolves and hunters may reflect characteristics of elk exposed to various causes of mortality, as well as differences in susceptibility. Unless survival rates of adult females increase, elk numbers are likely to continue declining. Hunter harvest is the only cause of mortality that is amenable to management at the present time.

  11. Passage and survival probabilities of juvenile Chinook salmon at Cougar Dam, Oregon, 2012

    USGS Publications Warehouse

    Beeman, John W.; Evans, Scott D.; Haner, Philip V.; Hansel, Hal C.; Hansen, Amy C.; Smith, Collin D.; Sprando, Jamie M.

    2014-01-01

    This report describes studies of juvenile-salmon dam passage and apparent survival at Cougar Dam, Oregon, during two operating conditions in 2012. Cougar Dam is a 158-meter tall rock-fill dam used primarily for flood control, and passes water through a temperature control tower to either a powerhouse penstock or to a regulating outlet (RO). The temperature control tower has moveable weir gates to enable water of different elevations and temperatures to be drawn through the dam to control water temperatures downstream. A series of studies of downstream dam passage of juvenile salmonids were begun after the National Oceanic and Atmospheric Administration determined that Cougar Dam was impacting the viability of anadromous fish stocks. The primary objectives of the studies described in this report were to estimate the route-specific fish passage probabilities at the dam and to estimate the survival probabilities of fish passing through the RO. The first set of dam operating conditions, studied in November, consisted of (1) a mean reservoir elevation of 1,589 feet, (2) water entering the temperature control tower through the weir gates, (3) most water routed through the turbines during the day and through the RO during the night, and (4) mean RO gate openings of 1.2 feet during the day and 3.2 feet during the night. The second set of dam operating conditions, studied in December, consisted of (1) a mean reservoir elevation of 1,507 ft, (2) water entering the temperature control tower through the RO bypass, (3) all water passing through the RO, and (4) mean RO gate openings of 7.3 feet during the day and 7.5 feet during the night. The studies were based on juvenile Chinook salmon (Oncorhynchus tshawytscha) surgically implanted with radio transmitters and passive integrated transponder (PIT) tags. Inferences about general dam passage percentage and timing of volitional migrants were based on surface-acclimated fish released in the reservoir. Dam passage and apparent

  12. Cluster geometry and survival probability in systems driven by reaction diffusion dynamics

    NASA Astrophysics Data System (ADS)

    Windus, Alastair; Jensen, Henrik J.

    2008-11-01

    We consider a reaction-diffusion model incorporating the reactions A→phi, A→2A and 2A→3A. Depending on the relative rates for sexual and asexual reproduction of the quantity A, the model exhibits either a continuous or first-order absorbing phase transition to an extinct state. A tricritical point separates the two phase lines. While we comment on this critical behaviour, the main focus of the paper is on the geometry of the population clusters that form. We observe the different cluster structures that arise at criticality for the three different types of critical behaviour and show that there exists a linear relationship for the survival probability against initial cluster size at the tricritical point only.

  13. Time-Dependence of the Survival Probability of Quarkonia in Quark-Gluon Plasma

    NASA Astrophysics Data System (ADS)

    Mah Hussin, Noor Sabrina; Shalaby, Asmaa; Petridis, Athanasios

    2015-10-01

    The time-dependent Schrödinger equation is used to study the formation of quarkonia and their propagation in Quark-Gluon Plasma (QGP). The initial bound (ground) state is computed using imaginary-time propagation in a confining potential. The QGP is simulated with a confining potential of an extended asymptotic freedom region. The interior of the QGP potential may correspond to a vacuum that differs from that of the exterior region. The initial state propagates through this potential in real time. The survival probability is calculated versus time for various potential parameters and relative momenta of the quarkonium by projecting the interacting wavefunction onto its freely-propagating counterpart. In these calculations the staggered-leap frog method is used with special attention paid to the issue of stability. It is found that quarkonium decay is typically non-exponential. Fast moving states decay faster. Connection with experimental results is done by means of cross-section ratios.

  14. Shifting Effects of Ocean Conditions on Survival and Breeding Probability of a Long-Lived Seabird.

    PubMed

    Schmidt, Annie E; Dybala, Kristen E; Botsford, Louis W; Eadie, John M; Bradley, Russell W; Jahncke, Jaime

    2015-01-01

    With a rapidly changing climate, there is an increasing need to predict how species will respond to changes in the physical environment. One approach is to use historic data to estimate the past influence of environmental variation on important demographic parameters and then use these relationships to project the abundance of a population or species under future climate scenarios. However, as novel climate conditions emerge, novel species responses may also appear. In some systems, environmental conditions beyond the range of those observed during the course of most long-term ecological studies are already evident. Yet little attention has been given to how these novel conditions may be influencing previously established environment-species relationships. Here, we model the relationships between ocean conditions and the demography of a long-lived seabird, Brandt's cormorant (Phalacrocorax penicillatusI), in central California and show that these relationships have changed in recent years. Beginning in 2007/2008, the response of Brandt's cormorant, an upper trophic level predator, to ocean conditions shifted, resulting in lower than predicted survival and breeding probability. Survival was generally less variable than breeding probability and was initially best predicted by the basin-scale forcing of the El Niño Southern Oscillation rather than local ocean conditions. The shifting response of Brandt's cormorant to ocean conditions may be just a proximate indication of altered dynamics in the food web and that important forage fish are not responding to the physical ocean environment as expected. These changing relationships have important implications for our ability to project the effects of future climate change for species and communities. PMID:26168050

  15. Shifting Effects of Ocean Conditions on Survival and Breeding Probability of a Long-Lived Seabird

    PubMed Central

    Schmidt, Annie E.; Dybala, Kristen E.; Botsford, Louis W.; Eadie, John M.; Bradley, Russell W.; Jahncke, Jaime

    2015-01-01

    With a rapidly changing climate, there is an increasing need to predict how species will respond to changes in the physical environment. One approach is to use historic data to estimate the past influence of environmental variation on important demographic parameters and then use these relationships to project the abundance of a population or species under future climate scenarios. However, as novel climate conditions emerge, novel species responses may also appear. In some systems, environmental conditions beyond the range of those observed during the course of most long-term ecological studies are already evident. Yet little attention has been given to how these novel conditions may be influencing previously established environment–species relationships. Here, we model the relationships between ocean conditions and the demography of a long-lived seabird, Brandt’s cormorant (Phalacrocorax penicillatusI), in central California and show that these relationships have changed in recent years. Beginning in 2007/2008, the response of Brandt’s cormorant, an upper trophic level predator, to ocean conditions shifted, resulting in lower than predicted survival and breeding probability. Survival was generally less variable than breeding probability and was initially best predicted by the basin-scale forcing of the El Niño Southern Oscillation rather than local ocean conditions. The shifting response of Brandt’s cormorant to ocean conditions may be just a proximate indication of altered dynamics in the food web and that important forage fish are not responding to the physical ocean environment as expected. These changing relationships have important implications for our ability to project the effects of future climate change for species and communities. PMID:26168050

  16. Survival probability of precipitations and rain attenuation in tropical and equatorial regions

    NASA Astrophysics Data System (ADS)

    Mohebbi Nia, Masoud; Din, Jafri; Panagopoulos, Athanasios D.; Lam, Hong Yin

    2015-08-01

    This contribution presents a stochastic model useful for the generation of a long-term tropospheric rain attenuation time series for Earth space or a terrestrial radio link in tropical and equatorial heavy rain regions based on the well-known Cox-Ingersoll-Ross model previously employed in research in the fields of finance and economics. This model assumes typical gamma distribution for rain attenuation in heavy rain climatic regions and utilises the temporal dynamic of precipitation collected in equatorial Johor, Malaysia. Different formations of survival probability are also discussed. Furthermore, the correlation between these probabilities and the Markov process is determined, and information on the variance and autocorrelation function of rain events with respect to the particular characteristics of precipitation in this area is presented. The proposed technique proved to preserve the peculiarities of precipitation for an equatorial region and reproduce fairly good statistics of the rain attenuation correlation function that could help to improve the prediction of dynamic characteristics of rain fade events.

  17. Effects of ambient air temperature, humidity and rainfall on annual survival of adult little penguins Eudyptula minor in southeastern Australia.

    PubMed

    Ganendran, L B; Sidhu, L A; Catchpole, E A; Chambers, L E; Dann, P

    2016-08-01

    Seabirds are subject to the influences of local climate variables during periods of land-based activities such as breeding and, for some species, moult; particularly if they undergo a catastrophic moult (complete simultaneous moult) as do penguins. We investigated potential relationships between adult penguin survival and land-based climate variables (ambient air temperature, humidity and rainfall) using 46 years of mark-recapture data of little penguins Eudyptula minor gathered at a breeding colony on Phillip Island in southeastern Australia. Our results showed that adult penguin survival had a stronger association with land-based climate variables during the moult period, when birds were unable to go to sea for up to 3 weeks, than during the breeding period, when birds could sacrifice breeding success in favour of survival. Annual adult survival probability was positively associated with humidity during moult and negatively associated with rainfall during moult. Prolonged heat during breeding and moult had a negative association with annual adult survival. Local climate projections suggest increasing days of high temperatures, fewer days of rainfall which will result in more droughts (and by implication, lower humidity) and more extreme rainfall events. All of these predicted climate changes are expected to have a negative impact on adult penguin survival. PMID:26698160

  18. Effects of ambient air temperature, humidity and rainfall on annual survival of adult little penguins Eudyptula minor in southeastern Australia

    NASA Astrophysics Data System (ADS)

    Ganendran, L. B.; Sidhu, L. A.; Catchpole, E. A.; Chambers, L. E.; Dann, P.

    2015-12-01

    Seabirds are subject to the influences of local climate variables during periods of land-based activities such as breeding and, for some species, moult; particularly if they undergo a catastrophic moult (complete simultaneous moult) as do penguins. We investigated potential relationships between adult penguin survival and land-based climate variables (ambient air temperature, humidity and rainfall) using 46 years of mark-recapture data of little penguins Eudyptula minor gathered at a breeding colony on Phillip Island in southeastern Australia. Our results showed that adult penguin survival had a stronger association with land-based climate variables during the moult period, when birds were unable to go to sea for up to 3 weeks, than during the breeding period, when birds could sacrifice breeding success in favour of survival. Annual adult survival probability was positively associated with humidity during moult and negatively associated with rainfall during moult. Prolonged heat during breeding and moult had a negative association with annual adult survival. Local climate projections suggest increasing days of high temperatures, fewer days of rainfall which will result in more droughts (and by implication, lower humidity) and more extreme rainfall events. All of these predicted climate changes are expected to have a negative impact on adult penguin survival.

  19. Effects of ambient air temperature, humidity and rainfall on annual survival of adult little penguins Eudyptula minor in southeastern Australia

    NASA Astrophysics Data System (ADS)

    Ganendran, L. B.; Sidhu, L. A.; Catchpole, E. A.; Chambers, L. E.; Dann, P.

    2016-08-01

    Seabirds are subject to the influences of local climate variables during periods of land-based activities such as breeding and, for some species, moult; particularly if they undergo a catastrophic moult (complete simultaneous moult) as do penguins. We investigated potential relationships between adult penguin survival and land-based climate variables (ambient air temperature, humidity and rainfall) using 46 years of mark-recapture data of little penguins Eudyptula minor gathered at a breeding colony on Phillip Island in southeastern Australia. Our results showed that adult penguin survival had a stronger association with land-based climate variables during the moult period, when birds were unable to go to sea for up to 3 weeks, than during the breeding period, when birds could sacrifice breeding success in favour of survival. Annual adult survival probability was positively associated with humidity during moult and negatively associated with rainfall during moult. Prolonged heat during breeding and moult had a negative association with annual adult survival. Local climate projections suggest increasing days of high temperatures, fewer days of rainfall which will result in more droughts (and by implication, lower humidity) and more extreme rainfall events. All of these predicted climate changes are expected to have a negative impact on adult penguin survival.

  20. Quantifying the impact of longline fisheries on adult survival in the black-footed albatross

    USGS Publications Warehouse

    Veran, S.; Gimenez, O.; Flint, E.; Kendall, W.L.; Doherty, P.F., Jr.; Lebreton, J.D.

    2007-01-01

    1. Industrial longline fishing has been suspected to impact upon black-footed albatross populations Phoebastria nigripes by increasing mortality, but no precise estimates of bycatch mortality are available to ascertain this statement. We present a general framework for quantifying the relationship between albatross population and longline fishing in absence of reliable estimates of bycatch rate. 2. We analysed capture?recapture data of a population of black-footed albatross to obtain estimates of survival probability for this population using several alternative models to adequately take into account heterogeneity in the recapture process. Instead of trying to estimate the number of birds killed by using various extrapolations and unchecked assumptions, we investigate the potential relationship between annual adult survival and several measures of fishing effort. Although we considered a large number of covariates, we used principal component analysis to generate a few uncorrelated synthetic variables from the set and thus we maintained both power and robustness. 3. The average survival for 1997?2002 was 92%, a low value compared to estimates available for other albatross species. We found that one of the synthetic variables used to summarize industrial longline fishing significantly explained more than 40% of the variation in adult survival over 11 years, suggesting an impact by longline fishing on albatross? survival. 4. Our analysis provides some evidence of non-linear variation in survival with fishing effort. This could indicate that below a certain level of fishing effort, deaths due to incidental catch can be partially or totally compensated for by a decrease in natural mortality. Another possible explanation is the existence of a strong interspecific competition for accessing the baits, reducing the risk of being accidentally hooked. 5. Synthesis and applications. The suspicion of a significant impact of longline fishing on the black-footed albatross

  1. Notes on the Lumped Backward Master Equation for the Neutron Extinction/Survival Probability

    SciTech Connect

    Prinja, Anil K

    2012-07-02

    chains (a fission chain is defined as the initial source neutron and all its subsequent progeny) in which some chains are short lived while others propagate for unusually long times. Under these conditions, fission chains do not overlap strongly and this precludes the cancellation of neutron number fluctuations necessary for the mean to become established as the dominant measure of the neutron population. The fate of individual chains then plays a defining role in the evolution of the neutron population in strongly stochastic systems, and of particular interest and importance in supercritical systems is the extinction probability, defined as the probability that the neutron chain (initiating neutron and its progeny) will be extinguished at a particular time, or its complement, the time-dependent survival probability. The time-asymptotic limit of the latter, the probability of divergence, gives the probability that the neutron population will grow without bound, and is more commonly known as the probability of initiation or just POI. The ability to numerically compute these probabilities, with high accuracy and without overly restricting the underlying physics (e.g., fission neutron multiplicity, reactivity variation) is clearly essential in developing an understanding of the behavior of strongly stochastic systems.

  2. Importance of adult survival, local recruitment and immigration in a declining boreal forest passerine, the willow tit Parus montanus.

    PubMed

    Lampila, Satu; Orell, Markku; Belda, Eduardo; Koivula, Kari

    2006-06-01

    Population growth rate (lambda) and its components (adult survival, local recruitment, immigration and their relative contributions to lambda) were studied in the declining willow tit Parus montanus in Northern Finland. Capture-recapture models for open populations were used to estimate the population parameters and their process variation. Adult survival was fairly high with low variation (0.593, CV=0.067). As expected, local recruitment was lower and more variable (0.063, CV=0.610). During the 12-year study, the population growth rate averaged to one (0.988, CV=0.197; calculated as [see text]. However, if the present processes continue, population projections show that the population is likely to decline. There was considerable temporal variation in the relative contributions of demographic parameters to lambda. In all years, adult survival had the highest relative contribution (mean 64%) to the population growth rate and it was the least variable trait. Immigration had a higher relative contribution (22%) to lambda than local recruitment (14%). Based on the results for the contributions to lambda, the main conservation concern for willow tits is adult survival. Due to low variation, adult survival may be difficult to enhance, but at least it should be prevented from declining. High stochasticity in local recruitment and immigration is probably an inherent characteristic of highly seasonal environments, making these traits difficult to address for conservation practices. PMID:16514536

  3. Transcriptomic and Proteomic Analysis of Arion vulgaris—Proteins for Probably Successful Survival Strategies?

    PubMed Central

    Bulat, Tanja; Smidak, Roman; Sialana, Fernando J.; Jung, Gangsoo; Rattei, Thomas; Bilban, Martin; Sattmann, Helmut; Lubec, Gert; Aradska, Jana

    2016-01-01

    The Spanish slug, Arion vulgaris, is considered one of the hundred most invasive species in Central Europe. The immense and very successful adaptation and spreading of A. vulgaris suggest that it developed highly effective mechanisms to deal with infections and natural predators. Current transcriptomic and proteomic studies on gastropods have been restricted mainly to marine and freshwater gastropods. No transcriptomic or proteomic study on A. vulgaris has been carried out so far, and in the current study, the first transcriptomic database from adult specimen of A. vulgaris is reported. To facilitate and enable proteomics in this non-model organism, a mRNA-derived protein database was constructed for protein identification. A gel-based proteomic approach was used to obtain the first generation of a comprehensive slug mantle proteome. A total of 2128 proteins were unambiguously identified; 48 proteins represent novel proteins with no significant homology in NCBI non-redundant database. Combined transcriptomic and proteomic analysis revealed an extensive repertoire of novel proteins with a role in innate immunity including many associated pattern recognition, effector proteins and cytokine-like proteins. The number and diversity in gene families encoding lectins point to a complex defense system, probably as a result of adaptation to a pathogen-rich environment. These results are providing a fundamental and important resource for subsequent studies on molluscs as well as for putative antimicrobial compounds for drug discovery and biomedical applications. PMID:26986963

  4. Transcriptomic and Proteomic Analysis of Arion vulgaris--Proteins for Probably Successful Survival Strategies?

    PubMed

    Bulat, Tanja; Smidak, Roman; Sialana, Fernando J; Jung, Gangsoo; Rattei, Thomas; Bilban, Martin; Sattmann, Helmut; Lubec, Gert; Aradska, Jana

    2016-01-01

    The Spanish slug, Arion vulgaris, is considered one of the hundred most invasive species in Central Europe. The immense and very successful adaptation and spreading of A. vulgaris suggest that it developed highly effective mechanisms to deal with infections and natural predators. Current transcriptomic and proteomic studies on gastropods have been restricted mainly to marine and freshwater gastropods. No transcriptomic or proteomic study on A. vulgaris has been carried out so far, and in the current study, the first transcriptomic database from adult specimen of A. vulgaris is reported. To facilitate and enable proteomics in this non-model organism, a mRNA-derived protein database was constructed for protein identification. A gel-based proteomic approach was used to obtain the first generation of a comprehensive slug mantle proteome. A total of 2128 proteins were unambiguously identified; 48 proteins represent novel proteins with no significant homology in NCBI non-redundant database. Combined transcriptomic and proteomic analysis revealed an extensive repertoire of novel proteins with a role in innate immunity including many associated pattern recognition, effector proteins and cytokine-like proteins. The number and diversity in gene families encoding lectins point to a complex defense system, probably as a result of adaptation to a pathogen-rich environment. These results are providing a fundamental and important resource for subsequent studies on molluscs as well as for putative antimicrobial compounds for drug discovery and biomedical applications. PMID:26986963

  5. Annual survival rates of adult and immature eastern population tundra swans

    USGS Publications Warehouse

    Nichols, J.D.; Bart, J.; Limpert, R.J.; Sladen, William J. L.; Hines, J.E.

    1992-01-01

    Tundra swans (Cygnus columbianus ) of the eastern population were neckbanded in Maryland, North Carolina, and Alaska from 1966 through 1990. These swans were resighted and recaptured during autumn, winter, and spring, 1966-1990. Although the original motivation for this study involved swan movements, we wanted to use the resulting data to test hypotheses about sources of variation in swan survival rates. Recaptures of legbanded and neckbanded swans permitted us to estimate neckband loss rates, which were found to vary with age and sex of swans, and number of years since initial application. Estimates of annual neckband retention rate ranged from about 0.50 for adult male swans greater than or equal to 2 years after initial neckbanding to > 0.96 for immature swans and adult females the first year following neckbanding. This variation in neckband loss rates prevented the simple correction of survival estimates to account for such loss. Consequently, we developed a series of multinomial models parameterized with survival, sighting, and neckband retention probabilities for use with the recapture and resighting data.

  6. INCLUDING TRANSITION PROBABILITIES IN NEST SURVIVAL ESTIMATION: A MAYFIELD MARKOV CHAIN

    EPA Science Inventory

    This manuscript is primarily an exploration of the statistical properties of nest-survival estimates for terrestrial songbirds. The Mayfield formulation described herein should allow researchers to test for complicated effects of stressors on daily survival and overall success, i...

  7. A comparison of conventional capture versus PIT reader techniques for estimating survival and capture probabilities of big brown bats (Eptesicus fuscus)

    USGS Publications Warehouse

    Ellison, L.E.; O'Shea, T.J.; Neubaum, D.J.; Neubaum, M.A.; Pearce, R.D.; Bowen, R.A.

    2007-01-01

    We compared conventional capture (primarily mist nets and harp traps) and passive integrated transponder (PIT) tagging techniques for estimating capture and survival probabilities of big brown bats (Eptesicus fuscus) roosting in buildings in Fort Collins, Colorado. A total of 987 female adult and juvenile bats were captured and marked by subdermal injection of PIT tags during the summers of 2001-2005 at five maternity colonies in buildings. Openings to roosts were equipped with PIT hoop-style readers, and exit and entry of bats were passively monitored on a daily basis throughout the summers of 2002-2005. PIT readers 'recaptured' adult and juvenile females more often than conventional capture events at each roost. Estimates of annual capture probabilities for all five colonies were on average twice as high when estimated from PIT reader data (P?? = 0.93-1.00) than when derived from conventional techniques (P?? = 0.26-0.66), and as a consequence annual survival estimates were more precisely estimated when using PIT reader encounters. Short-term, daily capture estimates were also higher using PIT readers than conventional captures. We discuss the advantages and limitations of using PIT tags and passive encounters with hoop readers vs. conventional capture techniques for estimating these vital parameters in big brown bats. ?? Museum and Institute of Zoology PAS.

  8. Measuring Adult Mortality Using Sibling Survival: A New Analytical Method and New Results for 44 Countries, 1974–2006

    PubMed Central

    Obermeyer, Ziad; Rajaratnam, Julie Knoll; Park, Chang H.; Gakidou, Emmanuela; Hogan, Margaret C.; Lopez, Alan D.; Murray, Christopher J. L.

    2010-01-01

    Background For several decades, global public health efforts have focused on the development and application of disease control programs to improve child survival in developing populations. The need to reliably monitor the impact of such intervention programs in countries has led to significant advances in demographic methods and data sources, particularly with large-scale, cross-national survey programs such as the Demographic and Health Surveys (DHS). Although no comparable effort has been undertaken for adult mortality, the availability of large datasets with information on adult survival from censuses and household surveys offers an important opportunity to dramatically improve our knowledge about levels and trends in adult mortality in countries without good vital registration. To date, attempts to measure adult mortality from questions in censuses and surveys have generally led to implausibly low levels of adult mortality owing to biases inherent in survey data such as survival and recall bias. Recent methodological developments and the increasing availability of large surveys with information on sibling survival suggest that it may well be timely to reassess the pessimism that has prevailed around the use of sibling histories to measure adult mortality. Methods and Findings We present the Corrected Sibling Survival (CSS) method, which addresses both the survival and recall biases that have plagued the use of survey data to estimate adult mortality. Using logistic regression, our method directly estimates the probability of dying in a given country, by age, sex, and time period from sibling history data. The logistic regression framework borrows strength across surveys and time periods for the estimation of the age patterns of mortality, and facilitates the implementation of solutions for the underrepresentation of high-mortality families and recall bias. We apply the method to generate estimates of and trends in adult mortality, using the summary measure 45q

  9. Variations in the survival probabilities of the PVC-protected red mangrove propagules: testing the encased replanting technique.

    PubMed

    López-Ortiz, M I; Pérez, C M; Suárez, E; Ríos-Dávila, R

    1999-12-01

    The EcoEléctrica Mangrove Planting Project, a five-year voluntary effort, has the purpose of testing a recently developed mangrove planting technique at the EcoEléctrica site in Peñuelas, Puerto Rico. The goal of the project is to provide empirical validation to promote or improve the technique to be used in recovering mangrove ecosystems in Puerto Rico and United States. The research presented herein analyzed the information collected on the first two years of the project. The proportions of remaining casings and seeds per study zone were compared using the chi-square distribution. Zone 1 had the least pipes lost while Zone 4 had the most (p < 0.05). Forty-three percent of the seeds in Zone 1 remained in the casing, while 26% remained in Zone 2 (p = 0.03). Median growth rates of seeds per study zone showed that Zone 1 had the highest median growth rates. Survival analysis described the survival experience of the seeds, and differences in survival probabilities were compared with the log-rank test. Zone 1 seeds had a better survival experience compared to Zones 2, 3 and 4 (p < 0.0001). Survival probabilities for being free of spots were over 60% during the whole study period. No significant differences were observed in the survival experience with the use-or-no use of casing extensions (p = 0.40), and the use-or-no use of nursed seeds (p = 0.26). Differences in survival probabilities might be attributed to variations in wave energy, depth or substrate conditions. This hypothesis will be evaluated in the second phase of the study. PMID:10730307

  10. Overwintering Survival of Drosophila suzukii (Diptera: Drosophilidae) and the Effect of Food on Adult Survival in California's San Joaquin Valley.

    PubMed

    Kaçar, Gülay; Wang, Xin-Geng; Stewart, Thomas J; Daane, Kent M

    2016-08-01

    The overwintering survival and development of Drosophila suzukii Matsumura were investigated in California's San Joaquin Valley. Drosophila suzukii were exposed to overwintering conditions in cages hung in a citrus orchard, and the pupae were buried in the soil. Eggs exposed from late November to January did not survive; a low percentage (<3%) of larvae and pupae developed into adults. Survival of pupae was significantly higher when buried in the soil than on the citrus tree. From late January to March, all life stages developed into adults and overwintered adult female D. suzukii produced eggs when provided with 10% honey-water and sliced oranges. Adult survival varied among fruit juice provision treatments and overwintering exposure periods, ranging from 3.4 ± 0.9 d (water) to 44.1 ± 3.0 d (10% honey-water). Fruit juices of apple, cherry, grape, orange, and pomegranate were tested as adult food sources; results showed that adult female and male D. suzukii lived only 2 d with water only, whereas adults survived from 14.2 to 34.8 d with fruit juice treatments and the 10% honey-water control. An unexpected event was the oviposition and immature development of D. suzukii with the fruit juice. In a follow-up laboratory trial, when 10% honey-water or orange juice were provided along with an artificial diet for oviposition and immature development, female D. suzukii survived for 21.6 ± 2.4 or 21.6 ± 1.5 d, and produced 106.8 ± 14.1 or 98.5 ± 13.1 offspring, respectively. We discuss factors potentially influencing overwintering survival of D. suzukii. PMID:26654917

  11. Adult survival and population growth rate in Colorado big brown bats (Eptesicus fuscus)

    USGS Publications Warehouse

    O'Shea, T.J.; Ellison, L.E.; Stanley, T.R.

    2011-01-01

    We studied adult survival and population growth at multiple maternity colonies of big brown bats (Eptesicus fuscus) in Fort Collins, Colorado. We investigated hypotheses about survival using information-theoretic methods and mark-recapture analyses based on passive detection of adult females tagged with passive integrated transponders. We constructed a 3-stage life-history matrix model to estimate population growth rate (??) and assessed the relative importance of adult survival and other life-history parameters to population growth through elasticity and sensitivity analysis. Annual adult survival at 5 maternity colonies monitored from 2001 to 2005 was estimated at 0.79 (95% confidence interval [95% CI] = 0.77-0.82). Adult survival varied by year and roost, with low survival during an extreme drought year, a finding with negative implications for bat populations because of the likelihood of increasing drought in western North America due to global climate change. Adult survival during winter was higher than in summer, and mean life expectancies calculated from survival estimates were lower than maximum longevity records. We modeled adult survival with recruitment parameter estimates from the same population. The study population was growing (?? = 1.096; 95% CI = 1.057-1.135). Adult survival was the most important demographic parameter for population growth. Growth clearly had the highest elasticity to adult survival, followed by juvenile survival and adult fecundity (approximately equivalent in rank). Elasticity was lowest for fecundity of yearlings. The relative importances of the various life-history parameters for population growth rate are similar to those of large mammals. ?? 2011 American Society of Mammalogists.

  12. Sugar administration to newly emerged Aedes albopictus males increases their survival probability and mating performance.

    PubMed

    Bellini, Romeo; Puggioli, Arianna; Balestrino, Fabrizio; Brunelli, Paolo; Medici, Anna; Urbanelli, Sandra; Carrieri, Marco

    2014-04-01

    Aedes albopictus male survival in laboratory cages is no more than 4-5 days when kept without any access to sugar indicating their need to feed on a sugar source soon after emergence. We therefore developed a device to administer energetic substances to newly emerged males when released as pupae as part of a sterile insect technique (SIT) programme, made with a polyurethane sponge 4 cm thick and perforated with holes 2 cm in diameter. The sponge was imbibed with the required sugar solution and due to its high retention capacity the sugar solution was available for males to feed for at least 48 h. When evaluated in lab cages, comparing adults emerged from the device with sugar solution vs the device with water only (as negative control), about half of the males tested positive for fructose using the Van Handel anthrone test, compared to none of males in the control cage. We then tested the tool in semi-field and in field conditions with different sugar concentrations (10%, 15%, and 20%) and compared results to the controls fed with water only. Males were recaptured by a battery operated manual aspirator at 24 and 48 h after pupae release. Rather high share 10-25% of captured males tested positive for fructose in recollections in the vicinity of the control stations, while in the vicinity of the sugar stations around 40-55% of males were positive, though variability between replicates was large. The sugar positive males in the control test may have been released males that had access to natural sugar sources found close to the release station and/or wild males present in the environment. Only a slight increase in the proportion of positive males was obtained by increasing the sugar concentration in the feeding device from 10% to 20%. Surprisingly, modification of the device to add a black plastic inverted funnel above the container reduced rather than increased the proportion of fructose positive males collected around the station. No evidence of difference in the

  13. Adaptive Memory: Survival Processing Increases Both True and False Memory in Adults and Children

    ERIC Educational Resources Information Center

    Otgaar, Henry; Smeets, Tom

    2010-01-01

    Research has shown that processing information in a survival context can enhance the information's memorability. The current study examined whether survival processing can also decrease the susceptibility to false memories and whether the survival advantage can be found in children. In Experiment 1, adults rated semantically related words in a…

  14. Gambling, Delay, and Probability Discounting in Adults With and Without ADHD.

    PubMed

    Dai, Zhijie; Harrow, Sarah-Eve; Song, Xianwen; Rucklidge, Julia; Grace, Randolph

    2013-08-21

    Objective: We investigated the relationship between impulsivity, as measured by delay and probability discounting, and gambling-related cognitions and behavior in adults with and without ADHD. Method: Adults who met Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) diagnostic criteria for ADHD (n = 31) and controls (n = 29) were recruited from the community. All completed an interview that included an assessment of psychiatric disorders, gambling questionnaires, and simulated gambling, delay, and probability discounting tasks. Results: The ADHD group was more likely to meet the criteria for problem gambling and was more impulsive than controls based on a composite discounting measure. ADHD symptoms were correlated with gambling-related cognitions and behavior. Probability, but not delay discounting, explained significant variance in gambling-related measures after controlling for ADHD symptoms. Discussion: Results confirm an association between adult ADHD and gambling, and suggest that the facets of impulsivity related to risk proneness may be an independent risk factor for problem gambling in this population. (J. of Att. Dis. XXXX; XX(X) 1-XX). PMID:23966350

  15. Spin Dependence in the Survival Probability of Metastable He (23S) Atoms during the Scattering from Ferromagnetic Surfaces

    NASA Astrophysics Data System (ADS)

    Kurahashi, M.; Suzuki, T.; Ju, X.; Yamauchi, Y.

    2003-12-01

    The use of a spin-polarized metastable helium (He*) atom beam has demonstrated that the survival probability (SP) of He* during the scattering from ferromagnetic surfaces depends on the electron spin of He*. The spin asymmetry in the SP of He* scattered from a clean Fe/Cu(100) surface changed its polarity with H2O adsorption. We argue that the reversal is caused by the change in the spin polarization of the surface electronic states at around the Fermi level.

  16. Limitation of Inverse Probability-of-Censoring Weights in Estimating Survival in the Presence of Strong Selection Bias

    PubMed Central

    Howe, Chanelle J.; Cole, Stephen R.; Chmiel, Joan S.; Muñoz, Alvaro

    2011-01-01

    In time-to-event analyses, artificial censoring with correction for induced selection bias using inverse probability-of-censoring weights can be used to 1) examine the natural history of a disease after effective interventions are widely available, 2) correct bias due to noncompliance with fixed or dynamic treatment regimens, and 3) estimate survival in the presence of competing risks. Artificial censoring entails censoring participants when they meet a predefined study criterion, such as exposure to an intervention, failure to comply, or the occurrence of a competing outcome. Inverse probability-of-censoring weights use measured common predictors of the artificial censoring mechanism and the outcome of interest to determine what the survival experience of the artificially censored participants would be had they never been exposed to the intervention, complied with their treatment regimen, or not developed the competing outcome. Even if all common predictors are appropriately measured and taken into account, in the context of small sample size and strong selection bias, inverse probability-of-censoring weights could fail because of violations in assumptions necessary to correct selection bias. The authors used an example from the Multicenter AIDS Cohort Study, 1984–2008, regarding estimation of long-term acquired immunodeficiency syndrome-free survival to demonstrate the impact of violations in necessary assumptions. Approaches to improve correction methods are discussed. PMID:21289029

  17. Predictors of the new criteria for probable PTSD among older adults.

    PubMed

    Palgi, Yuval

    2015-12-30

    The definition of post-traumatic stress disorder (PTSD) changed in the fifth edition of the Diagnostic and Statistical Manual (DSM-5) and it is yet unclear how these changes affect the diagnosis of PTSD among older adults. The present study examined the contribution of demographic characteristics, functioning status, health related factors, as well as exposure to rocket attacks to prediction of probable PTSD in older adults. Three-hundred and thirty-nine community-dwelling adults (age range 50-90; M=65.44, SD=9.77) were sampled through random dialing to Jewish residents in the south of Israel. Participants completed a phone-questionnaire that collected background information and reports of relevant symptoms. Analyses showed that self-rated health, incidence of depression episodes, and exposure to rocket attacks predicted the DSM-5 definition of PTSD as well as the subscale of negative alternations in cognition and mood. The current study delineates the unique set of predictors of probable PTSD in older adults, with an emphasis on negative alternations in cognition and mood. Greater attention to unique predictors of PTSD in the second half of life is called for. PMID:26586141

  18. A method for estimating fall adult sex ratios from production and survival data

    USGS Publications Warehouse

    Wight, H.M.; Heath, R.G.; Geis, A.D.

    1965-01-01

    This paper presents a method of utilizing data relating to the production and survival of a bird population to estimate a basic fall adult sex ratio. This basic adult sex ratio is an average value derived from average production and survival rates. It is an estimate of the average sex ratio about which the fall adult ratios will fluctuate according to annual variations in production and survival. The basic fall adult sex ratio has been calculated as an asymptotic value which is the limit of an infinite series wherein average population characteristics are used as constants. Graphs are provided that allow the determination of basic sex ratios from production and survival data of a population. Where the respective asymptote has been determined, it may be possible to estimate various production and survival rates by use of variations of the formula for estimating the asymptote.

  19. One step forward: contrasting the effects of Toe clipping and PIT tagging on frog survival and recapture probability

    PubMed Central

    Guimarães, Murilo; Corrêa, Décio T; Filho, Sérgio S; Oliveira, Thiago A L; Doherty, Paul F; Sawaya, Ricardo J

    2014-01-01

    Amphibians have been declining worldwide and the comprehension of the threats that they face could be improved by using mark–recapture models to estimate vital rates of natural populations. Recently, the consequences of marking amphibians have been under discussion and the effects of toe clipping on survival are debatable, although it is still the most common technique for individually identifying amphibians. The passive integrated transponder (PIT tag) is an alternative technique, but comparisons among marking techniques in free-ranging populations are still lacking. We compared these two marking techniques using mark–recapture models to estimate apparent survival and recapture probability of a neotropical population of the blacksmith tree frog, Hypsiboas faber. We tested the effects of marking technique and number of toe pads removed while controlling for sex. Survival was similar among groups, although slightly decreased from individuals with one toe pad removed, to individuals with two and three toe pads removed, and finally to PIT-tagged individuals. No sex differences were detected. Recapture probability slightly increased with the number of toe pads removed and was the lowest for PIT-tagged individuals. Sex was an important predictor for recapture probability, with males being nearly five times more likely to be recaptured. Potential negative effects of both techniques may include reduced locomotion and high stress levels. We recommend the use of covariates in models to better understand the effects of marking techniques on frogs. Accounting for the effect of the technique on the results should be considered, because most techniques may reduce survival. Based on our results, but also on logistical and cost issues associated with PIT tagging, we suggest the use of toe clipping with anurans like the blacksmith tree frog. PMID:24834342

  20. SynCAM 1 improves survival of adult-born neurons by accelerating synapse maturation.

    PubMed

    Doengi, Michael; Krupp, Alexander J; Körber, Nils; Stein, Valentin

    2016-03-01

    The survival of adult-born dentate gyrus granule cells critically depends on their synaptic integration into the existing neuronal network. Excitatory inputs are thought to increase the survival rate of adult born neurons. Therefore, whether enhancing the stability of newly formed excitatory synapses by overexpressing the synaptic cell adhesion molecule SynCAM 1 improves the survival of adult-born neurons was tested. Here it is shown that overexpression of SynCAM 1 improves survival of adult-born neurons, but has no effect on the proliferation rate of precursor cells. As expected, overexpression of SynCAM 1 increased the synapse density in adult-born granule neurons. While adult-born granule neurons have very few functional synapses 15 days after birth, it was found that at this age adult-born neurons in SynCAM 1 overexpressing mice exhibited around three times more excitatory synapses, which were stronger than synapses of adult-born neurons of control littermates. In summary, the data indicated that additional SynCAM 1 accelerated synapse maturation, which improved the stability of newly formed synapses and in turn increased the likelihood of survival of adult-born neurons. © 2015 Wiley Periodicals, Inc. PMID:26332750

  1. Intraseasonal variation in survival and probable causes of mortality in greater sage-grouse Centrocercus urophasianus

    USGS Publications Warehouse

    Blomberg, Erik J.; Gibson, Daniel; Sedinger, James S.; Casazza, Michael L.; Coates, Peter S.

    2013-01-01

    The mortality process is a key component of avian population dynamics, and understanding factors that affect mortality is central to grouse conservation. Populations of greater sage-grouse Centrocercus urophasianus have declined across their range in western North America. We studied cause-specific mortality of radio-marked sage-grouse in Eureka County, Nevada, USA, during two seasons, nesting (2008-2012) and fall (2008-2010), when survival was known to be lower compared to other times of the year. We used known-fate and cumulative incidence function models to estimate weekly survival rates and cumulative risk of cause-specific mortalities, respectively. These methods allowed us to account for temporal variation in sample size and staggered entry of marked individuals into the sample to obtain robust estimates of survival and cause-specific mortality. We monitored 376 individual sage-grouse during the course of our study, and investigated 87 deaths. Predation was the major source of mortality, and accounted for 90% of all mortalities during our study. During the nesting season (1 April - 31 May), the cumulative risk of predation by raptors (0.10; 95% CI: 0.05-0.16) and mammals (0.08; 95% CI: 0.03-013) was relatively equal. In the fall (15 August - 31 October), the cumulative risk of mammal predation was greater (M(mam) = 0.12; 95% CI: 0.04-0.19) than either predation by raptors (M(rap) = 0.05; 95% CI: 0.00-0.10) or hunting harvest (M(hunt) = 0.02; 95% CI: 0.0-0.06). During both seasons, we observed relatively few additional sources of mortality (e.g. collision) and observed no evidence of disease-related mortality (e.g. West Nile Virus). In general, we found little evidence for intraseasonal temporal variation in survival, suggesting that the nesting and fall seasons represent biologically meaningful time intervals with respect to sage-grouse survival.

  2. Geographic Variation in Adult Survival and Reproductive Tactics of the Mosquito Aedes albopictus

    PubMed Central

    LEISNHAM, P. T.; SALA, L. M.; JULIANO, S. A.

    2008-01-01

    Climate differences across latitude can result in seasonal constraints and selection on life history characters. Since Aedes albopictus (Skuse) invaded North America in the mid-1980s, it has spread across a range of ≈14° latitude and populations in the north experience complete adult mortality due to cold winter temperatures that are absent in the south. Life table experiments were conducted to test for differences in the adult survival and reproductive schedules of Ae. albopictus females from two populations from the northern (Bloomington, IN [BL] and Manassas, VA [VA]; ≈39° N) and southern (Tampa, FL and Fort Myers, FL; ≈27–28° N) extremes of the species distribution in North America. Regardless of population origin, age-specific hazard rate increased with reproductive output and decreased with number of bloodmeals. Larger females took fewer bloodmeals, and they had greater hazard rates than did smaller females. There were no consistent differences between northern versus southern populations in resource allocation between reproduction and maintenance, reproduction over time, and reproductive investment among offspring, suggesting that latitudinal variation in climate is probably not a main selective factor impinging on adult mortality and reproductive schedules. One possible effect of climate on geographic differences in life history was detected. BL had lower survivorship, lower lifetime reproductive output, and lower adult reproductive rate than did all other populations. This result may be an indirect result of lower egg survivorship due to the severity of winter in BL compared with other populations, including VA at approximately the same latitude. Such a scenario may make the BL population more prone to extinction, irregularly recolonized from more favorable sites, and thus more susceptible to founder effects, genetic drift, and inbreeding, resulting in lower mean values of fitness-related traits. PMID:18402136

  3. Survival improvements in adolescents and young adults after myeloablative allogeneic transplantation for acute lymphoblastic leukemia.

    PubMed

    Wood, William A; Lee, Stephanie J; Brazauskas, Ruta; Wang, Zhiwei; Aljurf, Mahmoud D; Ballen, Karen K; Buchbinder, David K; Dehn, Jason; Freytes, Cesar O; Lazarus, Hillard M; Lemaistre, Charles F; Mehta, Paulette; Szwajcer, David; Joffe, Steven; Majhail, Navneet S

    2014-06-01

    Adolescents and young adults (AYAs, ages 15 to 40 years) with cancer have not experienced survival improvements to the same extent as younger and older patients. We compared changes in survival after myeloablative allogeneic hematopoietic cell transplantation (HCT) for acute lymphoblastic leukemia (ALL) among children (n = 981), AYAs (n = 1218), and older adults (n = 469) who underwent transplantation over 3 time periods: 1990 to 1995, 1996 to 2001, and 2002 to 2007. Five-year survival varied inversely with age group. Survival improved over time in AYAs and paralleled that seen in children; however, overall survival did not change over time for older adults. Survival improvements were primarily related to lower rates of early treatment-related mortality in the most recent era. For all cohorts, relapse rates did not change over time. A subset of 222 AYAs between the ages of 15 and 25 at 46 pediatric or 49 adult centers were also analyzed to describe differences by center type. In this subgroup, there were differences in transplantation practices among pediatric and adult centers, although HCT outcomes did not differ by center type. Survival for AYAs undergoing myeloablative allogeneic HCT for ALL improved at a similar rate as survival for children. PMID:24607554

  4. More than words: Adults learn probabilities over categories and relationships between them

    PubMed Central

    Hudson Kam, Carla L.

    2009-01-01

    This study examines whether human learners can acquire statistics over abstract categories and their relationships to each other. Adult learners were exposed to miniature artificial languages containing variation in the ordering of the Subject, Object, and Verb constituents. Different orders (e.g. SOV, VSO) occurred in the input with different frequencies, but the occurrence of one order versus another was not predictable. Importantly, the language was constructed such that participants could only match the overall input probabilities if they were tracking statistics over abstract categories, not over individual words. At test, participants reproduced the probabilities present in the input with a high degree of accuracy. Closer examination revealed that learner’s were matching the probabilities associated with individual verbs rather than the category as a whole. However, individual nouns had no impact on word orders produced. Thus, participants learned the probabilities of a particular ordering of the abstract grammatical categories Subject and Object associated with each verb. Results suggest that statistical learning mechanisms are capable of tracking relationships between abstract linguistic categories in addition to individual items. PMID:20161375

  5. MORBIDITY AND SURVIVAL PROBABILITY IN BURN PATIENTS IN MODERN BURN CARE

    PubMed Central

    Jeschke, Marc G.; Pinto, Ruxandra; Kraft, Robert; Nathens, Avery B.; Finnerty, Celeste C.; Gamelli, Richard L.; Gibran, Nicole S.; Klein, Matthew B.; Arnoldo, Brett D.; Tompkins, Ronald G.; Herndon, David N.

    2014-01-01

    Objective Characterizing burn sizes that are associated with an increased risk of mortality and morbidity is critical because it would allow identifying patients who might derive the greatest benefit from individualized, experimental, or innovative therapies. Although scores have been established to predict mortality, few data addressing other outcomes exist. The objective of this study was to determine burn sizes that are associated with increased mortality and morbidity after burn. Design and Patients Burn patients were prospectively enrolled as part of the multicenter prospective cohort study, Inflammation and the Host Response to Injury Glue Grant, with the following inclusion criteria: 0–99 years of age, admission within 96 hours after injury, and >20% total body surface area burns requiring at least one surgical intervention. Setting Six major burn centers in North America. Measurements and Main Results Burn size cutoff values were determined for mortality, burn wound infection (at least two infections), sepsis (as defined by ABA sepsis criteria), pneumonia, acute respiratory distress syndrome, and multiple organ failure (DENVER2 score >3) for both children (<16 years) and adults (16–65 years). Five-hundred seventy-three patients were enrolled, of which 226 patients were children. Twenty-three patients were older than 65 years and were excluded from the cutoff analysis. In children, the cutoff burn size for mortality, sepsis, infection, and multiple organ failure was approximately 60% total body surface area burned. In adults, the cutoff for these outcomes was lower, at approximately 40% total body surface area burned. Conclusions In the modern burn care setting, adults with over 40% total body surface area burned and children with over 60% total body surface area burned are at high risk for morbidity and mortality, even in highly specialized centers. PMID:25559438

  6. Comparison of survival of adolescents and young adults with hematologic malignancies in Osaka, Japan.

    PubMed

    Nakata-Yamada, Kayo; Inoue, Masami; Ioka, Akiko; Ito, Yuri; Tabuchi, Takahiro; Miyashiro, Isao; Masaie, Hiroaki; Ishikawa, Jun; Hino, Masayuki; Tsukuma, Hideaki

    2016-06-01

    The survival gap between adolescents and young adults (AYAs) with hematological malignancies persists in many countries. To determine to what extent it does in Japan, we investigated survival and treatment regimens in 211 Japanese AYAs (15-29 years) in the Osaka Cancer Registry diagnosed during 2001-2005 with hematological malignancies, and compared adolescents (15-19 years) with young adults (20-29 years). AYAs with acute lymphoblastic leukemia (ALL) had a poor 5-year survival (44%), particularly young adults (29% vs. 64% in adolescents, p = 0.01). Additional investigation for patients with ALL revealed that only 19% of young adults were treated with pediatric treatment regimens compared with 45% of adolescents (p = 0.05). Our data indicate that we need to focus on young adults with ALL and to consider establishing appropriate cancer care system and guidelines for them in Japan. PMID:26695739

  7. Interaction Cross Sections and Survival Probabilities for Proposed Solar System Member Planet Nine

    NASA Astrophysics Data System (ADS)

    Adams, Fred C.; Li, Gongjie

    2016-05-01

    Motivated by the report of a possible new planetary member of the Solar System, this work calculates cross sections for interactions between passing stars and this proposed Planet Nine. Evidence for the new planet is provided by the orbital alignment of Kuiper Belt objects, and other Solar System properties, which suggest a Neptune-mass object on an eccentric orbit with semimajor axis \\anine = 400 - 1500 AU. With such a wide orbit, Planet Nine has a large interaction cross section, and is susceptible to disruption by passing stars. Using a large ensemble of numerical simulations, and Monte Carlo sampling, we calculate the cross sections for different classes of orbit-altering events: [A] scattering the planet into its proposed orbit from a smaller orbit, [B] ejecting it from the Solar System from its current orbit, [C] capturing the planet from another system, and [D] capturing a free-floating planet. Results are presented for a range of orbital elements with planetary mass of 10 Earth masses. Removing Planet Nine from the Solar System is the most likely outcome. Specifically, we obtain ejection cross sections σ=4.2×10^6 AU^2 (4.3×10^4 AU^2) for environments corresponding to the birth cluster (field). With these cross sections, Planet Nine is likely to be ejected if the Sun resides within its birth cluster longer than Δ{t} > 100 Myr. The probability of ejecting Planet Nine due to passing field stars is of order 1 percent over the age of the Sun. Probabilities for producing the inferred Planet Nine orbit are comparable (a few percent).

  8. BURN SIZE AND SURVIVAL PROBABILITY IN PEDIATRIC PATIENTS IN MODERN BURN CARE

    PubMed Central

    Kraft, Robert; Herndon, David N; Al-Mousawi, Ahmed M; Williams, Felicia N; Finnerty, Celeste C; Jeschke, Marc G

    2012-01-01

    Background Patient survival following severe burn injury is largely determined by burn size. Modern developments in burn care have tremendously improved survival and outcomes. However, no large analysis on outcomes in pediatric burn patients with current treatment regimen exists. This study was designed to identify the burn size presently associated with significant increases in morbidity and mortality in pediatric burn patients. Methods Single center prospective observational cohort study utilizing the clinical data of severely burned pediatric patients admitted between 1998 and 2009. This study included 952 severely burned pediatric patients with burns over at least 30% of their total body surface area (TBSA). Patients were stratified by burn size in 10% increments, ranging from 30 to 100%, with a secondary assignment made according to the outcome of a receiver operating characteristic (ROC) analysis. Statistical analysis was performed using Student’s t-test, χ2 test, logistic regression and ROC analysis, as appropriate, with significance set at p<0.05. Findings All groups were comparable in age (age in years: 30–39: 6.1±5.1, 40–49: 7.1±5.2, 50–59: 7.6±5.1, 60–69: 7.2±5.1, 70–79: 8.3±5.9, 80–89: 8.4±5.6, 90–100: 9.6±5.4), and gender distribution (male: 30–39: 68%, 40–49: 64%, 50–59: 65%, 60–69: 59%, 70–79: 71%, 80–89: 62%, 90–100: 82%). Mortality (30–39: 3%, 40–49: 3%, 50–59: 7%, 60–69: 16%, 70–79: 22%, 80–89: 35%, 90–100: 55%), multi-organ failure (30–39: 6%, 40–49: 6%, 50–59: 12%, 60–69: 27%, 70–79: 29%, 80–89: 44%, 90–100: 45%), and sepsis (30–39: 2%, 40–49: 5%, 50–59: 6%, 60–69: 15%, 70–79: 13%, 80–89: 22%, 90–100: 26%), increased significantly (p<0.001) among the groups and at a threshold of 62% TBSA. Comparison of patients with burns larger than 62% with those smaller showed significant differences in inflammatory (Cytokines), acute phase (CRP) and hypermetabolic responses (REE

  9. Effects of yearling, juvenile and adult survival on reef manta ray (Manta alfredi) demography

    PubMed Central

    van der Ouderaa, Isabelle B.C.; Tibiriçá, Yara

    2016-01-01

    Background The trade in manta ray gill plates has considerably increased over the last two decades. The resulting increases in ray mortality, in addition to mortality caused by by-catch, has caused many ray populations to decrease in size. The aim of this study was to ascertain how yearling and juvenile growth and survival, and adult survival and reproduction affect reef manta ray (Manta alfredi) population change, to increase our understanding of manta ray demography and thereby improve conservation research and measures for these fish. Methods We developed a population projection model for reef manta rays, and used published life history data on yearling and juvenile growth and adult reproduction to parameterise the model. Because little is known about reef manta ray yearling and juvenile survival, we conducted our analyses using a range of plausible survival rate values for yearlings, juveniles and adults. Results The model accurately captured observed variation in population growth rate, lifetime reproductive success and cohort generation time in different reef manta ray populations. Our demographic analyses revealed a range of population consequences in response to variation in demographic rates. For example, an increase in yearling or adult survival rates always elicited greater responses in population growth rate, lifetime reproductive success and cohort generation time than the same increase in juvenile survival rate. The population growth rate increased linearly, but lifetime reproductive success and cohort generation time increased at an accelerating rate with increasing yearling or adult survival rates. Hence, even a small increase in survival rate could increase lifetime reproductive success by one pup, and cohort generation time by several years. Elasticity analyses revealed that, depending on survival rate values of all life stages, the population growth rate is either most sensitive to changes in the rate with which juveniles survive but stay

  10. Equal nonbreeding period survival in adults and juveniles of a long-distant migrant bird

    PubMed Central

    Grüebler, Martin U; Korner-Nievergelt, Fränzi; Naef-Daenzer, Beat

    2014-01-01

    In migrant birds, survival estimates for the different life-history stages between fledging and first breeding are scarce. First-year survival is shown to be strongly reduced compared with annual survival of adult birds. However, it remains unclear whether the main bottleneck in juvenile long-distant migrants occurs in the postfledging period within the breeding ranges or en route. Quantifying survival rates during different life-history stages and during different periods of the migration cycle is crucial to understand forces driving the evolution of optimal life histories in migrant birds. Here, we estimate survival rates of adult and juvenile barn swallows (Hirundo rusticaL.) in the breeding and nonbreeding areas using a population model integrating survival estimates in the breeding ranges based on a large radio-telemetry data set and published estimates of demographic parameters from large-scale population-monitoring projects across Switzerland. Input parameters included the country-wide population trend, annual productivity estimates of the double-brooded species, and year-to-year survival corrected for breeding dispersal. Juvenile survival in the 3-week postfledging period was low (S = 0.32; SE = 0.05), whereas in the rest of the annual cycle survival estimates of adults and juveniles were similarly high (S > 0.957). Thus, the postfledging period was the main survival bottleneck, revealing the striking result that nonbreeding period mortality (including migration) is not higher for juveniles than for adult birds. Therefore, focusing future research on sources of variation in postfledging mortality can provide new insights into determinants of population dynamics and life-history evolution of migrant birds. PMID:24683458

  11. Precambrian animal life: probable developmental and adult cnidarian forms from Southwest China

    NASA Technical Reports Server (NTRS)

    Chen, Jun-Yuan; Oliveri, Paola; Gao, Feng; Dornbos, Stephen Q.; Li, Chia-Wei; Bottjer, David J.; Davidson, Eric H.

    2002-01-01

    The evolutionary divergence of cnidarian and bilaterian lineages from their remote metazoan ancestor occurred at an unknown depth in time before the Cambrian, since crown group representatives of each are found in Lower Cambrian fossil assemblages. We report here a variety of putative embryonic, larval, and adult microfossils deriving from Precambrian phosphorite deposits of Southwest China, which may predate the Cambrian radiation by 25-45 million years. These are most probably of cnidarian affinity. Large numbers of fossilized early planula-like larvae were observed under the microscope in sections. Though several forms are represented, the majority display remarkable conformity, which is inconsistent with the alternative that they are artifactual mineral inclusions. Some of these fossils are preserved in such high resolution that individual cells can be discerned. We confirm in detail an earlier report of the presence in the same deposits of tabulates, an extinct crown group anthozoan form. Other sections reveal structures that most closely resemble sections of basal modern corals. A large number of fossils similar to modern hydrozoan gastrulae were also observed. These again displayed great morphological consistency. Though only a single example is available, a microscopic animal remarkably similar to a modern adult hydrozoan is also presented. Taken together, the new observations reported in this paper indicate the existence of a diverse and already differentiated cnidarian fauna, long before the Cambrian evolutionary event. It follows that at least stem group bilaterians must also have been present at this time.

  12. Survival rates of adult lake trout in northwestern Lake Michigan, 1983-1993

    USGS Publications Warehouse

    Fabrizio, Mary C.; Holey, Mark E.; McKee, Patrick C.; Toneys, Michael L.

    1997-01-01

    The restoration of lake trout Salvelinus namaycush in Lake Michigan has been an elusive goal of resource management agencies in the Great Lakes region. In this study, we estimated annual survival rates of adult lake trout from an area in northwestern Lake Michigan known as the Clay Banks refuge. We tagged and recaptured fish with gill nets during the fall spawning season (N = 12,175; 1983–1989 and 1991–1993) and with pound nets in the spring (N = 52,035; 1984–1990 and 1992–1993). We fit Cormack–Jolly–Seber models to the two sets of data. We had insufficient data to analyze annual differences in survival rates of fall-tagged fish, but we were able to estimate an overall annual survival rate of 0.67. Annual survival rates of spring-tagged fish varied between 0.53 and 0.88 and increased after 1987–1988. In addition to the mark–recapture studies, we analyzed catch rates of lake trout from gill-net and pound-net surveys to estimate survival rates using catch curve analyses; these annual rates were generally lower than those estimated from mark–recapture analyses of tagged fish. However, survival rates of lake trout from the Clay Banks refuge appeared to meet the minimum rate believed necessary for restoration of this species in Lake Michigan. Furthermore, adult survival rates have been increasing in recent years, and lake trout restoration in Lake Michigan is not hampered by low survival of adult fish. We hypothesize that the recent decrease in abundance of adult lake trout is primarily due to decreases in survival rates of lake trout younger than 6 years.

  13. Model Assembly for Estimating Cell Surviving Fraction for Both Targeted and Nontargeted Effects Based on Microdosimetric Probability Densities

    PubMed Central

    Sato, Tatsuhiko; Hamada, Nobuyuki

    2014-01-01

    We here propose a new model assembly for estimating the surviving fraction of cells irradiated with various types of ionizing radiation, considering both targeted and nontargeted effects in the same framework. The probability densities of specific energies in two scales, which are the cell nucleus and its substructure called a domain, were employed as the physical index for characterizing the radiation fields. In the model assembly, our previously established double stochastic microdosimetric kinetic (DSMK) model was used to express the targeted effect, whereas a newly developed model was used to express the nontargeted effect. The radioresistance caused by overexpression of anti-apoptotic protein Bcl-2 known to frequently occur in human cancer was also considered by introducing the concept of the adaptive response in the DSMK model. The accuracy of the model assembly was examined by comparing the computationally and experimentally determined surviving fraction of Bcl-2 cells (Bcl-2 overexpressing HeLa cells) and Neo cells (neomycin resistant gene-expressing HeLa cells) irradiated with microbeam or broadbeam of energetic heavy ions, as well as the WI-38 normal human fibroblasts irradiated with X-ray microbeam. The model assembly reproduced very well the experimentally determined surviving fraction over a wide range of dose and linear energy transfer (LET) values. Our newly established model assembly will be worth being incorporated into treatment planning systems for heavy-ion therapy, brachytherapy, and boron neutron capture therapy, given critical roles of the frequent Bcl-2 overexpression and the nontargeted effect in estimating therapeutic outcomes and harmful effects of such advanced therapeutic modalities. PMID:25426641

  14. Model assembly for estimating cell surviving fraction for both targeted and nontargeted effects based on microdosimetric probability densities.

    PubMed

    Sato, Tatsuhiko; Hamada, Nobuyuki

    2014-01-01

    We here propose a new model assembly for estimating the surviving fraction of cells irradiated with various types of ionizing radiation, considering both targeted and nontargeted effects in the same framework. The probability densities of specific energies in two scales, which are the cell nucleus and its substructure called a domain, were employed as the physical index for characterizing the radiation fields. In the model assembly, our previously established double stochastic microdosimetric kinetic (DSMK) model was used to express the targeted effect, whereas a newly developed model was used to express the nontargeted effect. The radioresistance caused by overexpression of anti-apoptotic protein Bcl-2 known to frequently occur in human cancer was also considered by introducing the concept of the adaptive response in the DSMK model. The accuracy of the model assembly was examined by comparing the computationally and experimentally determined surviving fraction of Bcl-2 cells (Bcl-2 overexpressing HeLa cells) and Neo cells (neomycin resistant gene-expressing HeLa cells) irradiated with microbeam or broadbeam of energetic heavy ions, as well as the WI-38 normal human fibroblasts irradiated with X-ray microbeam. The model assembly reproduced very well the experimentally determined surviving fraction over a wide range of dose and linear energy transfer (LET) values. Our newly established model assembly will be worth being incorporated into treatment planning systems for heavy-ion therapy, brachytherapy, and boron neutron capture therapy, given critical roles of the frequent Bcl-2 overexpression and the nontargeted effect in estimating therapeutic outcomes and harmful effects of such advanced therapeutic modalities. PMID:25426641

  15. How Long Do the Dead Survive on the Road? Carcass Persistence Probability and Implications for Road-Kill Monitoring Surveys

    PubMed Central

    Santos, Sara M.; Carvalho, Filipe; Mira, António

    2011-01-01

    Background Road mortality is probably the best-known and visible impact of roads upon wildlife. Although several factors influence road-kill counts, carcass persistence time is considered the most important determinant underlying underestimates of road mortality. The present study aims to describe and model carcass persistence variability on the road for different taxonomic groups under different environmental conditions throughout the year; and also to assess the effect of sampling frequency on the relative variation in road-kill estimates registered within a survey. Methodology/Principal Findings Daily surveys of road-killed vertebrates were conducted over one year along four road sections with different traffic volumes. Survival analysis was then used to i) describe carcass persistence timings for overall and for specific animal groups; ii) assess optimal sampling designs according to research objectives; and iii) model the influence of road, animal and weather factors on carcass persistence probabilities. Most animal carcasses persisted on the road for the first day only, with some groups disappearing at very high rates. The advisable periodicity of road monitoring that minimizes bias in road mortality estimates is daily monitoring for bats (in the morning) and lizards (in the afternoon), daily monitoring for toads, small birds, small mammals, snakes, salamanders, and lagomorphs; 1 day-interval (alternate days) for large birds, birds of prey, hedgehogs, and freshwater turtles; and 2 day-interval for carnivores. Multiple factors influenced the persistence probabilities of vertebrate carcasses on the road. Overall, the persistence was much lower for small animals, on roads with lower traffic volumes, for carcasses located on road lanes, and during humid conditions and high temperatures during the wet season and dry seasons, respectively. Conclusion/Significance The guidance given here on monitoring frequencies is particularly relevant to provide conservation and

  16. GABA-CREB signalling regulates maturation and survival of newly generated neurons in the adult hippocampus

    PubMed Central

    Jagasia, Ravi; Steib, Kathrin; Englberger, Elisabeth; Herold, Sabine; Faus-Kessler, Theresa; Saxe, Michael; Gage, Fred H.; Song, Hongjun; Lie, D. Chichung

    2009-01-01

    Survival and integration of new neurons in the hippocampal circuit are rate-limiting steps in adult hippocampal neurogenesis. Neuronal network activity is a major regulator of these processes, yet little is known about the respective downstream signalling pathways. Here, we investigate the role of CREB signalling in adult hippocampal neurogenesis. CREB is activated in new granule neurons during a distinct developmental period. Loss of CREB function in a cell-autonomous fashion impairs dendritic development, decreases the expression of the neurogenic transcription factor NeuroD and of the neuronal microtubule associated protein, DCX, and compromises the survival of newborn neurons. In addition, GABA-mediated excitation regulates CREB activation at early developmental stages. Importantly, developmental defects following loss of GABA-mediated excitation can be compensated by enhanced CREB signalling. These results indicate that CREB signalling is a central pathway in adult hippocampal neurogenesis, regulating the development and survival of new hippocampal neurons downstream of GABA-mediated excitation. PMID:19553437

  17. A TRPV Channel Modulates C. elegans Neurosecretion, Larval Starvation Survival, and Adult Lifespan

    PubMed Central

    Lee, Brian H.; Ashrafi, Kaveh

    2008-01-01

    For most organisms, food is only intermittently available; therefore, molecular mechanisms that couple sensation of nutrient availability to growth and development are critical for survival. These mechanisms, however, remain poorly defined. In the absence of nutrients, newly hatched first larval (L1) stage Caenorhabditis elegans halt development and survive in this state for several weeks. We isolated mutations in unc-31, encoding a calcium-activated regulator of neural dense-core vesicle release, which conferred enhanced starvation survival. This extended survival was reminiscent of that seen in daf-2 insulin-signaling deficient mutants and was ultimately dependent on daf-16, which encodes a FOXO transcription factor whose activity is inhibited by insulin signaling. While insulin signaling modulates metabolism, adult lifespan, and dauer formation, insulin-independent mechanisms that also regulate these processes did not promote starvation survival, indicating that regulation of starvation survival is a distinct program. Cell-specific rescue experiments identified a small subset of primary sensory neurons where unc-31 reconstitution modulated starvation survival, suggesting that these neurons mediate perception of food availability. We found that OCR-2, a transient receptor potential vanilloid (TRPV) channel that localizes to the cilia of this subset of neurons, regulates peptide-hormone secretion and L1 starvation survival. Moreover, inactivation of ocr-2 caused a significant extension in adult lifespan. These findings indicate that TRPV channels, which mediate sensation of diverse noxious, thermal, osmotic, and mechanical stimuli, couple nutrient availability to larval starvation survival and adult lifespan through modulation of neural dense-core vesicle secretion. PMID:18846209

  18. Survival of newly emerged Culex tritaeniorhynchus (Diptera:Culicidae) adults in field cages with or without predators.

