[Survival analysis with competing risks: estimating failure probability].

PubMed

Llorca, Javier; Delgado-Rodríguez, Miguel

2004-01-01

To show the impact of competing risks of death on survival analysis. We provide an example of survival time without chronic rejection after heart transplantation, where death before rejection acts as a competing risk. Using a computer simulation, we compare the Kaplan-Meier estimator and the multiple decrement model. The Kaplan-Meier method overestimated the probability of rejection. Next, we illustrate the use of the multiple decrement model to analyze secondary end points (in our example: death after rejection). Finally, we discuss Kaplan-Meier assumptions and why they fail in the presence of competing risks. Survival analysis should be adjusted for competing risks of death to avoid overestimation of the risk of rejection produced with the Kaplan-Meier method.

Individual-tree probability of survival model for the Northeastern United States

Treesearch

Richard M. Teck; Donald E. Hilt

1990-01-01

Describes a distance-independent individual-free probability of survival model for the Northeastern United States. Survival is predicted using a sixparameter logistic function with species-specific coefficients. Coefficients are presented for 28 species groups. The model accounts for variability in annual survival due to species, tree size, site quality, and the tree...

Interplanetary survival probability of Aspergillus terreus spores under simulated solar vacuum ultraviolet irradiation

NASA Astrophysics Data System (ADS)

Sarantopoulou, E.; Gomoiu, I.; Kollia, Z.; Cefalas, A. C.

2011-01-01

This work is a part of ESA/EU SURE project aiming to quantify the survival probability of fungal spores in space under solar irradiation in the vacuum ultraviolet (VUV) (110-180 nm) spectral region. The contribution and impact of VUV photons, vacuum, low temperature and their synergies on the survival probability of Aspergillus terreus spores is measured at simulated space conditions on Earth. To simulate the solar VUV irradiation, the spores are irradiated with a continuous discharge VUV hydrogen photon source and a molecular fluorine laser, at low and high photon intensities at 10 15 photon m -2 s -1 and 3.9×10 27 photons pulse -1 m -2 s -1, respectively. The survival probability of spores is independent from the intensity and the fluence of photons, within certain limits, in agreement with previous studies. The spores are shielded from a thin carbon layer, which is formed quickly on the external surface of the proteinaceous membrane at higher photon intensities at the start of the VUV irradiation. Extrapolating the results in space conditions, for an interplanetary direct transfer orbit from Mars to Earth, the spores will be irradiated with 3.3×10 21 solar VUV photons m -2. This photon fluence is equivalent to the irradiation of spores on Earth with 54 laser pulses with an experimental ˜92% survival probability, disregarding the contribution of space vacuum and low temperature, or to continuous solar VUV irradiation for 38 days in space near the Earth with an extrapolated ˜61% survival probability. The experimental results indicate that the damage of spores is mainly from the dehydration stress in vacuum. The high survival probability after 4 days in vacuum (˜34%) is due to the exudation of proteins on the external membrane, thus preventing further dehydration of spores. In addition, the survival probability is increasing to ˜54% at 10 K with 0.12 K/s cooling and heating rates.

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.

Survival of adult martens in Northern Wisconsin

Treesearch

Nicholas P. McCann; Patrick A. Zollner; Jonathan H. Gilbert

2010-01-01

Low adult marten (Martes americana) survival may be one factor limiting their population growth >30 yr after their reintroduction in Wisconsin, USA. We estimated annual adult marten survival at 0.81 in northern Wisconsin, with lower survival during winter (0.87) than summer-fall (1.00). Fisher (Martes pennanti) and raptor kills...

Comonotonic bounds on the survival probabilities in the Lee-Carter model for mortality projection

NASA Astrophysics Data System (ADS)

Denuit, Michel; Dhaene, Jan

2007-06-01

In the Lee-Carter framework, future survival probabilities are random variables with an intricate distribution function. In large homogeneous portfolios of life annuities, value-at-risk or conditional tail expectation of the total yearly payout of the company are approximately equal to the corresponding quantities involving random survival probabilities. This paper aims to derive some bounds in the increasing convex (or stop-loss) sense on these random survival probabilities. These bounds are obtained with the help of comonotonic upper and lower bounds on sums of correlated random variables.

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.

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.

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.

Fledgling survival increases with development time and adult survival across north and south temperate zones

USGS Publications Warehouse

Lloyd, Penn; Martin, Thomas E.

2016-01-01

Slow life histories are characterized by high adult survival and few offspring, which are thought to allow increased investment per offspring to increase juvenile survival. Consistent with this pattern, south temperate zone birds are commonly longer-lived and have fewer young than north temperate zone species. However, comparative analyses of juvenile survival, including during the first few weeks of the post-fledging period when most juvenile mortality occurs, are largely lacking. We combined our measurements of fledgling survival for eight passerines in South Africa with estimates from published studies of 57 north and south temperate zone songbird species to test three predictions: (1) fledgling survival increases with length of development time in the nest; (2) fledgling survival increases with adult survival and reduced brood size controlled for development time; and (3) south temperate zone species, with their higher adult survival and smaller brood sizes, exhibit higher fledgling survival than north temperate zone species controlled for development time. We found that fledgling survival was higher among south temperate zone species and generally increased with development time and adult survival within and between latitudinal regions. Clutch size did not explain additional variation, but was confounded with adult survival. Given the importance of age-specific mortality to life history evolution, understanding the causes of these geographical patterns of mortality is important.

An observational study: associations between nurse-reported hospital characteristics and estimated 30-day survival probabilities

PubMed Central

Tvedt, Christine; Sjetne, Ingeborg Strømseng; Helgeland, Jon; Bukholm, Geir

2014-01-01

Background There is a growing body of evidence for associations between the work environment and patient outcomes. A good work environment may maximise healthcare workers’ efforts to avoid failures and to facilitate quality care that is focused on patient safety. Several studies use nurse-reported quality measures, but it is uncertain whether these outcomes are correlated with clinical outcomes. The aim of this study was to determine the correlations between hospital-aggregated, nurse-assessed quality and safety, and estimated probabilities for 30-day survival in and out of hospital. Methods In a multicentre study involving almost all Norwegian hospitals with more than 85 beds (sample size=30, information about nurses’ perceptions of organisational characteristics were collected. Subscales from this survey were used to describe properties of the organisations: quality system, patient safety management, nurse–physician relationship, staffing adequacy, quality of nursing and patient safety. The average scores for these organisational characteristics were aggregated to hospital level, and merged with estimated probabilities for 30-day survival in and out of hospital (survival probabilities) from a national database. In this observational, ecological study, the relationships between the organisational characteristics (independent variables) and clinical outcomes (survival probabilities) were examined. Results Survival probabilities were correlated with nurse-assessed quality of nursing. Furthermore, the subjective perception of staffing adequacy was correlated with overall survival. Conclusions This study showed that perceived staffing adequacy and nurses’ assessments of quality of nursing were correlated with survival probabilities. It is suggested that the way nurses characterise the microsystems they belong to, also reflects the general performance of hospitals. PMID:24728887

A Model-Free Machine Learning Method for Risk Classification and Survival Probability Prediction.

PubMed

Geng, Yuan; Lu, Wenbin; Zhang, Hao Helen

2014-01-01

Risk classification and survival probability prediction are two major goals in survival data analysis since they play an important role in patients' risk stratification, long-term diagnosis, and treatment selection. In this article, we propose a new model-free machine learning framework for risk classification and survival probability prediction based on weighted support vector machines. The new procedure does not require any specific parametric or semiparametric model assumption on data, and is therefore capable of capturing nonlinear covariate effects. We use numerous simulation examples to demonstrate finite sample performance of the proposed method under various settings. Applications to a glioma tumor data and a breast cancer gene expression survival data are shown to illustrate the new methodology in real data analysis.

Survival probabilities of patients with childhood spinal muscle atrophy.

PubMed

Mannaa, Mohannad M; Kalra, Maninder; Wong, Brenda; Cohen, Aliza P; Amin, Raouf S

2009-03-01

Medical and technological advances over the past 2 decades have resulted in improved patient care for children with spinal muscular atrophy (SMA). The objective of the present study was to describe changes in the life expectancy of pediatric patients with SMA over time and to compare these findings with previously reported survival patterns. Medical records of all patients diagnosed with SMA over a 16-year period (1989-2005) at Cincinnati Children's Hospital Medical Center were reviewed. Data pertaining to date of birth, type of SMA, medical and surgical interventions, pulmonary complications, and date of death were obtained. Kaplan-Meier survival analyses showed a significant improvement in survival probabilities in the severest form of SMA. We found a positive trend in the survival of patients with severe SMA. Although we cannot attribute this trend to any single factor, it is likely that advances in pulmonary care and aggressive nutritional support have played a significant role.

Survival in Adult Lung Transplant Recipients Receiving Pediatric Versus Adult Donor Allografts.

PubMed

Hayes, Don; Whitson, Bryan A; Ghadiali, Samir N; Lloyd, Eric A; Tobias, Joseph D; Mansour, Heidi M; Black, Sylvester M

2015-10-01

Recent evidence showed that pediatric donor lungs increased rates of allograft failure in adult lung transplant recipients; however, the influence on survival is unclear. The United Network for Organ Sharing (UNOS) database was queried from 2005 to 2013 for adult lung transplant recipients (≥18 years) to assess survival differences among donor age categories (<18 years, 18 to 29 years, 30 to 59 years, ≥60 years). Of 12,297 adult lung transplants, 12,209 were used for univariate Cox models and Kaplan-Meier (KM) analysis and 11,602 for multivariate Cox models. A total of 1,187 adult recipients received pediatric donor lungs compared with 11,110 receiving adult donor organs. Univariate and multivariate Cox models found no difference in survival between donor ages 0 to 17 and donor ages 18 to 29, whereas donor ages 60 and older were significantly associated with increased mortality hazard, relative to the modal category of donor ages 30 to 59 (adjusted hazard ratio = 1.381; 95% confidence interval = 1.188% to 1.606%; p < 0.001). Interactions between recipient and donor age range found that the oldest donor age range was negatively associated with survival among middle-aged (30 to 59) and older (≥60) lung transplant recipients. Pediatric donor lung allografts were not negatively associated with survival in adult lung transplant recipients; however, the oldest donor age range was associated with increased mortality hazard for adult lung transplant recipients. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

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.

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.

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.

Measuring survival time: a probability-based approach useful in healthcare decision-making.

PubMed

2011-01-01

In some clinical situations, the choice between treatment options takes into account their impact on patient survival time. Due to practical constraints (such as loss to follow-up), survival time is usually estimated using a probability calculation based on data obtained in clinical studies or trials. The two techniques most commonly used to estimate survival times are the Kaplan-Meier method and the actuarial method. Despite their limitations, they provide useful information when choosing between treatment options.

Survival probability of a truncated radial oscillator subject to periodic kicks

NASA Astrophysics Data System (ADS)

Tanabe, Seiichi; Watanabe, Shinichi; Saif, Farhan; Matsuzawa, Michio

2002-03-01

Classical and quantum survival probabilities are compared for a truncated radial oscillator undergoing impulsive interactions with periodic laser pulses represented here as kicks. The system is truncated in the sense that the harmonic potential is made valid only within a finite range; the rest of the space is treated as a perfect absorber. Exploring extended values of the parameters of this model [Phys. Rev. A 63, 052721 (2001)], we supplement discussions on classical and quantum features near resonances. The classical system proves to be quasi-integrable and preserves phase-space area despite the momentum transfered by the kicks, exhibiting simple yet rich phase-space features. A geometrical argument reveals quantum-classical correspondence in the locations of minima in the paired survival probabilities while the ``ionization'' rates differ due to quantum tunneling.

Estimating the concordance probability in a survival analysis with a discrete number of risk groups.

PubMed

Heller, Glenn; Mo, Qianxing

2016-04-01

A clinical risk classification system is an important component of a treatment decision algorithm. A measure used to assess the strength of a risk classification system is discrimination, and when the outcome is survival time, the most commonly applied global measure of discrimination is the concordance probability. The concordance probability represents the pairwise probability of lower patient risk given longer survival time. The c-index and the concordance probability estimate have been used to estimate the concordance probability when patient-specific risk scores are continuous. In the current paper, the concordance probability estimate and an inverse probability censoring weighted c-index are modified to account for discrete risk scores. Simulations are generated to assess the finite sample properties of the concordance probability estimate and the weighted c-index. An application of these measures of discriminatory power to a metastatic prostate cancer risk classification system is examined.

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

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.

Chronic exposure to dim artificial light at night decreases fecundity and adult survival in Drosophila melanogaster.

PubMed

McLay, L K; Green, M P; Jones, T M

2017-07-01

The presence of artificial light at night is expanding in geographical range and increasing in intensity to such an extent that species living in urban environments may never experience natural darkness. The negative ecological consequences of artificial night lighting have been identified in several key life history traits across multiple taxa (albeit with a strong vertebrate focus); comparable data for invertebrates is lacking. In this study, we explored the effect of chronic exposure to different night-time lighting intensities on growth, reproduction and survival in Drosophila melanogaster. We reared three generations of flies under identical daytime light conditions (2600lx) and one of four ecologically relevant ALAN treatments (0, 1, 10 or 100lx), then explored variation in oviposition, number of eggs produced, juvenile growth and survival and adult survival. We found that, in the presence of light at night (1, 10 and 100lx treatments), the probability of a female commencing oviposition and the number of eggs laid was significantly reduced. This did not translate into differences at the juvenile phase: juvenile development times and the probability of eclosing as an adult were comparable across all treatments. However, we demonstrate for the first time a direct link between chronic exposure to light at night (greater than 1lx) and adult survival. Our data highlight that ALAN has the capacity to cause dramatic shifts in multiple life history traits at both the individual and population level. Such shifts are likely to be species-specific, however a more in depth understanding of the broad-scale impact of ALAN and the relevant mechanisms driving biological change is urgently required as we move into an increasing brightly lit future. Copyright © 2017 Elsevier Ltd. All rights reserved.

[WebSurvCa: web-based estimation of death and survival probabilities in a cohort].

PubMed

Clèries, Ramon; Ameijide, Alberto; Buxó, Maria; Vilardell, Mireia; Martínez, José Miguel; Alarcón, Francisco; Cordero, David; Díez-Villanueva, Ana; Yasui, Yutaka; Marcos-Gragera, Rafael; Vilardell, Maria Loreto; Carulla, Marià; Galceran, Jaume; Izquierdo, Ángel; Moreno, Víctor; Borràs, Josep M

2018-01-19

Relative survival has been used as a measure of the temporal evolution of the excess risk of death of a cohort of patients diagnosed with cancer, taking into account the mortality of a reference population. Once the excess risk of death has been estimated, three probabilities can be computed at time T: 1) the crude probability of death associated with the cause of initial diagnosis (disease under study), 2) the crude probability of death associated with other causes, and 3) the probability of absolute survival in the cohort at time T. This paper presents the WebSurvCa application (https://shiny.snpstats.net/WebSurvCa/), whereby hospital-based and population-based cancer registries and registries of other diseases can estimate such probabilities in their cohorts by selecting the mortality of the relevant region (reference population). Copyright © 2017 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

Estimating stage-specific daily survival probabilities of nests when nest age is unknown

USGS Publications Warehouse

Stanley, T.R.

2004-01-01

Estimation of daily survival probabilities of nests is common in studies of avian populations. Since the introduction of Mayfield's (1961, 1975) estimator, numerous models have been developed to relax Mayfield's assumptions and account for biologically important sources of variation. Stanley (2000) presented a model for estimating stage-specific (e.g. incubation stage, nestling stage) daily survival probabilities of nests that conditions on “nest type” and requires that nests be aged when they are found. Because aging nests typically requires handling the eggs, there may be situations where nests can not or should not be aged and the Stanley (2000) model will be inapplicable. Here, I present a model for estimating stage-specific daily survival probabilities that conditions on nest stage for active nests, thereby obviating the need to age nests when they are found. Specifically, I derive the maximum likelihood function for the model, evaluate the model's performance using Monte Carlo simulations, and provide software for estimating parameters (along with an example). For sample sizes as low as 50 nests, bias was small and confidence interval coverage was close to the nominal rate, especially when a reduced-parameter model was used for estimation.

Fingerprints of exceptional points in the survival probability of resonances in atomic spectra

NASA Astrophysics Data System (ADS)

Cartarius, Holger; Moiseyev, Nimrod

2011-07-01

The unique time signature of the survival probability exactly at the exceptional point parameters is studied here for the hydrogen atom in strong static magnetic and electric fields. We show that indeed the survival probability S(t)=|<ψ(0)|ψ(t)>|2 decays exactly as |1-at|2e-ΓEPt/ℏ, where ΓEP is associated with the decay rate at the exceptional point and a is a complex constant depending solely on the initial wave packet that populates exclusively the two almost degenerate states of the non-Hermitian Hamiltonian. This may open the possibility for a first experimental detection of exceptional points in a quantum system.

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.; 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

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.

Seasonal survival of adult female mottled ducks

USGS Publications Warehouse

Moon, Jena A.; Haukos, David A.; Conway, Warren C.

2017-01-01

The mottled duck (Anas fulgivula) is a non-migratory duck dependent on coastal habitats to meet all of its life cycle requirements in the Western Gulf Coast (WGC) of Texas and Louisiana, USA. This population of mottled ducks has experienced a moderate decline during the past 2 decades. Adult survival has been identified as an important factor influencing population demography. Previous work based on band-recovery data has provided only annual estimates of survival. We assessed seasonal patterns of female mottled duck survival from 2009 to 2012 using individuals marked with satellite platform transmitter terminals (PTTs). We used temperature and movement sensors within each PTT to indicate potential mortality events. We estimated cumulative weekly survival and ranked factors influential in patterns of mortality using known-fate modeling in Program MARK. Models included 4 predictors: week; hunting and non-hunting periods; biological periods defined as breeding, brooding, molt, and pairing; and mass at time of capture. Models containing hunt periods, during and outside the mottled duck season, comprised essentially 100% of model weights where both legal and illegal harvest had a negative influence on mottled duck survival. Survival rates were low during 2009–2011 (12–38% annual rate of survival), when compared with the long-term banding average of 53% annual survival. During 2011, survival of female mottled ducks was the lowest annual rate (12%) ever documented and coincided with extreme drought. Management actions maximizing the availability of wetlands and associated upland habitats during hunting seasons and drought conditions may increase adult female mottled duck survival.

Prediction of Conditional Probability of Survival After Surgery for Gastric Cancer: A Study Based on Eastern and Western Large Data Sets.

PubMed

Zhong, Qing; Chen, Qi-Yue; Li, Ping; Xie, Jian-Wei; Wang, Jia-Bin; Lin, Jian-Xian; Lu, Jun; Cao, Long-Long; Lin, Mi; Tu, Ru-Hong; Zheng, Chao-Hui; Huang, Chang-Ming

2018-04-20

The dynamic prognosis of patients who have undergone curative surgery for gastric cancer has yet to be reported. Our objective was to devise an accurate tool for predicting the conditional probability of survival for these patients. We analyzed 11,551 gastric cancer patients from the Surveillance, Epidemiology, and End Results database. Two-thirds of the patients were selected randomly for the development set and one-third for the validation set. Two nomograms were constructed to predict the conditional probability of overall survival and the conditional probability of disease-specific survival, using conditional survival methods. We then applied these nomograms to the 4,001 patients in the database from Fujian Medical University Union Hospital, Fuzhou, China, one of the most active Chinese institutes. The 5-year conditional probability of overall survival of the patients was 41.6% immediately after resection and increased to 52.8%, 68.2%, and 80.4% at 1, 2, and 3 years after gastrectomy. The 5-year conditional probability of disease-specific survival "increased" from 48.9% at the time of gastrectomy to 59.8%, 74.7%, and 85.5% for patients surviving 1, 2, and 3 years, respectively. Sex; race; age; depth of tumor invasion; lymph node metastasis; and tumor size, site, and grade were associated with overall survival and disease-specific survival (P <.05). Within the Surveillance, Epidemiology, and End Results validation set, the accuracy of the conditional probability of overall survival nomogram was 0.77, 0.81, 0.82, and 0.82 at 1, 3, 5, and 10 years after gastrectomy, respectively. Within the other validation set from the Fujian Medical University Union Hospital (n = 4,001), the accuracy of the conditional probability of overall survival nomogram was 0.76, 0.79, 0.77, and 0.77 at 1, 3, 5, and 10 years, respectively. The accuracy of the conditional probability of disease-specific survival model was also favorable. The calibration curve demonstrated good agreement

COUNTRY-LEVEL SOCIOECONOMIC INDICATORS ASSOCIATED WITH SURVIVAL PROBABILITY OF BECOMING A CENTENARIAN AMONG OLDER EUROPEAN ADULTS: GENDER INEQUALITY, MALE LABOUR FORCE PARTICIPATION AND PROPORTIONS OF WOMEN IN PARLIAMENTS.

PubMed

Kim, Jong In; Kim, Gukbin

2017-03-01

This study confirms an association between survival probability of becoming a centenarian (SPBC) for those aged 65 to 69 and country-level socioeconomic indicators in Europe: the gender inequality index (GII), male labour force participation (MLP) rates and proportions of seats held by women in national parliaments (PWP). The analysis was based on SPBC data from 34 countries obtained from the United Nations (UN). Country-level socioeconomic indicator data were obtained from the UN and World Bank databases. The associations between socioeconomic indicators and SPBC were assessed using correlation coefficients and multivariate regression models. The findings show significant correlations between the SPBC for women and men aged 65 to 69 and country-level socioeconomic indicators: GII (r=-0.674, p=0.001), MLP (r=0.514, p=0.002) and PWP (r=0.498, p=0.003). The SPBC predictors for women and men were lower GIIs and higher MLP and PWP (R 2=0.508, p=0.001). Country-level socioeconomic indicators appear to have an important effect on the probability of becoming a centenarian in European adults aged 65 to 69. Country-level gender equality policies in European counties may decrease the risk of unhealthy old age and increase longevity in elders through greater national gender equality; disparities in GII and other country-level socioeconomic indicators impact longevity probability. National longevity strategies should target country-level gender inequality.

Effect of drift on the temporal asymptotic form of the particle survival probability in media with absorbing traps

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arkhincheev, V. E., E-mail: varkhin@mail.ru

A new asymptotic form of the particle survival probability in media with absorbing traps has been established. It is shown that this drift mechanism determines a new temporal behavior of the probability of particle survival in media with absorbing traps over long time intervals.

Postrelease movements and survival of adult and young black-footed ferrets

USGS Publications Warehouse

Biggins, Dean E.; Godbey, Jerry L.; Livieri, Travis M.; Matchett, Marc R.; Bibles, Brent D.

2006-01-01

A successful captive breeding program for highly endangered black-footed ferrets (Mustela nigripes) has resulted in surplus animals that have been released at multiple sites since 1991. Because reproductive output of captive ferrets declines after several years, many adult ferrets must be removed from captive breeding facilities annually to keep total production high. Adults are routinely released, with young-of-the-year, on prairie dog (Cynomys spp.) colonies. We evaluated postrelease movements and survival rates for 94 radio-tagged young and adult ferrets. Radio-tagged adult ferrets made longer movements than young ferrets during the night of release and had significantly lower survival rates for the first 14 days. Coyotes (Canis latrans) caused the largest number of ferret losses. A larger data set of 623 ferrets represented adults and young that were individually marked with passive integrated transponders but were not radio tagged. Minimum survival rates, calculated primarily from ferrets detected during spotlight searches and identified with tag readers, again were significantly lower for adults than for young ferrets at 30 days postrelease (10.1 percent and 45.5 percent survival, respectively) and at 150 days postrelease (5.7 percent and 25.9 percent). Assessment of known survival time by using linear modeling demonstrated a significant interaction between age and sex, with greater disparity between adults and kits for females than for males. Postrelease survival of adult ferrets might be increased if animals were given earlier and longer exposure to the quasinatural environments of preconditioning pens. 

Lesser scaup breeding probability and female survival on the yukon flats, Alaska

USGS Publications Warehouse

Martin, K.H.; Lindberg, M.S.; Schmutz, J.A.; Bertram, M.R.

2009-01-01

Information on the ecology of waterfowl breeding in the boreal forest is lacking, despite the boreal region's importance to continental waterfowl populations and to duck species that are currently declining, such as lesser scaup (Aythya affinis). We estimated breeding probability and breeding season survival of female lesser scaup on the Yukon Flats National Wildlife Refuge, Alaska, USA, in 2005 and 2006. We captured and marked 93 lesser scaup with radiotransmitters during prelaying and nesting periods. Although all marked lesser scaup females were paired throughout prelaying and incubation periods, we estimated breeding probability over both years as 0.12 (SE = 0.05, n = 67) using telemetry. Proportion of lesser scaup females undergoing rapid follicle growth at capture in 2006 was 0.46 (SE = 0.11, n = 37), based on concentration of yolk precursors in blood plasma. By combining methods based on telemetry, yolk precursors, and postovulatory follicles, we estimated maximum breeding probability as 0.68 (SE = 0.08, n = 37) in 2006. Notably, breeding probability was positively related to female body mass. Survival of female lesser scaup during the nesting and brood-rearing periods was 0.92 (SE = 0.05) in 2005 and 0.86 (SE = 0.08) in 2006. Our results suggest that breeding probability is lower than expected for lesser scaup. In addition, the implicit assumption of continental duck-monitoring programs that all paired females attempt to breed should be reevaluated. Recruitment estimates based on annual breeding-pair surveys may overestimate productivity of scaup pairs in the boreal forest. ?? The Wildlife Society.

Reproduction, preweaning survival, and survival of adult sea otters at Kodiak Island, Alaska

USGS Publications Warehouse

Monson, Daniel H.; DeGange, Anthony R.

1995-01-01

Radiotelemetry methods were used to examine the demographic characteristics of sea otters inhabiting the leading edge of an expanding population on Kodiak Island, Alaska. Fifteen male and 30 female sea otters were instrumented and followed from 1986 to 1990. Twenty-one percent of females were sexually mature (had pupped) at age 2, 57% by age 3, 88% by age 4, and 100% by age 5. Fifteen females produced 26 pups, an overall reproduction rate of 94% for mature females. The reproduction rate was 17, 45, 66, and 100% for 2-, 3-, 4-, and 5-year-olds, respectively. Eighty-five percent of observed pups survived to weaning (120 days), and the percentage of pups weaned ranged from 34% for pups of 2-year-olds to 100% for pups of 5-year-olds. At least three of four known pup losses occurred within a month of parturition. The mean pup dependency period for weaned pups was 153 days and the mean gestation period was 218 days. No synchrony in pupping activity was observed. Mean annual survival of adults was high. Estimates of survival ranged from 89 to 96% for females and 86 to 91% for males. Human harvest was the primary source of known mortality of adults. Our estimates of reproductive rates and survival of adults are at the high end of those reported for sea otters, but preweaning survival stands out as being particularly high. Abundant food resources and the availability of protected water presumably contributed to the high reproductive success observed in this recently established sea otter population.

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.

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.

Cross-species prediction of human survival probabilities for accelerated anthrax vaccine absorbed (AVA) regimens and the potential for vaccine and antibiotic dose sparing.

PubMed

Stark, G V; Sivko, G S; VanRaden, M; Schiffer, J; Taylor, K L; Hewitt, J A; Quinn, C P; Nuzum, E O

2016-12-12

Anthrax vaccine adsorbed (AVA, BioThrax) was recently approved by the Food and Drug Administration (FDA) for a post-exposure prophylaxis (PEP) indication in adults 18-65years of age. The schedule is three doses administered subcutaneous (SC) at 2-week intervals (0, 2, and 4weeks), in conjunction with a 60-day course of antimicrobials. The Public Health Emergency Medical Countermeasures Enterprise (PHEMCE) developed an animal model to support assessment of a shortened antimicrobial PEP duration following Bacillus anthracis exposure. A nonhuman primate (NHP) study was completed to evaluate the efficacy of a two dose anthrax vaccine absorbed (AVA) schedule (0, 2weeks) aerosol challenged with high levels of B. anthracis spores at week4- the time point at which humans would receive the third vaccination of the approved PEP schedule. Here we use logistic regression models to combine the survival data from the NHP study along with serum anthrax lethal toxin neutralizing activity (TNA) and anti-PA IgG measured by enzyme linked immunosorbent assay (ELISA) data to perform a cross-species analysis to estimate survival probabilities in vaccinated human populations at this time interval (week4 of the PEP schedule). The bridging analysis demonstrated that high levels of NHP protection also yield high predicted probability of human survival just 2weeks after the second dose of vaccine with the full or half antigen dose regimen. The absolute difference in probability of human survival between the full and half antigen dose was estimated to be at most approximately 20%, indicating that more investigation of the half-antigen dose for vaccine dose sparing strategies may be warranted. Copyright © 2016 Elsevier Ltd. All rights reserved.

Survival Analysis and Actuarial Parameters of Sternechus subsignatus (Coleoptera: Curculionidae) Adults.

PubMed

Guillermina Socías, María; Van Nieuwenhove, Guido; Murúa, María Gabriela; Willink, Eduardo; Liljesthröm, Gerardo Gustavo

2016-04-01

The soybean stalk weevil, Sternechus subsignatus Boheman 1836 (Coleoptera: Curculionidae), is a very serious soybean pest in the Neotropical region. Both adults and larvae feed on soybean, causing significant yield losses. Adult survival was evaluated during three soybean growing seasons under controlled environmental conditions. A survival analysis was performed using a parametric survival fit approach in order to generate survival curves and obtain information that could help optimize integrated management strategies for this weevil pest. Sex of the weevils, crop season, fortnight in which weevils emerged, and their interaction were studied regarding their effect on adult survival. The results showed that females lived longer than males, but both genders were actually long-lived, reaching 224 and 176 d, respectively. Mean lifetime (l50) was 121.88±4.56 d for females and 89.58±2.72 d for males. Although variations were observed in adult longevities among emergence fortnights and soybean seasons, only in December and January fortnights of the 2007–2008 season and December fortnights of 2009–2010 did the statistically longest and shortest longevities occur, respectively. Survivorship data (lx) of adult females and males were fitted to the Weibull frequency distribution model. The survival curve was type I for both sexes, which indicated that mortality corresponded mostly to old individuals.

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

PubMed

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

2016-11-01

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. 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. 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. 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. © The Author(s) 2013.

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.

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

Technical report. The application of probability-generating functions to linear-quadratic radiation survival curves.

PubMed

Kendal, W S

2000-04-01

To illustrate how probability-generating functions (PGFs) can be employed to derive a simple probabilistic model for clonogenic survival after exposure to ionizing irradiation. Both repairable and irreparable radiation damage to DNA were assumed to occur by independent (Poisson) processes, at intensities proportional to the irradiation dose. Also, repairable damage was assumed to be either repaired or further (lethally) injured according to a third (Bernoulli) process, with the probability of lethal conversion being directly proportional to dose. Using the algebra of PGFs, these three processes were combined to yield a composite PGF that described the distribution of lethal DNA lesions in irradiated cells. The composite PGF characterized a Poisson distribution with mean, chiD+betaD2, where D was dose and alpha and beta were radiobiological constants. This distribution yielded the conventional linear-quadratic survival equation. To test the composite model, the derived distribution was used to predict the frequencies of multiple chromosomal aberrations in irradiated human lymphocytes. The predictions agreed well with observation. This probabilistic model was consistent with single-hit mechanisms, but it was not consistent with binary misrepair mechanisms. A stochastic model for radiation survival has been constructed from elementary PGFs that exactly yields the linear-quadratic relationship. This approach can be used to investigate other simple probabilistic survival models.

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.

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.

Conditional survival of pediatric, adolescent, and young adult soft tissue sarcoma and bone tumor patients.

PubMed

Ou, Judy Y; Spraker-Perlman, Holly; Dietz, Andrew C; Smits-Seemann, Rochelle R; Kaul, Sapna; Kirchhoff, Anne C

2017-10-01

Survival estimates for soft tissue sarcomas (STS) and malignant bone tumors (BT) diagnosed in pediatric, adolescent, and young adult patients are not easily available. We present survival estimates based on a patient having survived a defined period of time (conditional survival). Conditional survival estimates for the short-term were calculated for patients from diagnosis to the first five years after diagnosis and for patients surviving in the long-term (up to 20 years after diagnosis). We identified 703 patients who were diagnosed with a STS or BT at age ≤25 years from January 1, 1986 to December 31, 2012 at a large pediatric oncology center in Salt Lake City, Utah, United States. We obtained cancer type, age at diagnosis, primary site, and demographic data from medical records, and vital status through the National Death Index. Cancer stage was available for a subset of the cohort through the Utah Cancer Registry. Cox proportional hazards models, adjusted for age and sex, calculated survival estimates for all analyses. Short-term survival improves over time for both sarcomas. Short-term survival for STS from diagnosis (Year 0) did not differ by sex, but short-term survival starting from 1-year post diagnosis was significantly worse for male patients (Survival probability 1-year post-diagnosis [SP1]:77% [95% CI:71-83]) than female patients (SP1:86% [81-92]). Survival for patients who were diagnosed at age ≤10 years (Survival probability at diagnosis [SP0]:85% [79-91]) compared to diagnosis at ages 16-25 years (SP0:67% [59-75]) was significantly better at all time-points from diagnosis to 5-years post-diagnosis. Survival for axial sites (SP0:69% [63-75]) compared to extremities (SP0:84% [79-90]) was significantly worse from diagnosis to 1-year post-diagnosis. Survival for axial BT (SP0: 64% [54-74] was significantly worse than BT in the extremities (SP0:73% [68-79]) from diagnosis to 3-years post diagnosis. Relapsed patients of both sarcoma types had

The two-parametric scaling and new temporal asymptotic of survival probability of diffusing particle in the medium with traps.

PubMed

Arkhincheev, V E

2017-03-01

The new asymptotic behavior of the survival probability of particles in a medium with absorbing traps in an electric field has been established in two ways-by using the scaling approach and by the direct solution of the diffusion equation in the field. It has shown that at long times, this drift mechanism leads to a new temporal behavior of the survival probability of particles in a medium with absorbing traps.

The two-parametric scaling and new temporal asymptotic of survival probability of diffusing particle in the medium with traps

NASA Astrophysics Data System (ADS)

Arkhincheev, V. E.

2017-03-01

The new asymptotic behavior of the survival probability of particles in a medium with absorbing traps in an electric field has been established in two ways—by using the scaling approach and by the direct solution of the diffusion equation in the field. It has shown that at long times, this drift mechanism leads to a new temporal behavior of the survival probability of particles in a medium with absorbing traps.

How the probability of presentation to a primary care clinician correlates with cancer survival rates: a European survey using vignettes.

PubMed

Harris, Michael; Frey, Peter; Esteva, Magdalena; Gašparović Babić, Svjetlana; Marzo-Castillejo, Mercè; Petek, Davorina; Petek Ster, Marija; Thulesius, Hans

2017-03-01

European cancer survival rates vary widely. System factors, including whether or not primary care physicians (PCPs) are gatekeepers, may account for some of these differences. This study explores where patients who may have cancer are likely to present for medical care in different European countries, and how probability of presentation to a primary care clinician correlates with cancer survival rates. Seventy-eight PCPs in a range of European countries assessed four vignettes representing patients who might have cancer, and consensus groups agreed how likely those patients were to present to different clinicians in their own countries. These data were compared with national cancer survival rates. A total of 14 countries. Consensus groups of PCPs. Probability of initial presentation to a PCP for four clinical vignettes. There was no significant correlation between overall national 1-year relative cancer survival rates and the probability of initial presentation to a PCP (r  = -0.16, 95% CI -0.39 to 0.08). Within that there was large variation depending on the type of cancer, with a significantly poorer lung cancer survival in countries where patients were more likely to initially consult a PCP (lung r = -0.57, 95% CI -0.83 to -0.12; ovary: r = -0.13, 95% CI -0.57 to 0.38; breast r = 0.14, 95% CI -0.36 to 0.58; bowel: r = 0.20, 95% CI -0.31 to 0.62). There were wide variations in the degree of gatekeeping between countries, with no simple binary model as to whether or not a country has a "PCP-as-gatekeeper" system. While there was case-by-case variation, there was no overall evidence of a link between a higher probability of initial consultation with a PCP and poorer cancer survival. KEY POINTS European cancer survival rates vary widely, and health system factors may account for some of these differences. The data from 14 European countries show a wide variation in the probability of initial presentation to a PCP. The degree to

The Effects of Phonotactic Probability and Neighborhood Density on Adults' Word Learning in Noisy Conditions

PubMed Central

Storkel, Holly L.; Lee, Jaehoon; Cox, Casey

2016-01-01

Purpose Noisy conditions make auditory processing difficult. This study explores whether noisy conditions influence the effects of phonotactic probability (the likelihood of occurrence of a sound sequence) and neighborhood density (phonological similarity among words) on adults' word learning. Method Fifty-eight adults learned nonwords varying in phonotactic probability and neighborhood density in either an unfavorable (0-dB signal-to-noise ratio [SNR]) or a favorable (+8-dB SNR) listening condition. Word learning was assessed using a picture naming task by scoring the proportion of phonemes named correctly. Results The unfavorable 0-dB SNR condition showed a significant interaction between phonotactic probability and neighborhood density in the absence of main effects. In particular, adults learned more words when phonotactic probability and neighborhood density were both low or both high. The +8-dB SNR condition did not show this interaction. These results are inconsistent with those from a prior adult word learning study conducted under quiet listening conditions that showed main effects of word characteristics. Conclusions As the listening condition worsens, adult word learning benefits from a convergence of phonotactic probability and neighborhood density. Clinical implications are discussed for potential populations who experience difficulty with auditory perception or processing, making them more vulnerable to noise. PMID:27788276

The Effects of Phonotactic Probability and Neighborhood Density on Adults' Word Learning in Noisy Conditions.

PubMed

Han, Min Kyung; Storkel, Holly L; Lee, Jaehoon; Cox, Casey

2016-11-01

Noisy conditions make auditory processing difficult. This study explores whether noisy conditions influence the effects of phonotactic probability (the likelihood of occurrence of a sound sequence) and neighborhood density (phonological similarity among words) on adults' word learning. Fifty-eight adults learned nonwords varying in phonotactic probability and neighborhood density in either an unfavorable (0-dB signal-to-noise ratio [SNR]) or a favorable (+8-dB SNR) listening condition. Word learning was assessed using a picture naming task by scoring the proportion of phonemes named correctly. The unfavorable 0-dB SNR condition showed a significant interaction between phonotactic probability and neighborhood density in the absence of main effects. In particular, adults learned more words when phonotactic probability and neighborhood density were both low or both high. The +8-dB SNR condition did not show this interaction. These results are inconsistent with those from a prior adult word learning study conducted under quiet listening conditions that showed main effects of word characteristics. As the listening condition worsens, adult word learning benefits from a convergence of phonotactic probability and neighborhood density. Clinical implications are discussed for potential populations who experience difficulty with auditory perception or processing, making them more vulnerable to noise.

Temperature during larval development and adult maintenance influences the survival of Anopheles gambiae s.s.

PubMed

Christiansen-Jucht, Céline; Parham, Paul E; Saddler, Adam; Koella, Jacob C; Basáñez, María-Gloria

2014-11-05

Malaria transmission depends on vector life-history parameters and population dynamics, and particularly on the survival of adult Anopheles mosquitoes. These dynamics are sensitive to climatic and environmental factors, and temperature is a particularly important driver. Data currently exist on the influence of constant and fluctuating adult environmental temperature on adult Anopheles gambiae s.s. survival and on the effect of larval environmental temperature on larval survival, but none on how larval temperature affects adult life-history parameters. Mosquito larvae and pupae were reared individually at different temperatures (23 ± 1°C, 27 ± 1°C, 31 ± 1°C, and 35 ± 1°C), 75 ± 5% relative humidity. Upon emergence into imagoes, individual adult females were either left at their larval temperature or placed at a different temperature within the range above. Survival was monitored every 24 hours and data were analysed using non-parametric and parametric methods. The Gompertz distribution fitted the survivorship data better than the gamma, Weibull, and exponential distributions overall and was adopted to describe mosquito mortality rates. Increasing environmental temperature during the larval stages decreased larval survival (p < 0.001). Increases of 4°C (from 23°C to 27°C, 27°C to 31°C, and 31°C to 35°C), 8°C (27°C to 35°C) and 12°C (23°C to 35°C) statistically significantly increased larval mortality (p < 0.001). Higher environmental temperature during the adult stages significantly lowered adult survival overall (p < 0.001), with increases of 4°C and 8°C significantly influencing survival (p < 0.001). Increasing the larval environment temperature also significantly increased adult mortality overall (p < 0.001): a 4°C increase (23°C to 27°C) did not significantly affect adult survival (p > 0.05), but an 8°C increase did (p < 0.05). The effect of a 4°C increase in larval temperature from 27

Cultural Differences in Young Adults' Perceptions of the Probability of Future Family Life Events.

PubMed

Speirs, Calandra; Huang, Vivian; Konnert, Candace

2017-09-01

Most young adults are exposed to family caregiving; however, little is known about their perceptions of their future caregiving activities such as the probability of becoming a caregiver for their parents or providing assistance in relocating to a nursing home. This study examined the perceived probability of these events among 182 young adults and the following predictors of their probability ratings: gender, ethnicity, work or volunteer experience, experiences with caregiving and nursing homes, expectations about these transitions, and filial piety. Results indicated that Asian or South Asian participants rated the probability of being a caregiver as significantly higher than Caucasian participants, and the probability of placing a parent in a nursing home as significantly lower. Filial piety was the strongest predictor of the probability of these life events, and it mediated the relationship between ethnicity and probability ratings. These findings indicate the significant role of filial piety in shaping perceptions of future life events.

Gender, literacy, and survival among Ethiopian adults, 1987 - 96.

PubMed Central

Berhane, Yemane; Hogberg, Ulf; Byass, Peter; Wall, Stig

2002-01-01

OBJECTIVE: To examine relationships between gender, literacy and survival among adults in Meskan and Mareko district, Ethiopia. METHODS: On the basis of an established demographic surveillance system, an open-cohort analysis of 172726 person-years covering the period January 1987 to December 1996 was conducted in 10 randomly selected local communities. FINDINGS: The crude mortality rate was 11.2 per 1000 person-years among adults aged > or =15 years; the values for males and females were 11.9 and 10.6 per 1000 person-years, respectively. Kaplan - Meier estimates showed that literacy and being female were both favourable for survival throughout adulthood. Cox's regression models showed that age, gender, literacy and area (rural lowland, rural highland and urban) were significant factors in survival: younger, female, literate urban dwellers were the most favoured. Gender differences in mortality were small in the rural areas, possibly because of the harsh living conditions and the marginalization of women. Literacy was a more significant factor for survival in the rural areas, where mortality was highest, while gender was more important in the one urban area studied. The levels of literacy were lowest among rural females. CONCLUSION: Special attention should be given to raising literacy levels among rural women with a view to improving their survival. PMID:12378289

Modeling spatial variation in avian survival and residency probabilities

USGS Publications Warehouse

Saracco, James F.; Royle, J. Andrew; DeSante, David F.; Gardner, Beth

2010-01-01

The importance of understanding spatial variation in processes driving animal population dynamics is widely recognized. Yet little attention has been paid to spatial modeling of vital rates. Here we describe a hierarchical spatial autoregressive model to provide spatially explicit year-specific estimates of apparent survival (phi) and residency (pi) probabilities from capture-recapture data. We apply the model to data collected on a declining bird species, Wood Thrush (Hylocichla mustelina), as part of a broad-scale bird-banding network, the Monitoring Avian Productivity and Survivorship (MAPS) program. The Wood Thrush analysis showed variability in both phi and pi among years and across space. Spatial heterogeneity in residency probability was particularly striking, suggesting the importance of understanding the role of transients in local populations. We found broad-scale spatial patterning in Wood Thrush phi and pi that lend insight into population trends and can direct conservation and research. The spatial model developed here represents a significant advance over approaches to investigating spatial pattern in vital rates that aggregate data at coarse spatial scales and do not explicitly incorporate spatial information in the model. Further development and application of hierarchical capture-recapture models offers the opportunity to more fully investigate spatiotemporal variation in the processes that drive population changes.

How the probability of presentation to a primary care clinician correlates with cancer survival rates: a European survey using vignettes

PubMed Central

Harris, Michael; Frey, Peter; Esteva, Magdalena; Gašparović Babić, Svjetlana; Marzo-Castillejo, Mercè; Petek, Davorina; Petek Ster, Marija; Thulesius, Hans

2017-01-01

Objective European cancer survival rates vary widely. System factors, including whether or not primary care physicians (PCPs) are gatekeepers, may account for some of these differences. This study explores where patients who may have cancer are likely to present for medical care in different European countries, and how probability of presentation to a primary care clinician correlates with cancer survival rates. Design Seventy-eight PCPs in a range of European countries assessed four vignettes representing patients who might have cancer, and consensus groups agreed how likely those patients were to present to different clinicians in their own countries. These data were compared with national cancer survival rates. Setting A total of 14 countries. Subjects Consensus groups of PCPs. Main outcome measures Probability of initial presentation to a PCP for four clinical vignettes. Results There was no significant correlation between overall national 1-year relative cancer survival rates and the probability of initial presentation to a PCP (r  = −0.16, 95% CI −0.39 to 0.08). Within that there was large variation depending on the type of cancer, with a significantly poorer lung cancer survival in countries where patients were more likely to initially consult a PCP (lung r = −0.57, 95% CI −0.83 to −0.12; ovary: r = −0.13, 95% CI −0.57 to 0.38; breast r = 0.14, 95% CI −0.36 to 0.58; bowel: r = 0.20, 95% CI −0.31 to 0.62). Conclusions There were wide variations in the degree of gatekeeping between countries, with no simple binary model as to whether or not a country has a “PCP-as-gatekeeper” system. While there was case-by-case variation, there was no overall evidence of a link between a higher probability of initial consultation with a PCP and poorer cancer survival. Key points European cancer survival rates vary widely, and health system factors may account for some of these differences. The data from 14 European

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.

Adjuvant chemotherapy and overall survival in adult medulloblastoma.

PubMed

Kann, Benjamin H; Lester-Coll, Nataniel H; Park, Henry S; Yeboa, Debra N; Kelly, Jacqueline R; Baehring, Joachim M; Becker, Kevin P; Yu, James B; Bindra, Ranjit S; Roberts, Kenneth B

2017-02-01

Although chemotherapy is used routinely in pediatric medulloblastoma (MB) patients, its benefit for adult MB is unclear. We evaluated the survival impact of adjuvant chemotherapy in adult MB. Using the National Cancer Data Base, we identified patients aged 18 years and older who were diagnosed with MB in 2004-2012 and underwent surgical resection and adjuvant craniospinal irradiation (CSI). Patients were divided into those who received adjuvant CSI and chemotherapy (CRT) or CSI alone (RT). Predictors of CRT compared with RT were evaluated with univariable and multivariable logistic regression. Survival analysis was limited to patients receiving CSI doses between 23 and 36 Gy. Overall survival (OS) was evaluated using the Kaplan-Meier estimator, log-rank test, multivariable Cox proportional hazards modeling, and propensity score matching. Of the 751 patients included, 520 (69.2%) received CRT, and 231 (30.8%) received RT. With median follow-up of 5.0 years, estimated 5-year OS was superior in patients receiving CRT versus RT (86.1% vs 71.6%, P < .0001). On multivariable analysis, after controlling for risk factors, CRT was associated with superior OS compared with RT (HR: 0.53; 95%CI: 0.32-0.88, P = .01). On planned subgroup analyses, the 5 year OS of patients receiving CRT versus RT was improved for M0 patients (P < .0001), for patients receiving 36 Gy CSI (P = .0007), and for M0 patients receiving 36 Gy CSI (P = .0008). This national database analysis demonstrates that combined postoperative chemotherapy and radiotherapy are associated with superior survival for adult MB compared with radiotherapy alone, even for M0 patients who receive high-dose CSI. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Control of Cell Survival in Adult Mammalian Neurogenesis.

PubMed

Kuhn, H Georg

2015-10-28

The fact that continuous proliferation of stem cells and progenitors, as well as the production of new neurons, occurs in the adult mammalian central nervous system (CNS) raises several basic questions concerning the number of neurons required in a particular system. Can we observe continued growth of brain regions that sustain neurogenesis? Or does an elimination mechanism exist to maintain a constant number of cells? If so, are old neurons replaced, or are the new neurons competing for limited network access among each other? What signals support their survival and integration and what factors are responsible for their elimination? This review will address these and other questions regarding regulatory mechanisms that control cell-death and cell-survival mechanisms during neurogenesis in the intact adult mammalian brain. Copyright © 2015 Cold Spring Harbor Laboratory Press; all rights reserved.

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…

The probability of seizures during EEG monitoring in critically ill adults.

PubMed

Westover, M Brandon; Shafi, Mouhsin M; Bianchi, Matt T; Moura, Lidia M V R; O'Rourke, Deirdre; Rosenthal, Eric S; Chu, Catherine J; Donovan, Samantha; Hoch, Daniel B; Kilbride, Ronan D; Cole, Andrew J; Cash, Sydney S

2015-03-01

To characterize the risk for seizures over time in relation to EEG findings in hospitalized adults undergoing continuous EEG monitoring (cEEG). Retrospective analysis of cEEG data and medical records from 625 consecutive adult inpatients monitored at a tertiary medical center. Using survival analysis methods, we estimated the time-dependent probability that a seizure will occur within the next 72-h, if no seizure has occurred yet, as a function of EEG abnormalities detected so far. Seizures occurred in 27% (168/625). The first seizure occurred early (<30min of monitoring) in 58% (98/168). In 527 patients without early seizures, 159 (30%) had early epileptiform abnormalities, versus 368 (70%) without. Seizures were eventually detected in 25% of patients with early epileptiform discharges, versus 8% without early discharges. The 72-h risk of seizures declined below 5% if no epileptiform abnormalities were present in the first two hours, whereas 16h of monitoring were required when epileptiform discharges were present. 20% (74/388) of patients without early epileptiform abnormalities later developed them; 23% (17/74) of these ultimately had seizures. Only 4% (12/294) experienced a seizure without preceding epileptiform abnormalities. Seizure risk in acute neurological illness decays rapidly, at a rate dependent on abnormalities detected early during monitoring. This study demonstrates that substantial risk stratification is possible based on early EEG abnormalities. These findings have implications for patient-specific determination of the required duration of cEEG monitoring in hospitalized patients. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

The probability of seizures during EEG monitoring in critically ill adults

PubMed Central

Westover, M. Brandon; Shafi, Mouhsin M.; Bianchi, Matt T.; Moura, Lidia M.V.R.; O’Rourke, Deirdre; Rosenthal, Eric S.; Chu, Catherine J.; Donovan, Samantha; Hoch, Daniel B.; Kilbride, Ronan D.; Cole, Andrew J.; Cash, Sydney S.

2014-01-01

Objective To characterize the risk for seizures over time in relation to EEG findings in hospitalized adults undergoing continuous EEG monitoring (cEEG). Methods Retrospective analysis of cEEG data and medical records from 625 consecutive adult inpatients monitored at a tertiary medical center. Using survival analysis methods, we estimated the time-dependent probability that a seizure will occur within the next 72-h, if no seizure has occurred yet, as a function of EEG abnormalities detected so far. Results Seizures occurred in 27% (168/625). The first seizure occurred early (<30 min of monitoring) in 58% (98/168). In 527 patients without early seizures, 159 (30%) had early epileptiform abnormalities, versus 368 (70%) without. Seizures were eventually detected in 25% of patients with early epileptiform discharges, versus 8% without early discharges. The 72-h risk of seizures declined below 5% if no epileptiform abnormalities were present in the first two hours, whereas 16 h of monitoring were required when epileptiform discharges were present. 20% (74/388) of patients without early epileptiform abnormalities later developed them; 23% (17/74) of these ultimately had seizures. Only 4% (12/294) experienced a seizure without preceding epileptiform abnormalities. Conclusions Seizure risk in acute neurological illness decays rapidly, at a rate dependent on abnormalities detected early during monitoring. This study demonstrates that substantial risk stratification is possible based on early EEG abnormalities. Significance These findings have implications for patient-specific determination of the required duration of cEEG monitoring in hospitalized patients. PMID:25082090

Reduced survival in adult cystic fibrosis despite attenuated lung function decline.

PubMed

Keating, Claire; Poor, Armeen D; Liu, Xinhua; Chiuzan, Codruta; Backenroth, Daniel; Zhang, Yuan; DiMango, Emily

2017-01-01

There is limited data on disease progression and survival in adult diagnosis cystic fibrosis (CF). This study evaluates change of lung function over time and rates of death/lung transplant in adult diagnosis CF. The CF Foundation Patient Registry was reviewed for patients diagnosed 1993-2003. Rate of FEV1 decline was calculated up to 2010 for age groups 6-11, 12-17, and 18 and above. Kaplan Meier method was used for 10 and 15year survival rate calculations for patients diagnosed as adults. Cox Proportional hazards models using predictors affecting disease progression and survival without transplant were run. Between 1993 and 2003, 11,884 patients were diagnosed with CF, of which 2848 were ages 6 and older. Annual rate of change of FEV1% predicted over 5years differed by diagnosis age group: -1.42% per year for ages 6-11, -2.04% for ages 12-17 and -1.13% for ages 18-65 (p<0.0001). Pseudomonas aeruginosa infection was associated with faster rates of lung function decline in all age groups. Survival without transplant for CF patients diagnosed at ≥18years were 76% and 65% by 10 and 15years, respectively. Of adults with FEV1 of >70% predicted at diagnosis, 95% were alive without transplant at 10years, whereas of those with FEV1<40% predicted at diagnosis, 31% were alive without transplant at 10years. Lung function declines at a slower rate in adult diagnosis CF. However, particularly in those with low lung function at diagnosis, rates of death or transplant in adult diagnosis CF after 10 and 15years is not negligible. Copyright © 2016 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

Features and prevalence of patients with probable adult attention deficit hyperactivity disorder who request treatment for cocaine use disorders.

PubMed

Pérez de Los Cobos, José; Siñol, Núria; Puerta, Carmen; Cantillano, Vanessa; López Zurita, Cristina; Trujols, Joan

2011-01-30

To characterize those patients with probable adult attention deficit hyperactivity disorder (ADHD) who ask for treatment of cocaine use disorders; to estimate the prevalence of probable adult ADHD among these patients. This is a cross-sectional and multi-center study performed at outpatient resources of 12 addiction treatment centers in Spain. Participants were treatment-seeking primary cocaine abusers recruited consecutively at one center and through convenience sampling at the other centers. Assessments included semi-structured clinical interview focused on Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) ADHD criteria adapted to adulthood, and the Wender-Utah Rating Scale (WURS) for screening childhood history of ADHD according to patients. Probable adult ADHD was diagnosed when patients met DSM-IV criteria of ADHD in adulthood and scored WURS>32. All participants were diagnosed with current cocaine dependence (n=190) or abuse (n=15). Patients with probable adult ADHD, compared with patients having no lifetime ADHD, were more frequently male, reported higher impulsivity, and began to use nicotine, alcohol, cannabis, or cocaine earlier. Before starting the current treatment, patients with probable adult ADHD also showed higher cocaine craving for the previous day, less frequent cocaine abstinence throughout the previous week, and higher use of cocaine and tobacco during the previous month. Impulsivity and male gender were the only independent risk factors of probable adult ADHD in a logistic regression analysis. The prevalence of probable adult ADHD was 20.5% in the sub-sample of patients consecutively recruited (n=78). A diagnosis of probable adult ADHD strongly distinguishes among treatment-seeking cocaine primary abusers regarding past and current key aspects of their addictive disorder; one-fifth of these patients present with probable adult ADHD. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

Auditory Processing of Older Adults with Probable Mild Cognitive Impairment

ERIC Educational Resources Information Center

Edwards, Jerri D.; Lister, Jennifer J.; Elias, Maya N.; Tetlow, Amber M.; Sardina, Angela L.; Sadeq, Nasreen A.; Brandino, Amanda D.; Bush, Aryn L. Harrison

2017-01-01

Purpose: Studies suggest that deficits in auditory processing predict cognitive decline and dementia, but those studies included limited measures of auditory processing. The purpose of this study was to compare older adults with and without probable mild cognitive impairment (MCI) across two domains of auditory processing (auditory performance in…

Incidence and survival of hematological cancers among adults ages ≥75 years.

PubMed

Krok-Schoen, Jessica L; Fisher, James L; Stephens, Julie A; Mims, Alice; Ayyappan, Sabarish; Woyach, Jennifer A; Rosko, Ashley E

2018-04-13

Evaluating population-based data of hematologic malignancies (HMs) in older adults provides prognostic information for this growing demographic. Incidence rates and one- and five-year relative survival rates were examined for specific HMs among adults ages ≥75 years using data from the Surveillance, Epidemiology and End Results (SEER) Program. Hematologic malignancy cases (Hodgkin lymphoma (HL), non-Hodgkin lymphoma (NHL), multiple myeloma (MM), acute lymphocytic leukemia (ALL), chronic lymphocytic leukemia (CLL), acute myeloid leukemia (AML), and chronic myeloid leukemia (CML)) were reported to one of 18 SEER registries. Recent average annual (2010-2014) incidence rates and incidence trends from 1973 to 2014 were examined for cases ages ≥75 years. One- and five-year relative cancer survival rates were examined for adults ages ≥75 years diagnosed 2007-2013, with follow-up into 2014. From 1973 to 2014, incidence rates increased for NHL, MM, and AML, decreased for HL, and remained relatively stable for ALL, CLL, and CML among adults ages ≥75 years. The highest one- and five-year relative survival rates were observed among adults with CLL ages 75-84 years (1 year: 91.8% (95% CI = 91.8-90.8)) and 5 years: 76.5% (95% CI = 74.2-78.6)). The lowest one- and five-year survival rates were observed among adults with AML ages 75-84 (1 year: 18.2% (95% CI = 74.2-78.6) and 5 years: 2.7% (95% CI = 2.0-3.6)). Survival for older adults ages ≥75 years with HMs is poor, particularly for acute leukemia. Understanding the heterogeneity in HM outcomes among older patients may help clinicians better address the hematological cancer burden and mortality in the aging population. © 2018 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

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

2016-01-01

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.

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

Second Primary Malignant Neoplasms and Survival in Adolescent and Young Adult Cancer Survivors.

PubMed

Keegan, Theresa H M; Bleyer, Archie; Rosenberg, Aaron S; Li, Qian; Goldfarb, Melanie

2017-11-01

Although the increased incidence of second primary malignant neoplasms (SPMs) is a well-known late effect after cancer, few studies have compared survival after an SPM to survival of the same cancer occurring as first primary malignant neoplasm (PM) by age. To assess the survival impact of SPMs in adolescents and young adults (AYAs) (15-39 years) compared with that of pediatric (<15 years) and older adult (≥40 years) patients with the same SPMs. This was a population-based, retrospective cohort study of patients with cancer in 13 Surveillance, Epidemiology and End Results regions in the United States diagnosed from 1992 to 2008 and followed through 2013. Data analysis was performed between June 2016 and January 2017. Five-year relative survival was calculated overall and for each cancer occurring as a PM or SPM by age at diagnosis. The impact of SPM status on cancer-specific death was examined using multivariable Cox proportional hazards regression. A total of 15 954 pediatric, 125 750 AYAs, and 878 370 older adult patients diagnosed as having 14 cancers occurring as a PM or SPM were included. Overall, 5-year survival after an SPM was 33.1% lower for children, 20.2% lower for AYAs, and 8.3% lower for older adults compared with a PM at the same age. For the most common SPMs in AYAs, the absolute difference in 5-year survival was 42% lower for secondary non-Hodgkin lymphoma, 19% for secondary breast carcinoma, 15% for secondary thyroid carcinoma, and 13% for secondary soft-tissue sarcoma. Survival by SPM status was significantly worse in younger vs older patients for thyroid, Hodgkin lymphoma, non-Hodgkin lymphoma, acute myeloid leukemia, soft-tissue sarcoma, and central nervous system cancer. Adolescents and young adults with secondary Hodgkin lymphoma (hazard ratio [95% CI], 3.5 [1.7-7.1]); soft-tissue sarcoma (2.8 [2.1-3.9]); breast carcinoma (2.1 [1.8-2.4]); acute myeloid leukemia (1.9 [1.5-2.4]); and central nervous system cancer (1.8 [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.

Quantitative Differences in a Single Maternal Factor Determine Survival Probabilities among Drosophila Germ Cells.

PubMed

Slaidina, Maija; Lehmann, Ruth

2017-01-23

Germ cell death occurs in many species [1-3] and has been proposed as a mechanism by which the fittest, strongest, or least damaged germ cells are selected for transmission to the next generation. However, little is known about how the choice is made between germ cell survival and death. Here, we focus on the mechanisms that regulate germ cell survival during embryonic development in Drosophila. We find that the decision to die is a germ cell-intrinsic process linked to quantitative differences in germ plasm inheritance, such that higher germ plasm inheritance correlates with higher primordial germ cell (PGC) survival probability. We demonstrate that the maternal factor lipid phosphate phosphatase Wunen-2 (Wun2) regulates PGC survival in a dose-dependent manner. Since wun2 mRNA levels correlate with the levels of other maternal determinants at the single-cell level, we propose that Wun2 is used as a readout of the overall germ plasm quantity, such that only PGCs with the highest germ plasm quantity survive. Furthermore, we demonstrate that Wun2 and p53, another regulator of PGC survival, have opposite yet independent effects on PGC survival. Since p53 regulates cell death upon DNA damage and various cellular stresses, we hypothesize that together they ensure selection of the PGCs with highest germ plasm quantity and least cellular damage. Copyright © 2017 Elsevier Ltd. All rights reserved.

Assessing the effect of a partly unobserved, exogenous, binary time-dependent covariate on survival probabilities using generalised pseudo-values.

PubMed

Pötschger, Ulrike; Heinzl, Harald; Valsecchi, Maria Grazia; Mittlböck, Martina

2018-01-19

Investigating the impact of a time-dependent intervention on the probability of long-term survival is statistically challenging. A typical example is stem-cell transplantation performed after successful donor identification from registered donors. Here, a suggested simple analysis based on the exogenous donor availability status according to registered donors would allow the estimation and comparison of survival probabilities. As donor search is usually ceased after a patient's event, donor availability status is incompletely observed, so that this simple comparison is not possible and the waiting time to donor identification needs to be addressed in the analysis to avoid bias. It is methodologically unclear, how to directly address cumulative long-term treatment effects without relying on proportional hazards while avoiding waiting time bias. The pseudo-value regression technique is able to handle the first two issues; a novel generalisation of this technique also avoids waiting time bias. Inverse-probability-of-censoring weighting is used to account for the partly unobserved exogenous covariate donor availability. Simulation studies demonstrate unbiasedness and satisfying coverage probabilities of the new method. A real data example demonstrates that study results based on generalised pseudo-values have a clear medical interpretation which supports the clinical decision making process. The proposed generalisation of the pseudo-value regression technique enables to compare survival probabilities between two independent groups where group membership becomes known over time and remains partly unknown. Hence, cumulative long-term treatment effects are directly addressed without relying on proportional hazards while avoiding waiting time bias.

Survival probability of diffusion with trapping in cellular neurobiology

NASA Astrophysics Data System (ADS)

Holcman, David; Marchewka, Avi; Schuss, Zeev

2005-09-01

The problem of diffusion with absorption and trapping sites arises in the theory of molecular signaling inside and on the membranes of biological cells. In particular, this problem arises in the case of spine-dendrite communication, where the number of calcium ions, modeled as random particles, is regulated across the spine microstructure by pumps, which play the role of killing sites, while the end of the dendritic shaft is an absorbing boundary. We develop a general mathematical framework for diffusion in the presence of absorption and killing sites and apply it to the computation of the time-dependent survival probability of ions. We also compute the ratio of the number of absorbed particles at a specific location to the number of killed particles. We show that the ratio depends on the distribution of killing sites. The biological consequence is that the position of the pumps regulates the fraction of calcium ions that reach the dendrite.

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.

Does Breast Cancer Drive the Building of Survival Probability Models among States? An Assessment of Goodness of Fit for Patient Data from SEER Registries

PubMed

Khan, Hafiz; Saxena, Anshul; Perisetti, Abhilash; Rafiq, Aamrin; Gabbidon, Kemesha; Mende, Sarah; Lyuksyutova, Maria; Quesada, Kandi; Blakely, Summre; Torres, Tiffany; Afesse, Mahlet

2016-12-01

Background: Breast cancer is a worldwide public health concern and is the most prevalent type of cancer in women in the United States. This study concerned the best fit of statistical probability models on the basis of survival times for nine state cancer registries: California, Connecticut, Georgia, Hawaii, Iowa, Michigan, New Mexico, Utah, and Washington. Materials and Methods: A probability random sampling method was applied to select and extract records of 2,000 breast cancer patients from the Surveillance Epidemiology and End Results (SEER) database for each of the nine state cancer registries used in this study. EasyFit software was utilized to identify the best probability models by using goodness of fit tests, and to estimate parameters for various statistical probability distributions that fit survival data. Results: Statistical analysis for the summary of statistics is reported for each of the states for the years 1973 to 2012. Kolmogorov-Smirnov, Anderson-Darling, and Chi-squared goodness of fit test values were used for survival data, the highest values of goodness of fit statistics being considered indicative of the best fit survival model for each state. Conclusions: It was found that California, Connecticut, Georgia, Iowa, New Mexico, and Washington followed the Burr probability distribution, while the Dagum probability distribution gave the best fit for Michigan and Utah, and Hawaii followed the Gamma probability distribution. These findings highlight differences between states through selected sociodemographic variables and also demonstrate probability modeling differences in breast cancer survival times. The results of this study can be used to guide healthcare providers and researchers for further investigations into social and environmental factors in order to reduce the occurrence of and mortality due to breast cancer. Creative Commons Attribution License

Shorter survival in adolescent and young adult patients, compared to adult patients, with stage IV colorectal cancer in Japan.

PubMed

Shida, Dai; Ahiko, Yuka; Tanabe, Taro; Yoshida, Takefumi; Tsukamoto, Shunsuke; Ochiai, Hiroki; Takashima, Atsuo; Boku, Narikazu; Kanemitsu, Yukihide

2018-03-27

The incidence of colorectal cancer in adolescent and young adult patients is increasing. However, survival and clinical features of young patients, especially those with stage IV disease, relative to adult patients remain unclear. This retrospective single-institution cohort study was conducted at a tertiary care cancer center. Subjects were 861 consecutive patients who were diagnosed with stage IV colorectal cancer at the age of 15 to 74 years and who were referred to the division of surgery or gastrointestinal oncology at the National Cancer Center Hospital from 1999 to 2013. Overall survival (OS) was investigated and clinicopathological variables were analyzed for prognostic significance. Of these, 66 (8%) were adolescent and young adult patients and 795 (92%) were adult patients. Median survival time was 13.6 months in adolescent and young adult patients and 22.4 months in adult patients, and 5-year OS rates were 17.3% and 20.3%, respectively, indicating significant worse prognosis of adolescent and young adult patients (p = 0.042). However, age itself was not an independent factor associated with prognosis by multivariate analysis. When compared with adult patients, adolescent and young adult patients consisted of higher proportion of the patients who did not undergo resection of primary tumor, which was an independent factor associated with poor prognosis in multivariate analysis. In patients who did not undergo resection (n = 349), OS of adolescent and young adult patients were significantly worse (p = 0.033). Prognoses were worse in adolescent and young adult patients with stage IV colorectal cancer compared to adult patients in Japan, due to a higher proportion of patients who did not undergo resection with more advanced and severe disease, but not due to age itself.

Global divergence in critical income for adult and childhood survival: analyses of mortality using Michaelis–Menten

PubMed Central

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

2012-01-01

Life expectancy has risen sharply in the last 50 years. We applied the classic Michaelis–Menten enzyme kinetics to demonstrate a novel mathematical relationship of income to childhood (aged 0–5 years) and adult (aged 15–60 years) survival. We treat income as a substrate that is catalyzed to increase survival (from technologies that income buys) for 180 countries from 1970 and 2007. Michaelis–Menten kinetics permit estimates of maximal survival and, uniquely, the critical income needed to achieve half of the period-specific maximum. Maximum child and adult survival rose by about 1% per year. Critical incomes fell by half for children, but doubled for men. HIV infection and smoking account for some, but not all, of the rising critical incomes for adult survival. Altering the future cost curve for adult survival will require more widespread use of current interventions, most notably tobacco control, but also research to identify practicable low-cost drugs, diagnostics, and strategies. DOI: http://dx.doi.org/10.7554/eLife.00051.001 PMID:23240081

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

[Morphological signs of survival cultured adult rat cardiomyocytes].

PubMed

Chang, Hui; Zhang, Lin; Yu, Zhi-Bin

2011-02-01

To clarify the key morphological signs for the survival of adult rat cardiomyocytes in primary culture. The adult rat hearts were retrogradely superfused by Langendorff apparatus. Cardiomyocytes were digested by collagenase I and cultured in three groups: (1) Serum free medium + BA (Bongkrekic acid, apoptotic inhibitor), (2) 5% serum medium, and (3) 5% serum medium + BA. The morphological alterations were observed and the percentage of rod-shaped cardiomyocytes, the apoptotic rate of cells, the rate of pseudopodium formation and the nuclear distances of cardiomyocytes were detected during culture. (1) The percentage of rod-shaped cardiomyocytes decreased gradually in the first 3 days of cell culture. The percentage of rod-shaped cardiomyocytes cultured without fetal bovine serum (FBS) decreased more rapidly than those cultured with FBS. No differences were noticed between with and without the addition of apoptotic inhibitor BA. The apoptotic rate of cardiomyocytes increased in the first 3 days of cell culture, and the apoptotic rate of cells cultured without FBS increased more than that cultured with FBS. Also BA had no effect on apoptotic rate. (2) Cardiomyocytes cultured with FBS spread from the intercalated disk and extended pseudopodium on the second or third day of cell culture. Cardiomyocytes with thin membranous pseudopodium developed would survive and spread laterally at the 6th day of culture. Cells with the elongated morphology gradually spread extensively and took on a spheroidal shape. Myofibrils gradually lost their parallel. Cells cultured without FBS had no pseudopodium formation. The intercalated disk of cells gradually changed blunt. There was no effect on the rate of pseudopodium formation when added with apoptotic inhibitor BA. (3) Cytoskeletal remodeling occurred in survived cardiomyocytes. After 6 days of culture, cardiomyocytes exhibited characteristic of redifferentiation. (4) The distance between nuclei decreased in a single cardiomyocyte

Seasonal and annual survival of adult Pacific brant

USGS Publications Warehouse

Ward, David H.; Rexstad, Eric A.; Sedinger, James S.; Lindberg, Mark S.; Dawe, Neil K.

1997-01-01

Declining mid-winter counts of Pacific brant (Branta bernicla nigricans) and reduced numbers of nesting birds on their main breeding grounds prompted us to assess factors that may be limiting recovery of this population. We estimated seasonal and annual survival rates of adult brant in 1986-93 from resightings of leg-banded birds. Brant were banded at a major colony on the Yukon-Kuskokwim Delta, Alaska (Y-K Delta) in 1986-92, and resighted there in 1987-93 as well as at major fall and spring migration and wintering areas in 1990-93. Seasonal survival was the same for males and females. Mean monthly survival rate was lowest (P ≤ 0.05) in late spring migration (15 Apr-1 Jun), the period of greatest subsistence harvest on the breeding grounds, and highest in winter (1 Jan-1 Mar), the period of greatest sport harvest. Annual survival rate did not vary among years (F = 0.51; 5, 718 df; P = 0.91) and averaged 0.840 (SE = 0.031) from 1986 to 1993. Subsistence harvest has contributed to low population levels of Pacific brant.

Survival of adult murres and kittiwakes in relation to forage fish abundance

USGS Publications Warehouse

Piatt, John F.

2000-01-01

Some seabird populations damaged by the Exxon Valdez oil spill continue to decline or are not recovering. In order to understand the ultimate cause of seabird population fluctuations, we must measure productivity, recruitment, and adult survival. Recent APEX studies focused on measuring productivity only. Recruitment measurement demands an unrealistic study duration. We propose to augment current studies in lower Cook Inlet that relate breeding success and foraging effort to fluctuations in forage fish density by using banding and resighting to quantify the survival of adult common murres and black-legged kittiwakes.

Factors affecting breeding season survival of red-headed woodpeckers in South Carolina

Treesearch

John C. Kilgo; Mark Vukovich

2012-01-01

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¨C2007, we estimated survival probabilities of 80 radio-tagged red-headed woodpeckers during the breeding season in...

Probability of survival of implant-supported metal ceramic and CAD/CAM resin nanoceramic crowns.

PubMed

Bonfante, Estevam A; Suzuki, Marcelo; Lorenzoni, Fábio C; Sena, Lídia A; Hirata, Ronaldo; Bonfante, Gerson; Coelho, Paulo G

2015-08-01

To evaluate the probability of survival and failure modes of implant-supported resin nanoceramic relative to metal-ceramic crowns. Resin nanoceramic molar crowns (LU) (Lava Ultimate, 3M ESPE, USA) were milled and metal-ceramic (MC) (Co-Cr alloy, Wirobond C+, Bego, USA) with identical anatomy were fabricated (n=21). The metal coping and a burnout-resin veneer were created by CAD/CAM, using an abutment (Stealth-abutment, Bicon LLC, USA) and a milled crown from the LU group as models for porcelain hot-pressing (GC-Initial IQ-Press, GC, USA). Crowns were cemented, the implants (n=42, Bicon) embedded in acrylic-resin for mechanical testing, and subjected to single-load to fracture (SLF, n=3 each) for determination of step-stress profiles for accelerated-life testing in water (n=18 each). Weibull curves (50,000 cycles at 200N, 90% CI) were plotted. Weibull modulus (m) and characteristic strength (η) were calculated and a contour plot used (m versus η) for determining differences between groups. Fractography was performed in SEM and polarized-light microscopy. SLF mean values were 1871N (±54.03) for MC and 1748N (±50.71) for LU. Beta values were 0.11 for MC and 0.49 for LU. Weibull modulus was 9.56 and η=1038.8N for LU, and m=4.57 and η=945.42N for MC (p>0.10). Probability of survival (50,000 and 100,000 cycles at 200 and 300N) was 100% for LU and 99% for MC. Failures were cohesive within LU. In MC crowns, porcelain veneer fractures frequently extended to the supporting metal coping. Probability of survival was not different between crown materials, but failure modes differed. In load bearing regions, similar reliability should be expected for metal ceramics, known as the gold standard, and resin nanoceramic crowns over implants. Failure modes involving porcelain veneer fracture and delamination in MC crowns are less likely to be successfully repaired compared to cohesive failures in resin nanoceramic material. Copyright © 2015 Academy of Dental Materials

Adult survival and productivity of Northern Fulmars in Alaska

USGS Publications Warehouse

Hatch, Scott A.

1987-01-01

The population dynamics of Northern Fulmars (Fulmarus glacialis) were studied at the Semidi Islands in the western Gulf of Alaska. Fulmars occurred in a broad range of color phases, and annual survival was estimated from the return of birds in the rarer plumage classes. A raw estimate of mean annual survival over a 5-year period was 0.963, but a removal experiment indicated the raw value was probably biased downward. The estimate of annual survival adjusted accordingly was 0.969. Mortality during the breeding season was less than 10% of the annual total, and postbreeding mortality of failed breeders was three to four times higher than that of successful breeders. Breeding success averaged 41% over 9 years. About 5% of experienced birds failed to breed each year due to physical destruction of their breeding sites, mate-loss, or other causes. An estimated 30% of the birds near the colony in one year were of prebreeding age. A comparison of population parameters in Pacific and Atlantic fulmars indicates that higher survival in the prebreeding years is the likely basis for population growth in the northeastern Atlantic. The correlation of breeding success and survival suggests both parameters may decline with age.

Effects of Pesticides on the Survival of Rove Beetle (Coleoptera: Staphylinidae) and Insidious Flower Bug (Hemiptera: Anthocoridae) Adults.

PubMed

Cloyd, Raymond A; Herrick, Nathan J

2018-02-09

This study determined the direct, indirect, or both effects of pesticides on the rove beetle, Dalotia coriaria (Kraatz) (Coleoptera: Staphylinidae), and the insidious flower bug, Orius insidiosus (Say) (Hemiptera: Anthocoridae). The pesticides evaluated were Capsicum oleoresin extract, garlic oil, and soybean oil; cyantraniliprole; flupyradifurone; GS-omega/kappa-Hxtx-Hv1; Isaria fumosorosea; tolfenpyrad; pyrethrins; and spinosad. One experiment was conducted in a greenhouse with rove beetle adults exposed to growing medium applications of cyantraniliprole. The number of live and dead rove beetle adults was determined after 10 d. Four additional experiments were conducted under laboratory conditions. Rove beetle or insidious flower bug adults were individually placed into Petri dishes with filter paper treated with the pesticides. After 24, 48, 72, and 96 h, the number of live and dead adults of both natural enemies was recorded. GS-omega/kappa-Hxtx-Hv1 (VST-006340LC); tolfenpyrad; Capsicum oleoresin extract, garlic oil, and soybean oil (Captiva); and Isaria fumosorosea were not directly harmful to O. insidiosus (80-100% adult survival). Likewise, the pesticides such as tolfenpyrad, Captiva, and I. fumosoroea were not directly harmful to D. coriaria (80-100% adult survival). D. coriaria was more sensitive to VST-006340LC (40% survival) than O. insidiosus (100% survival), whereas O. insidiosus was more sensitive to flupyradifurone (0% survival) than D. coriaria (80% and 40% survival for both rates tested, respectively). The pesticides pyrethrins, spinosad, flupyradifurone, and combinations of tolfenpyrad and Captiva were directly harmful (<50% adult survival) to both natural enemies. However, none of the pesticides tested affected the ability of O. insidiosus adults to feed on western flower thrips adults. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please email

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…

Survival after stem-cell transplant in pediatric and young-adult patients with relapsed and refractory B-cell acute lymphoblastic leukemia.