    PubMed

    Takagi, M; Sugiyama, A; Maruyama, K

    1996-07-01

    A field experiment was conducted to estimate the survival of Culex tritaeniorhynchus Giles adults before 1st blood feeding under conditions with or without predators in a rice field in central Japan. Adults were counted for 5 d after emerging in cages (2 by 2 and 1.5 m high), which were placed in rice fields during the midseason drying period. Only 10% of the adults survived until day 4 after emergence when exposed to predation, whereas > 60% of the adults survived until day 4 without predation. Lycosidae, hunting spiders, may be an effective predator of Cx. tritaeniorhynchus adults. PMID:8699471

  19. Are Global and Regional Improvements in Life Expectancy and in Child, Adult and Senior Survival Slowing?

    PubMed Central

    Hum, Ryan J.; Verguet, Stéphane; Cheng, Yu-Ling; McGahan, Anita M.; Jha, Prabhat

    2015-01-01

    Improvements in life expectancy have been considerable over the past hundred years. Forecasters have taken to applying historical trends under an assumption of continuing improvements in life expectancy in the future. A linear mixed effects model was used to estimate the trends in global and regional rates of improvements in life expectancy, child, adult, and senior survival, in 166 countries between 1950 and 2010. Global improvements in life expectancy, including both child and adult survival rates, decelerated significantly over the study period. Overall life expectancy gains were estimated to have declined from 5.9 to 4.0 months per year for a mean deceleration of -0.07 months/year2; annual child survival gains declined from 4.4 to 1.6 deaths averted per 1000 for a mean deceleration of -0.06 deaths/1000/year2; adult survival gains were estimated to decline from 4.8 to 3.7 deaths averted per 1000 per year for a mean deceleration of -0.08 deaths/1000/year2. Senior survival gains however increased from 2.4 to 4.2 deaths averted per 1000 per year for an acceleration of 0.03 deaths/1000/year2. Regional variation in the four measures was substantial. The rates of global improvements in life expectancy, child survival, and adult survival have declined since 1950 despite an increase in the rate of improvements among seniors. We postulate that low-cost innovation, related to the last half-century progress in health–primarily devoted to children and middle age, is reaping diminishing returns on its investments. Trends are uneven across regions and measures, which may be due in part to the state of epidemiological transition between countries and regions and disparities in the diffusion of innovation, accessible only in high-income countries where life expectancy is already highest. PMID:25992949

  20. Epidemiology of undiagnosed trichomoniasis in a probability sample of urban young adults.

    PubMed

    Rogers, Susan M; Turner, Charles F; Hobbs, Marcia; Miller, William C; Tan, Sylvia; Roman, Anthony M; Eggleston, Elizabeth; Villarroel, Maria A; Ganapathi, Laxminarayana; Chromy, James R; Erbelding, Emily

    2014-01-01

    T. vaginalis infection (trichomoniasis) is the most common curable sexually transmitted infection (STI) in the U.S. It is associated with increased HIV risk and adverse pregnancy outcomes. Trichomoniasis surveillance data do not exist for either national or local populations. The Monitoring STIs Survey Program (MSSP) collected survey data and specimens which were tested using nucleic acid amplification tests to monitor trichomoniasis and other STIs in 2006-09 among a probability sample of young adults (N = 2,936) in Baltimore, Maryland--an urban area with high rates of reported STIs. The estimated prevalence of trichomoniasis was 7.5% (95% CI 6.3, 9.1) in the overall population and 16.1% (95% CI 13.0, 19.8) among Black women. The overwhelming majority of infected men (98.5%) and women (73.3%) were asymptomatic. Infections were more common in both women (OR = 3.6, 95% CI 1.6, 8.2) and men (OR = 9.0, 95% CI 1.8, 44.3) with concurrent chlamydial infection. Trichomoniasis did not vary significantly by age for either men or women. Women with two or more partners in the past year and women with a history of personal or partner incarceration were more likely to have an infection. Overall, these results suggest that routine T vaginalis screening in populations at elevated risk of infection should be considered. PMID:24626058

  1. Intra-annual patterns in adult band-tailed pigeon survival estimates

    USGS Publications Warehouse

    Casazza, Michael L.; Coates, Peter S.; Overton, Cory T.; Howe, Kristy H.

    2015-01-01

    Implications: We present the first inter-seasonal analysis of survival probability of the Pacific coast race of band-tailed pigeons and illustrate important temporal patterns that may influence future species management including harvest strategies and disease monitoring.

  2. Effects of highly active antiretroviral therapy on the survival of HIV-infected adult patients in urban slums of Kenya.

    PubMed

    Muhula, Samuel Opondo; Peter, Memiah; Sibhatu, Biadgilign; Meshack, Ndirangu; Lennie, Kyomuhangi

    2015-01-01

    Recent improvements in access to Anti-Retroviral Therapy (ART) have radically reduced hospitalizations and deaths associated with HIV infection in both developed countries and sub-Saharan Africa. Not much is known about survival of patients on ART in slums. The objective of this study was to identify factors associated with mortality among adult patients on ART in resource poor, urban, sub-Saharan African setting. A prospective open cohort study was conducted with adult patients on ART at a clinic in Kibera slums, Nairobi, Kenya. The patients' enrollment to care was between March 2005 and November 2011. Descriptive statistics were computed and Kaplan-Meier (KM) methods used to estimate survival time while Cox's proportional hazards (CPH) model fitted to determine mortality predictors. A total of 2,011 adult patients were studied, 69% being female. Female gender (p=0.0016), zidovudine-based regimen patients (p<0.0001), CD4 count>351 patients (p<0.0001), WHO stage I patients (p<0.0001) and "Working" functional status patients recorded better survival probability on ART. In CPH analysis, the hazard of dying was higher in patients on Stavudine-based regimen(hazard ratio (HR)=.8; 95% CI, 1.5-2.2; p<0.0001),CD4 count<50 cells/µl (HR=1.6; 95% CI, 1.5-1.7;p<0.0001), WHO Stage IV at ART initiation (HR=1.3; 95% CI, 1.1-1.6; p=0.016) and bedridden patients (HR=2.7; 95% CI, 1.7-4.4;p<0.0001). There was increased mortality among the males, those with advanced Immunosuppression, late WHO stage and bedridden patients. The findings further justify the need to switch patients on Stavudine-based regimen as per the WHO recommendations. PMID:26090021

  3. Teaching Community Survival Skills to Mentally Retarded Adults: A Review and Analysis.

    ERIC Educational Resources Information Center

    Martin, James E.; And Others

    1982-01-01

    The article reviews research on training mentally retarded adults in the following community survival skills: travel training, money management, meal preparation, clothing and personal care, telephone skill, housekeeping, self-medication, leisure skills, social skills, and conversation. Results are said to indicate the value of behavioral…

  4. SURVIVAL AND ADULT EMERGENCE OF AQUATIC INSECTS IN AIR-SUPERSATURATED WATER

    EPA Science Inventory

    Mayflies Timpanoga hecuba, caddisflies Dicosmoecus gilvipes, mosquitoes Culex peus and midges Cricotopus sp. were tested in the laboratory to determine the effects of air-supersaturated water on survival and adult emergence. The acute 96-hour LC50 value (lethal concentration whic...

  5. Booster Sessions Enhance the Long-Term Effectiveness of Spaced Retrieval in Older Adults with Probable Alzheimer's Disease

    ERIC Educational Resources Information Center

    Cherry, Katie E.; Hawley, Karri S.; Jackson, Erin M.; Boudreaux, Emily O.

    2009-01-01

    Six older adults with probable Alzheimer's disease (AD) were trained to recall a name-face association using the spaced retrieval technique. In this study, we retested these persons in a 6-month follow-up program. For half of the participants, three booster sessions were administered at 6, 12, and 18 weeks after original training to promote…

  6. Spaced Retrieval Enhances Memory for a Name-Face-Occupation Association in Older Adults with Probable Alzheimer's Disease

    ERIC Educational Resources Information Center

    Cherry, Katie E.; Walvoord, Ashley A. G.; Hawley, Karri S.

    2010-01-01

    The authors trained 4 older adults with probable Alzheimer's disease to recall a name-face-occupation association using the spaced retrieval technique. Six training sessions were administered over a 2-week period. On each trial, participants selected a target photograph and stated the target name and occupation at increasingly longer retention…

  7. Survival of glucose phosphate isomerase null somatic cells and germ cells in adult mouse chimaeras.

    PubMed

    Keighren, Margaret A; Flockhart, Jean H; West, John D

    2016-01-01

    The mouse Gpi1 gene encodes the glycolytic enzyme glucose phosphate isomerase. Homozygous Gpi1(-/-) null mouse embryos die but a previous study showed that some homozygous Gpi1(-/-) null cells survived when combined with wild-type cells in fetal chimaeras. One adult female Gpi1(-/-)↔Gpi1(c/c) chimaera with functional Gpi1(-/-) null oocytes was also identified in a preliminary study. The aims were to characterise the survival of Gpi1(-/-) null cells in adult Gpi1(-/-)↔Gpi1(c/c) chimaeras and determine if Gpi1(-/-) null germ cells are functional. Analysis of adult Gpi1(-/-)↔Gpi1(c/c) chimaeras with pigment and a reiterated transgenic lineage marker showed that low numbers of homozygous Gpi1(-/-) null cells could survive in many tissues of adult chimaeras, including oocytes. Breeding experiments confirmed that Gpi1(-/-) null oocytes in one female Gpi1(-/-)↔Gpi1(c/c) chimaera were functional and provided preliminary evidence that one male putative Gpi1(-/-)↔Gpi1(c/c) chimaera produced functional spermatozoa from homozygous Gpi1(-/-) null germ cells. Although the male chimaera was almost certainly Gpi1(-/-)↔Gpi1(c/c), this part of the study is considered preliminary because only blood was typed for GPI. Gpi1(-/-) null germ cells should survive in a chimaeric testis if they are supported by wild-type Sertoli cells. It is also feasible that spermatozoa could bypass a block at GPI, but not blocks at some later steps in glycolysis, by using fructose, rather than glucose, as the substrate for glycolysis. Although chimaera analysis proved inefficient for studying the fate of Gpi1(-/-) null germ cells, it successfully identified functional Gpi1(-/-) null oocytes and revealed that some Gpi1(-/-) null cells could survive in many adult tissues. PMID:27103217

  8. Intentional genetic introgression influences survival of adults and subadults in a small, inbred felid population.

    PubMed

    Benson, John F; Hostetler, Jeffrey A; Onorato, David P; Johnson, Warren E; Roelke, Melody E; O'Brien, Stephen J; Jansen, Deborah; Oli, Madan K

    2011-09-01

    1. Inbreeding and low genetic diversity can cause reductions in individual fitness and increase extinction risk in animal populations. Intentional introgression, achieved by releasing genetically diverse individuals into inbred populations, has been used as a conservation tool to improve demographic performance in endangered populations. 2. By the 1980s, Florida panthers (Puma concolor coryi) had been reduced to a small, inbred population that appeared to be on the brink of extinction. In 1995, female pumas from Texas (P. c. stanleyana) were released in occupied panther range as part of an intentional introgression programme to restore genetic variability and improve demographic performance of panthers. 3. We used 25 years (1981-2006) of continuous radiotelemetry and genetic data to estimate and model subadult and adult panther survival and cause-specific mortality to provide rigorous sex and age class-specific survival estimates and evaluate the effect of the introgression programme on these parameters. 4. Genetic ancestry influenced annual survival of subadults and adults after introgression, as F(1) generation admixed panthers ( = 0·98) survived better than pre-introgression type panthers ( = 0·77) and other admixed individuals ( = 0·82). Furthermore, heterozygosity was higher for admixed panthers relative to pre-introgression type panthers and positively influenced survival. 5. Our results are consistent with hybrid vigour; however, extrinsic factors such as low density of males in some areas of panther range may also have contributed to higher survival of F(1) panthers. Regardless, improved survival of F(1) subadults and adults likely contributed to the numerical increase in panthers following introgression, and our results indicate that intentional admixture, achieved here by releasing individuals from another population, appears to have been successful in improving demographic performance in this highly endangered population. PMID:21338353

  9. Modelling adult Aedes aegypti and Aedes albopictus survival at different temperatures in laboratory and field settings

    PubMed Central

    2013-01-01

    Background The survival of adult female Aedes mosquitoes is a critical component of their ability to transmit pathogens such as dengue viruses. One of the principal determinants of Aedes survival is temperature, which has been associated with seasonal changes in Aedes populations and limits their geographical distribution. The effects of temperature and other sources of mortality have been studied in the field, often via mark-release-recapture experiments, and under controlled conditions in the laboratory. Survival results differ and reconciling predictions between the two settings has been hindered by variable measurements from different experimental protocols, lack of precision in measuring survival of free-ranging mosquitoes, and uncertainty about the role of age-dependent mortality in the field. Methods Here we apply generalised additive models to data from 351 published adult Ae. aegypti and Ae. albopictus survival experiments in the laboratory to create survival models for each species across their range of viable temperatures. These models are then adjusted to estimate survival at different temperatures in the field using data from 59 Ae. aegypti and Ae. albopictus field survivorship experiments. The uncertainty at each stage of the modelling process is propagated through to provide confidence intervals around our predictions. Results Our results indicate that adult Ae. albopictus has higher survival than Ae. aegypti in the laboratory and field, however, Ae. aegypti can tolerate a wider range of temperatures. A full breakdown of survival by age and temperature is given for both species. The differences between laboratory and field models also give insight into the relative contributions to mortality from temperature, other environmental factors, and senescence and over what ranges these factors can be important. Conclusions Our results support the importance of producing site-specific mosquito survival estimates. By including fluctuating temperature regimes

  10. Long Term Non-Invasive Ventilation in Children: Impact on Survival and Transition to Adult Care

    PubMed Central

    Chatwin, Michelle; Tan, Hui-Leng; Bush, Andrew; Rosenthal, Mark; Simonds, Anita Kay

    2015-01-01

    Background The number of children receiving domiciliary ventilatory support has grown over the last few decades driven largely by the introduction and widening applications of non-invasive ventilation. Ventilatory support may be used with the intention of increasing survival, or to facilitate discharge home and/or to palliate symptoms. However, the outcome of this intervention and the number of children transitioning to adult care as a consequence of longer survival is not yet clear. Methods In this retrospective cohort study, we analysed the outcome in children (<17 years) started on home NIV at Royal Brompton Hospital over an 18 year period 1993-2011. The aim was to establish for different diagnostic groups: survival rate, likelihood of early death depending on diagnosis or discontinuation of ventilation, and the proportion transitioning to adult care. Results 496 children were commenced on home non invasive ventilation; follow-up data were available in 449 (91%). Fifty six per cent (n=254) had neuromuscular disease. Ventilation was started at a median age (IQR) 10 (3-15) years. Thirteen percent (n=59) were less than 1 year old. Forty percent (n=181) have transitioned to adult care. Twenty four percent (n=109) of patients have died, and nine percent (n=42) were able to discontinue ventilatory support. Conclusion Long term ventilation is associated with an increase in survival in a range of conditions leading to ventilatory failure in children, resulting in increasing numbers surviving to adulthood. This has significant implications for planning transition and adult care facilities. PMID:25933065

  11. Novel estimates of Aedes aegypti (Diptera: Culicidae) population size and adult survival based on Wolbachia releases.

    PubMed

    Ritchie, Scott A; Montgomery, Brian L; Hoffmann, Ary A

    2013-05-01

    The size of Aedes aegypti (L.) mosquito populations and adult survival rates have proven difficult to estimate because of a lack of consistent quantitative measures to equate sampling methods, such as adult trapping, to actual population size. However, such estimates are critical for devising control methods and for modeling the transmission of dengue and other infectious agents carried by this species. Here we take advantage of recent releases of Wolbachia-infected Ae. aegypti coupled with the results of ongoing monitoring to estimate the size of adult Ae. aegypti populations around Cairns in far north Queensland, Australia. Based on the association between released adults infected with Wolbachia and data from Biogents Sentinel traps, we show that data from two locations are consistent with population estimates of approximately 5-10 females per house and daily survival rates of 0.7-0.9 for the released Wolbachia-infected females. Moreover, we estimate that networks of Biogents Sentinel traps at a density of one per 15 houses capture around 5-10% of the adult population per week, and provide a rapid estimate of the absolute population size of Ae. aegypti. These data are discussed with respect to release rates and monitoring in future Wolbachia releases and also the levels of suppression required to reduce dengue transmission. PMID:23802459

  12. Treatment and survival of supratentorial and posterior fossa ependymomas in adults.

    PubMed

    Nuño, Miriam; Yu, Jeffrey J; Varshneya, Kunal; Alexander, Julia; Mukherjee, Debraj; Black, Keith L; Patil, Chirag G

    2016-06-01

    Ependymoma is a rare primary brain or spinal cord tumor that arises from the ependyma, a tissue of the central nervous system. This study analyzed a large cohort of adult supratentorial and posterior fossa ependymoma tumors in order to elucidate factors associated with overall survival. We utilized the USA National Cancer Database to study adult World Health Organization grade II/III supratentorial and posterior fossa ependymoma patients treated between 1998 and 2011. Overall survival was estimated by the Kaplan-Meier method and factors associated with survival were determined using a multivariate Cox proportional hazards model. Among 1318 patients, 1055 (80.0%) had grade II and 263 (20.0%) anaplastic tumors located in the posterior fossa (64.3%) and supratentorial region (35.7%). Overall average age was 44.3years, 48.0% of patients were female, 86.5% were Caucasian, and 36.8% underwent near/gross total surgical resection. Radiotherapy was given to 662 patients (50.8%) and 75 (5.9%) received chemotherapy. Older age at diagnosis (hazard ratio [HR] 1.51, p<0.0001), high tumor grade (HR 1.82, p=0.005), and large tumor size (HR 1.66, p=0.008) were associated with poor survival. Females compared to males (HR 0.67, p=0.03) and patients with posterior fossa tumors versus supratentorial (HR 0.64, p=0.04) had a survival advantage. Our study showed that older patients, with supratentorial tumors, and high histological grade had an increased risk of mortality. A survival benefit was captured in females and patients with posterior fossa tumors. Adjuvant radiotherapy and chemotherapy did not confer a survival benefit among all patients, even after stratification by tumor grade or anatomical location. PMID:26810473

  13. Factors associated with survival in a contemporary adult sickle cell disease cohort.

    PubMed

    Elmariah, Hany; Garrett, Melanie E; De Castro, Laura M; Jonassaint, Jude C; Ataga, Kenneth I; Eckman, James R; Ashley-Koch, Allison E; Telen, Marilyn J

    2014-05-01

    In this study, the relationship of clinical differences among patients with sickle cell disease (SCD) was examined to understand the major contributors to early mortality in a contemporary cohort. Survival data were obtained for 542 adult subjects who were enrolled since 2002 at three university hospitals in the southeast United States. Subjects were followed up for a median of 9.3 years. At enrollment, clinical parameters were collected, including hemoglobin (Hb) genotype, baseline laboratory values, comorbidities, and medication usage. Levels of soluble adhesion molecules were measured for a subset of 87 subjects. The relationship of clinical characteristics to survival was determined using regression analysis. Median age at enrollment was 32 years. Median survival was 61 years for all subjects. Median survival for Hb SS and Sβ(0) was 58 years and for Hb SC and Sβ(+) was 66 years. Elevated white blood count, lower estimated glomerular filtration rate, proteinuria, frequency of pain crises, pulmonary hypertension, cerebrovascular events, seizures, stroke, sVCAM-1, and short-acting narcotics use were significantly associated with decreased survival. Forty-two percent of subjects were on hydroxyurea therapy, which was not associated with survival. SCD continues to reduce life expectancy for affected individuals, particularly those with Hb Sβ(0) and SS. Not only were comorbidities individually associated with decreased survival but also an additive effect was observed, thus, those with a greater number of negative endpoints had worse survival (P < 0.0001). The association of higher sVCAM-1 levels with decreased survival suggests that targeted therapies to reduce endothelial damage and inflammation may also be beneficial. PMID:24478166

  14. Survival of glucose phosphate isomerase null somatic cells and germ cells in adult mouse chimaeras

    PubMed Central

    Keighren, Margaret A.; Flockhart, Jean H.

    2016-01-01

    ABSTRACT The mouse Gpi1 gene encodes the glycolytic enzyme glucose phosphate isomerase. Homozygous Gpi1−/− null mouse embryos die but a previous study showed that some homozygous Gpi1−/− null cells survived when combined with wild-type cells in fetal chimaeras. One adult female Gpi1−/−↔Gpi1c/c chimaera with functional Gpi1−/− null oocytes was also identified in a preliminary study. The aims were to characterise the survival of Gpi1−/− null cells in adult Gpi1−/−↔Gpi1c/c chimaeras and determine if Gpi1−/− null germ cells are functional. Analysis of adult Gpi1−/−↔Gpi1c/c chimaeras with pigment and a reiterated transgenic lineage marker showed that low numbers of homozygous Gpi1−/− null cells could survive in many tissues of adult chimaeras, including oocytes. Breeding experiments confirmed that Gpi1−/− null oocytes in one female Gpi1−/−↔Gpi1c/c chimaera were functional and provided preliminary evidence that one male putative Gpi1−/−↔Gpi1c/c chimaera produced functional spermatozoa from homozygous Gpi1−/− null germ cells. Although the male chimaera was almost certainly Gpi1−/−↔Gpi1c/c, this part of the study is considered preliminary because only blood was typed for GPI. Gpi1−/− null germ cells should survive in a chimaeric testis if they are supported by wild-type Sertoli cells. It is also feasible that spermatozoa could bypass a block at GPI, but not blocks at some later steps in glycolysis, by using fructose, rather than glucose, as the substrate for glycolysis. Although chimaera analysis proved inefficient for studying the fate of Gpi1−/− null germ cells, it successfully identified functional Gpi1−/− null oocytes and revealed that some Gpi1−/− null cells could survive in many adult tissues. PMID:27103217

  15. The Mineralocorticoid Agonist Fludrocortisone Promotes Survival and Proliferation of Adult Hippocampal Progenitors

    PubMed Central

    Gesmundo, Iacopo; Villanova, Tania; Gargantini, Eleonora; Arvat, Emanuela; Ghigo, Ezio; Granata, Riccarda

    2016-01-01

    Glucocorticoid receptor (GR) activation has been shown to reduce adult hippocampal progenitor cell proliferation and neurogenesis. By contrast, mineralocorticoid receptor (MR) signaling is associated with neuronal survival in the dentate gyrus of the hippocampus, and impairment of hippocampal MR has been linked to pathological conditions, such as depression or neurodegenerative disorders. Here, we aimed to further clarify the protective role of MR in adult hippocampal neurons by studying the survival and proliferative effects of the highly potent MR agonist fludrocortisone (Fludro) in adult rat hippocampal progenitor cells (AHPs), along with the associated signaling mechanisms. Fludro, which upregulated MR but not GR expression, increased survival and proliferation and prevented apoptosis in AHPs cultured in growth factor-deprived medium. These effects were blunted by the MR antagonist spironolactone and by high doses of the GR agonist dexamethasone. Moreover, they involved signaling through cAMP/protein kinase A (PKA)/cAMP response element-binding protein, phosphoinositide 3-kinase (PI3K)/Akt and its downstream targets glycogen synthase kinase-3β (GSK-3β) and mammalian target of rapamycin. Furthermore, Fludro attenuated the detrimental effects of amyloid-β peptide 1–42 (Aβ1–42) on cell survival, proliferation, and apoptosis in AHPs, and increased the phosphorylation of both PI3K/Akt and GSK-3β, which was reduced by Aβ1–42. Finally, Fludro blocked Aβ1–42-induced hyperphosphorylation of Tau protein, which is a main feature of Alzheimer’s disease. Overall, these results are the first to show the protective and proliferative role of Fludro in AHPs, suggesting the potential therapeutic importance of targeting MR for increasing hippocampal neurogenesis and for treating neurodegenerative diseases. PMID:27379018

  16. Adult tree swallow (Tachycineta bicolor) survival on the polychlorinated biphenyl-contaminated Housatonic River, Massachusetts, USA

    USGS Publications Warehouse

    Custer, Christine M.; Custer, T.W.; Hines, J.E.; Nichols, J.D.; Dummer, P.M.

    2007-01-01

    Tree swallows (Tachycineta bicolor) were captured and banded at six sites that differed in polychlorinated biphenyl (PCB) contamination levels in the Housatonic River watershed, western Massachusetts, USA, from 2000 through 2004 to test the prediction that apparent survival rates of females in more contaminated areas were lower than those from less contaminated areas. We also tested whether plumage coloration affected over-winter survival and whether concentrations of PCBs in eggs differed between birds that did and that did not return the following year. Apparent survival rates were calculated using mark?recapture methods and compared using Akaike's Information Criterion. Model-adjusted survival rates ranged from 0.365 to 0.467 for PCB-contaminated females and between 0.404 and 0.476 for reference females. Models with either survival or capture probability modeled as functions of treatment (degree of PCB contamination), year, and age received some support. The model-averaged parameter estimate reflecting a treatment effect for high-PCB birds was negative ( = -0.046, SE() = 0.0939). Fifty-four percent of the total model weights involved models in which survival was a function of PCB treatment. Eggs were collected for contaminant analyses from a random sample of females that did and that did not return the following year. Concentrations of total PCBs were the same or higher in the eggs of females that returned compared to the eggs of those that did not return at both the highly and the moderately contaminated PCB sites. This may have resulted from higher-quality females with higher lipid reserves being more likely than lower-quality females to return the following year. Percentage lipid was positively correlated with total PCBs in eggs. Survival rates were similar among swallows with brown versus blue plumage.

  17. Adult tree swallow (Tachycineta bicolor) survival on the polychlorinated biphenyl-contaminated Housatonic River, Massachusetts, USA.

    PubMed

    Custer, Christine M; Custer, Thomas W; Hines, James E; Nichols, James D; Dummer, Paul M

    2007-05-01

    Tree swallows (Tachycineta bicolor) were captured and banded at six sites that differed in polychlorinated biphenyl (PCB) contamination levels in the Housatonic River watershed, western Massachusetts, USA, from 2000 through 2004 to test the prediction that apparent survival rates of females in more contaminated areas were lower than those from less contaminated areas. We also tested whether plumage coloration affected over-winter survival and whether concentrations of PCBs in eggs differed between birds that did and that did not return the following year. Apparent survival rates were calculated using mark-recapture methods and compared using Akaike's Information Criterion. Model-adjusted survival rates ranged from 0.365 to 0.467 for PCB-contaminated females and between 0.404 and 0.476 for reference females. Models with either survival or capture probability modeled as functions of treatment (degree of PCB contamination), year, and age received some support. The model-averaged parameter estimate reflecting a treatment effect for high-PCB birds was negative (beta = -0.046, SE(beta) = 0.0939). Fifty-four percent of the total model weights involved models in which survival was a function of PCB treatment. Eggs were collected for contaminant analyses from a random sample of females that did and that did not return the following year. Concentrations of total PCBs were the same or higher in the eggs of females that returned compared to the eggs of those that did not return at both the highly and the moderately contaminated PCB sites. This may have resulted from higher-quality females with higher lipid reserves being more likely than lower-quality females to return the following year. Percentage lipid was positively correlated with total PCBs in eggs. Survival rates were similar among swallows with brown versus blue plumage. PMID:17521155

  18. Motor imagery is less efficient in adults with probable developmental coordination disorder: evidence from the hand rotation task.

    PubMed

    Hyde, Christian; Fuelscher, Ian; Buckthought, Karen; Enticott, Peter G; Gitay, Maria A; Williams, Jacqueline

    2014-11-01

    The present study aimed to provide preliminary insight into the integrity of motor imagery (MI) in adults with probable developmental coordination disorder (pDCD). Based on a strong body of evidence indicating that paediatric samples of DCD often experience difficulties engaging MI, we hypothesised that young adults with pDCD would demonstrate similar difficulties. The performance of 12 young adults (19-35 years) with pDCD was compared to 47 age-matched controls on a traditional mental hand rotation task. Mean inverse efficiency scores were generated for each participant by dividing each participant's mean RT by their proportion of correct responses at each of the stimuli presentation conditions. Preliminary analysis revealed that the performance profiles of individuals with pDCD and age-matched controls showed evidence of being constrained by the biomechanical and postural constraints of real movement, suggesting that both groups engaged in an embodied (MI) strategy to complete the task. Despite engaging in a MI strategy, however, young adults with pDCD were nonetheless significantly less efficient when doing so, shown by significant main effects for group on all group efficiency comparisons. Based on the assumption that MI provides insight into the internal 'neural' action representation that precedes action, we argue that the less efficient MI performance demonstrated by young adults with pDCD may indicate inefficiencies engaging or implementing internal action representations. Implications and directions for future research are discussed. PMID:25134075

  19. Exploring Heterozygosity-Survival Correlations in a Wild Songbird Population: Contrasting Effects between Juvenile and Adult Stages

    PubMed Central

    Canal, David; Serrano, David; Potti, Jaime

    2014-01-01

    The relationship between genetic diversity and fitness, a major issue in evolutionary and conservation biology, is expected to be stronger in traits affected by many loci and those directly influencing fitness. Here we explore the influence of heterozygosity measured at 15 neutral markers on individual survival, one of the most important parameters determining individual fitness. We followed individual survival up to recruitment and during subsequent adult life of 863 fledgling pied flycatchers born in two consecutive breeding seasons. Mark-recapture analyses showed that individual heterozygosity did not influence juvenile or adult survival. In contrast, the genetic relatedness of parents was negatively associated with the offspring’s survival during the adult life, but this effect was not apparent in the juvenile (from fledgling to recruitment) stage. Stochastic factors experienced during the first year of life in this long-distance migratory species may have swamped a relationship between heterozygosity and survival up to recruitment. PMID:25122217

  20. Effect of noise and detector sensitivity on a dynamical process: inverse power law and Mittag-Leffler interevent time survival probabilities.

    PubMed

    Pramukkul, Pensri; Svenkeson, Adam; Grigolini, Paolo

    2014-02-01

    We study the combined effects of noise and detector sensitivity on a dynamical process that generates intermittent events mimicking the behavior of complex systems. By varying the sensitivity level of the detector we move between two forms of complexity, from inverse power law to Mittag-Leffler interevent time survival probabilities. Here fluctuations fight against complexity, causing an exponential truncation to the survival probability. We show that fluctuations of relatively weak intensity have a strong effect on the generation of Mittag-Leffler complexity, providing a reason why stretched exponentials are frequently found in nature. Our results afford a more unified picture of complexity resting on the Mittag-Leffler function and encompassing the standard inverse power law definition. PMID:25353422

  1. Effect of noise and detector sensitivity on a dynamical process: Inverse power law and Mittag-Leffler interevent time survival probabilities

    NASA Astrophysics Data System (ADS)

    Pramukkul, Pensri; Svenkeson, Adam; Grigolini, Paolo

    2014-02-01

    We study the combined effects of noise and detector sensitivity on a dynamical process that generates intermittent events mimicking the behavior of complex systems. By varying the sensitivity level of the detector we move between two forms of complexity, from inverse power law to Mittag-Leffler interevent time survival probabilities. Here fluctuations fight against complexity, causing an exponential truncation to the survival probability. We show that fluctuations of relatively weak intensity have a strong effect on the generation of Mittag-Leffler complexity, providing a reason why stretched exponentials are frequently found in nature. Our results afford a more unified picture of complexity resting on the Mittag-Leffler function and encompassing the standard inverse power law definition.

  2. Impaired Survival of Neural Progenitor Cells in Dentate Gyrus of Adult Mice Lacking FMRP

    PubMed Central

    Lazarov, Orly; Demars, Michael P.; Zhao, Kai Da Tommy; Ali, Haroon M.; Grauzas, Vanessa; Kney, Adam; Larson, John

    2011-01-01

    Fragile X syndrome (FXS) is the most common form of inherited intellectual disability in humans. Individuals affected with the disorder exhibit a deficiency of the fragile X mental retardation protein (FMRP), due to transcriptional silencing of the Fmr1 gene. It is widely accepted that learning deficits in FXS result from impaired synaptic function and/or plasticity in the brain. Interestingly, recent evidence suggests that conditional knockout of Fmr1 in neural progenitor cells in mice impairs hippocampal neurogenesis, which in turn contributes to learning impairments. To examine the nature of the neurogenic impairments and determine whether they impact the morphology of the dentate gyrus, we assessed the extent of neural progenitor cell proliferation, survival, and differentiation in older adult Fmr1 knockout mice. Here we show that the number of fast- proliferating cells in the subgranule layer of the dentate gyrus, as well as the subsequent survival of these cells, are dramatically reduced in Fmr1 knockout mice. In addition, the number of mature neurons in the granule layer of the dentate gyrus of these mice is significantly smaller than in WT littermate controls, suggesting that impaired proliferation and survival of neural progenitor cells compromises the structure of the dentate gyrus. Impaired adult neurogenesis may underlie, at least in part, the learning deficits that characterize fragile X syndrome. PMID:22128095

  3. Burmese political dissidents in Thailand: trauma and survival among young adults in exile.

    PubMed Central

    Allden, K; Poole, C; Chantavanich, S; Ohmar, K; Aung, N N; Mollica, R F

    1996-01-01

    OBJECTIVES: This study assessed the self-reported mental health, physical health, and social functioning of young adult political exiles and relates their psychiatric symptoms to their trauma and survival strategies. METHODS: A 1992/93 survey of Burmese who fled to Bangkok, Thailand, after participating in a 1988 uprising against Burma's government elicited information on employment, education, disability, trauma, survival strategies, and depressive and posttraumatic stress symptoms. RESULTS: The 104 participants reported a mean of 30 trauma events, including interrogation (89%), imprisonment (78%), threats of deportation (70%), and torture (38%). Many reported poor health and lack of social supports, but few reported substantial social disability. The prevalence of elevated symptom scores was 38% for depressive symptoms and 23% for criterion symptoms of posttraumatic stress disorder. Symptoms of avoidance and of increased arousal were the most strongly related to cumulative trauma. Two survival strategies, camaraderie and a Buddhist concept of self-confidence (weria), were associated with somewhat reduced levels of both classes of symptoms. CONCLUSIONS: Burmese political exiles in Thailand are young adults adversely affected by severe trauma. Their psychosocial well-being may deteriorate further without legal protections to reduce the continuing stress and violence. PMID:8916521

  4. Effect of pesticides on adult rove beetle Atheta coriaria (Coleoptera: Staphylinidae) survival in growing medium.

    PubMed

    Cloyd, Raymond A; Timmons, Nicholas R; Goebel, Jessica M; Kemp, Kenneth E

    2009-10-01

    The rove beetle Atheta coriaria (Kraatz) (Coleoptera: Staphylinidae) is a natural enemy (biological control agent) commercially available for control of certain greenhouse insect pests, including fungus gnats, shore flies, and thrips. This study assessed the compatibility of pesticides (insecticides and fungicides) used in greenhouses with A. coriaria adults. Treatments were applied to 473-ml deli squat containers half-filled with a growing medium. We evaluated the effects of the pesticides when releases of A. coriaria adults were performed both before and after application of the designated pesticide solutions. All three of the neonicotinoid-based insecticides (clothianidin, dinotefuran, and thiamethoxam) were directly harmful to A. coriaria adults with < or = 3.2 adults recovered (out of 20) among all three treatments across all experiments. In addition, the organophosphate insecticide chlorpyrifos at the low (0.25 fl oz/100 gal) and high (0.50 fl oz/100 gal) label rates; the plant-derived essential oil product (Indoor Pharm) containing soybean and rosemary oil; and the insecticide/miticide chlorfenpyr were directly harmful to A. coriaria adults with recovery rates -8.6 (out of 20) among all the treatments. The fungicides (azoxystrobin, fosetyl-aluminum, and mefenoxam) were not directly toxic to A. coriaria adults, with < or = 17.7 adults recovered (out of 20) across all experiments. The insecticides (Bacillus thuringiensis subsp. israelensis, flonicamid, Metarhizium anisopliae strain52, and spinosad) and insect growth regulator azadirachtin were also not directly toxic to A. coriaria adults. Furthermore, many of these same treatments did not inhibit the ability of adult A. coriaria to consume fungus gnat (Bradysia sp. nr. coprophila) larvae in a feeding behavior experiment. Although the neonicotinoid-based insecticides were directly harmful to adult A. coriaria, when adults were released 48, 72, or 96 h after application, survival increased dramatically over

  5. Stress, Social Support, and Outcomes in Two Probability Samples of Homeless Adults

    ERIC Educational Resources Information Center

    Toro, Paul A.; Tulloch, Elizabeth; Ouellette, Nicole

    2008-01-01

    This study investigated the main effects of social support measures and their stress-buffering effects in two samples of homeless adults (Ns =249 and 219) obtained in the same large county (surrounding Detroit) at different points in time over an 8-year period (1992-1994 and 2000-2002). The findings suggest that the construct of social support,…

  6. Trends in survival for teenagers and young adults with cancer in the UK 1992–2006

    PubMed Central

    O’Hara, C.; Moran, A.; Whelan, J.S.; Hough, R.E.; Stiller, C.A.; Stevens, M.C.G.; Stark, D.P.; Feltbower, R.G.; McCabe, M.G.

    2015-01-01

    Background Although relatively rare, cancer in teenagers and young adults (TYA) is the most common disease-related cause of death and makes a major contribution to years of life lost in this age group. There is a growing awareness of the distinctive needs of this age group and drive for greater understanding of how outcomes can be improved. We present here the latest TYA survival trends data for the United Kingdom (UK). Methods Using national cancer registry data, we calculated five-year relative survival for all 15–24 year olds diagnosed with cancer or a borderline/benign CNS tumour in the UK during the periods 1992–1996, 1997–2001 and 2002–2006. We analysed trends in survival for all cancers combined and for eighteen specified groups that together represent the majority of TYA cancers. We compared our data with published data for Europe, North America and Australia. Results Five-year survival for all cancers combined increased from 75.5% in 1992–1996 to 82.2% in 2002–2006 (P < 0.001). Statistically significant improvements were seen for all disease groups except osteosarcoma, rhabdomyosarcoma, non-gonadal and ovarian germ cell tumours and ovarian and thyroid carcinomas. During the earliest time period, females had significantly better survival than males for five of the twelve non-gender-specific disease groups. By the latest period, only melanomas and non-rhabdomyosarcoma soft tissue sarcomas had differential survival by gender. Survival in the UK for the most recent period was generally similar to other comparable countries. Conclusion Five-year survival has improved considerably in the UK for most cancer types. For some disease groups, there has been little progress, either because survival already approaches 100% (e.g. thyroid carcinomas) or, more worryingly for some cancers with poor outcomes, because they remain resistant to existing therapy (e.g. rhabdomyosarcoma). In addition, for a number of specific cancer types and for cancer as a whole

  7. Posterior brain white matter abnormalities in older adults with probable mild cognitive impairment

    PubMed Central

    Cooley, Sarah A.; Cabeen, Ryan P.; Laidlaw, David H.; Conturo, Thomas E.; Lane, Elizabeth M.; Heaps, Jodi M.; Bolzenius, Jacob D.; Baker, Laurie M.; Salminen, Lauren E.; Scott, Staci E.; Paul, Robert H.

    2014-01-01

    Objective Much of the mild cognitive impairment (MCI) neuroimaging literature has exclusively focused on regions associated with Alzheimer’s disease. Little research has examined white matter abnormalities of other brain regions, including those associated with visual processing, despite evidence that other brain abnormalities appear in these regions in early disease stages. Method Diffusion tensor imaging (DTI) was utilized to examine participants (n = 44) that completed baseline imaging as part of a longitudinal healthy aging study. Participants were divided into two groups based on scores from the Montreal Cognitive Assessment (MoCA), a brief screening tool for MCI. Participants who scored < 26 were defined as “probable MCI” while those who scored ≥ 26 were labled cognitively healthy. Two DTI indices were analyzed including fractional anisotropy (FA) and mean diffusivity (MD). DTI values for white matter in the lingual gyrus, cuneus, pericalcarine, fusiform gyrus and all four lobes were compared using MANOVA. Regression analyses examined the relationship between DTI indices and total MoCA score. Results Results revealed significantly lower FA in the probable MCI group in the cuneus, fusiform, pericalcarine and occipital lobe, and significantly higher MD in the temporal lobe. Fusiform FA and temporal lobe MD were significantly related to total MoCA score after accounting for age and education. Conclusions Results indicate that there are posterior white matter microstructural changes in individuals with probable MCI. These differences demonstrate that white matter abnormalities are evident among individuals with probable MCI in regions beyond those commonly associated with Alzheimer’s disease and anterior brain aging patterns. PMID:25523313

  8. The probability distribution of the amount of an individual`s genome surviving to the following generation

    SciTech Connect

    Bickeboeller, H.; Thompson, E.A.

    1996-06-01

    The results of this probability study concerning the heredity of the human genome state that it is very likely that an individual with at least 4 children passes on at least 90% of his genome. These results occur when an important assumption - the genomic continuum model - is made. 12 refs., 3 figs., 2 tabs.

  9. Long-Term Survival of Photoreceptors Transplanted into the Adult Murine Neural Retina Requires Immune Modulation

    PubMed Central

    West, Emma L.; Pearson, Rachael A.; Barker, Susie E.; Luhmann, Ulrich F. O.; Maclaren, Robert E.; Barber, Amanda C.; Duran, Yanai; Smith, Alexander J.; Sowden, Jane C.; Ali, Robin R.

    2012-01-01

    Stem cell therapy presents an opportunity to replace photoreceptors that are lost as a result of inherited and age-related degenerative disease. We have previously shown that murine postmitotic rod photoreceptor precursor cells, identified by expression of the rod-specific transcription factor Nrl, are able to migrate into and integrate within the adult murine neural retina. However, their long-term survival has yet to be determined. Here, we found that integrated Nrl.gfp+ve photoreceptors were present up to 12 months post-transplantation, albeit in significantly reduced numbers. Surviving cells had rod-like morphology, including inner/outer segments and spherule synapses. In a minority of eyes, we observed an early, marked reduction in integrated photoreceptors within 1 month post-transplantation, which correlated with increased numbers of amoeboid macrophages, indicating acute loss of transplanted cells due to an inflammatory response. In the majority of transplants, similar numbers of integrated cells were observed between 1 and 2 months post-transplantation. By 4 months, however, we observed a significant decrease in integrated cell survival. Macrophages and T cells were present around the transplantation site, indicating a chronic immune response. Immune suppression of recipients significantly increased transplanted photoreceptor survival, indicating that the loss observed in unsuppressed recipients resulted from T cell-mediated host immune responses. Thus, if immune responses are modulated, correctly integrated transplanted photoreceptors can survive for extended periods of time in hosts with partially mismatched H-2 haplotypes. These findings suggest that autologous donor cells are optimal for therapeutic approaches to repair the neural retina, though with immune suppression nonautologous donors may be effective. PMID:20857496

  10. Knockout of Atg5 delays the maturation and reduces the survival of adult-generated neurons in the hippocampus

    PubMed Central

    Xi, Y; Dhaliwal, J S; Ceizar, M; Vaculik, M; Kumar, K L; Lagace, D C

    2016-01-01

    Autophagy is an evolutionarily conserved lysosomal degradation pathway that plays important roles in cell maintenance, expansion and differentiation. Removal of genes essential for autophagy from embryonic neural stem and precursor cells reduces the survival and inhibits neuronal differentiation of adult-generated neurons. No study has modified autophagy within the adult precursor cells, leaving the cell-autonomous role of autophagy in adult neurogenesis unknown. Here we demonstrate that autophagic flux exists in the adult dividing progenitor cells and their progeny in the dentate gyrus. To investigate the role of autophagy in adult hippocampal neurogenesis, we genetically deleted Autophagy-related gene 5 (Atg5) that reduced autophagic flux and the survival of the progeny of dividing progenitor cells. This significant reduction in survival of adult-generated neurons is accompanied by a delay in neuronal maturation, including a transient reduction in spine density in the absence of a change in differentiation. The delay in cell maturation and loss of progeny of the Atg5-null cells was not present in mice that lacked the essential pro-apoptotic protein Bax (Bcl-2-associated X protein), suggesting that Atg5-deficient cells die through a Bax-dependent mechanism. In addition, there was a loss of Atg5-null cells following exposure to running, suggesting that Atg5 is required for running-induced increases in neurogenesis. These findings highlight the cell-autonomous requirement of Atg5 in the survival of adult-generated neurons. PMID:26938300

  11. Multicenter study on caries risk assessment in adults using survival Classification and Regression Trees

    PubMed Central

    Arino, Masumi; Ito, Ataru; Fujiki, Shozo; Sugiyama, Seiichi; Hayashi, Mikako

    2016-01-01

    Dental caries is an important public health problem worldwide. This study aims to prove how preventive therapies reduce the onset of caries in adult patients, and to identify patients with high or low risk of caries by using Classification and Regression Trees based survival analysis (survival CART). A clinical data set of 732 patients aged 20 to 64 years in nine Japanese general practices was analyzed with the following parameters: age, DMFT, number of mutans streptococci (SM) and Lactobacilli (LB), secretion rate and buffer capacity of saliva, and compliance with a preventive program. Results showed the incidence of primary carious lesion was affected by SM, LB and compliance with a preventive program; secondary carious lesion was affected by DMFT, SM and LB. Survival CART identified high-risk patients for primary carious lesion according to their poor compliance with a preventive program and SM (≥106 CFU/ml) with a hazard ratio of 3.66 (p = 0.0002). In the case of secondary caries, patients with LB (≥105 CFU/ml) and DMFT (>15) were identified as high risk with a hazard ratio of 3.50 (p < 0.0001). We conclude that preventive programs can be effective in limiting the incidence of primary carious lesion. PMID:27381750

  12. Multicenter study on caries risk assessment in adults using survival Classification and Regression Trees.

    PubMed

    Arino, Masumi; Ito, Ataru; Fujiki, Shozo; Sugiyama, Seiichi; Hayashi, Mikako

    2016-01-01

    Dental caries is an important public health problem worldwide. This study aims to prove how preventive therapies reduce the onset of caries in adult patients, and to identify patients with high or low risk of caries by using Classification and Regression Trees based survival analysis (survival CART). A clinical data set of 732 patients aged 20 to 64 years in nine Japanese general practices was analyzed with the following parameters: age, DMFT, number of mutans streptococci (SM) and Lactobacilli (LB), secretion rate and buffer capacity of saliva, and compliance with a preventive program. Results showed the incidence of primary carious lesion was affected by SM, LB and compliance with a preventive program; secondary carious lesion was affected by DMFT, SM and LB. Survival CART identified high-risk patients for primary carious lesion according to their poor compliance with a preventive program and SM (≥10(6) CFU/ml) with a hazard ratio of 3.66 (p = 0.0002). In the case of secondary caries, patients with LB (≥10(5) CFU/ml) and DMFT (>15) were identified as high risk with a hazard ratio of 3.50 (p < 0.0001). We conclude that preventive programs can be effective in limiting the incidence of primary carious lesion. PMID:27381750

  13. Racial Disparities and Colorectal Cancer Survival in Older Adults With and Without Diabetes Mellitus

    PubMed Central

    Waheed, Salman; Azad, Nilofer; Waheed, Sehrish; Yeh, Hsin-Chieh

    2015-01-01

    Objective To investigate whether pre-existing diabetes modifies racial disparities in colorectal cancer (CRC) survival. Research Design and Methods We analyzed prospective data from 16,977 patients (age≥67 years) with CRC from the Surveillance Epidemiology and End Results (SEER)-Medicare database. SEER registries included data on demographics, tumor characteristics, and treatment. Medicare claims were used to define pre-existing diabetes and comorbid conditions. Mortality was confirmed in both sources. Results At baseline, 1,332 (8%) were African-Americans and 26% had diabetes (39% in blacks; 25% in whites). From 2000 to 2005, more than half of the participants died (N=8,782, 52%). This included 820 (62%) deaths (23.8 per 100 per-years) among blacks, and 7,962 (51%) deaths (16.6 per 100 person-years) among whites. Among older adults with diabetes, blacks had significantly higher risk of all-cause and CRC mortality after adjustments for demographic characteristics, [hazard ratio (HR), 95% confidence interval (CI): 1.21 (1.08–1.37) and 1.21 (1.03–1.42)], respectively, but these associations attenuated to null after additional adjustments for cancer stage and grade. Among adults without diabetes, the risk of all-cause mortality [HR (95% CI): 1.14 (1.04–1.25)] and CRC mortality [HR (95% CI): 1.21 (1.08–1.36)] remained higher in blacks than whites in fully-adjusted models that included demographic variables, cancer stage, grade, treatments, and co-morbidities. Conclusions Among older adults with CRC, diabetes is an effect modifier on the relationship between race and mortality. Racial disparities in survival were explained by demographics, cancer stage and grade in patients with diabetes. PMID:24909501

  14. Doublecortin (DCX) is not Essential for Survival and Differentiation of Newborn Neurons in the Adult Mouse Dentate Gyrus

    PubMed Central

    Dhaliwal, Jagroop; Xi, Yanwei; Bruel-Jungerman, Elodie; Germain, Johanne; Francis, Fiona; Lagace, Diane C.

    2016-01-01

    In the adult brain, expression of the microtubule-associated protein Doublecortin (DCX) is associated with neural progenitor cells (NPCs) that give rise to new neurons in the dentate gyrus. Many studies quantify the number of DCX-expressing cells as a proxy for the level of adult neurogenesis, yet no study has determined the effect of removing DCX from adult hippocampal NPCs. Here, we use a retroviral and inducible mouse transgenic approach to either knockdown or knockout DCX from adult NPCs in the dentate gyrus and examine how this affects cell survival and neuronal maturation. Our results demonstrate that shRNA-mediated knockdown of DCX or Cre-mediated recombination in floxed DCX mice does not alter hippocampal neurogenesis and does not change the neuronal fate of the NPCs. Together these findings show that the survival and maturation of adult-generated hippocampal neurons does not require DCX. PMID:26793044

  15. Estimating the effect of hunting on annual survival rates of adult mallards

    USGS Publications Warehouse

    Burnham, Kenneth P.; White, Gary C.; Anderson, David R.

    1984-01-01

    Management programs for waterfowl populations include rationale for, and establishment of, hunting regulations. These programs rest partially on the results of scientific studies on the effect of harvest rates on annual survival rates. The evidence of this relationship has changed markedly since the mid-1970's, and it is not widely believed that a largely compensatory relationship exists between hunting mortality and other forms of mortality for the mallard (Anas platyrhynchos). This paper employs a general probabilistic model formulated to include a parameter (b) representing a continuum between complete compensation (b=0) and total additivity (b=1). Maximum likelihood estimates of this parameter were computer for 47 data sets of adult mallards banded throughout North American before hunting commenced. We found additional evidence of a highly compensatory mortality process for adult male mallards, while the evidence for adults female mallards remains inconclusive. Effective harvest, land acquisition, and land management programs depend upon additional information on the chronology and mechanisms underlying a compensatory mortality process.

  16. Early-life disease exposure and associations with adult survival, cause of death, and reproductive success in preindustrial humans.

    PubMed

    Hayward, Adam D; Rigby, Francesca L; Lummaa, Virpi

    2016-08-01

    A leading hypothesis proposes that increased human life span since 1850 has resulted from decreased exposure to childhood infections, which has reduced chronic inflammation and later-life mortality rates, particularly from cardiovascular disease, stroke, and cancer. Early-life cohort mortality rate often predicts later-life survival in humans, but such associations could arise from factors other than disease exposure. Additionally, the impact of early-life disease exposure on reproduction remains unknown, and thus previous work ignores a major component of fitness through which selection acts upon life-history strategy. We collected data from seven 18th- and 19th-century Finnish populations experiencing naturally varying mortality and fertility levels. We quantified early-life disease exposure as the detrended child mortality rate from infectious diseases during an individual's first 5 y, controlling for important social factors. We found no support for an association between early-life disease exposure and all-cause mortality risk after age 15 or 50. We also found no link between early-life disease exposure and probability of death specifically from cardiovascular disease, stroke, or cancer. Independent of survival, there was no evidence to support associations between early-life disease exposure and any of several aspects of reproductive performance, including lifetime reproductive success and age at first birth, in either males or females. Our results do not support the prevailing assertion that exposure to infectious diseases in early life has long-lasting associations with later-life all-cause mortality risk or mortality putatively linked to chronic inflammation. Variation in adulthood conditions could therefore be the most likely source of recent increases in adult life span. PMID:27457937

  17. Cancer of Unknown Primary in Adolescents and Young Adults: Clinicopathological Features, Prognostic Factors and Survival Outcomes

    PubMed Central

    Raghav, Kanwal; Mhadgut, Hemendra; McQuade, Jennifer L.; Lei, Xiudong; Ross, Alicia; Matamoros, Aurelio; Wang, Huamin; Overman, Michael J.; Varadhachary, Gauri R.

    2016-01-01

    Background Cancer in adolescents and young adults (AYAs) (15–39 years) is increasingly recognized as a distinct clinical and biological entity. Cancer of unknown primary (CUP), a disease traditionally presenting in older adults with a median age of 65 years, poses several challenges when diagnosed in AYA patients. This study describes clinicopathological features, outcomes and challenges in caring for AYA-CUP patients. Methods A retrospective review of 47 AYAs diagnosed with CUP at MD Anderson Cancer Center (6/2006–6/2013) was performed. Patients with favorable CUP subsets treated as per site-specific recommendations were excluded. Demographics, imaging, pathology and treatment data was collected using a prospectively maintained CUP database. Kaplan-Meier product limit method and log-rank test were used to estimate and compare overall survival. The cox-proportional model was used for multivariate analyses. Results Median age was 35 years (range 19–39). All patients underwent comprehensive workup. Adenocarcinoma was the predominant histology (70%). A median of 9 immunostains (range 2–29) were performed. The most common putative primary was biliary tract based on clinicopathological parameters as well as gene profiling. Patients presented with a median of 2 metastatic sites [lymph node (60%), lung (47%), liver (38%) and bone (34%)]. Most commonly used systemic chemotherapies included gemcitabine, fluorouracil, taxanes and platinum agents. Median overall survival for the entire cohort was 10.0 (95% confidence interval (CI): 6.7–15.4) months. On multivariate analyses, elevated lactate dehydrogenase (Hazard ratio (HR) 3.66; 95%CI 1.52–8.82; P = 0.004), ≥3 metastatic sites (HR 5.34; 95%CI 1.19–23.9; P = 0.029), and tissue of origin not tested (HR 3.4; 95%CI 1.44–8.06; P = 0.005) were associated with poor overall survival. Culine’s CUP prognostic model (lactate dehydrogenase, performance status, liver metastases) was validated in this cohort (median

  18. Effects of distraction and pictorial illustration on memory for countries in older adults with probable Alzheimer's disease.

    PubMed

    Boudreaux, Emily O; Cherry, Katie E; Elliott, Emily M; Hicks, Jason L

    2011-05-01

    Eight participants with probable Alzheimer's disease (AD) were trained to recall names of countries using the spaced-retrieval memory intervention. Six training sessions were administered on alternate days over a 2-week period. Half of the participants studied a target country alone and the other half studied a target country along with eight distractor countries. Training stimuli appeared in text-only format in half of the sessions and text with a color photograph of the country in the other sessions. On each trial, participants selected the target at increasingly longer retention intervals, contingent upon successful recall. Results indicated that the mean proportion of correct trials and longest duration achieved increased across training sessions, confirming the success of the spaced-retrieval intervention. Pictorial illustrations enhanced explicit memory for target country names. Implications of these data for current views on memory remediation in cognitively impaired older adults are discussed. PMID:21534030

  19. Adult neural precursor cells form connexin-dependent networks that improve their survival.

    PubMed

    Ravella, Ajaya; Ringstedt, Thomas; Brion, Jean-Pierre; Pandolfo, Massimo; Herlenius, Eric

    2015-10-21

    Establishment of cellular networks and calcium homeostasis are essential for embryonic stem cell proliferation and differentiation. We also hypothesized that adult neural progenitor cells form functional cellular networks relevant for their development. We isolated neuronal progenitor cells from the subventricular zone of 5-week-old mice to investigate the role of gap junctions, calcium homeostasis, and cellular networks in cell differentiation and survival. Western blotting and reverse transcription-PCR showed that the cells expressed the gap junction components connexin 26, 36, 43, and 45, and that expression of connexin 43 increased in early (8 days) differentiated cells. Transmission electron microscopy and immunocytochemistry also indicated that gap junctions were present. Scrape-loading experiments showed dye transfer between cells that could be prevented by gapjunction blockers; thus, functional intercellular gap junctions had been established. However, dye transfer was four times stronger in differentiated cultures, correlating with the increased connexin 43 expression. During time-lapse calcium imaging, both differentiated and undifferentiated cultures showed spontaneous calcium activity that was reduced by gap junction blockers. Cross-correlation analysis of the calcium recordings showed that the cells were interconnected through gap junctions and that the early-differentiated cells were organized in small-world networks. Gap junction blockers did not affect proliferation and differentiation, but resulted in twice as many apoptotic cells. mRNAi knockdown of connexin 43 also doubled the number of apoptotic cells. We conclude that adult neural progenitor cells form networks in vitro that are strengthened during early differentiation by increased expression of connexin 43. The networks are functional and improve cell survival. PMID:26351758

  20. Absence of a Socioeconomic Gradient in Older Adults' Survival with Multiple Chronic Conditions

    PubMed Central

    Lane, Natasha E.; Maxwell, Colleen J.; Gruneir, Andrea; Bronskill, Susan E.; Wodchis, Walter P.

    2015-01-01

    Background Individuals of low socioeconomic status experience a disproportionate burden of chronic conditions; however it is unclear whether chronic condition burden affects survival differently across socioeconomic strata. Methods This retrospective cohort study used health administrative data from all residents of Ontario, Canada aged 65 to 105 with at least one of 16 chronic conditions on April 1, 2009 (n = 1,518,939). Chronic condition burden and unadjusted mortality were compared across neighborhood income quintiles. Multivariable Cox proportional hazards models were used to examine the effect of number of chronic conditions on two-year survival across income quintiles. Findings Prevalence of five or more chronic conditions was significantly higher among older adults in the poorest neighborhoods (18.2%) than the wealthiest (14.3%) (Standardized difference > 0·1). There was also a socioeconomic gradient in unadjusted mortality over two years: 10.1% of people in the poorest neighborhoods died compared with 7.6% of people in the wealthiest neighborhoods. In adjusted analyses, having more chronic conditions was associated with a statistically significant increase in hazard of death over two years, however the magnitude of this effect was comparable across income quintiles. Individuals in the poorest neighborhoods with four chronic conditions had 2.07 times higher hazard of death (95% CI: 1.97–2.19) than those with one chronic condition, but this was comparable to the hazard associated with four chronic conditions in the wealthiest neighborhoods (HR: 2.29, 95% CI: 2.16–2.43). Interpretation Among older adults with universal access to health care, the deleterious effect of increasing chronic condition burden on two-year hazard of death was consistent across neighborhood income quintiles once baseline differences in condition burden were accounted for. This may be partly attributable to equal access to, and utilization of, health care. Alternate explanations

  1. Hearing loss in adults surviving pneumococcal meningitis is associated with otitis and pneumococcal serotype.

    PubMed

    Heckenberg, S G B; Brouwer, M C; van der Ende, A; Hensen, E F; van de Beek, D

    2012-09-01

    We assessed the incidence of hearing loss and its relationship with clinical characteristics and pneumococcal serotypes in adults surviving pneumococcal meningitis. We analysed hearing loss in 531 adults surviving pneumococcal meningitis included in two prospective nationwide cohort studies performed from April 1998 through to October 2002 and March 2006 through to January 2009. Hearing loss was evaluated on admission and discharge for all patients. Severe hearing loss was assessed by pure tone average on audiology and corrected for age, or by the combination of hearing loss on discharge and a score on the Glasgow Outcome Scale below 5, which could not be explained by other neurological sequelae. A total of 531 episodes of pneumococcal meningitis with non-lethal outcome were included. Predisposing conditions for pneumococcal meningitis were present in the majority of patients (64%), most commonly otitis (36%). Hearing loss was present at discharge in 116 patients (22%) and was classified as mild in 53% and severe in 47%. Hearing loss was related to otitis (odds ratio [OR], 2.58; 95% confidence interval [CI], 1.66-4.02; p < 0.001) and inversely related to serotype 23 F infection (OR, 0.36; 95% CI, 0.13-0.98; p = 0.025), but not with parameters of disease severity or indicators of cerebrospinal fluid inflammation severity. Meningitis due to pneumococcal serotype 3 was associated with the highest rate of hearing loss. Hearing loss frequently complicates pneumococcal meningitis. Risk factors for hearing loss were infection with pneumococcal serotype 23 F and otitis, but not disease severity. Otitis and resulting perilympathic inflammation contribute to meningitis-associated hearing loss. PMID:21958295

  2. Association Between Helicopter vs Ground Emergency Medical Services and Survival for Adults With Major Trauma

    PubMed Central

    Galvagno, Samuel M.; Haut, Elliott R.; Zafar, S. Nabeel; Millin, Michael G.; Efron, David T.; Koenig, George J.; Baker, Susan P.; Bowman, Stephen M.; Pronovost, Peter J.; Haider, Adil H.

    2012-01-01

    Context Helicopter emergency medical services and their possible effect on outcomes for traumatically injured patients remain a subject of debate. Because helicopter services are a limited and expensive resource, a methodologically rigorous investigation of its effectiveness compared with ground emergency medical services is warranted. Objective To assess the association between the use of helicopter vs ground services and survival among adults with serious traumatic injuries. Design, Setting, and Participants Retrospective cohort study involving 223 475 patients older than 15 years, having an injury severity score higher than 15, and sustaining blunt or penetrating trauma that required transport to US level I or II trauma centers and whose data were recorded in the 2007–2009 versions of the American College of Surgeons National Trauma Data Bank. Interventions Transport by helicopter or ground emergency services to level I or level II trauma centers. Main Outcome Measures Survival to hospital discharge and discharge disposition. Results A total of 61 909 patients were transported by helicopter and 161 566 patients were transported by ground. Overall, 7813 patients (12.6%) transported by helicopter died compared with 17 775 patients (11%) transported by ground services. Before propensity score matching, patients transported by helicopter to level I and level II trauma centers had higher Injury Severity Scores. In the propensity score–matched multivariable regression model, for patients transported to level I trauma centers, helicopter transport was associated with an improved odds of survival compared with ground transport (odds ratio [OR], 1.16; 95% CI, 1.14–1.17; P<.001; absolute risk reduction [ARR], 1.5%). For patients transported to level II trauma centers, helicopter transport was associated with an improved odds of survival (OR, 1.15; 95% CI, 1.13–1.17; P < .001; ARR, 1.4%). A greater proportion (18.2%) of those transported to level I trauma centers

  3. Role for protein geranylgeranylation in adult T-cell leukemia cell survival

    SciTech Connect

    Nonaka, Mizuho; Uota, Shin; Saitoh, Yasunori; Takahashi, Mayumi; Sugimoto, Haruyo; Amet, Tohti; Arai, Ayako; Miura, Osamu; Yamamoto, Naoki; Yamaoka, Shoji

    2009-01-15

    Adult T-cell leukemia (ATL) is a fatal lymphoproliferative disease that develops in human T-cell leukemia virus type I (HTLV-I)-infected individuals. Despite the accumulating knowledge of the molecular biology of HTLV-I-infected cells, effective therapeutic strategies remain to be established. Recent reports showed that the hydroxyl-3-methylglutaryl (HMG)-CoA reductase inhibitor statins have anti-proliferative and apoptotic effects on certain tumor cells through inhibition of protein prenylation. Here, we report that statins hinder the survival of ATL cells and induce apoptotic cell death. Inhibition of protein geranylgeranylation is responsible for these effects, since simultaneous treatment with isoprenoid precursors, geranylgeranyl pyrophosphate or farnesyl pyrophosphate, but not a cholesterol precursor squalene, restored the viability of ATL cells. Simvastatin inhibited geranylgeranylation of small GTPases Rab5B and Rac1 in ATL cells, and a geranylgeranyl transferase inhibitor GGTI-298 reduced ATL cell viability more efficiently than a farnesyl transferase inhibitor FTI-277. These results not only unveil an important role for protein geranylgeranylation in ATL cell survival, but also implicate therapeutic potentials of statins in the treatment of ATL.

  4. Birth, survival and differentiation of neurons in an adult crustacean brain.

    PubMed

    Kim, Youngmi Faith; Sandeman, David C; Benton, Jeanne L; Beltz, Barbara S

    2014-06-01

    Life-long neurogenesis is a characteristic feature of many vertebrate and invertebrate species. In decapod crustaceans, new neurons are added throughout life to two cell clusters containing local (cluster 9) and projection (cluster 10) interneurons in the olfactory pathway. Adult-born neurons in clusters 9 and 10 in crayfish have the anatomical properties and chemistry of mature neurons by 6 months after birth. Here we use 5-bromo-2'-deoxyuridine (BrdU) incorporation to pulse label mitotically active cells in these cell clusters, followed by a survival time of up to 8 months, during which crayfish (Cherax destructor) were sacrificed at intervals and the numbers of BrdU-labeled cells quantified. We find a decrease in the numbers of BrdU-labeled cells in cell cluster 10 between the first and second weeks following BrdU exposure, suggesting a period of cell death shortly after proliferation. Additional delayed cell divisions in both cell clusters are indicated by increases in labeled cells long after the BrdU clearing time. The differentiation time of these cells into neurons was defined by detection of the first immunoreactivity for the transmitter SIFamide in cluster 10 BrdU-labeled cells, which begins at 4 weeks after BrdU labeling; the numbers of SIFamide-labeled cells continues to increase over the following month. Experiments testing whether proliferation and survival of Cluster 10 cells are influenced by locomotor activity provided no evidence of a correlation between activity levels and cell proliferation, but suggest a strong influence of locomotor activity on cell survival. PMID:24339155

  5. HAG regimen improves survival in adult patients with hypocellular acute myeloid leukemia

    PubMed Central

    Wang, Libing; Gao, Lei; Lü, Shuqin; Xi, Hao; Qiu, Huiying; Chen, Li; Chen, Jie; Ni, Xiong; Xu, Xiaoqian; Zhang, Weiping; Yang, Jianmin; Wang, Jianmin; Song, Xianmin

    2016-01-01

    Background Hypocellular acute myeloid leukemia (Hypo-AML) is a rare disease entity. Studies investigating the biological characteristics of hypo-AML have been largely lacking. We examined the clinical and biological characteristics, as well as treatment outcomes of hypo-AML in our institutes over a seven years period. Design and Methods We retrospectively analyzed data on 631 adult AML patients diagnosed according to the French-American-British (FAB) classification and WHO classification of tumors of haematopoietic and lymphoid tissue, including 43 patients with hypo-AML. Biological variables, treatment outcomes and follow-up data on hypo-AML patients were analyzed. Results Out of 631 AML patients, 47 (7.4%) were diagnosed as hypo-AML, out of which 43 patients were evaluable. Compared with non-hypocellular AML, hypo-AML patients tended to be older (P = 0.05), more likely to present with leukocytopenia (P < 0.01) and anterior hematological diseases (P = 0.02). The overall complete remission (CR) rate, disease free survival (DFS), and overall survival (OS) in hypo-AML patients were comparable to those in non-hypo AML patients. Twenty-seven (62.8%) patients with hypocellular AML were treated with the standard regimen of anthracyclines and cytarabine (XA) (associated CR rate: 51.9%; median OS: 7 months; median DFS: 6.5 months). Sixteen (37.2%) patients were treated with a priming regimen containing homoharringtonine, cytarabine and G-CSF (HAG) (associated CR rate: 81.25%; median OS: 16 months; median DFS: 16 months). Conclusions The overall prognosis of hypo-AML was not inferior to that of non-hypo AML. HAG regimen might increase response rates and improve survival in hypo-AML patients. PMID:26497216

  6. Demographic, Psychological, and Social Characteristics of Self-Identified Lesbian, Gay, and Bisexual Adults in a US Probability Sample

    PubMed Central

    Norton, Aaron T.; Allen, Thomas J.; Sims, Charles L.