PubMed

Crotta, Alessandro; Zhang, Jie; Keir, Christopher

2018-03-01

Allogeneic stem-cell transplant (allo-SCT) is the standard of care for pediatric patients with acute lymphoblastic leukemia (ALL) who relapse after frontline chemotherapy; however, for patients who relapse after allo-SCT, outcomes are very poor. Few studies have examined overall survival in this patient population, particularly in patients who received a second allo-SCT. This was a retrospective analysis using data from the Center for International Blood and Marrow Transplant Research (CIBMTR) registry. The study population included patients aged 3 to 21 years who were diagnosed with B-ALL and underwent their first allo-SCT between 2009 and 2013. The primary endpoint was the time from the date of posttransplant relapse to the date of death due to any reason. Outcomes in 1349 pediatric and young-adult patients were included in this analysis. The Kaplan-Meier estimated probability of survival at 3 years after first allo-SCT was 63.1% (95% CI, 60.2%-65.8%). Overall, 29.2% of patients relapsed after first allo-SCT and had a median survival of 7.4 months (95% CI, 6.0-9.6 months). Twenty-five patients in the analysis developed secondary malignancies, most of which were lymphoproliferative disorders. Survival rates are low in pediatric and young-adult patients who relapse after first and second allo-SCT, and new therapies are needed to improve outcomes in this population. This data can be used as a historical comparison for single-arm trials of novel therapies for this patient population, including chimeric antigen receptor T-cell therapy.

Survival of adult female northern pintails in Sacramento Valley, California

USGS Publications Warehouse

Miller, Michael R.; Fleskes, Joseph P.; Orthmeyer, Dennis L.; Newton, Wesley E.; Gilmer, David S.

1995-01-01

North American populations of northern pintails (Anas acuta) declined between 1979 and the early 1990s. To determine if low survival during winter contributed to declines, we estimated winter (last week of Aug-Feb 1987-90) survival for 190 adult (after hatching yr [AHY]) female radio-tagged pintails in late summer in Sacramento Valley (SACV), California. Survival rates did not vary by winter (P = 0.808), among preseason, hunting season, or postseason intervals (P = 0.579), or by body mass at time of capture (P = 0.127). Premolt (wing) pintails (n = 10) tended to survive at a lower rate (0.622, SE = 0.178) than pintails that had already replaced flight feathers (0.887, SE = 0.030) (P = 0.091). The pooled survival (all years) estimate for the 180-day winter was 0.874 (SE = 0.031). Hunting mortality rate (0.041-0.087) and nonhunting mortality rate (0.013-0.076) did not differ among years (P = 0.332) or within years (all P > 0.149). Legal hunting (n = 7), predation (n = 4), cholera (n = 2), illegal shooting (n = 2), botulism (n = 1), and unknown cause (n = 1) accounted for all mortality. Nonwintering survival (annu. survival/winter survival = 0.748) was lower than winter survival; thus, if gains in annual survival are desired for this population, managers should first examine the breeding-migration period for opportunities to achieve increases.

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.

Survival of adult Steller sea lions in Alaska: senescence, annual variation and covariation with male reproductive success.

PubMed

Hastings, Kelly K; Jemison, Lauri A; Pendleton, Grey W

2018-01-01

Population dynamics of long-lived vertebrates depend critically on adult survival, yet factors affecting survival and covariation between survival and other vital rates in adults remain poorly examined for many taxonomic groups of long-lived mammals (e.g. actuarial senescence has been examined for only 9 of 34 extant pinniped species using longitudinal data). We used mark-recapture models and data from 2795 Steller sea lion ( Eumetopias jubatus ) pups individually marked at four of five rookeries in southeastern Alaska (SEAK) and resighted for 21 years to examine senescence, annual variability and covariation among life-history traits in this long-lived, sexually dimorphic pinniped. Sexes differed in age of onset (approx. 16-17 and approx. 8-9 years for females and males, respectively), but not rate (-0.047 and -0.046/year of age for females and males) of senescence. Survival of adult males from northern SEAK had greatest annual variability (approx. ±0.30 among years), whereas survival of adult females ranged approximately ±0.10 annually. Positive covariation between male survival and reproductive success was observed. Survival of territorial males was 0.20 higher than that of non-territorial males, resulting in the majority of males alive at oldest ages being territorial.

Survival of adult Steller sea lions in Alaska: senescence, annual variation and covariation with male reproductive success

PubMed Central

Jemison, Lauri A.; Pendleton, Grey W.

2018-01-01

Population dynamics of long-lived vertebrates depend critically on adult survival, yet factors affecting survival and covariation between survival and other vital rates in adults remain poorly examined for many taxonomic groups of long-lived mammals (e.g. actuarial senescence has been examined for only 9 of 34 extant pinniped species using longitudinal data). We used mark–recapture models and data from 2795 Steller sea lion (Eumetopias jubatus) pups individually marked at four of five rookeries in southeastern Alaska (SEAK) and resighted for 21 years to examine senescence, annual variability and covariation among life-history traits in this long-lived, sexually dimorphic pinniped. Sexes differed in age of onset (approx. 16–17 and approx. 8–9 years for females and males, respectively), but not rate (−0.047 and −0.046/year of age for females and males) of senescence. Survival of adult males from northern SEAK had greatest annual variability (approx. ±0.30 among years), whereas survival of adult females ranged approximately ±0.10 annually. Positive covariation between male survival and reproductive success was observed. Survival of territorial males was 0.20 higher than that of non-territorial males, resulting in the majority of males alive at oldest ages being territorial. PMID:29410794

Patient volume per surgeon does not predict survival in adult level I trauma centers.

PubMed

Margulies, D R; Cryer, H G; McArthur, D L; Lee, S S; Bongard, F S; Fleming, A W

2001-04-01

The 1999 American College of Surgeons resources for optimal care document added the requirement that Level I trauma centers admit over 240 patients with Injury Severity Score (ISS) > 15 per year or that trauma surgeons care for at least 35 patients per year. The purpose of this study was to test the hypothesis that high volume of patients with ISS > 15 per individual trauma surgeon is associated with improved outcome. Data were obtained from the trauma registry of the five American College of Surgeons-verified adult Level I trauma centers in our mature trauma system between January 1, 1998, and March 31, 1999. Data abstracted included age, sex, Glasgow Coma Scale (GCS) score, intensive care unit length of stay, hospital length of stay, probability of survival (Ps), mechanism of injury, number of patients per each trauma surgeon and institution, and mortality. Multiple logistic regression was performed to select independent variables for modeling of survival. From the five Level I centers there were 11,932 trauma patients in this time interval; of these, 1,754 patients (14.7%) with ISS > 15 were identified and used for analysis. Patients with ISS > 15 varied from 173 to 625 per institution; trauma surgeons varied from 8 to 25 per institution; per-surgeon patient volume varied from 0.8 to 96 per year. Logistic regression analysis revealed that the best independent predictors of survival were Ps, GCS score, age, mechanism of injury, and institutional volume (p < 0.01). Age and institutional volume correlated negatively with survival. Analysis of per-surgeon patient caseload added no additional predictive value (p = 0.44). The significant independent predictors of survival in severely injured trauma patients are Ps, GCS score, age, mechanism of injury, and institutional volume. We found no statistically meaningful contribution to the prediction of survival on the basis of per-surgeon patient volume. Since this volume criterion for surgeon enpanelment and trauma center

Does private religious activity prolong survival? A six-year follow-up study of 3,851 older adults.

PubMed

Helm, H M; Hays, J C; Flint, E P; Koenig, H G; Blazer, D G

2000-07-01

Previous studies have linked higher religious attendance and longer survival. In this study, we examine the relationship between survival and private religious activity. A probability sample of elderly community-dwelling adults in North Carolina was assembled in 1986 and followed for 6 years. Level of participation in private religious activities such as prayer, meditation, or Bible study was assessed by self-report at baseline, along with a wide variety of sociodemographic and health variables. The main outcome was time (days) to death or censoring. During a median 6.3-year follow-up period, 1,137 subjects (29.5%) died. Those reporting rarely to never participating in private religious activity had an increased relative hazard of dying over more frequent participants, but this hazard did not remain significant for the sample as a whole after adjustment for demographic and health variables. When the sample was divided into activity of daily living (ADL) impaired and unimpaired, the effect did not remain significant for the ADL impaired group after controlling for demographic variables (hazard ratio [RH] 1.11, 95% confidence interval [CI] 0.91-1.35). However, the increased hazard remained significant for the ADL unimpaired group even after controlling for demographic and health variables (RH 1.63, 95% CI 1.20-2.21), and this effect persisted despite controlling for numerous explanatory variables including health practices, social support, and other religious practices (RH 1.47, 95% CI 1.07-2.03). Older adults who participate in private religious activity before the onset of ADL impairment appear to have a survival advantage over those who do not.

Incidence and Survival After In-Hospital Cardiopulmonary Resuscitation in Nonelderly Adults: US Experience, 2007 to 2012.

PubMed

Mallikethi-Reddy, Sagar; Briasoulis, Alexandros; Akintoye, Emmanuel; Jagadeesh, Kavyashri; Brook, Robert D; Rubenfire, Melvyn; Afonso, Luis; Grines, Cindy L

2017-02-01

Survival trends after in-hospital cardiopulmonary resuscitation (ICPR) for cardiac arrest in nonelderly adults is not well known. Influence of cardiopulmonary resuscitation guidelines on nationwide survival after ICPR is yet to be well elucidated. We examined survival trends and factors associated with survival after ICPR in nonelderly adults aged 18 to 64 years, using Healthcare Utilization Project Nationwide Inpatient Sample Database from 2007 through 2012 in the United States. Furthermore, we studied the impact of 2010 American Heart Association cardiopulmonary resuscitation guidelines on survival. We identified 235 959 patients who underwent ICPR after cardiac arrest. Overall, 30.4% patients survived to hospital discharge. Survival improved from 27.4% in 2007 to 32.8% in 2012 ( P trend <0.001). Shockable arrest rhythms were noted in 23.3% of patients. Incidence of ICPR increased from 1.81 per 1000 hospitalizations in 2007 to 2.37 per 1000 hospitalizations in 2012 ( P trend <0.001). There was no statistically significant change in survival trends before and after 2010 cardiopulmonary resuscitation guidelines. Female sex and shockable rhythms were associated with higher adjusted odds of survival, whereas black race, lack of health insurance, age, and weekend admission were associated with lower adjusted odds of survival. Among nonelderly adults, survival after ICPR improved significantly from 2007 through 2012, with an overall survival rate of 30.4%. Incidence of ICPR increased significantly during the study period. There was no statistically significant change in survival before and after 2010 cardiopulmonary resuscitation guidelines. Female sex and black race were associated with higher and lower odds of survival, respectively. © 2017 American Heart Association, Inc.

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

PubMed Central

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) =1.8; 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

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.

Factors Associated With Ischemic Stroke Survival and Recovery in Older Adults.

PubMed

Winovich, Divya Thekkethala; Longstreth, William T; Arnold, Alice M; Varadhan, Ravi; Zeki Al Hazzouri, Adina; Cushman, Mary; Newman, Anne B; Odden, Michelle C

2017-07-01

Little is known about factors that predispose older adults to poor recovery after a stroke. In this study, we sought to evaluate prestroke measures of frailty and related factors as markers of vulnerability to poor outcomes after ischemic stroke. In participants aged 65 to 99 years with incident ischemic strokes from the Cardiovascular Health Study, we evaluated the association of several risk factors (frailty, frailty components, C-reactive protein, interleukin-6, and cystatin C) assessed before stroke with stroke outcomes of survival, cognitive decline (≥5 points on Modified Mini-Mental State Examination), and activities of daily living decline (increase in limitations). Among 717 participants with incident ischemic stroke with survival data, slow walking speed, low grip strength, and cystatin C were independently associated with shorter survival. Among participants <80 years of age, frailty and interleukin-6 were also associated with shorter survival. Among 509 participants with recovery data, slow walking speed, and low grip strength were associated with both cognitive and activities of daily living decline poststroke. C-reactive protein and interleukin-6 were associated with poststroke cognitive decline among men only. Frailty status was associated with activities of daily living decline among women only. Markers of physical function-walking speed and grip strength-were consistently associated with survival and recovery after ischemic stroke. Inflammation, kidney function, and frailty also seemed to be determinants of survival and recovery after an ischemic stroke. These markers of vulnerability may identify targets for differing pre and poststroke medical management and rehabilitation among older adults at risk of poor stroke outcomes. © 2017 American Heart Association, Inc.

Conspecific Leaf Litter-Mediated Effect of Conspecific Adult Neighborhood on Early-Stage Seedling Survival in A Subtropical Forest.

PubMed

Liu, Heming; Shen, Guochun; Ma, Zunping; Yang, Qingsong; Xia, Jianyang; Fang, Xiaofeng; Wang, Xihua

2016-11-25

Conspecific adults have strong negative effect on the survival of nearby early-stage seedlings and thus can promote species coexistence by providing space for the regeneration of heterospecifics. The leaf litter fall from the conspecific adults, and it could mediate this conspecific negative adult effect. However, field evidence for such effect of conspecific leaf litter remains absent. In this study, we used generalized linear mixed models to assess the effects of conspecific leaf litter on the early-stage seedling survival of four dominant species (Machilus leptophylla, Litsea elongate, Acer pubinerve and Distylium myricoides) in early-stage seedlings in a subtropical evergreen broad-leaved forest in eastern China. Our results consistently showed that the conspecific leaf litter of three species negatively affected the seedling survival. Meanwhile, the traditional conspecific adult neighborhood indices failed to detect this negative conspecific adult effect. Our study revealed that the accumulation of conspecific leaf litter around adults can largely reduce the survival rate of nearby seedlings. Ignoring it could result in underestimation of the importance of negative density dependence and negative species interactions in the natural forest communities.

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.

Conspecific Leaf Litter-Mediated Effect of Conspecific Adult Neighborhood on Early-Stage Seedling Survival in A Subtropical Forest

PubMed Central

Liu, Heming; Shen, Guochun; Ma, Zunping; Yang, Qingsong; Xia, Jianyang; Fang, Xiaofeng; Wang, Xihua

2016-01-01

Conspecific adults have strong negative effect on the survival of nearby early-stage seedlings and thus can promote species coexistence by providing space for the regeneration of heterospecifics. The leaf litter fall from the conspecific adults, and it could mediate this conspecific negative adult effect. However, field evidence for such effect of conspecific leaf litter remains absent. In this study, we used generalized linear mixed models to assess the effects of conspecific leaf litter on the early-stage seedling survival of four dominant species (Machilus leptophylla, Litsea elongate, Acer pubinerve and Distylium myricoides) in early-stage seedlings in a subtropical evergreen broad-leaved forest in eastern China. Our results consistently showed that the conspecific leaf litter of three species negatively affected the seedling survival. Meanwhile, the traditional conspecific adult neighborhood indices failed to detect this negative conspecific adult effect. Our study revealed that the accumulation of conspecific leaf litter around adults can largely reduce the survival rate of nearby seedlings. Ignoring it could result in underestimation of the importance of negative density dependence and negative species interactions in the natural forest communities. PMID:27886275

Survival probability of an edge Majorana in a one-dimensional p-wave superconducting chain under sudden quenching of parameters

NASA Astrophysics Data System (ADS)

Rajak, Atanu; Dutta, Amit

2014-04-01

We consider the temporal evolution of a zero-energy edge Majorana of a spinless p-wave superconducting chain following a sudden change of a parameter of the Hamiltonian. Starting from one of the topological phases that has an edge Majorana, the system is suddenly driven to the other topological phase or to the (topologically) trivial phases and to the quantum critical points (QCPs) separating these phases. The survival probability of the initial edge Majorana as a function of time is studied following the quench. Interestingly when the chain is quenched to the QCP, we find a nearly perfect oscillation of the survival probability, indicating that the Majorana travels back and forth between two ends, with a time period that scales with the system size. We also generalize to the situation when there is a next-nearest-neighbor hopping in a superconducting chain and there results in a pair of edge Majorana at each end of the chain in the topological phase. We show that the frequency of oscillation of the survival probability gets doubled in this case. We also perform an instantaneous quenching of the Hamiltonian (with two Majorana modes at each end of the chain) to an another Hamiltonian which has only one Majorana mode in equilibrium; the MSP shows oscillations as a function of time with a noticeable decay in the amplitude. On the other hand for a quenching which is reverse to the previous one, the MSP decays rapidly and stays close to zero with fluctuations in amplitude.

Surviving Parents' Influence on Adult Children's Depressive Symptoms Following the Death of a First Parent.

PubMed

Stokes, Jeffrey E

2016-10-01

Parents and children are linked across the life course, and they share common experiences. This article focuses on the bereavement experience of adult children's loss of a first parent during adulthood and examines the downward influence of emotional closeness with a surviving parent on adult children's depressive symptoms following loss. Analyses are based on adult children who experienced the death of a first parent (N = 227), drawn from the Longitudinal Study of Generations, a study of three-and four-generation families from Southern California. Multilevel lagged dependent variable models indicate that an emotionally close relationship with a surviving parent is related with fewer post-bereavement depressive symptoms when a mother survives a father, but not vice versa. This analysis extends the theory of linked lives and highlights the mutual influence parents and children exert, as well as the complex role of gender in shaping family relationships. © The Author(s) 2014.

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

PubMed

Hudson Kam, Carla L

2009-04-01

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.

Survival analysis using inverse probability of treatment weighted methods based on the generalized propensity score.

PubMed

Sugihara, Masahiro

2010-01-01

In survival analysis, treatment effects are commonly evaluated based on survival curves and hazard ratios as causal treatment effects. In observational studies, these estimates may be biased due to confounding factors. The inverse probability of treatment weighted (IPTW) method based on the propensity score is one of the approaches utilized to adjust for confounding factors between binary treatment groups. As a generalization of this methodology, we developed an exact formula for an IPTW log-rank test based on the generalized propensity score for survival data. This makes it possible to compare the group differences of IPTW Kaplan-Meier estimators of survival curves using an IPTW log-rank test for multi-valued treatments. As causal treatment effects, the hazard ratio can be estimated using the IPTW approach. If the treatments correspond to ordered levels of a treatment, the proposed method can be easily extended to the analysis of treatment effect patterns with contrast statistics. In this paper, the proposed method is illustrated with data from the Kyushu Lipid Intervention Study (KLIS), which investigated the primary preventive effects of pravastatin on coronary heart disease (CHD). The results of the proposed method suggested that pravastatin treatment reduces the risk of CHD and that compliance to pravastatin treatment is important for the prevention of CHD. (c) 2009 John Wiley & Sons, Ltd.

Multiple Diseases in Carrier Probability Estimation: Accounting for Surviving All Cancers Other than Breast and Ovary in BRCAPRO

PubMed Central

Katki, Hormuzd A.; Blackford, Amanda; Chen, Sining; Parmigiani, Giovanni

2008-01-01

SUMMARY Mendelian models can predict who carries an inherited deleterious mutation of known disease genes based on family history. For example, the BRCAPRO model is commonly used to identify families who carry mutations of BRCA1 and BRCA2, based on familial breast and ovarian cancers. These models incorporate the age of diagnosis of diseases in relatives and current age or age of death. We develop a rigorous foundation for handling multiple diseases with censoring. We prove that any disease unrelated to mutations can be excluded from the model, unless it is sufficiently common and dependent on a mutation-related disease time. Furthermore, if a family member has a disease with higher probability density among mutation carriers, but the model does not account for it, then the carrier probability is deflated. However, even if a family only has diseases the model accounts for, if the model excludes a mutation-related disease, then the carrier probability will be inflated. In light of these results, we extend BRCAPRO to account for surviving all non-breast/ovary cancers as a single outcome. The extension also enables BRCAPRO to extract more useful information from male relatives. Using 1500 familes from the Cancer Genetics Network, accounting for surviving other cancers improves BRCAPRO’s concordance index from 0.758 to 0.762 (p = 0.046), improves its positive predictive value from 35% to 39% (p < 10−6) without impacting its negative predictive value, and improves its overall calibration, although calibration slightly worsens for those with carrier probability < 10%. PMID:18407567

Multiple diseases in carrier probability estimation: accounting for surviving all cancers other than breast and ovary in BRCAPRO.

PubMed

Katki, Hormuzd A; Blackford, Amanda; Chen, Sining; Parmigiani, Giovanni

2008-09-30

Mendelian models can predict who carries an inherited deleterious mutation of known disease genes based on family history. For example, the BRCAPRO model is commonly used to identify families who carry mutations of BRCA1 and BRCA2, based on familial breast and ovarian cancers. These models incorporate the age of diagnosis of diseases in relatives and current age or age of death. We develop a rigorous foundation for handling multiple diseases with censoring. We prove that any disease unrelated to mutations can be excluded from the model, unless it is sufficiently common and dependent on a mutation-related disease time. Furthermore, if a family member has a disease with higher probability density among mutation carriers, but the model does not account for it, then the carrier probability is deflated. However, even if a family only has diseases the model accounts for, if the model excludes a mutation-related disease, then the carrier probability will be inflated. In light of these results, we extend BRCAPRO to account for surviving all non-breast/ovary cancers as a single outcome. The extension also enables BRCAPRO to extract more useful information from male relatives. Using 1500 families from the Cancer Genetics Network, accounting for surviving other cancers improves BRCAPRO's concordance index from 0.758 to 0.762 (p=0.046), improves its positive predictive value from 35 to 39 per cent (p<10(-6)) without impacting its negative predictive value, and improves its overall calibration, although calibration slightly worsens for those with carrier probability<10 per cent. Copyright (c) 2008 John Wiley & Sons, Ltd.

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

Adult survival, apparent lamb survival, and body condition of desert bighorn sheep in relation to habitat and precipitation on the Kofa National Wildlife Refuge, Arizona

USGS Publications Warehouse

Overstreet, Matthew; Caldwell, Colleen A.; Cain, James W.

2014-01-01

The decline of desert bighorn sheep on the Kofa National Wildlife Refuge (KNWR) beginning in 2003 stimulated efforts to determine the factors limiting survival and recruitment. We 1) determined pregnancy rates, body fat, and estimated survival rates of adults and lambs; 2) investigated the relationship between precipitation, forage conditions, previous year’s reproductive success, and adult body condition; 3) assessed the relative influence of body condition of adult females, precipitation, and forage characteristics on apparent survival of lambs; and 4) determined the prevalence of disease. To assess the influence of potential limiting factors on female desert bighorn sheep on the KNWR, we modeled percent body fat of adult females as a function of previous year’s reproductive effort, age class, and forage conditions (i.e., seasonal NDVI and seasonal precipitation). In addition, we assessed the relative influence of the body condition of adult females, precipitation, and forage conditions (NDVI) on length of time a lamb was observed at heel.Adult female survival was high in both 2009 (0.90 [SE = 0.05]) and 2010 (0.96 [SE = 0.03]). Apparent lamb survival to 6 months of age was 0.23 (SE = 0.05) during 2009-2010 and 0.21 (SE = 0.05) during 2010-2011 lambing seasons. Mean body fat for adult females was 12.03% (SE = 0.479) in 2009-2010 and 11.11% (SE= 0.486) in 2010-2011 and was not significantly different between years. Pregnancy rate was 100% in 2009 and 97.5% in 2010.Models containing the previous year’s reproductive effort, spring NDVI and previous year’s reproductive effort and spring precipitation best approximated data on percent body fat in adult females in 2009-2010. In 2010-2011, the two highest-ranking models included the previous year’s reproductive effort and winter NDVI and previous year’s reproductive effort, and winter and spring NDVI. None of the models assessing the influence of maternal body fat, precipitation, or forage conditions were

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

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

Testing for handling bias in survival estimation for black brant

USGS Publications Warehouse

Sedinger, J.S.; Lindberg, M.S.; Rexstad, E.A.; Chelgren, N.D.; Ward, D.H.

1997-01-01

We used an ultrastructure approach in program SURVIV to test for, and remove, bias in survival estimates for the year following mass banding of female black brant (Branta bernicla nigricans). We used relative banding-drive size as the independent variable to control for handling effects in our ultrastructure models, which took the form: S = S0(1 - ??D), where ?? was handling effect and D was the ratio of banding-drive size to the largest banding drive. Brant were divided into 3 classes: goslings, initial captures, and recaptures, based on their state at the time of banding, because we anticipated the potential for heterogeneity in model parameters among classes of brant. Among models examined, for which ?? was not constrained, a model with ?? constant across classes of brant and years, constant survival rates among years for initially captured brant but year-specific survival rates for goslings and recaptures, and year- and class-specific detection probabilities had the lowest Akaike Information Criterion (AIC). Handling effect, ??, was -0.47 ?? 0.13 SE, -0.14 ?? 0.057, and -0.12 ?? 0.049 for goslings, initially released adults, and recaptured adults. Gosling annual survival in the first year ranged from 0.738 ?? 0.072 for the 1986 cohort to 0.260 ?? 0.025 for the 1991 cohort. Inclusion of winter observations increased estimates of first-year survival rates by an average of 30%, suggesting that permanent emigration had an important influence on apparent survival, especially for later cohorts. We estimated annual survival for initially captured brant as 0.782 ?? 0.013, while that for recaptures varied from 0.726 ?? 0.034 to 0.900 ?? 0.062. Our analyses failed to detect a negative effect of handling on survival of brant, which is consistent with an hypothesis of substantial inherent heterogeneity in post-fledging survival rates, such that individuals most likely to die as a result of handling also have lower inherent survival probabilities.

Insomnia medication use and the probability of an accidental event in an older adult population

PubMed Central

Avidan, Alon Y; Palmer, Liisa A; Doan, Justin F; Baran, Robert W

2010-01-01

Objective: This study examined the risk of accidental events in older adults prescribed a sedating antidepressant, long-acting benzodiazepine, short-acting benzodiazepine, and nonbenzodiazepine, relative to a reference group (selective melatonin receptor agonist). Methods: This was a retrospective cohort analysis of older adults (≥65 years) with newly initiated pharmacological treatment of insomnia. Data were collected from the Thomson MarketScan® Medicare Supplemental and Coordination of Benefits databases (January 1, 2000, through June 30, 2006). Probit models were used to evaluate the probability of an accidental event. Results: Data were analyzed for 445,329 patients. Patients taking a long-acting benzodiazepine (1.21 odds ratio [OR]), short-acting benzodiazepine (1.16 OR), or nonbenzodiazepine (1.12 OR) had a significantly higher probability of experiencing an accidental event during the first month following treatment initiation compared with patients taking the reference medication (P < 0.05 for all). A significantly higher probability of experiencing an accidental event was also observed during the 3-month period following the initiation of treatment (1.62 long-acting benzodiazepine, 1.60 short-acting benzodiazepine, 1.48 nonbenzodiazepine, and 1.56 sedating antidepressant; P < 0.05). Conclusions: Older adults taking an SAD or any of the benzodiazepine receptor agonists appear to have a greater risk of an accidental event compared with a reference group taking an MR. PMID:21701634

Survival of adult neurons lacking cholesterol synthesis in vivo

PubMed Central

Fünfschilling, Ursula; Saher, Gesine; Xiao, Le; Möbius, Wiebke; Nave, Klaus-Armin

2007-01-01

Background Cholesterol, an essential component of all mammalian plasma membranes, is highly enriched in the brain. Both during development and in the adult, brain cholesterol is derived from local cholesterol synthesis and not taken up from the circulation. However, the contribution of neurons and glial cells to total brain cholesterol metabolism is unknown. Results Using conditional gene inactivation in the mouse, we disrupted the squalene synthase gene (fdft1), which is critical for cholesterol synthesis, in cerebellar granule cells and some precerebellar nuclei. Mutant mice showed no histological signs of neuronal degeneration, displayed ultrastructurally normal synapses, and exhibited normal motor coordination. This revealed that these adult neurons do not require cell-autonomous cholesterol synthesis for survival or function. Conclusion We conclude that at least some adult neurons no longer require endogenous cholesterol synthesis and can fully meet their cholesterol needs by uptake from their surrounding. Glia are a likely source of cholesterol in the central nervous system. PMID:17199885

Survival of adult neurons lacking cholesterol synthesis in vivo.

PubMed

Fünfschilling, Ursula; Saher, Gesine; Xiao, Le; Möbius, Wiebke; Nave, Klaus-Armin

2007-01-02

Cholesterol, an essential component of all mammalian plasma membranes, is highly enriched in the brain. Both during development and in the adult, brain cholesterol is derived from local cholesterol synthesis and not taken up from the circulation. However, the contribution of neurons and glial cells to total brain cholesterol metabolism is unknown. Using conditional gene inactivation in the mouse, we disrupted the squalene synthase gene (fdft1), which is critical for cholesterol synthesis, in cerebellar granule cells and some precerebellar nuclei. Mutant mice showed no histological signs of neuronal degeneration, displayed ultrastructurally normal synapses, and exhibited normal motor coordination. This revealed that these adult neurons do not require cell-autonomous cholesterol synthesis for survival or function. We conclude that at least some adult neurons no longer require endogenous cholesterol synthesis and can fully meet their cholesterol needs by uptake from their surrounding. Glia are a likely source of cholesterol in the central nervous system.

Estimating prefledging survival: Allowing for brood mixing and dependence among brood mates

USGS Publications Warehouse

Flint, Paul L.; Pollock, Kenneth H.; Thomas, Dana; Sedinger, James S.

1995-01-01

Estimates of juvenile survival from hatch to fledging provide important information on waterfowl productivity. We develop a model for estimating survival of young waterfowl from hatch to fledging. Our model enables interchange of individuals among broods and relaxes the assumption that individuals within broods have independent survival probabilities. The model requires repeated observations of individually identifiable adults and their offspring that are not individually identifiable. A modified Kaplan-Meier procedure (Pollock et al. 1989a,b) and a modified Mayfield procedure (Mayfield 1961, 1975; Johnson 1979) can be used under this general modeling framework, and survival rates and corresponding variances of the point estimators can be determined.

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

Survival modeling for the estimation of transition probabilities in model-based economic evaluations in the absence of individual patient data: a tutorial.

PubMed

Diaby, Vakaramoko; Adunlin, Georges; Montero, Alberto J

2014-02-01

Survival modeling techniques are increasingly being used as part of decision modeling for health economic evaluations. As many models are available, it is imperative for interested readers to know about the steps in selecting and using the most suitable ones. The objective of this paper is to propose a tutorial for the application of appropriate survival modeling techniques to estimate transition probabilities, for use in model-based economic evaluations, in the absence of individual patient data (IPD). An illustration of the use of the tutorial is provided based on the final progression-free survival (PFS) analysis of the BOLERO-2 trial in metastatic breast cancer (mBC). An algorithm was adopted from Guyot and colleagues, and was then run in the statistical package R to reconstruct IPD, based on the final PFS analysis of the BOLERO-2 trial. It should be emphasized that the reconstructed IPD represent an approximation of the original data. Afterwards, we fitted parametric models to the reconstructed IPD in the statistical package Stata. Both statistical and graphical tests were conducted to verify the relative and absolute validity of the findings. Finally, the equations for transition probabilities were derived using the general equation for transition probabilities used in model-based economic evaluations, and the parameters were estimated from fitted distributions. The results of the application of the tutorial suggest that the log-logistic model best fits the reconstructed data from the latest published Kaplan-Meier (KM) curves of the BOLERO-2 trial. Results from the regression analyses were confirmed graphically. An equation for transition probabilities was obtained for each arm of the BOLERO-2 trial. In this paper, a tutorial was proposed and used to estimate the transition probabilities for model-based economic evaluation, based on the results of the final PFS analysis of the BOLERO-2 trial in mBC. The results of our study can serve as a basis for any model

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.

Spaced-retrieval effects on name-face recognition in older adults with probable Alzheimer's disease.

PubMed

Hawley, Karri S; Cherry, Katie E

2004-03-01

Six older adults with probable Alzheimer's disease (AD) were trained to recall a name-face association using the spaced-retrieval method. We administered six training sessions over a 2-week period. On each trial, participants selected a target photograph and stated the target name, from eight other photographs, at increasingly longer retention intervals. Results yielded a positive effect of spaced-retrieval training for name-face recognition. All participants were able to select the target photograph and state the target's name for longer periods of time within and across training sessions. A live-person transfer task was administered to determine whether the name-face association, trained by spaced-retrieval, would transfer to a live person. Half of the participants were able to call the live person by the correct name. These data provide initial evidence that spaced-retrieval training can aid older adults with probable AD in recall of a name-face association and in transfer of that association to an actual person.

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.

Survival analysis of adult patients with ALL in Mexico City: first report from the Acute Leukemia Workgroup (ALWG) (GTLA).

PubMed

Crespo-Solis, Erick; Espinosa-Bautista, Karla; Alvarado-Ibarra, Martha; Rozen-Fuller, Etta; Pérez-Rocha, Fernando; Nava-Gómez, Chantal; Ortiz-Zepeda, Maricela; Álvarez-Vera, José Luis; Ramos-Peñafiel, Christian Omar; Meillón-García, Luis Antonio; Rodríguez-Rodríguez, Sergio; Pomerantz-Okon, Alan; Turrubiates-Hernández, Francisco Javier; Demichelis-Gómez, Roberta

2018-06-01

Acute lymphoblastic leukemia (ALL) is a hematologic malignancy characterized by the clonal expansion of hematopoietic lymphoid progenitors. With new target therapies, the survival of adults with ALL has improved in the past few decades. Unfortunately, there are no large ALL patient series in many Latin American countries. Data from the Acute Leukemia Workgroup that includes five Mexico City referral centers were used. Survival was estimated for adult patients with ALL during 2009-2015. In total, 559 adults with ALL were included. The median age was 28 years; 67% were classified into the adolescent and young adult group. Cytogenetic information was available in 54.5% of cases. Of the 305 analyzed cases, most had a normal caryotype (70.5%) and Philadelphia-positive was present in 16.7%. The most commonly used treatment regimen was hyper-CVAD. In approximately 20% of cases, there was considerable delay in the administration of chemotherapy. Primarily refractory cases accounted for 13.1% of patients. At the time of analysis, 26.7% of cases had survived. The 3-year overall survival was 22.1%. The main cause of death was disease progression in 228 (55.6%). Clinical and public health strategies are needed to improve diagnosis, treatment and survivorship care for adult with ALL. This multicentric report represents the largest series in Mexico of adult ALL patients in which a survival analysis and risk identification were obtained. © 2018 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Respiratory disease, behavior, and survival of mountain goat kids

USGS Publications Warehouse

Blanchong, Julie A.; Anderson, Christopher A.; Clark, Nicholas J.; Klaver, Robert W.; Plummer, Paul J.; Cox, Mike; Mcadoo, Caleb; Wolff, Peregrine L.

2018-01-01

Bacterial pneumonia is a threat to bighorn sheep (Ovis canadensis) populations. Bighorn sheep in the East Humboldt Mountain Range (EHR), Nevada, USA, experienced a pneumonia epizootic in 2009–2010. Testing of mountain goats (Oreamnos americanus) that were captured or found dead on this range during and after the epizootic detected bacteria commonly associated with bighorn sheep pneumonia die‐offs. Additionally, in years subsequent to the bighorn sheep epizootic, the mountain goat population had low kid:adult ratios, a common outcome for bighorn sheep populations that have experienced a pneumonia epizootic. We hypothesized that pneumonia was present and negatively affecting mountain goat kids in the EHR. From June–August 2013–2015, we attempted to observe mountain goat kids with marked adult females in the EHR at least once per week to document signs of respiratory disease; identify associations between respiratory disease, activity levels, and subsequent disappearance (i.e., death); and estimate weekly survival. Each time we observed a kid with a marked adult female, we recorded any signs of respiratory disease and collected behavior data that we fit to a 3‐state discrete hidden Markov model (HMM) to predict a kid's state (active vs. sedentary) and its probability of disappearing. We first observed clinical signs of respiratory disease in kids in late July–early August each summer. We observed 8 of 31 kids with marked adult females with signs of respiratory disease on 13 occasions. On 11 of these occasions, the HMM predicted that kids were in the sedentary state, which was associated with increased probability of subsequent death. We estimated overall probability of kid survival from June–August to be 0.19 (95% CI = 0.08–0.38), which was lower than has been reported in other mountain goat populations. We concluded that respiratory disease was present in the mountain goat kids in the EHR and negatively affected their activity levels and survival

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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.more » 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.« less

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.

Genomic analysis of adult B-ALL identifies potential markers of shorter survival.

PubMed

Patel, Shiven; Mason, Clinton C; Glenn, Martha J; Paxton, Christian N; South, Sara T; Cessna, Melissa H; Asch, Julie; Cobain, Erin F; Bixby, Dale L; Smith, Lauren B; Reshmi, Shalini; Gastier-Foster, Julie M; Schiffman, Joshua D; Miles, Rodney R

2017-05-01

B lymphoblastic leukemia (B-ALL) in adults has a higher risk of relapse and lower long-term survival than pediatric B-ALL, but data regarding genetic prognostic biomarkers are much more limited for adult patients. We identified 70 adult B-ALL patients from three institutions and performed genome-wide analysis via single nucleotide polymorphism (SNP) arrays on DNA isolated from their initial diagnostic sample and, when available, relapse bone marrow specimens to identify recurring copy number alterations (CNA). As B-cell developmental genes play a crucial role in this leukemia, we assessed such for recurrent deletions in diagnostic and relapse samples. We confirmed previous findings that the most prevalent deletions of these genes occur in CDKN2A, IKZF1, and PAX5, with several others at lower frequencies. Of the 16 samples having paired diagnostic and relapse samples, 5 showed new deletions in these recurrent B-cell related genes and 8 showed abolishment. Deletion of EBF1 heralded a significant negative prognostic impact on relapse free survival in univariate and multivariate analyses. The combination of both a CDKN2A/B deletion and an IKZF1 alteration (26% of cases) also showed a trend toward predicting worse overall survival compared to having only one or neither of these deletions. These findings add to the understanding of genomic influences on this comparably understudied disease cohort that upon further validation may help identify patients who would benefit from upfront treatment intensification. Copyright © 2017 Elsevier Ltd. All rights reserved.

Environmental and ecological conditions at Arctic breeding sites have limited effects on true survival rates of adult shorebirds

USGS Publications Warehouse

Weiser, Emily L.; Lanctot, Richard B.; Brown, Stephen C.; Gates, H. River; Bentzen, Rebecca L.; Bêty, Joël; Boldenow, Megan L.; English, Willow B.; Franks, Samantha E.; Koloski, Laura; Kwon, Eunbi; Lamarre, Jean-Francois; Lank, David B.; Liebezeit, Joseph R.; McKinnon, Laura; Nol, Erica; Rausch, Jennie; Saalfeld, Sarah T.; Senner, Nathan R.; Ward, David H.; Woodard, Paul F.; Sandercock, Brett K.

2018-01-01

Many Arctic shorebird populations are declining, and quantifying adult survival and the effects of anthropogenic factors is a crucial step toward a better understanding of population dynamics. We used a recently developed, spatially explicit Cormack–Jolly–Seber model in a Bayesian framework to obtain broad-scale estimates of true annual survival rates for 6 species of shorebirds at 9 breeding sites across the North American Arctic in 2010–2014. We tested for effects of environmental and ecological variables, study site, nest fate, and sex on annual survival rates of each species in the spatially explicit framework, which allowed us to distinguish between effects of variables on site fidelity versus true survival. Our spatially explicit analysis produced estimates of true survival rates that were substantially higher than previously published estimates of apparent survival for most species, ranging from S = 0.72 to 0.98 across 5 species. However, survival was lower for the arcticolasubspecies of Dunlin (Calidris alpina arcticola; S = 0.54), our only study taxon that migrates through the East Asian–Australasian Flyway. Like other species that use that flyway, arcticola Dunlin could be experiencing unsustainably low survival rates as a result of loss of migratory stopover habitat. Survival rates of our study species were not affected by timing of snowmelt or summer temperature, and only 2 species showed minor variation among study sites. Furthermore, although previous reproductive success, predator abundance, and the availability of alternative prey each affected survival of one species, no factors broadly affected survival across species. Overall, our findings of few effects of environmental or ecological variables suggest that annual survival rates of adult shorebirds are generally robust to conditions at Arctic breeding sites. Instead, conditions at migratory stopovers or overwintering sites might be driving adult survival rates and should be the

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…

Addition of Adult-to-Adult Living Donation to Liver Transplant Programs Improves Survival but at an Increased Cost1-2

PubMed Central

Northup, Patrick G.; Abecassis, Michael M.; Englesbe, Michael J.; Emond, Jean C.; Lee, Vanessa D.; Stukenborg, George J.; Tong, Lan; Berg, Carl L.

2011-01-01

We performed a cost-effectiveness analysis exploring the cost and benefits of LDLT using outcomes data from the Adult to Adult Living Donor Liver Transplantation Cohort Study (A2ALL). A multistage Markov decision analysis model was developed with treatment strategies including medical management only (strategy 1), waiting list with possible deceased donor liver transplant (strategy 2), and waiting list with possible LDLT or DDLT (strategy 3) over ten years. Decompensated cirrhosis with medical management offered 2.0 quality adjusted life years (QALY) survival while costing an average of $65,068, waiting list with possible DDLT offered 4.4 QALY survival and a mean cost $151,613, and waiting list with possible DDLT or LDLT offered 4.9 QALY survival and a mean cost $208,149. Strategy 2 had an incremental cost effectiveness ratio (ICER) of $35,976 over strategy 1 while strategy 3 produced an ICER of $106,788 over strategy 2. On average, strategy 3 cost $47,693 more per QALY than strategy 1. Both DDLT and LDLT are cost-effective compared to medical management of cirrhosis over our ten year study period. The addition of LDLT to a standard waiting list DDLT program is effective at improving recipient survival and preventing waiting list deaths but at a greater cost. PMID:19177435

Life-history implications of large-scale spatial variation in adult survival of black brant (Branta bernicla nigricans)

USGS Publications Warehouse

Sedinger, James S.; Chelgren, Nathan; Lindberg, Mark S.; Obritchkewitch, Tim; Kirk, Morgan T.; Martin, Philip D.; Anderson, Betty A.; Ward, David H.

2002-01-01

We used capture-recapture methods to estimate adult survival rates for adult female Black Brant (Branta bernicla nigricans; hereafter “brant”) from three colonies in Alaska, two on the Yukon-Kuskokwim Delta, and one on Alaska's Arctic coast. Costs of migration and reproductive effort varied among those colonies, enabling us to examine variation in survival in relation to variation in these other variables. We used the Barker model in program MARK to estimate true annual survival for brant from the three colonies. Models allowing for spatial variation in survival were among the most parsimonious models but were indistinguishable from a model with no spatial variation. Point estimates of annual survival were slightly higher for brant from the Arctic (0.90 ± 0.036) than for brant from either Tutakoke River (0.85 ± 0.004) or Kokechik Bay (0.86 ± 0.011). Thus, our survival estimates do not support a hypothesis that the cost of longer migrations or harvest experienced by brant from the Arctic reduced their annual survival relative to brant from the Yukon-Kuskokwim Delta. Spatial variation in survival provides weak support for life-history theory because brant from the region with lower reproductive investment had slightly higher survival.

Disparities in breast cancer tumor characteristics, treatment, time to treatment, and survival probability among African American and white women.

PubMed

Foy, Kevin Chu; Fisher, James L; Lustberg, Maryam B; Gray, Darrell M; DeGraffinreid, Cecilia R; Paskett, Electra D

2018-01-01

African American (AA) women have a 42% higher breast cancer death rate compared to white women despite recent advancements in management of the disease. We examined racial differences in clinical and tumor characteristics, treatment and survival in patients diagnosed with breast cancer between 2005 and 2014 at a single institution, the James Cancer Hospital, and who were included in the Arthur G. James Cancer Hospital and Richard J. Solove Research Institute Cancer Registry in Columbus OH. Statistical analyses included likelihood ratio chi-square tests for differences in proportions, as well as univariate and multivariate Cox proportional hazards regressions to examine associations between race and overall and progression-free survival probabilities. AA women made up 10.2% (469 of 4593) the sample. Average time to onset of treatment after diagnosis was almost two times longer in AA women compared to white women (62.0 days vs 35.5 days, p  < 0.0001). AA women were more likely to report past or current tobacco use, experience delays in treatment, have triple negative and late stage breast cancer, and were less likely to receive surgery, especially mastectomy and reconstruction following mastectomy. After adjustment for confounding factors (age, grade, and surgery), overall survival probability was significantly associated with race (HR = 1.33; 95% CI 1.03-1.72). These findings highlight the need for efforts focused on screening and receipt of prompt treatment among AA women diagnosed with breast cancer.

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

Annual survival and population estimates of Mountain Plovers in Southern Phillips County, Montana

USGS Publications Warehouse

Dinsmore, S.J.; White, Gary C.; Knopf, F.L.

2003-01-01

Information about the demography of declining species is especially relevant to their conservation and future recovery. Knowledge of survival rates and population size can be used to assess long-term viability and population trends, both of which are of interest to conservation biologists. We used capture–recapture techniques to study the demography of Mountain Plovers (Charadrius montanus Townsend) in southern Phillips County, Montana, USA, in 1995–2000. We used the robust design to estimate annual survival (φ), conditional capture (p and r) and recapture (c) probabilities, and the annual population size (N) in the presence of temporary emigration. The results support age-specific differences in annual survival that are a function of juvenile body mass and are correlated with the area occupied by prairie dogs. Body mass had a positive effect on juvenile survival; the slope coefficient for the additive effect of body mass on juvenile survival was 0.77 (95% ci = 0.25, 1.28) on a logit scale. A measure of plover habitat (the area occupied by prairie dogs) appeared to have no effect on survival; the slope coefficient for the additive effect of area occupied by prairie dogs on survival was –0.00004 (95% ci = –0.00003, –0.0001) on a logit scale. Estimated annual apparent survival rates were 0.46–0.49 for juveniles and 0.68 for adult plovers. Using these estimates, the life span of a Mountain Plover was 1.92 ± 0.17 years (mean ± 1 se) from time of capture as a chick. Resighting rates positively influenced capture probabilities; the slope coefficient for the additive resighting effect was –0.49 (95% ci = –0.86, –0.11) on a logit scale. The size of this adult Mountain Plover population was estimated at 95–180 adults annually. Population size closely tracked annual changes in the area occupied by black-tailed prairie dogs, with both plovers and prairie dogs rapidly recovering from an outbreak of sylvatic plague in the mid-1990s. Given the low annual

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.

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.

Adults surviving lung cancer two or more years: A systematic review.

PubMed

Rhea, Deborah J; Lockwood, Suzy

Lung cancer has had a low survival rate throughout the years. Some studies have shown that psychological variables such as hardiness and resiliency may play a role in the meaningfulness of survival among lung cancer patients. The objective of this systematic review was to synthesize the best available evidence on the experiences of surviving lung cancer (including psychological/affective well-being dimensions such as resiliency, optimism, quality of life, and coping strategies) in adults over the age of 18, two or more years after diagnosis. The review considered adults (18 years and older) who have survived lung cancer two or more years post diagnosis.The review included studies that examined the experiences (including psychological/affective well-being dimensions such as resiliency, optimism, quality of life, and coping strategies) of surviving lung cancer two or more years post diagnosis.The review considered patients' experiences of surviving lung cancer post two years diagnosis, including the examination of specific psychological/affective well-being aspects such as resiliency, optimism, quality of life and coping strategies.The review included quantitative descriptive studies and qualitative studies. A search for published and unpublished studies in English language from January 1999 through December 2010 was undertaken in multiple databases including MEDLINE, CINAHL, ProQuest and Psyc INFO. Assessment of methodological quality of studies was undertaken using critical appraisal tools from the Joanna Briggs Institute. Data was extracted using the Joanna Briggs Institute Data Extraction forms. Results were presented in a narrative format as the synthesis of qualitative or quantitative data was not appropriate. 13 studies were included in the review: one mixed methods study (including a qualitative research component) and 12 quantitative studies.The qualitative component of the included mixed methods study identified five findings related to the meaningfulness

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

Survival of adult Red-throated Loons (Gavia stellata) may be linked to marine conditions

USGS Publications Warehouse

Schmutz, Joel A.

2014-01-01

Large variations in the summering population size of Red-throated Loons (Gavia stellata) have occurred in recent decades in Alaska. Little information exists about annual or seasonal survival rates of adult Red-throated Loons. This study used tracking data from satellite transmitters implanted into 33 Red-throated Loons captured on breeding areas in Alaska to estimate annual survival with the sampling effort split between two study periods: 2000–2002 and 2008–2010. Mortality was inferred from transmitted sensor data that indicated body temperature of the Red-throated Loon and voltage of the transmitter's battery. Two definitive mortalities occurred, resulting in an annual survival estimate of 0.920 (SE = 0.054). The fates of two additional Red-throated Loons were ambiguous and, when treated as mortalities, the annual survival estimate was 0.838 (SE = 0.074). All four putative mortalities occurred during the non-breeding season in the early study period. Oceanic conditions, indexed by the Pacific Decadal Oscillation, appeared to differ between the study periods with higher Pacific Decadal Oscillation values associated with the early study period. Given that high values for Pacific Decadal Oscillation were also associated with the large decline of Red-throated Loons observed in Alaska during 1977–1993, this study suggests that survival of adult Red-throated Loons may vary in relation to the state of the marine ecosystem and thus contribute to long-term variation in population trends.

An Instrument for Estimating the 6-Month Survival Probability After Whole-brain Irradiation Alone for Cerebral Metastases from Gynecological Cancer.

PubMed

Janssen, Stefan; Hansen, Heinke C; Schild, Steven E; Rades, Dirk

2018-06-01

Patients with cerebral metastases from gynecological cancer who receive whole-brain irradiation (WBI) alone require personalized therapy. This study contributes to personalized care by creating an instrument to predict 6-month survival probability. In 49 patients, six pre-treatment variables, namely age, Eastern Cooperative Oncology Group performance score (ECOG-PS), primary tumor type, number of cerebral metastases, metastasis outside the brain, and interval between diagnosis of gynecological cancer and WBI, were analyzed for survival. Of the six pre-treatment variables, ECOG-PS was significantly associated with survival (p=0.014) and metastasis outside the brain showed a trend for association (p=0.096). Six-month survival rates divided by 10 resulted in scores of 0, 2 or 7 points for ECOG-PS and of 2 or 7 points for metastasis outside the brain. Scores for individual patients were 2, 4, 7, 9 or 14 points. Three groups were created, those with 2-7, 9 and 14 points, with 6-month survival rates of 10%, 53% and 100%, respectively (p=0.004). An instrument was designed to predict the 6-month survival of patients receiving WBI for cerebral metastases from gynecological cancer and facilitate personalized care. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Prevalence of food sensitization and probable food allergy among adults in India: the EuroPrevall INCO study.

PubMed

Mahesh, P A; Wong, Gary W K; Ogorodova, L; Potts, J; Leung, T F; Fedorova, O; Holla, Amrutha D; Fernandez-Rivas, M; Clare Mills, E N; Kummeling, I; Versteeg, S A; van Ree, R; Yazdanbakhsh, M; Burney, P

2016-07-01

Data are lacking regarding the prevalence of food sensitization and probable food allergy among general population in India. We report the prevalence of sensitization and probable food allergy to 24 common foods among adults from general population in Karnataka, South India. The study was conducted in two stages: a screening study and a case-control study. A total of 11 791 adults in age group 20-54 were randomly sampled from general population in South India and answered a screening questionnaire. A total of 588 subjects (236 cases and 352 controls) participated in the case-control study involving a detailed questionnaire and specific IgE estimation for 24 common foods. A high level of sensitization (26.5%) was observed for most of the foods in the general population, higher than that observed among adults in Europe, except for those foods that cross-react with birch pollen. Most of the sensitization was observed in subjects who had total IgE above the median IgE level. A high level of cross-reactivity was observed among different pollens and foods and among foods. The prevalence of probable food allergy (self-reports of adverse symptoms after the consumption of food and specific IgE to the same food) was 1.2%, which was mainly accounted for cow's milk (0.5%) and apple (0.5%). Very high levels of sensitization were observed for most foods, including those not commonly consumed in the general population. For the levels of sensitization, the prevalence of probable food allergy was low. This disassociation needs to be further explored in future studies. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Long-term survival of beta thalassemia major patients treated with hematopoietic stem cell transplantation compared with survival with conventional treatment.

PubMed

Caocci, Giovanni; Orofino, Maria Grazia; Vacca, Adriana; Piroddi, Antonio; Piras, Eugenia; Addari, Maria Carmen; Caria, Rossella; Pilia, Maria Paola; Origa, Raffaella; Moi, Paolo; La Nasa, Giorgio

2017-12-01

Allogeneic hematopoietic stem cell transplantation (HSCT) in thalassemia remains a challenge. We reported a single-centre case-control study of a large cohort of 516 children and adult patients treated with HSCT or blood transfusion support and iron chelation therapy; 258 patients (median age 12, range 1-45) underwent sibling (67%) or unrelated (33%) HSCT; 97 patients were adults (age ≥ 16 years). The median follow-up after HSCT was 11 years (range 1-30). The conditioning regimen was busulfan (80.6%) or treosulfan-based (19.4%). A cohort of 258 age-sex matched conventionally treated (CT) patients was randomly selected. In transplanted patients the 30-year overall survival (OS) and thalassemia-free survival (TFS) were 82.6 ± 2.7% and 77.8 ± 2.9%, compared to the OS of 85.3 ± 2.7% in CT patients (P = NS); The incidence of grade II-IV acute and chronic graft versus host disease (GvHD) was 23.6% and 12.9% respectively. The probability of rejection was 6.9%. Transplant-related mortality (TRM) (13.8%) was similar to the probability of dying of cardiovascular events in CT patients (12.2%). High-risk Pesaro score (class 3) was associated with lower OS (OR = 1.99, 95% C.I.=1.31-3.03) and TFS (OR = 1.54, 95% C.I.=1.12-2.12). In adult patients, the 23-years OS and TFS after HSCT were 70 ± 5% and 67.3 ± 5%, compared to 71.2 ± 5% of OS in CT (P = NS). Finally, treosulfan was associated with lower risk of acute GvHD (P = .004; OR = 0.28, 95% C.I.=0.12-0.67). In conclusion, the 30-year survival rate of ex-thalassemia patients after HSCT was similar to that expected in CT thalassemia patients, with the vast majority of HSCT survivors cured from thalassemia. © 2017 Wiley Periodicals, Inc.

Inference for the effect of treatment on survival probability in randomized trials with noncompliance and administrative censoring.

PubMed

Nie, Hui; Cheng, Jing; Small, Dylan S

2011-12-01

In many clinical studies with a survival outcome, administrative censoring occurs when follow-up ends at a prespecified date and many subjects are still alive. An additional complication in some trials is that there is noncompliance with the assigned treatment. For this setting, we study the estimation of the causal effect of treatment on survival probability up to a given time point among those subjects who would comply with the assignment to both treatment and control. We first discuss the standard instrumental variable (IV) method for survival outcomes and parametric maximum likelihood methods, and then develop an efficient plug-in nonparametric empirical maximum likelihood estimation (PNEMLE) approach. The PNEMLE method does not make any assumptions on outcome distributions, and makes use of the mixture structure in the data to gain efficiency over the standard IV method. Theoretical results of the PNEMLE are derived and the method is illustrated by an analysis of data from a breast cancer screening trial. From our limited mortality analysis with administrative censoring times 10 years into the follow-up, we find a significant benefit of screening is present after 4 years (at the 5% level) and this persists at 10 years follow-up. © 2011, The International Biometric Society.

Small Numbers, Big Challenges: Adolescent and Young Adult Cancer Incidence and Survival in New Zealand.

PubMed

Ballantine, Kirsten R; Watson, Heidi; Macfarlane, Scott; Winstanley, Mark; Corbett, Robin P; Spearing, Ruth; Stevanovic, Vladimir; Yi, Ma; Sullivan, Michael J

2017-06-01

This study was undertaken to determine cancer survival and describe the unique spectrum of cancers diagnosed among New Zealand's adolescents and young adult (AYA) population. Registrations for 1606 15-24 year olds diagnosed with a new primary malignant tumor between 2000 and 2009 were obtained from the New Zealand Cancer Registry and classified according to AYA diagnostic group and subgroup, age, sex, and prioritized ethnicity. Age-standardized incidence rates (IRs) per million person years and 5-year relative survival ratios were calculated. Cancer incidence was 228.6 per million for adolescents aged 15-19 years and 325.7 per million for young adults aged 20-24 years. Overall IRs were consistent across all ethnic groups but there were unique ethnic differences by tumor group including a higher incidence of bone tumors, carcinoma of the gastrointestinal tract, and gonadal germ cell tumors among Maori, a higher incidence of leukemia among Pacific peoples, and a higher incidence of melanoma among non-Maori/non-Pacific peoples. Five-year relative survival for adolescents (75.1%) and AYA overall (80.6%) appeared poorer than had been achieved in other high-income countries. Maori (69.5%) and Pacific (71.3%) AYA had lower 5-year survival compared to non-Maori/non-Pacific peoples (84.2%). The survival disparities observed require further investigation to identify and address the causes of these inferior outcomes. The newly established AYA Cancer Network Aotearoa has been tasked with improving cancer survival and care and ensuring equality of access for New Zealand AYAs with cancer.

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.

IMPROVEMENT IN SURVIVAL ASSOCIATED WITH ADULT-TO-ADULT LIVING DONOR LIVER TRANSPLANTATION1,2

PubMed Central

Berg, Carl L.; Gillespie, Brenda W.; Merion, Robert M.; Brown, Robert S.; Abecassis, Michael M.; Trotter, James F.; Fisher, Robert A.; Freise, Chris E.; Ghobrial, R. Mark; Shaked, Abraham; Fair, Jeffrey H.; Everhart, James E.

2009-01-01

Background and Aims More than 2000 adult-to-adult living donor liver transplants (LDLT) have been performed in the U.S., yet the potential benefit to liver transplant candidates of undergoing LDLT compared to waiting for deceased donor liver transplant (DDLT) is unknown. The aim of this study was to determine if there is a survival benefit of adult LDLT Methods Adults with chronic liver disease who had a potential living donor evaluated from 1/98 to 2/03 at nine university-based hospitals were analyzed. Starting at the time of a potential donor’s evaluation, we compared mortality after LDLT to mortality among those who remained on the waitlist or received DDLT. Median follow-up was 4.4 years. Comparisons were made by hazard ratios (HR) adjusted for LDLT candidate characteristics at the time of donor evaluation. Results Among 807 potential living donor recipients, 389 received LDLT, 249 received DDLT, 99 died without transplant, and 70 were awaiting transplant at last follow-up. Receipt of LDLT was associated with an adjusted mortality HR of 0.56 (95% confidence interval [CI] 0.42–0.74; P<0.001) relative to candidates who did not receive LDLT. As centers gained greater experience (> 20 LDLT), LDLT benefit was magnified, with a mortality HR of 0.35 (CI 0.23–0.53; P<0.001). Conclusions Adult LDLT was associated with lower mortality than the alternative of waiting for DDLT. This reduction in mortality was magnified as centers gained experience with living donor liver transplantation. This reduction in transplant candidate mortality must be balanced against the risks undertaken by the living donors themselves. PMID:18054553

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

Hyperprolinemic larvae of the drosophilid fly, Chymomyza costata, survive cryopreservation in liquid nitrogen.

PubMed

Kostál, Vladimír; Zahradnícková, Helena; Šimek, Petr

2011-08-09

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.

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…

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.

Academic Facility Utilization and Survival Outcomes in Adult Head and Neck Sarcomas: An NCDB Analysis.

PubMed

Cannon, Richard B; Carpenter, Patrick S; Boothe, Dustin; Buchmann, Luke O; Hunt, Jason P; Lloyd, Shane; Hitchcock, Ying J; Houlton, Jeffrey J; Weis, John R; Shepherd, Hailey M; Monroe, Marcus M

2018-04-01

Objectives To investigate clinicopathologic and treatment factors associated with survival in adult head and neck sarcomas in the National Cancer Database (NCDB). To analyze whether treatment settings and therapies received influence survival outcomes and to compare trends in utilization via an aggregated national data set. Study Design Prospectively gathered data. Setting NCDB. Subjects and Methods The study comprised a total of 6944 adult patients treated for a head and neck sarcoma from January 2004 to December 2013. Overall survival (OS) was the primary outcome. Results Increased age and tumor size, nodal involvement, and poorly differentiated histology had significantly reduced OS ( P < .001). Angiosarcoma, malignant nerve sheath tumor, malignant fibrous histiocytoma, osteosarcoma, and rhabdomyosarcoma histologic subtypes had significantly reduced OS, while liposarcoma, chondrosarcoma, and chordoma had improved OS ( P < .001). Utilization of surgical therapy was associated with improved OS, while positive surgical margins were associated with treatment at a community-based cancer program and had reduced OS ( P < .001). On multivariate analysis, treatment with radiation and/or chemotherapy was not significantly associated with OS; however, primary treatment with definitive chemoradiotherapy had significantly reduced OS. Patients treated at academic/research cancer programs (n = 3874) had significantly improved 5- and 10-year OS (65% and 54%, respectively) when compared with patients treated at community-based cancer programs (n = 3027; 49% and 29%; P < .001). The percentage utilization of these programs (56% vs 44%) did not change over the study period. Conclusion For adult head and neck sarcomas, treatment at an academic/research cancer program was associated with improved survival; however, despite increasing medical specialization, the percentage utilization of these programs for this rare tumor remains constant.

Factors associated with automobile accidents and survival.

PubMed

Kim, Hong Sok; Kim, Hyung Jin; Son, Bongsoo

2006-09-01

This paper develops an econometric model for vehicles' inherent mortality rate and estimates the probability of accidents and survival in the United States. Logistic regression model is used to estimate probability of survival, and censored regression model is used to estimate probability of accidents. The estimation results indicated that the probability of accident and survival are influenced by the physical characteristics of the vehicles involved in the accident, and by the characteristics of the driver and the occupants. Using restrain system and riding in heavy vehicle increased the survival rate. Middle-aged drivers are less susceptible to involve in an accident, and surprisingly, female drivers are more likely to have an accident than male drivers. Riding in powerful vehicles (high horsepower) and driving late night increase the probability of accident. Overall, the driving behavior and characteristics of vehicle does matter and affects the probabilities of having a fatal accident for different types of vehicles.

Survival of translocated sharp-tailed grouse: Temporal threshold and age effects

USGS Publications Warehouse

Mathews, Steven; Coates, Peter S.; Delehanty, David J.

2016-01-01

Context: The Columbian sharp-tailed grouse (Tympanuchus phasianellus columbianus) is a subspecies of conservation concern in the western United States, currently occupying ≤10% of its historic range. Land and management agencies are employing translocation techniques to restore Columbian sharp-tailed grouse (CSTG) populations. However, establishing self-sustaining populations by translocating grouse often is unsuccessful, owing, in part, to low survivorship of translocated grouse following release.Aims: We measured and modelled patterns of CSTG mortality for 150 days following translocation into historic range, to better understand patterns and causes of success or failure in conservation efforts to re-establish grouse populations.Methods: We conducted two independent multi-year translocations and evaluated individual and temporal factors associated with CSTG survival up to 150 days following their release. Both translocations were reintroduction attempts in Nevada, USA, to establish viable populations of CSTG into their historic range.Key results: We observed a clear temporal threshold in survival probability, with CSTG mortality substantially higher during the first 50 days following release than during the subsequent 100 days. Additionally, translocated yearling grouse exhibited higher overall survival (0.669 ± 0.062) than did adults (0.420 ± 0.052) across the 150-day period and higher survival than adults both before and after the 50-day temporal threshold.Conclusions: Translocated CSTG are especially vulnerable to mortality for 50 days following release, whereas translocated yearling grouse are more resistant to mortality than are adult grouse. On the basis of the likelihood of survival, yearling CSTG are better candidates for population restoration through translocation than are adult grouse.Implications: Management actions that ameliorate mortality factors for 50 days following translocation and translocations that employ yearling grouse will

Initial FDG-PET/CT predicts survival in adults Ewing sarcoma family of tumors

PubMed Central

Jamet, Bastien; Carlier, Thomas; Campion, Loic; Bompas, Emmanuelle; Girault, Sylvie; Borrely, Fanny; Ferrer, Ludovic; Rousseau, Maxime; Venel, Yann; Kraeber-Bodéré, Françoise; Rousseau, Caroline

2017-01-01

Purpose The aim of this retrospective study was to determine, at baseline, the prognostic value of different FDG-PET/CT quantitative parameters in a homogenous Ewing Sarcoma Family of Tumors (ESFT) adult population, compared with clinically relevant prognostic factors. Methods Adult patients from 3 oncological centers, all with proved ESFT, were retrospectively included. Quantitative FDG-PET/CT parameters (SUV (maximum, peak and mean), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of the primary lesion of each patient were recorded before treatment, as well as usual clinical prognostic factors (stage of disease, location, tumor size, gender and age). Then, their relation with progression free survival (PFS) and overall survival (OS) was evaluated. Results 32 patients were included. Median age was 21 years (range, 15 to 61). Nineteen patients (59%) were initially metastatic. On multivariate analysis, high SUVmax remained independent predictor of worst OS (p=0.02) and PFS (p=0.019), metastatic disease of worst PFS (p=0.01) and high SUVpeak of worst OS (p=0.01). Optimal prognostic cut-off of SUVpeak was found at 12.5 in multivariate analyses for PFS and OS (p=0.0001). Conclusions FDG-PET/CT, recommended at ESFT diagnosis for initial staging, can be a useful tool for predicting long-term adult patients outcome through semi-quantitative parameters. PMID:29100369

White-tailed deer population dynamics and adult female survival in the presence of a novel predator: Deer Population Dynamics

DOE PAGES

Chitwood, Michael C.; Lashley, Marcus A.; Kilgo, John C.; ...

2015-02-01

Recent localized declines in white-tailed deer ( Odocoileus virginianus) populations in the southeastern United States have been linked to increasing predation pressure from coyotes ( Canis latrans), a novel predator to the region. Studies have documented coyotes as the leading cause of mortality for neonates, and 1 study documented coyotes as a mortality factor for adult females. However, no study has used field-based vital rates to conduct sensitivity analyses or model deer population trajectories under potential harvest or predator removal strategies. We used low, medium, and high values of fawn survival, adult female survival, and fecundity data collected from Fortmore » Bragg Military Installation, North Carolina to demonstrate the current declining population trajectory for deer (λ = 0.905; low λ = 0.788, high λ = 1.003). Consistent with other studies of ungulates, we determined adult female survival was the most sensitive and elastic vital rate. Further, for 3 potential management (“what if”) scenarios, we projected the population for 10 years using estimated vital rates. Reducing adult female harvest (λ = 0.935; low λ = 0.875, high λ = 1.002) and coyote removal (λ = 0.995; low λ = 0.898, high λ = 1.081) reduced the current population decline, whereas combining both approaches (λ = 1.024; low λ = 0.898, high λ = 1.141) resulted in population increases. Our data indicate that for low-density deer populations with heavy predation pressure on neonates, protecting adult females from harvest may not completely offset population declines. Coyote removal might be a necessary strategy because it could possibly increase very low fawn survival, which appears to be the most important vital rate influencing λ in our study. However, managers may have to start with reductions in adult female harvest because coyote removal would have to be continuous and consistently effective, making it an impractical management approach by itself.« less

White-tailed deer population dynamics and adult female survival in the presence of a novel predator: Deer Population Dynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chitwood, Michael C.; Lashley, Marcus A.; Kilgo, John C.

Recent localized declines in white-tailed deer ( Odocoileus virginianus) populations in the southeastern United States have been linked to increasing predation pressure from coyotes ( Canis latrans), a novel predator to the region. Studies have documented coyotes as the leading cause of mortality for neonates, and 1 study documented coyotes as a mortality factor for adult females. However, no study has used field-based vital rates to conduct sensitivity analyses or model deer population trajectories under potential harvest or predator removal strategies. We used low, medium, and high values of fawn survival, adult female survival, and fecundity data collected from Fortmore » Bragg Military Installation, North Carolina to demonstrate the current declining population trajectory for deer (λ = 0.905; low λ = 0.788, high λ = 1.003). Consistent with other studies of ungulates, we determined adult female survival was the most sensitive and elastic vital rate. Further, for 3 potential management (“what if”) scenarios, we projected the population for 10 years using estimated vital rates. Reducing adult female harvest (λ = 0.935; low λ = 0.875, high λ = 1.002) and coyote removal (λ = 0.995; low λ = 0.898, high λ = 1.081) reduced the current population decline, whereas combining both approaches (λ = 1.024; low λ = 0.898, high λ = 1.141) resulted in population increases. Our data indicate that for low-density deer populations with heavy predation pressure on neonates, protecting adult females from harvest may not completely offset population declines. Coyote removal might be a necessary strategy because it could possibly increase very low fawn survival, which appears to be the most important vital rate influencing λ in our study. However, managers may have to start with reductions in adult female harvest because coyote removal would have to be continuous and consistently effective, making it an impractical management approach by itself.« less

Socioeconomic status and survival among older adults with dementia and depression.

PubMed

Chen, Ruoling; Hu, Zhi; Wei, Li; Wilson, Kenneth

2014-06-01

People from lower socioeconomic groups have a higher risk of mortality. The impact of low socioeconomic status on survival among older adults with dementia and depression remains unclear. To investigate the association between socioeconomic status and mortality in people with dementia and late-life depression in China. Using Geriatric Mental Status - Automated Geriatric Examination for Computer Assisted Taxonomy (GMS-AGECAT) we interviewed 2978 people aged ⩾60 years in Anhui, China. We characterised baseline socioeconomic status and risk factors and diagnosed 223 people with dementia and 128 with depression. All-cause mortality was followed up over 5.6 years. Individuals with dementia living in rural areas had a three times greater risk of mortality (multivariate adjusted hazard ratio (HR) = 2.96, 95% CI 1.45-6.04) than those in urban areas, and for those with depression the HR was 4.15 (95% CI 1.59-10.83). There were similar mortality rates when comparing people with dementia with low v. high levels of education, occupation and income, but individuals with depression with low v. high levels had non-significant increases in mortality of 11%, 50% and 55% respectively Older adults with dementia and depression living in rural China had a significantly higher risk of mortality than urban counterparts. Interventions should be implemented in rural areas to tackle survival inequality in dementia and depression. Royal College of Psychiatrists.

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.

Survival of parents and siblings of supercentenarians.

PubMed

Perls, Thomas; Kohler, Iliana V; Andersen, Stacy; Schoenhofen, Emily; Pennington, JaeMi; Young, Robert; Terry, Dellara; Elo, Irma T

2007-09-01

Given previous evidence of familial predisposition for longevity, we hypothesized that siblings and parents of supercentenarians (age >or= 110 years) were predisposed to survival to very old age and that, relative to their birth cohorts, their relative survival probabilities (RSPs) are even higher than what has been observed for the siblings of centenarians. Mean age at death conditional upon survival to ages 20 and 50 and survival probabilities from ages 20 and 50 to higher ages were determined for 50 male and 56 female siblings and 54 parents of 29 supercentenarians. These estimates were contrasted with comparable estimates based on birth cohort-specific mortality experience for the United States and Sweden. Conditional on survival to age 20 years, mean age at death of supercentenarians' siblings was approximately 81 years for men and women. Compared with respective Swedish and U.S. birth cohorts, these estimates were 17%-20% (12-14 years) higher for the brothers and 11%-14% (8-10 years) higher for the sisters. Sisters had a 2.9 times greater probability and brothers had a 4.3 times greater probability of survival from age 20 to age 90. Mothers of supercentenarians had a 5.8 times greater probability of surviving from age 50 to age 90. Fathers also experienced an increased survival probability from age 50 to age 90 of 2.7, but it failed to attain statistical significance. The RSPs of siblings and mothers of supercentenarians revealed a substantial survival advantage and were most pronounced at the oldest ages. The RSP to age 90 for siblings of supercentenarians was approximately the same as that reported for siblings of centenarians. It is possible that greater RSPs are observed for reaching even higher ages such as 100 years, but a larger sample of supercentenarians and their siblings and parents is needed to investigate this possibility.

Racial residential segregation, socioeconomic disparities, and the White-Black survival gap.

PubMed

Popescu, Ioana; Duffy, Erin; Mendelsohn, Joshua; Escarce, José J

2018-01-01

To evaluate the association between racial residential segregation, a prominent manifestation of systemic racism, and the White-Black survival gap in a contemporary cohort of adults, and to assess the extent to which socioeconomic inequality explains this association. This was a cross sectional study of White and Black men and women aged 35-75 living in 102 large US Core Based Statistical Areas. The main outcome was the White-Black survival gap. We used 2009-2013 CDC mortality data for Black and White men and women to calculate age-, sex- and race adjusted White and Black mortality rates. We measured segregation using the Dissimilarity index, obtained from the Manhattan Institute. We used the 2009-2013 American Community Survey to define indicators of socioeconomic inequality. We estimated the CBSA-level White-Black gap in probability of survival using sequential linear regression models accounting for the CBSA dissimilarity index and race-specific socioeconomic indicators. Black men and women had a 14% and 9% lower probability of survival from age 35 to 75 than their white counterparts. Residential segregation was strongly associated with the survival gap, and this relationship was partly, but not fully, explained by socioeconomic inequality. At the lowest observed level of segregation, and with the Black socioeconomic status (SES) assumed to be at the White SES level scenario, the survival gap is essentially eliminated. White-Black differences in survival remain wide notwithstanding public health efforts to improve life expectancy and initiatives to reduce health disparities. Eliminating racial residential segregation and bringing Black socioeconomic status (SES) to White SES levels would eliminate the White-Black survival gap.

Effects of Temperature on Anoplophora glabripennis (Coleoptera: Cerambycidae) Adult Survival, Reproduction, and Egg Hatch

Treesearch

Melody A. Keena

2006-01-01

Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae) is a recently introduced non-native invasive species in North America that has the potential to destroy several tree species in urban and forest habitats. Adult survival, reproduction, and egg hatch of A. glabripennis from two populations (Ravenswood, Chicago, IL, and Bayside, Queens, NY) were evaluated...

Adult survival of Black-legged Kittiwakes Rissa tridactyla in a Pacific colony

USGS Publications Warehouse

Hatch, Scott A.; Roberts, Bay D.; Fadely, Brian S.

1993-01-01

Breeding Black-legged Kittiwakes Rissa tridactyla survived at a mean annual rate of 0.926 in four years at a colony in Alaska. Survival rates observed in sexed males (0.930) and females (0.937) did not differ significantly. The rate of return among nonbreeding Kittiwakes (0.839) was lower than that of known breeders, presumably because more nonbreeders moved away from the study plots where they were marked. Individual nonbreeders frequented sites up to 5 km apart on the same island, while a few established breeders moved up to 2.5 km between years. Mate retention in breeding Kittiwakes averaged 69% in three years. Among pairs that split, the cause of changing mates was about equally divided between death (46%) and divorce (54%). Average adult life expectancy was estimated at 13.0 years. Combined with annual productivity averaging 0.17 chick per nest, the observed survival was insufficient for maintaining population size. Rather, an irregular decline observed in the study colony since 1981 is consistent with the model of a closed population with little or no recruitment. Compared to their Atlantic counterparts, Pacific Kittiwakes have low productivity and high survival. The question arises whether differences reflect phenotypic plasticity or genetically determined variation in population parameters.

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.

Effects of radiomarking on prairie falcons: Attachment failures provide insights about survival

USGS Publications Warehouse

Steenhof, Karen; Bates, Kirk K.; Fuller, Mark R.; Kochert, Michael N.; McKinley, James 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.

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...

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.

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…

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.

Survival Differences among Native-Born and Foreign-Born Older Adults in the United States

PubMed Central

Dupre, Matthew E.; Gu, Danan; Vaupel, James W.

2012-01-01

Background Studies show that the U.S. foreign-born population has lower mortality than the native-born population before age 65. Until recently, the lack of data prohibited reliable comparisons of U.S. mortality by nativity at older ages. This study provides reliable estimates of U.S. foreign-born and native-born mortality at ages 65 and older at the end of the 20th century. Life expectancies of the U.S. foreign born are compared to other developed nations and the foreign-born contribution to total life expectancy (TLE) in the United States is assessed. Methods Newly available data from Medicare Part B records linked with Social Security Administration files are used to estimate period life tables for nearly all U.S. adults aged 65 and older in 1995. Age-specific survival differences and life expectancies are examined in 1995 by sex, race, and place of birth. Results Foreign-born men and women had lower mortality at almost every age from 65 to 100 compared to native-born men and women. Survival differences by nativity were substantially greater for blacks than whites. Foreign-born blacks had the longest life expectancy of all population groups (18.73 [95% confidence interval {CI}, 18.15–19.30] years at age 65 for men and 22.76 [95% CI, 22.28–23.23] years at age 65 for women). The foreign-born population increased TLE in the United States at older ages, and by international comparison, the U.S. foreign born were among the longest-lived persons in the world. Conclusion Survival estimates based on reliable Medicare data confirm that foreign-born adults have longer life expectancy at older ages than native-born adults in the United States. PMID:22615929

Variance estimation when using inverse probability of treatment weighting (IPTW) with survival analysis.

PubMed

Austin, Peter C

2016-12-30

Propensity score methods are used to reduce the effects of observed confounding when using observational data to estimate the effects of treatments or exposures. A popular method of using the propensity score is inverse probability of treatment weighting (IPTW). When using this method, a weight is calculated for each subject that is equal to the inverse of the probability of receiving the treatment that was actually received. These weights are then incorporated into the analyses to minimize the effects of observed confounding. Previous research has found that these methods result in unbiased estimation when estimating the effect of treatment on survival outcomes. However, conventional methods of variance estimation were shown to result in biased estimates of standard error. In this study, we conducted an extensive set of Monte Carlo simulations to examine different methods of variance estimation when using a weighted Cox proportional hazards model to estimate the effect of treatment. We considered three variance estimation methods: (i) a naïve model-based variance estimator; (ii) a robust sandwich-type variance estimator; and (iii) a bootstrap variance estimator. We considered estimation of both the average treatment effect and the average treatment effect in the treated. We found that the use of a bootstrap estimator resulted in approximately correct estimates of standard errors and confidence intervals with the correct coverage rates. The other estimators resulted in biased estimates of standard errors and confidence intervals with incorrect coverage rates. Our simulations were informed by a case study examining the effect of statin prescribing on mortality. © 2016 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd. © 2016 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd.