    2010-01-01

    Using data from a US national probability sample of self-identified lesbian, gay, and bisexual adults (N = 662), this article reports population parameter estimates for a variety of demographic, psychological, and social variables. Special emphasis is given to information with relevance to public policy and law. Compared with the US adult population, respondents were younger, more highly educated, and less likely to be non-Hispanic White, but differences were observed between gender and sexual orientation groups on all of these variables. Overall, respondents tended to be politically liberal, not highly religious, and supportive of marriage equality for same-sex couples. Women were more likely than men to be in a committed relationship. Virtually all coupled gay men and lesbians had a same-sex partner, whereas the vast majority of coupled bisexuals were in a heterosexual relationship. Compared with bisexuals, gay men and lesbians reported stronger commitment to a sexual-minority identity, greater community identification and involvement, and more extensive disclosure of their sexual orientation to others. Most respondents reported experiencing little or no choice about their sexual orientation. The importance of distinguishing among lesbians, gay men, bisexual women, and bisexual men in behavioral and social research is discussed. PMID:20835383

  7. Prognostic Factors on the Graft-versus-Host Disease-Free and Relapse-Free Survival after Adult Allogeneic Hematopoietic Stem Cell Transplantation

    PubMed Central

    Liu, Yao-Chung; Chien, Sheng-Hsuan; Fan, Nai-Wen; Hu, Ming-Hung; Gau, Jyh-Pyng; Liu, Chia-Jen; Yu, Yuan-Bin; Hsiao, Liang-Tsai; Chiou, Tzeon-Jye; Tzeng, Cheng-Hwai; Chen, Po-Min; Liu, Jin-Hwang

    2016-01-01

    The cure of hematologic disorders by allogeneic hematopoietic stem cell transplantation (HSCT) is often associated with major complications resulting in poor outcome, including graft-versus-host disease (GVHD), relapse, and death. A novel composite endpoint of GVHD-free/relapse-free survival (GRFS) in which events include grades 3-4 acute GVHD, chronic GVHD requiring systemic therapy, relapse, or death is censored to completely characterize the survival without mortality or ongoing morbidity. In this regard, studies attempting to identify the prognostic factors of GRFS are quite scarce. Thus, we reviewed 377 adult patients undergoing allogeneic HSCT between 2003 and 2013. The 1- and 2-year GRFS were 40.8% and 36.5%, respectively, significantly worse than overall survival and disease-free survival (log-rank p < 0.001). European Group for Blood and Marrow Transplantation (EBMT) risk score > 2 (p < 0.001) and hematologic malignancy (p = 0.033) were poor prognostic factors for 1-year GRFS. For 2-year GRFS, EBMT risk score > 2 (p < 0.001), being male (p = 0.028), and hematologic malignancy (p = 0.010) were significant for poor outcome. The events between 1-year GRFS and 2-year GRFS predominantly increased in relapsed patients. With prognostic factors of GRFS, we could evaluate the probability of real recovery following HSCT without ongoing morbidity. PMID:27123006

  8. Long-term survival in laparoscopic vs open resection for colorectal liver metastases: inverse probability of treatment weighting using propensity scores

    PubMed Central

    Lewin, Joel W.; O'Rourke, Nicholas A.; Chiow, Adrian K.H.; Bryant, Richard; Martin, Ian; Nathanson, Leslie K.; Cavallucci, David J.

    2015-01-01

    Background This study compares long-term outcomes between intention-to-treat laparoscopic and open approaches to colorectal liver metastases (CLM), using inverse probability of treatment weighting (IPTW) based on propensity scores to control for selection bias. Method Patients undergoing liver resection for CLM by 5 surgeons at 3 institutions from 2000 to early 2014 were analysed. IPTW based on propensity scores were generated and used to assess the marginal treatment effect of the laparoscopic approach via a weighted Cox proportional hazards model. Results A total of 298 operations were performed in 256 patients. 7 patients with planned two-stage resections were excluded leaving 284 operations in 249 patients for analysis. After IPTW, the population was well balanced. With a median follow up of 36 months, 5-year overall survival (OS) and recurrence-free survival (RFS) for the cohort were 59% and 38%. 146 laparoscopic procedures were performed in 140 patients, with weighted 5-year OS and RFS of 54% and 36% respectively. In the open group, 138 procedures were performed in 122 patients, with a weighted 5-year OS and RFS of 63% and 38% respectively. There was no significant difference between the two groups in terms of OS or RFS. Conclusion In the Brisbane experience, after accounting for bias in treatment assignment, long term survival after LLR for CLM is equivalent to outcomes in open surgery. PMID:26902138

  9. Prevalence of parasitism and adult survival time of Aedes albifasciatus (Diptera: Culicidae) parasitized by Strelkovimermis spiculatus (Nematoda: Mermithidae).

    PubMed

    Di Battista, Cristian M; Fischer, Sylvia; Campos, Raúl E

    2015-12-01

    We described the carryover of Strelkovimermis spiculatus (Poinar and Camino) (Nematoda: Mermithidae) from mosquito larvae, the primary site of maturation, to adults. We analyzed the survival time of male and female Aedes albifasciatus (Macquart) (Diptera: Culicidae) parasitized by S. spiculatus, the time of emergence of nematodes from adult mosquitoes, and the state of parasitism in the same mosquito cohorts during the immature stages. Mosquito larvae with single and multiple parasitism (up to 11 parasites) were observed. The mortality of mosquito larvae and adults was produced in all cases where at least one mermithid emerged. The mortality of S. spiculatus showed an increasing trend in mosquito larvae with larger numbers of nematodes and was higher in larvae parasitized by eight or more nematodes. Maximum survival of parasitized adult females of Ae. albifasciatus was 38 days, while non-parasitized adult males and females survived 39 and 41 days, respectively. Strelkovimermis spiculatus mortality was observed in Ae. albifasciatus larvae with single or multiple parasitisms. The spread of mermithid parasitism in adult mosquito populations is discussed. PMID:26611976

  10. Survival in patients with acute myeloblastic leukemia in Germany and the United States: Major differences in survival in young adults.

    PubMed

    Pulte, Dianne; Jansen, Lina; Castro, Felipe A; Krilaviciute, Agne; Katalinic, Alexander; Barnes, Benjamin; Ressing, Meike; Holleczek, Bernd; Luttmann, Sabine; Brenner, Hermann

    2016-09-15

    Previous epidemiologic studies on AML have been limited by the rarity of the disease. Here, we present population level data on survival of patients with AML in Germany and the United States (US). Data were extracted from 11 population-based cancer registries in Germany and the Surveillance, Epidemiology, and End Results (SEER13) database in the US. Patients diagnosed with AML in 1997-2011 were included. Period analysis was used to estimate 5-year relative survival (RS) and trends in survival in the early 21st century. Overall 5-year age-adjusted RS for patients with AML in 2007-2011 was greater in Germany than in the US at 22.8% and 18.8%, respectively. Five-year RS was higher in Germany than in the US at all ages, with particularly large differences at ages 15-24 for whom 5-year RS was 64.3% in Germany and 55.0% in the US and 35-44, with 5-year RS estimates of 61.8% in Germany and 46.6% in the US. Most of the difference in 5-year RS was due to higher 1-year RS, with overall 1-year RS estimates of 47.0% in Germany and 38.5% in the US. A small increase in RS was observed between 2003-2005 and 2009-2011 in both countries, but no increase in survival was observed in either country for ages 75+. To our knowledge, this is the first detailed description of AML survival in Germany. Comparison to the US suggests that further analysis into risk factors for poor outcomes in AML in the US may be useful in improving survival. PMID:27176899

  11. Persistent organic pollution in a high-Arctic top predator: sex-dependent thresholds in adult survival

    PubMed Central

    Erikstad, Kjell Einar; Sandvik, Hanno; Reiertsen, Tone Kristin; Bustnes, Jan Ove; Strøm, Hallvard

    2013-01-01

    In long-lived species, any negative effect of pollution on adult survival may pose serious hazards to breeding populations. In this study, we measured concentrations of various organochlorines (OCs) (polychlorinated biphenyl and OC pesticides) in the blood of a large number of adult glaucous gulls (Larus hyperboreus) breeding on Bjørnøya (Bear Island) in the Norwegian Arctic, and modelled their local survival using capture–recapture analysis. Survival was negatively associated with concentrations of OCs in the blood. The effect of OCs was nonlinear and evident only among birds with the highest concentrations (the uppermost deciles of contamination). The threshold for depressed survival differed between the sexes, with females being more sensitive to contamination. For birds with lower OC concentration, survival was very high, i.e. at the upper range of survival rates reported from glaucous and other large gull species in other, presumably less contaminated populations. We propose two non-exclusive explanations. First, at some threshold of OC concentration, parents (especially males) may abandon reproduction to maximize their own survival. Second, high contamination of OC may eliminate the most sensitive individuals from the population (especially among females), inducing a strong selection towards high-quality and less sensitive phenotypes. PMID:23966640

  12. Adult tree swallow survival on the polychlorinated biphenyl-contaminated Hudson River, New York, USA, between 2006 and 2010

    USGS Publications Warehouse

    Custer, Christine M.; Custer, Thomas W.; Hines, James E.

    2012-01-01

    The upper Hudson River basin in east central New York, USA, is highly contaminated, primarily with polychlorinated biphenyls (PCBs). Reduced adult survival has been documented in tree swallows (Tachycineta bicolor) at a similarly PCB-contaminated river system in western Massachusetts. The purpose of the present study was to assess whether adult survival of tree swallows was likewise affected in the Hudson River basin. Between 2006 and 2010, a total of 521 female tree swallows were banded, of which 148 were retrapped at least once. The authors used Program MARK and an information theoretic approach to test the hypothesis that PCB contamination reduced annual survival of female tree swallows. The model that best described the processes that generated the capture history data included covariate effects of year and female plumage coloration on survival but not PCB/river. Annual survival rates of brown-plumaged females (mostly one year old) were generally lower (mean phi = 0.39) than those of blue-plumaged females (mean phi = 0.50, one year or older). Poor early spring weather in 2007 was associated with reduced survival in both plumage-color groups compared to later years. Models with the effects of PCB exposure on survival (all ΔAICc values >5.0) received little support.

  13. Adult tree swallow survival on the polychlorinated biphenyl-contaminated Hudson River, New York, USA, between 2006 and 2010.

    PubMed

    Custer, Christine M; Custer, Thomas W; Hines, James E

    2012-08-01

    The upper Hudson River basin in east central New York, USA, is highly contaminated, primarily with polychlorinated biphenyls (PCBs). Reduced adult survival has been documented in tree swallows (Tachycineta bicolor) at a similarly PCB-contaminated river system in western Massachusetts. The purpose of the present study was to assess whether adult survival of tree swallows was likewise affected in the Hudson River basin. Between 2006 and 2010, a total of 521 female tree swallows were banded, of which 148 were retrapped at least once. The authors used Program MARK and an information theoretic approach to test the hypothesis that PCB contamination reduced annual survival of female tree swallows. The model that best described the processes that generated the capture history data included covariate effects of year and female plumage coloration on survival but not PCB/river. Annual survival rates of brown-plumaged females (mostly one year old) were generally lower (mean phi=0.39) than those of blue-plumaged females (mean phi=0.50, one year or older). Poor early spring weather in 2007 was associated with reduced survival in both plumage-color groups compared to later years. Models with the effects of PCB exposure on survival (all ΔAICc values >5.0) received little support. PMID:22639085

  14. Relative abundance, site fidelity, and survival of adult lake trout in Lake Michigan from 1999 to 2001: Implications for future restoration strategies

    USGS Publications Warehouse

    Bronte, C.R.; Holey, M.E.; Madenjian, C.P.; Jonas, J.L.; Claramunt, R.M.; McKee, P.C.; Toneys, M.L.; Ebener, M.P.; Breidert, B.; Fleischer, G.W.; Hess, R.; Martell, A.W.; Olsen, E.J.

    2007-01-01

    We compared the relative abundance of lake trout Salvelinus namaycush spawners in gill nets during fall 1999–2001 in Lake Michigan at 19 stocked spawning sites with that at 25 unstocked sites to evaluate how effective site-specific stocking was in recolonizing historically important spawning reefs. The abundance of adult fish was higher at stocked onshore and offshore sites than at unstocked sites. This suggests that site-specific stocking is more effective at establishing spawning aggregations than relying on the ability of hatchery-reared lake trout to find spawning reefs, especially those offshore. Spawner densities were generally too low and too young at most sites to expect significant natural reproduction. However, densities were sufficiently high at some sites for reproduction to occur and therefore the lack of recruitment was attributable to other factors. Less than 3% of all spawners could have been wild fish, which indicates that little natural reproduction occurred in past years. Wounding by sea lamprey Petromyzon marinus was generally lower for Seneca Lake strain fish and highest for strains from Lake Superior. Fish captured at offshore sites in southern Lake Michigan had the lowest probability of wounding, while fish at onshore sites in northern Lake Michigan had the highest probability. The relative survival of the Seneca Lake strain was higher than that of the Lewis Lake or the Marquette strains for the older year-classes examined. Survival differences among strains were less evident for younger year-classes. Recaptures of coded-wire-tagged fish of five strains indicated that most fish returned to their stocking site or to a nearby site and that dispersal from stocking sites during spawning was about 100 km. Restoration strategies should rely on site-specific stocking of lake trout strains with good survival at selected historically important offshore spawning sites to increase egg deposition and the probability of natural reproduction in Lake

  15. Studies on survival and water balance of unfed adult Dermacentor marginatus and D. reticulatus ticks (Acari: Ixodidae).

    PubMed

    Meyer-König, A; Zahler, M; Gothe, R

    2001-01-01

    The water content, the survival time at various relative humidities (r.h.) and the critical equilibrium activity of unfed adult Dermacentor marginatus and D. reticulatus ticks were investigated at a constant temperature of 20 degrees C. It was also examined whether these ticks use liquid water to compensate water loss. Both Dermacentor spp. showed no significant differences in water content in relation to body mass. The mean water content of D. marginatus and D. reticulatus was 54.6% and 54.7%, respectively, in females and 56.3% and 57.0%, respectively, in males. The survival time of unfed adults prolonged with decreasing saturation deficits. On average, males survived longer than females and D. marginatus ticks survived mostly longer than D. reticulatus ticks. The 50% mortality period ranged between 40 d at 33% r.h. and 420 d at 95% r.h. in D. marginatus, and between 43 d at 33 r.h. and 366 d at 95% r.h. in D. reticulatus. The critical equilibrium activity of unfed adults was estimated to be 0.84 for both species and was independent of sex. When dehydrated adult D. marginatus and D. reticulatus ticks were offered liquid water, only a few slightly gained weight while most further lost weight. Liquid water was not attractive for dehydrated or non-dehydrated ticks and drinking was not observed. After submerging in water for 2 d, most of the dehydrated ticks had gained weight. PMID:12465853

  16. Late summer survival of adult female and juvenile spectacled eiders on the Yukon-Kuskokwim Delta, Alska

    USGS Publications Warehouse

    Flint, P.L.; Barry, Grand J.; Morse, J.A.; Fondell, T.F.

    2000-01-01

    We used radio-telemetry to examine survival of adult female and juvenile Spectacled Eiders (Somateria fischeri) from 30 days after hatch until departure from the Yukon-Kuskokwim Delta (YKD) during 1997-1999. Juvenile survival was 71.4%; adult female survival was 88.5%. Mink (Mustella vison) were the most common predator identified for both adults and juveniles. Detectable levels of lead were found in bones of 74% of juvenile carcasses recovered and 21% had levels indicative of acute exposure. Average age at departure was 59 ?? 1 days old for juveniles and 56 ?? 1 days after hatch for adults. Most broods (60.5%) departed the YKD synchronously. Overall our data indicate that mortality during the latter half of brood-rearing is higher than previously thought. We conclude that brood rearing is a period of high mortality for brood-rearing females and that lead poisoning is responsible for reductions in juvenile survival to fledging. Received 15 February 2000, accepted 1 April 2000.

  17. Survival of Lactobacillus casei strain Shirota in the intestines of healthy Chinese adults.

    PubMed

    Wang, Ran; Chen, Shanbin; Jin, Junhua; Ren, Fazheng; Li, Yang; Qiao, Zhenxing; Wang, Yue; Zhao, Liang

    2015-05-01

    Lactobacillus casei strain Shirota (LcS) is a widely used probiotic strain with health benefits. In this study, the survival of LcS in the intestines of healthy Chinese adults was assessed and the effects of LcS on stool consistency, stool SCFAs and intestinal microbiota evaluated. Subjects consumed 100 mL per day of a probiotic beverage containing 1.0 × 10(8) CFU/mL of LcS for 14 days. LcS were enumerated using a culture method and the colony identity confirmed by ELISA. Fourteen days after ingestion, the amount of LcS recovered from fecal samples was between 6.86 ± 0.80 and 7.17 ± 0.57 Log10 CFU/g of feces (mean ± SD). The intestinal microbiotas were analyzed by denaturing gradient gel electrophoresis. Principal component analysis showed that consuming LcS significantly changed fecal microbiota profiles. According to redundancy analysis, the amounts of 25 bacterial strains were significantly correlated with LcS intake (P < 0.05), 11 of them positively and fourteen negatively. Concentrations of acetic acid and propionic acid in feces were significantly lower during the ingestion period than during the baseline period (P < 0.05). These results confirm that LcS can survive passage through the gastrointestinal tract of Chinese people; however, they were found to have little ability to persist once their consumption had ceased. Furthermore, consumption of probiotic beverages containing LcS can modulate the composition of the intestinal microbiota on a long-term basis, resulting in decreased concentrations of SCFAs in the gut. PMID:25707300

  18. Social Structural Influences on Healthy Aging: Community-Level Socioeconomic Conditions and Survival Probability of Becoming a Centenarian for Those Aged 65 to 69 in South Korea.

    PubMed

    Kim, Jong In; Kim, Gukbin

    2015-10-01

    This study estimated the associations between community-level socioeconomic conditions and survival probability of becoming a centenarian (SPBC) for those aged 65 to 69 in South Korea to determine the social structural influences on healthy aging. The indicators of socioeconomic and data of centenarians were obtained from Statistics Korea database 2014: population census and social survey. Significant positive correlations were found between SPBC and community-level socioeconomic conditions (minimum cost of living and economically active population, water supply and sewerage, pave a road with asphalt, and urbanization). SPBC male and female predictors had higher economic level and base facilities (R2)=0.578, p<.001). The study provides evidence that community-level socioeconomic conditions are important correlates of SPBC for those aged 65 to 69 in South Korea. These strategies should include social structural influences on successful aging in the overall socioeconomic conditions. PMID:26769915

  19. Postnatal growth rates covary weakly with embryonic development rates and do not explain adult mortality probability among songbirds on four continents.

    PubMed

    Martin, Thomas E; Oteyza, Juan C; Mitchell, Adam E; Potticary, Ahva L; Lloyd, Penn

    2015-03-01

    Growth and development rates may result from genetic programming of intrinsic processes that yield correlated rates between life stages. These intrinsic rates are thought to affect adult mortality probability and longevity. However, if proximate extrinsic factors (e.g., temperature, food) influence development rates differently between stages and yield low covariance between stages, then development rates may not explain adult mortality probability. We examined these issues based on study of 90 songbird species on four continents to capture the diverse life-history strategies observed across geographic space. The length of the embryonic period explained little variation (ca. 13%) in nestling periods and growth rates among species. This low covariance suggests that the relative importance of intrinsic and extrinsic influences on growth and development rates differs between stages. Consequently, nestling period durations and nestling growth rates were not related to annual adult mortality probability among diverse songbird species within or among sites. The absence of a clear effect of faster growth on adult mortality when examined in an evolutionary framework across species may indicate that species that evolve faster growth also evolve physiological mechanisms for ameliorating costs on adult mortality. Instead, adult mortality rates of species in the wild may be determined more strongly by extrinsic environmental causes. PMID:25674692

  20. Postnatal growth rates covary weakly with embryonic development rates and do not explain adult mortality probability among songbirds on four continents

    USGS Publications Warehouse

    Martin, Thomas E.; Oteyza, Juan C.; Mitchell, Adam E.; Potticary, Ahva L.; Lloyd, P.

    2016-01-01

    Growth and development rates may result from genetic programming of intrinsic processes that yield correlated rates between life stages. These intrinsic rates are thought to affect adult mortality probability and longevity. However, if proximate extrinsic factors (e.g., temperature, food) influence development rates differently between stages and yield low covariance between stages, then development rates may not explain adult mortality probability. We examined these issues based on study of 90 songbird species on four continents to capture the diverse life-history strategies observed across geographic space. The length of the embryonic period explained little variation (ca. 13%) in nestling periods and growth rates among species. This low covariance suggests that the relative importance of intrinsic and extrinsic influences on growth and development rates differs between stages. Consequently, nestling period durations and nestling growth rates were not related to annual adult mortality probability among diverse songbird species within or among sites. The absence of a clear effect of faster growth on adult mortality when examined in an evolutionary framework across species may indicate that species that evolve faster growth also evolve physiological mechanisms for ameliorating costs on adult mortality. Instead, adult mortality rates of species in the wild may be determined more strongly by extrinsic environmental causes.

  1. Survival and preference of cotton boll weevil adults for alternative food sources.

    PubMed

    Pimenta, M; Mata, R A; Venzon, M; Cunha, D N C; Fontes, E M G; Pires, C S S; Sujii, E R

    2016-06-01

    Plants that have potential as alternative food source (floral nectar, pollen and plant tissues) to the boll weevil during the intercropping season were evaluated considering the prevalent conditions of Cerrado in the Central Brazil. Initially, we tested the nutritional adequacy for the survival of the insect of flower resource (pollen and nectar) provided by eight plant species (fennel, mexican sunflower, castor bean, okra, hibiscus, sorghum, pigeonpea and sunn hemp). Subsequently, we tested if the resources provided by the selected plants continued to be exploited by the boll weevil in the presence of cotton plant, its main food source average longevity of boll weevil adults was significantly longer when they were fed on hibiscus' flowers (166.6 ± 74.4) and okra flowers (34.7 ± 28.9) than when they fed on flowers of other six species. Subsequently, the preference of the boll weevil in the use of resources was compared between okra or hibiscus and cotton plants, in dual choice experiments. Boll weevils preferred plants of the three species in the reproductive stages than those in vegetative stages. Although the cotton plant in the reproductive stage was the most preferred plant of all, boll weevils preferred flowering okra and hibiscus than cotton at the vegetative stage. PMID:26934148

  2. Telomerase Gene (hTERT) and Survival: Results From Two Swedish Cohorts of Older Adults.

    PubMed

    Kalpouzos, Grégoria; Rizzuto, Debora; Keller, Lina; Fastbom, Johan; Santoni, Giola; Angleman, Sara; Graff, Caroline; Bäckman, Lars; Fratiglioni, Laura

    2016-02-01

    Telomere length has been associated with longevity. As telomere length is partly determined by the human telomerase reverse transcriptase (hTERT), we investigated the association between an hTERT polymorphism located in its promoter region ((-) (1327)T/C) and longevity in two cohorts of older adults. Participants from the Kungsholmen project (KP; n = 1,205) and the Swedish National study of Aging and Care in Kungsholmen (SNAC-K; n = 2,764) were followed for an average period of 7.5 years. The main outcomes were hazard ratios (HR) of mortality and median age at death. In both cohorts, mortality was lower in female T/T carriers, aged 75+ years in KP (HR = 0.8, 95% CI: 0.5-0.9) and 78+ years in SNAC-K (HR = 0.6, 95% CI: 0.4-0.8) compared with female C/C carriers. T/T carriers died 1.8-3 years later than the C/C carriers. This effect was not present in men, neither in SNAC-K women aged 60-72 years. The association was not modified by presence of cancer, cardiovascular diseases, number of chronic diseases, or markers of inflammation, and did not interact with APOE genotype or estrogen replacement therapy. The gender-specific increased survival in T/T carriers can be due to a synergistic effect between genetic background and the life-long exposure to endogenous estrogen. PMID:25452402

  3. Hate Crimes and Stigma-Related Experiences among Sexual Minority Adults in the United States: Prevalence Estimates from a National Probability Sample

    ERIC Educational Resources Information Center

    Herek, Gregory M.

    2009-01-01

    Using survey responses collected via the Internet from a U.S. national probability sample of gay, lesbian, and bisexual adults (N = 662), this article reports prevalence estimates of criminal victimization and related experiences based on the target's sexual orientation. Approximately 20% of respondents reported having experienced a person or…

  4. Prognostic factors and survival in late adolescent and adult patients with small round cell tumors.

    PubMed

    Eralp, Yeşim; Bavbek, Sevil; Başaran, Mert; Kaytan, Esra; Yaman, Fulya; Bilgiç, Bilge; Darendeliler, Emin; Onat, Haluk

    2002-08-01

    The primary objective of this study is to review the clinical characteristics of 25 patients in the adult and late adolescent age group, diagnosed and treated with small round cell tumors involving soft tissues (extraosseous Ewing sarcoma, rhabdo-myosarcoma, primitive neuroectodermal tumor, and undiffer-entiated small round cell tumors). Additionally, survival and prognostic factors influencing the outcome with multimodality treatment are evaluated. There were 19 males (76%) and 6 females (24%). The median age was 26 years (range: 15-56 years). In 9 patients (36%), the tumor was located at an extremity, whereas 16 patients (64%) had central localizations. Tumor size was larger than 10 cm in 7 patients (29.2%). Six patients (24%) had metastatic disease. Twelve patients (48%) received radiation and 16 patients (64%) underwent surgery. Among the resected tumors, 2 were resected with contaminated margins (12.5%), whereas 2 were radically resected and 12 (75%) were resected with wide margins. All patients were given a median of 4 cycles of multiagent chemotherapy (1-14 cycles). With preoperative chemotherapy, complete regression (CR) of the tumor was achieved in 6 patients (24%). In 4 patients (16%), a partial response was obtained. After the completion of multimodality treatment, 12 patients (48%) had a CR. Progression-free (PFS) and overall survival (OS) for the entire group was 25.0 +/- 10.8% at 1 year and 30.5 +/- 15.5% at 3 years, respectively. Nonmetastatic disease, wide and radical resection, and presence of CR to multimodality treatment were associated with a significantly longer PFS and OS by univariate analysis. By multivariate analysis, CR to multimodality treat-ment was the only independent predictive factor for a longer OS (p: 0.0036, relative risk [RR]: 23.6, 95% CI: 2.8; 198.7) and metastatic presentation was the only independent factor predic-tive for a shorter PFS (p: 0.017, RR. 15, 95% CI: 1.6; 141.2). Large-scale, multicenter studies are required for

  5. Overwintering, Oviposition, and Larval Survival of Hunting Billbugs (Coleoptera: Curculionidae) and Implications for Adult Damage in North Carolina Turfgrass.

    PubMed

    Reynolds, Diane Silcox; Reynolds, William Casey; Brandenburg, Rick L

    2016-02-01

    The hunting billbug, Sphenophorus venatus vestitus Chittenden, is one of the most widely recognized billbug turfgrass pests. Since 2000, damage to warm-season turfgrass caused by hunting bill bugs has increased and a need for information on hunting billbug biology is necessary for the development of management plans. Field and laboratory studies were conducted to collect data on overwintering, oviposition behavior, larval survival at various levels of soil moisture, and adult damage. Turfgrass samples from ‘Tifway 419’ bermudagrass(Cynodon dactylon (L.) Pers x Cynodon transvaalensis Burtt Davy) on golf courses were collected to determine overwintering behavior, and 10 female adult billbugs were collected weekly to determine oviposition behavior.Survival of medium-sized larvae (head capsule width: 1.0 and 1.7 mm) was evaluated in containers with 20, 40,60, or 80% of the total pore space occupied by water. Zero, two, four, or six adult billbugs were placed in bermudagrass, zoysiagrass, or tall fescue containers and images were collected for 4 weeks to determine adult damage. We observed that hunting billbugs overwinter as adults and all larval sizes. Adults became active in March and began to oviposit, which continued through October. Larval mortality was lowest with 20% of the total pores pace occupied by water, while increases in moisture caused significant mortality. Adults caused a greater reduction in warm-season turfgrass cover than cool-season turfgrass cover. This research builds on the existing biological information for the hunting billbug biology in transition zones and will be pivotal in developing practical and sustainable management plans. PMID:26567333

  6. Prolonged survival in adult neurofibromatosis type I patients with recurrent high-grade gliomas treated with bevacizumab.

    PubMed

    Theeler, Brett J; Ellezam, Benjamin; Yust-Katz, Shlomit; Slopis, John M; Loghin, Monica E; de Groot, John F

    2014-08-01

    Astrocytic tumors, especially optic pathway pilocytic astrocytomas, are common in pediatric NF1 patients. High-grade gliomas (HGGs) appear to be rare in adult and pediatric NF1 patients. This is a series of five consecutive, adult NF1 patients with recurrent HGGs treated at The University of Texas MD Anderson Cancer Center. Four patients met consensus clinical criteria for NF1 and one patient had presumed segmental NF1. Three patients had glioblastomas, one gliosarcoma, and one progressive, enhancing optic pathway glioma which was not biopsied. Two tumors had molecular testing performed; both were IDH wild type and activating oncogene mutations (1 BRAFV600E and 1 PIK3CA mutation) were found in these tumors. All five patients received bevacizumab-containing regimens at tumor recurrence. The median number of 4-week cycles of bevacizumab was 20. All five patients experienced prolonged post-recurrence survival following bevacizumab treatment ranging from ten to 72 months. The median overall survival from HGG diagnosis was 72.6 months with three patients alive and progression free at last follow-up. Three out of five patients developed vascular complications leading to bevacizumab discontinuation. In this case series, adult NF1 patients with recurrent HGGs had prolonged, post-recurrence survival after treatment with bevacizumab-containing regimens. Based on these results, further study of antiangiogenic therapy in NF1 patients with HGGs and bevacizumab-response in sporadic HGG patients with NF1-mutated tumors is warranted. PMID:24859329

  7. Determination of the compound nucleus survival probability Psurv for various "hot" fusion reactions based on the dynamical cluster-decay model

    NASA Astrophysics Data System (ADS)

    Chopra, Sahila; Kaur, Arshdeep; Gupta, Raj K.

    2015-03-01

    After a successful attempt to define and determine recently the compound nucleus (CN) fusion/ formation probability PCN within the dynamical cluster-decay model (DCM), we introduce and estimate here for the first time the survival probability Psurv of CN against fission, again within the DCM. Calculated as the dynamical fragmentation process, Psurv is defined as the ratio of the evaporation residue (ER) cross section σER and the sum of σER and fusion-fission (ff) cross section σff, the CN formation cross section σCN, where each contributing fragmentation cross section is determined in terms of its formation and barrier penetration probabilities P0 and P . In DCM, the deformations up to hexadecapole and "compact" orientations for both in-plane (coplanar) and out-of-plane (noncoplanar) configurations are allowed. Some 16 "hot" fusion reactions, forming a CN of mass number ACN˜100 to superheavy nuclei, are analyzed for various different nuclear interaction potentials, and the variation of Psurv on CN excitation energy E*, fissility parameter χ , CN mass ACN, and Coulomb parameter Z1Z2 is investigated. Interesting results are that three groups, namely, weakly fissioning, radioactive, and strongly fissioning superheavy nuclei, are identified with Psurv, respectively, ˜1 ,˜10-6 , and ˜10-10 . For the weakly fissioning group (100

  8. Behavioural Effects of Adult Vitamin D Deficiency in BALB/c Mice Are not Associated with Proliferation or Survival of Neurons in the Adult Hippocampus

    PubMed Central

    Groves, Natalie J.; Bradford, DanaKai; Sullivan, Robert K. P.; Conn, Kyna-Anne; Aljelaify, Rasha Fahad; McGrath, John J.; Burne, Thomas H. J.

    2016-01-01

    Epidemiological studies have shown that up to one third of adults have insufficient levels of vitamin D and there is an association between low vitamin D concentrations and adverse brain outcomes, such as depression. Vitamin D has been shown to be involved in processes associated with neurogenesis during development. Therefore, the aim of this study was to test the hypothesis that adult vitamin D (AVD) deficiency in BALB/c mice was associated with (a) adult hippocampal neurogenesis at baseline, b) following 6 weeks of voluntary wheel running and (c) a depressive-like phenotype on the forced swim test (FST), which may be linked to alterations in hippocampal neurogenesis. We assessed proliferation and survival of adult born hippocampal neurons by counting the number of cells positive for Ki67 and doublecortin (DCX), and incorporation of 5-Bromo-2’-Deoxyuridine (BrdU) within newly born mature neurons using immunohistochemistry. There were no significant effects of diet on number of Ki67+, DCX+ or BrdU+ cells in the dentate gyrus. All mice showed significantly increased number of Ki67+ cells and BrdU incorporation, and decreased immobility time in the FST, after voluntary wheel running. A significant correlation was found in control mice between immobility time in the FST and level of hippocampal neurogenesis, however, no such correlation was found for AVD-deficient mice. We conclude that AVD deficiency was not associated with impaired proliferation or survival of adult born neurons in BALB/c mice and that the impact on rodent behaviour may not be due to altered neurogenesis per se, but to altered function of new hippocampal neurons or processes independent of adult neurogenesis. PMID:27043014

  9. Behenoyl cytosine arabinoside, daunorubicin, 6-mercaptopurine, and prednisolone combination therapy for acute myelogenous leukemia in adults and prognostic factors related to remission duration and survival length.

    PubMed

    Ohno, R; Kato, Y; Nagura, E; Murase, T; Okumura, M; Yamada, H; Ogura, M; Minami, S; Suzuki, H; Morishima, Y

    1986-12-01

    Fifty-one consecutive previously untreated adult patients with acute myelogenous leukemia (AML) were treated with BHAC-DMP (N4-behenoyl-I-beta-D-arabinofuranosyl-cytosine, daunorubicin, 6-mercaptopurine, and prednisolone) therapy. Forty-two patients (82.4%) achieved complete remission (CR). The Kaplan-Meier analysis revealed a probability for remaining in remission of 14% and for survival of 23% at 6 years. Pretreatment factors related to the achievement of CR, such as age, French-American-British (FAB) classification and WBC at the start of treatment, were not identified. Factors related to the CR duration and survival time of the patients who had achieved CR were first analyzed by a univariate analysis with the generalized Wilcoxon test. WBC count at the start of treatment, percent of blasts in the marrow at 1 and 2 weeks after the initiation of therapy, days required until CR, number of courses of induction therapy required until CR, and days required for the disappearance of circulating blasts were identified as statistically significant prognostic factors. When these characteristics were further analyzed by the Cox multivariate regression model, the percent of blasts in the bone marrow at 2 weeks was the most important prognostic factor with a statistical significance, and WBC count at the start of treatment and days required until CR (or number of courses required to achieve CR) were also important factors, with borderline significance. PMID:3465875

  10. Smad3 is required for the survival of proliferative intermediate progenitor cells in the dentate gyrus of adult mice

    PubMed Central

    2013-01-01

    Background New neurons are continuously being generated in the adult hippocampus, a phenomenon that is regulated by external stimuli, such as learning, memory, exercise, environment or stress. However, the molecular mechanisms underlying neuron production and how they are integrated into existing circuits under such physiological conditions remain unclear. Indeed, the intracellular modulators that transduce the extracellular signals are not yet fully understood. Results We show that Smad3, an intracellular molecule involved in the transforming growth factor (TGF)-β signaling cascade, is strongly expressed by granule cells in the dentate gyrus (DG) of adult mice, although the loss of Smad3 in null mutant mice does not affect their survival. Smad3 is also expressed by adult progenitor cells in the subgranular zone (SGZ) and more specifically, it is first expressed by Type 2 cells (intermediate progenitor cells). Its expression persists through the distinct cell stages towards that of the mature neuron. Interestingly, proliferative intermediate progenitor cells die in Smad3 deficiency, which is associated with a large decrease in the production of newborn neurons in Smad3 deficient mice. Smad3 signaling appears to influence adult neurogenesis fulfilling distinct roles in the rostral and mid-caudal regions of the DG. In rostral areas, Smad3 deficiency increases proliferation and promotes the cell cycle exit of undifferentiated progenitor cells. By contrast, Smad3 deficiency impairs the survival of newborn neurons in the mid-caudal region of the DG at early proliferative stages, activating apoptosis of intermediate progenitor cells. Furthermore, long-term potentiation (LTP) after high frequency stimulation (HFS) to the medial perforant path (MPP) was abolished in the DG of Smad3-deficient mice. Conclusions These data show that endogenous Smad3 signaling is central to neurogenesis and LTP induction in the adult DG, these being two forms of hippocampal brain plasticity

  11. Supratentorial hemispheric ependymomas: an analysis of 109 adults for survival and prognostic factors.

    PubMed

    Hollon, Todd; Nguyen, Vincent; Smith, Brandon W; Lewis, Spencer; Junck, Larry; Orringer, Daniel A

    2016-08-01

    OBJECTIVE Survival rates and prognostic factors for supratentorial hemispheric ependymomas have not been determined. The authors therefore designed a retrospective study to determine progression-free survival (PFS), overall survival (OS), and prognostic factors for hemispheric ependymomas. METHODS The study population consisted of 8 patients from our institution and 101 patients from the literature with disaggregated survival information (n = 109). Patient age, sex, tumor side, tumor location, extent of resection (EOR), tumor grade, postoperative chemotherapy, radiation, time to recurrence, and survival were recorded. Kaplan-Meier survival analyses and Cox proportional hazard models were completed to determine survival rates and prognostic factors. RESULTS Anaplastic histology/WHO Grade III tumors were identified in 62% of cases and correlated with older age. Three-, 5-, and 10-year PFS rates were 57%, 51%, and 42%, respectively. Three-, 5-, and 10-year OS rates were 77%, 71%, and 58%, respectively. EOR and tumor grade were identified on both Kaplan-Meier log-rank testing and univariate Cox proportional hazard models as prognostic for PFS and OS. Both EOR and tumor grade remained prognostic on multivariate analysis. Subtotal resection (STR) predicted a worse PFS (hazard ratio [HR] 4.764, p = 0.001) and OS (HR 4.216, p = 0.008). Subgroup survival analysis of patients with STR demonstrated a 5- and 10-year OS of 28% and 0%, respectively. WHO Grade III tumors also had worse PFS (HR 10.2, p = 0.004) and OS (HR 9.1, p = 0.035). Patients with WHO Grade III tumors demonstrated 5- and 10-year OS of 61% and 46%, respectively. Postoperative radiation was not prognostic for PFS or OS. CONCLUSIONS A high incidence of anaplastic histology was found in hemispheric ependymomas and was associated with older age. EOR and tumor grade were prognostic factors for PFS and OS on multivariate analysis. STR or WHO Grade III pathology, or both, predicted worse overall prognosis in patients

  12. Design and Analysis of Salmonid Tagging Studies in the Columbia Basin, Volume VIII; New Model for Estimating Survival Probabilities and Residualization from a Release-Recapture Study of Fall Chinook Salmon Smolts in the Snake River, 1995 Technical Report.

    SciTech Connect

    Lowther, Alan B.; Skalski, John R.

    1997-09-01

    Standard release-recapture analysis using Cormack-Jolly-Seber (CJS) models to estimate survival probabilities between hydroelectric facilities for Snake River fall chinook salmon (Oncorhynchus tschawytscha) ignore the possibility of individual fish residualizing and completing their migration in the year following tagging.

  13. Sex disparity in childhood and young adult acute myeloid leukemia (AML) survival: Evidence from US population data.

    PubMed

    Hossain, Md Jobayer; Xie, Li

    2015-12-01

    Sex variation has been persistently investigated in studies concerning acute myeloid leukemia (AML) survival outcomes but has not been fully explored among pediatric and young adult AML patients. We detected sex difference in the survival of AML patients diagnosed at ages 0-24 years and explored distinct effects of sex across subgroups of age at diagnosis, race-ethnicity and AML subtypes utilizing the United States Surveillance Epidemiology and End Results (SEER) population based dataset of 4865 patients diagnosed with AML between 1973 and 2012. Kaplan-Meier survival function, propensity scores and stratified Cox proportional hazards regression were used for data analyses. After controlling for other prognostic factors, females showed a significant survival advantage over their male counterparts, adjusted hazard ratio (aHR, 95% confidence interval (CI): 1.09, 1.00-1.18). Compared to females, male patients had substantially increased risk of mortality in the following subgroups of: ages 20-24 years at diagnosis (aHR1.30), Caucasian (1.14), acute promyelocytic leukemia (APL) (1.35), acute erythroid leukemia (AEL) (1.39), AML with inv(16)(p13.1q22) (2.57), AML with minimum differentiation (1.47); and had substantially decreased aHR in AML t(9;11)(p22;q23) (0.57) and AML with maturation (0.82). Overall, females demonstrated increased survival over males and this disparity was considerably large in patients ages 20-24 years at diagnosis, Caucasians, and in AML subtypes of AML inv(16), APL and AEL. In contrast, males with AML t(9;11)(p22;q23), AML with maturation and age at diagnosis of 10-14 years showed survival benefit. Further investigations are needed to detect the biological processes influencing the mechanisms of these interactions. PMID:26520618

  14. Species differences in behavior and cell proliferation/survival in the adult brains of female meadow and prairie voles.

    PubMed

    Pan, Y; Liu, Y; Lieberwirth, C; Zhang, Z; Wang, Z

    2016-02-19

    Microtine rodents display diverse patterns of social organization and behaviors, and thus provide a useful model for studying the effects of the social environment on physiology and behavior. The current study compared the species differences and the effects of oxytocin (OT) on anxiety-like, social affiliation, and social recognition behaviors in female meadow voles (Microtus pennsylvanicus) and prairie voles (Microtus ochrogaster). Furthermore, cell proliferation and survival in the brains of adult female meadow and prairie voles were compared. We found that female meadow voles displayed a higher level of anxiety-like behavior but lower levels of social affiliation and social recognition compared to female prairie voles. In addition, meadow voles showed lower levels of cell proliferation (measured by Ki67 staining) and cell survival (measured by BrdU staining) in the ventromedial hypothalamus (VMH) and amygdala (AMY), but not the dentate gyrus of the hippocampus (DG), than prairie voles. Interestingly, the numbers of new cells in the VMH and AMY, but not DG, also correlated with anxiety-like, social affiliation, and social recognition behaviors in a brain region-specific manner. Finally, central OT treatment (200 ng/kg, icv) did not lead to changes in behavior or cell proliferation/survival in the brain. Together, these data indicate a potential role of cell proliferation/survival in selected brain areas on different behaviors between vole species with distinct life strategies. PMID:26708743

  15. The Impact of Physical, Intellectual and Social Impairments on Survival in Adults with Intellectual Disability: A Population-Based Register Study

    ERIC Educational Resources Information Center

    Tyrer, Freya; Smith, Lucy K.; McGrother, Catherine W.; Taub, Nicholas A.

    2007-01-01

    Background: Research into factors associated with survival in adults with intellectual disability is limited and no studies have controlled for changes in these factors over time. Material and Methods: All adults aged greater than or equal to 20 years with moderate to profound intellectual disability (approximate IQ less than 50) using specialist…

  16. Intertwining extracellular nucleotides and their receptors with Ca2+ in determining adult neural stem cell survival, proliferation and final fate.

    PubMed

    Lecca, Davide; Fumagalli, Marta; Ceruti, Stefania; Abbracchio, Maria P

    2016-08-01

    In the central nervous system (CNS), during both brain and spinal cord development, purinergic and pyrimidinergic signalling molecules (ATP, UTP and adenosine) act synergistically with peptidic growth factors in regulating the synchronized proliferation and final specification of multipotent neural stem cells (NSCs) to neurons, astrocytes or oligodendrocytes, the myelin-forming cells. Some NSCs still persist throughout adulthood in both specific 'neurogenic' areas and in brain and spinal cord parenchyma, retaining the potentiality to generate all the three main types of adult CNS cells. Once CNS anatomical structures are defined, purinergic molecules participate in calcium-dependent neuron-to-glia communication and also control the behaviour of adult NSCs. After development, some purinergic mechanisms are silenced, but can be resumed after injury, suggesting a role for purinergic signalling in regeneration and self-repair also via the reactivation of adult NSCs. In this respect, at least three different types of adult NSCs participate in the response of the adult brain and spinal cord to insults: stem-like cells residing in classical neurogenic niches, in particular, in the ventricular-subventricular zone (V-SVZ), parenchymal oligodendrocyte precursor cells (OPCs, also known as NG2-glia) and parenchymal injury-activated astrocytes (reactive astrocytes). Here, we shall review and discuss the purinergic regulation of these three main adult NSCs, with particular focus on how and to what extent modulation of intracellular calcium levels by purinoceptors is mandatory to determine their survival, proliferation and final fate.This article is part of the themed issue 'Evolution brings Ca(2+) and ATP together to control life and death'. PMID:27377726

  17. Winter survival of adult female harlequin ducks in relation to history of contamination by the Exxon Valdez oil spill

    USGS Publications Warehouse

    Esler, Daniel; Schmutz, J.A.; Jarvis, R.L.; Mulcahy, D.M.

    2000-01-01

    Harlequin duck (Histrionicus histrionicus) life-history characteristics make their populations particularly vulnerable to perturbations during nonbreeding periods. The 1989 Exxon Valdez oil spill was a major perturbation to nonbreeding habitats of harlequin ducks in Prince William Sound, Alaska, which resulted in population injury. To assess the status of population recovery from the oil spill and to evaluate factors potentially constraining full recovery, we used radiotelemetry to examine survival of adult female harlequin ducks during winters of 1995-96, 1996-97, and 1997-98. We implanted 294 harlequin ducks (154 and 140 in oiled and unoiled areas, respectively) with transmitters and tracked their signals from aircraft during October through March. We examined variation in survival rates relative to area and season (early, mid, and late winter) through comparisons of models using Akaike's information criterion (AIC(c)) values. The 3 models best supported by the data indicated that survival of birds in oiled areas was lower than in unoiled areas. Inclusion of standardized body mass during wing molt in the 3 best models did not improve their fit, indicating that body mass during wing molt did not affect subsequent winter survival. In the model that best fit our data, survival was high in early winter for both areas, lower during mid and late winter seasons, and lowest in oiled areas during mid winter. Cumulative winter survival estimated from this model was 78.0% (SE = 3.3%) in oiled areas and 83.7% (SE = 2.9%) in unoiled areas. We determined that area differences in survival were more likely related to oiling history than intrinsic geographic differences. Based on a demographic model, area differences in survival offer a likely mechanism for observed declines in populations on oiled areas. Concurrent studies indicated that harlequin ducks continued to be exposed to residual Exxon Valdez oil as much as 9 years after the spill. We suggest that oil exposure

  18. Factors Affecting the Survival of Upstream Migrant Adult Salmonids in the Columbia River Basin : Recovery Issues for Threatened and Endangered Snake River Salmon : Technical Report 9 of 11.

    SciTech Connect

    Dauble, Dennis D.; Mueller, Robert P.

    1993-06-01

    The Bonneville Power Administration (BPA) is developing conservation planning documentation to support the National Marine Fisheries Service`s (NMFS) recovery plan for Columbia Basin salmonid stocks that are currently listed under the Endangered Species Act (ESA). Information from the conservation planning documentation will be used as a partial scientific basis for identifying alternative conservation strategies and to make recommendations toward conserving, rebuilding, and ultimately removing these salmon stocks from the list of endangered species. This report describes the adult upstream survival study, a synthesis of biological analyses related to conditions affecting the survival of adult upstream migrant salmonids in the Columbia River system. The objective of the adult upstream survival study was to analyze existing data related to increasing the survival of adult migrant salmonids returning to the Snake River system. The fate and accountability of each stock during its upstream migration period and the uncertainties associated with measurements of escapement and survival were evaluated. Operational measures that affected the survival of adult salmon were evaluated including existing conditions, augmented flows from upstream storage release, and drawdown of mainstem reservoirs. The potential impacts and benefits of these measures to each ESA stock were, also described based on considerations of species behavior and run timing.

  19. Lmx1a and Lmx1b regulate mitochondrial functions and survival of adult midbrain dopaminergic neurons.

    PubMed

    Doucet-Beaupré, Hélène; Gilbert, Catherine; Profes, Marcos Schaan; Chabrat, Audrey; Pacelli, Consiglia; Giguère, Nicolas; Rioux, Véronique; Charest, Julien; Deng, Qiaolin; Laguna, Ariadna; Ericson, Johan; Perlmann, Thomas; Ang, Siew-Lan; Cicchetti, Francesca; Parent, Martin; Trudeau, Louis-Eric; Lévesque, Martin

    2016-07-26

    The LIM-homeodomain transcription factors Lmx1a and Lmx1b play critical roles during the development of midbrain dopaminergic progenitors, but their functions in the adult brain remain poorly understood. We show here that sustained expression of Lmx1a and Lmx1b is required for the survival of adult midbrain dopaminergic neurons. Strikingly, inactivation of Lmx1a and Lmx1b recreates cellular features observed in Parkinson's disease. We found that Lmx1a/b control the expression of key genes involved in mitochondrial functions, and their ablation results in impaired respiratory chain activity, increased oxidative stress, and mitochondrial DNA damage. Lmx1a/b deficiency caused axonal pathology characterized by α-synuclein(+) inclusions, followed by a progressive loss of dopaminergic neurons. These results reveal the key role of these transcription factors beyond the early developmental stages and provide mechanistic links between mitochondrial dysfunctions, α-synuclein aggregation, and the survival of dopaminergic neurons. PMID:27407143

  20. Nuclear factor of activated T cells (NFATc4) is required for BDNF-dependent survival of adult-born neurons and spatial memory formation in the hippocampus.

    PubMed

    Quadrato, Giorgia; Benevento, Marco; Alber, Stefanie; Jacob, Carolin; Floriddia, Elisa M; Nguyen, Tuan; Elnaggar, Mohamed Y; Pedroarena, Christine M; Molkentin, Jeffrey D; Di Giovanni, Simone

    2012-06-01

    New neurons generated in the adult dentate gyrus are constantly integrated into the hippocampal circuitry and activated during encoding and recall of new memories. Despite identification of extracellular signals that regulate survival and integration of adult-born neurons such as neurotrophins and neurotransmitters, the nature of the intracellular modulators required to transduce those signals remains elusive. Here, we provide evidence of the expression and transcriptional activity of nuclear factor of activated T cell c4 (NFATc4) in hippocampal progenitor cells. We show that NFATc4 calcineurin-dependent activity is required selectively for survival of adult-born neurons in response to BDNF signaling. Indeed, cyclosporin A injection and stereotaxic delivery of the BDNF scavenger TrkB-Fc in the mouse dentate gyrus reduce the survival of hippocampal adult-born neurons in wild-type but not in NFATc4(-/-) mice and do not affect the net rate of neural precursor proliferation and their fate commitment. Furthermore, associated with the reduced survival of adult-born neurons, the absence of NFATc4 leads to selective defects in LTP and in the encoding of hippocampal-dependent spatial memories. Thus, our data demonstrate that NFATc4 is essential in the regulation of adult hippocampal neurogenesis and identify NFATc4 as a central player of BDNF-driven prosurvival signaling in hippocampal adult-born neurons. PMID:22586092

  1. Impact of floral feeding on adult Drosophila suzukii survival and nutrient status

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drosophila suzukii, spotted wing drosophila, is a serious pest of small fruits and cherries in many regions of the world. While host usage has been well studied at the ovipositional and larval feeding stages, little is known about the feeding ecology of adults. This study addressed the impact of fee...

  2. Sex-biased survival predicts adult sex ratio variation in wild birds

    PubMed Central

    Székely, Tamás; Liker, András; Freckleton, Robert P.; Fichtel, Claudia; Kappeler, Peter M.

    2014-01-01

    Adult sex ratio (ASR) is a central concept in population demography and breeding system evolution, and has implications for population viability and biodiversity conservation. ASR exhibits immense interspecific variation in wild populations, although the causes of this variation have remained elusive. Using phylogenetic analyses of 187 avian species from 59 families, we show that neither hatching sex ratios nor fledging sex ratios correlate with ASR. However, sex-biased adult mortality is a significant predictor of ASR, and this relationship is robust to 100 alternative phylogenetic hypotheses, and potential ecological and life-history confounds. A significant component of adult mortality bias is sexual selection acting on males, whereas increased reproductive output predicts higher mortality in females. These results provide the most comprehensive insights into ASR variation to date, and suggest that ASR is an outcome of selective processes operating differentially on adult males and females. Therefore, revealing the causes of ASR variation in wild populations is essential for understanding breeding systems and population dynamics. PMID:24966308

  3. Effects of body size and nutritional regimen on survival in adult Aedes albopictus (Diptera: Culicidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of adult body size and nutritional regimen on the mean time to death (LT) for the 50th (LT50) and 90th centiles (LT90) of large and small male and female Aedes albopictus (Skuse) was determined in the laboratory. The estimated LT50 and the LT90 for large/small females was significantly ...

  4. Effect of methoprene application, adult food and feeding duration on male melon fly starvation survival

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The application of methoprene and access to protein in adult diet has been shown to enhance mating success in male melon fly Bactrocera cucurbitae Coquillett (Diptera: Tephritidae), supporting their incorporation into operational area-wide programmes integrating the Sterile Insect Technique (SIT). T...

  5. Sex-biased survival predicts adult sex ratio variation in wild birds.

    PubMed

    Székely, Tamás; Liker, András; Freckleton, Robert P; Fichtel, Claudia; Kappeler, Peter M

    2014-08-01

    Adult sex ratio (ASR) is a central concept in population demography and breeding system evolution, and has implications for population viability and biodiversity conservation. ASR exhibits immense interspecific variation in wild populations, although the causes of this variation have remained elusive. Using phylogenetic analyses of 187 avian species from 59 families, we show that neither hatching sex ratios nor fledging sex ratios correlate with ASR. However, sex-biased adult mortality is a significant predictor of ASR, and this relationship is robust to 100 alternative phylogenetic hypotheses, and potential ecological and life-history confounds. A significant component of adult mortality bias is sexual selection acting on males, whereas increased reproductive output predicts higher mortality in females. These results provide the most comprehensive insights into ASR variation to date, and suggest that ASR is an outcome of selective processes operating differentially on adult males and females. Therefore, revealing the causes of ASR variation in wild populations is essential for understanding breeding systems and population dynamics. PMID:24966308

  6. Adding chemo after radiation treatment improves survival for adults with a type of brain tumor

    Cancer.gov

    Adults with low-grade gliomas, a form of brain tumor, who received chemotherapy following completion of radiation therapy lived longer than patients who received radiation therapy alone, according to long-term follow-up results from a NIH-supported random

  7. PM2.5 and survival among older adults: Effect modification by particulate composition

    PubMed Central

    Kioumourtzoglou, Marianthi-Anna; Austin, Elena; Koutrakis, Petros; Dominici, Francesca; Schwartz, Joel; Zanobetti, Antonella

    2015-01-01

    Background Fine particulate (PM2.5) air pollution has been consistently linked to survival, but reported effect estimates are geographically heterogeneous. Exposure to different types of particle mixtures may explain some of this variation. Methods We used k-means cluster analyses to identify cities with similar pollution profiles, (i.e. PM2.5 composition) across the US. We examined the impact of PM2.5 on survival, and its variation across clusters of cities with similar PM2.5 composition, among Medicare enrollees in 81 US cities (2000–2010). We used time-varying annual PM2.5 averages, measured at ambient central monitoring sites, as the exposure of interest. We ran by-city Cox models, adjusting for individual data on previous cardiopulmonary-related hospitalizations and stratifying by follow-up time, age, gender and race. This eliminates confounding by factors varying across cities and long-term trends, focusing on year-to-year variations of air pollution around its city-specific mean and trend. We then pooled the city-specific effects using a random effects meta-regression. In this second stage, we also assessed effect modification by cluster membership and estimated cluster-specific PM2.5 effects. Results We followed more than 19 million subjects and observed more than 6 million deaths. We found a harmful impact of annual PM2.5 concentrations on survival (HR = 1.11 [95% confidence interval = 1.01–1.23] per 10 µg/m3). This effect was modified by particulate composition, with higher effects observed in clusters containing high concentrations of nickel, vanadium and sulfate. For instance, our highest effect estimate was observed in cities with harbors in the Northwest, characterized by high nickel, vanadium and elemental carbon concentrations (1.9 [1.1–3.3]). We observed null or negative associations in clusters with high oceanic and crustal particles. Conclusions To our knowledge, this is the first study to examine the association between PM2.5 composition

  8. Exogenous Modulation of Retinoic Acid Signaling Affects Adult RGC Survival in the Frog Visual System after Optic Nerve Injury.

    PubMed

    Duprey-Díaz, Mildred V; Blagburn, Jonathan M; Blanco, Rosa E

    2016-01-01

    After lesions to the mammalian optic nerve, the great majority of retinal ganglion cells (RGCs) die before their axons have even had a chance to regenerate. Frog RGCs, on the other hand, suffer only an approximately 50% cell loss, and we have previously investigated the mechanisms by which the application of growth factors can increase their survival rate. Retinoic acid (RA) is a vitamin A-derived lipophilic molecule that plays major roles during development of the nervous system. The RA signaling pathway is also present in parts of the adult nervous system, and components of it are upregulated after injury in peripheral nerves but not in the CNS. Here we investigate whether RA signaling affects long-term RGC survival at 6 weeks after axotomy. Intraocular injection of all-trans retinoic acid (ATRA), the retinoic acid receptor (RAR) type-α agonist AM80, the RARβ agonist CD2314, or the RARγ agonist CD1530, returned axotomized RGC numbers to almost normal levels. On the other hand, inhibition of RA synthesis with disulfiram, or of RAR receptors with the pan-RAR antagonist Ro-41-5253, or the RARβ antagonist LE135E, greatly reduced the survival of the axotomized neurons. Axotomy elicited a strong activation of the MAPK, STAT3 and AKT pathways; this activation was prevented by disulfiram or by RAR antagonists. Finally, addition of exogenous ATRA stimulated the activation of the first two of these pathways. Future experiments will investigate whether these strong survival-promoting effects of RA are mediated via the upregulation of neurotrophins. PMID:27611191

  9. Effect of temperature on Osmia lignaria (Hymenoptera: Megachilidae) prepupa-adult development, survival, and emergence.

    PubMed

    Kemp, W P; Bosch, J

    2005-12-01

    The solitary bee Osmia lignaria Say continues to be developed as an orchard pollinator in the United States and southern Canada. Female bees are active during the early spring and construct nests consisting of a linear series of unlined cells delimited by mud partitions. Cells are provisioned with a pollen/nectar mass on which an egg is deposited, and nests are sealed with a mud plug. In 1997, we initiated two experiments on the development, mortality, and emergence of O. lignaria at selected laboratory temperature regimes and outdoors. In the first experiment (published previously), we compared temperature treatments for their adequacy in maintaining healthy O. lignaria populations. In a second experiment (reported here), we determined the relationship between rearing temperatures and prepupa-adult development rates as well as emergence time and longevity after wintering and incubation the following spring. We observed important differences in O. lignaria prepupa versus pupa responses to selected temperature treatments. The relationship between temperature and days to pupa was U-shaped, with additional time to transit the prepupa-pupa interval at temperatures above and below 26 degrees C. The negative relationship between temperature and the length of the pupa to adult interval contrasts with the U-shaped thermal response observed for prepupae. Thus, with each increase in thermal heat units over the range of temperature treatments tested, we observed an additional reduction in the pupa-adult interval. Individuals reared at constant 18 degrees C required 2.4 times as many days to transit the pupa-adult interval compared with those at constant 32 degrees C. Our results suggest that there is a need for the development of regionally adapted, latitude-specific breeding populations of this outstanding orchard crop pollinator. PMID:16539114

  10. Hydroxyurea-Increased Fetal Hemoglobin Is Associated with Less Organ Damage and Longer Survival in Adults with Sickle Cell Anemia

    PubMed Central

    Fitzhugh, Courtney D.; Hsieh, Matthew M.; Allen, Darlene; Coles, Wynona A.; Seamon, Cassie; Ring, Michael; Zhao, Xiongce; Minniti, Caterina P.; Rodgers, Griffin P.; Schechter, Alan N.; Tisdale, John F.; Taylor, James G.

    2015-01-01

    Background Adults with sickle cell anemia (HbSS) are inconsistently treated with hydroxyurea. Objectives We retrospectively evaluated the effects of elevating fetal hemoglobin with hydroxyurea on organ damage and survival in patients enrolled in our screening study between 2001 and 2010. Methods An electronic medical record facilitated development of a database for comparison of study parameters based on hydroxyurea exposure and dose. This study is registered with ClinicalTrials.gov, number NCT00011648. Results Three hundred eighty-three adults with homozygous sickle cell disease were analyzed with 59 deaths during study follow-up. Cox regression analysis revealed deceased subjects had more hepatic dysfunction (elevated alkaline phosphatase, Hazard Ratio = 1.005, 95% CI 1.003–1.006, p<0.0.0001), kidney dysfunction (elevated creatinine, Hazard Ratio = 1.13, 95% CI 1.00–1.27, p = 0.043), and cardiopulmonary dysfunction (elevated tricuspid jet velocity on echocardiogram, Hazard Ratio = 2.22, 1.23–4.02, p = 0.0082). Sixty-six percent of subjects were treated with hydroxyurea, although only 66% of those received a dose within the recommended therapeutic range. Hydroxyurea use was associated with improved survival (Hazard Ratio = 0.58, 95% CI 0.34–0.97, p = 0.040). This effect was most pronounced in those taking the recommended dose of 15–35 mg/kg/day (Hazard Ratio 0.36, 95% CI 0.17–0.73, p = 0.0050). Hydroxyurea use was not associated with changes in organ function over time. Further, subjects with higher fetal hemoglobin responses to hydroxyurea were more likely to survive (p = 0.0004). While alkaline phosphatase was lowest in patients with the best fetal hemoglobin response (95.4 versus 123.6, p = 0.0065 and 96.1 versus 113.6U/L, p = 0.041 at first and last visits, respectively), other markers of organ damage were not consistently improved over time in patients with the highest fetal hemoglobin levels. Conclusions Our data suggest that adults should be

  11. Relative influence of human harvest, carnivores, and weather on adult female elk survival across western North America

    USGS Publications Warehouse

    Brodie, Jedediah; Johnson, Heather; Mitchell, Michael; Zager, Peter; Proffitt, Kelly; Hebblewhite, Mark; Kauffman, Matthew; Johnson, Bruce; Bissonette, John; Bishop, Chad; Gude, Justin; Herbert, Jeff; Hersey, Kent; Hurley, Mark; Lukacs, Paul M.; McCorquodale, Scott; McIntire, Eliot; Nowak, Josh; Sawyer, Hall; Smith, Douglas; White, P.J.

    2013-01-01

    Well-informed management of harvested species requires understanding how changing ecological conditions affect demography and population dynamics, information that is lacking for many species. We have limited understanding of the relative influence of carnivores, harvest, weather and forage availability on elk Cervus elaphus demography, despite the ecological and economic importance of this species. We assessed adult female survival, a key vital rate for population dynamics, from 2746 radio-collared elk in 45 populations across western North America that experience wide variation in carnivore assemblage, harvest, weather and habitat conditions. Proportional hazard analysis revealed that 'baseline' (i.e. not related to human factors) mortality was higher with very high winter precipitation, particularly in populations sympatric with wolves Canis lupus. Mortality may increase via nutritional stress and heightened vulnerability to predation in snowy winters. Baseline mortality was unrelated to puma Puma concolor presence, forest cover or summer forage productivity. Cause-specific mortality analyses showed that wolves and all carnivore species combined had additive effects on baseline elk mortality, but only reduced survival by <2%. When human factors were included, ‘total’ adult mortality was solely related to harvest; the influence of native carnivores was compensatory. Annual total mortality rates were lowest in populations sympatric with both pumas and wolves because managers reduced female harvest in areas with abundant or diverse carnivores. Mortality from native carnivores peaked in late winter and early spring, while harvest-induced mortality peaked in autumn. The strong peak in harvest-induced mortality during the autumn hunting season decreased as the number of native carnivore species increased. Synthesis and applications. Elevated baseline adult female elk mortality from wolves in years with high winter precipitation could affect elk abundance as

  12. Clinical presentation, etiology, and survival in adult acute encephalitis syndrome in rural Central India

    PubMed Central

    Joshi, Rajnish; Mishra, Pradyumna Kumar; Joshi, Deepti; Santhosh, SR; Parida, M.M.; Desikan, Prabha; Gangane, Nitin; Kalantri, S.P.; Reingold, Arthur; Colford, John M.

    2013-01-01

    Background Acute encephalitis syndrome (AES) is a constellation of symptoms that includes fever and altered mental status. Most cases are attributed to viral encephalitis (VE), occurring either in outbreaks or sporadically. We conducted hospital-based surveillance for sporadic adult-AES in rural Central India in order to describe its incidence, spatial and temporal distribution, clinical profile, etiology and predictors of mortality. Methods All consecutive hospital admissions during the study period were screened to identify adult-AES cases and were followed until 30-days of hospitalization. We estimated incidence by administrative sub-division of residence and described the temporal distribution of cases. We performed viral diagnostic studies on cerebrospinal fluid (CSF) samples to determine the etiology of AES. The diagnostic tests included RT-PCR (for enteroviruses, HSV 1 and 2), conventional PCR (for flaviviruses), CSF IgM capture ELISA (for Japanese encephalitis virus, dengue, West Nile virus, Varicella zoster virus, measles, and mumps). We compared demographic and clinical variables across etiologic subtypes and estimated predictors of 30-day mortality. Results A total of 183 AES cases were identified between January and October 2007, representing 2.38% of all admissions. The incidence of adult AES in the administrative subdivisions closest to the hospital was 16 per 100,000. Of the 183 cases, a non-viral etiology was confirmed in 31 (16.9%) and the remaining 152 were considered as VE suspects. Of the VE suspects, we could confirm a viral etiology in 31 cases: 17 (11.2%) enterovirus; 8 (5.2%) flavivirus; 3 (1.9%) Varicella zoster; 1 (0.6%) herpesvirus; and 2 (1.3%) mixed etiology); the etiology remained unknown in remaining 121 (79.6%) cases. 53 (36%) of the AES patients died; the case fatality proportion was similar in patients with a confirmed and unknown viral etiology (45.1 and 33.6% respectively). A requirement for assisted ventilation significantly

  13. Self-perceptions of young adults who survived severe childhood burn injury.

    PubMed

    Russell, William; Robert, Rhonda S; Thomas, Christopher R; Holzer, Charles E; Blakeney, Patricia; Meyer, Walter J

    2013-01-01

    The transition of pediatric burn survivors into adulthood is accompanied by a reformulation of their self-concept. To anticipate the need for and guide development of appropriate psychosocial interventions, this study examines how young adults who were burned as children perceive themselves and how this perception might affect their self-esteem. Eighty-two young adult burn survivors (45 male, 37 female) were assessed using the Tennessee Self-Concept Scale, 2nd edition (TSCS2) to determine how the participants perceive themselves and their interaction with society. To gain insight into the possible effects of these self-concept scores, relationships were analyzed between self-concept, a behavioral assessment (Young Adult Self-Report [YASR]), and a psychiatric symptom assessment (Structured Clinical Interview for DSM-IV Axis I Disorders [SCID I]). This group of burn survivors scored significantly lower in self-concepts, reflected in TSCS2 subscale scores of physical function, appearance, and sexuality, moral conduct, personal values, academics and work, and identity, than did the reference population. Pearson correlation coefficients showed that as moral, personal, family, and social aspects of self-concept decreased, clinical problems endorsed on the YASR subscales increased, including anxiety, somatic, attention, intrusive, and aggressive. Persons with lower self-concept scores on the TSCS2 personal, family, and social scales were more withdrawn on the YASR. Similarly, those with lower TSCS2 scores on the personal and family scales endorsed significantly more thought problems on the YASR. TSCS2 total self-concept, personal, and all of the supplementary scale scores were significantly lower for the group with an affective disorder. Those whose SCID I scores were consistent with a current anxiety disorder had significantly lower scores for the TSCS2 total self-concept and personal. Lower self-concept was associated with endorsement of SCID symptoms. In summary, the

  14. Self Perceptions of Young Adults who Survived Severe Childhood Burn Injury

    PubMed Central

    Russell, W; Robert, RS; Thomas, CR; Holzer, CE; Blakeney, P; Meyer, WJ

    2012-01-01

    Objective The transition of pediatric burn survivors into adulthood is accompanied by a reformulation of their self concept. In order to anticipate the need for and guide development of appropriate psychosocial interventions, this study examines how young adults who were burned as children perceive themselves and how this perception might affect their self-esteem. Method 82 young adult burn survivors (45 males, 37 females) were assessed using the Tennessee Self-Concept, 2nd Edition (TSCS2) to determine how the participants perceive themselves and their interaction with society. To gain insight into the possible effects of these self-concept scores, relationships were analyzed between self-concept, a behavioral assessment (Young Adult Self-Report, YASR) and a psychiatric symptom assessment (Structured Clinical Interview for DSM-IV Axis I Disorders, SCID I). Results This group of burn survivors scored significantly lower in self-concepts, reflected in TSCS2 sub-scale scores of Physical function, appearance, and sexuality, Moral conduct, Personal values, Academics and work, and Identity than did the reference population. Pearson correlation coefficients showed that as Moral, Personal, Family and Social aspects of self concept decreased, clinical problems endorsed on the YASR sub-scales increased, including Anxiety Somatic, Attention, Intrusive and Aggressive. Persons with lower self-concept scores on the TSCS2 Personal, Family, and Social Scales, were more withdrawn on the YASR. Similarly those with lower TSCS2 scores on the Personal and Family Scales endorsed significantly more Thought Problems on the YASR. Affective distress on the SCID I was associated with significantly lower self concept. TSCS2 Total Self Concept, Personal, and all of the Supplementary Scale scores were significantly lower for the group with an affective disorder. Those whose SCID I scores were consistent with a current anxiety disorder had significantly lower scores for the TSCS2 Total Self

  15. Chronic cocaine exposure impairs progenitor proliferation but spares survival and maturation of neural precursors in adult rat dentate gyrus.