Ingestion of Bt rice pollen does not reduce the survival or hypopharyngeal gland development of Apis mellifera adults.

PubMed

Wang, Yuanyuan; Dai, Pingli; Chen, Xiuping; Romeis, Jörg; Shi, Jianrong; Peng, Yufa; Li, Yunhe

2017-05-01

Because of its ecological and economic importance, the honey bee Apis mellifera is commonly used to assess the environmental risk of insect-resistant, genetically modified plants. In the present study, feeding-exposure experiments were used to determine whether pollen from transgenic rice harms A. mellifera worker bees. In 1 experiment, the survival and mean acinus diameter of hypopharyngeal glands of adult bees were similar when bees were fed on pollen from Bt rice lines or from a non-Bt rice line, but bee survival was significantly reduced when they received pollen that was mixed with potassium arsenate as a positive control. In a second experiment, bee survival and hypopharyngeal gland development were not reduced when adult bees were fed on non-Bt pollen and a sucrose solution supplemented with Cry2A at 400 µg/g, Cry1C at 50 µg/g, or bovine serum albumin (BSA) at 400 µg/g, but bee survival and hypopharyngeal gland development were reduced when the diet was supplemented with soybean trypsin inhibitor as a positive control. In both experiments, the uptake of Cry proteins by adult bees was confirmed. Overall, the results indicate that the planting of Bt rice lines expressing Cry2A or Cry1C protein poses a negligible risk to A. mellifera worker bees. Environ Toxicol Chem 2017;36:1243-1248. © 2016 SETAC. © 2016 SETAC.

Subjective Probabilities in Household Surveys

PubMed Central

Hurd, Michael D.

2011-01-01

Subjective probabilities are now collected on a number of large household surveys with the objective of providing data to better understand inter-temporal decision making. Comparison of subjective probabilities with actual outcomes shows that the probabilities have considerable predictive power in situations where individuals have considerable private information such as survival and retirement. In contrast the subjective probability of a stock market gain varies greatly across individuals even though no one has private information and the outcome is the same for everyone. An explanation is that there is considerable variation in accessing and processing information. Further, the subjective probability of a stock market gain is considerably lower than historical averages, providing an explanation for the relatively low frequency of stock holding. An important research objective will be to understand how individuals form their subjective probabilities. PMID:21643535

Age, sex and social influences on adult survival in the cooperatively breeding Karoo Scrub-robin

USGS Publications Warehouse

Lloyd, Penn; Martin, Thomas E.; Taylor, Andrew; Braae, Anne; Altwegg, Res

2016-01-01

Among cooperatively breeding species, helpers are hypothesised to increase the survival of breeders by reducing breeder workload in offspring care and increased group vigilance against predators. Furthermore, parental nepotism or other benefits of group living may provide a survival benefit to young that delay dispersal to help. We tested these hypotheses in the Karoo Scrub-robin (Cercotrichas coryphaeus), a long-lived, and facultative cooperatively breeding species in which male helpers make substantial contributions to the care of young. We found that annual breeder survival in the presence of helpers did not differ detectably from breeders without helpers or breeders that lost helpers. Furthermore, helpers did not gain a survival benefit from deferred breeding; apparent survival did not differ detectably between male helpers and male breeders followed from one year old. These results are consistent with other studies suggesting a lack of adult survival benefits among species where breeders do not substantially reduce workloads when helpers are present. They are also consistent with the hypothesis that males that delay dispersal make the ‘best of a bad job’ by helping on their natal territory to gain indirect fitness benefits when they are unable to obtain a territory vacancy nearby.

Survival of Parents and Siblings of Supercentenarians

PubMed Central

Perls, Thomas; Kohler, Iliana V.; Andersen, Stacy; Schoenhofen, Emily; Pennington, JaeMi; Young, Robert; Terry, Dellara; Elo, Irma T.

2011-01-01

Background Given previous evidence of familial predisposition for longevity, we hypothesized that siblings and parents of supercentenarians (age ≥ 110 years) were predisposed to survival to very old age and that, relative to their birth cohorts, their relative survival probabilities (RSPs) are even higher than what has been observed for the siblings of centenarians. Methods Mean age at death conditional upon survival to ages 20 and 50 and survival probabilities from ages 20 and 50 to higher ages were determined for 50 male and 56 female siblings and 54 parents of 29 supercentenarians. These estimates were contrasted with comparable estimates based on birth cohort-specific mortality experience for the United States and Sweden. Results Conditional on survival to age 20 years, mean age at death of supercentenarians’ siblings was ~81 years for men and women. Compared with respective Swedish and U.S. birth cohorts, these estimates were 17%–20% (12–14 years) higher for the brothers and 11%–14% (8–10 years) higher for the sisters. Sisters had a 2.9 times greater probability and brothers had a 4.3 times greater probability of survival from age 20 to age 90. Mothers of supercentenarians had a 5.8 times greater probability of surviving from age 50 to age 90. Fathers also experienced an increased survival probability from age 50 to age 90 of 2.7, but it failed to attain statistical significance. Conclusions The RSPs of siblings and mothers of supercentenarians revealed a substantial survival advantage and were most pronounced at the oldest ages. The RSP to age 90 for siblings of supercentenarians was approximately the same as that reported for siblings of centenarians. It is possible that greater RSPs are observed for reaching even higher ages such as 100 years, but a larger sample of supercentenarians and their siblings and parents is needed to investigate this possibility. PMID:17895443

Heavy quarkonia in a potential model: binding energy, decay width, and survival probability

NASA Astrophysics Data System (ADS)

Srivastava, P. K.; Chaturvedi, O. S. K.; Thakur, Lata

2018-06-01

Recently a lot of progress has been made in deriving the heavy quark potential within a QCD medium. In this article we have considered heavy quarkonium in a hot quark gluon plasma phase. The heavy-quark potential has been modeled properly for short as well as long distances. The potential at long distances is modeled as a QCD string which is screened at the same scale as the Coulomb field. We have numerically solved the 1+1-dimensional Schrodinger equation for this potential and obtained the eigen wavefunction and binding energy for the 1 S and 2 S states of charmonium and bottomonium. Further, we have calculated the decay width and dissociation temperature of quarkonium states in the QCD plasma. Finally, we have used our recently proposed unified model with these new values of decay widths to calculate the survival probability of the various quarkonium states with respect to centrality at relativistic heavy ion collider and large hadron collider energies. This study provides a unified, consistent and comprehensive description of spectroscopic properties of various quarkonium states at finite temperatures along with their nuclear modification factor at different collision energies.

Cognitive-Motor Interference during Walking in Older Adults with Probable Mild Cognitive Impairment

PubMed Central

Klotzbier, Thomas J.; Schott, Nadja

2017-01-01

Although several studies have shown that dual-tasking (DT) mobility is impaired in Alzheimer's disease, studies on the effects of DT conditions in probable Mild Cognitive Impairment (pMCI) have not yielded unequivocal results. The objectives of the study were to (1) examine the effect of a concurrent task on a complex walking task in adults with cognitive impairment; and (2) determine whether the effect varied with different difficulty levels of the concurrent task. Furthermore, the study was designed to evaluate the Trail-Walking Test (TWT) as a potential detection tool for MCI. We examined DT performance in 42 young adults (mean age 23.9 ± 1.98), and 43 older adults (mean age 68.2 ± 6.42). The MoCA was used to stratify the subjects into those with and without pMCI. DT was assessed using the TWT: participants completed 5 trials each of walking along a fixed pathway, stepping on targets with increasing sequential numbers (i.e., 1-2-…-15), and increasing sequential numbers and letters (i.e., 1-A-2-B-3-…-8). Motor and cognitive DT effects (DTE) were calculated for each task. ROC curves were used to distinguish younger and healthy older adults from older adults with pMCI. The TWT showed excellent test-retest reliability across all conditions and groups (ICC : 0.83–0.97). SEM% was also low (<11%) as was the MDC95% (<30%). Within the DT conditions, the pMCI group showed significantly longer durations for all tasks regardless of the cognitive load compared to the younger and the healthy older adults. The motor DTEs were greatest for the complex condition in older adults with pMCI more so than in comparison with younger and healthy older adults. ROC analyses confirmed that only the tasks with higher cognitive load could differentiate older adults with pMCI from controls (area under the curve >0.7, p < 0.05). The TWT is a reliable DT mobility measure in people with pMCI. However, the condition with high cognitive load is more sensitive than the condition with low

Cognitive-Motor Interference during Walking in Older Adults with Probable Mild Cognitive Impairment.

PubMed

Klotzbier, Thomas J; Schott, Nadja

2017-01-01

Although several studies have shown that dual-tasking (DT) mobility is impaired in Alzheimer's disease, studies on the effects of DT conditions in probable Mild Cognitive Impairment (pMCI) have not yielded unequivocal results. The objectives of the study were to (1) examine the effect of a concurrent task on a complex walking task in adults with cognitive impairment; and (2) determine whether the effect varied with different difficulty levels of the concurrent task. Furthermore, the study was designed to evaluate the Trail-Walking Test (TWT) as a potential detection tool for MCI. We examined DT performance in 42 young adults (mean age 23.9 ± 1.98), and 43 older adults (mean age 68.2 ± 6.42). The MoCA was used to stratify the subjects into those with and without pMCI. DT was assessed using the TWT: participants completed 5 trials each of walking along a fixed pathway, stepping on targets with increasing sequential numbers (i.e., 1-2-…-15), and increasing sequential numbers and letters (i.e., 1-A-2-B-3-…-8). Motor and cognitive DT effects (DTE) were calculated for each task. ROC curves were used to distinguish younger and healthy older adults from older adults with pMCI. The TWT showed excellent test-retest reliability across all conditions and groups (ICC : 0.83-0.97). SEM% was also low (<11%) as was the MDC95% (<30%). Within the DT conditions, the pMCI group showed significantly longer durations for all tasks regardless of the cognitive load compared to the younger and the healthy older adults. The motor DTEs were greatest for the complex condition in older adults with pMCI more so than in comparison with younger and healthy older adults. ROC analyses confirmed that only the tasks with higher cognitive load could differentiate older adults with pMCI from controls (area under the curve >0.7, p < 0.05). The TWT is a reliable DT mobility measure in people with pMCI. However, the condition with high cognitive load is more sensitive than the condition with low

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.

Probability Learning: Changes in Behavior Across Time and Development

PubMed Central

Plate, Rista C.; Fulvio, Jacqueline M.; Shutts, Kristin; Green, C. Shawn; Pollak, Seth D.

2017-01-01

Individuals track probabilities, such as associations between events in their environments, but less is known about the degree to which experience—within a learning session and over development—influences people’s use of incoming probabilistic information to guide behavior in real time. In two experiments, children (4–11 years) and adults searched for rewards hidden in locations with predetermined probabilities. In Experiment 1, children (n = 42) and adults (n = 32) changed strategies to maximize reward receipt over time. However, adults demonstrated greater strategy change efficiency. Making the predetermined probabilities more difficult to learn (Experiment 2) delayed effective strategy change for children (n = 39) and adults (n = 33). Taken together, these data characterize how children and adults alike react flexibly and change behavior according to incoming information. PMID:28121026

Milkweed Matters: Monarch Butterfly (Lepidoptera: Nymphalidae) Survival and Development on Nine Midwestern Milkweed Species

PubMed Central

Pocius, V M; Debinski, D M; Pleasants, J M; Bidne, K G; Hellmich, R L; Brower, L P

2017-01-01

Abstract The population of monarch butterflies east of the Rocky Mountains has experienced a significant decline over the past 20 yr. In order to increase monarch numbers in the breeding range, habitat restoration that includes planting milkweed plants is essential. Milkweeds in the genus Asclepias and Cynanchum are the only host plants for larval monarch butterflies in North America, but larval performance and survival across nine milkweeds native to the Midwest is not well documented. We examined development and survival of monarchs from first-instar larval stages to adulthood on nine milkweed species native to Iowa. The milkweeds included Asclepias exaltata (poke milkweed) (Gentianales: Apocynaceae), Asclepias hirtella (tall green milkweed) (Gentianales: Apocynaceae), Asclepias incarnata (swamp milkweed) (Gentianales: Apocynaceae), Asclepias speciosa (showy milkweed) (Gentianales: Apocynaceae), Asclepias sullivantii (prairie milkweed) (Gentianales: Apocynaceae), Asclepias syriaca (common milkweed) (Gentianales: Apocynaceae), Asclepias tuberosa (butterfly milkweed) (Gentianales: Apocynaceae), Asclepias verticillata (whorled milkweed) (Gentianales: Apocynaceae), and Cynanchum laeve (honey vine milkweed) (Gentianales: Apocynaceae). In greenhouse experiments, fewer larvae that fed on Asclepias hirtella and Asclepias sullivantii reached adulthood compared with larvae that fed on the other milkweed species. Monarch pupal width and adult dry mass differed among milkweeds, but larval duration (days), pupal duration (days), pupal mass, pupal length, and adult wet mass were not significantly different. Both the absolute and relative adult lipids were different among milkweed treatments; these differences are not fully explained by differences in adult dry mass. Monarch butterflies can survive on all nine milkweed species, but the expected survival probability varied from 30 to 75% among the nine milkweed species. PMID:28961914

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…

Lower incidence of reoperation with longer shunt survival with adult ventriculoperitoneal shunts placed for hemorrhage-related hydrocephalus.

PubMed

Hoh, Brian L; Lang, Shih-Shan; Ortiz, Michael V; Chi, Yueh-Yun; Lewis, Stephen B; Pincus, David W

2008-07-01

The incidence of reoperation for ventriculoperitoneal shunts (VPS) in adults, although lower than in pediatric patients, is not insignificant. We hypothesize that adult VPS placed for hemorrhage-related hydrocephalus have a lower incidence of reoperation than those placed for other types of hydrocephalus. We retrospectively reviewed all adult (>/= 20 yr) VPS initially placed from February 2001 to August 2006 at the University of Florida. We determined the incidence and time interval to reoperation. Follow-up was conducted by telephone interview and review of medical records. A total of 286 adult VPS were initially placed: 96 (34%) hemorrhage and 190 (66%) nonhemorrhage. A total of 15 (16%) hemorrhage patients underwent 22 shunt reoperations, compared with 50 (27%) nonhemorrhage patients who underwent 82 shunt reoperations (P = 0.0316). A Poisson regression analysis of the number of reoperations, factoring hemorrhage, age, and sex, demonstrated a significantly lower incidence of reoperation in hemorrhage patients (P = 0.0900). A Cox proportional hazards model analysis of time to first reoperation, factoring hemorrhage, age, and sex, demonstrated a significantly longer shunt survival in hemorrhage patients (P = 0.0404). Adult VPS placed for hemorrhage-related hydrocephalus have a significantly lower incidence of reoperation and significantly longer shunt survival. This result may be related to an incidence of transient shunt dependency in patients with hemorrhage-related hydrocephalus. However, the precise mechanism remains unclear.

Factors affecting survival of adult female white-tailed deer after coyote establishment in South Carolina

Treesearch

John C. Kilgo; Mark Vukovich; Michael J. Conroy; H. Scott Ray; Charles Ruth

2016-01-01

Recent evidence from the southeastern United States of high predation rates by coyotes (Canis latrans) on white-tailed deer (Odocoileus virginianus) fawns combined with reports of predation on adult female deer have prompted concern among wildlifemanagers and hunters regarding the effects ondeer populations.We examined survival rates and causes of...

Incidence and survival of adult cancer patients in Taiwan, 2002-2012.

PubMed

Chiang, Chun-Ju; Lo, Wei-Cheng; Yang, Ya-Wen; You, San-Lin; Chen, Chien-Jen; Lai, Mei-Shu

2016-12-01

Little is known about the annual changes in cancer incidence and survival that occurred after the establishment of the long-form cancer registry database in Taiwan. Therefore, this study aimed to investigate the updated incidence and stage-specific relative survival rates (RSRs) among adult cancer patients in Taiwan. Cancer incidence data from 2002 to 2012 were collected using the Taiwan Cancer Registry Database. Age-standardized incidence rates, average annual percent changes (AAPCs), and sex ratios were calculated for adults. Five-year stage-specific RSRs were estimated for cases diagnosed between 2004 and 2008 and were followed up to 2013 for major cancers. The overall age-standardized incidence rates per 100,000 populations increased from 348.39 in 2002 to 401.18 in 2012, and the AAPC was 1.7% (p < 0.05), whereas the male:female ratio was approximately 1:3 during the entire period. Most cancer sites showed a trend of increasing incidence, with the exception of common cancers such as cervix uteri (AAPC = -6.2%, p < 0.05), bladder (AAPC = -2.5%, p < 0.05), stomach (AAPC = -2.4%, p < 0.05), nasopharynx (AAPC = -1.2%, p < 0.05), and liver (AAPC = -1.1%, p < 0.05). The 5-year RSRs for Stage I cancers were greater than 93% for the colon and rectum, female breast, and cervix uteri, whereas RSRs for patients with Stage IV cancers ranged from 2.9% to 38.9%, with patients with liver cancer and those with oral cancer showing the lowest and highest RSRs, respectively. Our study showed increased incidence in most cancers and provided baseline estimates of stage-specific RSRs among the Taiwanese adult population. Continuous surveillance may help politicians to improve health policies and cancer care in Taiwan. Copyright © 2016. Published by Elsevier B.V.

Comparison of Survival at Adult versus Pediatric Treatment Centers for Rare Pediatric Tumors in an Adolescent and Young Adult (AYA) Population in the State of Georgia

PubMed Central

Cash, Thomas; Qayed, Muna; Ward, Kevin C.; Mertens, Ann C.; Rapkin, Louis

2014-01-01

Background The type of treatment center where 15-21-year-old adolescent and young adult (AYA) patients with rare pediatric tumors achieve their best clinical outcome is unknown. Procedure We performed a retrospective analysis using the Georgia Cancer Registry (GCR) of 15-21-year-old patients with a malignant, rare pediatric tumor diagnosed during the period from 2000-2009. Patients were identified as being treated at one of five Georgia pediatric cancer centers or at an adult center. Data were analyzed for 10-year overall survival, patient characteristics associated with death, and patient characteristics present at diagnosis associated with choice of treatment center. Results There was a total of 479 patients in our final study population, of which 379 (79.1%) were treated at an adult center and 100 (20.9%) were treated at a pediatric center. Patients treated at an adult center had a 10-year overall survival of 86% compared to 85% for patients treated at a pediatric center (p= 0.31). Race and poverty were not significantly associated with death. Patients with nasopharyngeal carcinoma (OR=7.38; 95% CI=2.30 – 23.75) and ‘other carcinomas’ (OR=2.64; 95% CI=1.25 – 5.60) were more likely to be treated at a pediatric center. Patients with higher-stage disease (OR=4.24; 95% CI=1.71 – 10.52) and higher poverty (OR=2.32; 95% CI=1.23 – 4.37) were also more likely to be treated at a pediatric center. Conclusion Our data suggest that there is no difference in survival for 15-21-year-old patients with rare pediatric tumors when treated at an adult or pediatric center. PMID:25393593

Advanced techniques for modeling avian nest survival

USGS Publications Warehouse

Dinsmore, S.J.; White, Gary C.; Knopf, F.L.

2002-01-01

Estimation of avian nest survival has traditionally involved simple measures of apparent nest survival or Mayfield constant-nest-survival models. However, these methods do not allow researchers to build models that rigorously assess the importance of a wide range of biological factors that affect nest survival. Models that incorporate greater detail, such as temporal variation in nest survival and covariates representative of individual nests represent a substantial improvement over traditional estimation methods. In an attempt to improve nest survival estimation procedures, we introduce the nest survival model now available in the program MARK and demonstrate its use on a nesting study of Mountain Plovers (Charadrius montanus Townsend) in Montana, USA. We modeled the daily survival of Mountain Plover nests as a function of the sex of the incubating adult, nest age, year, linear and quadratic time trends, and two weather covariates (maximum daily temperature and daily precipitation) during a six-year study (1995–2000). We found no evidence for yearly differences or an effect of maximum daily temperature on the daily nest survival of Mountain Plovers. Survival rates of nests tended by female and male plovers differed (female rate = 0.33; male rate = 0.49). The estimate of the additive effect for males on nest survival rate was 0.37 (95% confidence limits were 0.03, 0.71) on a logit scale. Daily survival rates of nests increased with nest age; the estimate of daily nest-age change in survival in the best model was 0.06 (95% confidence limits were 0.04, 0.09) on a logit scale. Daily precipitation decreased the probability that the nest would survive to the next day; the estimate of the additive effect of daily precipitation on the nest survival rate was −1.08 (95% confidence limits were −2.12, −0.13) on a logit scale. Our approach to modeling daily nest-survival rates allowed several biological factors of interest to be easily included in nest survival models

Survival of adults with systemic autoimmune rheumatic diseases and pulmonary arterial hypertension after lung transplantation.

PubMed

Bernstein, Elana J; Bathon, Joan M; Lederer, David J

2018-05-01

Pulmonary arterial hypertension (PAH) is a major cause of morbidity and mortality in adults with systemic autoimmune rheumatic diseases (ARDs). The aim of this study was to determine whether adults with ARDs and PAH on right-sided heart catheterization (ARD-PAH) have increased mortality following lung transplantation compared with those with PAH not due to an ARD. We conducted a retrospective cohort study of 93 adults with ARD-PAH and 222 adults with PAH who underwent lung transplantation in the USA between 4 May 2005 and 9 March 2015 using data from the United Network for Organ Sharing. We examined associations between diagnosis and survival after lung transplantation using stratified Cox models adjusted for potential confounding recipient factors. Among adults undergoing lung transplantation in the USA, we did not detect a difference in the multivariable-adjusted mortality rate between those with ARD-PAH and those with PAH [hazard ratio 0.75 (95% CI 0.47, 1.19)]. The presence of an ARD was not associated with increased mortality after lung transplantation in adults with PAH.

Probability Learning: Changes in Behavior Across Time and Development.

PubMed

Plate, Rista C; Fulvio, Jacqueline M; Shutts, Kristin; Green, C Shawn; Pollak, Seth D

2018-01-01

Individuals track probabilities, such as associations between events in their environments, but less is known about the degree to which experience-within a learning session and over development-influences people's use of incoming probabilistic information to guide behavior in real time. In two experiments, children (4-11 years) and adults searched for rewards hidden in locations with predetermined probabilities. In Experiment 1, children (n = 42) and adults (n = 32) changed strategies to maximize reward receipt over time. However, adults demonstrated greater strategy change efficiency. Making the predetermined probabilities more difficult to learn (Experiment 2) delayed effective strategy change for children (n = 39) and adults (n = 33). Taken together, these data characterize how children and adults alike react flexibly and change behavior according to incoming information. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

Body Mass Trajectories and Mortality Among Older Adults: A Joint Growth Mixture–Discrete-Time Survival Analysis

PubMed Central

Zajacova, Anna

2014-01-01

Purpose of the Study: The aim of this study was to investigate heterogeneity in body weight trajectories among older adults and their association with mortality risks. Design and Methods: Information on body mass index (BMI) and survival come from nine waves of the Health and Retirement Study, a 16-year survey of adults aged 51–61 at baseline (N = 9,703). We used a sex-stratified joint growth mixture-discrete time survival model to characterize BMI trajectory groups and their associated mortality. Results: Three distinct classes of BMI trajectories were identified: “stable overweight,” “obese gaining,” and “obese losing.” Relative to the stable overweight class, which comprised about 90% of the sample, the obese gaining class had approximately 50% higher mortality risk; the highest mortality was found in the obese losing category (OR > 2.7, p < .001). The results were similar for men and women. Implications: The findings highlight substantial heterogeneity in weight trajectories of older Americans, as well as large survival differentials across the classes. The direction of weight changes appears inextricably linked to the overall BMI level in terms of predicting older adults’ longevity. Weight loss is associated with particularly high mortality risk even when the typical BMI change is from obesity to overweight. PMID:23355450

Measuring change in health status of older adults at the population level: the transition probability model.

PubMed

Moineddin, Rahim; Nie, Jason X; Wang, Li; Tracy, C Shawn; Upshur, Ross E G

2010-11-09

The current demographic transition will lead to increasing demands on health services. However, debate exists as to the role age plays relative to co-morbidity in terms of health services utilization. While age has been identified as a critical factor in health services utilization, health services utilization is not simply an outcome of ill health, nor is it an inevitable outcome of aging. Most data on health service utilization studies assess utilization at one point in time, and does not examine transitions in health service utilization. We sought to measure health services utilization and to investigate patterns in the transition of levels of utilization and outcomes associated with different levels of utilization. We conducted a population-based retrospective cohort study of all Ontario residents aged 65+ eligible for public healthcare coverage from January 1998-December 2006. The main outcome measure was total number of utilization events. The total is computed by summing, on a per annum basis, the number of family physician visits, specialist visits, Emergency Department visits, drug claims, lab claims, X-rays, CT scans, MRI scans, and inpatient admissions. Three categories of utilization were created: low, moderate, and high. There is heterogeneity in health services utilization across the late lifespan. Utilization increased consistently in the 9-year study period. The probability of remaining at the high utilization category when the person was in the high category the previous year was more than 0.70 for both males and females and for all age groups. Overall healthcare utilization increases more rapidly among the high users compared to the low users. There was negligible probability for moving from high to low utilization category. Probability of death increased exponentially as age increased. Older adults in the low utilization category had the lowest probability of death. The number of male nonagenarians increased more rapidly than female nonagenarians

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

Correlates of engaging in survival sex among homeless youth and young adults.

PubMed

Walls, N Eugene; Bell, Stephanie

2011-09-01

Using a sample of 1,625 homeless youth and young adults aged 10 to 25 from 28 different states in the United States, this study examines the correlates of having engaged in survival sex. Findings suggest that differences exist based on demographic variables (gender, age, race, and sexual orientation), lifetime drug use (inhalants, Valium™, crack cocaine, alcohol, Coricidin™, and morphine), recent drug use (alcohol, ecstasy, heroin, and methamphetamine), mental health variables (suicide attempts, familial history of substance use, and having been in substance abuse treatment), and health variables (sharing needles and having been tested for HIV). In addition to replicating previous findings, this study's findings suggest that African American youth; gay, lesbian, or bisexual youth; and youth who had been tested for HIV were significantly more likely to have engaged in survival sex than White, heterosexual youth, and youth who had not been tested for HIV, respectively. Implications for interventions with youth and suggestions for future research are discussed.

Milkweed Matters: Monarch Butterfly (Lepidoptera: Nymphalidae) Survival and Development on Nine Midwestern Milkweed Species.

PubMed

Pocius, V M; Debinski, D M; Pleasants, J M; Bidne, K G; Hellmich, R L; Brower, L P

2017-10-01

The population of monarch butterflies east of the Rocky Mountains has experienced a significant decline over the past 20 yr. In order to increase monarch numbers in the breeding range, habitat restoration that includes planting milkweed plants is essential. Milkweeds in the genus Asclepias and Cynanchum are the only host plants for larval monarch butterflies in North America, but larval performance and survival across nine milkweeds native to the Midwest is not well documented. We examined development and survival of monarchs from first-instar larval stages to adulthood on nine milkweed species native to Iowa. The milkweeds included Asclepias exaltata (poke milkweed) (Gentianales: Apocynaceae), Asclepias hirtella (tall green milkweed) (Gentianales: Apocynaceae), Asclepias incarnata (swamp milkweed) (Gentianales: Apocynaceae), Asclepias speciosa (showy milkweed) (Gentianales: Apocynaceae), Asclepias sullivantii (prairie milkweed) (Gentianales: Apocynaceae), Asclepias syriaca (common milkweed) (Gentianales: Apocynaceae), Asclepias tuberosa (butterfly milkweed) (Gentianales: Apocynaceae), Asclepias verticillata (whorled milkweed) (Gentianales: Apocynaceae), and Cynanchum laeve (honey vine milkweed) (Gentianales: Apocynaceae). In greenhouse experiments, fewer larvae that fed on Asclepias hirtella and Asclepias sullivantii reached adulthood compared with larvae that fed on the other milkweed species. Monarch pupal width and adult dry mass differed among milkweeds, but larval duration (days), pupal duration (days), pupal mass, pupal length, and adult wet mass were not significantly different. Both the absolute and relative adult lipids were different among milkweed treatments; these differences are not fully explained by differences in adult dry mass. Monarch butterflies can survive on all nine milkweed species, but the expected survival probability varied from 30 to 75% among the nine milkweed species. © The Author 2017. Published by Oxford University Press on behalf

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.

Risk-adjusted sequential probability ratio tests: applications to Bristol, Shipman and adult cardiac surgery.

PubMed

Spiegelhalter, David; Grigg, Olivia; Kinsman, Robin; Treasure, Tom

2003-02-01

To investigate the use of the risk-adjusted sequential probability ratio test in monitoring the cumulative occurrence of adverse clinical outcomes. Retrospective analysis of three longitudinal datasets. Patients aged 65 years and over under the care of Harold Shipman between 1979 and 1997, patients under 1 year of age undergoing paediatric heart surgery in Bristol Royal Infirmary between 1984 and 1995, adult patients receiving cardiac surgery from a team of cardiac surgeons in London,UK. Annual and 30-day mortality rates. Using reasonable boundaries, the procedure could have indicated an 'alarm' in Bristol after publication of the 1991 Cardiac Surgical Register, and in 1985 or 1997 for Harold Shipman depending on the data source and the comparator. The cardiac surgeons showed no significant deviation from expected performance. The risk-adjusted sequential probability test is simple to implement, can be applied in a variety of contexts, and might have been useful to detect specific instances of past divergent performance. The use of this and related techniques deserves further attention in the context of prospectively monitoring adverse clinical outcomes.

Nutritional status and survival among old adults: an 11-year population-based longitudinal study.

PubMed

Shakersain, B; Santoni, G; Faxén-Irving, G; Rizzuto, D; Fratiglioni, L; Xu, W

2016-03-01

The impact of nutritional status on survival among community-dwelling older adults is unclear. We aimed to investigate the prevalence and association of poor nutritional status, including malnutrition and risk for malnutrition defined by the Mini-Nutritional Assessment-Short Form (MNA-SF) with survival, and to explore the role of relevant biomarkers (hemoglobin, albumin and C-reactive protein) in this association. This study included 3041 participants aged ⩾ 60 in the Swedish National study on Aging and Care-Kungsholmen. On the basis of the total score in MNA-SF, nutritional status for each participant was assessed as normal (score 12-14), risk for malnutrition (8-11) or malnutrition (<8). Over an 11-year follow-up, survival status was observed. Data were analysed using logistic regression, flexible parametric survival and Laplace models. Of all the participants, 51 (1.7%) had malnutrition and 751 (24.7%) were at risk for malnutrition. The multi-adjusted hazard ratio (95% confidence interval) of mortality was 2.40 (1.56-3.67; P<0.001) for malnutrition and 1.49 (1.29-1.71; P<0.001) for risk for malnutrition. The median ages at death of participants with malnutrition and risk for malnutrition were ~3 and 1.5 years shorter than those with normal nutritional status, respectively, whereas malnutrition or risk for malnutrition together with abnormal biomarker (hemoglobin and albumin) levels was related to 1 year more shortened survival. Malnutrition and risk for malnutrition are highly prevalent and significantly associated with a shorter survival. Poor nutritional status in combination with abnormalities in the biomarkers is associated with even more shortened survival.

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.

Survival Rates of Adults With Acute Lymphoblastic Leukemia in a Low-Income Population: A Decade of Experience at a Single Institution in Mexico.

PubMed

Jaime-Pérez, José Carlos; Jiménez-Castillo, Raúl Alberto; Herrera-Garza, José Luis; Gutiérrez-Aguirre, Homero; Marfil-Rivera, Luis Javier; Gómez-Almaguer, David

2017-01-01

The therapeutic progress for adults with acute lymphoblastic leukemia (ALL) has been slow, with a 5-year survival of 30% to 45% in developed countries. Scarce information is available regarding the treatment and survival rates from nonindustrialized populations. In the present study, the characteristics of adults with ALL at a single institution were documented. The clinical files of patients aged ≥ 18 years who had been diagnosed with ALL from 2005 to 2015 at a reference center in Mexico were scrutinized. Overall survival (OS) and event-free survival (EFS) were determined using the Kaplan-Meier method. The hazard ratios for death and relapse were estimated using Cox regression analysis. A total of 94 adults were included. Their median age was 33 years; 69 (73.4%) had high-risk and 25 (26.6%) had standard-risk ALL. Of the 94 patients, 67 (71.3%) achieved complete remission (CR), 20 (21.3%) experienced disease resistance, and 7 (7.4%) died early during induction to remission, mainly of sepsis. The 5-year EFS and OS was 23.4% and 31.1% for the whole group and 24.9% and 38.9% for patients who achieved CR, respectively. Of the 94 patients, 50 (43.9%) died of sepsis or disease progression. Relapse developed in 43 patients (45.7%). The median survival after relapse was 6.93 months. Bone marrow was the most frequent site of relapse (21 patients [48.8%]) and conferred a significantly lower 5-year OS of 16.4%. Adults with ALL in Mexico had high-risk characteristics and an increased relapse rate; however, the OS after CR was similar to the greatest achieved in developed countries, suggesting that a threshold for curing adult ALL with current therapeutic strategies has been reached. Copyright © 2016 Elsevier Inc. All rights reserved.

PARP activity and inhibition in fetal and adult oligodendrocyte precursor cells: Effect on cell survival and differentiation.

PubMed

Baldassarro, Vito A; Marchesini, Alessandra; Giardino, Luciana; Calzà, Laura

2017-07-01

Poly (ADP-ribose) polymerase (PARP) family members are ubiquitously expressed and play a key role in cellular processes, including DNA repair and cell death/survival balance. Accordingly, PARP inhibition is an emerging pharmacological strategy for cancer and neurodegenerative diseases. Consistent evidences support the critical involvement of PARP family members in cell differentiation and phenotype maturation. In this study we used an oligodendrocyte precursor cells (OPCs) enriched system derived from fetal and adult brain to investigate the role of PARP in OPCs proliferation, survival, and differentiation. The PARP inhibitors PJ34, TIQ-A and Olaparib were used as pharmacological tools. The main results of the study are: (i) PARP mRNA expression and PARP activity are much higher in fetal than in adult-derived OPCs; (ii) the culture treatment with PARP inhibitors is cytotoxic for OPCs derived from fetal, but not from adult, brain; (iii) PARP inhibition reduces cell number, according to the inhibitory potency of the compounds; (iv) PARP inhibition effect on fetal OPCs is a slow process; (v) PARP inhibition impairs OPCs maturation into myelinating OL in fetal, but not in adult cultures, according to the inhibitory potency of the compounds. These results have implications for PARP-inhibition therapies for diseases and lesions of the central nervous system, in particular for neonatal hypoxic/ischemic encephalopathy. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Does framing of cancer survival affect perceived value of care? A willingness-to-pay survey of US residents.

PubMed

Lin, Pei-Jung; Concannon, Thomas W; Greenberg, Dan; Cohen, Joshua T; Rossi, Gregory; Hille, Jeffrey; Auerbach, Hannah R; Fang, Chi-Hui; Nadler, Eric S; Neumann, Peter J

2013-08-01

To investigate the relationship between the framing of survival gains and the perceived value of cancer care. Through a population-based survey of 2040 US adults, respondents were randomized to one of the two sets of hypothetical scenarios, each of which described the survival benefit for a new treatment as either an increase in median survival time (median survival), or an increase in the probability of survival for a given length of time (landmark survival). Each respondent was presented with two randomly selected scenarios with different prognosis and survival improvements, and asked about their willingness to pay (WTP) for the new treatments. Predicted WTP increased with survival benefits and respondents' income, regardless of how survival benefits were described. Framing therapeutic benefits as improvements in landmark rather than median time survival increased the proportion of the population willing to pay for that gain by 11-35%, and the mean WTP amount by 42-72% in the scenarios we compared. How survival benefits are described may influence the value people place on cancer care.

Using thermal inactivation kinetics to calculate the probability of extreme spore longevity: implications for paleomicrobiology and lithopanspermia.

PubMed

Nicholson, Wayne L

2003-12-01

Thermal inactivation kinetics with extrapolation were used to model the survival probabilities of spores of various Bacillus species over time periods of millions of years at the historical ambient temperatures (25-40 degrees C) encountered within the 250 million-year-old Salado formation, from which the putative ancient spore-forming bacterium Salibacillus marismortui strain 2-9-3 was recovered. The model indicated extremely low-to-moderate survival probabilities for spores of mesophiles. but surprisingly high survival probabilities for thermophilic spores. The significance of the results are discussed in terms of the survival probabilities of (i) terrestrial spores in ancient geologic samples and (ii) spores transported between planets within impact ejecta.

Using Thermal Inactivation Kinetics to Calculate the Probability of Extreme Spore Longevity: Implications for Paleomicrobiology and Lithopanspermia

NASA Astrophysics Data System (ADS)

Nicholson, Wayne L.

2003-12-01

Thermal inactivation kinetics with extrapolation were used to model the survival probabilities of spores of various Bacillus species over time periods of millions of years at the historical ambient temperatures (25-40 °) encountered within the 250 million-year-old Salado formation, from which the putative ancient spore-forming bacterium Salibacillus marismortui strain 2-9-3 was recovered. The model indicated extremely low-to-moderate survival probabilities for spores of mesophiles, but surprisingly high survival probabilities for thermophilic spores. The significance of the results are discussed in terms of the survival probabilities of (i) terrestrial spores in ancient geologic samples and (ii) spores transported between planets within impact ejecta.

Unrelated umbilical cord blood transplant for adult acute lymphoblastic leukemia in first and second complete remission: a comparison with allografts from adult unrelated donors

PubMed Central

Marks, David I.; Woo, Kwang Ahn; Zhong, Xiaobo; Appelbaum, Frederick R.; Bachanova, Veronika; Barker, Juliet N.; Brunstein, Claudio G.; Gibson, John; Kebriaei, Partow; Lazarus, Hillard M.; Olsson, Richard; Perales, Miguel-Angel; Pidala, Joseph; Savani, Bipin; Rocha, Vanderson; Eapen, Mary

2014-01-01

Allogeneic hematopoietic cell transplantation has an established role in the treatment of adults with acute lymphoblastic leukemia whose survival when recipients of grafts from adult unrelated donors approaches that of recipients of grafts from sibling donors. Our aim was to determine the role of mismatched unrelated cord blood grafts in transplantation for 802 adults with acute lymphoblastic leukemia in first or second complete remission. Using Cox regression we compared outcomes after 116 mismatched single or double cord blood transplants, 546 peripheral blood progenitor cell transplants and 140 bone marrow transplants. The characteristics of the recipients and their diseases were similar except cord blood recipients were younger, more likely to be non-Caucasians and more likely to have a low white blood cell count at diagnosis. There were differences in donor-recipient human leukocyte antigen-match depending on the source of the graft. Most adult donor transplants were matched at the allele-level considering human leukocyte antigens-A, -B, -C and –DRB1. In contrast, most cord blood transplants were mismatched and considered antigen-level matching; 57% were mismatched at two loci and 29% at one locus whereas only 29% of adult donor transplants were mismatched at one locus and none at two loci. There were no differences in the 3-year probabilities of survival between recipients of cord blood (44%), matched adult donor (44%) and mismatched adult donor (43%) transplants. Cord blood transplants engrafted slower and were associated with less grade 2–4 acute but similar chronic graft-versus-host disease, relapse, and transplant-related mortality. The survival of cord blood graft recipients was similar to that of recipients of matched or mismatched unrelated adult donor grafts and so cord blood should be considered a valid alternative source of stem cells for adults with acute lymphoblastic leukemia in the absence of a matched unrelated adult donor. PMID:24056817

Fracture strength and probability of survival of narrow and extra-narrow dental implants after fatigue testing: In vitro and in silico analysis.

PubMed

Bordin, Dimorvan; Bergamo, Edmara T P; Fardin, Vinicius P; Coelho, Paulo G; Bonfante, Estevam A

2017-07-01

To assess the probability of survival (reliability) and failure modes of narrow implants with different diameters. For fatigue testing, 42 implants with the same macrogeometry and internal conical connection were divided, according to diameter, as follows: narrow (Ø3.3×10mm) and extra-narrow (Ø2.9×10mm) (21 per group). Identical abutments were torqued to the implants and standardized maxillary incisor crowns were cemented and subjected to step-stress accelerated life testing (SSALT) in water. The use-level probability Weibull curves, and reliability for a mission of 50,000 and 100,000 cycles at 50N, 100, 150 and 180N were calculated. For the finite element analysis (FEA), two virtual models, simulating the samples tested in fatigue, were constructed. Loading at 50N and 100N were applied 30° off-axis at the crown. The von-Mises stress was calculated for implant and abutment. The beta (β) values were: 0.67 for narrow and 1.32 for extra-narrow implants, indicating that failure rates did not increase with fatigue in the former, but more likely were associated with damage accumulation and wear-out failures in the latter. Both groups showed high reliability (up to 97.5%) at 50 and 100N. A decreased reliability was observed for both groups at 150 and 180N (ranging from 0 to 82.3%), but no significant difference was observed between groups. Failure predominantly involved abutment fracture for both groups. FEA at 50N-load, Ø3.3mm showed higher von-Mises stress for abutment (7.75%) and implant (2%) when compared to the Ø2.9mm. There was no significant difference between narrow and extra-narrow implants regarding probability of survival. The failure mode was similar for both groups, restricted to abutment fracture. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nanocerium oxide increases the survival of adult rod and cone photoreceptor in culture by abrogating hydrogen peroxide-induced oxidative stress.

PubMed

Bhargava, Neelima; Shanmugaiah, Vellasamy; Saxena, Manav; Sharma, Manish; Sethy, Niroj Kumar; Singh, Sushil Kumar; Balakrishnan, Karuppiah; Bhargava, Kalpana; Das, Mainak

2016-09-16

In vitro cell culture system for adult rod and cone photoreceptor (PR) is an effective and economical model for screening drug candidates against all kinds of age related retinal blindness. Interestingly, adult PR cells have a limited survival in the culture system, thus preventing full exploitation of this in vitro approach for drug screening applications. The limited survival of the adult PR cells in culture is due to their inherently high oxidative stress and photic injury. Mixed valence-state ceria nanoparticles have the ability to scavenge free radicals and reduce oxidative stress. Here, ceria nanoparticles of 5-10 nm dimensions have been synthesized, possessing dual oxidation state (+3 and +4) as evident from x-ray photoelectron spectroscopy and exhibiting real time reduction of hydrogen peroxide (H 2 O 2 ) as quantified by absorbance spectroscopy and cyclic voltammogram analysis. Using flow cytometry and cell culture assay, it has been shown that, upon one time addition of 10 nM of nanoceria in the PR culture of the 18 months old adult common carp (Cyprinus carpio) at the time of plating the cells, the oxidative stress caused due to hydrogen peroxide assault could be abrogated. A further single application of nanoceria significantly increases the survival of these fragile cells in the culture, thus paving way for developing a more robust photoreceptor culture model to study the aging photoreceptor cells in a defined condition.

Cell survival fraction estimation based on the probability densities of domain and cell nucleus specific energies using improved microdosimetric kinetic models.

PubMed

Sato, Tatsuhiko; Furusawa, Yoshiya

2012-10-01

Estimation of the survival fractions of cells irradiated with various particles over a wide linear energy transfer (LET) range is of great importance in the treatment planning of charged-particle therapy. Two computational models were developed for estimating survival fractions based on the concept of the microdosimetric kinetic model. They were designated as the double-stochastic microdosimetric kinetic and stochastic microdosimetric kinetic models. The former model takes into account the stochastic natures of both domain and cell nucleus specific energies, whereas the latter model represents the stochastic nature of domain specific energy by its approximated mean value and variance to reduce the computational time. The probability densities of the domain and cell nucleus specific energies are the fundamental quantities for expressing survival fractions in these models. These densities are calculated using the microdosimetric and LET-estimator functions implemented in the Particle and Heavy Ion Transport code System (PHITS) in combination with the convolution or database method. Both the double-stochastic microdosimetric kinetic and stochastic microdosimetric kinetic models can reproduce the measured survival fractions for high-LET and high-dose irradiations, whereas a previously proposed microdosimetric kinetic model predicts lower values for these fractions, mainly due to intrinsic ignorance of the stochastic nature of cell nucleus specific energies in the calculation. The models we developed should contribute to a better understanding of the mechanism of cell inactivation, as well as improve the accuracy of treatment planning of charged-particle therapy.

Apparent annual survival estimates of tropical songbirds better reflect life history variation when based on intensive field methods

USGS Publications Warehouse

Martin, Thomas E.; Riordan, Margaret M.; Repin, Rimi; Mouton, James C.; Blake, William M.

2017-01-01

AimAdult survival is central to theories explaining latitudinal gradients in life history strategies. Life history theory predicts higher adult survival in tropical than north temperate regions given lower fecundity and parental effort. Early studies were consistent with this prediction, but standard-effort netting studies in recent decades suggested that apparent survival rates in temperate and tropical regions strongly overlap. Such results do not fit with life history theory. Targeted marking and resighting of breeding adults yielded higher survival estimates in the tropics, but this approach is thought to overestimate survival because it does not sample social and age classes with lower survival. We compared the effect of field methods on tropical survival estimates and their relationships with life history traits.LocationSabah, Malaysian Borneo.Time period2008–2016.Major taxonPasseriformes.MethodsWe used standard-effort netting and resighted individuals of all social and age classes of 18 tropical songbird species over 8 years. We compared apparent survival estimates between these two field methods with differing analytical approaches.ResultsEstimated detection and apparent survival probabilities from standard-effort netting were similar to those from other tropical studies that used standard-effort netting. Resighting data verified that a high proportion of individuals that were never recaptured in standard-effort netting remained in the study area, and many were observed breeding. Across all analytical approaches, addition of resighting yielded substantially higher survival estimates than did standard-effort netting alone. These apparent survival estimates were higher than for temperate zone species, consistent with latitudinal differences in life histories. Moreover, apparent survival estimates from addition of resighting, but not from standard-effort netting alone, were correlated with parental effort as measured by egg temperature across species

Sociodemographic disparities in survival for adolescents and young adults with cancer differ by health insurance status.

PubMed

DeRouen, Mindy C; Parsons, Helen M; Kent, Erin E; Pollock, Brad H; Keegan, Theresa H M

2017-08-01

To investigate associations of sociodemographic factors-race/ethnicity, neighborhood socioeconomic status (SES), and health insurance-with survival for adolescents and young adults (AYAs) with invasive cancer. Data on 80,855 AYAs with invasive cancer diagnosed in California 2001-2011 were obtained from the California Cancer Registry. We used multivariable Cox proportional hazards regression to estimate overall survival. Associations of public or no insurance with greater risk of death were observed for 11 of 12 AYA cancers examined. Compared to Whites, Blacks experienced greater risk of death, regardless of age or insurance, while greater risk of death among Hispanics and Asians was more apparent for younger AYAs and for those with private/military insurance. More pronounced neighborhood SES disparities in survival were observed among AYAs with private/military insurance, especially among younger AYAs. Lacking or having public insurance was consistently associated with shorter survival, while disparities according to race/ethnicity and neighborhood SES were greater among AYAs with private/military insurance. While health insurance coverage associates with survival, remaining racial/ethnic and socioeconomic disparities among AYAs with cancer suggest additional social factors also need consideration in intervention and policy development.

Reduced intensity conditioned allograft yields favorable survival for older adults with B-cell acute lymphoblastic leukemia.

PubMed

Rosko, Ashley; Wang, Hai-Lin; de Lima, Marcos; Sandmaier, Brenda; Khoury, H Jean; Artz, Andrew; Brammer, Johnathan; Bredeson, Christopher; Farag, Sherif; Kharfan-Dabaja, Mohamed; Lazarus, Hillard M; Marks, David I; Bufarull, Rodrigo Martino; McGuirk, Joseph; Mohty, Mohamed; Nishihori, Taiga; Nivison-Smith, Ian; Rashidi, Armin; Ringden, Olle; Seftel, Matthew; Weisdorf, Daniel; Bachanova, Veronika; Saber, Wael

2017-01-01

Older adults with B-cell acute lymphoblastic leukemia (B-ALL) have poor survival. We examined the effectiveness of reduced intensity conditioning (RIC) hematopoietic cell transplant (HCT) in adults with B-ALL age 55 years and older and explored prognostic factors associated with long-term outcomes. Using CIBMTR registry data, we evaluated 273 patients (median age 61, range 55-72) with B-ALL with disease status in CR1 (71%), >CR2 (17%) and Primary Induction Failure (PIF)/Relapse (11%), who underwent RIC HCT between 2001 and 2012 using mostly unrelated donor (59%) or HLA-matched sibling (32%). Among patients with available cytogenetic data, the Philadelphia chromosome (Ph+) was present in 50%. The 3-year cumulative incidences of nonrelapse mortality (NRM) and relapse were 25% (95% confidence intervals (CI): 20-31%) and 47% (95% CI: 41-53%), respectively. Three-year overall survival (OS) was 38% (95% CI: 33-44%). Relapse remained the leading cause of death accounting for 49% of all deaths. In univariate analysis, 3 year risk of NRM was significantly higher with reduced Karnofsky performance status (KPS <90: 34% (95% CI: 25-43%) versus KPS ≥90 (18%; 95% CI: 12-24%, P = 0.006). Mortality was increased in older adults (66+ vs. 55-60: Relative Risk [RR] 1.51 95% CI: 1.00-2.29, P = 0.05) and those with advanced disease (RR 2.13; 95% CI: 1.36-3.34, P = 0.001). Survival of patients in CR1 yields 45% (95% CI: 38-52%) at 3 years and no relapse occurred after 2 years. We report promising OS and acceptable NRM using RIC HCT in older patients with B-ALL. Disease status in CR1 and good performance status are associated with improved outcomes. Am. J. Hematol. 92:42-49, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Sex-specific early survival drives adult sex ratio bias in snowy plovers and impacts mating system and population growth

PubMed Central

Küpper, Clemens; Miller, Tom E. X.; Cruz-López, Medardo; Maher, Kathryn H.; dos Remedios, Natalie; Stoffel, Martin A.; Hoffman, Joseph I.; Krüger, Oliver; Székely, Tamás

2017-01-01

Adult sex ratio (ASR) is a central concept in population biology and a key factor in sexual selection, but why do most demographic models ignore sex biases? Vital rates often vary between the sexes and across life history, but their relative contributions to ASR variation remain poorly understood—an essential step to evaluate sex ratio theories in the wild and inform conservation. Here, we combine structured two-sex population models with individual-based mark–recapture data from an intensively monitored polygamous population of snowy plovers. We show that a strongly male-biased ASR (0.63) is primarily driven by sex-specific survival of juveniles rather than adults or dependent offspring. This finding provides empirical support for theories of unbiased sex allocation when sex differences in survival arise after the period of parental investment. Importantly, a conventional model ignoring sex biases significantly overestimated population viability. We suggest that sex-specific population models are essential to understand the population dynamics of sexual organisms: reproduction and population growth are most sensitive to perturbations in survival of the limiting sex. Overall, our study suggests that sex-biased early survival may contribute toward mating system evolution and population persistence, with implications for both sexual selection theory and biodiversity conservation. PMID:28634289

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

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.

Differential diagnosis of a probable case of non-adult thalassaemia from 4th century AD Romano-British Colchester, UK.

PubMed

Rohnbogner, Anna

2016-12-01

Our current understanding of immigration and diasporic disease in Roman Britain has been greatly enhanced by the recent identification of thalassaemia in the non-adult skeletal record. The wide phenotypic variation in the clinical expression of β-thalassaemia, however, means that additional cases may go unrecognised. A probable diagnosis for β-thalassaemia intermedia or a mild form of major in a 1.0-1.5year old skeleton from Butt Road, Colchester, dating to the 4th century AD is discussed here. The assessment was undertaken using macroscopic and radiographic analysis. Several conditions were apparent, including trauma and probable β-thalassaemia and active vitamin D deficiency. Diagnosis proved difficult due to the challenges that non-adult thalassaemia poses for identification in the skeletal record, as in the absence of the cranium only 'rib-within-a-rib' is currently considered as pathognomonic of the condition. This case demonstrates the variations in expression of this type of genetic anaemia and adds emphasis to a more widespread presence of this important condition in Roman Britain. Copyright © 2016 Elsevier Inc. All rights reserved.

Differential adult survival at close seabird colonies: The importance of spatial foraging segregation and bycatch risk during the breeding season.

PubMed

Genovart, Meritxell; Bécares, Juan; Igual, José-Manuel; Martínez-Abraín, Alejandro; Escandell, Raul; Sánchez, Antonio; Rodríguez, Beneharo; Arcos, José M; Oro, Daniel

2018-03-01

Marine megafauna, including seabirds, are critically affected by fisheries bycatch. However, bycatch risk may differ on temporal and spatial scales due to the uneven distribution and effort of fleets operating different fishing gear, and to focal species distribution and foraging behavior. Scopoli's shearwater Calonectris diomedea is a long-lived seabird that experiences high bycatch rates in longline fisheries and strong population-level impacts due to this type of anthropogenic mortality. Analyzing a long-term dataset on individual monitoring, we compared adult survival (by means of multi-event capture-recapture models) among three close predator-free Mediterranean colonies of the species. Unexpectedly for a long-lived organism, adult survival varied among colonies. We explored potential causes of this differential survival by (1) measuring egg volume as a proxy of food availability and parental condition; (2) building a specific longline bycatch risk map for the species; and (3) assessing the distribution patterns of breeding birds from the three study colonies via GPS tracking. Egg volume was very similar between colonies over time, suggesting that environmental variability related to habitat foraging suitability was not the main cause of differential survival. On the other hand, differences in foraging movements among individuals from the three colonies expose them to differential mortality risk, which likely influenced the observed differences in adult survival. The overlap of information obtained by the generation of specific bycatch risk maps, the quantification of population demographic parameters, and the foraging spatial analysis should inform managers about differential sensitivity to the anthropogenic impact at mesoscale level and guide decisions depending on the spatial configuration of local populations. The approach would apply and should be considered in any species where foraging distribution is colony-specific and mortality risk varies spatially

Adult out-of-hospital cardiac arrest based on chain of survival in Taoyuan County, northern Taiwan.

PubMed

Kuo, Chan-Wei; See, Lai-Chu; Tu, Hui-Tzu; Chen, Jih-Chang

2014-06-01

Most out-of-hospital cardiac arrest (OHCA) studies have been conducted in developed countries or metropolitan areas, and few in developing countries or rural areas. The aims of this study were to determine the weak links in the chain of survival and to estimate the outcomes of OHCA patients in Taoyuan, a nonmetropolitan area in Taiwan. A retrospective review and analysis of OHCA data was conducted. The three outcomes were whether a return of spontaneous circulation (ROSC) was achieved, whether the patient survived to admission, or whether the patient survived to hospital discharge. From April to December 2008, 1048 OHCA patients were resuscitated, and 712 (67.9%) adult cardiac patients were used in this study. Among these 712 patients, 17.8% achieved ROSC (95% confidence interval [CI] 15.2-20.8%), 16.3% survived to admission (95% CI 13.6-19.0%), and 1.4% survived to discharge (95% CI 0.5-2.3%). Factors significantly associated with the three outcomes were witness status, response time to emergency medical services, and whether the patient had a shockable rhythm. Bystander cardiopulmonary resuscitation (CPR) did not add a notable benefit to the outcomes of OHCA. The survival rate of OHCA patients in nonmetropolitan Taiwan was very low (1.4%). Lower witnessed rate, lower bystander CPR rate, and longer response interval in remote areas are the main causes of inferior survival rate. Copyright © 2014 Elsevier Inc. All rights reserved.

Understanding survival analysis: Kaplan-Meier estimate.

PubMed

Goel, Manish Kumar; Khanna, Pardeep; Kishore, Jugal

2010-10-01

Kaplan-Meier estimate is one of the best options to be used to measure the fraction of subjects living for a certain amount of time after treatment. In clinical trials or community trials, the effect of an intervention is assessed by measuring the number of subjects survived or saved after that intervention over a period of time. The time starting from a defined point to the occurrence of a given event, for example death is called as survival time and the analysis of group data as survival analysis. This can be affected by subjects under study that are uncooperative and refused to be remained in the study or when some of the subjects may not experience the event or death before the end of the study, although they would have experienced or died if observation continued, or we lose touch with them midway in the study. We label these situations as censored observations. The Kaplan-Meier estimate is the simplest way of computing the survival over time in spite of all these difficulties associated with subjects or situations. The survival curve can be created assuming various situations. It involves computing of probabilities of occurrence of event at a certain point of time and multiplying these successive probabilities by any earlier computed probabilities to get the final estimate. This can be calculated for two groups of subjects and also their statistical difference in the survivals. This can be used in Ayurveda research when they are comparing two drugs and looking for survival of subjects.

Survival and population size of a resident bird species are declining as temperature increases.

PubMed

Santisteban, Leonard; Benkman, Craig W; Fetz, Trevor; Smith, Julie W

2012-03-01

1. A large number of migratory bird species appear to be declining as the result of climate change, but whether resident bird species have or will be adversely affected by climate change is less clear. We focus on the South Hills crossbill (Loxia curvirostra complex), which is endemic to about 70 km(2) of Rocky Mountain lodgepole pine (Pinus contorta latifolia) forest in southern Idaho, USA. 2. Our results indicate that the South Hills crossbill has declined by over 60% between 2003 and 2008, and that decreasing adult survival drives this population decline. 3. We evaluated the relative support for multiple hypotheses linking crossbill survival to climate, an ectoparasitic mite (scaly-leg mites Knemidokoptes jamaicensis), and the recent emergence of West Nile virus. Changes in adult apparent survival rate were closely associated with average spring and annual temperatures, and with high temperatures (≥32 °C) during summer, which have increased during the last decade. In contrast, there was little evidence that scaly-leg mites or West Nile virus contributed to recent declines in adult survival. 4. The most probable mechanism causing the decline in adult survival and population size is a decrease in the availability of their primary food resource, seeds in serotinous pine cones. Cone production has declined with increasing annual temperatures, and these cones appear to be prematurely opening owing to increasingly hot summer conditions releasing their seeds and reducing the carrying capacity for crossbills later in the year. 5. In light of regional climate change forecasts, which include an increase in both annual temperature and hot days (>32 °C), and the likely disappearance of lodgepole pine from southern Idaho by the end of this century, additional research is needed to determine how to maintain lodgepole pine forests and their supply of seeds to conserve one of the few bird species endemic to the continental United States. © 2011 The Authors. Journal of

Local survival of Dunlin wintering in California

USGS Publications Warehouse

Warnock, N.; Page, G.W.; Sandercock, B.K.

1997-01-01

We estimated local annual survival of 1,051 individually color-banded Dunlin (Calidris alpina) at Bolinas Lagoon, California from 1979 to 1992. Resighting rates for birds banded as adults varied significantly among years, and resighting rates for first-year birds varied by sex and year. No significant differences in local survival rates were found between males and females in any age classes. First-year birds had lower local survival rates than adults. We suspect that raptor predation accounted for much of this difference and other variation in survival rates. Adult Dunlin had lower local survival rates in the year of capture than in subsequent years. Variation in resighting of some groups of individuals including transient Dunlin may account for some differences. However, capture and release of Dunlin may induce short-term behavioral changes that increase the risk of depredation by avian predators within the first few days after capture.

Movement Disorders in Adult Surviving Patients with Maple Syrup Urine Disease

PubMed Central

Carecchio, Miryam; Schneider, Susanne A.; Chan, Heidi; Lachmann, Robin; Lee, Philip J.; Murphy, Elaine; Bhatia, Kailash P.

2014-01-01

Maple syrup urine disease is a rare metabolic disorder caused by mutations in the branched-chain α-keto acid dehydrogenase complex gene. Patients generally present early in life with a toxic encephalopathy because of the accumulation of the branched-chain amino acids leucine, isoleucine, and valine and the corresponding ketoacids. Movement disorders in maple syrup urine disease have typically been described during decompensation episodes or at presentation in the context of a toxic encephalopathy, with complete resolution after appropriate dietary treatment. Movement disorders in patients surviving childhood are not well documented. We assessed 17 adult patients with maple syrup urine disease (mean age, 27.5 years) with a special focus on movement disorders. Twelve (70.6%) had a movement disorder on clinical examination, mainly tremor and dystonia or a combination of both. Parkinsonism and simple motor tics were also observed. Pyramidal signs were present in 11 patients (64.7%), and a spastic-dystonic gait was observed in 6 patients (35.2%). In summary, movement disorders are common in treated adult patients with maple syrup urine disease, and careful neurological examination is advisable to identify those who may benefit from specific therapy. PMID:21484869

Effects of sublethal exposure to boric acid sugar bait on adult survival, host-seeking, bloodfeeding behavior, and reproduction of Stegomyia albopicta.

PubMed

Ali, Arshad; Xue, Rui-De; Barnard, Donald R

2006-09-01

Effects of sublethal exposure to 0.1% boric acid sugar bait on adult survival, host-seeking, bloodfeeding behavior, and reproduction of Stegomyia albopicta were studied in the laboratory. Survival of males as well as females was significantly reduced when exposed to the bait, compared to control adults. The host-seeking and bloodfeeding activities in the baited females decreased, but the mean duration of blood engorgement (probing to voluntary withdrawal of proboscis) was not significantly different between the baited and control females. The landing and biting rates (human forearm) were significantly reduced in the baited females compared to nonbaited controls. Fecundity and fertility (based on number of laid eggs per female and percentage egg hatch, respectively) in the baited females were significantly reduced, and ovarian development was retarded. Sublethal exposure to sugar-based boric acid bait has the potential to reduce adult populations of St. albopicta.

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

The effects of healthy aging on the mnemonic benefit of survival processing

PubMed Central

Stillman, Chelsea M.; Coane, Jennifer H.; Profaci, Caterina P.; Howard, James H.; Howard, Darlene V.

2013-01-01

A number of studies have shown that information is remembered better when it is processed for its survival relevance compared to when it is processed for relevance to other, non-survival-related contexts. Here we conducted three experiments to investigate whether the survival advantage also occurs for healthy older adults. In Experiment 1, older and younger adults rated words for their relevance to a grassland survival or moving scenario and then completed an unexpected free recall test on the words. We replicated the survival advantage in two separate groups of younger adults, one of which was placed under divided-attention conditions, but we did not find a survival advantage in the older adults. We then tested two additional samples of older adults using a between- (Experiment 2) or within-subjects (Experiment 3) design, but still found no evidence of the survival advantage in this age group. These results suggest that, although survival processing is an effective encoding strategy for younger adults, it does not provide the same mnemonic benefit to healthy elders. PMID:23896730

Survival and selection of migrating salmon from capture-recapture models with individual traits

USGS Publications Warehouse

Zabel, R.W.; Wagner, T.; Congleton, J.L.; Smith, S.G.; Williams, J.G.

2005-01-01

Capture-recapture studies are powerful tools for studying animal population dynamics, providing information on population abundance, survival rates, population growth rates, and selection for phenotypic traits. In these studies, the probability of observing a tagged individual reflects both the probability of the individual surviving to the time of recapture and the probability of recapturing an animal, given that it is alive. If both of these probabilities are related to the same phenotypic trait, it can be difficult to distinguish effects on survival probabilities from effects on recapture probabilities. However, when animals are individually tagged and have multiple opportunities for recapture, we can properly partition observed trait-related variability into survival and recapture components. We present an overview of capture-recapture models that incorporate individual variability and develop methods to incorporate results from these models into estimates of population survival and selection for phenotypic traits. We conducted a series of simulations to understand the performance of these estimators and to assess the consequences of ignoring individual variability when it exists. In addition, we analyzed a large data set of > 153 000 juvenile chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) of known length that were PIT-tagged during their seaward migration. Both our simulations and the case study indicated that the ability to precisely estimate selection for phenotypic traits was greatly compromised when differential recapture probabilities were ignored. Estimates of population survival, however, were far more robust. In the chinook salmon and steelhead study, we consistently found that smaller fish had a greater probability of recapture. We also uncovered length-related survival relationships in over half of the release group/river segment combinations that we observed, but we found both positive and negative relationships between length

Familiarity with breeding habitat improves daily survival in colonial cliff swallows

PubMed Central

BROWN, CHARLES R.; BROWN, MARY BOMBERGER; BRAZEAL, KATHLEEN R.

2008-01-01

One probable cost of dispersing to a new breeding habitat is unfamiliarity with local conditions such as the whereabouts of food or the habits of local predators, and consequently immigrants may have lower probabilities of survival than more experienced residents. Within a breeding season, estimated daily survival probabilities of cliff swallows (Petrochelidon pyrrhonota) at colonies in southwestern Nebraska were highest for birds that had always nested at the same site, followed by those for birds that had nested there in some (but not all) past years. Daily survival probabilities were lowest for birds that were naïve immigrants to a colony site and for yearling birds that were nesting for the first time. Birds with past experience at a colony site had monthly survival 8.6% greater than that of naïve immigrants. All colonies where experienced residents did better than immigrants were smaller than 750 nests in size, and in colonies greater than 750 nests, naïve immigrants paid no survival costs relative to experienced residents. Removal of nest ectoparasites by fumigation resulted in higher survival probabilities for all birds, on average, and diminished the differences between immigrants and past residents, probably by improving bird condition to the extent that effects of past experience were relatively less important and harder to detect. The greater survival of experienced residents could not be explained by condition or territory quality, suggesting that familiarity with a local area confers survival advantages during the breeding season for cliff swallows. Colonial nesting may help to moderate the cost of unfamiliarity with an area, likely through social transfer of information about food sources and enhanced vigilance in large groups. PMID:19802326

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.

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.

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

PubMed

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

2016-02-01

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. 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. 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. 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. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Effects of desiccation stress on adult female longevity in Aedes aegypti and Ae. albopictus (Diptera: Culicidae): results of a systematic review and pooled survival analysis.

PubMed

Schmidt, Chris A; Comeau, Genevieve; Monaghan, Andrew J; Williamson, Daniel J; Ernst, Kacey C

2018-04-25

Transmission dynamics of mosquito-borne viruses such as dengue, Zika and chikungunya are affected by the longevity of the adult female mosquito. Environmental conditions influence the survival of adult female Aedes mosquitoes, the primary vectors of these viruses. While the association of temperature with Aedes mortality has been relatively well-explored, the role of humidity is less established. The current study's goals were to compile knowledge of the influence of humidity on adult survival in the important vector species Aedes aegypti and Ae. albopictus, and to quantify this relationship while accounting for the modifying effect of temperature. We performed a systematic literature review to identify studies reporting experimental results informing the relationships among temperature, humidity and adult survival in Ae. aegypti and Ae. albopictus. Using a novel simulation approach to harmonize disparate survival data, we conducted pooled survival analyses via stratified and mixed effects Cox regression to estimate temperature-dependent associations between humidity and mortality risk for these species across a broad range of temperatures and vapor pressure deficits. After screening 1517 articles, 17 studies (one in semi-field and 16 in laboratory settings) met inclusion criteria and collectively reported results for 192 survival experiments. We review and synthesize relevant findings from these studies. Our stratified model estimated a strong temperature-dependent association of humidity with mortality in both species, though associations were not significant for Ae. albopictus in the mixed effects model. Lowest mortality risks were estimated around 27.5 °C and 21.5 °C for Ae. aegypti and Ae. albopictus, respectively, and mortality increased non-linearly with decreasing humidity. Aedes aegypti had a survival advantage relative to Ae. albopictus in the stratified model under most conditions, but species differences were not significant in the mixed effects model

Volunteering is associated with increased survival in able-bodied participants of the English Longitudinal Study of Ageing

PubMed Central

Rogers, Nina Trivedy; Demakakos, Panayotes; Taylor, Mark Steven; Steptoe, Andrew; Hamer, Mark; Shankar, Aparna

2018-01-01

Background Volunteering has been linked to reduced mortality in older adults but the mechanisms explaining this effect remain unclear. This study investigated whether volunteering is associated with increased survival in participants of the English Longitudinal Study of Ageing and whether differences in survival are modified by functional disabilities. Methods A multivariate Cox Proportional Hazards model was used to estimate the association of volunteering with survival over a period of 10.9 years in 10,324 participants, whilst controlling for selected confounders. To investigate effect modification by disability, the analyses were repeated in participants with and without self-reported functional disabilities. Results Volunteering was associated with a reduced probability of death from all-causes in univariate analyses (HR = 0.65, CI 0.58–0.73, P < 0.0001), but adjustment for covariates rendered this association non-significant (HR = 0.90, CI 0.79–1.01, P = 0.07). Able-bodied volunteers had significantly increased survival compared to able-bodied non-volunteers (HR = 0.81, 95% CI: 0.69 – 0.95, P = 0.009). There was no significant survival advantage among disabled volunteers, compared to disabled non-volunteers (HR = 1.06, CI 0.88–1.29, P = 0.53). Conclusion Volunteering is associated with reduced mortality in older adults in England, but this effect appears to be limited to volunteers who report no disabilities. PMID:26811548

Effects of absolute fasting on reproduction and survival of the invasive apple snail Pomacea canaliculata in its native range.

PubMed

Tamburi, Nicolás E; Martín, Pablo R

2016-08-01

A South American freshwater gastropod, the apple snail Pomacea canaliculata, has become a driver of ecosystemic changes in wetlands and an important rice pest after its introduction to various parts of the world, mainly Asia. The objective of this study was to study the effect of an abrupt interruption in food availability in the short term (up to 4 weeks) and long term (up to 8 months) on survival and reproductive activity. The main results indicate that short-term fasting mainly affects the survival of males, but only when they are raised together with females, probably due to a greater mate-searching activity that increases mortality in the individuals with lower reserves. The number of copulating snails or egg-laying females shows an abrupt drop when fasting and a rapid recovery after the food supply is restored. The strategy of discontinuing reproductive activity prioritizes energy conservation for the survival of the females. Interpopulation variation in resistance to starvation was observed in adults, which can be explained to some extent by the food availability that they experienced in their natural environment. No interpopulational differences in survival were seen in hatchlings. The mean maximum values of survival under starvation were 52.6 days in hatchlings and the 3.3% of adults survive over than 200 days, which may be a relevant trait in dispersal and establishment in new habitats.

Survival among children and adults with sickle cell disease in Belgium: Benefit from hydroxyurea treatment.

PubMed

Lê, Phu Quoc; Gulbis, Béatrice; Dedeken, Laurence; Dupont, Sophie; Vanderfaeillie, Anna; Heijmans, Catherine; Huybrechts, Sophie; Devalck, Christine; Efira, André; Dresse, Marie-Françoise; Rozen, Laurence; Benghiat, Fleur Samantha; Ferster, Alina

2015-11-01

To evaluate the survival of patients with sickle cell disease (SCD) recorded in the Belgian SCD Registry and to assess the impact of disease-modifying treatments (DMT). The Registry created in 2008 included patients of eight centers. All available data in 2008 were retrospectively encoded in the database. After 2008 and until 2012, all data were recorded prospectively for already registered patients as well as newly diagnosed subjects. Data were registered from neonatal screening or from diagnosis (first contact) until last follow-up or death. Data included diagnosis, demography, and outcome data. We collected data from 469 patients over a 5,110 patient years (PY) follow-up period. The global mortality rate was low (0.25/100 PY), although 13 patients died (2.8%) and was similar between children, adolescents (10-18 years), and young adults (P = 0.76). Out of the cohort, 185 patients received hydroxyurea at last follow-up (median duration of treatment: 10.3 years), 90 underwent hematopoietic stem cell transplantation (HSCT), 24 were chronically transfused, and 170 had never had any DMT. Hydroxyurea showed significant benefit on patients outcome as reflected by a lower mortality rate compared to transplanted individuals or people without DMT (0.14, 0.36, and 0.38 per 100 PY, respectively) and by higher Kaplan-Meier estimates of 15 year survival (99.4%) compared to HSCT (93.8%; P = 0.01) or no DMT groups (95.4%; P = 0.04). SCD mortality in Belgium is low with no increase observed in young adults. Patients treated with hydroxyurea demonstrate a significant benefit in survival when compared to those without DMT or transplanted. © 2015 Wiley Periodicals, Inc.

Modeling the effect of toe clipping on treefrog survival: Beyond the return rate

USGS Publications Warehouse

Waddle, J.H.; Rice, K.G.; Mazzotti, F.J.; Percival, H.F.

2008-01-01

Some studies have described a negative effect of toe clipping on return rates of marked anurans, but the return rate is limited in that it does not account for heterogeneity of capture probabilities. We used open population mark-recapture models to estimate both apparent survival (ϕ) and the recapture probability (p) of two treefrog species individually marked by clipping 2–4 toes. We used information-theoretic model selection to examine the effect of toe clipping on survival while accounting for variation in capture probability. The model selection results indicate strong support for an effect of toe clipping on survival of Green Treefrogs (Hyla cinerea) and only limited support for an effect of toe clipping on capture probability. We estimate there was a mean absolute decrease in survival of 5.02% and 11.16% for Green Treefrogs with three and four toes removed, respectively, compared to individuals with just two toes removed. Results for Squirrel Treefrogs (Hyla squirella) indicate little support for an effect of toe clipping on survival but may indicate some support for a negative effect on capture probability. We believe that the return rate alone should not be used to examine survival of marked animals because constant capture probability must be assumed, and our examples demonstrate how capture probability may vary over time and among groups. Mark-recapture models provide a method for estimating the effect of toe clipping on anuran survival in situations where unique marks are applied.

Survival of breeding Pacific common eiders on the Yukon-Kuskokwim Delta, Alaska

USGS Publications Warehouse

Wilson, H.M.; Flint, Paul L.; Moran, Christine L.; Powell, A.N.

2007-01-01

Populations of Pacific common eiders (Somateria mollissima v-nigrum) breeding in Alaska, USA, have declined markedly over the past 40 years. We studied survival of adult female Pacific common eiders using capture—recapture of nesting hens at 3 sites on the Yukon-Kuskokwim Delta (YKD), Alaska from 1994 to 2004. We used data consisting of 268 recapture events from 361 uniquely marked individuals to investigate temporal, geographic, and environmental variation in adult female survival. Our results suggest apparent annual survival of adult eiders from the YKD was high (0.892, SE = 0.022) and spatially and temporally invariant (σ2 = 0.005), a pattern consistent with other long-lived marine birds. Moreover, our results suggest adult survival may be functionally fixed for Pacific common eiders, and at the present, adult survival may be relatively unresponsive to environmental or management perturbations. Our data did not support hypothesized variation in survival relative to mortality factors such as predation on breeding grounds, physiologic costs of reproduction, and wintering conditions. Although changes in adult survival likely have a large potential effect on prospective population growth, our results suggest viable management actions aimed at increasing survival may be extremely limited.

Larval and adult environmental temperatures influence the adult reproductive traits of Anopheles gambiae s.s.

PubMed

Christiansen-Jucht, Céline D; Parham, Paul E; Saddler, Adam; Koella, Jacob C; Basáñez, María-Gloria

2015-09-17

Anopheles mosquito life-history parameters and population dynamics strongly influence malaria transmission, and environmental factors, particularly temperature, strongly affect these parameters. There are currently some studies on how temperature affects Anopheles gambiae s.s. survival but very few exist examining other life-history traits. We investigate here the effect of temperature on population dynamics parameters. Anopheles gambiae s.s. immatures were reared individually at 23 ± 1 °C, 27 ± 1 °C, 31 ± 1 °C, and 35 ± 1 °C, and adults were held at their larval temperature or at one of the other temperatures. Larvae were checked every 24 h for development to the next stage and measured for size; wing length was measured as a proxy for adult size. Females were blood fed three times, and the number of females feeding and laying eggs was counted. The numbers of eggs and percentage of eggs hatched were recorded. Increasing temperatures during the larval stages resulted in significantly smaller larvae (p = 0.005) and smaller adults (p < 0.001). Adult temperature had no effect on the time to egg laying, and the larval temperature of adults only affected the incubation period of the first egg batch. Temperature influenced the time to hatching of eggs, as well as the time to development at every stage. The number of eggs laid was highest when adults were kept at 27 °C, and lowest at 31 °C, and higher adult temperatures decreased the proportion of eggs hatching after the second and third blood meal. Higher adult temperatures significantly decreased the probability of blood feeding, but the larval temperature of adults had no influence on the probability of taking a blood meal. Differences were observed between the first, second, and third blood meal in the times to egg laying and hatching, number of eggs laid, and probabilities of feeding and laying eggs. Our study shows that environmental temperature during the larval stages as

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…

Survival and recovery rates of American woodcock banded in Michigan

USGS Publications Warehouse

Krementz, David G.; Hines, James E.; Luukkonen, David R.

2003-01-01

American woodcock (Scolopax minor) population indices have declined since U.S. Fish and Wildlife Service (USFWS) monitoring began in 1968. Management to stop and/or reverse this population trend has been hampered by the lack of recent information on woodcock population parameters. Without recent information on survival rate trends, managers have had to assume that the recent declines in recruitment indices are the only parameter driving woodcock declines. Using program MARK, we estimated annual survival and recovery rates of adult and juvenile American woodcock, and estimated summer survival of local (young incapable of sustained flight) woodcock banded in Michigan between 1978 and 1998. We constructed a set of candidate models from a global model with age (local, juvenile, adult) and time (year)-dependent survival and recovery rates to no age or time-dependent survival and recovery rates. Five models were supported by the data, with all models suggesting that survival rates differed among age classes, and 4 models had survival rates that were constant over time. The fifth model suggested that juvenile and adult survival rates were linear on a logit scale over time. Survival rates averaged over likelihood-weighted model results were 0.8784 +/- 0.1048 (SE) for locals, 0.2646 +/- 0.0423 (SE) for juveniles, and 0.4898 +/- 0.0329 (SE) for adults. Weighted average recovery rates were 0.0326 +/- 0.0053 (SE) for juveniles and 0.0313 +/- 0.0047 (SE) for adults. Estimated differences between our survival estimates and those from prior years were small, and our confidence around those differences was variable and uncertain. juvenile survival rates were low.