    PubMed

    Domínguez-Escribà, L; Hernández-Rabaza, V; Soriano-Navarro, M; Barcia, J A; Romero, F J; García-Verdugo, J M; Canales, J J

    2006-07-01

    Recent observations indicate that drugs of abuse, including alcohol and opiates, impair adult neurogenesis in the hippocampus. We have studied in rats the impact of cocaine treatment (20 mg/kg, daily, i.p.) on cell proliferation, survival and maturation following short-term (8-day) and long-term (24-day) exposure. Using 5'-bromo-2-deoxyuridine (BrdU) and Ki-67 as mitotic markers at the end of the drug treatments, we found that both short- and long-term cocaine exposures significantly reduced cell proliferation in the dentate gyrus (DG) of the hippocampus. By labelling mitotic cells with BrdU pulses before or during the early stages of the drug treatment, we determined that long-term cocaine exposure did not affect the survival of newly generated cells. In register with this finding, cocaine chronic exposure did not increase the number of apoptotic cells labelled by TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling). Using doublecortin (DCX) immunocytochemistry and electron microscopy, we next examined the effects of cocaine exposure on the maturation of the neural precursors and on synaptic output to CA3. DCX immunocytochemistry showed that immature hippocampal cells of rats exposed to cocaine displayed normal arborization patterns and similar degrees of colocalization with BrdU at two different developmental stages. Moreover, cocaine did not produce significant morphological alterations of the mossy fibre projection system to stratum lucidum in the CA3 area of the hippocampus. The results presented demonstrate that chronic cocaine exposure impairs proliferation dynamics in the DG without significantly altering either the survival and growth of immature cells or the structural features of terminal projections to CA3. PMID:16903860

  16. Retinal Microvasculature Is Associated With Long-Term Survival in the General Adult Dutch Population.

    PubMed

    Mutlu, Unal; Ikram, M Kamran; Wolters, Frank J; Hofman, Albert; Klaver, Caroline C W; Ikram, M Arfan

    2016-02-01

    Retinal vascular diameters are associated with (sub)clinical cardiovascular disease and short-term cardiovascular mortality, but their association with long-term mortality is uncertain. We studied the association of retinal vascular diameters with cause-specific mortality in the general adult Dutch population during 25 years of follow-up. From 1990 to 1993, arteriolar and venular diameters were measured semiautomatically on digitized images in 5674 persons (mean age 68.0 years, 59% women) from the population-based Rotterdam study. Follow-up for mortality was complete till March 2015. Associations between vascular diameters and mortality were examined using Cox proportional hazards models, adjusting for age, sex, cardiovascular risk factors, and the fellow vessel diameter. During 85 770 person-years (mean±SD: 15.1±6.67), 3794 (66.8%) persons died, of whom 1034 due to cardiovascular causes. We found that narrower arterioles and wider venules were associated with higher risk of mortality (adjusted hazard ratio [95% confidence interval] per SD decrease 1.04 [1.00-1.08] and increase 1.07 [1.03-1.12], respectively). For arterioles, these associations were strongest for cardiovascular mortality, whereas venules showed consistent associations for cardiovascular and noncardiovascular mortality. Importantly, these associations remained unchanged after excluding the first 10 years of follow-up as immortal person-time. We found evidence for effect modification with stronger associations in persons <70 years (venules only) and smokers (P value for interaction<0.01). We replicated our findings in another independent cohort from the Rotterdam Study of 3106 persons with 19 880 person-years of follow-up and 144 deaths (hazard ratio for venules 1.22 [1.00-1.49]). Markers of retinal microvasculature are associated with long-term mortality in the general adult Dutch population. PMID:26628677

  17. Quality of life and perceived health status in surviving adults with univentricular heart

    PubMed Central

    Saliba, Z; Butera, G; Bonnet, D; Bonhoeffer, P; Villain, E; Kachaner, J; Sidi, D; Iserin, L

    2001-01-01

    OBJECTIVE—To evaluate the quality of life in patients with univentricular heart and to determine the impact of sociodemographic and clinical characteristics.
DESIGN AND SETTING—Retrospective, cross sectional study conducted in a regional paediatric cardiology centre.
PATIENTS—The health records of 89 survivors with univentricular heart (median age 21 years; range 17-49 years) were reviewed. Sixty seven answered the Duke questionnaire. Sociodemographic and clinical variables were similar in the responders and non-responders. The impact of sociodemographic and clinical variables on individual Duke's measures was assessed.
RESULTS—The Duke scores of adults with univentricular heart were similar to the normal population. Cyanosis predicted a worse score for physical (p = 0.05) and perceived health measures (p = 0.02). A higher educational level predicted a better score for physical (p = 0.004), mental (p = 0.01), and general health measures (p = 0.02). Orthopaedic problems worsened the social score (p = 0.05). Psychosocial problems worsened the pain score (p = 0.04). In comparison with the other anatomical types, mitral atresia worsened the perceived health score (p = 0.02). Patients younger than 23 years scored better for almost all health and dysfunction measures.
CONCLUSIONS—Despite repeated interventions and other disease related everyday stresses, a selected group of adults with univentricular heart had a satisfying quality of life.


Keywords: congenital heart defect; quality of life; psychosocial problems; univentricular heart PMID:11410565

  18. A Single Hot Event Stimulates Adult Performance but Reduces Egg Survival in the Oriental Fruit Moth, Grapholitha molesta

    PubMed Central

    Ma, Gang; Hoffmann, Ary A.; Ma, Chun-Sen

    2014-01-01

    Climate warming is expected to increase the exposure of insects to hot events (involving a few hours at extreme high temperatures). These events are unlikely to cause widespread mortality but may modify population dynamics via impacting life history traits such as adult fecundity and egg hatching. These effects and their potential impact on population predictions are still largely unknown. In this study, we simulated a single hot event (maximum of 38°C lasting for 4 h) of a magnitude increasingly found under field conditions and examined its effect in the oriental fruit moth, Grapholitha molesta. This hot event had no impact on the survival of G. molesta adults, copulation periods or male longevity. However, the event increased female lifespan and the length of the oviposition period, leading to a potential increase in lifetime fecundity and suggesting hormesis. In contrast, exposure of males to this event markedly reduced the net reproductive value. Male heat treatment delayed the onset of oviposition in the females they mated with, as well as causing a decrease in the duration of oviposition period and lifetime fecundity. Both male and female stress also reduced egg hatch. Our findings of hormetic effects on female performance but concurrent detrimental effects on egg hatch suggest that hot events have unpredictable consequences on the population dynamics of this pest species with implications for likely effects associated with climate warming. PMID:25551751

  19. HIGH PROBABILITY OF LONG-TERM SURVIVAL IN 2-YEAR SURVIVORS OF AUTOLOGOUS HEMATOPOIETIC CELL TRANSPLANTATION FOR ACUTE MYELOID LEUKEMIA IN FIRST OR SECOND COMPLETE REMISSION

    PubMed Central

    Majhail, Navneet S.; Bajorunaite, Ruta; Lazarus, Hillard M.; Wang, Zhiwei; Klein, John P.; Zhang, Mei-Jie; Rizzo, J. Douglas

    2010-01-01

    We describe long-term outcomes of autologous hematopoietic-cell transplantation (HCT) for 315 acute myeloid leukemia (AML) patients in first or second complete remission (CR). All patients were in continuous CR for ≥2-years post-HCT. Patients were predominantly transplanted in CR1 (78%) and had good or intermediate cytogenetic risk disease (74%). Median followup of survivors was 106 (range, 24-192) months. Overall survival at 10-years post-HCT was 94% (95% confidence intervals, 89-97%) and 80% (67-91%) for patients receiving HCT in CR1 and CR2, respectively. The cumulative incidence of relapse at 10-years post-HCT was 6% (3-10%) and 10% (3-20%) and that of non-relapse mortality was 5% (2-9%) and 11% (4-21%), respectively. On multivariate analysis, HCT in CR2 (vs. CR1), older age at transplantation and poor cytogenetic risk disease were independent predictors of late mortality and adverse disease-free survival. The use of growth factors to promote engraftment following HCT was the only risk factor for relapse. Relative-mortality of these 2-year survivors was comparable to that of age-, race- and gender-matched normal population. Patients who receive an autologous HCT for AML in CR1 or CR2 and remain in remission for ≥2-years have very favorable long-term survival. Their mortality rates are similar to that of the general population. PMID:20479710

  20. Spawning areas of eastern Baltic cod revisited: Using hydrodynamic modelling to reveal spawning habitat suitability, egg survival probability, and connectivity patterns

    NASA Astrophysics Data System (ADS)

    Hinrichsen, H.-H.; Lehmann, A.; Petereit, C.; Nissling, A.; Ustups, D.; Bergström, U.; Hüssy, K.

    2016-04-01

    In the highly variable environment of the Baltic Sea two genetically distinct cod stocks exist, one west of the island of Bornholm, which is referred to as the western stock, and one to the east of Bornholm, the eastern stock. A hydrodynamic model combined with a Lagrangian particle tracking technique was utilised to provide spatially and temporally resolved long-term information on environmentally-related (i) spawning habitat size, (ii) egg/yolk-sac larval survival, (iii) separation of causes of mortality, and (iv) connectivity between spawning areas of eastern Baltic cod. Simulations were performed to quantify processes generating heterogeneity in spatial distribution of cod eggs and yolk sac larvae up to the first-feeding stage. The spatial extent of cod eggs represented as virtual drifters is primarily determined by oxygen and salinity conditions at spawning, which define the habitat requirement to which cod's physiology is suited for egg development. The highest habitat suitability occurred in the Bornholm Basin, followed by the Gdansk Deep, while relatively low habitat suitability was obtained for the Arkona and the Gotland Basin. During drift egg and yolk sac larval survival is to a large extent affected by sedimentation. Eggs initially released in the western spawning grounds (Arkona and Bornholm Basin) were more affected by sedimentation than those released in the eastern spawning grounds (Gdansk Deep and Gotland Basin). Highest relative survival of eastern Baltic cod eggs occurred in the Bornholm Basin, with a pronounced decrease towards the Gdansk Deep and the Gotland Basin. Relatively low survival rates in the Gdansk Deep and in the Gotland Basin were attributable to oxygen-dependent mortality. Low oxygen content had almost no impact on survival in the Arkona Basin. For all spawning areas temperature dependent mortality was only evident after severe winters. Egg buoyancy in relation to topographic features like bottom sills and strong bottom slopes

  1. Social Cohesion and Mortality: A Survival Analysis of Older Adults in Japan

    PubMed Central

    Yorifuji, Takashi; Takao, Soshi; Doi, Hiroyuki; Kawachi, Ichiro

    2013-01-01

    Objectives. We examined the association between social cohesion and mortality in a sample of older adults in Japan. Methods. Data were derived from a cohort study of elderly individuals (65–84 years) in Shizuoka Prefecture; 14 001 participants were enrolled at baseline (1999) and followed up in 2002, 2006, and 2009. Among the 11 092 participants for whom we had complete data, 1427 had died during follow-up. We examined the association between social cohesion (assessed at both the community and individual levels) and subsequent mortality after control for baseline and time-varying covariates. We used clustered proportional hazard regression models to estimate hazard ratios (HRs) and confidence intervals (CIs). Results. After control for individual characteristics, individual perceptions of community cohesion were associated with a reduced risk of all-cause mortality (HR = 0.78; 95% CI = 0.73, 0.84) as well as mortality from cardiovascular disease (HR = 0.75; 95% CI = 0.67, 0.84), pulmonary disease (HR = 0.66; 95% CI = 0.58, 0.75), and all other causes (HR = 0.76; 95% CI = 0.66, 0.89). However, no statistically significant relationship was found between community cohesion and mortality risk. Conclusions. Among the elderly in Japan, more positive individual perceptions of community cohesion are associated with reduced risks of all-cause and cause-specific mortality. PMID:24134379

  2. Hate crimes and stigma-related experiences among sexual minority adults in the United States: prevalence estimates from a national probability sample.

    PubMed

    Herek, Gregory M

    2009-01-01

    Using survey responses collected via the Internet from a U.S. national probability sample of gay, lesbian, and bisexual adults (N = 662), this article reports prevalence estimates of criminal victimization and related experiences based on the target's sexual orientation. Approximately 20% of respondents reported having experienced a person or property crime based on their sexual orientation; about half had experienced verbal harassment, and more than 1 in 10 reported having experienced employment or housing discrimination. Gay men were significantly more likely than lesbians or bisexuals to experience violence and property crimes. Employment and housing discrimination were significantly more likely among gay men and lesbians than among bisexual men and women. Implications for future research and policy are discussed. PMID:18391058

  3. Increasing intensity of therapies assigned at diagnosis does not improve survival of adults with acute myeloid leukemia.

    PubMed

    Krug, U; Berdel, W E; Gale, R P; Haferlach, C; Schnittger, S; Müller-Tidow, C; Braess, J; Spiekermann, K; Staib, P; Beelen, D; Serve, H; Schliemann, C; Stelljes, M; Balleisen, L; Maschmeyer, G; Grüneisen, A; Eimermacher, H; Giagounidis, A; Rasche, H; Hehlmann, R; Lengfelder, E; Thiel, E; Reichle, A; Aul, C; Ludwig, W-D; Kern, W; Haferlach, T; Köpcke, W; Görlich, D; Sauerland, M C; Heinecke, A; Wörmann, B J; Hiddemann, W; Büchner, T

    2016-06-01

    We randomized 3375 adults with newly diagnosed acute myeloid leukemia (AML) or high-risk myelodysplastic syndrome to test whether increasingly intensive chemotherapies assigned at study-entry and analyzed on an intent-to-treat basis improved outcomes. In total, 1529 subjects <60 years were randomized to receive: (1) a first course of induction therapy with high-dose cytarabine and mitoxantrone (HAM) or with standard-dose cytarabine, daunorubicin and 6-thioguanine (TAD) followed by a second course of HAM; (2) granulocyte-colony stimulating factor (G-CSF) or no G-CSF before induction and consolidation courses; and (3) high-dose therapy and an autotransplant or maintenance chemotherapy. In total, 1846 subjects ⩾60 years were randomized to receive: (1) a first induction course of HAM or TAD and second induction course of HAM (if they had bone marrow blasts ⩾5% after the first course); and (2) G-CSF or no G-CSF as above. Median follow-up was 7.4 years (range, 1 day to 14.7 years). Five-year event-free survivals (EFSs) for subjects receiving a first induction course of HAM vs TAD were 17% (95% confidence interval, 15, 18%) vs 16% (95% confidence interval 14, 18%; P=0.719). Five-year EFSs for subjects randomized to receive or not receive G-CSF were 19% (95% confidence interval 16, 21%) vs 16% (95% confidence interval 14, 19%; P=0.266). Five-year relapse-free survivals (RFSs) for subjects <60 years receiving an autotransplant vs maintenance therapy were 43% (95% confidence interval 40, 47%) vs 40 (95% confidence interval 35, 44%; P=0.535). Many subjects never achieved pre-specified landmarks and consequently did not receive their assigned therapies. These data indicate the limited impact of more intensive therapies on outcomes of adults with AML. Moreover, none of the more intensive therapies we tested improved 5-year EFS, RFS or any other outcomes. PMID:26859081

  4. Characteristics of Adult T-Cell Leukemia/Lymphoma Patients with Long Survival: Prognostic Significance of Skin Lesions and Possible Beneficial Role of Valproic Acid.

    PubMed

    Yves, Plumelle; Stephane, Michel; Rishika, Banydeen; Christine, Delaunay; Gérard, Panelatti

    2015-01-01

    We describe the clinical and biological features of ten patients with a survival superior to ten years (long survival), out of 175 patients diagnosed with Adult T-cell Leukemia/Lymphoma (ATL) in Martinique (1983-2013). There were 5 lymphoma and 5 chronic subtypes. Five of them (3 chronic, 2 lymphoma) had been treated with valproic acid (VA) for neurological disorders developed before or after ATL diagnosis, suggesting a beneficial role for VA as a histone deacetylase inhibitor (HDI) in ATL treatment. Total duration of uninterrupted VA treatment ranged from 8 to 37 years. Overall, the 175 incident ATL cases presented with a median survival of 5.43 months. The five VA-treated (VA(+)) patients presented with longer survival compared to VA treatment-free patients (VA(-)). For chronic subtypes, survival periods were of 213 months for 3 VA(+) patients and of 33 months for 11 VA(-) patients (p = 0.023). For lymphoma subtypes, survival periods were of 144 months for 2 VA(+) patients versus 6 months for 49 VA(-) patients (p = 0.0046). ATL cases with skin lesions, particularly lymphoma subtypes, had a longer survival (13.96 months) compared to those without skin lesions (6.06 months, p = 0.002). Eight out of the 10 patients presenting with long survival had skin lesions. PMID:26199759

  5. Characteristics of Adult T-Cell Leukemia/Lymphoma Patients with Long Survival: Prognostic Significance of Skin Lesions and Possible Beneficial Role of Valproic Acid

    PubMed Central

    Yves, Plumelle; Stephane, Michel; Rishika, Banydeen; Christine, Delaunay; Gérard, Panelatti

    2015-01-01

    We describe the clinical and biological features of ten patients with a survival superior to ten years (long survival), out of 175 patients diagnosed with Adult T-cell Leukemia/Lymphoma (ATL) in Martinique (1983–2013). There were 5 lymphoma and 5 chronic subtypes. Five of them (3 chronic, 2 lymphoma) had been treated with valproic acid (VA) for neurological disorders developed before or after ATL diagnosis, suggesting a beneficial role for VA as a histone deacetylase inhibitor (HDI) in ATL treatment. Total duration of uninterrupted VA treatment ranged from 8 to 37 years. Overall, the 175 incident ATL cases presented with a median survival of 5.43 months. The five VA-treated (VA+) patients presented with longer survival compared to VA treatment-free patients (VA−). For chronic subtypes, survival periods were of 213 months for 3 VA+ patients and of 33 months for 11 VA− patients (p = 0.023). For lymphoma subtypes, survival periods were of 144 months for 2 VA+ patients versus 6 months for 49 VA− patients (p = 0.0046). ATL cases with skin lesions, particularly lymphoma subtypes, had a longer survival (13.96 months) compared to those without skin lesions (6.06 months, p = 0.002). Eight out of the 10 patients presenting with long survival had skin lesions. PMID:26199759

  6. Improved graft-versus-host disease-free, relapse-free survival associated with bone marrow as the stem cell source in adults

    PubMed Central

    Mehta, Rohtesh S.; de Latour, Regis Peffault; DeFor, Todd E; Robin, Marie; Lazaryan, Aleksandr; Xhaard, Aliénor; Bejanyan, Nelli; de Fontbrune, Flore Sicre; Arora, Mukta; Brunstein, Claudio G.; Blazar, Bruce R.; Weisdorf, Daniel J.; MacMillan, Margaret L.; Socie, Gerard; Holtan, Shernan G.

    2016-01-01

    We previously reported that bone marrow grafts from matched sibling donors resulted in best graft-versus-host disease-free, relapse-free survival at 1-year post allogeneic hematopoietic cell transplantation. However, pediatric patients comprised the majority of bone marrow graft recipients in that study. To better define this outcome in adults and pediatric patients at 1- and 2-years post- allogeneic hematopoietic cell transplantation, we pooled data from the University of Minnesota and the Hôpital Saint-Louis in Paris, France (n=1901). Graft-versus-host disease-free, relapse-free survival was defined as the absence of grade III–IV acute graft-versus-host disease, chronic graft-versus-host disease (requiring systemic therapy or extensive stage), relapse and death. In adults, bone marrow from matched sibling donors (n=123) had best graft-versus-host disease-free, relapse-free survival at 1- and 2-years, compared with peripheral blood stem cell from matched sibling donors (n=540) or other graft/donor types. In multivariate analysis, peripheral blood stem cells from matched sibling donors resulted in a 50% increased risk of events contributing to graft-versus-host disease-free, relapse-free survival at 1- and 2-years than bone marrow from matched sibling donors. With limited numbers of peripheral blood stem cell grafts in pediatric patients (n=12), graft-versus-host disease-free, relapse-free survival did not differ between bone marrow and peripheral blood stem cell graft from any donor. While not all patients have a matched sibling donor, graft-versus-host disease-free, relapse-free survival may be improved by the preferential use of bone marrow for adults with malignant diseases. Alternatively, novel graft-versus-host disease prophylaxis regimens are needed to substantially impact graft-versus-host disease-free, relapse-free survival with the use of peripheral blood stem cell. PMID:27036159

  7. Effects of low level laser treatment on the survival of axotomized retinal ganglion cells in adult Hamsters.

    PubMed

    So, Kwok-Fai; Leung, Mason Chin Pang; Cui, Qi

    2014-11-01

    Injury to axons close to the neuronal bodies in the mammalian central nervous system causes a large proportion of parenting neurons to degenerate. It is known that optic nerve transection close to the eye in rodents leads to a loss of about half of retinal ganglion cells in 1 week and about 90% in 2 weeks. Using low level laser treatment in the present study, we demonstrated that treatment with helium-neon (660 nm) laser with 15 mW power could delay retinal ganglion cell death after optic nerve axotomy in adult hamsters. The effect was most apparent in the first week with a short period of treatment time (5 minutes) in which 65-66% of retinal ganglion cells survived the optic nerve axotomy whereas 45-47% of retinal ganglion cells did so in optic nerve axotomy controls. We also found that single dose and early commencement of laser irradiation were important in protecting retinal ganglion cells following optic nerve axotomy. These findings thus convincingly show that appropriate laser treatment may be neuroprotective to retinal ganglion cells. PMID:25558230

  8. Estimation of Aedes aegypti (Diptera: Culicidae) population size and adult male survival in an urban area in Panama

    PubMed Central

    Neira, Marco; Lacroix, Renaud; Cáceres, Lorenzo; Kaiser, Paul E; Young, Josue; Pineda, Lleysa; Black, Isaac; Sosa, Nestor; Nimmo, Derric; Alphey, Luke; McKemey, Andrew

    2014-01-01

    Traditional mosquito control strategies rely heavily on the use of chemical insecticides. However, concerns about the efficiency of traditional control methods, environmental impact and emerging pesticide resistance have highlighted the necessity for developing innovative tools for mosquito control. Some novel strategies, including release of insects carrying a dominant lethal gene (RIDL®), rely on the sustained release of modified male mosquitoes and therefore benefit from a thorough understanding of the biology of the male of the species. In this report we present the results of a mark-release-recapture study aimed at: (i) establishing the survival in the field of laboratory-reared, wild-type male Aedes aegypti and (b) estimating the size of the local adult Ae. aegypti population. The study took place in Panama, a country where recent increases in the incidence and severity of dengue cases have prompted health authorities to evaluate alternative strategies for vector control. Results suggest a life expectancy of 2.3 days for released male mosquitoes (confidence interval: 1.78-2.86). Overall, the male mosquito population was estimated at 58 males/ha (range 12-81 males/ha), which can be extrapolated to an average of 0.64 pupae/person for the study area. The practical implications of these results are discussed. PMID:25410991

  9. Estimation of Aedes aegypti (Diptera: Culicidae) population size and adult male survival in an urban area in Panama.

    PubMed

    Neira, Marco; Lacroix, Renaud; Cáceres, Lorenzo; Kaiser, Paul E; Young, Josue; Pineda, Lleysa; Black, Isaac; Sosa, Nestor; Nimmo, Derric; Alphey, Luke; McKemey, Andrew

    2014-11-01

    Traditional mosquito control strategies rely heavily on the use of chemical insecticides. However, concerns about the efficiency of traditional control methods, environmental impact and emerging pesticide resistance have highlighted the necessity for developing innovative tools for mosquito control. Some novel strategies, including release of insects carrying a dominant lethal gene (RIDL®), rely on the sustained release of modified male mosquitoes and therefore benefit from a thorough understanding of the biology of the male of the species. In this report we present the results of a mark-release-recapture study aimed at: (i) establishing the survival in the field of laboratory-reared, wild-type male Aedes aegypti and (b) estimating the size of the local adult Ae. aegypti population. The study took place in Panama, a country where recent increases in the incidence and severity of dengue cases have prompted health authorities to evaluate alternative strategies for vector control. Results suggest a life expectancy of 2.3 days for released male mosquitoes (confidence interval: 1.78-2.86). Overall, the male mosquito population was estimated at 58 males/ha (range 12-81 males/ha), which can be extrapolated to an average of 0.64 pupae/person for the study area. The practical implications of these results are discussed. PMID:25410991

  10. Estimation of Aedes aegypti (Diptera: Culicidae) population size and adult male survival in an urban area in Panama.

    PubMed

    Neira, Marco; Lacroix, Renaud; Cáceres, Lorenzo; Kaiser, Paul E; Young, Josue; Pineda, Lleysa; Black, Isaac; Sosa, Nestor; Nimmo, Derric; Alphey, Luke; McKemey, Andrew

    2014-08-22

    Traditional mosquito control strategies rely heavily on the use of chemical insecticides. However, concerns about the efficiency of traditional control methods, environmental impact and emerging pesticide resistance have highlighted the necessity for developing innovative tools for mosquito control. Some novel strategies, including release of insects carrying a dominant lethal gene (RIDL®), rely on the sustained release of modified male mosquitoes and therefore benefit from a thorough understanding of the biology of the male of the species. In this report we present the results of a mark-release-recapture study aimed at: (i) establishing the survival in the field of laboratory-reared, wild-type male Aedes aegypti and (b) estimating the size of the local adult Ae. aegypti population. The study took place in Panama, a country where recent increases in the incidence and severity of dengue cases have prompted health authorities to evaluate alternative strategies for vector control. Results suggest a life expectancy of 2.3 days for released male mosquitoes (confidence interval: 1.78-2.86). Overall, the male mosquito population was estimated at 58 males/ha (range 12-81 males/ha), which can be extrapolated to an average of 0.64 pupae/person for the study area. The practical implications of these results are discussed. PMID:25165979

  11. Effects of low level laser treatment on the survival of axotomized retinal ganglion cells in adult Hamsters

    PubMed Central

    So, Kwok-Fai; Leung, Mason Chin Pang; Cui, Qi

    2014-01-01

    Injury to axons close to the neuronal bodies in the mammalian central nervous system causes a large proportion of parenting neurons to degenerate. It is known that optic nerve transection close to the eye in rodents leads to a loss of about half of retinal ganglion cells in 1 week and about 90% in 2 weeks. Using low level laser treatment in the present study, we demonstrated that treatment with helium-neon (660 nm) laser with 15 mW power could delay retinal ganglion cell death after optic nerve axotomy in adult hamsters. The effect was most apparent in the first week with a short period of treatment time (5 minutes) in which 65–66% of retinal ganglion cells survived the optic nerve axotomy whereas 45–47% of retinal ganglion cells did so in optic nerve axotomy controls. We also found that single dose and early commencement of laser irradiation were important in protecting retinal ganglion cells following optic nerve axotomy. These findings thus convincingly show that appropriate laser treatment may be neuroprotective to retinal ganglion cells. PMID:25558230

  12. Projecting demographic responses to climate change: adult and juvenile survival respond differently to direct and indirect effects of weather in a passerine population

    USGS Publications Warehouse

    Dybala, Kristen E.; Eadie, John M.; Gardali, Thomas; Seavy, Nathaniel E.; Herzog, Mark P.

    2013-01-01

    Few studies have quantitatively projected changes in demography in response to climate change, yet doing so can provide important insights into the processes that may lead to population declines and changes in species distributions. Using a long-term mark-recapture data set, we examined the influence of multiple direct and indirect effects of weather on adult and juvenile survival for a population of Song Sparrows (Melospiza melodia) in California. We found evidence for a positive, direct effect of winter temperature on adult survival, and a positive, indirect effect of prior rainy season precipitation on juvenile survival, which was consistent with an effect of precipitation on food availability during the breeding season. We used these relationships, and climate projections of significantly warmer and slightly drier winter weather by the year 2100, to project a significant increase in mean adult survival (12-17%) and a slight decrease in mean juvenile survival (4-6%) under the B1 and A2 climate change scenarios. Together with results from previous studies on seasonal fecundity and postfledging survival in this population, we integrated these results in a population model and projected increases in the population growth rate under both climate change scenarios. Our results underscore the importance of considering multiple, direct, and indirect effects of weather throughout the annual cycle, as well as differences in the responses of each life stage to climate change. Projecting demographic responses to climate change can identify not only how populations will be affected by climate change but also indicate the demographic process(es) and specific mechanisms that may be responsible. This information can, in turn, inform climate change adaptation plans, help prioritize future research, and identify where limited conservation resources will be most effectively and efficiently spent.

  13. Improving the Quality of Adult Mortality Data Collected in Demographic Surveys: Validation Study of a New Siblings' Survival Questionnaire in Niakhar, Senegal

    PubMed Central

    Helleringer, Stéphane; Pison, Gilles; Masquelier, Bruno; Kanté, Almamy Malick; Douillot, Laetitia; Duthé, Géraldine; Sokhna, Cheikh; Delaunay, Valérie

    2014-01-01

    Background In countries with limited vital registration, adult mortality is frequently estimated using siblings' survival histories (SSHs) collected during Demographic and Health Surveys (DHS). These data are affected by reporting errors. We developed a new SSH questionnaire, the siblings' survival calendar (SSC). It incorporates supplementary interviewing techniques to limit omissions of siblings and uses an event history calendar to improve reports of dates and ages. We hypothesized that the SSC would improve the quality of adult mortality data. Methods and Findings We conducted a retrospective validation study among the population of the Niakhar Health and Demographic Surveillance System in Senegal. We randomly assigned men and women aged 15–59 y to an interview with either the DHS questionnaire or the SSC. We compared SSHs collected in each group to prospective data on adult mortality collected in Niakhar. The SSC reduced respondents' tendency to round reports of dates and ages to the nearest multiple of five or ten (“heaping”). The SSC also had higher sensitivity in recording adult female deaths: among respondents whose sister(s) had died at an adult age in the past 15 y, 89.6% reported an adult female death during SSC interviews versus 75.6% in DHS interviews (p = 0.027). The specificity of the SSC was similar to that of the DHS questionnaire, i.e., it did not increase the number of false reports of deaths. However, the SSC did not improve the reporting of adult deaths among the brothers of respondents. Study limitations include sample selectivity, limited external validity, and multiple testing. Conclusions The SSC has the potential to collect more accurate SSHs than the questionnaire used in DHS. Further research is needed to assess the effects of the SSC on estimates of adult mortality rates. Additional validation studies should be conducted in different social and epidemiological settings. Trial Registration Controlled-Trials.com ISRCTN06849961

  14. Survival and determinants of mortality in adult HIV/Aids patients initiating antiretroviral therapy in Somali Region, Eastern Ethiopia

    PubMed Central

    Damtew, Bereket; Mengistie, Bezatu; Alemayehu, Tadesse

    2015-01-01

    Introduction Studies have shown high initial mortality in Antiretroviral Therapy (ART) programs from resource-limited settings. However, there is dearth of evidence on treatment outcomes and associated determinant factors in public hospitals. Therefore, the objective of this study is to assess survival and identify predictors of death in adult HIV-infected patients initiating ART at a public hospital in Eastern Ethiopia. Methods A retrospective cohort study was conducted by reviewing baseline and follow-up records of patients who started ART between December 1, 2007 and December 31, 2011 at Kharamara hospital. Time to death was the main outcome measure. Kaplan-Meier models were used to estimate mortality and Cox proportional hazards models to identify predictors of mortality. Results A total of 784 patients (58.4% females) were followed for a median of 60 months. There were 87 (11.1%) deaths yielding an overall mortality rate of 5.15/100 PYO (95% CI: 4.73-6.37). The estimated mortality was 8.4%, 9.8%, 11.3%, 12.7% and 14.1% at 6, 12, 24, 36 and 48 months respectively. The independent predictors of death were single marital status (AHR: 2.31; 95%CI: 1.18-4.50), a bedridden functional status (AHR: 5.91; 95%CI: 2.87-12.16), advanced WHO stage (AHR: 7.36; 95%CI: 3.17-17.12), BMI < 18.5 Kg/m2 (AHR: 2.20; 95%CI: 1.18-4.09), CD4 count < 50 cells/µL (AHR: 2.70; 95%CI: 1.26-5.80), severe anemia (AHR: 4.57; 95%CI: 2.30-9.10), and TB co-infection (AHR: 2.30; 95%CI: 1.28-4.11). Conclusion Improved survival was observed in patients taking ART in Somali region of Ethiopia. The risk for death was higher in patients with advanced WHO stage, low CD4 count, low Hgb, low BMI, and concomitant TB infection. Intensive case management is recommended for patients with the prognostic factors. Optimal immunologic and weight recoveries in the first 6 months suggest increased effort to retain patients in care at this period. PMID:26889319

  15. TEMOZOLOMIDE FOR RECURRENT INTRACRANIAL EPENDYMOMA OF THE ADULT: PATTERNS OF RESPONSE, SURVIVAL AND CORRELATIONS WITH MGMT PROMOTER METHYLATION

    PubMed Central

    Soffietti, Riccardo; Bosa, Chiara; Bertero, Luca; Trevisan, Elisa; Cassoni, Paola; Morra, Isabella; Rudà, Roberta

    2014-01-01

    BACKGROUND: A variety of agents have been investigated with modest results in recurrent grade II and III ependymomas failing surgery and/or radiotherapy. Few data are available on the role of temozolomide (TMZ). We investigated patterns of response, outcome and correlations with MGMT promoter methylation in a cohort of patients with recurrent ependymomas of the adult receiving temozolomide as salvage therapy. METHODS: We retrospectively studied all patients aged ≥18 years with recurrent intracranial ependymoma, who received as part of their treatment standard temozolomide between 1999 and 2011. Clinical information were retrieved from the database and follow-up visits, while MRI images were reviewd by an investigator blind to patients' outcome. Response to TMZ on MRI was evaluated according to Macdonald Criteria. An analysis of MGMT gene promoter methylation by PCR was performed. RESULTS: We found 18 evaluable patients of whom 12 were males and 6 females, and 10 (56%) were of grade III and 8 (44%) of grade II. Tumor location at initial surgery was supratentorial in 11 (61%) patients and infratentorial in 7 (39%), and type of progression before TMZ was local in 10 (56%), local and spinal in 6 (33%) and spinal alone in 2 (11%). Median age was 42 years (18-61) and median KPS 70 (60-90). Previous treatments consisted of radiotherapy (either adjuvant or at relapse) in 17/18 (94%) patients, and chemotherapy (cisplatin + VP16, PCV, BCNU) in 6/18 (33%). A median of 8 cycles of TMZ (1-24) were administered. Best response to TMZ was as follows: CR 1/18 (5%) and PR 3/18 (17%), with an overall RR of 22%; SD 7/18 (39%) and PD 7/18 (39%). Maximum reponse in 3 out of 4 patients was observed after 10, 14 and 15 cycles, respectively. All 4 responding patients were chemotherapy-naive. Responses occurred in both anaplastic (2) and low grade (2) tumors. Median PFS was 9 months (1 month-13 years), while PFS 6 and 12 were 72% and 39%, respectively. Median OS was 31 months (3 months-14

  16. Disparities in Adverse Childhood Experiences among Sexual Minority and Heterosexual Adults: Results from a Multi-State Probability-Based Sample

    PubMed Central

    Andersen, Judith P; Blosnich, John

    2013-01-01

    Background Adverse childhood experiences (e.g., physical, sexual and emotional abuse, neglect, exposure to domestic violence, parental discord, familial mental illness, incarceration and substance abuse) constitute a major public health problem in the United States. The Adverse Childhood Experiences (ACE) scale is a standardized measure that captures multiple developmental risk factors beyond sexual, physical and emotional abuse. Lesbian, gay, and bisexual (i.e., sexual minority) individuals may experience disproportionately higher prevalence of adverse childhood experiences. Purpose To examine, using the ACE scale, prevalence of childhood physical, emotional, and sexual abuse and childhood household dysfunction among sexual minority and heterosexual adults. Methods Analyses were conducted using a probability-based sample of data pooled from three U.S. states’ Behavioral Risk Factor Surveillance System (BRFSS) surveys (Maine, Washington, Wisconsin) that administered the ACE scale and collected information on sexual identity (n = 22,071). Results Compared with heterosexual respondents, gay/lesbian and bisexual individuals experienced increased odds of six of eight and seven of eight adverse childhood experiences, respectively. Sexual minority persons had higher rates of adverse childhood experiences (IRR = 1.66 gay/lesbian; 1.58 bisexual) compared to their heterosexual peers. Conclusions Sexual minority individuals have increased exposure to multiple developmental risk factors beyond physical, sexual and emotional abuse. We recommend the use of the Adverse Childhood Experiences scale in future research examining health disparities among this minority population. PMID:23372755

  17. Age-specific survival of reintroduced swift fox in Badlands National Park and surrounding lands

    USGS Publications Warehouse

    Sasmal, Indrani; Klaver, Robert W.; Jenks, Jonathan A.; Schroeder, Greg M.

    2016-01-01

    In 2003, a reintroduction program was initiated at Badlands National Park (BNP), South Dakota, USA, with swift foxes (Vulpes velox) translocated from Colorado and Wyoming, USA, as part of a restoration effort to recover declining swift fox populations throughout its historical range. Estimates of age-specific survival are necessary to evaluate the potential for population growth of reintroduced populations. We used 7 years (2003–2009) of capture–recapture data of 243 pups, 29 yearlings, and 69 adult swift foxes at BNP and the surrounding area to construct Cormack–Jolly–Seber model estimates of apparent survival within a capture–mark–recapture framework using Program MARK. The best model for estimating recapture probabilities included no differences among age classes, greater recapture probabilities during early years of the monitoring effort than later years, and variation among spring, winter, and summer. Our top ranked survival model indicated pup survival differed from that of yearlings and adults and varied by month and year. The apparent annual survival probability of pups (0.47, SE = 0.10) in our study area was greater than the apparent annual survival probability of yearlings and adults (0.27, SE = 0.08). Our results indicate low survival probabilities for a reintroduced population of swift foxes in the BNP and surrounding areas. Management of reintroduced populations and future reintroductions of swift foxes should consider the effects of relative low annual survival on population demography.

  18. Why Probability?

    ERIC Educational Resources Information Center

    Weatherly, Myra S.

    1984-01-01

    Instruction in mathematical probability to enhance higher levels of critical and creative thinking with gifted students is described. Among thinking skills developed by such an approach are analysis, synthesis, evaluation, fluency, and complexity. (CL)

  19. Dispersal and survival of a polygynandrous passerine

    USGS Publications Warehouse

    Craig, Heather R.; Kendall, Steve J.; Wild, Teri C.; Powell, Abby N.

    2015-01-01

    Although sex biases in survival and dispersal are thought to be linked to avian mating systems, little is known about these demographic patterns in less common mating strategies such as polygynandry. We investigated breeding-site fidelity, natal philopatry, and apparent survival of the polygynandrous Smith's Longspur (Calcarius pictus) over a 7-yr period at 2 areas in Alaska's Brooks Range. We used capture–recapture histories of 243 color-banded adults and 431 juveniles to estimate annual survival and determined dispersal patterns from 34 adults that were found breeding within the study areas over multiple years. Most adults (88%) returned to nest in the same breeding neighborhood as in previous years; mean dispersal distance was 300.9 ± 74.2 m and did not differ between sexes. Juveniles exhibited low natal philopatry; only 4% of banded hatch-year birds were resighted as adults during subsequent years. Those that did return dispersed, on average, 1,674.4 ± 465.8 m from their natal nests (n = 6). Model-averaged survival estimates indicated that annual survival of adult females (50–58%) was only slightly lower than that of males (60–63%); juvenile survival was 41% but was paired with a low (13%) encounter probability. We attribute the lack of sex bias in adult dispersal to this species' polygynandrous mating strategy. Within this system, there are multiple mates within a breeding neighborhood. We argue that natural selection may favor females that remain on the same, familiar breeding site, because they do not have to disperse to a new area to find a suitable mate. Dispersal among breeding populations most likely occurs by juveniles returning as adults. Our findings support hypotheses that suggest a relationship between dispersal and mating strategy and provide some of the first insight into the demographic patterns of a polygynandrous passerine.

  20. Gender Differences in Survival among Adult Patients Starting Antiretroviral Therapy in South Africa: A Multicentre Cohort Study

    PubMed Central

    Cornell, Morna; Schomaker, Michael; Garone, Daniela Belen; Giddy, Janet; Hoffmann, Christopher J.; Lessells, Richard; Maskew, Mhairi; Prozesky, Hans; Wood, Robin; Johnson, Leigh F.; Egger, Matthias; Boulle, Andrew; Myer, Landon

    2012-01-01

    Background Increased mortality among men on antiretroviral therapy (ART) has been documented but remains poorly understood. We examined the magnitude of and risk factors for gender differences in mortality on ART. Methods and Findings Analyses included 46,201 ART-naïve adults starting ART between January 2002 and December 2009 in eight ART programmes across South Africa (SA). Patients were followed from initiation of ART to outcome or analysis closure. The primary outcome was mortality; secondary outcomes were loss to follow-up (LTF), virologic suppression, and CD4+ cell count responses. Survival analyses were used to examine the hazard of death on ART by gender. Sensitivity analyses were limited to patients who were virologically suppressed and patients whose CD4+ cell count reached >200 cells/µl. We compared gender differences in mortality among HIV+ patients on ART with mortality in an age-standardised HIV-negative population. Among 46,201 adults (65% female, median age 35 years), during 77,578 person-years of follow-up, men had lower median CD4+ cell counts than women (85 versus 110 cells/µl, p<0.001), were more likely to be classified WHO stage III/IV (86 versus 77%, p<0.001), and had higher mortality in crude (8.5 versus 5.7 deaths/100 person-years, p<0.001) and adjusted analyses (adjusted hazard ratio [AHR] 1.31, 95% CI 1.22–1.41). After 36 months on ART, men were more likely than women to be truly LTF (AHR 1.20, 95% CI 1.12–1.28) but not to die after LTF (AHR 1.04, 95% CI 0.86–1.25). Findings were consistent across all eight programmes. Virologic suppression was similar by gender; women had slightly better immunologic responses than men. Notably, the observed gender differences in mortality on ART were smaller than gender differences in age-standardised death rates in the HIV-negative South African population. Over time, non-HIV mortality appeared to account for an increasing proportion of observed mortality. The analysis was limited by missing

  1. Size-sex variation in survival rates and abundance of pig frogs, Rana grylio, in northern Florida wetlands

    USGS Publications Warehouse

    Wood, K.V.; Nichols, J.D.; Percival, H.F.; Hines, J.E.

    1998-01-01

    During 1991-1993, we conducted capture-recapture studies on pig frogs, Rana grylio, in seven study locations in northcentral Florida. Resulting data were used to test hypotheses about variation in survival probability over different size-sex classes of pig frogs. We developed multistate capture-recapture models for the resulting data and used them to estimate survival rates and frog abundance. Tests provided strong evidence of survival differences among size-sex classes, with adult females showing the highest survival probabilities. Adult males and juvenile frogs had lower survival rates that were similar to each other. Adult females were more abundant than adult males in most locations at most sampling occasions. We recommended probabilistic capture-recapture models in general, and multistate models in particular, for robust estimation of demographic parameters in amphibian populations.

  2. Diagnostic, treatment, and demographic factors influencing survival in a population-based study of adult glioma patients in the San Francisco Bay Area1

    PubMed Central

    Wrensch, Margaret; Rice, Terri; Miike, Rei; McMillan, Alex; Lamborn, Kathleen R.; Aldape, Kenneth; Prados, Michael D.

    2006-01-01

    We compare survival estimates for population-based glioma cases by using two diagnostic coding schemes, (1) the International Classification of Diseases, Oncology, second edition (ICD-O-2) as reported by the Surveillance, Epidemiology, and End Results (SEER) program and (2) central neuropathology review diagnosis based on the World Health Organization II classification. In addition, among review categories, we estimate survival in relation to several patient demographic and treatment factors. Eligible cases included adults residing in the San Francisco Bay SEER Area with newly diagnosed, histologically confirmed glioma during the years 1991–1994 and 1997–1999. The study group included participating subjects for whom subsequent central neuropathology review confirmed glioma. We determined treatments, vital status, and other factors by using registry, interview, medical record, and active follow-up data. Survival differences between anaplastic astrocytoma (AA) and astrocytoma were apparent from review diagnoses (median months of survival for AA, 13.0 [95% CI, 9.9–19.5], and astrocytoma, 101.3 [95% CI lower limit, 42.1; upper limit not yet reached]), but not with ICD-O-2 diagnoses reported by SEER (median months of survival for AA, 16.6 [95% CI, 12.0–20.7], and astrocytoma, not otherwise specified, 17.2 [95% CI, 10.6–71.6]). This finding emphasizes the need for improvements in coding for nonglioblastoma astrocytomas to provide better population survival estimates. When review diagnosis was used, younger age and resection (vs. biopsy) were statistically significant for all histology groups analyzed by multivariable Cox proportional hazard models. Additional statistically significant variables were as follows: among 517 glioblastoma patients, radiation treatment and being married; among 105 AA patients, inclusion of chemotherapy in the initial treatment; and among 106 patients with nonanaplastic oligodendroglial tumors, college education. Further consideration

  3. Trends in Esophageal Cancer Survival in United States Adults from 1973 to 2009: A SEER Database Analysis

    PubMed Central

    Njei, Basile; McCarty, Thomas R.; Birk, John W.

    2016-01-01

    Background The rise in incidence of esophageal cancer (EC) in the United States (U.S.) over the last four decades has been well documented; however, data on trends in long-term survival and impact on modern therapies associated with survival is lacking. Methods The Surveillance, Epidemiology, and End Results (SEER) database was queried to identify patients with confirmed EC. Cox proportional hazard regression was used to determine independent mortality factors. Results Of 93,167 patients diagnosed with EC between 1973 and 2009, 49% had a histologic diagnosis of esophageal adenocarcinoma (EAC). There was an increase (almost double) in the proportion of patients with adenocarcinoma from the 1970's to 2000's (n = 2,350; 35% to n = 32,212; 61%, p<0.001). Surgery was performed for localized disease in a majority of EC regardless of type (n = 46,683; 89%). Use of surgical treatment increased significantly over the study period (49% to 64%, p<0.001). There was also an increase in overall median survival (6 months versus 10 months, p<0.001) and 5-year survival rate (9% to 22%, p<0.001). Median survival increased consistently for EAC and squamous cell carcinoma (SCC) until the 1990's. After this period, median survival of EAC continued to increase more rapidly while SCC remained relatively stable. Conclusion A significant survival improvement in esophageal cancer was seen from 1973 to 2009, largely due to earlier detection at a curative stage and greater utilization of treatment modalities (especially surgery). Despite the rising prevalence, patients with EAC have better long-term survival outcomes than those SCC. PMID:26749521

  4. Patterns of practice and survival in a retrospective analysis of 1722 adult astrocytoma patients treated between 1985 and 2001 in 12 Italian radiation oncology centers

    SciTech Connect

    Magrini, Stefano Maria . E-mail: magrini@med.unibs.it; Ricardi, Umberto; Santoni, Riccardo; Krengli, Marco; Lupattelli, Marco; Cafaro, Ines; Scoccianti, Silvia; Menichelli, Claudia; Bertoni, Filippo; Enrici, Riccardo Maurizi; Tombolini, Vincenzo; Buglione, Michela; Pirtoli, Luigi

    2006-07-01

    Purpose: To analyze the patterns of practice and survival in a series of 1722 adult astrocytoma patients treated in 12 Italian radiotherapy centers. Methods and Materials: A total of 1722 patients were treated with postoperative radiotherapy (90% World Health Organization [WHO] Grade 3-4, 62% male, 44% aged >60 years, 25% with severe neurologic deficits, 44% after gross total resection, 52% with high-dose radiotherapy, and 16% with chemotherapy). Variations in the clinical-therapeutic features in three subsequent periods (1985 through 2001) were evaluated, along with overall survival for the different subgroups. Results: The proportion of women, of older patients, of those with worse neurologic performance status (NPS), with WHO Grade 4, and with smaller tumors increased with time, as did the proportion of those treated with radical surgery, hypofractionated radiotherapy, and more sophisticated radiotherapy techniques, after staging procedures progressively became more accurate. The main prognostic factors for overall survival were age, sex, neurologic performance status, WHO grade, extent of surgery, and radiation dose. Conclusions: Recently, broader selection criteria for radiotherapy were adopted, together with simpler techniques, smaller total doses, and larger fraction sizes for the worse prognostic categories. Younger, fit patients are treated more aggressively, more often in association with chemotherapy. Survival did not change over time. The accurate evaluation of neurologic status is therefore of utmost importance before the best treatment option for the individual patient is chosen.

  5. Green tea compound epigallo-catechin-3-gallate (EGCG) increases neuronal survival in adult hippocampal neurogenesis in vivo and in vitro.

    PubMed

    Ortiz-López, L; Márquez-Valadez, B; Gómez-Sánchez, A; Silva-Lucero, M D C; Torres-Pérez, M; Téllez-Ballesteros, R I; Ichwan, M; Meraz-Ríos, M A; Kempermann, G; Ramírez-Rodríguez, G B

    2016-05-13

    Epigallo-catechin-3-gallate (EGCG), found in the leaves of Camellia sinensis (green tea), has antioxidant- and scavenger-functions and acts neuroprotectively. It has been publicized as anti-aging remedy but data on potential cellular mechanisms are scarce. Recent studies claimed that EGCG specifically promotes neural precursor cell proliferation in the dentate gyrus of C57Bl/6 mice, without changes at the level of immature and mature new neurons. We here analyzed the effects of EGCG on adult hippocampal neurogenesis in male Balb/C mice and saw a different pattern. Two weeks of treatment with EGCG (0, 0.625, 1.25, 2.5, 5 and 10mg/kg) showed a dose-response curve that peaked at 2.5mg/kg of EGCG with significantly increased cell survival without affecting cell proliferation but decreasing apoptotic cells. Also, EGCG increased the population of doublecortin-(DCX)-expressing cells that comprises the late intermediate progenitor cells (type-2b and -3) as well as immature neurons. After EGCG treatment, the young DCX-positive neurons showed more elaborated dendritic trees. EGCG also significantly increased net neurogenesis in the adult hippocampus and increased the hippocampal levels of phospho-Akt. Ex vivo, EGCG exerted a direct effect on survival and neuronal differentiation of adult hippocampal precursor cells, which was absent, when PI3K, a protein upstream of Akt, was blocked. Our results thus support a pro-survival and a pro-neurogenic role of EGCG. In the context of the conflicting published results, however, potential genetic modifiers must be assumed. These might help to explain the overall variability of study results with EGCG. Our data do indicate, however, that natural compounds such as EGCG can in principle modulate brain plasticity. PMID:26917271

  6. Bimolecular recombination reactions: K-adiabatic and K-active forms of RRKM theory, nonstatistical aspects, low-pressure rates, and time-dependent survival probabilities with application to ozone. 2.

    PubMed

    Ghaderi, Nima; Marcus, R A

    2014-11-01

    We consider for bimolecular recombination reactions the K-adiabatic versus the K-active forms of RRKM theory, where K is the component of the total angular momentum along the axis of least moment of inertia of the recombination product. When that product is approximately a prolate symmetric top, with two moments of inertia of the product substantially larger than the third, K becomes a dynamically slowly varying quantity and the K-adiabatic form of RRKM theory is the appropriate version to use. Using classical trajectory results for the rate constant for ozone formation in the low-pressure region as an example, excellent agreement for the recombination rate constant k(rec) with the K-adiabatic RRKM theory is observed. Use of a two transition state (inner, outer TS) formalism also obviates any need for assessing recrossings in the exit channel. In contrast, the K-active form of RRKM theory for this system disagrees with the trajectory results by a factor of about 2.5. In this study we also consider the distribution of the (E, J) resolved time-dependent survival probabilities P(E, J, t) of the intermediate O3* formed from O + O2. It is calculated using classical trajectories. The initial conditions for classical trajectories were selected using action-angle variables and a total J representation for (E, J) resolved systems, as described in Part I.1 The difference between K-active and K-adiabatic treatments is reflected also in a difference of the K-active RRKM survival probability P(E, J, t) from its trajectory-based value and from its often non-single-exponential decay. It is shown analytically that krec (K-active) ≥ k(rec) (K-adiabatic), independent of the details of the TS (e.g., variational or fixed RRKM theory, 1-TS or 2-TS). Nonstatistical effects for O3* formation include a small initial recrossing of the transition state, a slow (several picoseconds) equipartitioning of energy among the two O-O bonds of the newly formed O3*, and a small nondissociation (a

  7. Survivability Versus Time

    NASA Technical Reports Server (NTRS)

    Joyner, James J., Sr.

    2014-01-01

    Develop Survivability vs Time Model as a decision-evaluation tool to assess various emergency egress methods used at Launch Complex 39B (LC 39B) and in the Vehicle Assembly Building (VAB) on NASAs Kennedy Space Center. For each hazard scenario, develop probability distributions to address statistical uncertainty resulting in survivability plots over time and composite survivability plots encompassing multiple hazard scenarios.

  8. Effects of crude oil exposure on bioaccumulation of polycyclic aromatic hydrocarbons and survival of adult and larval stages of gelatinous zooplankton.

    PubMed

    Almeda, Rodrigo; Wambaugh, Zoe; Chai, Chao; Wang, Zucheng; Liu, Zhanfei; Buskey, Edward J

    2013-01-01

    Gelatinous zooplankton play an important role in marine food webs both as major consumers of metazooplankton and as prey of apex predators (e.g., tuna, sunfish, sea turtles). However, little is known about the effects of crude oil spills on these important components of planktonic communities. We determined the effects of Louisiana light sweet crude oil exposure on survival and bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) in adult stages of the scyphozoans Pelagia noctiluca and Aurelia aurita and the ctenophore Mnemiopsis leidyi, and on survival of ephyra larvae of A. aurita and cydippid larvae of M. leidyi, in the laboratory. Adult P. noctiluca showed 100% mortality at oil concentration ≥20 µL L(-1) after 16 h. In contrast, low or non-lethal effects were observed on adult stages of A. aurita and M. leidyi exposed at oil concentration ≤25 µL L(-1) after 6 days. Survival of ephyra and cydippid larva decreased with increasing crude oil concentration and exposition time. The median lethal concentration (LC50) for ephyra larvae ranged from 14.41 to 0.15 µL L(-1) after 1 and 3 days, respectively. LC50 for cydippid larvae ranged from 14.52 to 8.94 µL L(-1) after 3 and 6 days, respectively. We observed selective bioaccumulation of chrysene, phenanthrene and pyrene in A. aurita and chrysene, pyrene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, and benzo[a]anthracene in M. leidyi. Overall, our results indicate that (1) A. aurita and M. leidyi adults had a high tolerance to crude oil exposure compared to other zooplankton, whereas P. noctiluca was highly sensitive to crude oil, (2) larval stages of gelatinous zooplankton were more sensitive to crude oil than adult stages, and (3) some of the most toxic PAHs of crude oil can be bioaccumulated in gelatinous zooplankton and potentially be transferred up the food web and contaminate apex predators. PMID:24116004

  9. Effects of Crude Oil Exposure on Bioaccumulation of Polycyclic Aromatic Hydrocarbons and Survival of Adult and Larval Stages of Gelatinous Zooplankton

    PubMed Central

    Almeda, Rodrigo; Wambaugh, Zoe; Chai, Chao; Wang, Zucheng; Liu, Zhanfei; Buskey, Edward J.

    2013-01-01

    Gelatinous zooplankton play an important role in marine food webs both as major consumers of metazooplankton and as prey of apex predators (e.g., tuna, sunfish, sea turtles). However, little is known about the effects of crude oil spills on these important components of planktonic communities. We determined the effects of Louisiana light sweet crude oil exposure on survival and bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) in adult stages of the scyphozoans Pelagia noctiluca and Aurelia aurita and the ctenophore Mnemiopsis leidyi, and on survival of ephyra larvae of A. aurita and cydippid larvae of M. leidyi, in the laboratory. Adult P. noctiluca showed 100% mortality at oil concentration ≥20 µL L−1 after 16 h. In contrast, low or non-lethal effects were observed on adult stages of A. aurita and M. leidyi exposed at oil concentration ≤25 µL L−1 after 6 days. Survival of ephyra and cydippid larva decreased with increasing crude oil concentration and exposition time. The median lethal concentration (LC50) for ephyra larvae ranged from 14.41 to 0.15 µL L−1 after 1 and 3 days, respectively. LC50 for cydippid larvae ranged from 14.52 to 8.94 µL L−1 after 3 and 6 days, respectively. We observed selective bioaccumulation of chrysene, phenanthrene and pyrene in A. aurita and chrysene, pyrene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, and benzo[a]anthracene in M. leidyi. Overall, our results indicate that (1) A. aurita and M. leidyi adults had a high tolerance to crude oil exposure compared to other zooplankton, whereas P. noctiluca was highly sensitive to crude oil, (2) larval stages of gelatinous zooplankton were more sensitive to crude oil than adult stages, and (3) some of the most toxic PAHs of crude oil can be bioaccumulated in gelatinous zooplankton and potentially be transferred up the food web and contaminate apex predators. PMID:24116004

  10. The Time to Clearance of Peripheral Blood Blasts Predicts Complete Remission and Survival in Chinese Adults with Acute Myeloid Leukemia.

    PubMed

    Li, Xiaoyang; Zhu, Hongming; Zhang, Yunxiang; Zhao, Weili; Mi, Jianqing; Hu, Jiong; Li, Junmin

    2016-01-01

    The value of clearance of peripheral blood blasts (PBB) as a predictor of outcomes in acute myeloid leukemia (AML) is controversial. To investigate the prognostic significance of the time to clearance of PBB after induction in Chinese patients with AML, a retrospective analysis of 146 patients with newly diagnosed AML at Shanghai Ruijin Hospital was performed. Patients were categorized into early blast clearance (EBC; ≤5 days) and delayed blast clearance (DBC; >5 days) groups based on a receiver operating characteristic analysis. Complete remission (CR) after induction chemotherapy was related to the time to clearance of PBB (p < 0.001). Relapse-free survival (RFS; p = 0.003) and overall survival (p < 0.001) were longer in the EBC group. Multivariate analysis demonstrated that the time to clearance of PBB and cytogenetic risk independently predicted CR and RFS. Early clearance of PBB after induction chemotherapy can be a significant predictor of survival outcomes in AML patients. PMID:26967450

  11. Are adult nonbreeders prudent parents? The kittiwake model

    USGS Publications Warehouse

    Cam, E.; Hines, J.E.; Monnat, J.-Y.; Nichols, J.D.; Danchin, E.

    1998-01-01

    Understanding evolutionary consequences of intermittent breeding (non-breeding in individuals that previously bred) requires investigation of the relationships between adult breeding state and two demographic parameters: survival probability and subsequent breeding probability. One major difficulty raised by comparing the demographic features of breeders and nonbreeders as estimated from capture-recapture data is that breeding state is often suspected to influence recapture or resighting probability. We used multistate capture-recapture models to test the hypothesis of equal recapture probabilities for breeding and nonbreeding Kittiwakes and found no evidence of an effect of breeding state on this parameter. The same method was used to test whether reproductive state affects survival probability. Nonbreeding individuals have lower survival rates than breeders. Moreover, nonbreeders have a higher probability of being nonbreeders the following year than do breeders. State-specific survival rates and transition probabilities vary from year to year, but temporal variations of survival and transition probabilities of breeders and nonbreeders are in parallel (on a logit scale). These inferences led us to conclude that nonbreeders tend to be lower quality individuals. The effect of sex was also investigated: males and females do not differ with respect to survival probabilities when reproductive state is taken into account. Similarly, there is no effect of sex on transition probabilities between reproductive states.

  12. Anthropogenic host plant expansion leads a nettle-feeding butterfly out of the forest: consequences for larval survival and developmental plasticity in adult morphology

    PubMed Central

    Merckx, Thomas; Serruys, Mélanie; Van Dyck, Hans

    2015-01-01

    Recent anthropogenic eutrophication has meant that host plants of nettle-feeding insects became quasi-omnipresent in fertile regions of Western Europe. However, host plant resource quality – in terms of microclimate and nutritional value – may vary considerably between the ‘original’ forest habitat and ‘recent’ agricultural habitat. Here, we compared development in both environmental settings using a split-brood design, so as to explore to what extent larval survival and adult morphology in the nettle-feeding butterfly Aglais urticae are influenced by the anthropogenic environment. Nettles along field margins had higher C/N ratios and provided warmer microclimates to larvae. Larvae developed 20% faster and tended to improve their survival rates, on the agricultural land compared to woodland. Our split-brood approach indicated plastic responses within families, but also family effects in the phenotypic responses. Adult males and females had darker wing pigmentation in the drier and warmer agricultural environment, which contrasts with the thermal melanism hypothesis. Developmental plasticity in response to this microclimatically different and more variable habitat was associated with a broader phenotypic parameter space for the species. Both habitat expansion and developmental plasticity are likely contributors to the ecological and evolutionary success of these nettle-feeding insects in anthropogenic environments under high nitrogen load. PMID:25926881

  13. Neuron-enriched cultures of adult rat dorsal root ganglia: establishment, characterization, survival, and neuropeptide expression in response to trophic factors.

    PubMed

    Grothe, C; Unsicker, K

    1987-01-01

    It is unknown whether adult dorsal root ganglion (DRG) neurons require trophic factors for their survival and maintenance of neuropeptide phenotypes. We have established and characterized neuron-enriched cultures of adult rat DRGs and investigated their responses to nerve growth factor (NGF), ciliary neuronotrophic factor (CNTF), pig brain extract (PBE, crude fraction of brain-derived neuronotrophic factor, BDNF), and laminin (LN). DRGs were dissected from levels C1 through L6 and dissociated and freed from myelin fragments and most satellite (S-100-immunoreactive) cells by centrifugation on Percoll and preplating. The enriched neurons, characterized by their morphology and immunoreactivity for neuron-specific enolase, constituted a population representative of the in vivo situation with regard to expression of substance P (SP), somatostatin (SOM), and cholecystokinin-8 (CCK) immunoreactivities. In the absence of trophic factors and using polyornithine (PORN) as a substratum, 60-70% of the neurons present initially (0.5 days) had died after 7 days. LN as a substratum did not prevent a 30% loss of neurons up to day 4.5, but it subsequently maintained DRG neurons at a plateau. This behavior might reflect a cotrophic effect of LN and factors provided by non-neuronal cells, whose proliferation between 4.5 and 7 days could not be prevented by addition of mitotic inhibitors of gamma-irradiation. CNTF, but not NGF, slightly enhanced survival at 7 days on either PORN or LN. No neuronal losses were found in non-enriched cultures or when enriched neurons were supplemented with PBE, indicating that non-neuronal cells and PBE provide factor(s) essential for adult DRG neuron survival. Proportions of SP-, SOM-, and CCK-immunoreactive cells were unaltered under any experimental condition, with the exception of a numerical decline in SP cells in 7-day cultures with LN, but not PORN, as the substratum. Our data, considered in the context of recent in vivo and vitro studies, suggest

  14. Transplantation of bone marrow stromal cells enhances infiltration and survival of CNP and Schwann cells to promote axonal sprouting following complete transection of spinal cord in adult rats

    PubMed Central

    Ding, Peng; Yang, Zhiyong; Wang, Weimin; Wang, Jinkun; Xue, Liping

    2014-01-01

    This study aimed to investigate the roles of bone marrow stromal cells (BMSCs) in promoting axonal regeneration after complete transection of spinal cord in adult rats. Transplantation was done 9 days after injury. Only a few BMSCs were detected at the injury site 8 weeks after transplantation, yet there was robust growth of axons. The scarcity of surviving BMSCs may attribute to the adverse conditions in their ambient environment. In this connection, the immediate accumulation of a large number of macrophages/reactive microglia following BMSCs transplantation and subsequent cavitation of tissues may be detrimental to their survival. An unexpected finding following BMSCs transplantation was the marked increase in the nestin, GFAP, NF200, olig 3 and CNP positive cells at the injury site. Immunoelectron microscopy showed CNP cells were oval or fibroblast-like and had multiple perineurial-like compartments with long extending filopodia. The spatial relationship between regenerating axons and CNP-positive cells was also confirmed by double immunofluorescence staining. Our results suggest that transplantation of BMSCs elicits the influx and survival of local cells including CNP positive cells and Schwann cells into injury site, which provide structural support for the axon regeneration and remyelination after spinal cord injury. PMID:24936216

  15. The Bone Morphogenetic Protein Type Ib Receptor Is a Major Mediator of Glial Differentiation and Cell Survival in Adult Hippocampal Progenitor Cell Culture

    PubMed Central

    Brederlau, A.; Faigle, R.; Elmi, M.; Zarebski, A.; Sjöberg, S.; Fujii, M.; Miyazono, K.; Funa, K.

    2004-01-01

    Bone morphogenetic proteins (BMPs) act as growth regulators and inducers of differentiation. They transduce their signal via three different type I receptors, termed activin receptor-like kinase 2 (Alk2), Alk3, or bone morphogenetic protein receptor Ia (BMPRIa) and Alk6 or BMPRIb. Little is known about functional differences between the three type I receptors. Here, we have investigated consequences of constitutively active (ca) and dominant negative (dn) type I receptor overexpression in adult-derived hippocampal progenitor cells (AHPs). The dn receptors have a nonfunctional intracellular but functional extracellular domain. They thus trap BMPs that are endogenously produced by AHPs. We found that effects obtained by overexpression of dnAlk2 and dnAlk6 were similar, suggesting similar ligand binding patterns for these receptors. Thus, cell survival was decreased, glial fibrillary acidic protein (GFAP) expression was reduced, whereas the number of oligodendrocytes increased. No effect on neuronal differentiation was seen. Whereas the expression of Alk2 and Alk3 mRNA remained unchanged, the Alk6 mRNA was induced after impaired BMP signaling. After dnAlk3 overexpression, cell survival and astroglial differentiation increased in parallel to augmented Alk6 receptor signaling. We conclude that endogenous BMPs mediate cell survival, astroglial differentiation and the suppression of oligodendrocytic cell fate mainly via the Alk6 receptor in AHP culture. PMID:15194807

  16. Divorce Is a Part of My Life . . . Resilience, Survival, and Vulnerability: Young Adults' Perception of the Implications of Parental Divorce

    ERIC Educational Resources Information Center

    Eldar-Avidan, Dorit; Haj-Yahia, Muhammad M.; Greenbaum, Charles W.

    2009-01-01

    A qualitative study among 22 young adults (20-25 years old) whose parents divorced during their childhood was conducted in Israel, using semi-structured, in-depth, open-ended interviews. Qualitative data analysis led to identification of three profiles, aiming at a grounded theoretical conceptualization. Three core themes were identified: the…

  17. Effect of Locally Administered Ciliary Neurotrophic Factor on the Survival of Transected and Repaired Adult Sheep Facial Nerve

    PubMed Central

    Al Abri, Rashid; Kolethekkat, Arif Ali; Kelleher, Michael O.; Myles, Lynn M.; Glasby, Michael A.

    2014-01-01

    Objective to determine whether the administration of Ciliary Neurotrophic Factor (CNTF) at the site of repaired facial nerve enhances regeneration in the adult sheep model. Methods Ten adult sheep were divided into 2 groups: control and study group (CNTF group). In the CNTF group, the buccal branch of the facial nerve was transected and then repaired by epineural sutures. CNTF was injected over the left depressor labii maxillaris muscle in the vicinity of the transected and repaired nerve for 28 days under local anesthesia. In the CNTF group, the sheep were again anesthetized after nine months and the site of facial nerve repair was exposed. Detailed electrophysiological, tension experiments and morphometric studies were carried out and then analyzed statistically. Results The skin CV min, refractory period, Jitter and tension parameters were marginally raised in the CNTF group than the control but the difference was statistically insignificant between the two groups. Morphometric indices also did not show any significant changes in the CNTF group. Conclusion CNTF has no profound effect on neuronal regeneration of adult sheep animal model. Keywords CNTF; Neurtrophic factors; Sheep; Facial nerve; Regeneration. PMID:24936272

  18. TGF-β Is Required for Vascular Barrier Function, Endothelial Survival and Homeostasis of the Adult Microvasculature

    PubMed Central

    Maharaj, Arindel S. R.; Sekiyama, Eiichi; Maldonado, Angel E.; D'Amore, Patricia A.

    2009-01-01

    Pericyte-endothelial cell (EC) interactions are critical to both vascular development and vessel stability. We have previously shown that TGF-β signaling between EC and mural cells participates in vessel stabilization in vitro. We therefore investigated the role of TGF-β signaling in maintaining microvessel structure and function in the adult mouse retinal microvasculature. TGF-β signaling was inhibited by systemic expression of soluble endoglin (sEng) and inhibition was demonstrated by reduced phospho-smad2 in the adult retina. Blockade of TGF-β signaling led to increased vascular and neural cell apoptosis in the retina, which was associated with decreased retinal function, as measured by electroretinogram (ERG). Perfusion of the inner retinal vasculature was impaired and was accompanied by defective autoregulation and loss of capillary integrity. Fundus angiography and Evans blue permeability assay revealed a breakdown of the blood-retinal-barrier that was characterized by decreased association between the tight junction proteins zo-1 and occludin. Inhibition of TGF-β signaling in cocultures of EC and 10T1/2 cells corroborated the in vivo findings, with impaired EC barrier function, dissociation of EC from 10T1/2 cells, and endothelial cell death, supporting the role of EC-mesenchymal interactions in TGF-β signaling. These results implicate constitutive TGF-β signaling in maintaining the integrity and function of the adult microvasculature and shed light on the potential role of TGF-β signaling in vasoproliferative and vascular degenerative retinal diseases. PMID:19340291

  19. Disparities in Stage at Diagnosis, Treatment, and Survival in Nonelderly Adult Patients With Cancer According to Insurance Status

    PubMed Central

    Walker, Gary V.; Grant, Stephen R.; Guadagnolo, B. Ashleigh; Hoffman, Karen E.; Smith, Benjamin D.; Koshy, Matthew; Allen, Pamela K.; Mahmood, Usama

    2014-01-01

    Purpose The purpose of this study was to determine the association of insurance status with disease stage at presentation, treatment, and survival among the top 10 most deadly cancers using the SEER database. Patients and Methods A total of 473,722 patients age 18 to 64 years who were diagnosed with one of the 10 most deadly cancers in the SEER database from 2007 to 2010 were analyzed. A Cox proportional hazards model was used for multivariable analyses to assess the effect of patient and tumor characteristics on cause-specific death. Results Overall, patients with non-Medicaid insurance were less likely to present with distant disease (16.9%) than those with Medicaid coverage (29.1%) or without insurance coverage (34.7%; P < .001). Patients with non-Medicaid insurance were more likely to receive cancer-directed surgery and/or radiation therapy (79.6%) compared with those with Medicaid coverage (67.9%) or without insurance coverage (62.1%; P < .001). In a Cox regression that adjusted for age, race, sex, marital status, residence, percent of county below federal poverty level, site, stage, and receipt of cancer-directed surgery and/or radiation therapy, patients were more likely to die as a result of their disease if they had Medicaid coverage (hazard ratio [HR], 1.44; 95% CI, 1.41 to 1.47; P < .001) or no insurance (HR, 1.47; 95% CI, 1.42 to 1.51; P < .001) compared with non-Medicaid insurance. Conclusion Among patients with the 10 most deadly cancers, those with Medicaid coverage or without insurance were more likely to present with advanced disease, were less likely to receive cancer-directed surgery and/or radiation therapy, and experienced worse survival. PMID:25092774

  20. Reporting Errors in Siblings’ Survival Histories and Their Impact on Adult Mortality Estimates: Results From a Record Linkage Study in Senegal

    PubMed Central

    Helleringer, Stéphane; Pison, Gilles; Kanté, Almamy M.; Duthé, Géraldine; Andro, Armelle

    2014-01-01

    Estimates of adult mortality in countries with limited vital registration (e.g., sub-Saharan Africa) are often derived from information about the survival of a respondent’s siblings. We evaluated the completeness and accuracy of such data through a record linkage study conducted in Bandafassi, located in southeastern Senegal. We linked at the individual level retrospective siblings’ survival histories (SSH) reported by female respondents (n = 268) to prospective mortality data and genealogies collected through a health and demographic surveillance system (HDSS). Respondents often reported inaccurate lists of siblings. Additions to these lists were uncommon, but omissions were frequent: respondents omitted 3.8 % of their live sisters, 9.1 % of their deceased sisters, and 16.6 % of their sisters who had migrated out of the DSS area. Respondents underestimated the age at death of the siblings they reported during the interview, particularly among siblings who had died at older ages (≥45 years). Restricting SSH data to person-years and events having occurred during a recent reference period reduced list errors but not age and date errors. Overall, SSH data led to a 20 % underestimate of 45q15 relative to HDSS data. Our study suggests new quality improvement strategies for SSH data and demonstrates the potential use of HDSS data for the validation of “unconventional” demographic techniques. PMID:24493063

  1. Effects of salinity on egg and fecal pellet production, development and survival, adult sex ratio and total life span in the calanoid copepod, Acartia tonsa: a laboratory study

    NASA Astrophysics Data System (ADS)

    Shayegan, Majid; Esmaeili Fereidouni, Abolghasem; Agh, Naser; Jani Khalili, Khosrow

    2016-07-01

    The effects of salinity on the copepod, Acartia tonsa in terms of daily egg production rate (EPR), hatching success, fecal pellet production rate (FPR), naupliar development time and survival, sex ratio, and total life span were determined in laboratory conditions through three experiments. In experiment 1, EPR, hatching success, and FPR of individual females were monitored at salinities of 13, 20, 35 and 45 during short-periods (seven consecutive days). Results show EPR was affected by salinity with the highest outputs recorded at 20 and 35, respectively, which were considerably higher than those at 13 and 45. Mean FPR was also higher in 35 and 20. In experiment 2, the same parameters were evaluated over total life span of females (long-term study). The best EPR and FPR were observed in 35, which was statistically higher than at 13 and 20. In experiment 3, survival rates of early nauplii until adult stage were lowest at a salinity of 13. The development time increased with increasing of salinity. Female percentage clearly decreased with increasing salinity. Higher female percentages (56.7% and 52.2%, respectively) were significantly observed at two salinities of 13 and 20 compared to that at 35 (25%). Total longevity of females was not affected by salinity increment. Based on our results, for mass culture we recommend that a salinity of 35 be adopted due to higher reproductive performances, better feeding, and faster development of A. tonsa.

  2. Effects of salinity on egg and fecal pellet production, development and survival, adult sex ratio and total life span in the calanoid copepod, Acartia tonsa: a laboratory study

    NASA Astrophysics Data System (ADS)

    Shayegan, Majid; Esmaeili Fereidouni, Abolghasem; Agh, Naser; Jani Khalili, Khosrow

    2016-01-01

    The effects of salinity on the copepod, Acartia tonsa in terms of daily egg production rate (EPR), hatching success, fecal pellet production rate (FPR), naupliar development time and survival, sex ratio, and total life span were determined in laboratory conditions through three experiments. In experiment 1, EPR, hatching success, and FPR of individual females were monitored at salinities of 13, 20, 35 and 45 during short-periods (seven consecutive days). Results show EPR was affected by salinity with the highest outputs recorded at 20 and 35, respectively, which were considerably higher than those at 13 and 45. Mean FPR was also higher in 35 and 20. In experiment 2, the same parameters were evaluated over total life span of females (long-term study). The best EPR and FPR were observed in 35, which was statistically higher than at 13 and 20. In experiment 3, survival rates of early nauplii until adult stage were lowest at a salinity of 13. The development time increased with increasing of salinity. Female percentage clearly decreased with increasing salinity. Higher female percentages (56.7% and 52.2%, respectively) were significantly observed at two salinities of 13 and 20 compared to that at 35 (25%). Total longevity of females was not affected by salinity increment. Based on our results, for mass culture we recommend that a salinity of 35 be adopted due to higher reproductive performances, better feeding, and faster development of A. tonsa.

  3. Survival and behavioral effects of exposure to a hydrokinetic turbine on juvenile Atlantic salmon and adult American shad

    USGS Publications Warehouse

    Castro-Santos, Theodore R.; Haro, Alex

    2015-01-01

    This paper describes a series of experiments designed to measure the effect of exposure to a full-scale, vertical axis hydrokinetic turbine on downstream migrating juvenile Atlantic salmon (N=75) and upstream migrating adult American shad (N=208). Controlled studies were performed in a large-scale, open-channel flume, and all individuals approached the turbine under volitional control. No injuries were observed, and there was no measurable increase in mortality associated with turbine passage. Exposure to the turbine elicited behavioral responses from both species, however, with salmon passing primarily over the downrunning blades. Shad movement was impeded by the device, as indicated by fewer attempts of shorter duration and reduced distance of ascent up the flume. More work should be performed in both laboratory and field conditions to determine to what extent these effects are likely to influence free-swimming fish.

  4. Survival estimates for Florida manatees from the photo-identification of individuals

    USGS Publications Warehouse

    Langtimm, C.A.; Beck, C.A.; Edwards, H.H.; Fick-Child, K. J.; Ackerman, B.B.; Barton, S.L.; Hartley, W.C.

    2004-01-01

    We estimated adult survival probabilities for the endangered Florida manatee (Trichechus manatus latirostris) in four regional populations using photo-identification data and open-population capture-recapture statistical models. The mean annual adult survival probability over the most recent 10-yr period of available estimates was as follows: Northwest - 0.956 (SE 0.007), Upper St. Johns River - 0.960 (0.011), Atlantic Coast - 0.937 (0.008), and Southwest - 0.908 (0.019). Estimates of temporal variance independent of sampling error, calculated from the survival estimates, indicated constant survival in the Upper St. Johns River, true temporal variability in the Northwest and Atlantic Coast, and large sampling variability obscuring estimates for the Southwest. Calf and subadult survival probabilities were estimated for the Upper St. Johns River from the only available data for known-aged individuals: 0.810 (95% CI 0.727-0.873) for 1st year calves, 0.915 (0.827-0.960) for 2nd year calves, and 0.969 (0.946-0.982) for manatee 3 yr or older. These estimates of survival probabilities and temporal variance, in conjunction with estimates of reproduction probabilities from photoidentification data can be used to model manatee population dynamics, estimate population growth rates, and provide an integrated measure of regional status.

  5. Modeling survival and mark loss in molting animals: recapture, dead recoveries, and exuvia recoveries.

    PubMed

    Besnard, Aurtlien; Piry, Sylvain; Berthier, Karine; Lebreton, Jean-Dominique; Streiff, Réjane

    2007-02-01

    Capture-mark-recapture (CMR) analyses aim primarily at estimating relevant life history parameters, despite the fact that some individuals are not always recaptured, even if alive on the study site. Applying such approaches to species with a complex life cycle, such as insects, remains challenging because each change of stage tends to cause mark loss through molting. We developed a multistate model based on three exclusive events ("dead", "surviving and molting", and "surviving and staying in the same larval stage") to estimate probabilities of survival and mark loss. Estimates of biologically relevant parameters were derived from those of the probabilities of transition between these states. The model was applied to data from radio-tracking diodes glued on grasshoppers. The estimates of recapture probabilities decreased throughout the season for animals remaining alive, while the detection of dead animals and lost diodes was exhaustive. The survival probability was higher for larvae than for adults (0.98 vs. 0.96), and mark loss was stronger in larvae than in adults (0.09 vs. 0.06). We show that the survival rate of a species with a high rate of mark loss can be estimated using multistate models, provided that marks can be recovered after being lost. These models are flexible enough to test for several effects that potentially affect survival and mark loss probabilities. PMID:17479747

  6. Limited Lung Function: Impact of Reduced Peak Expiratory Flow on Health Status, Health-Care Utilization, and Expected Survival in Older Adults

    PubMed Central

    Roberts, Melissa H.; Mapel, Douglas W.

    2012-01-01

    The authors examined whether peak expiratory flow (PEF) is a valid measure of health status in older adults. Survey and test data from the 2006 and 2008 cycles of the Health and Retirement Study, a longitudinal study of US adults over age 50 years (with biennial surveys initiated in 1992), were used to develop predicted PEF regression models and to examine relations between low PEF values and other clinical factors. Low PEF (<80% of predicted value) was prevalent among persons with chronic conditions, including frequent pain, obstructive lung disease, heart disease, diabetes, and psychological distress. Persons with higher physical disability scores had substantially higher adjusted odds of having low PEF, on par with those for conditions known to be associated with poor health (cancer, heart disease, and stroke). In a multivariate regression model for difficulty with mobility, PEF remained an independent factor (odds ratio (OR) = 1.69, 95% confidence interval (CI): 1.53, 1.86). Persons with low PEF in 2006 were more likely to be hospitalized (OR = 1.26, 95% CI: 1.10, 1.43) within the subsequent 2 years and to estimate their chances of surviving for 10 or more years at less than 50% (OR = 1.69, 95% CI: 1.24, 2.30). PEF is a valid measure of health status in older persons, and low PEF is an independent predictor of hospitalization and poor subjective mortality assessment. PMID:22759722

  7. Multidimensional Geriatric Prognostic Index, Based on a Geriatric Assessment, for Long-Term Survival in Older Adults in Korea.

    PubMed

    Jung, Hee-Won; Kim, Jin Won; Han, Ji Won; Kim, Kayoung; Kim, Jee Hyun; Kim, Kwang-Il; Kim, Cheol-Ho; Kim, Ki Woong

    2016-01-01

    The patient´s survival estimate is important for clinical decision-making, especially in frail patients with multimorbidities. We aimed to develop a multidimensional geriatric prognosis index (GPI) for 3- and 5-year mortality in community-dwelling elderly and to validate the GPI in a separate hospital-based population. The GPI was constructed using data for 988 participants in the Korean Longitudinal Study on Health and Aging (KLoSHA) and cross-validated with 1109 patients who underwent a geriatric assessment at the Seoul National University Bundang Hospital (SNUBH). The GPI, with a total possible score of 8, included age, gender, activities of daily living, instrumental activities of daily living, comorbidities, mood, cognitive function, and nutritional status. During the 5-year observation period, 179 KLoSHA participants (18.1%) and 340 SNUBH patients (30.7%) died. The c-indices for 3- and 5-year mortality were 0.78 and 0.80, respectively, in the KLoSHA group and 0.73 and 0.80, respectively, in the SNUBH group. Positive linear trends were observed for GPI scores and both 3- and 5-year mortality in both groups. In conclusions, using common components of a geriatric assessment, the GPI can stratify the risk of 3- and 5-year mortality in Korean elderly people both in the community and hospital. PMID:26771562

  8. Multidimensional Geriatric Prognostic Index, Based on a Geriatric Assessment, for Long-Term Survival in Older Adults in Korea

    PubMed Central

    Jung, Hee-Won; Han, Ji Won; Kim, Kayoung; Kim, Jee Hyun; Kim, Kwang-Il; Kim, Cheol-Ho

    2016-01-01

    The patient´s survival estimate is important for clinical decision-making, especially in frail patients with multimorbidities. We aimed to develop a multidimensional geriatric prognosis index (GPI) for 3- and 5-year mortality in community-dwelling elderly and to validate the GPI in a separate hospital-based population. The GPI was constructed using data for 988 participants in the Korean Longitudinal Study on Health and Aging (KLoSHA) and cross-validated with 1109 patients who underwent a geriatric assessment at the Seoul National University Bundang Hospital (SNUBH). The GPI, with a total possible score of 8, included age, gender, activities of daily living, instrumental activities of daily living, comorbidities, mood, cognitive function, and nutritional status. During the 5-year observation period, 179 KLoSHA participants (18.1%) and 340 SNUBH patients (30.7%) died. The c-indices for 3- and 5-year mortality were 0.78 and 0.80, respectively, in the KLoSHA group and 0.73 and 0.80, respectively, in the SNUBH group. Positive linear trends were observed for GPI scores and both 3- and 5-year mortality in both groups. In conclusions, using common components of a geriatric assessment, the GPI can stratify the risk of 3- and 5-year mortality in Korean elderly people both in the community and hospital. PMID:26771562

  9. Postfledging survival of European starlings

    USGS Publications Warehouse

    Krementz, D.G.; Nichols, J.D.; Hines, J.E.

    1989-01-01

    We tested the hypotheses that mass at fledging and fledge date within the breeding season affect postfledging survival in European Starlings (Sturnus vulgaris). Nestlings were weighed on day 18 after hatch and tagged with individually identifiable patagial tags. Fledge date was recorded. Marked fledglings were resighted during weekly two-day intensive observation periods for 9 weeks postfledging. Post-fledging survival and sighting probabilities were estimated for each of four groups (early or late fledging by heavy or light fledging mass). Body mass was related to post-fledging survival for birds that fledged early. Results were not clear-cut for relative fledge date, although there was weak evidence that this also influenced survival. Highest survival probability estimates occurred in the EARLY-HEAVY group, while the lowest survival estimate occurred in the LATE-LIGHT group. Sighting probabilities differed significantly among groups, emphasizing the need to estimate and compare survival using models which explicitly incorporate sighting probabilities.

  10. A prognostic model for survival after salvage treatment with FLAG-Ida +/- gemtuzumab-ozogamicine in adult patients with refractory/relapsed acute myeloid leukaemia.

    PubMed

    Bergua, Juan M; Montesinos, Pau; Martinez-Cuadrón, David; Fernández-Abellán, Pascual; Serrano, Josefina; Sayas, María J; Prieto-Fernandez, Julio; García, Raimundo; García-Huerta, Ana J; Barrios, Manuel; Benavente, Celina; Pérez-Encinas, Manuel; Simiele, Adriana; Rodríguez-Macias, Gabriela; Herrera-Puente, Pilar; Rodríguez-Veiga, Rebeca; Martínez-Sánchez, María P; Amador-Barciela, María L; Riaza-Grau, Rosalía; Sanz, Miguel A

    2016-09-01

    The combination of fludarabine, cytarabine, idarubicin, and granulocyte colony-stimulating factor (FLAG-Ida) is widely used in relapsed/refractory acute myeloid leukaemia (AML). We retrospectively analysed the results of 259 adult AML patients treated as first salvage with FLAG-Ida or FLAG-Ida plus Gentuzumab-Ozogamicin (FLAGO-Ida) of the Programa Español de Tratamientos en Hematología (PETHEMA) database, developing a prognostic score system of survival in this setting (SALFLAGE score). Overall, 221 patients received FLAG-Ida and 38 FLAGO-Ida; 92 were older than 60 years. The complete remission (CR)/CR with incomplete blood count recovery (CRi) rate was 51%, with 9% of induction deaths. Three covariates were associated with lower CR/CRi: high-risk cytogenetics and t(8;21) at diagnosis, no previous allogeneic stem cell transplantation (allo-SCT) and relapse-free interval <1 year. Allo-SCT was performed in second CR in 60 patients (23%). The median overall survival (OS) of the entire cohort was 0·7 years, with 22% OS at 5-years. Four independent variables were used to construct the score: cytogenetics, FLT3-internal tandem duplication, length of relapse-free interval and previous allo-SCT. Using this stratification system, three groups were defined: favourable (26% of patients), intermediate (29%) and poor-risk (45%), with an expected 5-year OS of 52%, 26% and 7%, respectively. The SALFLAGE score discriminated a subset of patients with an acceptable long-term outcome using FLAG-Ida/FLAGO-Ida regimen. The results of this retrospective analysis should be validated in independent external cohorts. PMID:27118319

  11. Social and ecological factors influencing offspring survival in wild macaques

    PubMed Central

    Kerhoas, Daphne; Perwitasari-Farajallah, Dyah; Agil, Muhammad; Widdig, Anja

    2014-01-01

    Premature loss of offspring decreases direct fitness of parents. In gregarious mammals, both ecological and social variables impact offspring survival and may interact with each other in this regard. Although a number of studies have investigated factors influencing offspring loss in mammals, we still know very little on how different factors interact with one another. We therefore investigated fetal and infant mortality in 3 large groups of wild crested macaques (Macaca nigra) over a period of up to 5 years by including potential social causes such as maternal dominance rank, male immigration, between group encounters, and ecological conditions such as rainfall in a multivariate survival analysis using Cox proportional hazards model. Infant but not fetal survival was most impaired after a recent takeover of the alpha-male position by an immigrant male. Furthermore, infant survival probability increased when there was an increase in number of group adult females and rainfall. Fetal survival probability also increased with an increase of these 2 factors, but more in high-ranking than low-ranking females. Fetal survival, unlike that of infants, was also improved by an increase of intergroup encounter rates. Our study thus stresses the importance of survival analyses using a multivariate approach and encompassing more than a single offspring stage to investigate the determinants of female direct fitness. We further provide evidence for fitness costs and benefits of group living, possibly deriving from high pressures of both within- and between-group competition, in a wild primate population. PMID:25214754

  12. Survival of mountain quail translocated from two distinct source populations

    USGS Publications Warehouse

    Troy, Ronald J.; Coates, Peter S.; Connelly, John W.; Gillette, Gifford; Delehanty, David J.

    2013-01-01

    Translocation of mountain quail (Oreortyx pictus) to restore viable populations to their former range has become a common practice. Because differences in post-release vital rates between animals from multiple source populations has not been well studied, wildlife and land managers may arbitrarily choose the source population or base the source population on immediate availability when planning translocation projects. Similarly, an understanding of the optimal proportion of individuals from different age and sex classes for translocation would benefit translocation planning. During 2006 and 2007, we captured and translocated 125 mountain quail from 2 ecologically distinct areas: 38 from southern California and 87 from southwestern Oregon. We released mountain quail in the Bennett Hills of south-central Idaho. We radio-marked and monitored a subsample of 58 quail and used them for a 2-part survival analysis. Cumulative survival probability was 0.23 ± 0.05 (SE) at 150 days post-release. We first examined an a priori hypothesis (model) that survival varied between the 2 distinct source populations. We found that source population did not explain variation in survival. This result suggests that wildlife managers have flexibility in selecting source populations for mountain quail translocation efforts. In a post hoc examination, we pooled the quail across source populations and evaluated differences in survival probabilities between sex and age classes. The most parsimonious model indicated that adult male survival was substantially less than survival rates of other mountain quail age and sex classes (i.e., interaction between sex and age). This result suggests that translocation success could benefit by translocating yearling males rather than adult males, perhaps because adult male breeding behavior results in vulnerability to predators

  13. Factors affecting breeding season survival of Red-Headed Woodpeckers in South Carolina.

    SciTech Connect

    Kilgo, John, C.; Vukovich, Mark

    2011-11-18

    Red-headed woodpecker (Melanerpes erythrocephalus) populations have declined in the United States and Canada over the past 40 years. However, few demographic studies have been published on the species and none have addressed adult survival. During 2006-2007, we estimated survival probabilities of 80 radio-tagged red-headed woodpeckers during the breeding season in mature loblolly pine (Pinus taeda) forests in South Carolina. We used known-fate models in Program MARK to estimate survival within and between years and to evaluate the effects of foliar cover (number of available cover patches), snag density treatment (high density vs. low density), and sex and age of woodpeckers. Weekly survival probabilities followed a quadratic time trend, being lowest during mid-summer, which coincided with the late nestling and fledgling period. Avian predation, particularly by Cooper's (Accipiter cooperii) and sharp-shinned hawks (A. striatus), accounted for 85% of all mortalities. Our best-supported model estimated an 18-week breeding season survival probability of 0.72 (95% CI = 0.54-0.85) and indicated that the number of cover patches interacted with sex of woodpeckers to affect survival; females with few available cover patches had a lower probability of survival than either males or females with more cover patches. At the median number of cover patches available (n = 6), breeding season survival of females was 0.82 (95% CI = 0.54-0.94) and of males was 0.60 (95% CI = 0.42-0.76). The number of cover patches available to woodpeckers appeared in all 3 of our top models predicting weekly survival, providing further evidence that woodpecker survival was positively associated with availability of cover. Woodpecker survival was not associated with snag density. Our results suggest that protection of {ge}0.7 cover patches per ha during vegetation control activities in mature pine forests will benefit survival of this Partners In Flight Watch List species.

  14. Assessing survival in a multi-population system: a case study on bat populations.

    PubMed

    Papadatou, Eleni; Ibáñez, Carlos; Pradel, Roger; Juste, Javier; Gimenez, Olivier

    2011-04-01

    In long-lived animals, adult survival is among the most important determinants of population dynamics. Although it may show considerable variation both in time and among populations and sites, a single survival estimate per species is often used in comparative evolutionary studies or in conservation management to identify threatened populations. We estimated adult survival of the isabelline serotine bat Eptesicus isabellinus using capture-recapture data collected on six maternity colonies scattered over a large area (distance 8-103 km) during periods varying from 8 to 26 years. We modelled temporal and inter-colony variations as random effects in a Bayesian framework and estimated mean annual adult survival of females on two scales and a single survival value across all colonies. On a coarse scale, we grouped colonies according to two different habitat types and investigated the effect on survival. A difference in adult survival was detected between the two habitat types [posterior mean of annual survival probability 0.71; 95% credible interval (CI) 0.51-0.86 vs. 0.60; 0.28-0.89], but it was not statistically supported. On a fine scale, survival of the six colonies ranged between 0.58 (95% CI 0.23-0.92) and 0.81 (0.73-0.88), with variation between only two colonies being statistically supported. Overall survival was 0.72 (95% CI 0.57-0.93) with important inter-colony variability (on a logit scale 0.98; 95% CI 0.00-8.16). Survival varied temporally in a random fashion across colonies. Our results show that inference based solely on single colonies should be treated with caution and that a representative unbiased estimate of survival for any species should ideally be based on multiple populations. PMID:20852896

  15. Survival on antiretroviral treatment among adult HIV-infected patients in Nepal: a retrospective cohort study in far-western Region, 2006–2011

    PubMed Central

    2013-01-01

    Background Though financial and policy level efforts are made to expand antiretroviral treatment (ART) service free of cost, survival outcome of ART program has not been systematically evaluated in Nepal. This study assesses the mortality rates and determinants among adult HIV-infected patients on ART in Far-western region of Nepal. Methods This retrospective cohort study included 1024 (51.2% men) HIV-infected patients aged ≥15 years, who started ART between May 15th 2006 and May 15th 2011 in five ART sites in the Far-western region, Nepal. Follow-up time was calculated from the date of ART initiation to date of death or censoring (loss to follow-up, transferred out, or 15 November 2011). Mortality rates (per 100 person-years) were calculated. Kaplan-Meier and Cox-regression models were used to estimate survival and explore determinants of mortality. Results The median follow-up time was 19.1 months. The crude mortality rate was 6.3 (95% confidence interval (CI) 5.3-7.6) but more than three-times higher in first 3 months after ART initiation (21.9 (95% CI 16.6- 28.8)). About 12% (83% men) of those newly initiated on ART died during follow-up. The independent determinants of mortality were male sex (hazard ratio (HR) 4.55, 95% CI 2.43-8.51), poor baseline performance scale (bedridden <50% of the day during the past month, HR 2.05, 95% CI 1.19-3.52; bedridden >50% of the day during the past month, HR 3.41, 95% CI 1.67-6.98 compared to normal activity), one standard deviation decrease in baseline bodyweight (HR 1.04, 95% CI 1.01-1.07), and poor WHO clinical stage (stage III, HR 2.96, 95% CI 1.31-6.69; stage IV, HR 3.28, 95% CI 1.30-8.29 compared to WHO clinical stage I or II). Conclusions High mortality was observed within the first 3 months of ART initiation. Patients with poor baseline clinical characteristics had higher mortality, especially men. Earlier initiation of ART through expanded testing and counselling should be encouraged in HIV-infected patients. PMID

  16. The effects of body size and climate on post-weaning survival of elephant seals at Heard Island

    USGS Publications Warehouse

    McMahon, Clive R; New, Leslie; Fairley, E.J.; Hindell, M.A.; Burton, H.R.

    2015-01-01

    The population size of southern elephant seals in the southern Indian and Pacific Oceans decreased precipitously between the 1950s and 1990s. To investigate the reasons behind this, we studied the population of southern elephant seals at Heard Island between 1949 and 1954, using data collected by the early Australian National Antarctic Research Expeditions. Seals were marked and measured (lengths) as weaned pups, and resighted at Heard and Marion islands and in the Vestfold Hills, Antarctica in subsequent years. Bayesian state-space mark-recapture models were used to determine post-weaning survival. Yearling survival was consistently lower (ϕy: 0.28–0.40) than sub-adult survival (ϕs: 0.79–0.83). We found evidence for constant sub-adult survival and time-dependent resight probabilities. Weaning length was an important determinate of yearling survival, with the probability of survival increasing with individual length. There was some suggestion that the Southern Annular Mode influenced yearling survival but this evidence was not strong. Nonetheless, our results provide further support showing that size at independence affects yearling survival. Given the known sensitivity of southern elephant seal populations to survival early in life, it is possible that the decline in population size at Heard Island between the 1950s and 1990s like that at Macquarie Island was due to low yearling survival mediated through maternal ability to produce large pups and the dominant environmental conditions mothers experience during pregnancy.

  17. Probability 1/e

    ERIC Educational Resources Information Center

    Koo, Reginald; Jones, Martin L.

    2011-01-01

    Quite a number of interesting problems in probability feature an event with probability equal to 1/e. This article discusses three such problems and attempts to explain why this probability occurs with such frequency.

  18. Clinical signs, pathology and dose-dependent survival of adult wood frogs, Rana sylvatica, inoculated orally with frog virus 3 Ranavirus sp., Iridoviridae.

    PubMed

    Forzn, Mara J; Jones, Kathleen M; Vanderstichel, Raphal V; Wood, John; Kibenge, Frederick S B; Kuiken, Thijs; Wirth, Wytamma; Ariel, Ellen; Daoust, Pierre-Yves

    2015-05-01

    Amphibian populations suffer massive mortalities from infection with frog virus 3 FV3, genus Ranavirus, family Iridoviridae, a pathogen also involved in mortalities of fish and reptiles. Experimental oral infection with FV3 in captive-raised adult wood frogs, Rana sylvatica Lithobates sylvaticus, was performed as the first step in establishing a native North American animal model of ranaviral disease to study pathogenesis and host response. Oral dosing was successful LD50 was 10(2.93 2.423.44) p.f.u. for frogs averaging 35mm in length. Onset of clinical signs occurred 614days post-infection p.i. median 11 days p.i. and time to death was 1014 days p.i. median 12 days p.i.. Each tenfold increase in virus dose increased the odds of dying by 23-fold and accelerated onset of clinical signs and death by approximately 15. Ranavirus DNA was demonstrated in skin and liver of all frogs that died or were euthanized because of severe clinical signs. Shedding of virus occurred in faeces 710 days p.i. 34.5days before death and skin sheds 10 days p.i. 01.5days before death of some frogs dead from infection. Most common lesions were dermal erosion and haemorrhages haematopoietic necrosis in bone marrow, kidney, spleen and liver and necrosis in renal glomeruli, tongue, gastrointestinal tract and urinary bladder mucosa. Presence of ranavirus in lesions was confirmed by immunohistochemistry. Intracytoplasmic inclusion bodies probably viral were present in the bone marrow and the epithelia of the oral cavity, gastrointestinal tract, renal tubules and urinary bladder. Our work describes a ranaviruswood frog model and provides estimates that can be incorporated into ranavirus disease ecology models. PMID:25593158

  19. Review and hypothesis: syndromes with severe intrauterine growth restriction and very short stature--are they related to the epigenetic mechanism(s) of fetal survival involved in the developmental origins of adult health and disease?

    PubMed

    Hall, Judith G

    2010-02-01

    Diagnosing the specific type of severe intrauterine growth restriction (IUGR) that also has post-birth growth restriction is often difficult. Eight relatively common syndromes are discussed identifying their unique distinguishing features, overlapping features, and those features common to all eight syndromes. Many of these signs take a few years to develop and the lifetime natural history of the disorders has not yet been completely clarified. The theory behind developmental origins of adult health and disease suggests that there are mammalian epigenetic fetal survival mechanisms that downregulate fetal growth, both in order for the fetus to survive until birth and to prepare it for a restricted extra-uterine environment, and that these mechanisms have long lasting effects on the adult health of the individual. Silver-Russell syndrome phenotype has recently been recognized to be related to imprinting/methylation defects. Perhaps all eight syndromes, including those with single gene mutation origin, involve the mammalian mechanism(s) of fetal survival downsizing. Insights into those mechanisms should provide avenues to understanding the natural history, the heterogeneity and possible therapy not only for these eight syndromes, but for the common adult diseases with which IUGR is associated. PMID:20101705

  20. Natal location influences movement and survival of a spatially structured population of snail kites.

    PubMed

    Martin, Julien; Kitchens, Wiley M; Hines, James E

    2007-08-01

    Despite the accepted importance of the need to better understand how natal location affects movement decisions and survival of animals, robust estimates of movement and survival in relation to the natal location are lacking. Our study focuses on movement and survival related to the natal location of snail kites in Florida and shows that kites, in addition to exhibiting a high level of site tenacity to breeding regions, also exhibit particular attraction to their natal region. More specifically, we found that estimates of movement from post-dispersal regions were greater toward natal regions than toward non-natal regions (differences were significant for three of four regions). We also found that estimates of natal philopatry were greater than estimates of philopatry to non-natal regions (differences were statistically significant for two of four regions). A previous study indicated an effect of natal region on juvenile survival; in this study, we show an effect of natal region on adult survival. Estimates of adult survival varied among kites that were hatched in different regions. Adults experienced mortality rates characteristic of the region occupied at the time when survival was measured, but because there is a greater probability that kites will return to their natal region than to any other regions, their survival was ultimately influenced by their natal region. In most years, kites hatched in southern regions had greater survival probabilities than did kites hatched in northern regions. However, during a multiregional drought, one of the northern regions served as a refuge from drought, and during this perturbation, survival was greater for birds hatched in the north. Our study shows that natal location may be important in influencing the ecological dynamics of kites but also highlights the importance of considering temporal variation in habitat conditions of spatially structured systems when attempting to evaluate the conservation value of habitats. PMID

  1. Natal location influences movement and survival of a spatially structured population of snail kites

    USGS Publications Warehouse

    Martin, J.; Kitchens, W.M.; Hines, J.E.

    2007-01-01

    Despite the accepted importance of the need to better understand how natal location affects movement decisions and survival of animals, robust estimates of movement and survival in relation to the natal location are lacking. Our study focuses on movement and survival related to the natal location of snail kites in Florida and shows that kites, in addition to exhibiting a high level of site tenacity to breeding regions, also exhibit particular attraction to their natal region. More specifically, we found that estimates of movement from post-dispersal regions were greater toward natal regions than toward non-natal regions (differences were significant for three of four regions). We also found that estimates of natal philopatry were greater than estimates of philopatry to non-natal regions (differences were statistically significant for two of four regions). A previous study indicated an effect of natal region on juvenile survival; in this study, we show an effect of natal region on adult survival. Estimates of adult survival varied among kites that were hatched in different regions. Adults experienced mortality rates characteristic of the region occupied at the time when survival was measured, but because there is a greater probability that kites will return to their natal region than to any other regions, their survival was ultimately influenced by their natal region. In most years, kites hatched in southern regions had greater survival probabilities than did kites hatched in northern regions. However, during a multiregional drought, one of the northern regions served as a refuge from drought, and during this perturbation, survival was greater for birds hatched in the north. Our study shows that natal location may be important in influencing the ecological dynamics of kites but also highlights the importance of considering temporal variation in habitat conditions of spatially structured systems when attempting to evaluate the conservation value of habitats.

  2. On Probability Domains III

    NASA Astrophysics Data System (ADS)

    Frič, Roman; Papčo, Martin

    2015-12-01

    Domains of generalized probability have been introduced in order to provide a general construction of random events, observables and states. It is based on the notion of a cogenerator and the properties of product. We continue our previous study and show how some other quantum structures fit our categorical approach. We discuss how various epireflections implicitly used in the classical probability theory are related to the transition to fuzzy probability theory and describe the latter probability theory as a genuine categorical extension of the former. We show that the IF-probability can be studied via the fuzzy probability theory. We outline a "tensor modification" of the fuzzy probability theory.

  3. Annual recapture and survival rates of two non-breeding adult populations of Roseate Terns Stema dougallii captured on the Great Barrier Reef, Australia, and estimates of their population sizes

    USGS Publications Warehouse

    O'Neill, P.; Minton, C.D.T.; Nisbet, I.C.T.; Hines, J.E.

    2008-01-01

    Capture-recapture data from two disparate breeding populations of Roseate Terns (Sterna dougallii) captured together as non-breeding individuals from 2002 to 2007 in the southern Great Barrier Reef. Australia were analyzed for both survival rate and recapture rate. The average annual survival rate for the birds from the Asian population (S. d. bangsi) (0.901) is higher than that of the other population of unknown breeding origin (0.819). There was large variability in survival in both populations among years, but the average survival rate of 0.85 is similar to estimates for the same species in North America. The Cormack-Jolly-Seber models used in program MARK to estimate survival rates also produced estimated of recapture probabilities and population sizes. These estimates of population size were 29,000 for S. D. bangsi and 8,300 for the study area and much larger than the documented numbers in the likely breeding areas, suggesting that many breeding sites are currently unknown.

  4. Glutamate Increases In Vitro Survival and Proliferation and Attenuates Oxidative Stress-Induced Cell Death in Adult Spinal Cord-Derived Neural Stem/Progenitor Cells via Non-NMDA Ionotropic Glutamate Receptors.

    PubMed

    Hachem, Laureen D; Mothe, Andrea J; Tator, Charles H

    2016-08-15

    Traumatic spinal cord injury (SCI) leads to a cascade of secondary chemical insults, including oxidative stress and glutamate excitotoxicity, which damage host neurons and glia. Transplantation of exogenous neural stem/progenitor cells (NSPCs) has shown promise in enhancing regeneration after SCI, although survival of transplanted cells remains poor. Understanding the response of NSPCs to the chemical mediators of secondary injury is essential in finding therapies to enhance survival. We examined the in vitro effects of glutamate and glutamate receptor agonists on adult rat spinal cord-derived NSPCs. NSPCs isolated from the periventricular region of the adult rat spinal cord were exposed to various concentrations of glutamate for 96 h. We found that glutamate treatment (500 μM) for 96 h significantly increased live cell numbers, reduced cell death, and increased proliferation, but did not significantly alter cell phenotype. Concurrent glutamate treatment (500 μM) in the setting of H2O2 exposure (500 μM) for 10 h increased NSPC survival compared to H2O2 exposure alone. The effects of glutamate on NSPCs were blocked by the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)/kainate receptor antagonist GYKI-52466, but not by the N-methyl-D-aspartic acid receptor antagonist MK-801 or DL-AP5, or the mGluR3 antagonist LY-341495. Furthermore, treatment of NSPCs with AMPA, kainic acid, or the kainate receptor-specific agonist (RS)-2-amino-3-(3-hydroxy-5-tert-butylisoxazol-4-yl)propanoic acid mimicked the responses seen with glutamate both alone and in the setting of oxidative stress. These findings offer important insights into potential mechanisms to enhance NSPC survival and implicate a potential role for glutamate in promoting NSPC survival and proliferation after traumatic SCI. PMID:27316370

  5. Probability and Relative Frequency

    NASA Astrophysics Data System (ADS)

    Drieschner, Michael

    2016-01-01

    The concept of probability seems to have been inexplicable since its invention in the seventeenth century. In its use in science, probability is closely related with relative frequency. So the task seems to be interpreting that relation. In this paper, we start with predicted relative frequency and show that its structure is the same as that of probability. I propose to call that the `prediction interpretation' of probability. The consequences of that definition are discussed. The "ladder"-structure of the probability calculus is analyzed. The expectation of the relative frequency is shown to be equal to the predicted relative frequency. Probability is shown to be the most general empirically testable prediction.

  6. Evolution and Probability.

    ERIC Educational Resources Information Center

    Bailey, David H.

    2000-01-01

    Some of the most impressive-sounding criticisms of the conventional theory of biological evolution involve probability. Presents a few examples of how probability should and should not be used in discussing evolution. (ASK)

  7. BIODEGRADATION PROBABILITY PROGRAM (BIODEG)

    EPA Science Inventory

    The Biodegradation Probability Program (BIODEG) calculates the probability that a chemical under aerobic conditions with mixed cultures of microorganisms will biodegrade rapidly or slowly. It uses fragment constants developed using multiple linear and non-linear regressions and d...

  8. Probability on a Budget.

    ERIC Educational Resources Information Center

    Ewbank, William A.; Ginther, John L.

    2002-01-01

    Describes how to use common dice numbered 1-6 for simple mathematical situations including probability. Presents a lesson using regular dice and specially marked dice to explore some of the concepts of probability. (KHR)

  9. Adult Congenital Heart Association

    MedlinePlus

    ... survivable, manageable, yet in the routine years between infancy and adulthood, sometimes forgettable. The Adult Congenital Heart ... understand the continuum of the disease from its infancy. The Adult Congential Heart Association brings together valuable ...

  10. Dependent Probability Spaces

    ERIC Educational Resources Information Center

    Edwards, William F.; Shiflett, Ray C.; Shultz, Harris

    2008-01-01

    The mathematical model used to describe independence between two events in probability has a non-intuitive consequence called dependent spaces. The paper begins with a very brief history of the development of probability, then defines dependent spaces, and reviews what is known about finite spaces with uniform probability. The study of finite…

  11. Searching with probabilities

    SciTech Connect

    Palay, A.J.

    1985-01-01

    This book examines how probability distributions can be used as a knowledge representation technique. It presents a mechanism that can be used to guide a selective search algorithm to solve a variety of tactical chess problems. Topics covered include probabilities and searching the B algorithm and chess probabilities - in practice, examples, results, and future work.

  12. In All Probability, Probability is not All

    ERIC Educational Resources Information Center

    Helman, Danny

    2004-01-01

    The national lottery is often portrayed as a game of pure chance with no room for strategy. This misperception seems to stem from the application of probability instead of expectancy considerations, and can be utilized to introduce the statistical concept of expectation.

  13. Estimating survival of neotropical-nearctic migratory birds: Are they dead or just dispersed?

    USGS Publications Warehouse

    Marshall, M.R.; Wilson, R.R.; Cooper, R.J.

    2000-01-01

    The most common method for estimating adult survival in site specific demographic studies of Neotropical-Nearctic migratory bird populations is by measuring the return rate of marked individuals. Return rate historically has been defined as the ratio of resighted birds to the total number banded (i.e., with bands on) the prior year, and has been used as a 'minimum number known alive' estimate of survival. Return rates potentially underestimate true survival (the complement of mortality) for two reasons. First, not every bird that returns to the study plot is actually encountered by the field researcher, and second, not every bird that survives to the next breeding season returns to the study plot. We use a branching-tree diagram to illustrate that the essential problem with return rate methodology is that the fate of birds that are not resighted is unknown. It is widely recognized that Cormack-Jolly-Seber based analyses greatly improve 'survival' estimates by incorporating the probability of resighting a bird given that it is alive and present on the study plot. However, these estimates will underestimate true survival if birds disperse beyond the range of the resighting effort. Because long-distance dispersal events are an important component of migratory bird ecology, we cannot estimate true survival from return rate data until better information on dispersal distances and probabilities are collected. We discuss several conservation implications of underestimating survival,.and suggest terminology that is potentially less confusing.

  14. Estimating Survival and Recruitment in a Freshwater Mussel Population Using Mark-recapture Techniques

    USGS Publications Warehouse

    Villella, R.F.; Smith, D.R.; Lemarie, D.P.

    2004-01-01

    We used a mark-recapture method and model averaging to estimate apparent survival, recruitment and rate of population growth in a native freshwater mussel population at a site on the Cacapon River, which is a tributary to the Potomac River. Over 2200 Elliptio complanata, E. fisheriana and Lampsilis cariosa were uniquely tagged over a period of 4 y. Recapture probabilities were higher in spring and summer than in winter except for L. cariosa which had a low probability of recapture regardless of time of year. All three species had high annual adult survival rates (>90%) with lower estimated survival of small (???55 mm) mussels (43%-69%). The variation in apparent survival over time was similar for all three species. This suggests that whatever environmental variables affect survival of mussels in this site affected all three species the same. Recruitment rates were low (1-4%) for both E. complanata and L. cariosa, with E. fisheriana having several periods of high (15-23%) recruitment. Distribution within the site was affected by both downstream and upstream movement, though movement rates were generally <1%. Average population growth rates for E. complanata (?? = 0.996, SE = 0.053), L. cariosa (?? = 0.993, SE = 0.076) and E. fisheriana (?? = 1.084, SE = 0.276) indicated static populations. Population growth rate approximating 1.0 suggests this site supports a stable freshwater mussel population through a life history strategy of low but constant recruitment and high annual adult survival.

  15. Systemic Insecticides Reduce Feeding, Survival and Fecundity of Adult Black Vine Weevils (Coleoptera: Curculionidae) on a Variety of Ornamental Nursery Crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A series of bioassays were conducted to test the systemic activity of clothianidin, chlorantraniliprole, dinotefuran, and thiamethoxam against adult black vine weevils (Otiorhynchus sulcatus F.) on Taxus, Heuchera, Astilbe, Sedum, Euonymus, and Rhododendron grown in containers. The insecticides wer...

  16. Activation of PI3K/mTOR pathway occurs in most adult low-grade gliomas and predicts patient survival.

    PubMed

    McBride, Sean M; Perez, Daniel A; Polley, Mei-Yin; Vandenberg, Scott R; Smith, Justin S; Zheng, Shichun; Lamborn, Kathleen R; Wiencke, John K; Chang, Susan M; Prados, Michael D; Berger, Mitchel S; Stokoe, David; Haas-Kogan, Daphne A

    2010-03-01

    Recent evidence suggests the Akt-mTOR pathway may play a role in development of low-grade gliomas (LGG). We sought to evaluate whether activation of this pathway correlates with survival in LGG by examining expression patterns of proteins within this pathway. Forty-five LGG tumor specimens from newly diagnosed patients were analyzed for methylation of the putative 5'-promoter region of PTEN using methylation-specific PCR as well as phosphorylation of S6 and PRAS40 and expression of PTEN protein using immunohistochemistry. Relationships between molecular markers and overall survival (OS) were assessed using Kaplan-Meier methods and exact log-rank test. Correlation between molecular markers was determined using the Mann-Whitney U and Spearman Rank Correlation tests. Eight of the 26 patients with methylated PTEN died, as compared to 1 of 19 without methylation. There was a trend towards statistical significance, with PTEN methylated patients having decreased survival (P = 0.128). Eight of 29 patients that expressed phospho-S6 died, whereas all 9 patients lacking p-S6 expression were alive at last follow-up. There was an inverse relationship between expression of phospho-S6 and survival (P = 0.029). There was a trend towards decreased survival in patients expressing phospho-PRAS40 (P = 0.077). Analyses of relationships between molecular markers demonstrated a statistically significant positive correlation between expression of p-S6(235) and p-PRAS40 (P = 0.04); expression of p-S6(240) correlated positively with PTEN methylation (P = 0.04) and negatively with PTEN expression (P = 0.03). Survival of LGG patients correlates with phosphorylation of S6 protein. This relationship supports the use of selective mTOR inhibitors in the treatment of low grade glioma. PMID:19705067

  17. A Posteriori Transit Probabilities

    NASA Astrophysics Data System (ADS)

    Stevens, Daniel J.; Gaudi, B. Scott

    2013-08-01

    Given the radial velocity (RV) detection of an unseen companion, it is often of interest to estimate the probability that the companion also transits the primary star. Typically, one assumes a uniform distribution for the cosine of the inclination angle i of the companion's orbit. This yields the familiar estimate for the prior transit probability of ~Rlowast/a, given the primary radius Rlowast and orbital semimajor axis a, and assuming small companions and a circular orbit. However, the posterior transit probability depends not only on the prior probability distribution of i but also on the prior probability distribution of the companion mass Mc, given a measurement of the product of the two (the minimum mass Mc sin i) from an RV signal. In general, the posterior can be larger or smaller than the prior transit probability. We derive analytic expressions for the posterior transit probability assuming a power-law form for the distribution of true masses, dΓ/dMcvpropMcα, for integer values -3 <= α <= 3. We show that for low transit probabilities, these probabilities reduce to a constant multiplicative factor fα of the corresponding prior transit probability, where fα in general depends on α and an assumed upper limit on the true mass. The prior and posterior probabilities are equal for α = -1. The posterior transit probability is ~1.5 times larger than the prior for α = -3 and is ~4/π times larger for α = -2, but is less than the prior for α>=0, and can be arbitrarily small for α > 1. We also calculate the posterior transit probability in different mass regimes for two physically-motivated mass distributions of companions around Sun-like stars. We find that for Jupiter-mass planets, the posterior transit probability is roughly equal to the prior probability, whereas the posterior is likely higher for Super-Earths and Neptunes (10 M⊕ - 30 M⊕) and Super-Jupiters (3 MJup - 10 MJup), owing to the predicted steep rise in the mass function toward smaller

  18. Demographics and 2008 Run Timing of Adult Lost River (Deltistes luxatus) and Shortnose (Chasmistes brevirostris) Suckers in Upper Klamath Lake

    USGS Publications Warehouse

    Janney, Eric C.; Hayes, Brian S.; Hewitt, David A.; Barry, Patrick M.; Scott, Alta; Koller, Justin; Johnson, Mark; Blackwood, Greta

    2009-01-01

    We used capture-recapture data to assess population dynamics of endangered Lost River suckers (Deltistes luxatus) and shortnose suckers (Chasmistes brevirostris) in Upper Klamath Lake, Oregon. The Cormack-Jolly-Seber method was used to estimate apparent survival probabilities, and a temporal symmetry model was used to estimate annual seniority probabilities. Information theoretic modeling was used to assess variation in parameter estimates due to time, gender, and species. In addition, length data were used to detect multiple year-class failures and events of high recruitment into adult spawning populations. Survival of adult Lost River and shortnose suckers varied substantially across years. Relatively high annual mortality was observed for the lakeshore-spawning Lost River sucker subpopulation in 2002 and for the river spawning subpopulation in 2001. Shortnose suckers experienced high mortality in 2001 and 2004. This indicates that high mortality events are not only species specific, but also are specific to subpopulations for Lost River suckers. Seniority probability estimates and length composition data indicate that recruitment of new individuals into adult sucker populations has been sparse. The overall fitness of Upper Klamath Lake sucker populations are of concern given the low observed survival in some years and the paucity of recent recruitment. During most years, estimates of survival probabilities were lower than seniority probabilities, indicating net losses in adult sucker population abundances. The evidence for decline was more marked for shortnose suckers than for Lost River suckers. Our data indicated that sucker survival for both species, but especially shortnose suckers, was sometimes low in years without any observed fish kills. This indicates that high mortality can occur over a protracted period, resulting in poor annual survival, but will not necessarily be observed in association with a fish kill. A better understanding of the factors

  19. High temperature effects on water loss and survival examining the hardiness of female adults of the spider beetles, Mezium affine and Gibbium aequinoctiale.

    PubMed

    Yoder, Jay A; Chambers, Michael J; Tank, Justin L; Keeney, George D

    2009-01-01

    A remarkable ability to tolerate temperatures as high as 52 degrees C for Mezium affine Boieldieu and 56 degrees C for Gibbium aequinoctiale Boieldieu (Coleoptera: Anobiidae) was discovered as part of a water balance study that was conducted to determine whether desiccation-resistance (xerophilic water balance classification) is linked to survival at high temperature. Characteristics of the heat shock response were an intermediate, reversible level of injury, appearing as though dead; greater recovery from heat shock by G. aequinoctiale (57%) than M. affine (30%) that supplemented higher temperature survival by G. aequinoctiale; and lack of protection generated by conditioning at sublethal temperature. Heatinduced mortality is attributed to an abrupt, accelerated water loss at 50 degrees C for M. affine and 54 degrees C for G. aequinoctiale, not to the species (M. affine) that loses water the slowest and has the lower activation energy, E(a) as a measure of cuticular boundary effectiveness. These temperatures where water loss increases sharply are not critical transition temperatures because Arrhenius analysis causes them to be erased (uninterrupted Boltzmann function) and E(a) fails to change when cuticular lipid from these beetles is removed. Our conclusion is that the temperature thresholds for survival and accelerated water loss closely match, and the key survival element in hot and dry environments contributing to wide distribution of G. aequinoctiale and M. affine derives from rising temperature prompting entry into quiescence and a resistance in cuticular lipid fluidity. PMID:20053123

  20. Higher Early Monocyte and Total Lymphocyte Counts Are Associated with Better Overall Survival after Standard Total Body Irradiation, Cyclophosphamide, and Fludarabine Reduced-Intensity Conditioning Double Umbilical Cord Blood Allogeneic Stem Cell Transplantation in Adults.

    PubMed

    Le Bourgeois, Amandine; Peterlin, Pierre; Guillaume, Thierry; Delaunay, Jacques; Duquesne, Alix; Le Gouill, Steven; Moreau, Philippe; Mohty, Mohamad; Campion, Loïc; Chevallier, Patrice

    2016-08-01

    This single-center retrospective study aimed to report the impact of early hematopoietic and immune recoveries after a standard total body irradiation, cyclophosphamide, and fludarabine (TCF) reduced-intensity conditioning (RIC) regimen for double umbilical cord blood (dUCB) allogeneic stem cell transplantation (allo-SCT) in adults. We analyzed 47 consecutive patients older than 17 years who engrafted after a dUCB TCF allo-SCT performed between January 2006 and April 2013 in our department. Median times for neutrophil and platelet recoveries were 17 (range, 6 to 59) and 37 days (range, 0 to 164), respectively. The 3-year overall (OS) and disease-free survivals, relapse incidence, and nonrelapse mortality were 65.7%, 57.2%, 27.1%, and 19%, respectively. In multivariate analysis, higher day +30 monocyte (≥615/mm(3); hazard ratio [HR], .04; 95% confidence interval [CI], .004 to .36; P < .01) and day +42 lymphocyte (≥395/mm(3); HR, .16; 95% CI, .03 to .78; P = .02) counts were independently associated with better OS. These results suggest that early higher hematopoietic and immune recovery is predictive of survival after dUCB TCF RIC allo-SCT in adults. Factors other than granulocyte colony-stimulating factor, which was used in all cases, favoring expansion of monocytes or lymphocytes, should be tested in the future as part of the UCB transplantation procedure. PMID:27118570

  1. Good Ol' Boys, Mean Girls, and Tyrants: A Phenomenological Study of the Lived Experiences and Survival Strategies of Bullied Women Adult Educators

    ERIC Educational Resources Information Center

    Sedivy-Benton, Amy; Strohschen, Gabriele; Cavazos, Nora; Boden-McGill, Carrie

    2015-01-01

    Bullying in higher education is an increasingly common phenomenon that negatively affects organizational climate, completed work's quality and quantity, and students' educational experiences. The purpose of this phenomenological study was to investigate the lived experiences of women adult educators who were targets of bullying. Six…

  2. Survival of adult Tamarixia radiata subjected to different short-term storage methods prior to field releases for biological control of Asian citrus psyllid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tamarixia radiata is regarded as one of the Asian citrus psyllid’s most important natural enemies and is thus currently being mass-reared and released by a number of laboratories in North America. It may not always be possible to immediately release newly-emerged adults, in which case it would be a...

  3. Mortality by education level at late-adult ages in Turin: a survival analysis using frailty models with period and cohort approaches

    PubMed Central

    Zarulli, Virginia; Marinacci, Chiara; Costa, Giuseppe; Caselli, Graziella

    2013-01-01

    Objectives Neglecting the presence of unobserved heterogeneity in survival analysis models has been showed to potentially lead to underestimating the effect of the covariates included in the analysis. This study aimed to investigate the role of unobserved heterogeneity of frailty on the estimation of mortality differentials from age 50 on by education level. Design Longitudinal mortality follow-up of the census-based Turin population linked with the city registry office. Setting Italian North-Western city of Turin, observation window 1971–2007. Population 391 170 men and 456 216 women followed from age 50. Primary outcome measures Mortality rate ratios obtained from survival analysis regression. Models were estimated with and without the component of unobserved heterogeneity of frailty and controlling for mortality improvement over time from both cohort and period perspectives. Results In the majority of cases, the models without frailty estimated a smaller educational gradient than the models with frailty. Conclusions The results draw the attention of the potential underestimation of the mortality inequalities by socioeconomic levels in survival analysis models when not controlling for unobserved heterogeneity of frailty. PMID:23824314

  4. Single-case probabilities

    NASA Astrophysics Data System (ADS)

    Miller, David

    1991-12-01

    The propensity interpretation of probability, bred by Popper in 1957 (K. R. Popper, in Observation and Interpretation in the Philosophy of Physics, S. Körner, ed. (Butterworth, London, 1957, and Dover, New York, 1962), p. 65; reprinted in Popper Selections, D. W. Miller, ed. (Princeton University Press, Princeton, 1985), p. 199) from pure frequency stock, is the only extant objectivist account that provides any proper understanding of single-case probabilities as well as of probabilities in ensembles and in the long run. In Sec. 1 of this paper I recall salient points of the frequency interpretations of von Mises and of Popper himself, and in Sec. 2 I filter out from Popper's numerous expositions of the propensity interpretation its most interesting and fertile strain. I then go on to assess it. First I defend it, in Sec. 3, against recent criticisms (P. Humphreys, Philos. Rev. 94, 557 (1985); P. Milne, Erkenntnis 25, 129 (1986)) to the effect that conditional [or relative] probabilities, unlike absolute probabilities, can only rarely be made sense of as propensities. I then challenge its predominance, in Sec. 4, by outlining a rival theory: an irreproachably objectivist theory of probability, fully applicable to the single case, that interprets physical probabilities as instantaneous frequencies.

  5. Allogeneic hematopoietic stem cell transplantation could improve survival of cytogenetically normal adult acute myeloid leukemia patients with DNMT3A mutations.

    PubMed

    Xu, Yang; Sun, Yanjun; Shen, Hongjie; Ding, Lin; Yang, Zhen; Qiu, Huiying; Sun, Aining; Chen, Suning; Wu, Depei

    2015-11-01

    DNMT3A mutations are frequent in cytogenetically normal acute myeloid leukemia (cn-AML) patients and associated with poor survival. The role of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in DNMT3A(mut) cn-AML patients remains unclear. In this study, we retrospectively analyzed the prognostic impact of DNMT3A mutations and explored the role of allo-HSCT in 308 cn-AML patients who received consolidation of intensive chemotherapy or allo-HSCT in our center from March 2005 to May 2014. In the whole cohort, 63 patients (20.5%) were identified with DNMT3A exon 23 mutations and R882H was the most frequent variant. DNMT3A(mut) patients had shorter overall survival (3-year OS: 31.9% vs. 52.0%, P = 0.009) and disease-free survival (3-year DFS: 21.8% vs. 40.1%, P = 0.004) compared with DNMT3A(wt) patients. Based on FLT3/NPM1/CEBPA mutations, 308 cn-AML patients were divided into favorable/intermediate group (n = 262) and unfavorable group (n = 46). There were no significant differences in 3-year OS and 3-year DFS between DNMT3A(mut) and DNMT3A(wt) patients in both favorable/intermediate and unfavorable groups. Additionally, in multivariate analysis, DNMT3A mutation remained an independent adverse prognostic factor for the survival. In the DNMT3A(mut) cohort, 23 complete remission (CR) patients received allo-HSCT consolidation and 32 CR patients received chemotherapy consolidation, dramatic differences were observed in 3-year OS (51.7% vs. 28.9%, P = 0.048) and 3-year DFS (41.6% vs. 14.9%, P = 0.024) between allo-HSCT group and chemotherapy group. Collectively, DNMT3A mutation is a poor prognostic factor for cn-AML patients and allo-HSCT could improve survival of cn-AML patients with DNMT3A mutations. PMID:26223865

  6. Design and Analysis of Salmonid Tagging Studies in the Columbia Basin, Volume XV; Appraisal of the Relationship between Tag Detection Efficiency at Bonneville Dam and the Precision of In-River Survival Estimates of Returning PIT-Tagged Chinook Salmon, 2000 Technical Report.

    SciTech Connect

    Perez-Comas, Joes A.; Skalski, John R.

    2000-07-01

    In the advent of the installation of a PIT-tag interrogation system in the Cascades Island fish ladder at Bonneville Dam, this report provides guidance on the anticipated precision of in-river survival estimates for returning adult salmonids, between Bonneville and Lower Granite dams, for various levels of system-wide adult detection probability at Bonneville Dam. Precision was characterized by the standard error of the survival estimates and the coefficient of variation of the survival estimates. The anticipated precision of in-river survival estimates for returning adult salmonids was directly proportional to the number of PIT-tagged smolts released and to the system-wide adult detection efficiency at Bonneville Dam, as well as to the in-river juvenile survival above Lower Granite Dam. Moreover, for a given release size and system-wide adult detection efficiency at Bonneville Dam, higher estuarine and marine survival rates also produced more precise survival estimates. With a system-wide detection probability of P{sub BA} = 1 at Bonneville Dam, the anticipated CVs for in-river survival estimate ranged between 9.4 and 20% with release sizes of 10,000 smolts. Moreover, if the system-wide adult detection efficiency at Bonneville Dam is less than maximum (i.e., P{sub BA} < 1), precision of CV {le} 20% could still be attained. For example, for releases of 10,000 PIT-tagged fish a CV of 20% in the estimates of in-river survival for returning adult salmon could be reach with system-wide detection probabilities of 0.2 {le} P{sub BA} {le} 0.6, depending on the tagging scenario.

  7. Probability with Roulette

    ERIC Educational Resources Information Center

    Marshall, Jennings B.

    2007-01-01

    This article describes how roulette can be used to teach basic concepts of probability. Various bets are used to illustrate the computation of expected value. A betting system shows variations in patterns that often appear in random events.

  8. Launch Collision Probability

    NASA Technical Reports Server (NTRS)

    Bollenbacher, Gary; Guptill, James D.

    1999-01-01

    This report analyzes the probability of a launch vehicle colliding with one of the nearly 10,000 tracked objects orbiting the Earth, given that an object on a near-collision course with the launch vehicle has been identified. Knowledge of the probability of collision throughout the launch window can be used to avoid launching at times when the probability of collision is unacceptably high. The analysis in this report assumes that the positions of the orbiting objects and the launch vehicle can be predicted as a function of time and therefore that any tracked object which comes close to the launch vehicle can be identified. The analysis further assumes that the position uncertainty of the launch vehicle and the approaching space object can be described with position covariance matrices. With these and some additional simplifying assumptions, a closed-form solution is developed using two approaches. The solution shows that the probability of collision is a function of position uncertainties, the size of the two potentially colliding objects, and the nominal separation distance at the point of closest approach. ne impact of the simplifying assumptions on the accuracy of the final result is assessed and the application of the results to the Cassini mission, launched in October 1997, is described. Other factors that affect the probability of collision are also discussed. Finally, the report offers alternative approaches that can be used to evaluate the probability of collision.

  9. Age-specificity of black-capped chickadee survival rates: Analysis of capture-recapture data

    USGS Publications Warehouse

    Loery, G.; Pollock, K.H.; Nichols, J.D.; Hines, J.E.