Tissue Mercury Concentrations and Survival of Tree Swallow Embryos, Nestlings and Young Adult Females on a Contaminated Site.

PubMed

Taylor, Capwell E; Cristol, Daniel A

2015-10-01

Tree swallows nesting on mercury-contaminated sites along the South River in Virginia, USA were monitored for reproductive success. The bodies of nestlings found deceased in their nest boxes were collected, along with blood and feather samples from the adult parents and surviving siblings. We also measured hatching and fledging success of the clutches and the annual recapture rate of adults. We found that the body feathers of deceased nestlings contained significantly higher concentrations of mercury (12.89 ± 8.42 μg/g, n = 15) than those of nestlings that survived to fledge (7.41 ± 4.79 μg/g, n = 15). However, mothers of more successful clutches (>75 % hatching) did not differ in mercury concentrations from females with less successful clutches (<50 % hatching). Additionally, adult females breeding for the first time that returned to breed the following year did not differ in blood mercury from females of the same age that bred once but never returned. Our results suggest that mercury had its greatest effect on these songbirds during the nestling stage, whereas for embryos or first-time breeding females, other factors likely played larger roles in mortality.

Enhanced secondary analysis of survival data: reconstructing the data from published Kaplan-Meier survival curves.

PubMed

Guyot, Patricia; Ades, A E; Ouwens, Mario J N M; Welton, Nicky J

2012-02-01

The results of Randomized Controlled Trials (RCTs) on time-to-event outcomes that are usually reported are median time to events and Cox Hazard Ratio. These do not constitute the sufficient statistics required for meta-analysis or cost-effectiveness analysis, and their use in secondary analyses requires strong assumptions that may not have been adequately tested. In order to enhance the quality of secondary data analyses, we propose a method which derives from the published Kaplan Meier survival curves a close approximation to the original individual patient time-to-event data from which they were generated. We develop an algorithm that maps from digitised curves back to KM data by finding numerical solutions to the inverted KM equations, using where available information on number of events and numbers at risk. The reproducibility and accuracy of survival probabilities, median survival times and hazard ratios based on reconstructed KM data was assessed by comparing published statistics (survival probabilities, medians and hazard ratios) with statistics based on repeated reconstructions by multiple observers. The validation exercise established there was no material systematic error and that there was a high degree of reproducibility for all statistics. Accuracy was excellent for survival probabilities and medians, for hazard ratios reasonable accuracy can only be obtained if at least numbers at risk or total number of events are reported. The algorithm is a reliable tool for meta-analysis and cost-effectiveness analyses of RCTs reporting time-to-event data. It is recommended that all RCTs should report information on numbers at risk and total number of events alongside KM curves.

Survival and reproduction of radio-marked adult spotted owls.

Treesearch

C.C. Foster; E.D. Forsman; E.C. Meslow; G.S. Miller; J.A. Reid; F.F. Wagner; A.B. Carey; J.B. Lint

1992-01-01

We compared survival, reproduction, and body mass of radio-marked and non radio-marked spotted owls (Strix occidentalis) to determine if backpack radios influenced reproduction or survival. In most study areas and years, there were no differences (P > 0.05) in survival of males and females or in survival of radio-marked versus banded owls. There...

Movement disorders in adult surviving patients with maple syrup urine disease.

PubMed

Carecchio, Miryam; Schneider, Susanne A; Chan, Heidi; Lachmann, Robin; Lee, Philip J; Murphy, Elaine; Bhatia, Kailash P

2011-06-01

Maple syrup urine disease is a rare metabolic disorder caused by mutations in the branched-chain α-keto acid dehydrogenase complex gene. Patients generally present early in life with a toxic encephalopathy because of the accumulation of the branched-chain amino acids leucine, isoleucine, and valine and the corresponding ketoacids. Movement disorders in maple syrup urine disease have typically been described during decompensation episodes or at presentation in the context of a toxic encephalopathy, with complete resolution after appropriate dietary treatment. Movement disorders in patients surviving childhood are not well documented. We assessed 17 adult patients with maple syrup urine disease (mean age, 27.5 years) with a special focus on movement disorders. Twelve (70.6%) had a movement disorder on clinical examination, mainly tremor and dystonia or a combination of both. Parkinsonism and simple motor tics were also observed. Pyramidal signs were present in 11 patients (64.7%), and a spastic-dystonic gait was observed in 6 patients (35.2%). In summary, movement disorders are common in treated adult patients with maple syrup urine disease, and careful neurological examination is advisable to identify those who may benefit from specific therapy. © 2011 Movement Disorder Society. Copyright © 2011 Movement Disorder Society.

Survival of cackling Canada geese, 1982-1988

USGS Publications Warehouse

Raveling, D.G.; Nichols, J.D.; Hines, J.E.; Zezulak, D.S.; Silveira, J.G.; Johnson, J.C.; Aldrich, T.W.; Weldon, J.A.

1992-01-01

We estimated seasonal and annual survival rates of cackling Canada geese (Branta canadensis minima ) for the period 1982-1989 to identify periods of high mortality and assess effects of harvest management decisions. We tested hypotheses about age- and sex-specific variation in survival, seasonal variation in survival rates, and variation in survival between years in which hunting seasons were open and closed. Geese were marked with individually identifiable neckbands and observed from autumn through spring. We used these data to estimate survival rates for 3-month periods in early (EW) and late (LW) winter and a 6-month period in summer (SU). Mean annual survival rates of immature females were lower than those of adults over the entire study. Survival rates of immature males were lower than those of adults during the 2 years with sport hunting seasons. We found no evidence of sex-specific differences in seasonal or annual survival rates of immature geese.

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.

The effects of body mass index on graft survival in adult recipients transplanted with single pediatric kidneys.

PubMed

Balamuthusamy, Saravanan; Paramesh, Anil; Zhang, Rubin; Florman, Sander; Shenava, Rajesh; Islam, Tareq; Wagner, Janis; Killackey, Mary; Alper, Brent; Simon, Eric E; Slakey, Douglas

2009-01-01

There is insufficient data on the impact of recipient body mass index (BMI) on the long-term graft survival of adult patients transplanted with single pediatric kidneys. We performed a retrospective analysis of adult patients transplanted with single pediatric kidneys at our center. The recipients were classified into 2 groups: group 1 (BMI > or =30) and group 2 (BMI <30). Donor/recipient demographics, postoperative outcomes and survival rates were compared between the 2 groups. There was no significant difference in donor/recipient demographics between the 2 groups. In group 1, the death-censored graft survival (DCGS) at 1, 3 and 5 years was 90% at all 3 time points, and in group 2 it was 86, 68 and 60%, respectively (p = 0.05). The mean glomerular filtration rate (with standard deviation in parentheses) at 1, 3 and 5 years was, respectively, 55 (15), 59 (19) and 55 (28) ml/min for group 1, compared to 65 (28), 69 (23) and 67 (20) ml/min in group 2 (p = NS). Multivariate analysis revealed a hazard ratio of 5.12 (95% confidence interval 1.06-24.7; p = 0.04) for graft loss in nonobese patients when compared to obese patients. Obese patients had an increased risk for acute rejections within the first month of transplant (p = 0.02). Patients with a BMI > or =30 transplanted with single pediatric kidneys have better DCGS rates when compared to nonobese patients. Copyright (c) 2008 S. Karger AG, Basel.

Comparison of dynamic treatment regimes via inverse probability weighting.

PubMed

Hernán, Miguel A; Lanoy, Emilie; Costagliola, Dominique; Robins, James M

2006-03-01

Appropriate analysis of observational data is our best chance to obtain answers to many questions that involve dynamic treatment regimes. This paper describes a simple method to compare dynamic treatment regimes by artificially censoring subjects and then using inverse probability weighting (IPW) to adjust for any selection bias introduced by the artificial censoring. The basic strategy can be summarized in four steps: 1) define two regimes of interest, 2) artificially censor individuals when they stop following one of the regimes of interest, 3) estimate inverse probability weights to adjust for the potential selection bias introduced by censoring in the previous step, 4) compare the survival of the uncensored individuals under each regime of interest by fitting an inverse probability weighted Cox proportional hazards model with the dichotomous regime indicator and the baseline confounders as covariates. In the absence of model misspecification, the method is valid provided data are available on all time-varying and baseline joint predictors of survival and regime discontinuation. We present an application of the method to compare the AIDS-free survival under two dynamic treatment regimes in a large prospective study of HIV-infected patients. The paper concludes by discussing the relative advantages and disadvantages of censoring/IPW versus g-estimation of nested structural models to compare dynamic regimes.

Estimating the probability of survival of individual shortleaf pine (Pinus echinata mill.) trees

Treesearch

Sudip Shrestha; Thomas B. Lynch; Difei Zhang; James M. Guldin

2012-01-01

A survival model is needed in a forest growth system which predicts the survival of trees on individual basis or on a stand basis (Gertner, 1989). An individual-tree modeling approach is one of the better methods available for predicting growth and yield as it provides essential information about particular tree species; tree size, tree quality and tree present status...

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.

WE-H-BRA-08: A Monte Carlo Cell Nucleus Model for Assessing Cell Survival Probability Based On Particle Track Structure Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, B; Georgia Institute of Technology, Atlanta, GA; Wang, C

Purpose: To correlate the damage produced by particles of different types and qualities to cell survival on the basis of nanodosimetric analysis and advanced DNA structures in the cell nucleus. Methods: A Monte Carlo code was developed to simulate subnuclear DNA chromatin fibers (CFs) of 30nm utilizing a mean-free-path approach common to radiation transport. The cell nucleus was modeled as a spherical region containing 6000 chromatin-dense domains (CDs) of 400nm diameter, with additional CFs modeled in a sparser interchromatin region. The Geant4-DNA code was utilized to produce a particle track database representing various particles at different energies and dose quantities.more » These tracks were used to stochastically position the DNA structures based on their mean free path to interaction with CFs. Excitation and ionization events intersecting CFs were analyzed using the DBSCAN clustering algorithm for assessment of the likelihood of producing DSBs. Simulated DSBs were then assessed based on their proximity to one another for a probability of inducing cell death. Results: Variations in energy deposition to chromatin fibers match expectations based on differences in particle track structure. The quality of damage to CFs based on different particle types indicate more severe damage by high-LET radiation than low-LET radiation of identical particles. In addition, the model indicates more severe damage by protons than of alpha particles of same LET, which is consistent with differences in their track structure. Cell survival curves have been produced showing the L-Q behavior of sparsely ionizing radiation. Conclusion: Initial results indicate the feasibility of producing cell survival curves based on the Monte Carlo cell nucleus method. Accurate correlation between simulated DNA damage to cell survival on the basis of nanodosimetric analysis can provide insight into the biological responses to various radiation types. Current efforts are directed at producing

A case of low success of blind vaccination campaigns against myxomatosis and rabbit haemorrhagic disease on survival of adult European wild rabbits.

PubMed

Rouco, Carlos; Moreno, Sacramento; Santoro, Simone

2016-10-01

Vaccination campaigns against myxomatosis and rabbit haemorrhagic disease (RHD) are commonly used in translocation programs conducted for the purpose of recovering wild European rabbit populations in Iberian Mediterranean ecosystems. In most cases rabbits are vaccinated 'blind' (i.e. without assessing their prior immunological status) for economic and logistic reasons. However, there is conflicting evidence on the effectiveness of such an approach. We tested whether blind vaccination against myxomatosis and rabbit haemorrhagic disease improved rabbit survival in a rabbit translocation program where wild rabbits were kept in semi-natural conditions in three enclosures. We conducted nine capture sessions over two years (2008-2010) and used the information collected to compare the survival of vaccinated (n=511) versus unvaccinated (n=161) adult wild rabbits using capture-mark-recapture analysis. Average monthly survival was no different for vaccinated versus unvaccinated individuals, both in the period between release and first capture (short-term) and after the first capture onward (long-term). Rabbit survival was lower in the short term than in the long term regardless of whether rabbits were vaccinated or not. Lower survival in the short-term could be due to the stress induced by the translocation process itself (e.g. handling stress). However, we did not find any overall effect of vaccination on survival which could be explained by two non-exclusive reasons. First, interference of the vaccine with the natural antibodies in the donor population. Due to donor populations have high density of rabbits with, likely, high prevalence of antibodies as a result of previous natural exposure to these diseases. Second, the lack of severe outbreaks during the study period. Based on our findings we argue that blind vaccination of adult rabbits in translocation programs may be often mostly ineffective and unnecessarily costly. In particular, since outbreaks are hard to predict

Fitness Consequences of Boldness in Juvenile and Adult Largemouth Bass.

PubMed

Ballew, Nicholas G; Mittelbach, Gary G; Scribner, Kim T

2017-04-01

To date, most studies investigating the relationship between personality traits and fitness have focused on a single measure of fitness (such as survival) at a specific life stage. However, many personality traits likely have multiple effects on fitness, potentially operating across different functional contexts and stages of development. Here, we address the fitness consequences of boldness, under seminatural conditions, across life stages and functional contexts in largemouth bass (Micropterus salmoides). Specifically, we report the effect of boldness on (1) juvenile survivorship in an outdoor pond containing natural prey and predators and (2) adult reproductive success in three outdoor ponds across three reproductive seasons (years). Juvenile survival was negatively affected by boldness, with bolder juveniles having a lower probability of survival than shyer juveniles. In contrast, bolder adult male bass had greater reproductive success than their shyer male counterparts. Female reproductive success was not affected by boldness. These findings demonstrate that boldness can affect fitness differently across life stages. Further, boldness was highly consistent across years and significantly heritable, which suggests that boldness has a genetic component. Thus, our results support theory suggesting that fitness trade-offs across life stages may contribute to the maintenance of personality variation within populations.

The effect of delayed graft function on graft and patient survival in kidney transplantation: an approach using competing events analysis.

PubMed

Fonseca, Isabel; Teixeira, Laetitia; Malheiro, Jorge; Martins, La Salete; Dias, Leonídio; Castro Henriques, António; Mendonça, Denisa

2015-06-01

In kidney transplantation, the impact of delayed graft function (DGF) on long-term graft and patient survival is controversial. We examined the impact of DGF on graft and recipient survival by accounting for the possibility that death with graft function may act as a competing risk for allograft failure. We used data from 1281 adult primary deceased-donor kidney recipients whose allografts functioned at least 1 year. The probability of graft loss occurrence is overestimated using the complement of Kaplan-Meier estimates (1-KM). Both the cause-specific Cox proportional hazard regression model (standard Cox) and the subdistribution hazard regression model proposed by Fine and Gray showed that DGF was associated with shorter time to graft failure (csHR = 2.0, P = 0.002; sHR = 1.57, P = 0.009), independent of acute rejection (AR) and after adjusting for traditional factors associated with graft failure. Regarding patient survival, DGF was a predictor of patient death using the cause-specific Cox model (csHR = 1.57, P = 0.029) but not using the subdistribution model. The probability of graft loss from competing end points should not be reported with the 1-KM. Application of a regression model for subdistribution hazard showed that, independent of AR, DGF has a detrimental effect on long-term graft survival, but not on patient survival. © 2015 Steunstichting ESOT.

Survival, causes of mortality, and reproduction in American marten in northeastern Oregon.

Treesearch

Evelyn L. Bull; Thad W. Heater

2001-01-01

Survival rates, causes of mortality, and reproduction in the American marten (Martes americana) were determined in northeastern Oregon from 1994 until 1997 with radiocollared martens. The probability of survival of martens ≥9 mo old was 0.55 for 1 yr, 0.37 for 2 yr, 0.22 for 3 yr, and 0.15 for 4 yr. The mean annual probability of survival...

Hospital of Diagnosis Influences the Probability of Receiving Curative Treatment for Esophageal Cancer.

PubMed

van Putten, Margreet; Koëter, Marijn; van Laarhoven, Hanneke W M; Lemmens, Valery E P P; Siersema, Peter D; Hulshof, Maarten C C M; Verhoeven, Rob H A; Nieuwenhuijzen, Grard A P

2018-02-01

The aim of this article was to study the influence of hospital of diagnosis on the probability of receiving curative treatment and its impact on survival among patients with esophageal cancer (EC). Although EC surgery is centralized in the Netherlands, the disease is often diagnosed in hospitals that do not perform this procedure. Patients with potentially curable esophageal or gastroesophageal junction tumors diagnosed between 2005 and 2013 who were potentially curable (cT1-3,X, any N, M0,X) were selected from the Netherlands Cancer Registry. Multilevel logistic regression was performed to examine the probability to undergo curative treatment (resection with or without neoadjuvant treatment, definitive chemoradiotherapy, or local tumor excision) according to hospital of diagnosis. Effects of variation in probability of undergoing curative treatment among these hospitals on survival were investigated by Cox regression. All 13,017 patients with potentially curable EC, diagnosed in 91 hospitals, were included. The proportion of patients receiving curative treatment ranged from 37% to 83% and from 45% to 86% in the periods 2005-2009 and 2010-2013, respectively, depending on hospital of diagnosis. After adjustment for patient- and hospital-related characteristics these proportions ranged from 41% to 77% and from 50% to 82%, respectively (both P < 0.001). Multivariable survival analyses showed that patients diagnosed in hospitals with a low probability of undergoing curative treatment had a worse overall survival (hazard ratio = 1.13, 95% confidence interval 1.06-1.20; hazard ratio = 1.15, 95% confidence interval 1.07-1.24). The variation in probability of undergoing potentially curative treatment for EC between hospitals of diagnosis and its impact on survival indicates that treatment decision making in EC may be improved.

How Life History Can Sway the Fixation Probability of Mutants

PubMed Central

Li, Xiang-Yi; Kurokawa, Shun; Giaimo, Stefano; Traulsen, Arne

2016-01-01

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

Burrowing (Speotyto cunicularia) Owl survival in prairie Canada

Treesearch

Kort M. Clayton; Josef K. Schmutz

1997-01-01

We studied survival of the endangered Burrowing Owl (Speotyto cunicularia) using radio-telemetry in both Alberta and Saskatchewan. Adult females exhibited the highest mean survival (0.83) whereas adult male (0.46) and juvenile (0.48) rates were similar. Most mortality occurred during the post-fledging period when there was a peak of activity around...

Testing assumptions for unbiased estimation of survival of radiomarked harlequin ducks

USGS Publications Warehouse

Esler, Daniel N.; Mulcahy, Daniel M.; Jarvis, Robert L.

2000-01-01

Unbiased estimates of survival based on individuals outfitted with radiotransmitters require meeting the assumptions that radios do not affect survival, and animals for which the radio signal is lost have the same survival probability as those for which fate is known. In most survival studies, researchers have made these assumptions without testing their validity. We tested these assumptions by comparing interannual recapture rates (and, by inference, survival) between radioed and unradioed adult female harlequin ducks (Histrionicus histrionicus), and for radioed females, between right-censored birds (i.e., those for which the radio signal was lost during the telemetry monitoring period) and birds with known fates. We found that recapture rates of birds equipped with implanted radiotransmitters (21.6 ± 3.0%; x̄ ± SE) were similar to unradioed birds (21.7 ± 8.6%), suggesting that radios did not affect survival. Recapture rates also were similar between right-censored (20.6 ± 5.1%) and known-fate individuals (22.1 ± 3.8%), suggesting that missing birds were not subject to differential mortality. We also determined that capture and handling resulted in short-term loss of body mass for both radioed and unradioed females and that this effect was more pronounced for radioed birds (the difference between groups was 15.4 ± 7.1 g). However, no difference existed in body mass after recapture 1 year later. Our study suggests that implanted radios are an unbiased method for estimating survival of harlequin ducks and likely other species under similar circumstances.

Generic dynamical features of quenched interacting quantum systems: Survival probability, density imbalance, and out-of-time-ordered correlator

NASA Astrophysics Data System (ADS)

Torres-Herrera, E. J.; García-García, Antonio M.; Santos, Lea F.

2018-02-01

We study numerically and analytically the quench dynamics of isolated many-body quantum systems. Using full random matrices from the Gaussian orthogonal ensemble, we obtain analytical expressions for the evolution of the survival probability, density imbalance, and out-of-time-ordered correlator. They are compared with numerical results for a one-dimensional-disordered model with two-body interactions and shown to bound the decay rate of this realistic system. Power-law decays are seen at intermediate times, and dips below the infinite time averages (correlation holes) occur at long times for all three quantities when the system exhibits level repulsion. The fact that these features are shared by both the random matrix and the realistic disordered model indicates that they are generic to nonintegrable interacting quantum systems out of equilibrium. Assisted by the random matrix analytical results, we propose expressions that describe extremely well the dynamics of the realistic chaotic system at different time scales.

A new algorithm for finding survival coefficients employed in reliability equations

NASA Technical Reports Server (NTRS)

Bouricius, W. G.; Flehinger, B. J.

1973-01-01

Product reliabilities are predicted from past failure rates and reasonable estimate of future failure rates. Algorithm is used to calculate probability that product will function correctly. Algorithm sums the probabilities of each survival pattern and number of permutations for that pattern, over all possible ways in which product can survive.

Adult-onset deficiency in growth hormone and insulin-like growth factor-I decreases survival of dentate granule neurons: insights into the regulation of adult hippocampal neurogenesis.

PubMed

Lichtenwalner, Robin J; Forbes, M Elizabeth; Sonntag, William E; Riddle, David R

2006-02-01

Insulin-like growth factor-I (IGF-I), long thought to provide critical trophic support during development, also has emerged as a candidate for regulating ongoing neuronal production in adulthood. Whether and how IGF-I influences each phase of neurogenesis, however, remains unclear. In the current study, we used a selective model of growth hormone (GH) and plasma IGF-I deficiency to evaluate the role of GH and IGF-I in regulating cell proliferation, survival, and neuronal differentiation in the adult dentate gyrus. GH/IGF-I-deficient dwarf rats of the Lewis strain were made GH/IGF-I replete throughout development via twice daily injections of GH, and then GH/IGF-I deficiency was initiated in adulthood by removing animals from GH treatment. Bromodeoxyuridine (BrdU) labeling revealed no effect of GH/IGF-I deficiency on cell proliferation, but adult-onset depletion of GH and plasma IGF-I significantly reduced the survival of newly generated cells in the dentate gyrus. Colabeling for BrdU and markers of immature and mature neurons revealed a selective effect of GH/IGF-I deficiency on the survival of more mature new neurons. The number of BrdU-labeled cells expressing the immature neuronal marker TUC-4 did not differ between GH/IGF-I-deficient and -replete animals, but the number expressing only the marker of maturity NeuN was lower in depleted animals. Taken together, results from the present study suggest that, under conditions of short-term GH/IGF-I deficiency during adulthood, dentate granule cells continue to be produced, to commit to a neuronal fate, and to begin the process of neuronal maturation, whereas survival of the new neurons is impaired. Copyright 2005 Wiley-Liss, Inc.

How long do the dead survive on the road? Carcass persistence probability and implications for road-kill monitoring surveys.

PubMed

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

2011-01-01

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. 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. The guidance given here on monitoring frequencies is particularly relevant to provide conservation and transportation agencies with accurate numbers of road

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

Survival analysis of cervical cancer using stratified Cox regression

NASA Astrophysics Data System (ADS)

Purnami, S. W.; Inayati, K. D.; Sari, N. W. Wulan; Chosuvivatwong, V.; Sriplung, H.

2016-04-01

Cervical cancer is one of the mostly widely cancer cause of the women death in the world including Indonesia. Most cervical cancer patients come to the hospital already in an advanced stadium. As a result, the treatment of cervical cancer becomes more difficult and even can increase the death's risk. One of parameter that can be used to assess successfully of treatment is the probability of survival. This study raises the issue of cervical cancer survival patients at Dr. Soetomo Hospital using stratified Cox regression based on six factors such as age, stadium, treatment initiation, companion disease, complication, and anemia. Stratified Cox model is used because there is one independent variable that does not satisfy the proportional hazards assumption that is stadium. The results of the stratified Cox model show that the complication variable is significant factor which influent survival probability of cervical cancer patient. The obtained hazard ratio is 7.35. It means that cervical cancer patient who has complication is at risk of dying 7.35 times greater than patient who did not has complication. While the adjusted survival curves showed that stadium IV had the lowest probability of survival.

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

Improved survival in HIV treatment programs in Asia

PubMed Central

De La Mata, Nicole L; Kumarasamy, Nagalingeswaran; Khol, Vohith; Ng, Oon Tek; Van Nguyen, Kinh; Merati, Tuti Parwati; Pham, Thuy Thanh; Lee, Man Po; Durier, Nicolas; Law, Matthew

2016-01-01

Background Antiretroviral treatment (ART) for HIV-positive patients has expanded rapidly in Asia over the last ten years. Our study aimed to describe the time trends and risk factors for overall survival in patients receiving first-line ART in Asia. Methods We included HIV-positive adult patients who initiated ART between 2003–2013 (n=16 546), from seven sites across six Asia-Pacific countries. Patient follow-up was to May 2014. We compared survival for each country and overall by time period of ART initiation using Kaplan-Meier curves. Factors associated with mortality were assessed using Cox regression, stratified by site. We also summarized first-line ART regimens, CD4 count at ART initiation, and CD4 and HIV viral load testing frequencies. Results There were 880 deaths observed over 54 532 person-years of follow-up, a crude rate of 1.61 (1.51, 1.72) per 100 person-years. Survival significantly improved in more recent years of ART initiation. The survival probabilities at 4 years follow-up for those initiating ART in 2003–05 was 92.1%, 2006–09 was 94.3% and 2010–2013 was 94.5% (p<0.001). Factors associated with higher mortality risk included initiating ART in earlier time periods, older age, male sex, injecting drug use as HIV exposure and lower pre-ART CD4 count. Concurrent with improved survival was increased tenofovir use, ART initiation at higher CD4 counts, and greater monitoring of CD4 and HIV viral load. Conclusions Our results suggest that HIV-positive patients from Asia have improved survival in more recent years of ART initiation. This is likely a consequence of improvements in treatment and, patient management and monitoring over time. PMID:26961354

Overwinter survival of neotropical migratory birds in early successional and mature tropical forests

USGS Publications Warehouse

Conway, C.J.; Powell, G.V.N.; Nichols, J.D.

1995-01-01

Many Neotropical migratory species inhabit both mature and early successional forest on their wintering grounds, yet comparisons of survival rates between habitats are lacking. Consequently, the factors affecting habitat suitability for Neotropical migrants and the potential effects of tropical deforestation on migrants are not well understood. We estimated over-winter survival and capture probabilities of Wood Thrush (Hylocichla mustelina), Ovenbird (Seiurus aurocapillus), Hooded Warbler (Wilsonia citrina), and Kentucky Warbler (Oporomis formosus) inhabiting two common tropical habitat types, mature and early-successional forest. Our results suggest that large differences (for example, ratio of survival rates (gamma) < 0.85) in overwinter survival between these habitats do not exist for any of these species. Age ratios did not differ between habitats, but males were more common in forest habitats and females more common in successional habitats for Hooded Warblers and Kentucky Warblers. Future research on overwinter survival should address the need for age- and sex-specific survival estimates before we can draw strong conclusions regarding winter habitat suitability. Our estimates of over-winter survival extrapolated to annual survival rates that were generally lower than previous estimates of annual survival of migratory birds. Capture probability differed between habitats for Kentucky Warblers, but our results provide strong evidence against large differences in capture probability between habitats for Wood Thrush, Hooded Warblers, and Ovenbirds. We found no temporal or among site differences in survival or capture probability for any of the four species. Additional research is needed to examine the effects of winter habitat use on survival during migration and between-winter survival.

Test for age-specificity in survival of the common tern

USGS Publications Warehouse

Nisbet, I.C.T.; Cam, E.

2002-01-01

Much effort in life-history theory has been addressed to the dependence of life-history traits on age, especially the phenomenon of senescence and its evolution. Although senescent declines in survival are well documented in humans and in domestic and laboratory animals, evidence for their occurrence and importance in wild animal species remains limited and equivocal. Several recent papers have suggested that methodological issues may contribute to this problem, and have encouraged investigators to improve sampling designs and to analyse their data using recently developed approaches to modelling of capture-mark-recapture data. Here we report on a three-year, two-site, mark-recapture study of known-aged common terns (Sterna hirundo) in the north-eastern USA. The study was nested within a long-term ecological study in which large numbers of chicks had been banded in each year for > 25 years. We used a range of models to test the hypothesis of an influence of age on survival probability. We also tested for a possible influence of sex on survival. The cross-sectional design of the study (one year's parameter estimates) avoided the possible confounding of effects of age and time. The study was conducted at a time when one of the study sites was being colonized and numbers were increasing rapidly. We detected two-way movements between the sites and estimated movement probabilities in the year for which they could be modelled. We also obtained limited data on emigration from our study area to more distant sites. We found no evidence that survival depended on either sex or age, except that survival was lower among the youngest birds (ages 2-3 years). Despite the large number of birds included in the study (1599 known-aged birds, 2367 total), confidence limits on estimates of survival probability were wide, especially for the oldest age-classes, so that a slight decline in survival late in life could not have been detected. In addition, the cross-sectional design of this

Impact of breast cancer subtypes on 3-year survival among adolescent and young adult women

PubMed Central

2013-01-01

Introduction Young women have poorer survival after breast cancer than do older women. It is unclear whether this survival difference relates to the unique distribution of hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2)-defined molecular breast cancer subtypes among adolescent and young adult (AYA) women aged 15 to 39 years. The purpose of our study was to examine associations between breast cancer subtypes and short-term survival in AYA women, as well as to determine whether the distinct molecular subtype distribution among AYA women explains the unfavorable overall breast cancer survival statistics reported for AYA women compared with older women. Methods Data for 5,331 AYA breast cancers diagnosed between 2005 and 2009 were obtained from the California Cancer Registry. Survival by subtype (triple-negative; HR+/HER2-; HR+/HER2+; HR-/HER2+) and age-group (AYA versus 40- to 64-year-olds) was analyzed with Cox proportional hazards regression with follow-up through 2010. Results With up to 6 years of follow-up and a mean survival time of 3.1 years (SD = 1.5 years), AYA women diagnosed with HR-/HER + and triple-negative breast cancer experienced a 1.6-fold and 2.7-fold increased risk of death, respectively, from all causes (HR-/HER + hazard ratio: 1.55; 95% confidence interval (CI): 1.10 to 2.18; triple-negative HR: 2.75; 95% CI, 2.06 to 3.66) and breast cancer (HR-/HER + hazard ratio: 1.63; 95% CI, 1.12 to 2.36; triple-negative hazard ratio: 2.71; 95% CI, 1.98 to 3.71) than AYA women with HR+/HER2- breast cancer. AYA women who resided in lower socioeconomic status neighborhoods, had public health insurance, and were of Black, compared with White, race/ethnicity experienced worse survival. This race/ethnicity association was attenuated somewhat after adjusting for breast cancer subtypes (hazard ratio, 1.33; 95% CI, 0.98 to 1.82). AYA women had similar all-cause and breast cancer-specific short-term survival as older women

First estimates of the probability of survival in a small-bodied, high-elevation frog (Boreal Chorus Frog, Pseudacris maculata), or how historical data can be useful

USGS Publications Warehouse

Muths, Erin L.; Scherer, R. D.; Amburgey, S. M.; Matthews, T.; Spencer, A. W.; Corn, P.S.

2016-01-01

In an era of shrinking budgets yet increasing demands for conservation, the value of existing (i.e., historical) data are elevated. Lengthy time series on common, or previously common, species are particularly valuable and may be available only through the use of historical information. We provide first estimates of the probability of survival and longevity (0.67–0.79 and 5–7 years, respectively) for a subalpine population of a small-bodied, ostensibly common amphibian, the Boreal Chorus Frog (Pseudacris maculata (Agassiz, 1850)), using historical data and contemporary, hypothesis-driven information–theoretic analyses. We also test a priori hypotheses about the effects of color morph (as suggested by early reports) and of drought (as suggested by recent climate predictions) on survival. Using robust mark–recapture models, we find some support for early hypotheses regarding the effect of color on survival, but we find no effect of drought. The congruence between early findings and our analyses highlights the usefulness of historical information in providing raw data for contemporary analyses and context for conservation and management decisions.

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

Physical Activity and Other Determinants of Survival in the Oldest Adults.

PubMed

Muscari, Antonio; Bianchi, Giampaolo; Forti, Paola; Giovagnoli, Marco; Magalotti, Donatella; Pandolfi, Paolo; Zoli, Marco

2017-02-01

To determine the role of physical activity as a possible survival determinant in the oldest adults. Prospective, longitudinal, population-based cohort. The Pianoro Study of community-dwelling older adults in three towns in northern Italy. Noninstitutionalized individuals aged 85 and older (n = 500; mean age 89.6 ± 3.1, 65% female). Participants provided information on marital status, educational level, previous work activity, cardiovascular risk factors, previous cardiovascular events, self-rated health, joint pain, and functional status. Physical activity was quantified using the Physical Activity Scale for the Elderly. Seven-year mortality was known for all subjects. During the 7 years of follow-up, 365 subjects died. According to Cox proportional hazards regression, the following factors were found to be independently associated with mortality: PASE score (hazard ratio (HR) = 0.987, 95% confidence interval (CI) = 0.981-0.993, P < .001), male sex (HR = 1.642, 95% CI = 1.411-2.068, P < .001), age in years (HR = 1.077, 95% CI = 1.040-1.116, P < .001), previous stroke (HR = 1.908, 95% CI = 1.362-2.673, P < .001), poor self care (HR = 1.662, 95% CI = 1.231-2.246, P < .001), neck pain (HR = 0.649, 95% CI = 0.497-0.849, P = .002), self rated health (HR = 0.991, 95% CI = 0.985-0.997, P = .002). In the oldest adults, accurate quantification of physical activity may provide important prognostic information. The predictive value of cardiovascular risk factors, except age, male sex, and prior stroke, was confirmed to be negligible. An unexpected inverse association between neck pain and mortality may require further investigation. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.

Gene polymorphisms in folate metabolizing enzymes in adult acute lymphoblastic leukemia: effects on methotrexate-related toxicity and survival

PubMed Central

Ongaro, Alessia; De Mattei, Monica; Della Porta, Matteo Giovanni; Rigolin, GianMatteo; Ambrosio, Cristina; Di Raimondo, Francesco; Pellati, Agnese; Masieri, Federica Francesca; Caruso, Angelo; Catozzi, Linda; Gemmati, Donato

2009-01-01

Background The antifolate agent methotrexate is an important component of maintenance therapy in acute lymphoblastic leukemia, although methotrexate-related toxicity is often a reason for interruption of chemotherapy. Prediction of toxicity is difficult because of inter-individual variability susceptibility to antileukemic agents. Methotrexate interferes with folate metabolism leading to depletion of reduced folates. Design and Methods The aim of this study was to investigate the influence of polymorphisms for folate metabolizing enzymes with respect to toxicity and survival in adult patients with acute lymphoblastic leukemia treated with methotrexate maintenance therapy. To this purpose, we evaluated possible associations between genotype and hematologic and non-hematologic toxicity and effects on survival at 2 years of follow-up in patients with acute lymphoblastic leukemia. Results Polymorphisms in the genes encoding for methylenetetrahydrofolate reductase (MTHFR 677C>T) and in dihydrofolate reductase (DHFR 19 bp deletion) significantly increased the risk of hepatotoxicity in single (odds ratio 5.23, 95% confidence interval 1.13–21.95 and odds ratio 4.57, 95% confidence interval 1.01–20.77, respectively) and in combined analysis (odds ratio 6.82, 95% confidence interval 1.38–33.59). MTHFR 677C>T also increased the risk of leukopenia and gastrointestinal toxicity, whilst thymidylate synthase 28 bp repeat polymorphism increased the risk of anemia (odds ratio 8.48, 95% confidence interval 2.00–36.09). Finally, patients with MTHFR 677TT had a decreased overall survival rate (hazard ratio 2.37, 95% confidence interval 1.46–8.45). Conclusions Genotyping of folate polymorphisms might be useful in adult acute lymphoblastic leukemia to optimize methotrexate therapy, reducing the associated toxicity with possible effects on survival. PMID:19648163

Sociodemographic Disparities in Differentiated Thyroid Cancer Survival Among Adolescents and Young Adults in California

PubMed Central

Grogan, Raymon H.; Parsons, Helen M.; Tao, Li; White, Michael G.; Onel, Kenan; Horn-Ross, Pamela L.

2015-01-01

Background: Few studies have focused on prognostic factors among adolescents and young adults (AYAs) 15 to 39 years of age when diagnosed with differentiated thyroid cancer (DTC). Our study expands upon prior work by including an evaluation of survival among AYA men and by neighborhood socioeconomic status, health insurance, and clinical factors to identify subgroups of young DTC patients at higher risk of mortality. Methods: Data for 16,827 AYA DTC patients diagnosed between 1988 and 2010 were obtained from the California Cancer Registry. Survival, through 2010, by sociodemographic and clinical factors was analyzed using Cox proportional hazards regression. Results: Of the 2.1% of AYAs who died, 16.7% died from thyroid cancer and 21.4% died from a subsequent cancer. In multivariate analyses, older AYAs 35 to 39 year of age (versus 15- to 29-year-olds), men (hazard ratio [HR] 2.77, 95% confidence interval [CI] 1.62–4.72), and AYAs of African American or Hispanic race/ethnicity (versus non-Hispanic whites) had worse thyroid cancer specific survival. In addition, residing in low socioeconomic status neighborhoods (HR 3.11 [CI 1.28–7.56]) and nonmetropolitan areas (HR 5.53 [CI 2.07–14.78]) was associated with worse thyroid cancer–specific survival among AYA men, but not AYA women. Conclusions: Despite the generally good prognosis among AYAs with DTC, we identified subgroups of AYA patients at risk for poor outcomes. Further study of the factors underlying these associations, including possible barriers to receiving high-quality treatment and follow-up care, as well as lifestyle factors, are critical to reducing these disparities. PMID:25778795

Effect of Haloperidol on Survival Among Critically Ill Adults With a High Risk of Delirium: The REDUCE Randomized Clinical Trial.