    1987-01-01

    The ornithological literature indicates a widespread belief in two generalizations about the age-specificity of avian survival rates: (1) survival rates of young birds for some period following fledging are lower than those of adults, and (2) after reaching adulthood survival rates are constant for birds of all ages. There is a growing body of evidence in support of the first generalization, although little is known about how long the survival difference between young and adults lasts. This latter question can be addressed with capture-recapture or band recovery studies based on birds marked in the winter, but the inability to determine age in many species during winter has prevented the use of standard methods. There is very little evidence supporting the second generalization, and we are in need of methods and actual analyses that address this question. In the present paper we restate the two generalizations as hypotheses and test them using data from a wintering Black-capped Chickadee (Parus atricapillus) population in Connecticut, which has been studied by Loery for 26 yr. We use a cohort-based Jolly-Seber approach, which should be useful in other investigations of this nature. We found strong evidence of lower survival rates in 1st-yr birds than in adults, but could not determine whether this was the result of higher mortality rates, higher emigration rates, or a combination of the two. We also found evidence that survival rates of adult birds were not constant with age but decreased at a rate of ? 3.5%/yr. As adult birds are very faithful to their wintering areas, we believe that almost all this decrease can be attributed to an increase in mortality with age. Simulation results suggest that heterogeneity of capture probabilities could not explain the magnitude of the decrease in survival with age. Age-dependent tag loss is also discussed as an alternative explanation, but is dismissed as very unlikely in this situation. This analysis thus provides some of the

  10. Detection and apparent survival of PIT-tagged stream fish in winter.

    PubMed

    Weber, Christine; Scheuber, Hannes; Nilsson, Christer; Alfredsen, Knut T

    2016-04-01

    Environmental fluctuations exert strong control on behavior, survival, and fitness of stream biota. Technical improvements increasingly allow for tracking the response of large numbers of individuals to environmental fluctuations, for instance, by remote detection of animals equipped with PIT (passive integrated transponder) tags. PIT tags were implanted into 393 juvenile and adult brown trout Salmo trutta L. and European sculpin Cottus gobio L. in a boreal stream subjected to considerable ice formation. With weekly trackings over 6 months, we quantified apparent survival and detection probability in relation to biological, environmental, and methodological factors. Individuals with a higher physical condition in autumn showed a higher apparent survival; this pattern was consistent across all species and age classes. Detection probability decreased with increasing thickness of the surface ice layer; this effect was most pronounced for juvenile trout and benthic-living sculpin, both tagged with smaller-sized tags. Detection probability was reduced in structurally complex habitats. Our study demonstrates that apparent survival and particularly detection probability may show pronounced spatiotemporal variation. In order to compare results from different sampling occasions and sites, a good knowledge of the study site and of the regulating factors is crucial. PMID:27066238

  11. Habitat fragmentation effects on annual survival of the federally protected eastern indigo snake

    USGS Publications Warehouse

    Breininger, D.R.; Mazerolle, M.J.; Bolt, M.R.; Legare, M.L.; Drese, J.H.; Hines, J.E.

    2012-01-01

    The eastern indigo snake (Drymarchon couperi) is a federally listed species, most recently threatened by habitat loss and habitat degradation. In an effort to estimate snake survival, a total of 103 individuals (59 males, 44 females) were followed using radio-tracking from January 1998 to March 2004 in three landscape types that had increasing levels of habitat fragmentation: (1) conservation cores; (2) conservation areas along highways; (3) suburbs. Because of a large number of radio-tracking locations underground for which the state of snakes (i.e. alive or dead) could not be assessed, we employed a multistate approach to model snake apparent survival and encounter probability of live and dead snakes. We predicted that male snakes in suburbs would have the lowest annual survival. We found a transmitter implantation effect on snake encounter probability, as snakes implanted on a given occasion had a lower encounter probability on the next visit compared with snakes not implanted on the previous occasion. Our results indicated that adult eastern indigo snakes have relatively high survival in conservation core areas, but greatly reduced survival in conservation areas along highways and in suburbs. These findings indicate that habitat fragmentation is likely to be the critical factor for species' persistence.

  12. Prognostic and survival analysis of presbyopia: The healthy twin study

    NASA Astrophysics Data System (ADS)

    Lira, Adiyani; Sung, Joohon

    2015-12-01

    Presbyopia, a vision condition in which the eye loses its flexibility to focus on near objects, is part of ageing process which mostly perceptible in the early or mid 40s. It is well known that age is its major risk factor, while sex, alcohol, poor nutrition, ocular and systemic diseases are known as common risk factors. However, many other variables might influence the prognosis. Therefore in this paper we developed a prognostic model to estimate survival from presbyopia. 1645 participants which part of the Healthy Twin Study, a prospective cohort study that has recruited Korean adult twins and their family members based on a nation-wide registry at public health agencies since 2005, were collected and analyzed by univariate analysis as well as Cox proportional hazard model to reveal the prognostic factors for presbyopia while survival curves were calculated by Kaplan-Meier method. Besides age, sex, diabetes, and myopia; the proposed model shows that education level (especially engineering program) also contribute to the occurrence of presbyopia as well. Generally, at 47 years old, the chance of getting presbyopia becomes higher with the survival probability is less than 50%. Furthermore, our study shows that by stratifying the survival curve, MZ has shorter survival with average onset time about 45.8 compare to DZ and siblings with 47.5 years old. By providing factors that have more effects and mainly associate with presbyopia, we expect that we could help to design an intervention to control or delay its onset time.

  13. Experimental Probability in Elementary School

    ERIC Educational Resources Information Center

    Andrew, Lane

    2009-01-01

    Concepts in probability can be more readily understood if students are first exposed to probability via experiment. Performing probability experiments encourages students to develop understandings of probability grounded in real events, as opposed to merely computing answers based on formulae.

  14. Statistical Survival Analysis of Fish and Wildlife Tagging Studies; SURPH.1 Manual - Analysis of Release-Recapture Data for Survival Studies, 1994 Technical Manual.

    SciTech Connect

    Smith, Steven G.; Skalski, John R.; Schelechte, J. Warren

    1994-12-01

    Program SURPH is the culmination of several years of research to develop a comprehensive computer program to analyze survival studies of fish and wildlife populations. Development of this software was motivated by the advent of the PIT-tag (Passive Integrated Transponder) technology that permits the detection of salmonid smolt as they pass through hydroelectric facilities on the Snake and Columbia Rivers in the Pacific Northwest. Repeated detections of individually tagged smolt and analysis of their capture-histories permits estimates of downriver survival probabilities. Eventual installation of detection facilities at adult fish ladders will also permit estimation of ocean survival and upstream survival of returning salmon using the statistical methods incorporated in SURPH.1. However, the utility of SURPH.1 far exceeds solely the analysis of salmonid tagging studies. Release-recapture and radiotelemetry studies from a wide range of terrestrial and aquatic species have been analyzed using SURPH.1 to estimate discrete time survival probabilities and investigate survival relationships. The interactive computing environment of SURPH.1 was specifically developed to allow researchers to investigate the relationship between survival and capture processes and environmental, experimental and individual-based covariates. Program SURPH.1 represents a significant advancement in the ability of ecologists to investigate the interplay between morphologic, genetic, environmental and anthropogenic factors on the survival of wild species. It is hoped that this better understanding of risk factors affecting survival will lead to greater appreciation of the intricacies of nature and to improvements in the management of wild resources. This technical report is an introduction to SURPH.1 and provides a user guide for both the UNIX and MS-Windows{reg_sign} applications of the SURPH software.

  15. Acceptance, values, and probability.

    PubMed

    Steel, Daniel

    2015-10-01

    This essay makes a case for regarding personal probabilities used in Bayesian analyses of confirmation as objects of acceptance and rejection. That in turn entails that personal probabilities are subject to the argument from inductive risk, which aims to show non-epistemic values can legitimately influence scientific decisions about which hypotheses to accept. In a Bayesian context, the argument from inductive risk suggests that value judgments can influence decisions about which probability models to accept for likelihoods and priors. As a consequence, if the argument from inductive risk is sound, then non-epistemic values can affect not only the level of evidence deemed necessary to accept a hypothesis but also degrees of confirmation themselves. PMID:26386533

  16. Effect of Hepatitis C Positivity on Survival in Adult Patients Undergoing Heart Transplantation (from the United Network for Organ Sharing Database).

    PubMed

    Kumar, Sachin; Deo, Salil V; Altarabsheh, Salah E; Dunlay, Shannon M; Sarabu, Nagaraju; Sareyyupoglu, Basar; Elgudin, Yakov; Medalion, Benjamin; ElAmm, Chantal; Ginwalla, Mahazarin; Zacharias, Michael; Benatti, Rodolpho; Oliveira, Guilherme H; Kilic, Ahmet; Fonarow, Gregg C; Park, Soon J

    2016-07-01

    Concerns exist regarding orthotropic heart transplantation in hepatitis C virus (HCV) seropositive recipients. Thus, a national registry was accessed to evaluate early and late outcome in HCV seropositive recipients undergoing heart transplant. Retrospective analysis of the United Network for Organ Sharing registry (1991 to 2014) was performed to evaluate recipient profile and clinical outcome of patients with HCV seropositive (HCV +ve) and seronegative (HCV -ve). Adjusted results of early mortality and late survival were compared between cohorts. From 23,507 patients (mean age 52 years; 75% men), 481 (2%) were HCV +ve (mean age 52 years; 77% men). Annual proportion of HCV +ve recipients was comparable over the study period (range 1.3% to 2.7%; p = 0.2). The HCV +ve cohort had more African-American (22% vs 17%; p = 0.01), previous left ventricular assist device utilization (21% vs 14%; p <0.01) and more hepatitis B core Ag+ve recipients (17% vs 5%; p <0.01). However, both cohorts were comparable in terms of extracorporeal membrane oxygenator usage (p = 0.7), inotropic support (p = 0.2), intraaortic balloon pump (p = 0.7) support, serum creatinine (p = 0.7), and serum bilirubin (p = 0.7). Proportion of status 1A patients was similar (24% HCV + vs 21% HCV -); however, wait time for HCV +ve recipients were longer (mean 23 vs 19 days; p <0.01). Among donor variables, age (p = 0.8), hepatitis B status (p = 0.4), and Center for Diseases Control high-risk status (p = 0.9) were comparable in both cohorts. At a median follow-up of 4 years, 67% patients were alive, 28% died, and 1.1% were retransplanted (3.4% missing). Overall survival was worse in the HCV+ cohort (64.3% vs 72.9% and 43.2% vs 55% at 5 and 10 years; p <0.01), respectively. Late renal (odds ratio [OR] 1.2 [1 to 1.6]; p = 0.02) and liver dysfunction (odds ratio 4.5 [1.2 to 15.7]; p = 0.01) occurs more frequently in HCV +ve recipients. On adjusted analysis, HCV seropositivity is

  17. Critical role of astrocytic interleukin-17 A in post-stroke survival and neuronal differentiation of neural precursor cells in adult mice.

    PubMed

    Lin, Y; Zhang, J-C; Yao, C-Y; Wu, Y; Abdelgawad, A F; Yao, S-L; Yuan, S-Y

    2016-01-01

    The brain and the immune system interact in complex ways after ischemic stroke, and the long-term effects of immune response associated with stroke remain controversial. As a linkage between innate and adaptive immunity, interleukin-17 A (IL-17 A) secreted from gamma delta (γδ) T cells has detrimental roles in the pathogenesis of acute ischemic stroke. However, to date, the long-term actions of IL-17 A after stroke have not been investigated. Here, we found that IL-17 A showed two distinct peaks of expression in the ischemic hemisphere: the first occurring within 3 days and the second on day 28 after stroke. Our data also showed that astrocyte was the major cellular source of IL-17 A that maintained and augmented subventricular zone (SVZ) neural precursor cells (NPCs) survival, neuronal differentiation, and subsequent synaptogenesis and functional recovery after stroke. IL-17 A also promoted neuronal differentiation in cultured NPCs from the ischemic SVZ. Furthermore, our in vitro data revealed that in primary astrocyte cultures activated astrocytes released IL-17 A via p38 mitogen-activated protein kinase (MAPK). Culture media from reactive astrocytes increased neuronal differentiation of NSCs in vitro. Blockade of IL-17 A with neutralizing antibody prevented this effect. In addition, after screening for multiple signaling pathways, we revealed that the p38 MAPK/calpain 1 signaling pathway was involved in IL-17 A-mediated neurogenesis in vivo and in vitro. Thus, our results reveal a previously uncharacterized property of astrocytic IL-17 A in the maintenance and augment of survival and neuronal differentiation of NPCs, and subsequent synaptogenesis and spontaneous recovery after ischemic stroke. PMID:27336717

  18. Age-dependent survival of island vs. mainland populations of two avian scavengers: delving into migration costs.

    PubMed

    Sanz-Aguilar, Ana; De Pablo, Félix; Donázar, José Antonio

    2015-10-01

    Large terrestrial long-lived birds (including raptors) are typically sedentary on islands, even when they are migratory on the mainland. Density-dependent variation in the age at first breeding has been described as responsible for the long-term persistence of long-lived bird populations on islands. However, sedentary island populations may also benefit from higher survival rates derived from the absence of migration costs, especially for young individuals. Thus, sedentary island populations can mimic a natural experiment to study migration costs. We estimated the age-dependent survival of two sedentary raptors on the island of Menorca (Egyptian vultures Neophron percnopterus and red kites Milvus milvus) and compared these estimates with those reported for other migratory and sedentary populations. In Menorca, Egyptian vultures, but not red kites, showed low levels of human-related mortality resulting in extremely high survival probabilities, probably due to different diet choices and behavioral patterns. Juvenile Egyptian vultures and red kites in the studied population had lower survival probabilities than adults. This difference, however, was smaller than those reported for mainland migrant populations, which showed a lower juvenile survival rate. In fact, between-population comparisons suggested that survival of the young in migrant populations may be triggered by mortality factors in wintering areas. In contrast, adult survival may respond to mortality factors in breeding areas. Our results suggest that raptor species that become sedentary on islands may benefit from higher pre-breeder survival prospects in comparison with their mainland migrant counterparts. This fact, in combination with an earlier age at first reproduction, may facilitate their persistence. PMID:26013875

  19. Carbonaceous Survivability on Impact

    NASA Technical Reports Server (NTRS)

    Bunch, T. E.; Becker, Luann; Morrison, David (Technical Monitor)

    1994-01-01

    In order to gain knowledge about the potential contributions of comets and cosmic dust to the origin of life on Earth, we need to explore the survivability of their potential organic compounds on impact and the formation of secondary products that may have arisen from the chaotic events sustained by the carriers as they fell to Earth. We have performed a series of hypervelocity impact experiments using carbon-bearing impactors (diamond, graphite, kerogens, PAH crystals, and Murchison and Nogoya meteorites) into Al plate targets at velocities - 6 km/s. Estimated peak shock pressures probably did not exceed 120 GPa and peak shock temperatures were probably less than 4000 K for times of nano- to microsecs. Nominal crater dia. are less than one mm. The most significant results of these experiments are the preservation of the higher mass PAHs (e. g., pyrene relative to napthalene) and the formation of additional alkylated PAHs. We have also examined the residues of polystyrene projectiles impacted by a microparticle accelerator into targets at velocities up to 15 km/s. This talk will discuss the results of these experiments and their implications with respect to the survival of carbonaceous deliverables to early Earth. The prospects of survivability of organic molecules on "intact" capture of cosmic dust in space via soft: and hard cosmic dust collectors will also be discussed.

  20. Population size, survival, and movements of white-cheeked pintails in Eastern Puerto Rico

    USGS Publications Warehouse

    Collazo, J.A.; Bonilla-Martinez, G.

    2001-01-01

    We estimated numbers and survival of White-cheeked Pintails (Anas bahamensis) in eastern Puerto Rico during 1996-1999. We also quantified their movements between Culebra Island and the Humacao Wildlife Refuge, Puerto Rico. Mark-resight population size estimates averaged 1020 pintails during nine, 3-month sampling periods from January 1997 to June 1999. On average, minimum regional counts were 38 % lower than mark-resight estimates (mean = 631). Adult survival was 0.51 ?? 0.09 (SE). This estimate is similar for other anatids of similar size but broader geographic distribution. The probability of pintails surviving and staying in Humacao was hiher (67 %) than for counterparts on Culebra (31 %). The probability of surviving and moving from Culebra to Humacao (41 %) was higher than from Humacao to Culebra (20 %). These findings, and available information on reproduction, indicate that the Humacao Wildlife Refuge refuge has an important role in the regional demography of pintails. Our findings on population numbers and regional survival are encouraging, given concerns about the species' status due to habitat loss and hunting. However, our outlook for the species is tempered by the remaining gaps in the population dynamics of pintails; for examples, survival estimates of broods and fledglings (age 0-1) are needed for a comprehensive status assessment. Until additional data are obtianed, White-cheeked Pintails should continue to be protectd from hunting in Puerto Rico.

  1. Effects of radio marking on prairie falcons: Attachment failures provide insights about survival

    USGS Publications Warehouse

    Steenhof, Karen; Bates, Kirk K.; Fuller, Mark R.; Kochert, Michael N.; McKinley, J.O.; Lukacs, Paul M.

    2006-01-01

    From 1999-2002, we attached satellite-received platform transmitter terminals (PTTs) to 40 adult female prairie falcons (Falco mexicanus) on their nesting grounds in the Snake River Birds of Prey National Conservation Area (NCA) in southwest Idaho. We used 3 variations of a backpack harness design that had been used previously on raptors. Each radiomarked falcon also received a color leg band with a unique alphanumeric code. We monitored survival of birds using radiotelemetry and searched for marked birds on their nesting grounds during breeding seasons after marking. Because 6 falcons removed their harnesses during the first year, we were able to compare survival rates of birds that shed PTTs with those that retained them. We describe a harness design that failed prematurely as well as designs that proved successful for long-term PTT attachment. We resighted 21 marked individuals on nesting areas 1-5 years after they were radiomarked and documented 13 mortalities of satellite-tracked falcons. We used a Cormack-Jolly-Seber model to estimate apparent survival probability based on band resighting and telemetry data. Platform transmitter terminals had no short-term effects on falcons or their nesting success during the nesting season they were marked, but birds that shed their transmitters increased their probability of survival. Estimated annual survival for birds that shed their transmitters was 87% compared to 49% for birds wearing transmitters. We discuss possible reasons for differences in apparent survival rates and offer recommendations for future marking of falcons.

  2. Annual survival and site fidelity of Steller's eiders molting along the Alaska Peninsula

    USGS Publications Warehouse

    Flint, P.L.; Petersen, M.R.; Dau, C.P.; Hines, J.E.; Nichols, J.D.

    2000-01-01

    Populations of Steller's eiders (Polysticta stelleri) molting and wintering along the Alaska Peninsula have declined since the 1960's. We captured and marked a large sample of Steller's eiders molting in 2 lagoons along the Alaska Peninsula between 1975-97. We used mark-recapture analysis techniques to estimate annual survival and movement probabilities within and among lagoons for male and female eiders. Estimates of annual survival (??SE) were 0.899 ?? 0.032 for females and 0.765 ?? 0.044 for males. Both sexes showed high rates of fidelity to specific molting locations (>95%) within lagoons; yet we found no evidence that annual probability of survival differed among groups molting in different locations either within or among lagoons. We found weak evidence that annual survival decreased between the periods 1975-81 and 1991-97. The lower survival of males compared to females is unusual for waterfowl and may result in a female-biased sex ratio. We conclude that a decrease in adult survival may have initiated the long-term population decline. Further, a shortage of males may be limiting reproductive potential.

  3. Annual survival and site fidelity of Stellar's Eiders molting along the Alaska Peninsula

    USGS Publications Warehouse

    Flint, P.L.; Petersen, M.R.; Dau, C.P.; Hines, J.E.; Nichols, J.D.

    2000-01-01

    Populations of Steller?s eiders (Polysticta stelleri) molting and wintering along the Alaska Peninsula have declined since the 1960's. We captured and marked a large sample of Steller's eiders molting in 2 lagoons along the Alaska Peninsula between 1975-97. We used mark-recapture analysis techniques to estimate annual survival and movement probabilities within and among lagoons for male and female eiders. Estimates of annual survival (?SE) were 0.899 ? 0.032 for females and 0.765 ? 0.044 for males. Both sexes showed high rates of fidelity to specific molting locations (>95%) within lagoons; yet we found no evidence that annual probability of survival differed among groups molting in different locations either within or among lagoons. We found weak evidence that annual survival decreased between the periods 1975-81 and 1991-97. The lower survival of males compared to females is unusual for waterfowl and may result in a female-biased sex ratio. We conclude that a decrease in adult survival may have initiated the long-term population decline. Further, a shortage of males may be limiting reproductive potential.

  4. Low temperature survival in different life stages of the Iberian slug, Arion lusitanicus.

    PubMed

    Slotsbo, Stine; Hansen, Lars Monrad; Holmstrup, Martin

    2011-02-01

    The slug Arion lusitanicus Mabille (Gastropoda: Pulmonata: Arionidae) is an invasive species which has spread to most parts of Europe. The area of origin is unknown, but A. lusitanicus seems to cope well with the local conditions in the countries to which it has migrated. It spreads rapidly, occurs often in high densities and has become a serious pest in most European countries. Therefore there is an urgent need for better knowledge of the ecophysiology of A. lusitanicus, such as the influence of climatic conditions, in order to develop prognostic models and strategies for novel pest management practises. The aim of our study was to investigate the influence of subzero temperatures in relation to winter survival. A. lusitanicus is shown to be freeze-tolerant in some life stages. Most juveniles and some adult slugs survived being frozen at -1.3°C for 3days, but none of the slugs survived freezing at -3°C. The eggs survived subzero temperatures (down to -2°C) probably by supercooling. Juveniles and adults may also survive in a supercooled state (down to -3°C) but are generally poor supercoolers. Therefore, the winter survival of A. lusitanicus depends to a high degree on migration to habitats protected from low winter temperatures, e.g. under plant litter, buried in the soil or in compost heaps. PMID:21168402

  5. Problems in estimating age-specific survival rates from recovery data of birds ringed as young

    USGS Publications Warehouse

    Anderson, D.R.; Burnham, Kenneth P.; White, Gary C.

    1985-01-01

    (1) The life table model is frequently employed in the analysis of ringer samples of young in bird populations. The basic model is biologically unrealistic and of little use in making inferences concerning age-specific survival probabilities. (2) This model rests on a number of restrictive assumptions, the failure of which causes serious biases. Several important assumptions are not met with real data and the estimators of age-specific survival are not robust enough to these failures. (3) Five major problems in the use of the life table method are reviewed. Examples are provided to illustrate several of the problems involved in using this method in making inferences about survival rates and its age-specific nature. (4) We conclude that this is an invalid procedure and it should not be used. Furthermore, ringing studies involving only young birds are pointless as regards survival estimation because no valid method exists for estimating age-specific or time-specific survival rates from such data. (5) In our view, inferences about age-specific survival rates are possible only if both young and adult (or young, subadult and adult) age classes are ringed each year for k years (k ≥ 2).

  6. Approximating Integrals Using Probability

    ERIC Educational Resources Information Center

    Maruszewski, Richard F., Jr.; Caudle, Kyle A.

    2005-01-01

    As part of a discussion on Monte Carlo methods, which outlines how to use probability expectations to approximate the value of a definite integral. The purpose of this paper is to elaborate on this technique and then to show several examples using visual basic as a programming tool. It is an interesting method because it combines two branches of…

  7. Varga: On Probability.

    ERIC Educational Resources Information Center

    Varga, Tamas

    This booklet resulted from a 1980 visit by the author, a Hungarian mathematics educator, to the Teachers' Center Project at Southern Illinois University at Edwardsville. Included are activities and problems that make probablility concepts accessible to young children. The topics considered are: two probability games; choosing two beads; matching…

  8. Application of Quantum Probability

    NASA Astrophysics Data System (ADS)

    Bohdalová, Mária; Kalina, Martin; Nánásiová, Ol'ga

    2009-03-01

    This is the first attempt to smooth time series using estimators with applying quantum probability with causality (non-commutative s-maps on an othomodular lattice). In this context it means that we use non-symmetric covariance matrix to construction of our estimator.

  9. Univariate Probability Distributions

    ERIC Educational Resources Information Center

    Leemis, Lawrence M.; Luckett, Daniel J.; Powell, Austin G.; Vermeer, Peter E.

    2012-01-01

    We describe a web-based interactive graphic that can be used as a resource in introductory classes in mathematical statistics. This interactive graphic presents 76 common univariate distributions and gives details on (a) various features of the distribution such as the functional form of the probability density function and cumulative distribution…

  10. Surviving Cancer

    MedlinePlus

    ... Watch the video to learn more about these breast cancer survivors. To enlarge the video, click the brackets in the lower right-hand corner. To reduce the video, press the Escape (Esc) button on your keyboard.) Age and Health May Affect Survival A person's age, and more importantly his or ...

  11. Beyond Survival

    ERIC Educational Resources Information Center

    Steffenson, Dave

    1975-01-01

    The author argues that environmentalists need to realize that the present ecological crisis is essentially a value crisis, not merely a fight for survival alone. He envisions a complete value change for the human population and advocates the incorporation of value strategies into all environmental education programs immediately. (MA)

  12. ENDOCRINE DISRUPTIVE ACTIONS OF INHALED BENZO(a)PYRENE ON OVARIAN FUNCTION AND FETAL SURVIVAL IN FISHER F-344 ADULT RATS

    PubMed Central

    Archibong, Anthony E.; Ramesh, Aramandla; Inyang, Frank; Niaz, Mohammad S.; Hood, Darryl B.; Kopsombut, Prapaporn

    2012-01-01

    This study evaluated the effect of inhaled BaP on female reproductive function. Rats were exposed to 50, or 75 or 100 μg BaP/m3, four hours a day for 14 days via inhalation. Plasma E2, P4, LH and FSH concentrations were determined. Ovarian BaP metabolism and aryl hydrocarbon hydrolase (AHH) activity at proestrus were determined and fertility evaluations were conducted. Ovulation rate and number of pups/litter were reduced in rats exposed to 100 μg BaP/m3 compared with other treatment and control groups. Plasma concentrations of E2, and LH were significantly reduced at proestrus in BaP-exposed versus those of controls whereas those of P4 were significantly reduced at diestrus I. The activity of AHH in ovarian and liver tissues and concentrations of BaP 7,8-diol and BaP 3,6-dione metabolites increased in an exposure concentration-dependent manner. These data suggest that exposure of rats to BaP prior to mating contributes to reduced ovarian function and fetal survival. PMID:23059060

  13. Think Fast, Feel Fine, Live Long: A 29-Year Study of Cognition, Health, and Survival in Middle-Aged and Older Adults.

    PubMed

    Aichele, Stephen; Rabbitt, Patrick; Ghisletta, Paolo

    2016-04-01

    In a 29-year study of 6,203 individuals ranging in age from 41 to 96 years at initial assessment, we evaluated the relative and combined influence of 65 mortality risk factors, which included sociodemographic variables, lifestyle attributes, medical indices, and multiple cognitive abilities. Reductions in mortality risk were most associated with higher self-rated health, female gender, fewer years as a smoker, and smaller decrements in processing speed with age. Thus, two psychological variables-subjective health status and processing speed-were among the top predictors of survival. We suggest that these psychological attributes, unlike risk factors that are more narrowly defined, reflect (and are influenced by) a broad range of health-related behaviors and characteristics. Information about these attributes can be obtained with relatively little effort or cost and-given the tractability of these measures in different cultural contexts-may prove expedient for prevention, diagnosis, and treatment of conditions related to increased mortality risk in diverse human populations. PMID:26917212

  14. Endocrine disruptive actions of inhaled benzo(a)pyrene on ovarian function and fetal survival in fisher F-344 adult rats.

    PubMed

    Archibong, Anthony E; Ramesh, Aramandla; Inyang, Frank; Niaz, Mohammad S; Hood, Darryl B; Kopsombut, Prapaporn

    2012-12-01

    This study evaluated the effect of inhaled BaP on female reproductive function. Rats were exposed to 50, or 75 or 100 μg BaP/m(3), 4 h a day for 14 days via inhalation. Plasma E(2), P(4), LH and FSH concentrations were determined. Ovarian BaP metabolism and aryl hydrocarbon hydrolase (AHH) activity at proestrus were determined and fertility evaluations were conducted. Ovulation rate and number of pups/litter were reduced in rats exposed to 100 μg BaP/m(3) compared with other treatment and control groups. Plasma concentrations of E(2), and LH were significantly reduced at proestrus in BaP-exposed versus those of controls whereas those of P(4) were significantly reduced at diestrus I. The activity of AHH in ovarian and liver tissues and concentrations of BaP 7,8-diol and BaP 3,6-dione metabolites increased in an exposure concentration-dependent manner. These data suggest that exposure of rats to BaP prior to mating contributes to reduced ovarian function and fetal survival. PMID:23059060

  15. Doubly robust survival trees.

    PubMed

    Steingrimsson, Jon Arni; Diao, Liqun; Molinaro, Annette M; Strawderman, Robert L

    2016-09-10

    Estimating a patient's mortality risk is important in making treatment decisions. Survival trees are a useful tool and employ recursive partitioning to separate patients into different risk groups. Existing 'loss based' recursive partitioning procedures that would be used in the absence of censoring have previously been extended to the setting of right censored outcomes using inverse probability censoring weighted estimators of loss functions. In this paper, we propose new 'doubly robust' extensions of these loss estimators motivated by semiparametric efficiency theory for missing data that better utilize available data. Simulations and a data analysis demonstrate strong performance of the doubly robust survival trees compared with previously used methods. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27037609

  16. Linking habitat selection and predation risk to spatial variation in survival

    PubMed Central

    DeCesare, Nicholas J; Hebblewhite, Mark; Bradley, Mark; Hervieux, David; Neufeld, Lalenia; Musiani, Marco; Mysterud, Atle

    2014-01-01

    1. A central assumption underlying the study of habitat selection is that selected habitats confer enhanced fitness. Unfortunately, this assumption is rarely tested, and in some systems, gradients of predation risk may more accurately characterize spatial variation in vital rates than gradients described by habitat selection studies. 2. Here, we separately measured spatial patterns of both resource selection and predation risk and tested their relationships with a key demographic trait, adult female survival, for a threatened ungulate, woodland caribou (Rangifer tarandus caribou Gmelin). We also evaluated whether exposure to gradients in both predation risk and resource selection value was manifested temporally through instantaneous or seasonal effects on survival outcomes. 3. We used Cox proportional hazards spatial survival modelling to assess the relative support for 5 selection- and risk-based definitions of habitat quality, as quantified by woodland caribou adult female survival. These hypotheses included scenarios in which selection ideally mirrored survival, risk entirely drove survival, non-ideal selection correlated with survival but with additive risk effects, an ecological trap with maladaptive selection and a non-spatial effect of annual variation in weather. 4. Indeed, we found positive relationships between the predicted values of a resource selection function (RSF) and survival, yet subsequently incorporating an additional negative effect of predation risk greatly improved models further. This revealed a positive, but non-ideal relationship between selection and survival. Gradients in these covariates were also shown to affect individual survival probability at multiple temporal scales. Exposure to increased predation risk had a relatively instantaneous effect on survival outcomes, whereas variation in habitat suitability predicted by an RSF had both instantaneous and longer-term seasonal effects on survival. 5. Predation risk was an additive source

  17. Soil-applied imidacloprid translocates to ornamental flowers and reduces survival of adult Coleomegilla maculata, Harmonia axyridis, and Hippodamia convergens lady beetles, and larval Danaus plexippus and Vanessa cardui butterflies.

    PubMed

    Krischik, Vera; Rogers, Mary; Gupta, Garima; Varshney, Aruna

    2015-01-01

    Integrated Pest Management (IPM) is a decision making process used to manage pests that relies on many tactics, including cultural and biological control, which are practices that conserve beneficial insects and mites, and when needed, the use of conventional insecticides. However, systemic, soil-applied neonicotinoid insecticides are translocated to pollen and nectar of flowers, often for months, and may reduce survival of flower-feeding beneficial insects. Imidacloprid seed-treated crops (0.05 mg AI (active ingredient) /canola seed and 1.2 mg AI/corn seed) translocate less than 10 ppb to pollen and nectar. However, higher rates of soil-applied imidacloprid are used in nurseries and urban landscapes, such as 300 mg AI/10 L (3 gallon) pot and 69 g AI applied to the soil under a 61 (24 in) cm diam. tree. Translocation of imidacloprid from soil (300 mg AI) to flowers of Asclepias curassavica resulted in 6,030 ppb in 1X and 10,400 ppb in 2X treatments, which are similar to imidacloprid residues found in another plant species we studied. A second imidacloprid soil application 7 months later resulted in 21,000 ppb in 1X and 45,000 ppb in 2X treatments. Consequently, greenhouse/nursery use of imidacloprid applied to flowering plants can result in 793 to 1,368 times higher concentration compared to an imidacloprid seed treatment (7.6 ppb pollen in seed- treated canola), where most research has focused. These higher imidacloprid levels caused significant mortality in both 1X and 2X treatments in 3 lady beetle species, Coleomegilla maculata, Harmonia axyridis, and Hippodamia convergens, but not a fourth species, Coccinella septempunctata. Adult survival were not reduced for monarch, Danaus plexippus and painted lady, Vanessa cardui, butterflies, but larval survival was significantly reduced. The use of the neonicotinoid imidacloprid at greenhouse/nursery rates reduced survival of beneficial insects feeding on pollen and nectar and is incompatible with the principles of IPM

  18. Soil-Applied Imidacloprid Translocates to Ornamental Flowers and Reduces Survival of Adult Coleomegilla maculata, Harmonia axyridis, and Hippodamia convergens Lady Beetles, and Larval Danaus plexippus and Vanessa cardui Butterflies

    PubMed Central

    Krischik, Vera; Rogers, Mary; Gupta, Garima; Varshney, Aruna

    2015-01-01

    Integrated Pest Management (IPM) is a decision making process used to manage pests that relies on many tactics, including cultural and biological control, which are practices that conserve beneficial insects and mites, and when needed, the use of conventional insecticides. However, systemic, soil-applied neonicotinoid insecticides are translocated to pollen and nectar of flowers, often for months, and may reduce survival of flower-feeding beneficial insects. Imidacloprid seed-treated crops (0.05 mg AI (active ingredient) /canola seed and 1.2 mg AI/corn seed) translocate less than 10 ppb to pollen and nectar. However, higher rates of soil-applied imidacloprid are used in nurseries and urban landscapes, such as 300 mg AI/10 L (3 gallon) pot and 69 g AI applied to the soil under a 61 (24 in) cm diam. tree. Translocation of imidacloprid from soil (300 mg AI) to flowers of Asclepias curassavica resulted in 6,030 ppb in 1X and 10,400 ppb in 2X treatments, which are similar to imidacloprid residues found in another plant species we studied. A second imidacloprid soil application 7 months later resulted in 21,000 ppb in 1X and 45,000 ppb in 2X treatments. Consequently, greenhouse/nursery use of imidacloprid applied to flowering plants can result in 793 to 1,368 times higher concentration compared to an imidacloprid seed treatment (7.6 ppb pollen in seed- treated canola), where most research has focused. These higher imidacloprid levels caused significant mortality in both 1X and 2X treatments in 3 lady beetle species, Coleomegilla maculata, Harmonia axyridis, and Hippodamia convergens, but not a fourth species, Coccinella septempunctata. Adult survival were not reduced for monarch, Danaus plexippus and painted lady, Vanessa cardui, butterflies, but larval survival was significantly reduced. The use of the neonicotinoid imidacloprid at greenhouse/nursery rates reduced survival of beneficial insects feeding on pollen and nectar and is incompatible with the principles of IPM

  19. Waste Package Misload Probability

    SciTech Connect

    J.K. Knudsen

    2001-11-20

    The objective of this calculation is to calculate the probability of occurrence for fuel assembly (FA) misloads (i.e., Fa placed in the wrong location) and FA damage during FA movements. The scope of this calculation is provided by the information obtained from the Framatome ANP 2001a report. The first step in this calculation is to categorize each fuel-handling events that occurred at nuclear power plants. The different categories are based on FAs being damaged or misloaded. The next step is to determine the total number of FAs involved in the event. Using the information, a probability of occurrence will be calculated for FA misload and FA damage events. This calculation is an expansion of preliminary work performed by Framatome ANP 2001a.

  20. Design and Analysis of Salmonid Tagging Studies in the Columbia Basin, Volume XIV; Appraisal of the Relationship between Tag Detection Efficiency at Bonneville Dam and the Precision in Estuarine and Marine Survival Estimates on Returning PIT Tagged Chinook Salmon, 2000 Technical Report.

    SciTech Connect

    Perez-Comas, Jose A.; Skalski, John R.

    2000-07-01

    In the advent of the installation of a PIT-tag interrogation system in the Cascades Island fish ladder at Bonneville Dam, this report provides guidance on the anticipated precision of salmonid estuarine and marine survival estimates, for various levels of system-wide adult detection probability at Bonneville Dam. Precision was characterized by the standard error of the survival estimates and the coefficient of variation of the survival estimates. The anticipated precision of salmonid estuarine and marine survival estimates was directly proportional to the number of PIT-tagged smolts released and to the system-wide adult detection efficiency at Bonneville Dam, as well as to the in-river juvenile survival above Lower Granite Dam. Moreover, for a given release size and system-wide adult detection efficiency, higher estuarine and marine survivals did also produce more precise survival estimates. With a system-wide detection probability of P{sub BA} = 1 at Bonneville Dam, the anticipated CVs for the estuarine and marine survival ranged between 41 and 88% with release sizes of 10,000 smolts. Only with the 55,000 smolts being released from sites close to Lower Granite Dam and under high estuarine and marine survival, could CVs of 20% be attained with system detection efficiencies of less than perfect detection (i.e., P{sub BA} < 1).

  1. Quality of Survival and Growth in Children and Young Adults in the PNET4 European Controlled Trial of Hyperfractionated Versus Conventional Radiation Therapy for Standard-Risk Medulloblastoma

    SciTech Connect

    Kennedy, Colin; Bull, Kim; Chevignard, Mathilde; Culliford, David; Dörr, Helmuth G.; Doz, François; Kortmann, Rolf-Dieter; Lannering, Birgitta; Massimino, Maura; Navajas Gutiérrez, Aurora; Rutkowski, Stefan; Spoudeas, Helen A.; Calaminus, Gabriele

    2014-02-01

    Purpose: To compare quality of survival in “standard-risk” medulloblastoma after hyperfractionated radiation therapy of the central nervous system with that after standard radiation therapy, combined with a chemotherapy regimen common to both treatment arms, in the PNET4 randomised controlled trial. Methods and Materials: Participants in the PNET4 trial and their parents/caregivers in 7 participating anonymized countries completed standardized questionnaires in their own language on executive function, health status, behavior, health-related quality of life, and medical, educational, employment, and social information. Pre- and postoperative neurologic status and serial heights and weights were also recorded. Results: Data were provided by 151 of 244 eligible survivors (62%) at a median age at assessment of 15.2 years and median interval from diagnosis of 5.8 years. Compared with standard radiation therapy, hyperfractionated radiation therapy was associated with lower (ie, better) z-scores for executive function in all participants (mean intergroup difference 0.48 SDs, 95% confidence interval 0.16-0.81, P=.004), but health status, behavioral difficulties, and health-related quality of life z-scores were similar in the 2 treatment arms. Data on hearing impairment were equivocal. Hyperfractionated radiation therapy was also associated with greater decrement in height z-scores (mean intergroup difference 0.43 SDs, 95% confidence interval 0.10-0.76, P=.011). Conclusions: Hyperfractionated radiation therapy was associated with better executive function and worse growth but without accompanying change in health status, behavior, or quality of life.

  2. Effects of individual quality, reproductive success and environmental variability on survival of a long-lived seabird.

    PubMed

    Lescroël, Amélie; Dugger, Katie M; Ballard, Grant; Ainley, David G

    2009-07-01

    1. Heterogeneity in individual quality (i.e. individuals having different performance levels that are consistent throughout life) can drive the demography of iteroparous species, but quality in the context of environmental variability has rarely been evaluated. 2. We investigated the demographic responses of a long-lived seabird, the Adélie penguin (Pygoscelis adeliae), to contrasting environmental conditions as a function of reproductive success, breeding quality (BQ) and experience. A continuous index of BQ (BQI) was developed to reflect an individual's ability, relative to others, to produce viable offspring. 3. First, we assessed the relative importance of costs of reproduction vs. heterogeneity in quality by comparing survival and reproductive probabilities among deferred, successful and unsuccessful breeders under 'demanding' conditions using multistate capture-mark-recapture modelling. Then, we quantified the influence of BQI on adult survival among experienced breeders vs. the whole study population under both 'normal' and 'demanding' conditions. 4. Higher survival rates were exhibited by successful (74-76%) compared to unsuccessful breeders (64%); the former also more frequently reproduced successfully at year t + 1. 5. From 1997 to 2006, adult survival ranged from 64-79%, with BQI accounting for 91% of variability in the entire study population, but only 17% in experienced breeders. The weakened relationship between BQI and survival in experienced breeders supports the theory that selection during the first reproductive event accounts for a more homogeneous pool of experienced breeders. 6. No significant effect of environmental covariates on survival was evident, suggesting that what appeared to be demanding conditions were within the range that could be buffered by this species. 7. For the first time in seabirds, a quadratic relationship between adult survival and BQI showed that adult survival is shaped by both heterogeneity in quality and reproductive

  3. Survival of radio-implanted drymarchon couperi (Eastern Indigo Snake) in relation to body size and sex

    USGS Publications Warehouse

    Hyslop, N.L.; Meyers, J.M.; Cooper, R.J.; Norton, Terry M.

    2009-01-01

    Drymarchon couperi (eastern indigo snake) has experienced population declines across its range primarily as a result of extensive habitat loss, fragmentation, and degradation. Conservation efforts for D. couperi have been hindered, in part, because of informational gaps regarding the species, including a lack of data on population ecology and estimates of demographic parameters such as survival. We conducted a 2- year radiotelemetry study of D. couperi on Fort Stewart Military Reservation and adjacent private lands located in southeastern Georgia to assess individual characteristics associated with probability of survival. We used known-fate modeling to estimate survival, and an information-theoretic approach, based on a priori hypotheses, to examine intraspecific differences in survival probabilities relative to individual covariates (sex, size, size standardized by sex, and overwintering location). Annual survival in 2003 and 2004 was 0.89 (95% CI = 0.73-0.97, n = 25) and 0.72 (95% CI = 0.52-0.86; n = 27), respectively. Results indicated that body size, standardized by sex, was the most important covariate determining survival of adult D. couperi, suggesting lower survival for larger individuals within each sex. We are uncertain of the mechanisms underlying this result, but possibilities may include greater resource needs for larger individuals within each sex, necessitating larger or more frequent movements, or a population with older individuals. Our results may also have been influenced by analysis limitations because of sample size, other sources of individual variation, or environmental conditions. ?? 2009 by The Herpetologists' League, Inc.

  4. Hyperprolinemic larvae of the drosophilid fly, Chymomyza costata, survive cryopreservation in liquid nitrogen

    PubMed Central

    Koštál, Vladimír; Zahradníčková, Helena; Šimek, Petr

    2011-01-01

    The larva of the drosophilid fly, Chymomyza costata, is probably the most complex metazoan organism that can survive submergence in liquid nitrogen (-196 °C) in a fully hydrated state. We examined the associations between the physiological and biochemical parameters of differently acclimated larvae and their freeze tolerance. Entering diapause is an essential and sufficient prerequisite for attaining high levels of survival in liquid nitrogen (23% survival to adult stage), although cold acclimation further improves this capacity (62% survival). Profiling of 61 different metabolites identified proline as a prominent compound whose concentration increased from 20 to 147 mM during diapause transition and subsequent cold acclimation. This study provides direct evidence for the essential role of proline in high freeze tolerance. We increased the levels of proline in the larval tissues by feeding larvae proline-augmented diets and found that this simple treatment dramatically improved their freeze tolerance. Cell and tissue survival following exposure to liquid nitrogen was evident in proline-fed nondiapause larvae, and survival to adult stage increased from 0% to 36% in proline-fed diapause-destined larvae. A significant statistical correlation was found between the whole-body concentration of proline, either natural or artificial, and survival to the adult stage in liquid nitrogen for diapause larvae. Differential scanning calorimetry analysis suggested that high proline levels, in combination with a relatively low content of osmotically active water and freeze dehydration, increased the propensity of the remaining unfrozen water to undergo a glass-like transition (vitrification) and thus facilitated the prevention of cryoinjury. PMID:21788482

  5. Hyperprolinemic larvae of the drosophilid fly, Chymomyza costata, survive cryopreservation in liquid nitrogen.

    PubMed

    Kostál, Vladimír; Zahradnícková, Helena; Šimek, Petr

    2011-08-01

    The larva of the drosophilid fly, Chymomyza costata, is probably the most complex metazoan organism that can survive submergence in liquid nitrogen (-196 °C) in a fully hydrated state. We examined the associations between the physiological and biochemical parameters of differently acclimated larvae and their freeze tolerance. Entering diapause is an essential and sufficient prerequisite for attaining high levels of survival in liquid nitrogen (23% survival to adult stage), although cold acclimation further improves this capacity (62% survival). Profiling of 61 different metabolites identified proline as a prominent compound whose concentration increased from 20 to 147 mM during diapause transition and subsequent cold acclimation. This study provides direct evidence for the essential role of proline in high freeze tolerance. We increased the levels of proline in the larval tissues by feeding larvae proline-augmented diets and found that this simple treatment dramatically improved their freeze tolerance. Cell and tissue survival following exposure to liquid nitrogen was evident in proline-fed nondiapause larvae, and survival to adult stage increased from 0% to 36% in proline-fed diapause-destined larvae. A significant statistical correlation was found between the whole-body concentration of proline, either natural or artificial, and survival to the adult stage in liquid nitrogen for diapause larvae. Differential scanning calorimetry analysis suggested that high proline levels, in combination with a relatively low content of osmotically active water and freeze dehydration, increased the propensity of the remaining unfrozen water to undergo a glass-like transition (vitrification) and thus facilitated the prevention of cryoinjury. PMID:21788482

  6. Probability mapping of contaminants

    SciTech Connect

    Rautman, C.A.; Kaplan, P.G.; McGraw, M.A.; Istok, J.D.; Sigda, J.M.

    1994-04-01

    Exhaustive characterization of a contaminated site is a physical and practical impossibility. Descriptions of the nature, extent, and level of contamination, as well as decisions regarding proposed remediation activities, must be made in a state of uncertainty based upon limited physical sampling. The probability mapping approach illustrated in this paper appears to offer site operators a reasonable, quantitative methodology for many environmental remediation decisions and allows evaluation of the risk associated with those decisions. For example, output from this approach can be used in quantitative, cost-based decision models for evaluating possible site characterization and/or remediation plans, resulting in selection of the risk-adjusted, least-cost alternative. The methodology is completely general, and the techniques are applicable to a wide variety of environmental restoration projects. The probability-mapping approach is illustrated by application to a contaminated site at the former DOE Feed Materials Production Center near Fernald, Ohio. Soil geochemical data, collected as part of the Uranium-in-Soils Integrated Demonstration Project, have been used to construct a number of geostatistical simulations of potential contamination for parcels approximately the size of a selective remediation unit (the 3-m width of a bulldozer blade). Each such simulation accurately reflects the actual measured sample values, and reproduces the univariate statistics and spatial character of the extant data. Post-processing of a large number of these equally likely statistically similar images produces maps directly showing the probability of exceeding specified levels of contamination (potential clean-up or personnel-hazard thresholds).

  7. Measurement Uncertainty and Probability

    NASA Astrophysics Data System (ADS)

    Willink, Robin

    2013-02-01

    Part I. Principles: 1. Introduction; 2. Foundational ideas in measurement; 3. Components of error or uncertainty; 4. Foundational ideas in probability and statistics; 5. The randomization of systematic errors; 6. Beyond the standard confidence interval; Part II. Evaluation of Uncertainty: 7. Final preparation; 8. Evaluation using the linear approximation; 9. Evaluation without the linear approximations; 10. Uncertainty information fit for purpose; Part III. Related Topics: 11. Measurement of vectors and functions; 12. Why take part in a measurement comparison?; 13. Other philosophies; 14. An assessment of objective Bayesian methods; 15. A guide to the expression of uncertainty in measurement; 16. Measurement near a limit - an insoluble problem?; References; Index.

  8. Public Attitudes toward Stuttering in Turkey: Probability versus Convenience Sampling

    ERIC Educational Resources Information Center

    Ozdemir, R. Sertan; St. Louis, Kenneth O.; Topbas, Seyhun

    2011-01-01

    Purpose: A Turkish translation of the "Public Opinion Survey of Human Attributes-Stuttering" ("POSHA-S") was used to compare probability versus convenience sampling to measure public attitudes toward stuttering. Method: A convenience sample of adults in Eskisehir, Turkey was compared with two replicates of a school-based, probability cluster…

  9. Long-term maintenance combination chemotherapy with OPEC/MPEC (vincristine or methotrexate, prednisolone, etoposide and cyclophosphamide) or with daily oral etoposide and prednisolone can improve survival and quality of life in adult T-cell leukemia/lymphoma.

    PubMed

    Matsushita, K; Matsumoto, T; Ohtsubo, H; Fujiwara, H; Imamura, N; Hidaka, S; Kukita, T; Tei, C; Matsumoto, M; Arima, N

    1999-12-01

    Acute leukemia and lymphoma varieties of adult T-cell leukemia/lymphoma (ATL) usually carry a poor prognosis. While etoposide is generally useful for treating ATL, especially as a daily oral maintenance regimen, etoposide has not proven effective in severe types of ATL efficient in some patients. Of 87 ATL patients whom we have treated, 51 had acute leukemia, 22 lymphoma and 14 progressive chronic leukemia. Seventy-nine patients were treated with a long term maintenance combination protocol, OPEC/MPEC (weekly doses of vincristine, 0.7 mg/m2 or methotrexate, 14 mg/m2; prednisolone, 20 mg/m2; etoposide, 70 mg/m2 and cyclophosphamide, 200 mg/m2). The other 8 patients, 3 with acute leukemia, 2 with lymphoma and 3 with progressive chronic leukemia, were treated with daily oral administration of 25 mg of etoposide and 10 mg of prednisolone (DOEP). The dose administered was modified in individual cases to maintain the granulocyte count and reduce the number of ATL cells. Considering both protocols, a complete response and a partial response were achieved in 31.0% and 58.6% patients, respectively. Median survival times (MST) of all patients and, acute leukemia, lymphoma and progressive chronic leukemia types were 7.5, 6.7, 9.6 and 12.4 months, respectively. Respective MST of patients treated with OPEC/MPEC or DOEP protocols were 7.1 and 18.0 months. Relatively normal WBC counts, lower lactate dehydrogenase concentration and normal calcium concentration, limited numbers of anatomic sites involved, good performance status and good response to chemotherapy were significantly associated with long survival time. Drug toxicity was not apparent, and about half of patients were treated in an outpatient setting. PMID:10613451

  10. Emptiness Formation Probability

    NASA Astrophysics Data System (ADS)

    Crawford, Nicholas; Ng, Stephen; Starr, Shannon

    2016-08-01

    We present rigorous upper and lower bounds on the emptiness formation probability for the ground state of a spin-1/2 Heisenberg XXZ quantum spin system. For a d-dimensional system we find a rate of decay of the order {exp(-c L^{d+1})} where L is the sidelength of the box in which we ask for the emptiness formation event to occur. In the {d=1} case this confirms previous predictions made in the integrable systems community, though our bounds do not achieve the precision predicted by Bethe ansatz calculations. On the other hand, our bounds in the case {d ≥ 2} are new. The main tools we use are reflection positivity and a rigorous path integral expansion, which is a variation on those previously introduced by Toth, Aizenman-Nachtergaele and Ueltschi.

  11. 3-[3-(3-florophenyl-2-propyn-1-ylthio)-1, 2, 5-thiadiazol-4-yl]-1, 2, 5, 6-tetrahydro-1- methylpyridine oxalate, a novel xanomeline derivative, improves neural cells proliferation and survival in adult mice

    PubMed Central

    Zhang, Xiaoliang; Gong, Qiang; Zhang, Shuang; Wang, Lin; Hu, Yinghe; Shen, Haiming; Dong, Suzhen

    2012-01-01

    The present study analyzed the influence of 3-[3-(3-florophenyl-2-propyn-1-ylthio)-1, 2, 5-thiadiazol-4-yl]-1, 2, 5, 6-tetrahydro-1-methylpyridine oxalate (EUK1001), a novel xanomeline derivative of the M1/M4 receptor agonist, on hippocampal neurogenesis in adult C57BL6 mice. Results showed that 15-day EUK1001 treatment via intraperitoneal injection promoted neural cell proliferation in the dentate gyrus, although cell differentiation did not change. The majority of bromodeoxyuridine-positive cells co-expressed the immature neuronal marker doublecortin. In addition, the level of neurogenesis in the subventricular zone was not altered. Brain-derived neurotrophic factor mRNA expression was up-regulated following EUK1001 treatment, but no change was observed in expression of camp-responsive element binding protein 1, paired box gene 6, vascular endothelial growth factor alpha, neurogenic differentiation factor 1, and wingless-related mouse mammary tumor virus integration site 3A mRNA. These experimental findings indicated that EUK1001 enhanced proliferation and survival of hippocampal cells, possibly by increasing brain-derived neurotrophic factor expression. PMID:25806054

  12. Age-specific survival and philopatry in three species of European ducks: a long-term study

    USGS Publications Warehouse

    Blums, P.; Mednis, A.; Bauga, I.; Nichols, J.D.; Hines, J.E.

    1996-01-01

    Capture-recapture and band recovery models were used to estimate age-specific survival probabilities for female Northern Shovelers (Anas clypeata), Common Pochards (Aythya ferina), and Tufted Ducks (Aythya.fuligula) at Engure Marsh, Latvia, in 1964-1993. We banded more than 65,100 day-old ducklings of both sexes and captured 10,211 incubating females (3,713 new bandings and 6,498 recaptures). We developed a set of 3-age capture-recapture models to estimate annual survival rates for female ducklings, yearlings (SY), and adults (ASY) using programs SURGE and SURVIV and selected parsimonious models using a method developed bv Akaike (1973). Survival rates of SY and ASY females were highest-for Tufted Ducks intermediate for Common Pochards, and lowest for Northern Shovelers. Survival rates of SY and ASY females varied in parallel for shovelers and pochards. We believe that much of the difference in survival estimates between SY and ASY birds was caused by mortality rather than permanent emigration. Estimates of day-old duckling survival, reflecting both mortality and permanent emigration, were 0.12 for shoveler, 0.06 for pochard, and 0.03 for Tufted Duck. For all species, duckling survival varied over years, but the pattern of variation was not similar to that of the other age classes. Estimates of survival using band recovery data for SY + ASY female pochards and Tufted Ducks were similar to the capture-recapturee stimates, suggestingt hat surviving females returned to the breeding marsh with probabilities approaching 1.

  13. A Tale of Two Probabilities

    ERIC Educational Resources Information Center

    Falk, Ruma; Kendig, Keith

    2013-01-01

    Two contestants debate the notorious probability problem of the sex of the second child. The conclusions boil down to explication of the underlying scenarios and assumptions. Basic principles of probability theory are highlighted.

  14. Age-specific survival of tundra swans on the lower Alaska Peninsula

    USGS Publications Warehouse

    Meixell, Brandt W.; Lindberg, Mark S.; Conn, Paul B.; Dau, Christian P.; Sarvis, John E.; Sowl, Kristine M.

    2013-01-01

    The population of Tundra Swans (Cygnus columbianus columbianus) breeding on the lower Alaska Peninsula represents the southern extremity of the species' range and is uniquely nonmigratory. We used data on recaptures, resightings, and recoveries of neck-collared Tundra Swans on the lower Alaska Peninsula to estimate collar loss, annual apparent survival, and other demographic parameters for the years 1978–1989. Annual collar loss was greater for adult males fitted with either the thinner collar type (0.34) or the thicker collar type (0.15) than for other age/sex classes (thinner: 0.10, thicker: 0.04). The apparent mean probability of survival of adults (0.61) was higher than that of immatures (0.41) and for both age classes varied considerably by year (adult range: 0.44–0.95, immature range: 0.25–0.90). To assess effects of permanent emigration by age and breeding class, we analyzed post hoc the encounter histories of swans known to breed in our study area. The apparent mean survival of known breeders (0.65) was generally higher than that of the entire marked sample but still varied considerably by year (range 0.26–1.00) and indicated that permanent emigration of breeding swans was likely. We suggest that reductions in apparent survival probability were influenced primarily by high and variable rates of permanent emigration and that immigration by swans from elsewhere may be important in sustaining a breeding population at and near Izembek National Wildlife Refuge.

  15. The Probability of Causal Conditionals

    ERIC Educational Resources Information Center

    Over, David E.; Hadjichristidis, Constantinos; Evans, Jonathan St. B. T.; Handley, Simon J.; Sloman, Steven A.

    2007-01-01

    Conditionals in natural language are central to reasoning and decision making. A theoretical proposal called the Ramsey test implies the conditional probability hypothesis: that the subjective probability of a natural language conditional, P(if p then q), is the conditional subjective probability, P(q [such that] p). We report three experiments on…

  16. Annual survival of Snail Kites in Florida: Radio telemetry versus capture-resighting data

    USGS Publications Warehouse

    Bennetts, R.E.; Dreitz, V.J.; Kitchens, W.M.; Hines, J.E.; Nichols, J.D.

    1999-01-01

    We estimated annual survival of Snail Kites (Rostrhamus sociabilis) in Florida using the Kaplan-Meier estimator with data from 271 radio-tagged birds over a three-year period and capture-recapture (resighting) models with data from 1,319 banded birds over a six-year period. We tested the hypothesis that survival differed among three age classes using both data sources. We tested additional hypotheses about spatial and temporal variation using a combination of data from radio telemetry and single- and multistrata capture-recapture models. Results from these data sets were similar in their indications of the sources of variation in survival, but they differed in some parameter estimates. Both data sources indicated that survival was higher for adults than for juveniles, but they did not support delineation of a subadult age class. Our data also indicated that survival differed among years and regions for juveniles but not for adults. Estimates of juvenile survival using radio telemetry data were higher than estimates using capture-recapture models for two of three years (1992 and 1993). Ancillary evidence based on censored birds indicated that some mortality of radio-tagged juveniles went undetected during those years, resulting in biased estimates. Thus, we have greater confidence in our estimates of juvenile survival using capture-recapture models. Precision of estimates reflected the number of parameters estimated and was surprisingly similar between radio telemetry and single-stratum capture-recapture models, given the substantial differences in sample sizes. Not having to estimate resighting probability likely offsets, to some degree, the smaller sample sizes from our radio telemetry data. Precision of capture-recapture models was lower using multistrata models where region-specific parameters were estimated than using single-stratum models, where spatial variation in parameters was not taken into account.

  17. Dispersion as a Survival Strategy

    NASA Astrophysics Data System (ADS)

    Junior, Valdivino Vargas; Machado, Fábio Prates; Roldán-Correa, Alejandro

    2016-08-01

    We consider stochastic growth models to represent population subject to catastrophes. We analyze the subject from different set ups considering or not spatial restrictions, whether dispersion is a good strategy to increase the population viability. We find out it strongly depends on the effect of a catastrophic event, the spatial constraints of the environment and the probability that each exposed individual survives when a disaster strikes.

  18. Dispersion as a Survival Strategy

    NASA Astrophysics Data System (ADS)

    Junior, Valdivino Vargas; Machado, Fábio Prates; Roldán-Correa, Alejandro

    2016-06-01

    We consider stochastic growth models to represent population subject to catastrophes. We analyze the subject from different set ups considering or not spatial restrictions, whether dispersion is a good strategy to increase the population viability. We find out it strongly depends on the effect of a catastrophic event, the spatial constraints of the environment and the probability that each exposed individual survives when a disaster strikes.

  19. Quantum probability and many worlds

    NASA Astrophysics Data System (ADS)

    Hemmo, Meir; Pitowsky, Itamar

    We discuss the meaning of probabilities in the many worlds interpretation of quantum mechanics. We start by presenting very briefly the many worlds theory, how the problem of probability arises, and some unsuccessful attempts to solve it in the past. Then we criticize a recent attempt by Deutsch to derive the quantum mechanical probabilities from the non-probabilistic parts of quantum mechanics and classical decision theory. We further argue that the Born probability does not make sense even as an additional probability rule in the many worlds theory. Our conclusion is that the many worlds theory fails to account for the probabilistic statements of standard (collapse) quantum mechanics.

  20. Nestling telomere shortening, but not telomere length, reflects developmental stress and predicts survival in wild birds

    PubMed Central

    Boonekamp, Jelle J.; Mulder, G. A.; Salomons, H. Martijn; Dijkstra, Cor; Verhulst, Simon

    2014-01-01

    Developmental stressors often have long-term fitness consequences, but linking offspring traits to fitness prospects has remained a challenge. Telomere length predicts mortality in adult birds, and may provide a link between developmental conditions and fitness prospects. Here, we examine the effects of manipulated brood size on growth, telomere dynamics and post-fledging survival in free-living jackdaws. Nestlings in enlarged broods achieved lower mass and lost 21% more telomere repeats relative to nestlings in reduced broods, showing that developmental stress accelerates telomere shortening. Adult telomere length was positively correlated with their telomere length as nestling (r = 0.83). Thus, an advantage of long telomeres in nestlings is carried through to adulthood. Nestling telomere shortening predicted post-fledging survival and recruitment independent of manipulation and fledgling mass. This effect was strong, with a threefold difference in recruitment probability over the telomere shortening range. By contrast, absolute telomere length was neither affected by brood size manipulation nor related to survival. We conclude that telomere loss, but not absolute telomere length, links developmental conditions to subsequent survival and suggest that telomere shortening may provide a key to unravelling the physiological causes of developmental effects on fitness. PMID:24789893

  1. Probability workshop to be better in probability topic

    NASA Astrophysics Data System (ADS)

    Asmat, Aszila; Ujang, Suriyati; Wahid, Sharifah Norhuda Syed

    2015-02-01

    The purpose of the present study was to examine whether statistics anxiety and attitudes towards probability topic among students in higher education level have an effect on their performance. 62 fourth semester science students were given statistics anxiety questionnaires about their perception towards probability topic. Result indicated that students' performance in probability topic is not related to anxiety level, which means that the higher level in statistics anxiety will not cause lower score in probability topic performance. The study also revealed that motivated students gained from probability workshop ensure that their performance in probability topic shows a positive improvement compared before the workshop. In addition there exists a significance difference in students' performance between genders with better achievement among female students compared to male students. Thus, more initiatives in learning programs with different teaching approaches is needed to provide useful information in improving student learning outcome in higher learning institution.

  2. Propensity, Probability, and Quantum Theory

    NASA Astrophysics Data System (ADS)

    Ballentine, Leslie E.

    2016-08-01

    Quantum mechanics and probability theory share one peculiarity. Both have well established mathematical formalisms, yet both are subject to controversy about the meaning and interpretation of their basic concepts. Since probability plays a fundamental role in QM, the conceptual problems of one theory can affect the other. We first classify the interpretations of probability into three major classes: (a) inferential probability, (b) ensemble probability, and (c) propensity. Class (a) is the basis of inductive logic; (b) deals with the frequencies of events in repeatable experiments; (c) describes a form of causality that is weaker than determinism. An important, but neglected, paper by P. Humphreys demonstrated that propensity must differ mathematically, as well as conceptually, from probability, but he did not develop a theory of propensity. Such a theory is developed in this paper. Propensity theory shares many, but not all, of the axioms of probability theory. As a consequence, propensity supports the Law of Large Numbers from probability theory, but does not support Bayes theorem. Although there are particular problems within QM to which any of the classes of probability may be applied, it is argued that the intrinsic quantum probabilities (calculated from a state vector or density matrix) are most naturally interpreted as quantum propensities. This does not alter the familiar statistical interpretation of QM. But the interpretation of quantum states as representing knowledge is untenable. Examples show that a density matrix fails to represent knowledge.

  3. Juvenile survival in a tropical population of roseate terns: Interannual variation and effect of tick parasitism

    USGS Publications Warehouse

    Monticelli, D.; Ramos, J.A.; Hines, J.E.; Nichols, J.D.; Spendelow, J.A.

    2008-01-01

    Many demographic studies on long-lived seabirds have focused on the estimation of adult survival, but much less is known about survival during the early years of life, especially in tropical species. We report analyses of a capture?recapture dataset of 685 roseate terns ringed as fledglings and adults between 1998 and 2005 on Aride Island, Seychelles, and recaptured/resighted at the same colony site over a 5 yr (2002 to 2006) period. A multistate model was used to estimate survival for different age classes, including juvenile (first-year) birds returning as non-breeding prospectors. The effect of infestation by parasites (ticks) on survival was also examined. Overall, the estimated return of first-year individuals to the natal colony was very variable, ranging from 2 to 22%. Conditioned on survival, the probability of returning from Age 2 yr onwards increased to 70%. Survival rates were best modeled as time-specific, with estimates varying from 0.02 to 1.00 (mean 0.69) in first-year birds with a marked negative effect of tick infestation. In older birds (minimum age of 2 yr), the annual estimates fell between 0.69 and 0.86 (mean 0.77). Using a components of variance approach for estimation of year-to-year variation, we found high temporal variability for first-year individuals (coefficient of variation [CV] = 65%) compared to much less variation in the survival rate of older birds (CV = 9%). These findings agree with the life-history prediction that demographic rates of juveniles are usually lower and more variable than those of older individuals. Our results are also consistent with the predicted negative effect of tick parasitism on juvenile survival. Compared with data from other roseate tern populations, survival over the first 2 yr (Age 0 to 2 yr) was 18 to 40% higher in this study, suggesting that a high `young? survival rate may be an important demographic trait in this tropical population to compensate for the low annual reproductive success. Our data show

  4. Juvenile survival in a tropical population of roseate terns: Interannual variation and effect of tick parasitism

    USGS Publications Warehouse

    Monticelli, D.; Ramos, J.A.; Hines, J.E.; Nichols, J.D.; Spendelow, J.A.

    2008-01-01

    Many demographic studies on long-lived seabirds have focused on the estimation of adult survival, but much less is known about survival during the early years of life, especially in tropical species. We report analyses of a capture-recapture dataset of 685 roseate terns ringed as fledglings and adults between 1998 and 2005 on Aride Island, Seychelles, and recaptured/resighted at the same colony site over a 5 yr (2002 to 2006) period. A multistate model was used to estimate survival for different age classes, including juvenile (first-year) birds returning as non-breeding prospectors. The effect of infestation by parasites (ticks) on survival was also examined. Overall, the estimated return of first-year individuals to the natal colony was very variable, ranging from 2 to 22%. Conditioned on survival, the probability of returning from Age 2 yr onwards increased to 70%. Survival rates were best modeled as time-specific, with estimates varying from 0.02 to 1.00 (mean 0.69) in first-year birds with a marked negative effect of tick infestation. In older birds (minimum age of 2 yr), the annual estimates fell between 0.69 and 0.86 (mean 0.77). Using a components of variance approach for estimation of year-to-year variation, we found high temporal variability for first-year individuals (coefficient of variation [CV] = 65%) compared to much less variation in the survival rate of older birds (CV = 9 %). These findings agree with the life-history prediction that demographic rates of juveniles are usually lower and more variable than those of older individuals. Our results are also consistent with the predicted negative effect of tick parasitism on juvenile survival. Compared with data from other roseate tern populations, survival over the first 2 yr (Age 0 to 2 yr) was 18 to 40% higher in this study, suggesting that a high 'young' survival rate may be an important demographic trait in this tropical population to compensate for the low annual reproductive success. Our data

  5. PROBABILITY SURVEYS, CONDITIONAL PROBABILITIES, AND ECOLOGICAL RISK ASSESSMENT

    EPA Science Inventory

    We show that probability-based environmental resource monitoring programs, such as U.S. Environmental Protection Agency's (U.S. EPA) Environmental Monitoring and Asscssment Program EMAP) can be analyzed with a conditional probability analysis (CPA) to conduct quantitative probabi...

  6. Probability Surveys, Conditional Probability, and Ecological Risk Assessment

    EPA Science Inventory

    We show that probability-based environmental resource monitoring programs, such as the U.S. Environmental Protection Agency’s (U.S. EPA) Environmental Monitoring and Assessment Program, and conditional probability analysis can serve as a basis for estimating ecological risk over ...

  7. Quantum correlations in terms of neutrino oscillation probabilities

    NASA Astrophysics Data System (ADS)

    Alok, Ashutosh Kumar; Banerjee, Subhashish; Uma Sankar, S.

    2016-08-01

    Neutrino oscillations provide evidence for the mode entanglement of neutrino mass eigenstates in a given flavour eigenstate. Given this mode entanglement, it is pertinent to consider the relation between the oscillation probabilities and other quantum correlations. In this work, we show that all the well-known quantum correlations, such as the Bell's inequality, are directly related to the neutrino oscillation probabilities. The results of the neutrino oscillation experiments, which measure the neutrino survival probability to be less than unity, imply Bell's inequality violation.

  8. The relationship between species detection probability and local extinction probability

    USGS Publications Warehouse

    Alpizar-Jara, R.; Nichols, J.D.; Hines, J.E.; Sauer, J.R.; Pollock, K.H.; Rosenberry, C.S.

    2004-01-01

    In community-level ecological studies, generally not all species present in sampled areas are detected. Many authors have proposed the use of estimation methods that allow detection probabilities that are <1 and that are heterogeneous among species. These methods can also be used to estimate community-dynamic parameters such as species local extinction probability and turnover rates (Nichols et al. Ecol Appl 8:1213-1225; Conserv Biol 12:1390-1398). Here, we present an ad hoc approach to estimating community-level vital rates in the presence of joint heterogeneity of detection probabilities and vital rates. The method consists of partitioning the number of species into two groups using the detection frequencies and then estimating vital rates (e.g., local extinction probabilities) for each group. Estimators from each group are combined in a weighted estimator of vital rates that accounts for the effect of heterogeneity. Using data from the North American Breeding Bird Survey, we computed such estimates and tested the hypothesis that detection probabilities and local extinction probabilities were negatively related. Our analyses support the hypothesis that species detection probability covaries negatively with local probability of extinction and turnover rates. A simulation study was conducted to assess the performance of vital parameter estimators as well as other estimators relevant to questions about heterogeneity, such as coefficient of variation of detection probabilities and proportion of species in each group. Both the weighted estimator suggested in this paper and the original unweighted estimator for local extinction probability performed fairly well and provided no basis for preferring one to the other.

  9. Risks and probabilities of breast cancer: short-term versus lifetime probabilities.

    PubMed Central

    Bryant, H E; Brasher, P M

    1994-01-01

    OBJECTIVE: To calculate age-specific short-term and lifetime probabilities of breast cancer among a cohort of Canadian women. DESIGN: Double decrement life table. SETTING: Alberta. SUBJECTS: Women with first invasive breast cancers registered with the Alberta Cancer Registry between 1985 and 1987. MAIN OUTCOME MEASURES: Lifetime probability of breast cancer from birth and for women at various ages; short-term (up to 10 years) probability of breast cancer for women at various ages. RESULTS: The lifetime probability of breast cancer is 10.17% at birth and peaks at 10.34% at age 25 years, after which it decreases owing to a decline in the number of years over which breast cancer risk will be experienced. However, the probability of manifesting breast cancer in the next year increases steadily from the age of 30 onward, reaching 0.36% at 85 years. The probability of manifesting the disease within the next 10 years peaks at 2.97% at age 70 and decreases thereafter, again owing to declining probabilities of surviving the interval. CONCLUSIONS: Given that the incidence of breast cancer among Albertan women during the study period was similar to the national average, we conclude that currently more than 1 in 10 women in Canada can expect to have breast cancer at some point during their life. However, risk varies considerably over a woman's lifetime, with most risk concentrated after age 49. On the basis of the shorter-term age-specific risks that we present, the clinician can put breast cancer risk into perspective for younger women and heighten awareness among women aged 50 years or more. PMID:8287343

  10. Probabilistic Survivability Versus Time Modeling

    NASA Technical Reports Server (NTRS)

    Joyner, James J., Sr.

    2015-01-01

    This technical paper documents Kennedy Space Centers Independent Assessment team work completed on three assessments for the Ground Systems Development and Operations (GSDO) Program to assist the Chief Safety and Mission Assurance Officer (CSO) and GSDO management during key programmatic reviews. The assessments provided the GSDO Program with an analysis of how egress time affects the likelihood of astronaut and worker survival during an emergency. For each assessment, the team developed probability distributions for hazard scenarios to address statistical uncertainty, resulting in survivability plots over time. The first assessment developed a mathematical model of probabilistic survivability versus time to reach a safe location using an ideal Emergency Egress System at Launch Complex 39B (LC-39B); the second used the first model to evaluate and compare various egress systems under consideration at LC-39B. The third used a modified LC-39B model to determine if a specific hazard decreased survivability more rapidly than other events during flight hardware processing in Kennedys Vehicle Assembly Building (VAB).Based on the composite survivability versus time graphs from the first two assessments, there was a soft knee in the Figure of Merit graphs at eight minutes (ten minutes after egress ordered). Thus, the graphs illustrated to the decision makers that the final emergency egress design selected should have the capability of transporting the flight crew from the top of LC 39B to a safe location in eight minutes or less. Results for the third assessment were dominated by hazards that were classified as instantaneous in nature (e.g. stacking mishaps) and therefore had no effect on survivability vs time to egress the VAB. VAB emergency scenarios that degraded over time (e.g. fire) produced survivability vs time graphs that were line with aerospace industry norms.

  11. The Probabilities of Conditionals Revisited

    ERIC Educational Resources Information Center

    Douven, Igor; Verbrugge, Sara

    2013-01-01

    According to what is now commonly referred to as "the Equation" in the literature on indicative conditionals, the probability of any indicative conditional equals the probability of its consequent of the conditional given the antecedent of the conditional. Philosophers widely agree in their assessment that the triviality arguments of…

  12. Minimizing the probable maximum flood

    SciTech Connect

    Woodbury, M.S.; Pansic, N. ); Eberlein, D.T. )

    1994-06-01

    This article examines Wisconsin Electric Power Company's efforts to determine an economical way to comply with Federal Energy Regulatory Commission requirements at two hydroelectric developments on the Michigamme River. Their efforts included refinement of the area's probable maximum flood model based, in part, on a newly developed probable maximum precipitation estimate.

  13. Decision analysis with approximate probabilities

    NASA Technical Reports Server (NTRS)

    Whalen, Thomas

    1992-01-01

    This paper concerns decisions under uncertainty in which the probabilities of the states of nature are only approximately known. Decision problems involving three states of nature are studied. This is due to the fact that some key issues do not arise in two-state problems, while probability spaces with more than three states of nature are essentially impossible to graph. The primary focus is on two levels of probabilistic information. In one level, the three probabilities are separately rounded to the nearest tenth. This can lead to sets of rounded probabilities which add up to 0.9, 1.0, or 1.1. In the other level, probabilities are rounded to the nearest tenth in such a way that the rounded probabilities are forced to sum to 1.0. For comparison, six additional levels of probabilistic information, previously analyzed, were also included in the present analysis. A simulation experiment compared four criteria for decisionmaking using linearly constrained probabilities (Maximin, Midpoint, Standard Laplace, and Extended Laplace) under the eight different levels of information about probability. The Extended Laplace criterion, which uses a second order maximum entropy principle, performed best overall.

  14. Probability of sea level rise

    SciTech Connect

    Titus, J.G.; Narayanan, V.K.

    1995-10-01

    The report develops probability-based projections that can be added to local tide-gage trends to estimate future sea level at particular locations. It uses the same models employed by previous assessments of sea level rise. The key coefficients in those models are based on subjective probability distributions supplied by a cross-section of climatologists, oceanographers, and glaciologists.

  15. Computation of Most Probable Numbers

    PubMed Central

    Russek, Estelle; Colwell, Rita R.

    1983-01-01

    A rapid computational method for maximum likelihood estimation of most-probable-number values, incorporating a modified Newton-Raphson method, is presented. The method offers a much greater reliability for the most-probable-number estimate of total viable bacteria, i.e., those capable of growth in laboratory media. PMID:6870242

  16. Persistence with Chytridiomycosis does not assure survival of direct-developing frogs.

    PubMed

    Longo, Ana V; Burrowes, Patricia A

    2010-06-01

    The chytrid fungus, Batrachochytrium dendrobatidis (Bd) has been linked to extinction and decline of numerous amphibians. We studied the population-level effects of Bd in two post-decline anuran species, Eleutherodactylus coqui and E. portoricensis, at El Yunque National Forest, Puerto Rico. Data on amphibian abundance was updated to report long-term population trends. Mark-recapture data was used to monitor Bd-infection status and estimate survival probabilities of infected versus uninfected adults. Prevalence of Bd (number of infected/total sampled) and individual infection level (number of zoospores) were compared among age classes at Palo Colorado Forest (661 m) and Elfin Forest (850 m). Results revealed that both species continued to decrease in Palo Colorado Forest, while in the Elfin Forest, E. portoricensis recuperated from drastic declines. Age class, season, and locality significantly predicted zoospore load. Age was also significantly associated with high zoospores loads among Bd-positive frogs, and the prevalence of Bd was higher in juveniles than adults in all populations studied. We suggest that early age represents a critical life stage in the survival of direct-developing frogs infected by this fungus. Survival probability was always higher for uninfected frogs, but recapture rates of infected versus uninfected adults were significantly different only in Palo Colorado, alerting that the negative effect of Bd infection under enzootic conditions is greater at mid-elevations. This work contributes to our understanding of how direct-developing amphibians persist with Bd, pointing to critical life stages and synergistic interactions that may induce fluctuations and/or declines in the wild. PMID:20585971

  17. How Life History Can Sway the Fixation Probability of Mutants.

    PubMed

    Li, Xiang-Yi; Kurokawa, Shun; Giaimo, Stefano; Traulsen, Arne

    2016-07-01

    In this work, we study the effects of demographic structure on evolutionary dynamics when selection acts on reproduction, survival, or both. In contrast to the previously discovered pattern that the fixation probability of a neutral mutant decreases while the population becomes younger, we show that a mutant with a constant selective advantage may have a maximum or a minimum of the fixation probability in populations with an intermediate fraction of young individuals. This highlights the importance of life history and demographic structure in studying evolutionary dynamics. We also illustrate the fundamental differences between selection on reproduction and selection on survival when age structure is present. In addition, we evaluate the relative importance of size and structure of the population in determining the fixation probability of the mutant. Our work lays the foundation for also studying density- and frequency-dependent effects in populations when demographic structures cannot be neglected. PMID:27129737

  18. Children's Probability Intuitions: Understanding the Expected Value of Complex Gambles.

    ERIC Educational Resources Information Center

    Schlottmann, Anne

    2001-01-01

    Examined how 6- to 9-year-olds and adults judged expected value of complex gambles in which alternative outcomes had different prizes. Found that participants at all ages used multiplication rule for integrating probability and value of each individual outcome, and based judgment of overall expected value on alternative outcomes. Even youngest…

  19. The probabilities of unique events.

    PubMed

    Khemlani, Sangeet S; Lotstein, Max; Johnson-Laird, Phil

    2012-01-01

    Many theorists argue that the probabilities of unique events, even real possibilities such as President Obama's re-election, are meaningless. As a consequence, psychologists have seldom investigated them. We propose a new theory (implemented in a computer program) in which such estimates depend on an intuitive non-numerical system capable only of simple procedures, and a deliberative system that maps intuitions into numbers. The theory predicts that estimates of the probabilities of conjunctions should often tend to split the difference between the probabilities of the two conjuncts. We report two experiments showing that individuals commit such violations of the probability calculus, and corroborating other predictions of the theory, e.g., individuals err in the same way even when they make non-numerical verbal estimates, such as that an event is highly improbable. PMID:23056224

  20. Transition probabilities of Br II

    NASA Technical Reports Server (NTRS)

    Bengtson, R. D.; Miller, M. H.

    1976-01-01

    Absolute transition probabilities of the three most prominent visible Br II lines are measured in emission. Results compare well with Coulomb approximations and with line strengths extrapolated from trends in homologous atoms.

  1. The Probabilities of Unique Events

    PubMed Central

    Khemlani, Sangeet S.; Lotstein, Max; Johnson-Laird, Phil

    2012-01-01

    Many theorists argue that the probabilities of unique events, even real possibilities such as President Obama's re-election, are meaningless. As a consequence, psychologists have seldom investigated them. We propose a new theory (implemented in a computer program) in which such estimates depend on an intuitive non-numerical system capable only of simple procedures, and a deliberative system that maps intuitions into numbers. The theory predicts that estimates of the probabilities of conjunctions should often tend to split the difference between the probabilities of the two conjuncts. We report two experiments showing that individuals commit such violations of the probability calculus, and corroborating other predictions of the theory, e.g., individuals err in the same way even when they make non-numerical verbal estimates, such as that an event is highly improbable. PMID:23056224

  2. VESPA: False positive probabilities calculator

    NASA Astrophysics Data System (ADS)

    Morton, Timothy D.

    2015-03-01

    Validation of Exoplanet Signals using a Probabilistic Algorithm (VESPA) calculates false positive probabilities and statistically validates transiting exoplanets. Written in Python, it uses isochrones [ascl:1503.010] and the package simpledist.

  3. Dinosaurs, Dinosaur Eggs, and Probability.

    ERIC Educational Resources Information Center

    Teppo, Anne R.; Hodgson, Ted

    2001-01-01

    Outlines several recommendations for teaching probability in the secondary school. Offers an activity that employs simulation by hand and using a programmable calculator in which geometry, analytical geometry, and discrete mathematics are explored. (KHR)

  4. Joint probabilities and quantum cognition

    SciTech Connect

    Acacio de Barros, J.

    2012-12-18

    In this paper we discuss the existence of joint probability distributions for quantumlike response computations in the brain. We do so by focusing on a contextual neural-oscillator model shown to reproduce the main features of behavioral stimulus-response theory. We then exhibit a simple example of contextual random variables not having a joint probability distribution, and describe how such variables can be obtained from neural oscillators, but not from a quantum observable algebra.

  5. Joint probabilities and quantum cognition

    NASA Astrophysics Data System (ADS)

    de Barros, J. Acacio

    2012-12-01

    In this paper we discuss the existence of joint probability distributions for quantumlike response computations in the brain. We do so by focusing on a contextual neural-oscillator model shown to reproduce the main features of behavioral stimulus-response theory. We then exhibit a simple example of contextual random variables not having a joint probability distribution, and describe how such variables can be obtained from neural oscillators, but not from a quantum observable algebra.

  6. Evaluation of microbial release probabilities

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Work undertaken to improve the estimation of the probability of release of microorganisms from unmanned Martian landing spacecraft is summarized. An analytical model is described for the development of numerical values for release parameters and release mechanisms applicable to flight missions are defined. Laboratory test data are used to evolve parameter values for use by flight projects in estimating numerical values for release probabilities. The analysis treats microbial burden located on spacecraft surfaces, between mated surfaces, and encapsulated within materials.

  7. Reliability analysis of redundant systems. [a method to compute transition probabilities

    NASA Technical Reports Server (NTRS)

    Yeh, H. Y.

    1974-01-01

    A method is proposed to compute the transition probability (the probability of partial or total failure) of parallel redundant system. The effect of geometry of the system, the direction of load, and the degree of redundancy on the probability of complete survival of parachute-like system are also studied. The results show that the probability of complete survival of three-member parachute-like system is very sensitive to the variation of horizontal angle of the load. However, it becomes very insignificant as the degree of redundancy increases.

  8. Progression free survival and functional outcome after surgical resection of intramedullary ependymomas.

    PubMed

    Abdullah, Kalil G; Lubelski, Daniel; Miller, Jacob; Steinmetz, Michael P; Shin, John H; Krishnaney, Ajit; Mroz, Thomas E; Benzel, Edward C

    2015-12-01

    We present a 15 year institutional analysis of the factors affecting progression free survival (PFS) and overall survival (OS) in patients undergoing attempted resection of adult intramedullary spinal cord ependymomas. Intramedullary spinal cord tumors are rare but important clinical entities, and ependymomas are the most commonly encountered intramedullary tumor. In total, 53 adult patients over the span of 15 years were analyzed for OS, PFS, and the effects of plane of dissection (POD) and gross total resection (GTR) on functional and long term outcomes. The mean age was 45 years and median follow-up was 54 months. The follow-up neurological outcome and modified McCormick scale were used to determine the functional outcome. Kaplan-Meier curves were used to calculate progression and survival. The overall ability to achieve GTR was significantly correlated to identification of an intraoperative POD (p<0.001). There was a trend towards increased PFS with the ability to achieve a GTR. There was no significant difference in the pre- and postoperative functional outcome scores. The ability to achieve a GTR is strongly correlated to the identification of a POD in ependymomas. There is a trend towards an increased probability of PFS in intramedullary spinal cord tumors when GTR is achieved. The resection of these tumors is likely to halt, but not reverse, neurological deterioration. PMID:26234635

  9. Upper respiratory tract disease, force of infection, and effects on survival of gopher tortoises.

    PubMed

    Ozgul, Arpat; Oli, Madan K; Bolker, Benjamin M; Perez-Heydrich, Carolina

    2009-04-01

    Upper respiratory tract disease (URTD) caused by Mycoplasma agassizii has been hypothesized to contribute to the decline of some wild populations of gopher tortoises (Gopherus polyphemus). However, the force of infection (FOI) and the effect of URTD on survival in free-ranging tortoise populations remain unknown. Using four years (2003-2006) of mark-recapture and epidemiological data collected from 10 populations of gopher tortoises in central Florida, USA, we estimated the FOI (probability per year of a susceptible tortoise becoming infected) and the effect of URTD (i.e., seropositivity to M. agassizii) on apparent survival rates. Sites with high (> or = 25%) seroprevalence had substantially higher FOI (0.22 +/- 0.03; mean +/- SE) than low (< 25%) seroprevalence sites (0.04 +/- 0.01). Our results provide the first quantitative evidence that the rate of transmission of M. agassizii is directly related to the seroprevalence of the population. Seropositive tortoises had higher apparent survival (0.99 +/- 0.0001) than seronegatives (0.88 +/- 0.03), possibly because seropositive tortoises represent individuals that survived the initial infection, developed chronic disease, and experienced lower mortality during the four-year span of our study. However, two lines of evidence suggested possible effects of mycoplasmal URTD on tortoise survival. First, one plausible model suggested that susceptible (seronegative) tortoises in high seroprevalence sites had lower apparent survival rates than did susceptible tortoises in low seroprevalence sites, indicating a possible acute effect of infection. Second, the number of dead tortoise remains detected during annual site surveys increased significantly with increasing site seroprevalence, from approximately 1 to approximately 5 shell remains per 100 individuals. If (as our results suggest) URTD in fact reduces adult survival, it could adversely influence the population dynamics and persistence of this late- maturing, long

  10. Joint probability distributions for projection probabilities of random orthonormal states

    NASA Astrophysics Data System (ADS)

    Alonso, L.; Gorin, T.

    2016-04-01

    The quantum chaos conjecture applied to a finite dimensional quantum system implies that such a system has eigenstates that show similar statistical properties as the column vectors of random orthogonal or unitary matrices. Here, we consider the different probabilities for obtaining a specific outcome in a projective measurement, provided the system is in one of its eigenstates. We then give analytic expressions for the joint probability density for these probabilities, with respect to the ensemble of random matrices. In the case of the unitary group, our results can be applied, also, to the phenomenon of universal conductance fluctuations, where the same mathematical quantities describe partial conductances in a two-terminal mesoscopic scattering problem with a finite number of modes in each terminal.

  11. Defensive platform size and survivability. [Platform survivability

    SciTech Connect

    Canavan, Gregory H.

    1988-06-01

    This report discusses the survivability of space platforms, concentrating on space based kinetic energy interceptors. It evaluates the efficacy of hardening, maneuver, self-defense, and deception in extending the survivability of platforms of varying sizes to expected threats, concluding that they should be adequate in the near and mid terms.

  12. Spatial patterns of coral survivorship: impacts of adult proximity versus other drivers of localized mortality.

    PubMed

    Gibbs, David A; Hay, Mark E

    2015-01-01

    Species-specific enemies may promote prey coexistence through negative distance- and density-dependent survival of juveniles near conspecific adults. We tested this mechanism by transplanting juvenile-sized fragments of the brooding corals Pocillopora damicornis and Seriatopora hystrix 3, 12, 24 and 182 cm up- and down-current of conspecific adults and monitoring their survival and condition over time. We also characterized the spatial distribution of P. damicornis and S. hystrix within replicate plots on three Fijian reef flats and measured the distribution of small colonies within 2 m of larger colonies of each species. Juvenile-sized transplants exhibited no differences in survivorship as a function of distance from adult P. damicornis or S. hystrix. Additionally, both P. damicornis and S. hystrix were aggregated rather than overdispersed on natural reefs. However, a pattern of juveniles being aggregated near adults while larger (and probably older) colonies were not suggests that greater mortality near large adults could occur over longer periods of time or that size-dependent mortality was occurring. While we found minimal evidence of greater mortality of small colonies near adult conspecifics in our transplant experiments, we did document hot-spots of species-specific corallivory. We detected spatially localized and temporally persistent predation on P. damicornis by the territorial triggerfish Balistapus undulatus. This patchy predation did not occur for S. hystrix. This variable selective regime in an otherwise more uniform environment could be one mechanism maintaining diversity of corals on Indo-Pacific reefs. PMID:26623193

  13. Spatial patterns of coral survivorship: impacts of adult proximity versus other drivers of localized mortality

    PubMed Central

    Gibbs, David A.

    2015-01-01

    Species-specific enemies may promote prey coexistence through negative distance- and density-dependent survival of juveniles near conspecific adults. We tested this mechanism by transplanting juvenile-sized fragments of the brooding corals Pocillopora damicornis and Seriatopora hystrix 3, 12, 24 and 182 cm up- and down-current of conspecific adults and monitoring their survival and condition over time. We also characterized the spatial distribution of P. damicornis and S. hystrix within replicate plots on three Fijian reef flats and measured the distribution of small colonies within 2 m of larger colonies of each species. Juvenile-sized transplants exhibited no differences in survivorship as a function of distance from adult P. damicornis or S. hystrix. Additionally, both P. damicornis and S. hystrix were aggregated rather than overdispersed on natural reefs. However, a pattern of juveniles being aggregated near adults while larger (and probably older) colonies were not suggests that greater mortality near large adults could occur over longer periods of time or that size-dependent mortality was occurring. While we found minimal evidence of greater mortality of small colonies near adult conspecifics in our transplant experiments, we did document hot-spots of species-specific corallivory. We detected spatially localized and temporally persistent predation on P. damicornis by the territorial triggerfish Balistapus undulatus. This patchy predation did not occur for S. hystrix. This variable selective regime in an otherwise more uniform environment could be one mechanism maintaining diversity of corals on Indo-Pacific reefs. PMID:26623193

  14. Imprecise probabilities in engineering analyses

    NASA Astrophysics Data System (ADS)

    Beer, Michael; Ferson, Scott; Kreinovich, Vladik

    2013-05-01

    Probabilistic uncertainty and imprecision in structural parameters and in environmental conditions and loads are challenging phenomena in engineering analyses. They require appropriate mathematical modeling and quantification to obtain realistic results when predicting the behavior and reliability of engineering structures and systems. But the modeling and quantification is complicated by the characteristics of the available information, which involves, for example, sparse data, poor measurements and subjective information. This raises the question whether the available information is sufficient for probabilistic modeling or rather suggests a set-theoretical approach. The framework of imprecise probabilities provides a mathematical basis to deal with these problems which involve both probabilistic and non-probabilistic information. A common feature of the various concepts of imprecise probabilities is the consideration of an entire set of probabilistic models in one analysis. The theoretical differences between the concepts mainly concern the mathematical description of the set of probabilistic models and the connection to the probabilistic models involved. This paper provides an overview on developments which involve imprecise probabilities for the solution of engineering problems. Evidence theory, probability bounds analysis with p-boxes, and fuzzy probabilities are discussed with emphasis on their key features and on their relationships to one another. This paper was especially prepared for this special issue and reflects, in various ways, the thinking and presentation preferences of the authors, who are also the guest editors for this special issue.

  15. Measure and probability in cosmology

    NASA Astrophysics Data System (ADS)

    Schiffrin, Joshua S.; Wald, Robert M.

    2012-07-01

    General relativity has a Hamiltonian formulation, which formally provides a canonical (Liouville) measure on the space of solutions. In ordinary statistical physics, the Liouville measure is used to compute probabilities of macrostates, and it would seem natural to use the similar measure arising in general relativity to compute probabilities in cosmology, such as the probability that the Universe underwent an era of inflation. Indeed, a number of authors have used the restriction of this measure to the space of homogeneous and isotropic universes with scalar field matter (minisuperspace)—namely, the Gibbons-Hawking-Stewart measure—to make arguments about the likelihood of inflation. We argue here that there are at least four major difficulties with using the measure of general relativity to make probability arguments in cosmology: (1) Equilibration does not occur on cosmological length scales. (2) Even in the minisuperspace case, the measure of phase space is infinite and the computation of probabilities depends very strongly on how the infinity is regulated. (3) The inhomogeneous degrees of freedom must be taken into account (we illustrate how) even if one is interested only in universes that are very nearly homogeneous. The measure depends upon how the infinite number of degrees of freedom are truncated, and how one defines “nearly homogeneous.” (4) In a Universe where the second law of thermodynamics holds, one cannot make use of our knowledge of the present state of the Universe to retrodict the likelihood of past conditions.

  16. Street Survival Skills Questionnaire for the Deaf.

    ERIC Educational Resources Information Center

    McCarron, Lawrence T.; Stall, Colleen H.

    Guidelines are given assessing the community living skills of deaf students through an adaptation of the Street Survival Skills Questionnaire (SSSQ), which was originally designed for developmentally disabled or handicapped adolescents and adults. Adaptations include consideration of situational factors (such as visual distractions) and the…

  17. Flood hazard probability mapping method

    NASA Astrophysics Data System (ADS)

    Kalantari, Zahra; Lyon, Steve; Folkeson, Lennart

    2015-04-01

    In Sweden, spatially explicit approaches have been applied in various disciplines such as landslide modelling based on soil type data and flood risk modelling for large rivers. Regarding flood mapping, most previous studies have focused on complex hydrological modelling on a small scale whereas just a few studies have used a robust GIS-based approach integrating most physical catchment descriptor (PCD) aspects on a larger scale. The aim of the present study was to develop methodology for predicting the spatial probability of flooding on a general large scale. Factors such as topography, land use, soil data and other PCDs were analysed in terms of their relative importance for flood generation. The specific objective was to test the methodology using statistical methods to identify factors having a significant role on controlling flooding. A second objective was to generate an index quantifying flood probability value for each cell, based on different weighted factors, in order to provide a more accurate analysis of potential high flood hazards than can be obtained using just a single variable. The ability of indicator covariance to capture flooding probability was determined for different watersheds in central Sweden. Using data from this initial investigation, a method to subtract spatial data for multiple catchments and to produce soft data for statistical analysis was developed. It allowed flood probability to be predicted from spatially sparse data without compromising the significant hydrological features on the landscape. By using PCD data, realistic representations of high probability flood regions was made, despite the magnitude of rain events. This in turn allowed objective quantification of the probability of floods at the field scale for future model development and watershed management.

  18. Interference of probabilities in dynamics

    SciTech Connect

    Zak, Michail

    2014-08-15

    A new class of dynamical systems with a preset type of interference of probabilities is introduced. It is obtained from the extension of the Madelung equation by replacing the quantum potential with a specially selected feedback from the Liouville equation. It has been proved that these systems are different from both Newtonian and quantum systems, but they can be useful for modeling spontaneous collective novelty phenomena when emerging outputs are qualitatively different from the weighted sum of individual inputs. Formation of language and fast decision-making process as potential applications of the probability interference is discussed.

  19. Probability as a Physical Motive

    NASA Astrophysics Data System (ADS)

    Martin, Peter

    2007-06-01

    Recent theoretical progress in nonequilibrium thermodynamics, linking thephysical principle of Maximum Entropy Production (“MEP”) to the information-theoretical“MaxEnt” principle of scientific inference, together with conjectures from theoreticalphysics that there may be no fundamental causal laws but only probabilities for physicalprocesses, and from evolutionary theory that biological systems expand “the adjacentpossible” as rapidly as possible, all lend credence to the proposition that probability shouldbe recognized as a fundamental physical motive. It is further proposed that spatial order andtemporal order are two aspects of the same thing, and that this is the essence of the secondlaw of thermodynamics.

  20. Knowledge typology for imprecise probabilities.

    SciTech Connect

    Wilson, G. D.; Zucker, L. J.

    2002-01-01

    When characterizing the reliability of a complex system there are often gaps in the data available for specific subsystems or other factors influencing total system reliability. At Los Alamos National Laboratory we employ ethnographic methods to elicit expert knowledge when traditional data is scarce. Typically, we elicit expert knowledge in probabilistic terms. This paper will explore how we might approach elicitation if methods other than probability (i.e., Dempster-Shafer, or fuzzy sets) prove more useful for quantifying certain types of expert knowledge. Specifically, we will consider if experts have different types of knowledge that may be better characterized in ways other than standard probability theory.

  1. Sexual comparisons in immune ability, survival and parasite intensity in two damselfly species.

    PubMed

    Córdoba-Aguilar, A; Contreras-Garduño, J; Peralta-Vázquez, H; Luna-González, A; Campa-Córdova, A I; Ascencio, F

    2006-08-01

    Recent evolutionary studies have suggested that females have a more robust immune system than males. Using two damselfly species (Hetaerina americana and Argia tezpi), we tested if females produced higher immune responses (as phenoloxidase and hydrolytic enzymes), had a higher survival (using a nylon implant inserted in the abdomen and measuring survival after 24h) and fewer parasites (gregarines and water mites) than males. We also tested whether immune differences should emerge in different body areas (thorax vs. abdomen) within each sex with the prediction that only females will differ with the abdomen having a higher immune response than their thorax since the former area, for ecological and physiological reasons, may be a target zone for increased immune investment. Animals were adults of approximately the same age. In both species, females were more immunocompetent than males, but only in H. americana females were immune responses greater in the abdomen than in the thorax. However, there were no differences in survival and parasite intensity or the probability of being parasitised between the sexes in either of the two species. Thus, this study lends partial support to the principle that females are better at defending than males despite the null difference in parasitism and survival. PMID:16843483

  2. Age-specific survival of male golden-cheeked warblers on the Fort Hood Military Reservation, Texas

    USGS Publications Warehouse

    Duarte, Adam; Hines, James E.; Nichols, James D.; Hatfield, Jeffrey S.; Weckerly, Floyd W.

    2014-01-01

    Population models are essential components of large-scale conservation and management plans for the federally endangered Golden-cheeked Warbler (Setophaga chrysoparia; hereafter GCWA). However, existing models are based on vital rate estimates calculated using relatively small data sets that are now more than a decade old. We estimated more current, precise adult and juvenile apparent survival (Φ) probabilities and their associated variances for male GCWAs. In addition to providing estimates for use in population modeling, we tested hypotheses about spatial and temporal variation in Φ. We assessed whether a linear trend in Φ or a change in the overall mean Φ corresponded to an observed increase in GCWA abundance during 1992-2000 and if Φ varied among study plots. To accomplish these objectives, we analyzed long-term GCWA capture-resight data from 1992 through 2011, collected across seven study plots on the Fort Hood Military Reservation using a Cormack-Jolly-Seber model structure within program MARK. We also estimated Φ process and sampling variances using a variance-components approach. Our results did not provide evidence of site-specific variation in adult Φ on the installation. Because of a lack of data, we could not assess whether juvenile Φ varied spatially. We did not detect a strong temporal association between GCWA abundance and Φ. Mean estimates of Φ for adult and juvenile male GCWAs for all years analyzed were 0.47 with a process variance of 0.0120 and a sampling variance of 0.0113 and 0.28 with a process variance of 0.0076 and a sampling variance of 0.0149, respectively. Although juvenile Φ did not differ greatly from previous estimates, our adult Φ estimate suggests previous GCWA population models were overly optimistic with respect to adult survival. These updated Φ probabilities and their associated variances will be incorporated into new population models to assist with GCWA conservation decision making.

  3. High intestinal lactase concentrations in adult Arbs in Saudi Arabia.

    PubMed

    Cook, G C; al-Torki, M T

    1975-07-19

    The maximum rise in blood glucose after 50 g lactose by mouth was determined in 40 adult Arabs. Out of 30 Bedouin, urban Saudi, and Yemeni and 9 of mixed ancestry (usually partly African), 25 (83%) and 2 (22%) respectively showed an increase of over 1-1 mmol/1 (20 mg/100 ml). In common with most northern Europeans and Hamitic people of northern Africa, Arabs in Saudi Arabia usually have high intestinal lactase concentrations in adult life. This persistence of high levels probably originated in the Arabian peninsula. Its selective advantage may have been associated with the fluid and calorie content of camels' milk, which is important for survival in desert nomads. PMID:1170003

  4. Stretching Probability Explorations with Geoboards

    ERIC Educational Resources Information Center

    Wheeler, Ann; Champion, Joe

    2016-01-01

    Students are faced with many transitions in their middle school mathematics classes. To build knowledge, skills, and confidence in the key areas of algebra and geometry, students often need to practice using numbers and polygons in a variety of contexts. Teachers also want students to explore ideas from probability and statistics. Teachers know…

  5. ESTIMATION OF AGE TRANSITION PROBABILITIES.

    ERIC Educational Resources Information Center

    ZINTER, JUDITH R.

    THIS NOTE DESCRIBES THE PROCEDURES USED IN DETERMINING DYNAMOD II AGE TRANSITION MATRICES. A SEPARATE MATRIX FOR EACH SEX-RACE GROUP IS DEVELOPED. THESE MATRICES WILL BE USED AS AN AID IN ESTIMATING THE TRANSITION PROBABILITIES IN THE LARGER DYNAMOD II MATRIX RELATING AGE TO OCCUPATIONAL CATEGORIES. THREE STEPS WERE USED IN THE PROCEDURE--(1)…

  6. Probability Simulation in Middle School.

    ERIC Educational Resources Information Center

    Lappan, Glenda; Winter, M. J.

    1980-01-01

    Two simulations designed to teach probability to middle-school age pupils are presented. The first simulates the one-on-one foul shot simulation in basketball; the second deals with collecting a set of six cereal box prizes by buying boxes containing one toy each. (MP)

  7. Some Surprising Probabilities from Bingo.

    ERIC Educational Resources Information Center

    Mercer, Joseph O.

    1993-01-01

    Investigates the probability of winning the largest prize at Bingo through a series of five simpler problems. Investigations are conducted with the aid of either BASIC computer programs, spreadsheets, or a computer algebra system such as Mathematica. Provides sample data tables to illustrate findings. (MDH)

  8. GPS: Geometry, Probability, and Statistics

    ERIC Educational Resources Information Center

    Field, Mike

    2012-01-01

    It might be said that for most occupations there is now less of a need for mathematics than there was say fifty years ago. But, the author argues, geometry, probability, and statistics constitute essential knowledge for everyone. Maybe not the geometry of Euclid, but certainly geometrical ways of thinking that might enable us to describe the world…

  9. Conditional Independence in Applied Probability.

    ERIC Educational Resources Information Center

    Pfeiffer, Paul E.

    This material assumes the user has the background provided by a good undergraduate course in applied probability. It is felt that introductory courses in calculus, linear algebra, and perhaps some differential equations should provide the requisite experience and proficiency with mathematical concepts, notation, and argument. The document is…

  10. Dynamic SEP event probability forecasts

    NASA Astrophysics Data System (ADS)

    Kahler, S. W.; Ling, A.

    2015-10-01

    The forecasting of solar energetic particle (SEP) event probabilities at Earth has been based primarily on the estimates of magnetic free energy in active regions and on the observations of peak fluxes and fluences of large (≥ M2) solar X-ray flares. These forecasts are typically issued for the next 24 h or with no definite expiration time, which can be deficient for time-critical operations when no SEP event appears following a large X-ray flare. It is therefore important to decrease the event probability forecast with time as a SEP event fails to appear. We use the NOAA listing of major (≥10 pfu) SEP events from 1976 to 2014 to plot the delay times from X-ray peaks to SEP threshold onsets as a function of solar source longitude. An algorithm is derived to decrease the SEP event probabilities with time when no event is observed to reach the 10 pfu threshold. In addition, we use known SEP event size distributions to modify probability forecasts when SEP intensity increases occur below the 10 pfu event threshold. An algorithm to provide a dynamic SEP event forecast, Pd, for both situations of SEP intensities following a large flare is derived.

  11. On the probability of cure for heavy-ion radiotherapy

    NASA Astrophysics Data System (ADS)

    Hanin, Leonid; Zaider, Marco

    2014-07-01

    The probability of a cure in radiation therapy (RT)—viewed as the probability of eventual extinction of all cancer cells—is unobservable, and the only way to compute it is through modeling the dynamics of cancer cell population during and post-treatment. The conundrum at the heart of biophysical models aimed at such prospective calculations is the absence of information on the initial size of the subpopulation of clonogenic cancer cells (also called stem-like cancer cells), that largely determines the outcome of RT, both in an individual and population settings. Other relevant parameters (e.g. potential doubling time, cell loss factor and survival probability as a function of dose) are, at least in principle, amenable to empirical determination. In this article we demonstrate that, for heavy-ion RT, microdosimetric considerations (justifiably ignored in conventional RT) combined with an expression for the clone extinction probability obtained from a mechanistic model of radiation cell survival lead to useful upper bounds on the size of the pre-treatment population of clonogenic cancer cells as well as upper and lower bounds on the cure probability. The main practical impact of these limiting values is the ability to make predictions about the probability of a cure for a given population of patients treated to newer, still unexplored treatment modalities from the empirically determined probability of a cure for the same or similar population resulting from conventional low linear energy transfer (typically photon/electron) RT. We also propose that the current trend to deliver a lower total dose in a smaller number of fractions with larger-than-conventional doses per fraction has physical limits that must be understood before embarking on a particular treatment schedule.

  12. A Hydroxylated Metabolite of Flame-Retardant PBDE-47 Decreases the Survival, Proliferation, and Neuronal Differentiation of Primary Cultured Adult Neural Stem Cells and Interferes with Signaling of ERK5 MAP Kinase and Neurotrophin 3

    PubMed Central

    Xia, Zhengui

    2013-01-01

    Polybrominated diphenyl ethers (PBDEs) are a group of organobromine compounds widely used as flame retardants. PBDE-47 is one of the most prominent PBDE congeners found in human tissues, and it can be transformed into several metabolites, including 6-OH-PBDE-47. Recent studies have shown that PBDE-47 is neurotoxic to animals and possibly humans. However, the basis for the neurotoxicity of PBDEs and their metabolites is unclear. For example, it is not known whether PBDEs affect adult neurogenesis, a process implicated in learning and memory and in olfactory behavior. In this study, we examined the toxicity of PBDEs for primary adult neural stem/progenitor cells (aNSCs) isolated from the subventricular zone (SVZ) of adult mice. We discovered that 6-OH-PBDE-47, but not its parent compound PBDE-47, is cytotoxic for aNCSs using MTS metabolism and cell number as a measure of cytotoxicity. Interestingly, 6-OH-PBDE-47 induced apoptosis at concentrations above 7.5μM inhibited proliferation at 2.5–5μM while suppressing neuronal and oligodendrocyte differentiation at submicromolar concentrations (≤ 1μM). The effect on proliferation was reversed upon removal of 6-OH-PBDE-47 and correlated with selective but reversible inhibition of ERK5 activation by mitogenic growth factors EGF and bFGF. 6-OH-PBDE-47 also inhibited the proneuronal differentiation effect of neurotrophin 3 (NT3) and NT3 activation of ERK5. Together, these data show that 6-OH-PBDE-47 is more toxic than its parent compound for SVZ-derived aNSCs and that it inhibits multiple aspects of adult neurogenesis. Furthermore, inhibition of ERK5 signaling may underlie the adverse effect of 6-OH-PBDE-47 on proliferation and neuronal differentiation. Our data suggest that exposure to PBDE-based flame retardants could cause neurotoxicity in the adult brain by interfering with adult neurogenesis. PMID:23564643

  13. A Survival Kit for Teaching English to Refugees. TECHNIQUES.

    ERIC Educational Resources Information Center

    Overbeck, Carla

    1984-01-01

    Adult basic education and English as a second language teachers, as well as volunteer tutors, can help new refugees acquire functional English through the use of a survival kit. The Literacy Volunteers of America's guide to teaching conversational English recommends these items for a survival kit: a written copy of student's name, address, and…

  14. Breeding-ground habitat conditions and the survival of mallards

    USGS Publications Warehouse

    Nichols, J.D.; Pospahala, R.S.; Hines, J.E.

    1982-01-01

    The relationship between habitat conditions in prairie breeding areas of North America and mallard (Anas platyrhynchos) survival rates was investigated. Annual survival-rate estimates for mallards generally were higher during years of high May pond numbers and low mallards-per-pond ratios than during years of low pond numbers and high ratios. This tendency was most pronounced among males. These results suggest that mallard survival probabilities may be affected by breeding-ground habitat conditions.

  15. Synergistic Interactions within Disturbed Habitats between Temperature, Relative Humidity and UVB Radiation on Egg Survival in a Diadromous Fish

    PubMed Central

    Hickford, Michael J. H.; Schiel, David R.

    2011-01-01

    Anthropogenic impacts, including urbanization, deforestation, farming, and livestock grazing have altered riparian margins worldwide. One effect of changes to riparian vegetation is that the ground-level light, temperature, and humidity environment has also been altered. Galaxias maculatus, one of the most widely distributed fishes of the southern hemisphere, lays eggs almost exclusively beneath riparian vegetation in tidally influenced reaches of rivers. We hypothesized that the survival of these eggs is greatly affected by the micro-environment afforded by vegetation, particularly relating to temperature, humidity and UVB radiation. We experimentally reduced riparian vegetation height and altered shading characteristics, tracked egg survival, and used small ground-level temperature, humidity and UVB sensors to relate survival to ground-level effects around egg masses. The ground-level physical environment was markedly different from the surrounding ambient conditions. Tall dense riparian vegetation modified ambient conditions to produce a buffered temperature regime with constant high relative humidity, generally above 90%, and negligible UVB radiation at ground-level. Where vegetation height was reduced, frequent high temperatures, low humidity, and high UVB irradiances reduced egg survival by up to 95%. Temperature effects on egg survival were probably indirect, through reduced humidity, because developing eggs are known to survive in a wide range of temperatures. In this study, it was remarkable how such small variations in relatively small sites could have such a large effect on egg survival. It appears that modifications to riparian vegetation and the associated changes in the physical conditions of egg laying sites are major mechanisms affecting egg survival. The impacts associated with vegetational changes through human-induced disturbances are complex yet potentially devastating. These effects are particularly important because they affect a very small

  16. Synergistic interactions within disturbed habitats between temperature, relative humidity and UVB radiation on egg survival in a diadromous fish.

    PubMed

    Hickford, Michael J H; Schiel, David R

    2011-01-01

    Anthropogenic impacts, including urbanization, deforestation, farming, and livestock grazing have altered riparian margins worldwide. One effect of changes to riparian vegetation is that the ground-level light, temperature, and humidity environment has also been altered. Galaxias maculatus, one of the most widely distributed fishes of the southern hemisphere, lays eggs almost exclusively beneath riparian vegetation in tidally influenced reaches of rivers. We hypothesized that the survival of these eggs is greatly affected by the micro-environment afforded by vegetation, particularly relating to temperature, humidity and UVB radiation. We experimentally reduced riparian vegetation height and altered shading characteristics, tracked egg survival, and used small ground-level temperature, humidity and UVB sensors to relate survival to ground-level effects around egg masses. The ground-level physical environment was markedly different from the surrounding ambient conditions. Tall dense riparian vegetation modified ambient conditions to produce a buffered temperature regime with constant high relative humidity, generally above 90%, and negligible UVB radiation at ground-level. Where vegetation height was reduced, frequent high temperatures, low humidity, and high UVB irradiances reduced egg survival by up to 95%. Temperature effects on egg survival were probably indirect, through reduced humidity, because developing eggs are known to survive in a wide range of temperatures. In this study, it was remarkable how such small variations in relatively small sites could have such a large effect on egg survival. It appears that modifications to riparian vegetation and the associated changes in the physical conditions of egg laying sites are major mechanisms affecting egg survival. The impacts associated with vegetational changes through human-induced disturbances are complex yet potentially devastating. These effects are particularly important because they affect a very small

  17. Surviving Atmospheric Spacecraft Breakup

    NASA Technical Reports Server (NTRS)

    Szewczyk, Nathaniel J.; Conley, Catharine A.

    2003-01-01

    In essence, to survival a spacecraft breakup an animal must not experience a lethal event. Much as with surviving aircraft breakup, dissipation of lethal forces via breakup of the craft around the organism is likely to greatly increase the odds of survival. As spacecraft can travel higher and faster than aircraft, it is often assumed that spacecraft breakup is not a survivable event. Similarly, the belief that aircraft breakup or crashes are not survivable events is still prevalent in the general population. As those of us involved in search and rescue know, it is possible to survive both aircraft breakup and crashes. Here we make the first report of an animal, C. elegans, surviving atmospheric breakup of the spacecraft supporting it and discuss both the lethal events these animals had to escape and the implications implied for search and rescue following spacecraft breakup.

  18. Life in varying environments: experimental evidence for delayed effects of juvenile environment on adult life history.

    PubMed

    Helle, Heikki; Koskela, Esa; Mappes, Tapio

    2012-05-01

    1. The effects of environment experienced during early development on phenotype as an adult has started to gain vast amounts of interest in various taxa. Some evidence on long-term effects of juvenile environment is available, but replicated experimental studies in wild animals are still lacking. 2. Here we report the first replicated experiment in wild mammals which examines the long-term effects of juvenile and adult environments on individual fitness (reproduction, survival and health). The early development of bank vole (Myodes glareolus) individuals took place in either food-supplemented or un-supplemented outdoor enclosures. After the summer, adult individuals were reciprocally changed to either a similar or opposite resource environment to overwinter. 3. Adult environment had an overriding effect on reproductive success of females so that females overwintering in food-supplemented enclosures had a higher probability of breeding and advanced the initiation of breeding. However, the characteristics of their litters were determined by juvenile environment: females initially grown in food-supplemented conditions subsequently produced larger litters with bigger pups and a male-biased sex ratio. 4. In males, individuals growing in un-supplemented conditions had the highest survival irrespective of adult environment during winter, whereas in females, neither the juvenile nor adult environments affected their survival significantly. The physiological condition of voles in spring, as determined by haematological parameters, was also differentially affected by juvenile (plasma proteins and male testosterone) and adult (haematocrit) environments. 5. Our results suggest that (i) life-history trajectories of voles are not strictly specialized to a certain environment and (ii) the plastic life-history responses to present conditions can actually be caused by delayed effects of the juvenile environment. More generally, the results are important for understanding

  19. Gender Dysphoria in Adults.

    PubMed

    Zucker, Kenneth J; Lawrence, Anne A; Kreukels, Baudewijntje P C

    2016-03-28

    Gender dysphoria (GD), a term that denotes persistent discomfort with one's biologic sex or assigned gender, replaced the diagnosis of gender identity disorder in the Diagnostic and Statistical Manual of Mental Disorders in 2013. Subtypes of GD in adults, defined by sexual orientation and age of onset, have been described; these display different developmental trajectories and prognoses. Prevalence studies conclude that fewer than 1 in 10,000 adult natal males and 1 in 30,000 adult natal females experience GD, but such estimates vary widely. GD in adults is associated with an elevated prevalence of comorbid psychopathology, especially mood disorders, anxiety disorders, and suicidality. Causal mechanisms in GD are incompletely understood, but genetic, neurodevelopmental, and psychosocial factors probably all contribute. Treatment of GD in adults, although largely standardized, is likely to evolve in response to the increasing diversity of persons seeking treatment, demands for greater client autonomy, and improved understanding of the benefits and limitations of current treatment modalities. PMID:26788901

  20. Strengths and Satisfaction across the Adult Lifespan

    ERIC Educational Resources Information Center

    Isaacowitz, Derek M.; Vaillant, George E.; Seligman, Martin E. P.

    2003-01-01

    Positive psychology has recently developed a classification of human strengths (Peterson & Seligman, in press). We aimed to evaluate these strengths by investigating the strengths and life satisfaction in three adult samples recruited from the community (young adult, middle-aged, and older adult), as well as in the surviving men of the Grant study…

  1. Probability densities in strong turbulence

    NASA Astrophysics Data System (ADS)

    Yakhot, Victor

    2006-03-01

    In this work we, using Mellin’s transform combined with the Gaussian large-scale boundary condition, calculate probability densities (PDFs) of velocity increments P(δu,r), velocity derivatives P(u,r) and the PDF of the fluctuating dissipation scales Q(η,Re), where Re is the large-scale Reynolds number. The resulting expressions strongly deviate from the Log-normal PDF P(δu,r) often quoted in the literature. It is shown that the probability density of the small-scale velocity fluctuations includes information about the large (integral) scale dynamics which is responsible for the deviation of P(δu,r) from P(δu,r). An expression for the function D(h) of the multifractal theory, free from spurious logarithms recently discussed in [U. Frisch, M. Martins Afonso, A. Mazzino, V. Yakhot, J. Fluid Mech. 542 (2005) 97] is also obtained.

  2. Probability, Information and Statistical Physics

    NASA Astrophysics Data System (ADS)

    Kuzemsky, A. L.

    2016-03-01

    In this short survey review we discuss foundational issues of the probabilistic approach to information theory and statistical mechanics from a unified standpoint. Emphasis is on the inter-relations between theories. The basic aim is tutorial, i.e. to carry out a basic introduction to the analysis and applications of probabilistic concepts to the description of various aspects of complexity and stochasticity. We consider probability as a foundational concept in statistical mechanics and review selected advances in the theoretical understanding of interrelation of the probability, information and statistical description with regard to basic notions of statistical mechanics of complex systems. It includes also a synthesis of past and present researches and a survey of methodology. The purpose of this terse overview is to discuss and partially describe those probabilistic methods and approaches that are used in statistical mechanics with the purpose of making these ideas easier to understanding and to apply.

  3. Factors affecting settling, survival, and viability of black bears reintroduced to Felsenthal National Wildlife Refuge, Arkansas

    USGS Publications Warehouse

    Wear, B.J.; Eastridge, R.; Clark, J.D.

    2005-01-01

    We used radiotelemetry and population modeling techniques to examine factors related to population establishment of black bears (Ursus americanus) reintroduced to Felsenthal National Wildlife Refuge (NWR), Arkansas. Our objectives were to determine whether settling (i.e., establishment of a home range at or near the release site), survival, recruitment, and population viability were related to age class of reintroduced bears, presence of cubs, time since release, or number of translocated animals. We removed 23 adult female black bears with 56 cubs from their winter dens at White River NWR and transported them 160 km to man-made den structures at Felsenthal NWR during spring 2000–2002. Total movement and average circuity of adult females decreased from 1 month, 6 months, and 1 year post-emergence (F2,14 =19.7, P < 0.001 and F2,14 =5.76, P=0.015, respectively). Mean first-year post-release survival of adult female bears was 0.624 (SE = 0.110, SEinterannual = 0.144), and the survival rate of their cubs was 0.750 (SE = 0.088, SEinterannual = 0.109). The homing rate (i.e., the proportion of bears that returned to White River NWR) was 13%. Annual survival for female bears that remained at the release site and survived >1-year post-release increased to 0.909 (SE = 0.097, SEinterannual=0.067; Z=3.5, P < 0.001). Based on stochastic population growth simulations, the average annual growth rate (λ) was 1.093 (SD = 0.053) and the probability of extinction with no additional stockings ranged from 0.56-1.30%. The bear population at Felsenthal NWR is at or above the number after which extinction risk declines dramatically, although additional releases of bears could significantly decrease time to population reestablishment. Poaching accounted for at least 3 of the 8 adult mortalities that we documented; illegal kills could be a significant impediment to population re-establishment at Felsenthal NWR should poaching rates escalate.

  4. Probability for primordial black holes

    NASA Astrophysics Data System (ADS)

    Bousso, R.; Hawking, S. W.

    1995-11-01

    We consider two quantum cosmological models with a massive scalar field: an ordinary Friedmann universe and a universe containing primordial black holes. For both models we discuss the complex solutions to the Euclidean Einstein equations. Using the probability measure obtained from the Hartle-Hawking no-boundary proposal we find that the only unsuppressed black holes start at the Planck size but can grow with the horizon scale during the roll down of the scalar field to the minimum.

  5. Relative transition probabilities of cobalt

    NASA Technical Reports Server (NTRS)

    Roig, R. A.; Miller, M. H.

    1974-01-01

    Results of determinations of neutral-cobalt transition probabilities measured relative to Co I 4150.43 A and Co II 4145.15 A, using a gas-driven shock tube as the spectroscopic light source. Results are presented for 139 Co I lines in the range from 3940 to 6640 A and 11 Co II lines in the range from 3840 to 4730 A, which are estimated to have reliabilities ranging from 8 to 50%.

  6. Comparing net survival estimators of cancer patients.

    PubMed

    Seppä, Karri; Hakulinen, Timo; Läärä, Esa; Pitkäniemi, Janne

    2016-05-20

    The net survival of a patient diagnosed with a given disease is a quantity often interpreted as the hypothetical survival probability in the absence of causes of death other than the disease. In a relative survival framework, net survival summarises the excess mortality that patients experience compared with their relevant reference population. Based on follow-up data from the Finnish Cancer Registry, we derived simulation scenarios that describe survival of patients in eight cancer sites reflecting different excess mortality patterns in order to compare the performance of the classical Ederer II estimator and the new estimator proposed by Pohar Perme et al. At 5 years, the age-standardised Ederer II estimator performed equally well as the Pohar Perme estimator with the exception of melanoma in which the Pohar Perme estimator had a smaller mean squared error (MSE). At 10 and 15 years, the age-standardised Ederer II performed most often better than the Pohar Perme estimator. The unstandardised Ederer II estimator had the largest MSE at 5 years. However, its MSE was often superior to those of the other estimators at 10 and 15 years, especially in sparse data. Both the Pohar Perme and the age-standardised Ederer II estimator are valid for 5-year net survival of cancer patients. For longer-term net survival, our simulation results support the use of the age-standardised Ederer II estimator. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26707551

  7. Survival during the Breeding Season: Nest Stage, Parental Sex, and Season Advancement Affect Reed Warbler Survival

    PubMed Central

    Wierucka, Kaja; Halupka, Lucyna; Klimczuk, Ewelina; Sztwiertnia, Hanna

    2016-01-01

    Avian annual survival has received much attention, yet little is known about seasonal patterns in survival, especially of migratory passerines. In order to evaluate survival rates and timing of mortality within the breeding season of adult reed warblers (Acrocephalus scirpaceus), mark-recapture data were collected in southwest Poland, between 2006 and 2012. A total of 612 individuals (304 females and 308 males) were monitored throughout the entire breeding season, and their capture-recapture histories were used to model survival rates. Males showed higher survival during the breeding season (0.985, 95% CI: 0.941–0.996) than females (0.869, 95% CI: 0.727–0.937). Survival rates of females declined with the progression of the breeding season (from May to August), while males showed constant survival during this period. We also found a clear pattern within the female (but not male) nesting cycle: survival was significantly lower during the laying, incubation, and nestling periods (0.934, 95% CI: 0.898–0.958), when birds spent much time on the nest, compared to the nest building and fledgling periods (1.000, 95% CI: 1.00–1.000), when we did not record any female mortality. These data (coupled with some direct evidence, like bird corpses or blood remains found next to/on the nest) may suggest that the main cause of adult mortality was on-nest predation. The calculated survival rates for both sexes during the breeding season were high compared to annual rates reported for this species, suggesting that a majority of mortality occurs at other times of the year, during migration or wintering. These results have implications for understanding survival variation within the reproductive period as well as general trends of avian mortality. PMID:26934086

  8. A new approach to the "apparent survival" problem: estimating true survival rates from mark-recapture studies.

    PubMed

    Gilroy, James J; Virzi, Thomas; Boulton, Rebecca L; Lockwood, Julie L

    2012-07-01

    Survival estimates generated from live capture-mark-recapture studies may be negatively biased due to the permanent emigration of marked individuals from the study area. In the absence of a robust analytical solution, researchers typically sidestep this problem by simply reporting estimates using the term "apparent survival." Here, we present a hierarchical Bayesian multistate model designed to estimate true survival by accounting for predicted rates of permanent emigration. Initially we use dispersal kernels to generate spatial projections of dispersal probability around each capture location. From these projections, we estimate emigration probability for each marked individual and use the resulting values to generate bias-adjusted survival estimates from individual capture histories. When tested using simulated data sets featuring variable detection probabilities, survival rates, and dispersal patterns, the model consistently eliminated negative biases shown by apparent survival estimates from standard models. When applied to a case study concerning juvenile survival in the endangered Cape Sable Seaside Sparrow (Ammodramus maritimus mirabilis), bias-adjusted survival estimates increased more than twofold above apparent survival estimates. Our approach is applicable to any capture-mark-recapture study design and should be particularly valuable for organisms with dispersive juvenile life stages. PMID:22919897

  9. On estimating the fracture probability of nuclear graphite components

    NASA Astrophysics Data System (ADS)

    Srinivasan, Makuteswara

    2008-10-01

    The properties of nuclear grade graphites exhibit anisotropy and could vary considerably within a manufactured block. Graphite strength is affected by the direction of alignment of the constituent coke particles, which is dictated by the forming method, coke particle size, and the size, shape, and orientation distribution of pores in the structure. In this paper, a Weibull failure probability analysis for components is presented using the American Society of Testing Materials strength specification for nuclear grade graphites for core components in advanced high-temperature gas-cooled reactors. The risk of rupture (probability of fracture) and survival probability (reliability) of large graphite blocks are calculated for varying and discrete values of service tensile stresses. The limitations in these calculations are discussed from considerations of actual reactor environmental conditions that could potentially degrade the specification properties because of damage due to complex interactions between irradiation, temperature, stress, and variability in reactor operation.

  10. Probability for Weather and Climate

    NASA Astrophysics Data System (ADS)

    Smith, L. A.

    2013-12-01

    Over the last 60 years, the availability of large-scale electronic computers has stimulated rapid and significant advances both in meteorology and in our understanding of the Earth System as a whole. The speed of these advances was due, in large part, to the sudden ability to explore nonlinear systems of equations. The computer allows the meteorologist to carry a physical argument to its conclusion; the time scales of weather phenomena then allow the refinement of physical theory, numerical approximation or both in light of new observations. Prior to this extension, as Charney noted, the practicing meteorologist could ignore the results of theory with good conscience. Today, neither the practicing meteorologist nor the practicing climatologist can do so, but to what extent, and in what contexts, should they place the insights of theory above quantitative simulation? And in what circumstances can one confidently estimate the probability of events in the world from model-based simulations? Despite solid advances of theory and insight made possible by the computer, the fidelity of our models of climate differs in kind from the fidelity of models of weather. While all prediction is extrapolation in time, weather resembles interpolation in state space, while climate change is fundamentally an extrapolation. The trichotomy of simulation, observation and theory which has proven essential in meteorology will remain incomplete in climate science. Operationally, the roles of probability, indeed the kinds of probability one has access too, are different in operational weather forecasting and climate services. Significant barriers to forming probability forecasts (which can be used rationally as probabilities) are identified. Monte Carlo ensembles can explore sensitivity, diversity, and (sometimes) the likely impact of measurement uncertainty and structural model error. The aims of different ensemble strategies, and fundamental differences in ensemble design to support of

  11. Probability of Detection Demonstration Transferability

    NASA Technical Reports Server (NTRS)

    Parker, Bradford H.

    2008-01-01

    The ongoing Mars Science Laboratory (MSL) Propellant Tank Penetrant Nondestructive Evaluation (NDE) Probability of Detection (POD) Assessment (NESC activity) has surfaced several issues associated with liquid penetrant POD demonstration testing. This presentation lists factors that may influence the transferability of POD demonstration tests. Initial testing will address the liquid penetrant inspection technique. Some of the factors to be considered in this task are crack aspect ratio, the extent of the crack opening, the material and the distance between the inspection surface and the inspector's eye.

  12. Probability, statistics, and computational science.

    PubMed

    Beerenwinkel, Niko; Siebourg, Juliane

    2012-01-01

    In this chapter, we review basic concepts from probability theory and computational statistics that are fundamental to evolutionary genomics. We provide a very basic introduction to statistical modeling and discuss general principles, including maximum likelihood and Bayesian inference. Markov chains, hidden Markov models, and Bayesian network models are introduced in more detail as they occur frequently and in many variations in genomics applications. In particular, we discuss efficient inference algorithms and methods for learning these models from partially observed data. Several simple examples are given throughout the text, some of which point to models that are discussed in more detail in subsequent chapters. PMID:22407706

  13. Adult Regularization of Inconsistent Input Depends on Pragmatic Factors

    ERIC Educational Resources Information Center

    Perfors, Amy

    2016-01-01

    In a variety of domains, adults who are given input that is only partially consistent do not discard the inconsistent portion (regularize) but rather maintain the probability of consistent and inconsistent portions in their behavior (probability match). This research investigates the possibility that adults probability match, at least in part,…

  14. Lectures on probability and statistics

    SciTech Connect

    Yost, G.P.

    1984-09-01

    These notes are based on a set of statistics lectures delivered at Imperial College to the first-year postgraduate students in High Energy Physics. They are designed for the professional experimental scientist. We begin with the fundamentals of probability theory, in which one makes statements about the set of possible outcomes of an experiment, based upon a complete a priori understanding of the experiment. For example, in a roll of a set of (fair) dice, one understands a priori that any given side of each die is equally likely to turn up. From that, we can calculate the probability of any specified outcome. We finish with the inverse problem, statistics. Here, one begins with a set of actual data (e.g., the outcomes of a number of rolls of the dice), and attempts to make inferences about the state of nature which gave those data (e.g., the likelihood of seeing any given side of any given die turn up). This is a much more difficult problem, of course, and one's solutions often turn out to be unsatisfactory in one respect or another.

  15. Measure and Probability in Cosmology

    NASA Astrophysics Data System (ADS)

    Schiffrin, Joshua; Wald, Robert

    2012-03-01

    General relativity has a Hamiltonian formulation, which formally provides a canonical (Liouville) measure on the space of solutions. A number of authors have used the restriction of this measure to the space of homogeneous and isotropic universes with scalar field matter (minisuperspace)---namely, the Gibbons-Hawking-Stewart measure---to make arguments about the likelihood of inflation. We argue here that there are at least four major difficulties with using the measure of general relativity to make probability arguments in cosmology: (1) Equilibration does not occur on cosmological length scales. (2) Even in the minisuperspace case, the measure of phase space is infinite and the computation of probabilities depends very strongly on how the infinity is regulated. (3) The inhomogeneous degrees of freedom must be taken into account even if one is interested only in universes that are very nearly homogeneous. The measure depends upon how the infinite number of degrees of freedom are truncated, and how one defines ``nearly homogeneous''. (4) In a universe where the second law of thermodynamics holds, one cannot make use of our knowledge of the present state of the universe to ``retrodict'' the likelihood of past conditions.

  16. Genetic variants determining survival and fertility in an adverse African environment: a population-based large-scale candidate gene association study

    PubMed Central

    Koopman, Jacob J.E.; Pijpe, Jeroen; Böhringer, Stefan; van Bodegom, David; Eriksson, Ulrika K.; Sanchez-Faddeev, Hernando; Ziem, Juventus B.; Zwaan, Bas; Slagboom, P. Eline; de Knijff, Peter; Westendorp, Rudi G.J.

    2016-01-01

    Human survival probability and fertility decline strongly with age. These life history traits have been shaped by evolution. However, research has failed to uncover a consistent genetic determination of variation in survival and fertility. As an explanation, such genetic determinants have been selected in adverse environments, in which humans have lived during most of their history, but are almost exclusively studied in populations in modern affluent environments. Here, we present a large-scale candidate gene association study in a rural African population living in an adverse environment. In 4387 individuals, we studied 4052 SNPs in 148 genes that have previously been identified as possible determinants of survival or fertility in animals or humans. We studied their associations with survival comparing newborns, middle-age adults, and old individuals. In women, we assessed their associations with reported and observed numbers of children. We found no statistically significant associations of these SNPs with survival between the three age groups nor with women's reported and observed fertility. Population stratification was unlikely to explain these results. Apart from a lack of power, we hypothesise that genetic heterogeneity of complex phenotypes and gene-environment interactions prevent the identification of genetic variants explaining variation in survival and fertility in humans. PMID:27356285

  17. Survival and band recovery rates of mallards in New Zealand

    USGS Publications Warehouse

    Nichols, J.D.; Williams, M.; Caithness, T.

    1990-01-01

    Mallards (Anas platyrhynchos ) were banded at 4 discrete study areas in New Zealand. We used hunting season recoveries in conjunction with band recovery models to estimate annual survival and recovery rates and to test hypotheses about sources of variation in these rates. Recovery rates varied among the 4 areas and from year to year within areas. Recovery rates were generally higher for young mallards than for adults, and recovery rates of males were higher than those of females. Survival rates varied among the 4 areas and from year to year within some areas. Survival rates of females were lower than those of males, but survival rates of young birds were not consistently lower than those of adults. Average survival rates over all 4 areas were generally lower than averages for North American mallards.

  18. Panspermia Survival Scenarios for Organisms that Survive Typical Hypervelocity Solar System Impact Events.

    NASA Astrophysics Data System (ADS)

    Pasini, D.

    2014-04-01

    Previous experimental studies have demonstrated the survivability of living cells during hypervelocity impact events, testing the panspermia and litho-panspermia hypotheses [1]. It has been demonstrated by the authors that Nannochloropsis Oculata Phytoplankton, a eukaryotic photosynthesizing autotroph found in the 'euphotic zone' (sunlit surface layers of oceans [2]), survive impacts up to 6.93 km s-1 (approx. shock pressure 40 GPa) [3, 4]. Also shown to survive impacts up to 5.49 km s-1 is the tardigrade species Hypsibius dujardini (a complex micro-animal consisting of 40,000 cells) [5, 6]. It has also been shown that they can survive sustained pressures up to 600 MPa using a water filled pressure capsule [7]. Additionally bacteria can survive impacts up to 5.4 km s-1 (~30 GPa) - albeit with a low probability of survival [1], and the survivability of yeast spores in impacts up to 7.4 km s-1 (~30 GPa) has also recently been demonstrated [8]. Other groups have also reported that the lichen Xanthoria elegans is able to survive shocks in similar pressure ranges (~40 GPa) [9]. Here we present various simulated impact regimes to show which scenarios are condusive to the panspermia hypothesis of the natural transfer of life (via an icy body) through space to an extraterrestrial environment.

  19. MSPI False Indication Probability Simulations

    SciTech Connect

    Dana Kelly; Kurt Vedros; Robert Youngblood

    2011-03-01

    This paper examines false indication probabilities in the context of the Mitigating System Performance Index (MSPI), in order to investigate the pros and cons of different approaches to resolving two coupled issues: (1) sensitivity to the prior distribution used in calculating the Bayesian-corrected unreliability contribution to the MSPI, and (2) whether (in a particular plant configuration) to model the fuel oil transfer pump (FOTP) as a separate component, or integrally to its emergency diesel generator (EDG). False indication probabilities were calculated for the following situations: (1) all component reliability parameters at their baseline values, so that the true indication is green, meaning that an indication of white or above would be false positive; (2) one or more components degraded to the extent that the true indication would be (mid) white, and “false” would be green (negative) or yellow (negative) or red (negative). In key respects, this was the approach taken in NUREG-1753. The prior distributions examined were the constrained noninformative (CNI) prior used currently by the MSPI, a mixture of conjugate priors, the Jeffreys noninformative prior, a nonconjugate log(istic)-normal prior, and the minimally informative prior investigated in (Kelly et al., 2010). The mid-white performance state was set at ?CDF = ?10 ? 10-6/yr. For each simulated time history, a check is made of whether the calculated ?CDF is above or below 10-6/yr. If the parameters were at their baseline values, and ?CDF > 10-6/yr, this is counted as a false positive. Conversely, if one or all of the parameters are set to values corresponding to ?CDF > 10-6/yr but that time history’s ?CDF < 10-6/yr, this is counted as a false negative indication. The false indication (positive or negative) probability is then estimated as the number of false positive or negative counts divided by the number of time histories (100,000). Results are presented for a set of base case parameter values

  20. Long-term survival after surgical aortic valve replacement among patients over 65 years of age

    PubMed Central

    Sharabiani, Mansour T A; Fiorentino, Francesca; Angelini, Gianni D; Patel, Nishith N

    2016-01-01

    Objective Surgical aortic valve replacement (AVR) remains the gold standard therapy for severe aortic stenosis. Long-term survival data following AVR is required. Our objective was to provide a detailed contemporary benchmark of long-term survival following AVR among elderly patients (≥65 years) in the UK. Methods We conducted a retrospective cohort study of 1815 adult patients undergoing surgical AVR± coronary artery bypass graft (CABG) surgery at a single UK centre between 1996 and 2011. Our main outcome was patient survival, which was assessed by linkage to census records at the Office for National Statistics. Results The mean age of the cohort was 75 (±5.6) years. Patients in the AVR alone group had a slightly higher median survival of 10.9 (95% CI 10.5 to 11.8) years than the AVR+CABG group which had a median survival of 9.6 (95% CI 8.7 to 10.1) years (p=0.001 of log-rank test (LRT) for equality of survivor functions). The presence of chronic kidney disease, severely impaired left ventricular function or being a current smoker were each associated with a ≥50% increased risk of long-term mortality. Comparison of our study cohort patients and the reference (operation year, age and gender matched) UK population suggested no difference in survival probability up to 8 years (p=0.55). However, for longer periods of follow-up, the difference became increasingly significant (p<0.0001). Conclusions Long-term survival following surgical AVR in patients over 65 years of age is excellent and up to 8 years is comparable to the matched general population. PMID:27042318

  1. Occupational Survival Skills

    ERIC Educational Resources Information Center

    Leach, James A.; Nelson, Robert E.

    1978-01-01

    The author describes a set of twelve curriculum modules called "Occupational Survival Skills" relating to the "human" aspects of work organizations. The modules were based on information from opinion surveys of workers, students, parents, and teachers on what occupational survival skills are and how to teach them. (MF)

  2. Associativity and normative credal probability.

    PubMed

    Snow, P

    2002-01-01

    Cox's Theorem is a widely cited motivation for probabilistic models of uncertain belief. The theorem relates the associativity of the logical connectives to that of the arithmetic operations of probability. Recent questions about the correctness of Cox's Theorem have been resolved, but there are new questions about one functional equation used by Cox in 1946. This equation is missing from his later work. Advances in knowledge since 1946 and changes in Cox's research interests explain the equation's disappearance. Other associativity-based motivations avoid functional equations altogether, and so may be more transparently applied to finite domains and discrete beliefs. A discrete counterpart of Cox's Theorem can be assembled from results that have been in the literature since 1959. PMID:18238098

  3. Survival analysis approach to account for non-exponential decay rate effects in lifetime experiments

    NASA Astrophysics Data System (ADS)

    Coakley, K. J.; Dewey, M. S.; Huber, M. G.; Huffer, C. R.; Huffman, P. R.; Marley, D. E.; Mumm, H. P.; O`Shaughnessy, C. M.; Schelhammer, K. W.; Thompson, A. K.; Yue, A. T.

    2016-03-01

    In experiments that measure the lifetime of trapped particles, in addition to loss mechanisms with exponential survival probability functions, particles can be lost by mechanisms with non-exponential survival probability functions. Failure to account for such loss mechanisms produces systematic measurement error and associated systematic uncertainties in these measurements. In this work, we develop a general competing risks survival analysis method to account for the joint effect of loss mechanisms with either exponential or non-exponential survival probability functions, and a method to quantify the size of systematic effects and associated uncertainties for lifetime estimates. As a case study, we apply our survival analysis formalism and method to the Ultra Cold Neutron lifetime experiment at NIST. In this experiment, neutrons can escape a magnetic trap before they decay due to a wall loss mechanism with an associated non-exponential survival probability function.

  4. Imprecise probability for non-commuting observables

    NASA Astrophysics Data System (ADS)

    Allahverdyan, Armen E.

    2015-08-01

    It is known that non-commuting observables in quantum mechanics do not have joint probability. This statement refers to the precise (additive) probability model. I show that the joint distribution of any non-commuting pair of variables can be quantified via upper and lower probabilities, i.e. the joint probability is described by an interval instead of a number (imprecise probability). I propose transparent axioms from which the upper and lower probability operators follow. The imprecise probability depend on the non-commuting observables, is linear over the state (density matrix) and reverts to the usual expression for commuting observables.

  5. Determination of the reliability of Ni-Cd batteries from survival data on cells fabricated 1964 - 1977

    NASA Technical Reports Server (NTRS)

    Jordan, A. S.; Osullivan, T. D.

    1983-01-01

    The probability of Ni-Cd battery survival was determined by researching survival data on cells fabricated from 1964-1977. A log of cell failure times were plotted against cumulative failure percentage and mean and standard deviation were determined.

  6. Longevity records and survival estimate of birds in a Guatemala rain forest

    USGS Publications Warehouse

    Robbins, C.S.; Dowell, B.; Hines, J.

    2002-01-01

    Birds were mist-netted for ten consecutive 'winter' seasons at two sites on Cerro San Gil and for three to nine seasons at eight other sites on the mountain. Sixteen nets were used at each site for three days; net locations were the same each year. From 1,255 subsequent-year recaptures we computed annual survival using the program MARK. A low annual survival of 0.26+0.03 for Long-tailed Hermit probably reflects extensive wandering in search of food. The only other residents with low survival rates were Ochre-bellied Flycatcher (0.32) and Olive-backed Euphonia (0.38). Other residents tested ranged from 0.49 for Red-capped Manakin to 0.67 for Stub-tailed Spadebill and are within ranges reported from other tropical sites. Rates for migrants were lower, ranging from 0.33 (Worm-eating Warbler) to 0.45 (Kentucky Warbler). Limiting the analysis to known territorial adults (birds that had already returned from a previous year), raised survival rates for residents an average of 0.05, whereas rates for wintering migratory species remained unchanged. The oldest birds recaptured were all residents: Scalythroated Leaftosser (9 years 9 months), Tawny-winged and Wedge-billed Woodcreepers, Northern Bentbill, Tawny-crowned Greenlet, and White-breasted Woodwren (8 years 9 months each). Ages over three years nine months were recorded for 46 species; for the majority of these, new maximum age records were established. A positive relationship was found between survival rate and maximum age and between sample size and maximum age

  7. Survival and metamorphosis of low-density populations of larval sea lampreys (Petromyzon marinus) in streams following lampricide treatment

    USGS Publications Warehouse

    Johnson, Nicholas S.; Swink, William D.; Brenden, Travis O.; Slade, Jeffrey W.; Steeves, Todd B.; Fodale, Michael F.; Jones, Michael L.

    2014-01-01

    Sea lamprey Petromyzon marinus control in the Great Lakes primarily involves application of lampricides to streams where larval production occurs to kill larvae prior to their metamorphosing and entering the lakes as parasites (juveniles). Because lampricides are not 100% effective, larvae that survive treatment maymetamorphose before streams are again treated. Larvae that survive treatment have not beenwidely studied, so their dynamics are notwell understood.Wetagged and released larvae in six Great Lake tributaries following lampricide treatment and estimated vital demographic rates using multistate tag-recovery models. Model-averaged larval survivals ranged from 56.8 to 57.6%. Model-averaged adult recovery rates, which were the product of juvenile survivals and adult capture probabilities, ranged from 6.8 to 9.3%. Using stochastic simulations, we estimated production of juvenile sea lampreys from a hypothetical population of treatment survivors under different growth conditions based on parameter estimates from this research. For fast-growing populations, juvenile production peaked 2 years after treatment. For slow-growing populations, juvenile production was approximately one-third that of fast-growing populations,with production not peaking until 4 years after treatment. Our results suggest that dynamics (i.e., survival, metamorphosis) of residual larval populations are very similar to those of untreated larval populations. Consequently, residual populations do not necessarily warrant special consideration for the purpose of sea lamprey control and can be ranked for treatment along with other populations. Consecutive lampricide treatments, which are under evaluation by the sea lamprey control program, would bemost effective for reducing juvenile production in large, fast-growing populations.

  8. Reading for Survival or How to Teach Your Students to Function in Society.

    ERIC Educational Resources Information Center

    James, Bobby M.

    Government survey results reveal that large numbers of adults in the United States do not possess the minimal survival and life-coping skills necessary to function successfully in daily living. Since reading is the most basic of all life survival skills, a thematic reading that emphasized consumer survival was developed in the fall of 1977 at…

  9. Survival rates of birds of tropical and temperate forests: will the dogma survive?

    USGS Publications Warehouse

    Karr, J.R.; Nichols, J.D.; Klimkiewicz, M.K.; Brawn, J.D.

    1990-01-01

    Survival rates of tropical forest birds are widely assumed to be high relative to the survival rates of temperate forest birds. Much life-history theory is based on this assumption despite the lack of empirical data to support it. We provide the first detailed comparison of survival rates of tropical and temperate forest birds based on extensive data bases and modern capture-recapture models. We find no support for the conventional wisdom. Because clutch size is only one component of reproductive rate, the frequently assumed, simple association between clutch size and adult survival rates should not necessarily be expected. Our results emphasize the need to consider components of fecundity in addition to clutch size when comparing the life histories of tropical and temperate birds and suggest similar considerations in the development of vertebrate life-history theory.

  10. Fusion probability in heavy nuclei

    NASA Astrophysics Data System (ADS)

    Banerjee, Tathagata; Nath, S.; Pal, Santanu

    2015-03-01

    Background: Fusion between two massive nuclei is a very complex process and is characterized by three stages: (a) capture inside the potential barrier, (b) formation of an equilibrated compound nucleus (CN), and (c) statistical decay of the CN leading to a cold evaporation residue (ER) or fission. The second stage is the least understood of the three and is the most crucial in predicting yield of superheavy elements (SHE) formed in complete fusion reactions. Purpose: A systematic study of average fusion probability, , is undertaken to obtain a better understanding of its dependence on various reaction parameters. The study may also help to clearly demarcate onset of non-CN fission (NCNF), which causes fusion probability, PCN, to deviate from unity. Method: ER excitation functions for 52 reactions leading to CN in the mass region 170-220, which are available in the literature, have been compared with statistical model (SM) calculations. Capture cross sections have been obtained from a coupled-channels code. In the SM, shell corrections in both the level density and the fission barrier have been included. for these reactions has been extracted by comparing experimental and theoretical ER excitation functions in the energy range ˜5 %-35% above the potential barrier, where known effects of nuclear structure are insignificant. Results: has been shown to vary with entrance channel mass asymmetry, η (or charge product, ZpZt ), as well as with fissility of the CN, χCN. No parameter has been found to be adequate as a single scaling variable to determine . Approximate boundaries have been obtained from where starts deviating from unity. Conclusions: This study quite clearly reveals the limits of applicability of the SM in interpreting experimental observables from fusion reactions involving two massive nuclei. Deviation of from unity marks the beginning of the domain of dynamical models of fusion. Availability of precise ER cross

  11. Children's probability intuitions: understanding the expected value of complex gambles.

    PubMed

    Schlottmann, A

    2001-01-01

    Two experiments used Information Integration Theory to study how children judge expected value of complex gambles in which alternative outcomes have different prizes. Six-year-olds, 9-year-olds and adults (N = 73 in Study 1, N = 28 in Study 2) saw chance games that involved shaking a marble in a bicolored tube. One prize was won if the marble stopped on blue, another if it stopped on yellow. Children judged how happy a puppet playing the game would be, with the prizes and probability of the blue and yellow outcomes varied factorially. Three main results appeared in both studies: First, participants in all age groups used the normatively prescribed multiplication rule for integrating probability and value of each individual outcome--a striking finding because multiplicative reasoning does not usually appear before 8 years of age in other domains. Second, all age groups based judgment of overall expected value meaningfully on both alternative outcomes, but there were individual differences--many participants deviated from the normative addition rule, showing risk seeking and risk averse patterns of judgment similar to the risk attitudes often found with adults. Third, even the youngest children took probability to be an abstract rather than physical property of the game. Overall, in contrast to the traditional view, the present results demonstrate functional understanding of probability and expected value in children as young as 5 or 6. These results contribute to the growing evidence on children's intuitive reasoning competence. This intuition can, on the one hand, support surprisingly precocious performance in young children, but it may also contribute to the biases evident in adults' judgment and decision. PMID:11280473

  12. Multivariate piecewise exponential survival modeling.

    PubMed

    Li, Yan; Panagiotou, Orestis A; Black, Amanda; Liao, Dandan; Wacholder, Sholom

    2016-06-01

    In this article, we develop a piecewise Poisson regression method to analyze survival data from complex sample surveys involving cluster-correlated, differential selection probabilities, and longitudinal responses, to conveniently draw inference on absolute risks in time intervals that are prespecified by investigators. Extensive simulations evaluate the developed methods with extensions to multiple covariates under various complex sample designs, including stratified sampling, sampling with selection probability proportional to a measure of size (PPS), and a multi-stage cluster sampling. We applied our methods to a study of mortality in men diagnosed with prostate cancer in the Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial to investigate whether a biomarker available from biospecimens collected near time of diagnosis stratifies subsequent risk of death. Poisson regression coefficients and absolute risks of mortality (and the corresponding 95% confidence intervals) for prespecified age intervals by biomarker levels are estimated. We conclude with a brief discussion of the motivation, methods, and findings of the study. PMID:26583951

  13. Multivariate Piecewise Exponential Survival Modeling

    PubMed Central

    Li, Yan; Panagiotou, Orestis A.; Black, Amanda; Liao, Dandan; Wacholder, Sholom

    2016-01-01

    Summary In this article, we develop a piecewise Poisson regression method to analyze survival data from complex sample surveys involving cluster-correlated, differential selection probabilities, and longitudinal responses, to conveniently draw inference on absolute risks in time intervals that are prespecified by investigators. Extensive simulations evaluate the developed methods with extensions to multiple covariates under various complex sample designs, including stratified sampling, sampling with selection probability proportional to a measure of size (PPS), and a multi-stage cluster sampling. We applied our methods to a study of mortality in men diagnosed with prostate cancer in the Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial to investigate whether a biomarker available from biospecimens collected near time of diagnosis stratifies subsequent risk of death. Poisson regression coefficients and absolute risks of mortality (and the corresponding 95% confidence intervals) for prespecified age intervals by biomarker levels are estimated. We conclude with a brief discussion of the motivation, methods, and findings of the study. PMID:26583951

  14. Effect of lead poisoning on spectacled elder survival rates

    USGS Publications Warehouse

    Grand, J.B.; Flint, P.L.; Petersen, M.R.; Moran, C.L.

    1998-01-01

    Spectacled eider (Somateria fischeri) populations on the Yukon-Kuskokwim Delta (Y-K Delta), Alaska, declined rapidly through the 1980s, and low adult female survival was suggested as the likely cause of the decline. We used mark-resighting techniques to study annual survival rates of adult female spectacled eiders at 2 sites on the Y-K Delta during 1993-96. Our data suggest survival rates may differ among sites. However, a model fit to a subset of data on females for which we knew lead levels in blood suggests lead exposure influences survival. Adult females exposed to lead prior to hatching their eggs survived at a much lower rate (0.44 ?? 0.10) each year than females not exposed to lead before hatch (0.78 ?? 0.05). We suggest most mortality from lead exposure occurs over winter, and the related reduction in adult survival may be impeding recovery of local populations. We encourage managers to curtail input of lead shot into the environment.

  15. Exploring the Overestimation of Conjunctive Probabilities

    PubMed Central

    Nilsson, Håkan; Rieskamp, Jörg; Jenny, Mirjam A.

    2013-01-01

    People often overestimate probabilities of conjunctive events. The authors explored whether the accuracy of conjunctive probability estimates can be improved by increased experience with relevant constituent events and by using memory aids. The first experiment showed that increased experience with constituent events increased the correlation between the estimated and the objective conjunctive probabilities, but that it did not reduce overestimation of conjunctive probabilities. The second experiment showed that reducing cognitive load with memory aids for the constituent probabilities led to improved estimates of the conjunctive probabilities and to decreased overestimation of conjunctive probabilities. To explain the cognitive process underlying people’s probability estimates, the configural weighted average model was tested against the normative multiplicative model. The configural weighted average model generates conjunctive probabilities that systematically overestimate objective probabilities although the generated probabilities still correlate strongly with the objective probabilities. For the majority of participants this model was better than the multiplicative model in predicting the probability estimates. However, when memory aids were provided, the predictive accuracy of the multiplicative model increased. In sum, memory tools can improve people’s conjunctive probability estimates. PMID:23460026

  16. Effects of lampricide exposure on the survival, growth, and behavior of the unionid mussels Elliptio complanata and Pyganadon cataracta

    USGS Publications Warehouse

    Waller, D.L.; Bills, T.D.; Boogaard, M.A.; Johnson, D.A.; Doolittle, T.C.J.

    2003-01-01

    The effects of a 12-h exposure to the lampricide 3-trifluoromethyl-4- nitrophenol (TFM) and a combination of TFM and 1% niclosamide (active ingredient in Bayluscide 70% wettable powder) on the short and long-term (10 mo post exposure) survival and behavior of two unionid freshwater mussel species Elliptio complanata and Pyganadon cataracta were measured. Growth of juvenile E. complanata mussels 10 months after exposure was also compared. Toxicity was determined after 12 h exposures at maximum concentrations from 2- to 2.5- fold higher than the LC99 for sea lamprey larvae. A logistic model was used to estimate the probability of survival among treatments, trials, species, and sizes. Mortality was minimal in all test concentrations of TFM alone and the TFM/1% niclosamide combination. Estimated survival decreased 6% for each unit increase in the relative toxicity of TFM. Survival was greater for E. complanata than for P. cataracta, and for adults relative to juveniles. Lampricide treatment caused narcotization of both mussels (defined as having gaped shells and an extended foot) in concentrations ??? LC99 for sea lamprey larvae and narcotization ranged from 0-50% among treatments. Recovery from narcosis was apparent by 12 h post-exposure and complete by 36 h post-exposure. The rate of growth of E. complanata over the 10-month post-exposure period did not vary among treatments.

  17. Effects of lampricide exposure on the survival, growth, and behavior of the unionid mussels Elliptio complanata and Pyganadon cataracta

    USGS Publications Warehouse

    Waller, D.L.; Bills, T.D.; Boogaard, M.A.; Johnson, D.A.; Doolittle, T.C.J.

    2003-01-01

    The effects of a 12-h exposure to the lampricide 3-trifluoromethyl-4-nitrophenol (TFM) and a combination of TFM and 1% niclosamide (active ingredient in Bayluscide 70% wettable powder) on the short and long-term (10 mo post exposure) survival and behavior of two unionid freshwater mussel species Elliptio complanata and Pyganadon cataracta were measured. Growth of juvenile E. complanata mussels 10 months after exposure was also compared. Toxicity was determined after 12 h exposures at maximum concentrations from 2- to 2.5- fold higher than the LC99 for sea lamprey larvae. A logistic model was used to estimate the probability of survival among treatments, trials, species, and sizes. Mortality was minimal in all test concentrations of TFM alone and the TFM/1% niclosamide combination. Estimated survival decreased 6% for each unit increase in the relative toxicity of TFM. Survival was greater for E. complanata than for P. cataracta, and for adults relative to juveniles. Lampricide treatment caused narcotization of both mussels (defined as having gaped shells and an extended foot) in concentrations greater than or equal to LC99 for sea lamprey larvae and narcotization ranged from 0-50% among treatments. Recovery from narcosis was apparent by 12 h post-exposure and complete by 36 h post-exposure. The rate of growth of E. complanata over the 10-month post-exposure period did not vary among treatments.

  18. Direct probability mapping of contaminants

    SciTech Connect

    Rautman, C.A.

    1993-09-17

    Exhaustive characterization of a contaminated site is a physical and practical impossibility. Descriptions of the nature, extent, and level of contamination, as well as decisions regarding proposed remediation activities, must be made in a state of uncertainty based upon limited physical sampling. Geostatistical simulation provides powerful tools for investigating contaminant levels, and in particular, for identifying and using the spatial interrelationships among a set of isolated sample values. This additional information can be used to assess the likelihood of encountering contamination at unsampled locations and to evaluate the risk associated with decisions to remediate or not to remediate specific regions within a site. Past operation of the DOE Feed Materials Production Center has contaminated a site near Fernald, Ohio, with natural uranium. Soil geochemical data have been collected as part of the Uranium-in-Soils Integrated Demonstration Project. These data have been used to construct a number of stochastic images of potential contamination for parcels approximately the size of a selective remediation unit. Each such image accurately reflects the actual measured sample values, and reproduces the univariate statistics and spatial character of the extant data. Post-processing of a large number of these equally likely, statistically similar images produces maps directly showing the probability of exceeding specified levels of contamination. Evaluation of the geostatistical simulations can yield maps representing the expected magnitude of the contamination for various regions and other information that may be important in determining a suitable remediation process or in sizing equipment to accomplish the restoration.

  19. Trajectory versus probability density entropy.

    PubMed

    Bologna, M; Grigolini, P; Karagiorgis, M; Rosa, A

    2001-07-01

    We show that the widely accepted conviction that a connection can be established between the probability density entropy and the Kolmogorov-Sinai (KS) entropy is questionable. We adopt the definition of density entropy as a functional of a distribution density whose time evolution is determined by a transport equation, conceived as the only prescription to use for the calculation. Although the transport equation is built up for the purpose of affording a picture equivalent to that stemming from trajectory dynamics, no direct use of trajectory time evolution is allowed, once the transport equation is defined. With this definition in mind we prove that the detection of a time regime of increase of the density entropy with a rate identical to the KS entropy is possible only in a limited number of cases. The proposals made by some authors to establish a connection between the two entropies in general, violate our definition of density entropy and imply the concept of trajectory, which is foreign to that of density entropy. PMID:11461383

  20. Trajectory versus probability density entropy

    NASA Astrophysics Data System (ADS)

    Bologna, Mauro; Grigolini, Paolo; Karagiorgis, Markos; Rosa, Angelo

    2001-07-01

    We show that the widely accepted conviction that a connection can be established between the probability density entropy and the Kolmogorov-Sinai (KS) entropy is questionable. We adopt the definition of density entropy as a functional of a distribution density whose time evolution is determined by a transport equation, conceived as the only prescription to use for the calculation. Although the transport equation is built up for the purpose of affording a picture equivalent to that stemming from trajectory dynamics, no direct use of trajectory time evolution is allowed, once the transport equation is defined. With this definition in mind we prove that the detection of a time regime of increase of the density entropy with a rate identical to the KS entropy is possible only in a limited number of cases. The proposals made by some authors to establish a connection between the two entropies in general, violate our definition of density entropy and imply the concept of trajectory, which is foreign to that of density entropy.

  1. Probability distributions of turbulent energy.

    PubMed

    Momeni, Mahdi; Müller, Wolf-Christian

    2008-05-01

    Probability density functions (PDFs) of scale-dependent energy fluctuations, P[deltaE(l)] , are studied in high-resolution direct numerical simulations of Navier-Stokes and incompressible magnetohydrodynamic (MHD) turbulence. MHD flows with and without a strong mean magnetic field are considered. For all three systems it is found that the PDFs of inertial range energy fluctuations exhibit self-similarity and monoscaling in agreement with recent solar-wind measurements [Hnat, Geophys. Res. Lett. 29, 86 (2002)]. Furthermore, the energy PDFs exhibit similarity over all scales of the turbulent system showing no substantial qualitative change of shape as the scale of the fluctuations varies. This is in contrast to the well-known behavior of PDFs of turbulent velocity fluctuations. In all three cases under consideration the P[deltaE(l)] resemble Lévy-type gamma distributions approximately Delta;{-1} exp(-|deltaE|/Delta)|deltaE|;{-gamma} The observed gamma distributions exhibit a scale-dependent width Delta(l) and a system-dependent gamma . The monoscaling property reflects the inertial-range scaling of the Elsässer-field fluctuations due to lacking Galilei invariance of deltaE . The appearance of Lévy distributions is made plausible by a simple model of energy transfer. PMID:18643170

  2. Predicting Clustered Dental Implant Survival Using Frailty Methods

    PubMed Central

    Chuang, S.-K.; Cai, T.

    2008-01-01

    The purpose of this study was to predict future implant survival using information on risk factors and on the survival status of an individual’s existing implant(s). We considered a retrospective cohort study with 677 individuals having 2349 implants placed. We proposed to predict the survival probabilities using the Cox proportional hazards frailty model, with three important risk factors: smoking status, timing of placement, and implant staging. For a non-smoking individual with 2 implants placed, an immediate implant and in one stage, the marginal probability that 1 implant would survive 12 months was 85.8% (95%CI: 77%, 91.7%), and the predicted joint probability of surviving for 12 months was 75.1% (95%CI: 62.1%, 84.7%). If 1 implant was placed earlier and had survived for 12 months, then the second implant had an 87.5% (95%CI: 80.3%, 92.4%) chance of surviving 12 months. Such conditional and joint predictions can assist in clinical decision-making for individuals. PMID:17122171

  3. Survival of falling robots

    NASA Technical Reports Server (NTRS)

    Cameron, Jonathan M.; Arkin, Ronald C.

    1992-01-01

    As mobile robots are used in more uncertain and dangerous environments, it will become important to design them so that they can survive falls. In this paper, we examine a number of mechanisms and strategies that animals use to withstand these potentially catastrophic events and extend them to the design of robots. A brief survey of several aspects of how common cats survive falls provides an understanding of the issues involved in preventing traumatic injury during a falling event. After outlining situations in which robots might fall, a number of factors affecting their survival are described. From this background, several robot design guidelines are derived. These include recommendations for the physical structure of the robot as well as requirements for the robot control architecture. A control architecture is proposed based on reactive control techniques and action-oriented perception that is geared to support this form of survival behavior.

  4. Survival Skills: Secondary.

    ERIC Educational Resources Information Center

    Curriculum Review, 1979

    1979-01-01

    Reviewed are five programs (textbooks, audiovisual materials, workbooks, video-cassettes) designed to improve academic survival skills in secondary students. Content emphasis, reading level, rationale, objectives, organization, instructional method, student evaluation, physical features, and recommendations are listed for each. (KC)

  5. Survival at Isle Royale.

    ERIC Educational Resources Information Center

    Ballone, Lena M.

    2001-01-01

    Describes a simulation based on the popular television show "Survivor" in which students work in groups and study physiological needs for human survival. Focuses on communication skills, problem solving, and cooperative learning. (YDS)

  6. Survival of falling robots

    NASA Astrophysics Data System (ADS)

    Cameron, Jonathan M.; Arkin, Ronald C.

    1992-02-01

    As mobile robots are used in more uncertain and dangerous environments, it will become important to design them so that they can survive falls. In this paper, we examine a number of mechanisms and strategies that animals use to withstand these potentially catastrophic events and extend them to the design of robots. A brief survey of several aspects of how common cats survive falls provides an understanding of the issues involved in preventing traumatic injury during a falling event. After outlining situations in which robots might fall, a number of factors affecting their survival are described. From this background, several robot design guidelines are derived. These include recommendations for the physical structure of the robot as well as requirements for the robot control architecture. A control architecture is proposed based on reactive control techniques and action-oriented perception that is geared to support this form of survival behavior.

  7. Surviving at extremes

    NASA Astrophysics Data System (ADS)

    Dougan, Lorna

    2015-11-01

    Wherever we look on Earth - even in the most inhospitable places - we find life. But how do organisms manage to survive such difficult conditions? Lorna Dougan explains how physicists are helping to unravel the properties of “extremophile” life.

  8. Delay and Probability Discounting as Candidate Markers for Dementia: An Initial Investigation

    PubMed Central

    Lindbergh, Cutter A.; Puente, Antonio N.; Gray, Joshua C.; Mackillop, James; Miller, L. Stephen

    2014-01-01

    The present study investigated delay discounting and probability discounting—behavioral economic indices of impulsivity and risk proneness, respectively—in 39 healthy older adults and 25 older adults with mild cognitive impairment (MCI). Relative to the healthy group, it was hypothesized that older adults with MCI would display greater levels of impulsivity, risk proneness, and response inconsistency. The MCI group was found to display a unique delay discounting profile characterized by increasing impulsivity with decreasing reward magnitude, such that cognitively impaired older adults were significantly more impulsive than healthy controls at the small reward magnitude. The two groups exhibited similar levels of probability discounting, though older adults with MCI were significantly less consistent in their risk preferences. The present findings shed light onto decision-making in pre-dementia disease stages and suggest that discounting performance holds potential to complement early diagnostic instruments, likely due to pathophysiological processes in relevant brain regions. PMID:25236720

  9. Surviving Operation Desert Storm

    SciTech Connect

    Vice, J. )

    1992-08-01

    The importance of aircraft survivability during the invasion of Iraq is examined detailing anecdotal evidence of susceptibility and vulnerability reduction. Among the aircraft used that were designed to be more survivable than their predecessors were the F-117, A-10, F/A-18, and the AH-64. Reduced vulnerability is incorporated into the aircraft designs in the form of damage tolerant components, redundancy, self-sealing fluid systems, and miniaturization.

  10. Adolescent Survival Expectations: Variations by Race, Ethnicity, and Nativity.

    PubMed

    Warner, Tara D; Swisher, Raymond R

    2015-12-01

    Adolescent survival expectations are linked to a range of problem behaviors, poor health, and later socioeconomic disadvantage, yet scholars have not examined how survival expectations are differentially patterned by race, ethnicity, and/or nativity. This is a critical omission given that many risk factors for low survival expectations are themselves stratified by race and ethnicity. Using the National Longitudinal Study of Adolescent to Adult Health, we modeled racial, ethnic, and immigrant group differences in trajectories of adolescent survival expectations and assess whether these differences are accounted for by family, neighborhood, and/or other risk factors (e.g., health care access, substance use, exposure to violence). Findings indicated that most racial, ethnic, and immigrant groups were more pessimistic about their survival than were non-Hispanic whites, with the exception of Cuban youth, who were the most optimistic. Foreign-born Mexican youth had the lowest survival expectations, contrary to expectations from the "healthy-immigrant" hypothesis. PMID:26582513

  11. THE BLACK HOLE FORMATION PROBABILITY

    SciTech Connect

    Clausen, Drew; Piro, Anthony L.; Ott, Christian D.

    2015-02-01

    A longstanding question in stellar evolution is which massive stars produce black holes (BHs) rather than neutron stars (NSs) upon death. It has been common practice to assume that a given zero-age main sequence (ZAMS) mass star (and perhaps a given metallicity) simply produces either an NS or a BH, but this fails to account for a myriad of other variables that may effect this outcome, such as spin, binarity, or even stochastic differences in the stellar structure near core collapse. We argue that instead a probabilistic description of NS versus BH formation may be better suited to account for the current uncertainties in understanding how massive stars die. We present an initial exploration of the probability that a star will make a BH as a function of its ZAMS mass, P {sub BH}(M {sub ZAMS}). Although we find that it is difficult to derive a unique P {sub BH}(M {sub ZAMS}) using current measurements of both the BH mass distribution and the degree of chemical enrichment by massive stars, we demonstrate how P {sub BH}(M {sub ZAMS}) changes with these various observational and theoretical uncertainties. We anticipate that future studies of Galactic BHs and theoretical studies of core collapse will refine P {sub BH}(M {sub ZAMS}) and argue that this framework is an important new step toward better understanding BH formation. A probabilistic description of BH formation will be useful as input for future population synthesis studies that are interested in the formation of X-ray binaries, the nature and event rate of gravitational wave sources, and answering questions about chemical enrichment.

  12. The Black Hole Formation Probability

    NASA Astrophysics Data System (ADS)

    Clausen, Drew; Piro, Anthony L.; Ott, Christian D.

    2015-02-01

    A longstanding question in stellar evolution is which massive stars produce black holes (BHs) rather than neutron stars (NSs) upon death. It has been common practice to assume that a given zero-age main sequence (ZAMS) mass star (and perhaps a given metallicity) simply produces either an NS or a BH, but this fails to account for a myriad of other variables that may effect this outcome, such as spin, binarity, or even stochastic differences in the stellar structure near core collapse. We argue that instead a probabilistic description of NS versus BH formation may be better suited to account for the current uncertainties in understanding how massive stars die. We present an initial exploration of the probability that a star will make a BH as a function of its ZAMS mass, P BH(M ZAMS). Although we find that it is difficult to derive a unique P BH(M ZAMS) using current measurements of both the BH mass distribution and the degree of chemical enrichment by massive stars, we demonstrate how P BH(M ZAMS) changes with these various observational and theoretical uncertainties. We anticipate that future studies of Galactic BHs and theoretical studies of core collapse will refine P BH(M ZAMS) and argue that this framework is an important new step toward better understanding BH formation. A probabilistic description of BH formation will be useful as input for future population synthesis studies that are interested in the formation of X-ray binaries, the nature and event rate of gravitational wave sources, and answering questions about chemical enrichment.

  13. Survival after Acute Hemodialysis in Pennsylvania, 2005–2007: A Retrospective Cohort Study

    PubMed Central

    Ramer, Sarah J.; Cohen, Elan D.; Chang, Chung-Chou H.; Unruh, Mark L.; Barnato, Amber E.

    2014-01-01

    Background Little is known about acute hemodialysis in the US. Here we describe predictors of receipt of acute hemodialysis in one state and estimate the marginal impact of acute hemodialysis on survival after accounting for confounding due to illness severity. Materials and Methods This is a retrospective cohort study of acute-care hospitalizations in Pennsylvania from October 2005 to December 2007 using data from the Pennsylvania Health Care Cost Containment Council. Exposure variable is acute hemodialysis; dependent variable is survival following acute hemodialysis. We used multivariable logistic regression to determine propensity to receive acute hemodialysis and then, for a Cox proportional hazards model, matched acute hemodialysis and non-acute hemodialysis patients 1∶5 on this propensity. Results In 2,131,248 admissions of adults without end-stage renal disease, there were 6,657 instances of acute hemodialysis. In analyses adjusted for predicted probability of death upon admission plus other covariates and stratified on age, being male, black, and insured were independent predictors of receipt of acute hemodialysis. One-year post-admission mortality was 43% for those receiving acute hemodialysis, compared to 13% among those not receiving acute hemodialysis. After matching on propensity to receive acute hemodialysis and adjusting for predicted probability of death upon admission, patients who received acute hemodialysis had a higher risk of death than patients who did not over at least 1 year of follow-up (hazard ratio 1·82, 95% confidence interval 1·68–1·97). Conclusions In a populous US state, receipt of acute hemodialysis varied by age, sex, race, and insurance status even after adjustment for illness severity. In a comparison of patients with similar propensity to receive acute hemodialysis, those who did receive it were less likely to survive than those who did not. These findings raise questions about reasons for lack of benefit. PMID:25141028

  14. The Probability Distribution for a Biased Spinner

    ERIC Educational Resources Information Center

    Foster, Colin

    2012-01-01

    This article advocates biased spinners as an engaging context for statistics students. Calculating the probability of a biased spinner landing on a particular side makes valuable connections between probability and other areas of mathematics. (Contains 2 figures and 1 table.)

  15. Mallard survival from local to immature stage in southwestern Saskatchewan

    USGS Publications Warehouse

    Hestbeck, J.B.; Dzubin, A.; Gollop, J.B.; Nichols, J.D.

    1989-01-01

    We used 3,670 reciveries from 32,647 bandings of mallards in southwestern Saskatchewan during 1956-59 to estimate the probability of surviving from the local, flightless stage to the flighted, immature stage. The probability of surviving from the local to the immature stage was 0.84 +/- 0.05 (SE) for males and females. The geographic distribution of direct recoveries was similar for the birds banded as local and immature. Probabilities of surivival for banded mallards can only be estimated from late summer to late summer. The estimate of survival from local to immature stage fills a gap in our knowledge of mallard mortality from female-brood breakup to the time of banding in late summer.

  16. Survival Rates for Thymus Cancer

    MedlinePlus

    ... staged? Next Topic How is thymus cancer treated? Survival rates for thymus cancer Survival rates are often ... into account. Stage of thymoma 5-year observed survival rate I 74% II 73% III 64% IV ...

  17. Probability of detection of nests and implications for survey design

    USGS Publications Warehouse

    Smith, P.A.; Bart, J.; Lanctot, Richard B.; McCaffery, B.J.; Brown, S.

    2009-01-01

    Surveys based on double sampling include a correction for the probability of detection by assuming complete enumeration of birds in an intensively surveyed subsample of plots. To evaluate this assumption, we calculated the probability of detecting active shorebird nests by using information from observers who searched the same plots independently. Our results demonstrate that this probability varies substantially by species and stage of the nesting cycle but less by site or density of nests. Among the species we studied, the estimated single-visit probability of nest detection during the incubation period varied from 0.21 for the White-rumped Sandpiper (Calidris fuscicollis), the most difficult species to detect, to 0.64 for the Western Sandpiper (Calidris mauri), the most easily detected species, with a mean across species of 0.46. We used these detection probabilities to predict the fraction of persistent nests found over repeated nest searches. For a species with the mean value for detectability, the detection rate exceeded 0.85 after four visits. This level of nest detection was exceeded in only three visits for the Western Sandpiper, but six to nine visits were required for the White-rumped Sandpiper, depending on the type of survey employed. Our results suggest that the double-sampling method's requirement of nearly complete counts of birds in the intensively surveyed plots is likely to be met for birds with nests that survive over several visits of nest searching. Individuals with nests that fail quickly or individuals that do not breed can be detected with high probability only if territorial behavior is used to identify likely nesting pairs. ?? The Cooper Ornithological Society, 2009.

  18. Subjective and objective probabilities in quantum mechanics

    SciTech Connect

    Srednicki, Mark

    2005-05-15

    We discuss how the apparently objective probabilities predicted by quantum mechanics can be treated in the framework of Bayesian probability theory, in which all probabilities are subjective. Our results are in accord with earlier work by Caves, Fuchs, and Schack, but our approach and emphasis are different. We also discuss the problem of choosing a noninformative prior for a density matrix.

  19. Using Playing Cards to Differentiate Probability Interpretations

    ERIC Educational Resources Information Center

    López Puga, Jorge

    2014-01-01

    The aprioristic (classical, naïve and symmetric) and frequentist interpretations of probability are commonly known. Bayesian or subjective interpretation of probability is receiving increasing attention. This paper describes an activity to help students differentiate between the three types of probability interpretations.

  20. Illustrating Basic Probability Calculations Using "Craps"

    ERIC Educational Resources Information Center

    Johnson, Roger W.

    2006-01-01

    Instructors may use the gambling game of craps to illustrate the use of a number of fundamental probability identities. For the "pass-line" bet we focus on the chance of winning and the expected game length. To compute these, probabilities of unions of disjoint events, probabilities of intersections of independent events, conditional probabilities…

  1. Pre-Service Teachers' Conceptions of Probability

    ERIC Educational Resources Information Center

    Odafe, Victor U.

    2011-01-01

    Probability knowledge and skills are needed in science and in making daily decisions that are sometimes made under uncertain conditions. Hence, there is the need to ensure that the pre-service teachers of our children are well prepared to teach probability. Pre-service teachers' conceptions of probability are identified, and ways of helping them…

  2. Teaching Probabilities and Statistics to Preschool Children

    ERIC Educational Resources Information Center

    Pange, Jenny

    2003-01-01

    This study considers the teaching of probabilities and statistics to a group of preschool children using traditional classroom activities and Internet games. It was clear from this study that children can show a high level of understanding of probabilities and statistics, and demonstrate high performance in probability games. The use of Internet…

  3. The Cognitive Substrate of Subjective Probability

    ERIC Educational Resources Information Center

    Nilsson, Hakan; Olsson, Henrik; Juslin, Peter

    2005-01-01

    The prominent cognitive theories of probability judgment were primarily developed to explain cognitive biases rather than to account for the cognitive processes in probability judgment. In this article the authors compare 3 major theories of the processes and representations in probability judgment: the representativeness heuristic, implemented as…

  4. Spatial Probability Dynamically Modulates Visual Target Detection in Chickens

    PubMed Central

    Sridharan, Devarajan; Ramamurthy, Deepa L.; Knudsen, Eric I.

    2013-01-01

    The natural world contains a rich and ever-changing landscape of sensory information. To survive, an organism must be able to flexibly and rapidly locate the most relevant sources of information at any time. Humans and non-human primates exploit regularities in the spatial distribution of relevant stimuli (targets) to improve detection at locations of high target probability. Is the ability to flexibly modify behavior based on visual experience unique to primates? Chickens (Gallus domesticus) were trained on a multiple alternative Go/NoGo task to detect a small, briefly-flashed dot (target) in each of the quadrants of the visual field. When targets were presented with equal probability (25%) in each quadrant, chickens exhibited a distinct advantage for detecting targets at lower, relative to upper, hemifield locations. Increasing the probability of presentation in the upper hemifield locations (to 80%) dramatically improved detection performance at these locations to be on par with lower hemifield performance. Finally, detection performance in the upper hemifield changed on a rapid timescale, improving with successive target detections, and declining with successive detections at the diagonally opposite location in the lower hemifield. These data indicate the action of a process that in chickens, as in primates, flexibly and dynamically modulates detection performance based on the spatial probabilities of sensory stimuli as well as on recent performance history. PMID:23734188

  5. Factors influencing wild turkey hen survival in southcentral Iowa

    USGS Publications Warehouse

    Hubbard, M.W.; Garner, D.L.; Klaas, E.E.

    1999-01-01

    A decline in the population of eastern wild turkeys (Meleagris gallopavo silvestris) in southcentral Iowa necessitated more current estimates of population parameters. Survival of 126 eastern wild turkey hens in southcentral Iowa was investigated during 1993-96. Estimates of annual survival averaged 0.676 ?? 0.048% (x?? ?? SE) for adults and 0.713 ?? 0.125 for subadults. Mammalian predators, primarily coyotes (Canis latrans) and red fox (Vulpes fulva) accounted for 64% of all documented mortality. Age-specific annual survival distributions differed within years (P < 0.03), but no difference was detected in survival between age classes across years (P = 0.49). Based on chronological dates, survival of adult hens differed among seasons across years (P = 0.03). However, seasonal survival was not different when estimates were based on hen behavior (p = 0.48). Risk of mortality for hens increased by 2.0% for every 100-m increase in dispersal distance, decreased by 2.0% for every 10-ha increase in home range size, and decreased by 3.5% for each 1.0% increase in proportion of home range in woody cover. Although the exact cause of the population decline remains unknown, we suggest it was more likely related to a decrease in production than changes in hen survival. Declining turkey populations would likely benefit more from management designed to increase reproduction rather than hen survival.

  6. Survivability Is More Fundamental Than Evolvability

    PubMed Central

    Palmer, Michael E.; Feldman, Marcus W.

    2012-01-01

    For a lineage to survive over long time periods, it must sometimes change. This has given rise to the term evolvability, meaning the tendency to produce adaptive variation. One lineage may be superior to another in terms of its current standing variation, or it may tend to produce more adaptive variation. However, evolutionary outcomes depend on more than standing variation and produced adaptive variation: deleterious variation also matters. Evolvability, as most commonly interpreted, is not predictive of evolutionary outcomes. Here, we define a predictive measure of the evolutionary success of a lineage that we call the k-survivability, defined as the probability that the lineage avoids extinction for k generations. We estimate the k-survivability using multiple experimental replicates. Because we measure evolutionary outcomes, the initial standing variation, the full spectrum of generated variation, and the heritability of that variation are all incorporated. Survivability also accounts for the decreased joint likelihood of extinction of sub-lineages when they 1) disperse in space, or 2) diversify in lifestyle. We illustrate measurement of survivability with in silico models, and suggest that it may also be measured in vivo using multiple longitudinal replicates. The k-survivability is a metric that enables the quantitative study of, for example, the evolution of 1) mutation rates, 2) dispersal mechanisms, 3) the genotype-phenotype map, and 4) sexual reproduction, in temporally and spatially fluctuating environments. Although these disparate phenomena evolve by well-understood microevolutionary rules, they are also subject to the macroevolutionary constraint of long-term survivability. PMID:22723844

  7. Evolutionary history and distance dependence control survival of dipterocarp seedlings.

    PubMed

    Bagchi, Robert; Press, Malcolm C; Scholes, Julie D

    2010-01-01

    One important hypothesis to explain tree-species coexistence in tropical forests suggests that increased attack by natural enemies near conspecific trees gives locally rare species a competitive advantage. Host ranges of natural enemies generally encompass several closely related plant taxa suggesting that seedlings should also do poorly around adults of closely related species. We investigated the effects of adult Parashorea malaanonan on seedling survival in a Bornean rain forest. Survival of P. malaanonan seedlings was highest at intermediate distances from parent trees while heterospecific seedlings were unaffected by distance. Leaf herbivores did not drive this relationship. Survival of seedlings was lowest for P. malaanonan, and increased with phylogenetic dissimilarity from this species, suggesting that survival of close relatives of common species is reduced. This study suggests that distance dependence contributes to species coexistence and highlights the need for further investigation into the role of shared plant enemies in community dynamics. PMID:19849708

  8. Swift fox survival and production in southeastern Wyoming

    USGS Publications Warehouse

    Olson, T.L.; Lindzey, F.G.

    2002-01-01

    We estimated annual survival rates of swift foxes (Vulpes velox) and documented number of young per pair in a transition zone between shortgrass prairie and sagebrush steppe plant communities in southeastern Wyoming during 1996-2000. Annual adult survival ranged from 40% to 69%, with predation by coyotes (Canis latrans) the primary cause of deaths. Two foxes died of canine distemper virus. Annual survival rates did not differ among years (P>0.12). Nineteen of 24 (79%) swift fox pairs were observed with young over 3 years. Mean minimum litter size was 4.6 based on these 19 litters and 6 others not associated with our radiocollared foxes. Adult survival was similar and litter size slightly larger than observed elsewhere in the species range, suggesting that viable swift fox populations can be supported by sagebrush steppe and shortgrass prairie transition habitat.

  9. Optimizing nest survival and female survival: Consequences of nest site selection for Canada Geese

    USGS Publications Warehouse

    Miller, David A.; Grand, J.B.; Fondell, T.F.; Anthony, R.M.

    2007-01-01

    We examined the relationship between attributes of nest sites used by Canada Geese (Branta canadensis) in the Copper River Delta, Alaska, and patterns in nest and female survival. We aimed to determine whether nest site attributes related to nest and female survival differed and whether nest site attributes related to nest survival changed within and among years. Nest site attributes that we examined included vegetation at and surrounding the nest, as well as associations with other nesting birds. Optimal nest site characteristics were different depending on whether nest survival or female survival was examined. Prior to 25 May, the odds of daily survival for nests in tall shrubs and on islands were 2.92 and 2.26 times greater, respectively, than for nests in short shrub sites. Bald Eagles (Halieaeetus leucocephalus) are the major predator during the early breeding season and their behavior was likely important in determining this pattern. After 25 May, when eagle predation is limited due to the availability of alternative prey, no differences in nest survival among the nest site types were found. In addition, nest survival was positively related to the density of other Canada Goose nests near the nest site. Although the number of detected mortalities for females was relatively low, a clear pattern was found, with mortality three times more likely at nest sites dominated by high shrub density within 50 m than at open sites dominated by low shrub density. The negative relationship of nest concealment and adult survival is consistent with that found in other studies of ground-nesting birds. Physical barriers that limited access to nest sites by predators and sites that allowed for early detection of predators were important characteristics of nest site quality for Canada Geese and nest site quality shifted within seasons, likely as a result of shifting predator-prey interactions.

  10. Surviving atmospheric spacecraft breakup

    NASA Technical Reports Server (NTRS)

    Szewczyk, Nathaniel J.; McLamb, William

    2005-01-01

    Spacecraft travel higher and faster than aircraft, making breakup potentially less survivable. As with aircraft breakup, the dissipation of lethal forces via spacecraft breakup around an organism is likely to greatly increase the odds of survival. By employing a knowledge of space and aviation physiology, comparative physiology, and search-and-rescue techniques, we were able to correctly predict and execute the recovery of live animals following the breakup of the space shuttle Columbia. In this study, we make what is, to our knowledge, the first report of an animal, Caenorhabditis elegans, surviving the atmospheric breakup of the spacecraft that was supporting it and discuss both the lethal events these animals had to escape and the implications for search and rescue following spacecraft breakup.

  11. Survival of Tribolium confusum (Coleoptera: Tenebrionidae) in basal-casein medium supplemented with sodium selenite

    SciTech Connect

    Hogan, G.R.; Cole, B.S. )

    1988-01-01

    The trace substance selenium is known to influence several systems exhibiting a high rate of cellular proliferation. Data are reported on survival patterns and times in various developmental stages of Tribolium confusum Duval reared in a defined medium supplemented with sodium selenite. Insects reared from eggs hatching in a selenium medium (Se medium) show a prolonged time in the larval period and marked larval mortality compared with those reared on unsupplemented medium. Adults emerging in an Se medium show reduced survival compared with adults transferred to such medium 1 wk after emergence. Larval survival patterns mimic those of the adult, whereby younger larvae that are transferred to Se medium appear to be more sensitive than those exposed to Se medium later in the larval stage. Transfer of Se medium-reared adults to unsupplemented medium as pupae has a beneficial effect on survival compared with adults that emerged in Se medium 1 wk before transfer.

  12. Warm Is Better: Incubation Temperature Influences Apparent Survival and Recruitment of Wood Ducks (Aix sponsa)

    PubMed Central

    Hepp, Gary R.; Kennamer, Robert A.

    2012-01-01

    Avian parents that physically incubate their eggs must balance demands of self-maintenance with providing the proper thermal environment for egg development. Low incubation temperatures can lengthen the incubation period and produce changes in neonate phenotype that may influence subsequent survival and reproduction. We artificially incubated wood duck (Aix sponsa) eggs at three temperature regimes (low, 35.0; mid, 35.9; and high, 37.3°C) that are within the range of temperatures of naturally-incubated nests. We tested the effect of incubation temperature on duckling body composition, fledging success, the probability that females were recruited to the breeding population, and their subsequent reproductive success. Incubation period was inversely related to incubation temperature, and body mass and lipid mass for newly-hatched ducklings incubated at the lowest temperature were lower than for ducklings produced at higher temperatures. In 2008, ducklings (n = 412) were individually marked and broods (n = 38) containing ducklings from each temperature treatment were placed with wild foster mothers within 24 hrs of hatching. Ducklings incubated at the lowest temperature were less likely to fledge from nest sites than ducklings incubated at the higher temperatures. We recaptured female ducklings as adults when they were either prospecting for nest sites (n = 171; 2009–2011) or nesting (n = 527; 2009–2012). Female ducklings incubated at the lowest temperature were less likely to survive and be recruited to the breeding population than females incubated at higher temperatures. Reproductive success of surviving females also was greater for females that had been incubated at warmer temperatures. To our knowledge, this is the first avian study to link developmental conditions experienced by neonates during incubation with their survival and recruitment to the breeding population, and subsequent reproductive success. These results advance our

  13. Combined Spatio-Temporal Impacts of Climate and Longline Fisheries on the Survival of a Trans-Equatorial Marine Migrant

    PubMed Central

    Ramos, Raül; Granadeiro, José Pedro; Nevoux, Marie; Mougin, Jean-Louis; Dias, Maria Peixe; Catry, Paulo

    2012-01-01

    Predicting the impact of human activities and their derivable consequences, such as global warming or direct wildlife mortality, is increasingly relevant in our changing world. Due to their particular life history traits, long-lived migrants are amongst the most endangered and sensitive group of animals to these harming effects. Our ability to identify and quantify such anthropogenic threats in both breeding and wintering grounds is, therefore, of key importance in the field of conservation biology. Using long-term capture-recapture data (34 years, 4557 individuals) and year-round tracking data (4 years, 100 individuals) of a trans-equatorial migrant, the Cory’s shearwater (Calonectris diomedea), we investigated the impact of longline fisheries and climatic variables in both breeding and wintering areas on the most important demographic trait of this seabird, i.e. adult survival. Annual adult survival probability was estimated at 0.914±0.022 on average, declining throughout 1978–1999 but recovering during the last decade (2005–2011). Our results suggest that both the incidental bycatch associated with longline fisheries and high sea surface temperatures (indirectly linked to food availability; SST) increased mortality rates during the long breeding season (March-October). Shearwater survival was also negatively affected during the short non-breeding season (December-February) by positive episodes of the Southern Oscillation Index (SOI). Indirect negative effects of climate at both breeding (SST) and wintering grounds (SOI) had a greater impact on survival than longliner activity, and indeed these climatic factors are those which are expected to present more unfavourable trends in the future. Our work underlines the importance of considering both breeding and wintering habitats as well as precise schedules/phenology when assessing the global role of the local impacts on the dynamics of migratory species. PMID:22815833

  14. Combined spatio-temporal impacts of climate and longline fisheries on the survival of a trans-equatorial marine migrant.

    PubMed

    Ramos, Raül; Granadeiro, José Pedro; Nevoux, Marie; Mougin, Jean-Louis; Dias, Maria Peixe; Catry, Paulo

    2012-01-01

    Predicting the impact of human activities and their derivable consequences, such as global warming or direct wildlife mortality, is increasingly relevant in our changing world. Due to their particular life history traits, long-lived migrants are amongst the most endangered and sensitive group of animals to these harming effects. Our ability to identify and quantify such anthropogenic threats in both breeding and wintering grounds is, therefore, of key importance in the field of conservation biology. Using long-term capture-recapture data (34 years, 4557 individuals) and year-round tracking data (4 years, 100 individuals) of a trans-equatorial migrant, the Cory's shearwater (Calonectris diomedea), we investigated the impact of longline fisheries and climatic variables in both breeding and wintering areas on the most important demographic trait of this seabird, i.e. adult survival. Annual adult survival probability was estimated at 0.914±0.022 on average, declining throughout 1978-1999 but recovering during the last decade (2005-2011). Our results suggest that both the incidental bycatch associated with longline fisheries and high sea surface temperatures (indirectly linked to food availability; SST) increased mortality rates during the long breeding season (March-October). Shearwater survival was also negatively affected during the short non-breeding season (December-February) by positive episodes of the Southern Oscillation Index (SOI). Indirect negative effects of climate at both breeding (SST) and wintering grounds (SOI) had a greater impact on survival than longliner activity, and indeed these climatic factors are those which are expected to present more unfavourable trends in the future. Our work underlines the importance of considering both breeding and wintering habitats as well as precise schedules/phenology when assessing the global role of the local impacts on the dynamics of migratory species. PMID:22815833

  15. Survival after judicial hanging.

    PubMed

    Sabermoghaddam, Mohsen; Abad, Mohsen; Golmakani, Ebrahim; Mozaffari, Nasrollah

    2015-06-01

    Hanging is known not only as a common method of suicide but also as a capital punishment method in some countries. Although several cases have been reported to survive after the attempted suicidal/accidental hanging, to the extent of our knowledge, no modern case of survival after judicial hanging exists. We reported a case of an individual who revived after modern judicial hanging despite being declared dead. The case was admitted with poor clinical presentations and the Glasgow Coma Scale of 6/15. The victim received all the standard supportive intensive care and gained complete clinical recovery. PMID:25747958

  16. Popular Education As Adult Education within Postmodernism.

    ERIC Educational Resources Information Center

    Stanage, Sherman M.

    1995-01-01

    Adult education must become popular education in both communal and personal terms to survive funding agencies' special power-interest hegemonies, traditional higher education models, and rampant economic materialism. This article discusses six modernist constructions of adult education, highlighting professionalization and specialization, and…

  17. Adult Vaccination--A Commentary

    ERIC Educational Resources Information Center

    Logan, Jennifer

    2008-01-01

    Traditionally, vaccines have been associated with childhood. Historically, many of the most-feared communicable diseases attacked infants and toddlers, and those who survived were generally protected from those diseases as adults. During the past century tremendous advances in vaccination spared millions the morbidity and mortality associated with…

  18. Survival and breeding of polar bears in the southern Beaufort Sea in relation to sea ice

    USGS Publications Warehouse

    Regehr, E.V.; Hunter, C.M.; Caswell, H.; Amstrup, Steven C.; Stirling, I.

    2010-01-01

    1. Observed and predicted declines in Arctic sea ice have raised concerns about marine mammals. In May 2008, the US Fish and Wildlife Service listed polar bears (Ursus maritimus) - one of the most ice-dependent marine mammals - as threatened under the US Endangered Species Act. 2. We evaluated the effects of sea ice conditions on vital rates (survival and breeding probabilities) for polar bears in the southern Beaufort Sea. Although sea ice declines in this and other regions of the polar basin have been among the greatest in the Arctic, to date population-level effects of sea ice loss on polar bears have only been identified in western Hudson Bay, near the southern limit of the species' range. 3. We estimated vital rates using multistate capture-recapture models that classified individuals by sex, age and reproductive category. We used multimodel inference to evaluate a range of statistical models, all of which were structurally based on the polar bear life cycle. We estimated parameters by model averaging, and developed a parametric bootstrap procedure to quantify parameter uncertainty. 4. In the most supported models, polar bear survival declined with an increasing number of days per year that waters over the continental shelf were ice free. In 2001-2003, the ice-free period was relatively short (mean 101 days) and adult female survival was high (0 ∙ 96-0 ∙ 99, depending on reproductive state). In 2004 and 2005, the ice-free period was longer (mean 135 days) and adult female survival was low (0 ∙ 73-0 ∙ 79, depending on reproductive state). Breeding rates and cub litter survival also declined with increasing duration of the ice-free period. Confidence intervals on vital rate estimates were wide. 5. The effects of sea ice loss on polar bears in the southern Beaufort Sea may apply to polar bear populations in other portions of the polar basin that have similar sea ice dynamics and have experienced similar, or more severe, sea ice declines. Our findings

  19. Survival and breeding of polar bears in the southern Beaufort Sea in relation to sea ice.

    PubMed

    Regehr, Eric V; Hunter, Christine M; Caswell, Hal; Amstrup, Steven C; Stirling, Ian

    2010-01-01

    1. Observed and predicted declines in Arctic sea ice have raised concerns about marine mammals. In May 2008, the US Fish and Wildlife Service listed polar bears (Ursus maritimus) - one of the most ice-dependent marine mammals - as threatened under the US Endangered Species Act. 2. We evaluated the effects of sea ice conditions on vital rates (survival and breeding probabilities) for polar bears in the southern Beaufort Sea. Although sea ice declines in this and other regions of the polar basin have been among the greatest in the Arctic, to date population-level effects of sea ice loss on polar bears have only been identified in western Hudson Bay, near the southern limit of the species' range. 3. We estimated vital rates using multistate capture-recapture models that classified individuals by sex, age and reproductive category. We used multimodel inference to evaluate a range of statistical models, all of which were structurally based on the polar bear life cycle. We estimated parameters by model averaging, and developed a parametric bootstrap procedure to quantify parameter uncertainty. 4. In the most supported models, polar bear survival declined with an increasing number of days per year that waters over the continental shelf were ice free. In 2001-2003, the ice-free period was relatively short (mean 101 days) and adult female survival was high (0.96-0.99, depending on reproductive state). In 2004 and 2005, the ice-free period was longer (mean 135 days) and adult female survival was low (0.73-0.79, depending on reproductive state). Breeding rates and cub litter survival also declined with increasing duration of the ice-free period. Confidence intervals on vital rate estimates were wide. 5. The effects of sea ice loss on polar bears in the southern Beaufort Sea may apply to polar bear populations in other portions of the polar basin that have similar sea ice dynamics and have experienced similar, or more severe, sea ice declines. Our findings therefore are

  20. Bell Could Become the Copernicus of Probability

    NASA Astrophysics Data System (ADS)

    Khrennikov, Andrei

    2016-07-01

    Our aim is to emphasize the role of mathematical models in physics, especially models of geometry and probability. We briefly compare developments of geometry and probability by pointing to similarities and differences: from Euclid to Lobachevsky and from Kolmogorov to Bell. In probability, Bell could play the same role as Lobachevsky in geometry. In fact, violation of Bell’s inequality can be treated as implying the impossibility to apply the classical probability model of Kolmogorov (1933) to quantum phenomena. Thus the quantum probabilistic model (based on Born’s rule) can be considered as the concrete example of the non-Kolmogorovian model of probability, similarly to the Lobachevskian model — the first example of the non-Euclidean model of geometry. This is the “probability model” interpretation of the violation of Bell’s inequality. We also criticize the standard interpretation—an attempt to add to rigorous mathematical probability models additional elements such as (non)locality and (un)realism. Finally, we compare embeddings of non-Euclidean geometries into the Euclidean space with embeddings of the non-Kolmogorovian probabilities (in particular, quantum probability) into the Kolmogorov probability space. As an example, we consider the CHSH-test.

  1. Tracking the sensory environment: an ERP study of probability and context updating in ASD.

    PubMed

    Westerfield, Marissa A; Zinni, Marla; Vo, Khang; Townsend, Jeanne

    2015-02-01

    We recorded visual event-related brain potentials from 32 adult male participants (16 high-functioning participants diagnosed with autism spectrum disorder (ASD) and 16 control participants, ranging in age from 18 to 53 years) during a three-stimulus oddball paradigm. Target and non-target stimulus probability was varied across three probability conditions, whereas the probability of a third non-target stimulus was held constant in all conditions. P3 amplitude to target stimuli was more sensitive to probability in ASD than in typically developing participants, whereas P3 amplitude to non-target stimuli was less responsive to probability in ASD participants. This suggests that neural responses to changes in event probability are attention-dependant in high-functioning ASD. The implications of these findings for higher-level behaviors such as prediction and planning are discussed. PMID:24488156

  2. Bayesian analysis of a disability model for lung cancer survival.

    PubMed

    Armero, C; Cabras, S; Castellanos, M E; Perra, S; Quirós, A; Oruezábal, M J; Sánchez-Rubio, J

    2016-02-01

    Bayesian reasoning, survival analysis and multi-state models are used to assess survival times for Stage IV non-small-cell lung cancer patients and the evolution of the disease over time. Bayesian estimation is done using minimum informative priors for the Weibull regression survival model, leading to an automatic inferential procedure. Markov chain Monte Carlo methods have been used for approximating posterior distributions and the Bayesian information criterion has been considered for covariate selection. In particular, the posterior distribution of the transition probabilities, resulting from the multi-state model, constitutes a very interesting tool which could be useful to help oncologists and patients make efficient and effective decisions. PMID:22767866

  3. Survival of microorganisms in smectite clays - Implications for Martian exobiology

    NASA Technical Reports Server (NTRS)

    Moll, Deborah M.; Vestal, J. R.

    1992-01-01

    The survival of Baccillus subtilis, Azotobacter chroococcum, and the enteric bacteriophage MS2 has been examined in clays representing terrestrial (Wyoming type montmorillonite) and Martian (Fe3+ montmorillonite) soils exposed to terrestrial and Martian environmental conditions of temperature and atmospheric composition and pressure. An important finding is that MS2 survived simulated Mars conditions better than the terrestrial environment, probably owing to stabilization of the virus caused by the cold and dry conditions of the simulated Mars environment. This finding, the first published indication that viruses may be able to survive in Mars-type soils, may have important implications for future missions to Mars.

  4. A statistical model for red blood cell survival.

    PubMed

    Korell, Julia; Coulter, Carolyn V; Duffull, Stephen B

    2011-01-01

    A statistical model for the survival time of red blood cells (RBCs) with a continuous distribution of cell lifespans is presented. The underlying distribution of RBC lifespans is derived from a probability density function with a bathtub-shaped hazard curve, and accounts for death of RBCs due to senescence (age-dependent increasing hazard rate) and random destruction (constant hazard), as well as for death due to initial or delayed failures and neocytolysis (equivalent to early red cell mortality). The model yields survival times similar to those of previously published studies of RBC survival and is easily amenable to inclusion of drug effects and haemolytic disorders. PMID:20950630

  5. Adult Compacts.

    ERIC Educational Resources Information Center

    Further Education Unit, London (England).

    This bulletin focuses on adult compacts, three-way agreements among employers, potential employees, and trainers to provide the right kind of quality training to meet the employers' requirements. Part 1 is an executive summary of a report of the Adult Compacts Project, which studied three adult compacts in Birmingham and Loughborough, England, and…

  6. The Option for Survival

    ERIC Educational Resources Information Center

    Berry, R. Stephen

    1971-01-01

    Suggests formula for survival that takes a thermodynamic view which holds that we must recycle waste while the thermodynamic potential still is moderately high. Otherwise they are lost, as helium is lost when it leaves Earth's atmosphere and goes into space. The idea that the Earth is a closed system is a myth; it collapses each time we put our…

  7. Independence and Survival.

    ERIC Educational Resources Information Center

    James, H. Thomas

    Independent schools that are of viable size, well managed, and strategically located to meet competition will survive and prosper past the current financial crisis. We live in a complex technological society with insatiable demands for knowledgeable people to keep it running. The future will be marked by the orderly selection of qualified people,…

  8. A Profile of Survival.

    ERIC Educational Resources Information Center

    Zimrin, Hanita

    1986-01-01

    Abused children who survived the trauma of their