PubMed

van den Boogaard, Mark; Slooter, Arjen J C; Brüggemann, Roger J M; Schoonhoven, Lisette; Beishuizen, Albertus; Vermeijden, J Wytze; Pretorius, Danie; de Koning, Jan; Simons, Koen S; Dennesen, Paul J W; Van der Voort, Peter H J; Houterman, Saskia; van der Hoeven, J G; Pickkers, Peter; van der Woude, Margaretha C. E.; Besselink, Anna; Hofstra, Lieuwe S; Spronk, Peter E; van den Bergh, Walter; Donker, Dirk W; Fuchs, Malaika; Karakus, Attila; Koeman, M; van Duijnhoven, Mirella; Hannink, Gerjon

2018-02-20

Results of studies on use of prophylactic haloperidol in critically ill adults are inconclusive, especially in patients at high risk of delirium. To determine whether prophylactic use of haloperidol improves survival among critically ill adults at high risk of delirium, which was defined as an anticipated intensive care unit (ICU) stay of at least 2 days. Randomized, double-blind, placebo-controlled investigator-driven study involving 1789 critically ill adults treated at 21 ICUs, at which nonpharmacological interventions for delirium prevention are routinely used in the Netherlands. Patients without delirium whose expected ICU stay was at least a day were included. Recruitment was from July 2013 to December 2016 and follow-up was conducted at 90 days with the final follow-up on March 1, 2017. Patients received prophylactic treatment 3 times daily intravenously either 1 mg (n = 350) or 2 mg (n = 732) of haloperidol or placebo (n = 707), consisting of 0.9% sodium chloride. The primary outcome was the number of days that patients survived in 28 days. There were 15 secondary outcomes, including delirium incidence, 28-day delirium-free and coma-free days, duration of mechanical ventilation, and ICU and hospital length of stay. All 1789 randomized patients (mean, age 66.6 years [SD, 12.6]; 1099 men [61.4%]) completed the study. The 1-mg haloperidol group was prematurely stopped because of futility. There was no difference in the median days patients survived in 28 days, 28 days in the 2-mg haloperidol group vs 28 days in the placebo group, for a difference of 0 days (95% CI, 0-0; P = .93) and a hazard ratio of 1.003 (95% CI, 0.78-1.30, P=.82). All of the 15 secondary outcomes were not statistically different. These included delirium incidence (mean difference, 1.5%, 95% CI, -3.6% to 6.7%), delirium-free and coma-free days (mean difference, 0 days, 95% CI, 0-0 days), and duration of mechanical ventilation, ICU, and hospital length of stay (mean difference

Production and survival of projection neurons in a forebrain vocal center of adult male canaries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kirn, J.R.; Alvarez-Buylla, A.; Nottebohm, F.

1991-06-01

Neurons are produced in the adult canary telencephalon. Many of these cells are incorporated into the high vocal center (nucleus HVC), which participates in the control of learned song. In the present work, 3H-thymidine and fluorogold were employed to follow the differentiation and survival of HVC neurons born in adulthood. We found that many HVC neurons born in September grow long axons to the robust nucleus of the archistriatum (nucleus RA) and thus become part of the efferent pathway for song control. Many of these new neurons have already established their connections with RA by 30 d after their birth.more » By 240 d, 75-80% of the September-born HVC neurons project to RA. Most of these new projection neurons survive at least 8 months. The longevity of HVC neurons born in September suggests that these cells remain part of the vocal control circuit long enough to participate in the yearly renewal of the song repertoire.« less

Dexamethasone and Long-Term Outcome of Tuberculous Meningitis in Vietnamese Adults and Adolescents

PubMed Central

Török, M. Estée; Bang, Nguyen Duc; Chau, Tran Thi Hong; Yen, Nguyen Thi Bich; Thwaites, Guy E.; Thi Quy, Hoang; Dung, Nguyen Huy; Hien, Tran Tinh; Chinh, Nguyen Tran; Thi Thanh Hoang, Hoang; Wolbers, Marcel; Farrar, Jeremy J.

2011-01-01

Background Dexamethasone has been shown to reduce mortality in patients with tuberculous meningitis but the long-term outcome of the disease is unknown. Methods Vietnamese adults and adolescents with tuberculous meningitis recruited to a randomised, double-blind, placebo-controlled trial of adjunctive dexamethasone were followed-up at five years, to determine the effect of dexamethasone on long-term survival and neurological disability. Results 545 patients were randomised to receive either dexamethasone (274 patients) or placebo (271 patients). 50 patients (9.2%) were lost to follow-up at five years. In all patients two-year survival, probabilities tended to be higher in the dexamethasone arm (0.63 versus 0.55; p = 0.07) but five-year survival rates were similar (0.54 versus 0.51, p = 0.51) in both groups. In patients with grade 1 TBM, but not with grade 2 or grade 3 TBM, the benefit of dexamethasone treatment tended to persist over time (five-year survival probabilities 0.69 versus 0.55, p = 0.07) but there was no conclusive evidence of treatment effect heterogeneity by TBM grade (p = 0.36). The dexamethasone group had a similar proportion of severely disabled patients among survivors at five years as the placebo group (17/128, 13.2% vs. 17/116, 14.7%) and there was no significant association between dexamethasone treatment and disability status at five years (p = 0.32). Conclusions Adjunctive dexamethasone appears to improve the probability of survival in patients with TBM, until at least two years of follow-up. We could not demonstrate a five-year survival benefit of dexamethasone treatment which may be confined to patients with grade 1 TBM. Trial Registration ClinicalTrials.gov NCT01317654 NCT01317654?term = tuberculous+meningitis&rank = 3 PMID:22174748

Estimation of Survival Probabilities for Use in Cost-effectiveness Analyses: A Comparison of a Multi-state Modeling Survival Analysis Approach with Partitioned Survival and Markov Decision-Analytic Modeling

PubMed Central

Williams, Claire; Lewsey, James D.; Mackay, Daniel F.; Briggs, Andrew H.

2016-01-01

Modeling of clinical-effectiveness in a cost-effectiveness analysis typically involves some form of partitioned survival or Markov decision-analytic modeling. The health states progression-free, progression and death and the transitions between them are frequently of interest. With partitioned survival, progression is not modeled directly as a state; instead, time in that state is derived from the difference in area between the overall survival and the progression-free survival curves. With Markov decision-analytic modeling, a priori assumptions are often made with regard to the transitions rather than using the individual patient data directly to model them. This article compares a multi-state modeling survival regression approach to these two common methods. As a case study, we use a trial comparing rituximab in combination with fludarabine and cyclophosphamide v. fludarabine and cyclophosphamide alone for the first-line treatment of chronic lymphocytic leukemia. We calculated mean Life Years and QALYs that involved extrapolation of survival outcomes in the trial. We adapted an existing multi-state modeling approach to incorporate parametric distributions for transition hazards, to allow extrapolation. The comparison showed that, due to the different assumptions used in the different approaches, a discrepancy in results was evident. The partitioned survival and Markov decision-analytic modeling deemed the treatment cost-effective with ICERs of just over £16,000 and £13,000, respectively. However, the results with the multi-state modeling were less conclusive, with an ICER of just over £29,000. This work has illustrated that it is imperative to check whether assumptions are realistic, as different model choices can influence clinical and cost-effectiveness results. PMID:27698003

Estimation of Survival Probabilities for Use in Cost-effectiveness Analyses: A Comparison of a Multi-state Modeling Survival Analysis Approach with Partitioned Survival and Markov Decision-Analytic Modeling.

PubMed

Williams, Claire; Lewsey, James D; Mackay, Daniel F; Briggs, Andrew H

2017-05-01

Modeling of clinical-effectiveness in a cost-effectiveness analysis typically involves some form of partitioned survival or Markov decision-analytic modeling. The health states progression-free, progression and death and the transitions between them are frequently of interest. With partitioned survival, progression is not modeled directly as a state; instead, time in that state is derived from the difference in area between the overall survival and the progression-free survival curves. With Markov decision-analytic modeling, a priori assumptions are often made with regard to the transitions rather than using the individual patient data directly to model them. This article compares a multi-state modeling survival regression approach to these two common methods. As a case study, we use a trial comparing rituximab in combination with fludarabine and cyclophosphamide v. fludarabine and cyclophosphamide alone for the first-line treatment of chronic lymphocytic leukemia. We calculated mean Life Years and QALYs that involved extrapolation of survival outcomes in the trial. We adapted an existing multi-state modeling approach to incorporate parametric distributions for transition hazards, to allow extrapolation. The comparison showed that, due to the different assumptions used in the different approaches, a discrepancy in results was evident. The partitioned survival and Markov decision-analytic modeling deemed the treatment cost-effective with ICERs of just over £16,000 and £13,000, respectively. However, the results with the multi-state modeling were less conclusive, with an ICER of just over £29,000. This work has illustrated that it is imperative to check whether assumptions are realistic, as different model choices can influence clinical and cost-effectiveness results.

Long-term survival and conditional survival of cancer patients in Japan using population-based cancer registry data

PubMed Central

Ito, Yuri; Miyashiro, Isao; Ito, Hidemi; Hosono, Satoyo; Chihara, Dai; Nakata-Yamada, Kayo; Nakayama, Masashi; Matsuzaka, Masashi; Hattori, Masakazu; Sugiyama, Hiromi; Oze, Isao; Tanaka, Rina; Nomura, Etsuko; Nishino, Yoshikazu; Matsuda, Tomohiro; Ioka, Akiko; Tsukuma, Hideaki; Nakayama, Tomio

2014-01-01

Although we usually report 5-year cancer survival using population-based cancer registry data, nowadays many cancer patients survive longer and need to be followed-up for more than 5 years. Long-term cancer survival figures are scarce in Japan. Here we report 10-year cancer survival and conditional survival using an established statistical approach. We received data on 1 387 489 cancer cases from six prefectural population-based cancer registries in Japan, diagnosed between 1993 and 2009 and followed-up for at least 5 years. We estimated the 10-year relative survival of patients who were followed-up between 2002 and 2006 using period analysis. Using this 10-year survival, we also calculated the conditional 5-year survival for cancer survivors who lived for some years after diagnosis. We reported 10-year survival and conditional survival of 23 types of cancer for 15–99-year-old patients and four types of cancer for children (0–14 years old) and adolescent and young adults (15–29 years old) patients by sex. Variation in 10-year cancer survival by site was wide, from 5% for pancreatic cancer to 95% for female thyroid cancer. Approximately 70–80% of children and adolescent and young adult cancer patients survived for more than 10 years. Conditional 5-year survival for most cancer sites increased according to years, whereas those for liver cancer and multiple myeloma did not increase. We reported 10-year cancer survival and conditional survival using population-based cancer registries in Japan. It is important for patients and clinicians to report these relevant figures using population-based data. PMID:25183551

Neyman, Markov processes and survival analysis.

PubMed

Yang, Grace

2013-07-01

J. Neyman used stochastic processes extensively in his applied work. One example is the Fix and Neyman (F-N) competing risks model (1951) that uses finite homogeneous Markov processes to analyse clinical trials with breast cancer patients. We revisit the F-N model, and compare it with the Kaplan-Meier (K-M) formulation for right censored data. The comparison offers a way to generalize the K-M formulation to include risks of recovery and relapses in the calculation of a patient's survival probability. The generalization is to extend the F-N model to a nonhomogeneous Markov process. Closed-form solutions of the survival probability are available in special cases of the nonhomogeneous processes, like the popular multiple decrement model (including the K-M model) and Chiang's staging model, but these models do not consider recovery and relapses while the F-N model does. An analysis of sero-epidemiology current status data with recurrent events is illustrated. Fix and Neyman used Neyman's RBAN (regular best asymptotic normal) estimates for the risks, and provided a numerical example showing the importance of considering both the survival probability and the length of time of a patient living a normal life in the evaluation of clinical trials. The said extension would result in a complicated model and it is unlikely to find analytical closed-form solutions for survival analysis. With ever increasing computing power, numerical methods offer a viable way of investigating the problem.

Survival Time of Cross-Match Incompatible Red Blood Cells in Adult Horses.

PubMed

Tomlinson, J E; Taberner, E; Boston, R C; Owens, S D; Nolen-Walston, R D

2015-01-01

There is a markedly reduced half-life of transfused RBCs when donor and recipient cats or humans are cross-match incompatible. Only 10-20% of horses have naturally occurring alloantibodies. Therefore, cross-match testing before blood transfusion is not always performed. Cross-match incompatibility predicts shortened RBC survival time as compared to that of compatible or autologous blood. Twenty healthy adult horses. Prospective trial. Blood type, anti-RBC antibody screen (before and 1 month after transfusion) and major and minor cross-match determined 10 donor-recipient pairs. Two pairs were cross-match compatible, the remainder incompatible. Donor blood (4 L) was collected into citrate phosphate dextrose adenine-1, labeled with NHS-biotin, and transfused into recipients. Samples were collected at 1 hour and 1, 2, 3, 5, 7, 14, 21, 28, and 35 days after transfusion, and biotinylated RBCs were detected by flow cytometry. Horses were monitored for transfusion reaction during transfusion and daily for 5 days. Cross-match incompatibility was significantly associated with decreased RBC survival time (P < .001). The half-life of transfused incompatible (cross-match >1+) allogenic equine RBCs was 4.7 (95% CI, 3.2-6.2) days versus 33.5 (24-43) days for compatible pairings. Cross-match incompatibility was associated with acute febrile transfusion reaction (P = .0083). At day 30, only 1 horse had developed novel anti-RBC antibodies. Cross-match incompatibility was predictive of febrile transfusion reaction and shortened transfused RBC survival, but did not result in production of anti-RBC antibodies at 30 days. Cross-match testing before transfusion is recommended. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Pou4f1 and Pou4f2 Are Dispensable for the Long-Term Survival of Adult Retinal Ganglion Cells in Mice

PubMed Central

Huang, Liang; Hu, Fang; Xie, Xiaoling; Harder, Jeffery; Fernandes, Kimberly; Zeng, Xiang-yun; Libby, Richard; Gan, Lin

2014-01-01

Purpose To investigate the role of Pou4f1 and Pou4f2 in the survival of adult retinal ganglion cells (RGCs). Methods Conditional alleles of Pou4f1 and Pou4f2 were generated (Pou4f1loxP and Pou4f2loxP respectively) for the removal of Pou4f1 and Pou4f2 in adult retinas. A tamoxifen-inducible Cre was used to delete Pou4f1 and Pou4f2 in adult mice and retinal sections and flat mounts were subjected to immunohistochemistry to confirm the deletion of both alleles and to quantify the changes in the number of RGCs and other retinal neurons. To determine the effect of loss of Pou4f1 and Pou4f2 on RGC survival after axonal injury, controlled optic nerve crush (CONC) was performed and RGC death was assessed. Results Pou4f1 and Pou4f2 were ablated two weeks after tamoxifen treatment. Retinal interneurons and Müller glial cells are not affected by the ablation of Pou4f1 or Pou4f2 or both. Although the deletion of both Pou4f1 and Pou4f2 slightly delays the death of RGCs at 3 days post-CONC in adult mice, it does not affect the cell death progress afterwards. Moreoever, deletion of Pou4f1 or Pou4f2 or both has no impact on the long-term viability of RGCs at up to 6 months post-tamoxifen treatment. Conclusion Pou4f1 and Pou4f2 are involved in the acute response to damage to RGCs but are dispensable for the long-term survival of adult RGC in mice. PMID:24736625

Hospital of diagnosis and probability of having surgical treatment for resectable gastric cancer.

PubMed

van Putten, M; Verhoeven, R H A; van Sandick, J W; Plukker, J T M; Lemmens, V E P P; Wijnhoven, B P L; Nieuwenhuijzen, G A P

2016-02-01

Gastric cancer surgery is increasingly being centralized in the Netherlands, whereas the diagnosis is often made in hospitals where gastric cancer surgery is not performed. The aim of this study was to assess whether hospital of diagnosis affects the probability of undergoing surgery and its impact on overall survival. All patients with potentially curable gastric cancer according to stage (cT1/1b-4a, cN0-2, cM0) diagnosed between 2005 and 2013 were selected from The Netherlands Cancer Registry. Multilevel logistic regression was used to examine the probability of undergoing surgery according to hospital of diagnosis. The effect of variation in probability of undergoing surgery among hospitals of diagnosis on overall survival during the intervals 2005-2009 and 2010-2013 was examined by using Cox regression analysis. A total of 5620 patients with potentially curable gastric cancer, diagnosed in 91 hospitals, were included. The proportion of patients who underwent surgery ranged from 53.1 to 83.9 per cent according to hospital of diagnosis (P < 0.001); after multivariable adjustment for patient and tumour characteristics it ranged from 57.0 to 78.2 per cent (P < 0.001). Multivariable Cox regression showed that patients diagnosed between 2010 and 2013 in hospitals with a low probability of patients undergoing curative treatment had worse overall survival (hazard ratio 1.21; P < 0.001). The large variation in probability of receiving surgery for gastric cancer between hospitals of diagnosis and its impact on overall survival indicates that gastric cancer decision-making is suboptimal. © 2015 BJS Society Ltd Published by John Wiley & Sons Ltd.

Predicting long-term graft survival in adult kidney transplant recipients.

PubMed

Pinsky, Brett W; Lentine, Krista L; Ercole, Patrick R; Salvalaggio, Paolo R; Burroughs, Thomas E; Schnitzler, Mark A

2012-07-01

The ability to accurately predict a population's long-term survival has important implications for quantifying the benefits of transplantation. To identify a model that can accurately predict a kidney transplant population's long-term graft survival, we retrospectively studied the United Network of Organ Sharing data from 13,111 kidney-only transplants completed in 1988- 1989. Nineteen-year death-censored graft survival (DCGS) projections were calculated and compared with the population's actual graft survival. The projection curves were created using a two-part estimation model that (1) fits a Kaplan-Meier survival curve immediately after transplant (Part A) and (2) uses truncated observational data to model a survival function for long-term projection (Part B). Projection curves were examined using varying amounts of time to fit both parts of the model. The accuracy of the projection curve was determined by examining whether predicted survival fell within the 95% confidence interval for the 19-year Kaplan-Meier survival, and the sample size needed to detect the difference in projected versus observed survival in a clinical trial. The 19-year DCGS was 40.7% (39.8-41.6%). Excellent predictability (41.3%) can be achieved when Part A is fit for three years and Part B is projected using two additional years of data. Using less than five total years of data tended to overestimate the population's long-term survival, accurate prediction of long-term DCGS is possible, but requires attention to the quantity data used in the projection method.

Volunteering is associated with increased survival in able-bodied participants of the English Longitudinal Study of Ageing.

PubMed

Rogers, Nina Trivedy; Demakakos, Panayotes; Taylor, Mark Steven; Steptoe, Andrew; Hamer, Mark; Shankar, Aparna

2016-06-01

Volunteering has been linked to reduced mortality in older adults, but the mechanisms explaining this effect remain unclear. This study investigated whether volunteering is associated with increased survival in participants of the English Longitudinal Study of Ageing and whether differences in survival are modified by functional disabilities. A multivariate Cox Proportional Hazards model was used to estimate the association of volunteering with survival over a period of 10.9 years in 10 324 participants, while controlling for selected confounders. To investigate effect modification by disability, the analyses were repeated in participants with and without self-reported functional disabilities. Volunteering was associated with a reduced probability of death from all causes in univariate analyses (HR=0.65, CI 0.58 to 0.73, p<0.0001), but adjustment for covariates rendered this association non-significant (HR=0.90, CI 0.79 to 1.01, p=0.07). Able-bodied volunteers had significantly increased survival compared with able-bodied non-volunteers (HR=0.81, 95% CI 0.69 to 0.95, p=0.009). There was no significant survival advantage among disabled volunteers, compared with disabled non-volunteers (HR=1.06, CI 0.88 to 1.29, p=0.53). Volunteering is associated with reduced mortality in older adults in England, but this effect appears to be limited to volunteers who report no disabilities. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Improving the quality of adult mortality data collected in demographic surveys: validation study of a new siblings' survival questionnaire in Niakhar, Senegal.

PubMed

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

2014-05-01

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. 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. 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. Controlled-Trials.com ISRCTN06849961

A faster escape does not enhance survival in zebrafish larvae

PubMed Central

Nair, Arjun; Nguyen, Christy

2017-01-01

An escape response is a rapid manoeuvre used by prey to evade predators. Performing this manoeuvre at greater speed, in a favourable direction, or from a longer distance have been hypothesized to enhance the survival of prey, but these ideas are difficult to test experimentally. We examined how prey survival depends on escape kinematics through a novel combination of experimentation and mathematical modelling. This approach focused on zebrafish (Danio rerio) larvae under predation by adults and juveniles of the same species. High-speed three-dimensional kinematics were used to track the body position of prey and predator and to determine the probability of behavioural actions by both fish. These measurements provided the basis for an agent-based probabilistic model that simulated the trajectories of the animals. Predictions of survivorship by this model were found by Monte Carlo simulations to agree with our observations and we examined how these predictions varied by changing individual model parameters. Contrary to expectation, we found that survival may not be improved by increasing the speed or altering the direction of the escape. Rather, zebrafish larvae operate with sufficiently high locomotor performance due to the relatively slow approach and limited range of suction feeding by fish predators. We did find that survival was enhanced when prey responded from a greater distance. This is an ability that depends on the capacity of the visual and lateral line systems to detect a looming threat. Therefore, performance in sensing, and not locomotion, is decisive for improving the survival of larval fish prey. These results offer a framework for understanding the evolution of predator–prey strategy that may inform prey survival in a broad diversity of animals. PMID:28404783

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.

An adult spindle cell rhabdomyosarcoma in the head and neck region with long-term survival: a case report

PubMed Central

2014-01-01

Introduction Spindle cell rhabdomyosarcoma of the head and neck is a very rare tumor in adults. We report on one case with long-term survival. Case presentation A 41-year-old nonsmoking Caucasian man presented in June 2007 with a painless swelling under his tongue. A diagnosis of a soft tissue sarcoma, and a myofibrosarcoma in particular, was made via biopsy. After multimodal treatment, including local and systemic therapy, our patient remained disease-free until September 2010. The local recurrence was treated unsuccessfully with various chemotherapy regimens. In September 2011, our patient underwent surgical resection again, and a spindle cell rhabdomyosarcoma was diagnosed. To analyze the mismatch between the original diagnosis of a myofibrosarcoma and the second diagnosis, the two specimens were reassessed, and a final diagnosis of a spindle cell rhabdomyosarcoma was made. In 2012 and 2013, our patient suffered further recurrences that were surgically treated, and he is still alive with disease six years and 10 months after the initial diagnosis in June 2007. Conclusions In adults, the spindle cell rhabdomyosarcoma tumor is very rare in the head and neck region. In contrast to childhood tumors, spindle cell rhabdomyosarcoma in adulthood is often associated with a poor prognosis. In the present case, the radical surgical treatment might have helped to prolong the patient’s overall survival, which has lasted more than six years. To our knowledge, this is the longest overall survival reported so far for this tumor entity in the head and neck region. PMID:24946859

Spring and summer survival of female mallards from northcentral Minnesota

USGS Publications Warehouse

Kirby, R.E.; Cowardin, L.M.

1986-01-01

Seasonal survival of 109 adult female mallards (Anas platyrhynchos) fitted with radio transmitters was evaluated in northcentral Minnesota during 1968-74. Survival rates for the 169-day breeding and postbreeding period were: 1.0 during nest initiation (36 days), 0.798 during incubation (28 days), 0.943 during brood rearing (51 days), 0.947 during molt (26 days), and 1.0 during premigration (28 days). Survival for the 169-day spring-summer period was 0.713 for adult females remaining on the study area. Fall-winter survival was estimated at 0.881 for those adult birds remaining on the study area throughout the summer. The data confirm speculation on relative risk to females of various phases of the mallard reproductive cycle and support previous conclusions that the northcentral Minnesota breeding mallard population is not self sustaining. The value of learning further details of processes affecting specific seasonal mortality factors for both adult and young waterfowl is emphasized.

Azadirachtin effects on mating success, gametic abnormalities and progeny survival in Drosophila melanogaster (Diptera).

PubMed

Oulhaci, Chemseddine M; Denis, Béatrice; Kilani-Morakchi, Samira; Sandoz, Jean-Christophe; Kaiser, Laure; Joly, Dominique; Aribi, Nadia

2018-01-01

Azadirachtin is a prominent natural pesticide and represents an alternative to conventional insecticides. It has been successfully used against insect pests. However, its effects on reproduction require further analysis. Here we investigated lethal and sublethal effects of azadirachtin, on treated adults in a model insect, Drosophila melanogaster (Meigen). Dose-mortality relationships as well as several parameters of reproduction (mating, spermatogenesis, oogenesis and fertility) were examined. Neem-Azal, a commercial formulation of azadirachtin, applied topically on newly emerged adults, increased mortality with a positive dose-dependent relationship. The LD 50 (0.63 μg) was determined 24 h after treatment using a non-linear regression. Adults surviving this dose had a mating success that was divided by 3 and a progeny production reduced by half when males were treated, and even more when females were treated. When combining probability of survival, of mating and reduced progeny, it appeared that LD 50 induced a 98% reduction in reproductive rates. Reduced progeny was partially explained by the effect of adult treatment on gametes number and abnormalities. The number of cysts and the apical nuclei positions within the cysts decreased by 29.7% and 20%, respectively, in males. In females, the number of oocytes per ovary and the volume of basal oocytes also decreased by 16.1% and 32.4%, respectively. Azadirachtin causes significant toxic effects in both sexes and decreases the fecundity and fertility of D. melanogaster. Females are more sensitive to azadirachtin. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Semiparametric temporal process regression of survival-out-of-hospital.

PubMed

Zhan, Tianyu; Schaubel, Douglas E

2018-05-23

The recurrent/terminal event data structure has undergone considerable methodological development in the last 10-15 years. An example of the data structure that has arisen with increasing frequency involves the recurrent event being hospitalization and the terminal event being death. We consider the response Survival-Out-of-Hospital, defined as a temporal process (indicator function) taking the value 1 when the subject is currently alive and not hospitalized, and 0 otherwise. Survival-Out-of-Hospital is a useful alternative strategy for the analysis of hospitalization/survival in the chronic disease setting, with the response variate representing a refinement to survival time through the incorporation of an objective quality-of-life component. The semiparametric model we consider assumes multiplicative covariate effects and leaves unspecified the baseline probability of being alive-and-out-of-hospital. Using zero-mean estimating equations, the proposed regression parameter estimator can be computed without estimating the unspecified baseline probability process, although baseline probabilities can subsequently be estimated for any time point within the support of the censoring distribution. We demonstrate that the regression parameter estimator is asymptotically normal, and that the baseline probability function estimator converges to a Gaussian process. Simulation studies are performed to show that our estimating procedures have satisfactory finite sample performances. The proposed methods are applied to the Dialysis Outcomes and Practice Patterns Study (DOPPS), an international end-stage renal disease study.

Effects of weather on survival in populations of boreal toads in Colorado

USGS Publications Warehouse

Scherer, R. D.; Muths, E.; Lambert, B.A.

2008-01-01

Understanding the relationships between animal population demography and the abiotic and biotic elements of the environments in which they live is a central objective in population ecology. For example, correlations between weather variables and the probability of survival in populations of temperate zone amphibians may be broadly applicable to several species if such correlations can be validated for multiple situations. This study focuses on the probability of survival and evaluates hypotheses based on six weather variables in three populations of Boreal Toads (Bufo boreas) from central Colorado over eight years. In addition to suggesting a relationship between some weather variables and survival probability in Boreal Toad populations, this study uses robust methods and highlights the need for demographic estimates that are precise and have minimal bias. Capture-recapture methods were used to collect the data, and the Cormack-Jolly-Seber model in program MARK was used for analysis. The top models included minimum daily winter air temperature, and the sum of the model weights for these models was 0.956. Weaker support was found for the importance of snow depth and the amount of environmental moisture in winter in modeling survival probability. Minimum daily winter air temperature was positively correlated with the probability of survival in Boreal Toads at other sites in Colorado and has been identified as an important covariate in studies in other parts of the world. If air temperatures are an important component of survival for Boreal Toads or other amphibians, changes in climate may have profound impacts on populations. Copyright 2008 Society for the Study of Amphibians and Reptiles.

Exact calculations of survival probability for diffusion on growing lines, disks, and spheres: The role of dimension.

PubMed

Simpson, Matthew J; Baker, Ruth E

2015-09-07

Unlike standard applications of transport theory, the transport of molecules and cells during embryonic development often takes place within growing multidimensional tissues. In this work, we consider a model of diffusion on uniformly growing lines, disks, and spheres. An exact solution of the partial differential equation governing the diffusion of a population of individuals on the growing domain is derived. Using this solution, we study the survival probability, S(t). For the standard non-growing case with an absorbing boundary, we observe that S(t) decays to zero in the long time limit. In contrast, when the domain grows linearly or exponentially with time, we show that S(t) decays to a constant, positive value, indicating that a proportion of the diffusing substance remains on the growing domain indefinitely. Comparing S(t) for diffusion on lines, disks, and spheres indicates that there are minimal differences in S(t) in the limit of zero growth and minimal differences in S(t) in the limit of fast growth. In contrast, for intermediate growth rates, we observe modest differences in S(t) between different geometries. These differences can be quantified by evaluating the exact expressions derived and presented here.

Estimating survival probabilities by exposure levels: utilizing vital statistics and complex survey data with mortality follow-up.

PubMed

Landsman, V; Lou, W Y W; Graubard, B I

2015-05-20

We present a two-step approach for estimating hazard rates and, consequently, survival probabilities, by levels of general categorical exposure. The resulting estimator utilizes three sources of data: vital statistics data and census data are used at the first step to estimate the overall hazard rate for a given combination of gender and age group, and cohort data constructed from a nationally representative complex survey with linked mortality records, are used at the second step to divide the overall hazard rate by exposure levels. We present an explicit expression for the resulting estimator and consider two methods for variance estimation that account for complex multistage sample design: (1) the leaving-one-out jackknife method, and (2) the Taylor linearization method, which provides an analytic formula for the variance estimator. The methods are illustrated with smoking and all-cause mortality data from the US National Health Interview Survey Linked Mortality Files, and the proposed estimator is compared with a previously studied crude hazard rate estimator that uses survey data only. The advantages of a two-step approach and possible extensions of the proposed estimator are discussed. Copyright © 2015 John Wiley & Sons, Ltd.

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.

Survival of juvenile black brant during brood rearing

USGS Publications Warehouse

Flint, Paul L.; Sedinger, James S.; Pollock, Kenneth H.

1995-01-01

Survival of young is an important and poorly understood component of waterfowl productivity. We estimated survival of black brant (Branta bernicla nigricans) goslings during summers 1987-89 on the Yukon-Kuskokwim Delta, Alaska, to determine timing and magnitude of gosling mortality and to compare methods of estimating gosling survival. Eighty-two percent of radio-tagged adult females (n = 61) fledged ≥1 gosling (brood success). We estimated survival of goslings within broods by 3 methods: (1) changes in mean brood size through time, (2) observation of goslings associated with marked adults, and (3) age ratios of brant captured in banding drives. Estimates of gosling survival within successful broods averaged 81% and ranged from 66 to 92%. Combining brood success and gosling survival within successful broods yielded estimates of overall gosling survival that averaged 68%, ranging from 79% in 1987 to 56% in 1989. Eighty-two percent of gosling mortality occurred in the first 15 days. Estimates of survival on the basis of age ratios of birds captured in banding drives are biased low. Our estimates of average gosling survival are higher than reported for other species of geese.

Survival estimation and the effects of dependency among animals

USGS Publications Warehouse

Schmutz, Joel A.; Ward, David H.; Sedinger, James S.; Rexstad, Eric A.

1995-01-01

Survival models assume that fates of individuals are independent, yet the robustness of this assumption has been poorly quantified. We examine how empirically derived estimates of the variance of survival rates are affected by dependency in survival probability among individuals. We used Monte Carlo simulations to generate known amounts of dependency among pairs of individuals and analyzed these data with Kaplan-Meier and Cormack-Jolly-Seber models. Dependency significantly increased these empirical variances as compared to theoretically derived estimates of variance from the same populations. Using resighting data from 168 pairs of black brant, we used a resampling procedure and program RELEASE to estimate empirical and mean theoretical variances. We estimated that the relationship between paired individuals caused the empirical variance of the survival rate to be 155% larger than the empirical variance for unpaired individuals. Monte Carlo simulations and use of this resampling strategy can provide investigators with information on how robust their data are to this common assumption of independent survival probabilities.

Survival of Near-Critical Branching Brownian Motion

NASA Astrophysics Data System (ADS)

Berestycki, Julien; Berestycki, Nathanaël; Schweinsberg, Jason

2011-06-01

Consider a system of particles performing branching Brownian motion with negative drift μ= sqrt{2 - \\varepsilon} and killed upon hitting zero. Initially there is one particle at x>0. Kesten (Stoch. Process. Appl. 7:9-47, 1978) showed that the process survives with positive probability if and only if ɛ>0. Here we are interested in the asymptotics as ɛ→0 of the survival probability Q μ ( x). It is proved that if L=π/sqrt{\\varepsilon} then for all x∈ℝ, lim ɛ→0 Q μ ( L+ x)= θ( x)∈(0,1) exists and is a traveling wave solution of the Fisher-KPP equation. Furthermore, we obtain sharp asymptotics of the survival probability when x< L and L- x→∞. The proofs rely on probabilistic methods developed by the authors in (Berestycki et al. in arXiv: 1001.2337, 2010). This completes earlier work by Harris, Harris and Kyprianou (Ann. Inst. Henri Poincaré Probab. Stat. 42:125-145, 2006) and confirms predictions made by Derrida and Simon (Europhys. Lett. 78:60006, 2007), which were obtained using nonrigorous PDE methods.

Selectivity assessment of two biorational insecticides, azadirachtin and pyriproxyfen, in comparison to a neonicotinoid, acetamiprid, on pupae and adults of a Neotropical strain Eretmocerus mundus Mercet.

PubMed

Francesena, Natalia; Schneider, Marcela Inés

2018-05-02

Assessment of the susceptibility of natural enemies of pests to selective pesticides is relevant for a sustainable agriculture with low impact on the environment. The aim of this study was to assess the toxicity of two biorational insecticides, azadirachtin and pyriproxyfen in comparison to a neonicotinoid insecticide, acetamiprid, on pupae and adults of a Neotropical strain of Eretmocerus mundus. Adult emergence and survival were evaluated as lethal effects whereas the sublethal effects were assessed through the reproductive capacity, sex ratio, and longevity of the surviving first progeny. Adult emergence from treated pupae was reduced by all three insecticides, but azadirachtin at its maximum field recommended concentration (MFRC) proved the most toxic insecticide. The survival probability of emerged adults was reduced by the three insecticides below than 50% from 2 to 5 days after the adult emergence. Malformations in nonemerged adults from treated pupal hosts were observed at the MFRC of all three insecticides. Sublethal effects on survivors from pupal treatment could be evaluated at only the lowest azadirachtin concentration. At that concentration, though azadirachtin did not affect the reproductive capacity of females, the sex ratio and the longevity of the first progeny were disrupted. The survival of parasitoid adults after adult exposure was reduced by all three insecticides, pyriproxyfen at the MFRC being the most toxic. All insecticides at their half of MFRCs induced sublethal effects in the survivors' adults, with pyriproxyfen being the most harmful to the reproductive capacity of females. In conclusion, both biorational insecticides were toxic to E. mundus. Copyright © 2018 Elsevier Ltd. All rights reserved.

Conditional long-term survival following minimally invasive robotic mitral valve repair: a health services perspective.

PubMed

Efird, Jimmy T; Griffin, William F; Gudimella, Preeti; O'Neal, Wesley T; Davies, Stephen W; Crane, Patricia B; Anderson, Ethan J; Kindell, Linda C; Landrine, Hope; O'Neal, Jason B; Alwair, Hazaim; Kypson, Alan P; Nifong, Wiley L; Chitwood, W Randolph

2015-09-01

Conditional survival is defined as the probability of surviving an additional number of years beyond that already survived. The aim of this study was to compute conditional survival in patients who received a robotically assisted, minimally invasive mitral valve repair procedure (RMVP). Patients who received RMVP with annuloplasty band from May 2000 through April 2011 were included. A 5- and 10-year conditional survival model was computed using a multivariable product-limit method. Non-smoking men (≤65 years) who presented in sinus rhythm had a 96% probability of surviving at least 10 years if they survived their first year following surgery. In contrast, recent female smokers (>65 years) with preoperative atrial fibrillation only had an 11% probability of surviving beyond 10 years if alive after one year post-surgery. In the context of an increasingly managed healthcare environment, conditional survival provides useful information for patients needing to make important treatment decisions, physicians seeking to select patients most likely to benefit long-term following RMVP, and hospital administrators needing to comparatively assess the life-course economic value of high-tech surgical procedures.

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.

Juvenile survival in a tropical population of roseate terns: Interannual variation and effect of tick parasitism

USGS Publications Warehouse

Monticelli, David; Ramos, Jaime A.; Hines, James E.; Nichols, James D.; Spendelow, Jeffrey 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

In vitro cultivation of anisakis simplex: pepsin increases survival and moulting from fourth larval to adult stage.

PubMed

Iglesias, L; Valero, A; Benítez, R; Adroher, F J

2001-09-01

This paper describes the in vitro cultivation of the 3rd-larval stage (L3) of Anisakis simplex to adulthood in a much simpler and easier to prepare medium than those described to date. The adult males obtained are between 3.8 and 6.5 cm long and the females between 4.5 and 8.0 cm. Some individually cultivated females laid eggs which had an average size of 44.4 x 50.5 microm. The culture conditions were as follows: medium RPMI-1640 supplemented with 20% heat-inactivated fetal bovine serum and 1% commercial pepsin, at pH 4.0 and a temperature of 37 degrees C, and in air atmosphere with 5% CO2. The pepsin was found to be the key to the success of the culture. The average survival of the worms in the culture increased from 50 to 88 days, due to the fact that the survival of the adults practically doubled (increasing by 1.9 times). Furthermore, the number of worms that completed the 4th moulting (M4) increased by 4.2 times, from 22.9 to 95.6%. This culture medium may facilitate, due to its simplicity, the study of anisakids, or at least of A. simplex, constituting another step towards achieving a complete in vitro life-cycle for these parasites.

Attitudes toward Bisexual Men and Women among a Nationally Representative Probability Sample of Adults in the United States.

PubMed

Dodge, Brian; Herbenick, Debby; Friedman, M Reuel; Schick, Vanessa; Fu, Tsung-Chieh Jane; Bostwick, Wendy; Bartelt, Elizabeth; Muñoz-Laboy, Miguel; Pletta, David; Reece, Michael; Sandfort, Theo G M

2016-01-01

As bisexual individuals in the United States (U.S.) face significant health disparities, researchers have posited that these differences may be fueled, at least in part, by negative attitudes, prejudice, stigma, and discrimination toward bisexual individuals from heterosexual and gay/lesbian individuals. Previous studies of individual and social attitudes toward bisexual men and women have been conducted almost exclusively with convenience samples, with limited generalizability to the broader U.S. Our study provides an assessment of attitudes toward bisexual men and women among a nationally representative probability sample of heterosexual, gay, lesbian, and other-identified adults in the U.S. Data were collected from the 2015 National Survey of Sexual Health and Behavior (NSSHB), via an online questionnaire with a probability sample of adults (18 years and over) from throughout the U.S. We included two modified 5-item versions of the Bisexualities: Indiana Attitudes Scale (BIAS), validated sub-scales that were developed to measure attitudes toward bisexual men and women. Data were analyzed using descriptive statistics, gamma regression, and paired t-tests. Gender, sexual identity, age, race/ethnicity, income, and educational attainment were all significantly associated with participants' attitudes toward bisexual individuals. In terms of responses to individual scale items, participants were most likely to "neither agree nor disagree" with all attitudinal statements. Across sexual identities, self-identified other participants reported the most positive attitudes, while heterosexual male participants reported the least positive attitudes. As in previous research on convenience samples, we found a wide range of demographic characteristics were related with attitudes toward bisexual individuals in our nationally-representative study of heterosexual, gay/lesbian, and other-identified adults in the U.S. In particular, gender emerged as a significant characteristic

Migration confers winter survival benefits in a partially migratory songbird

PubMed Central

Zúñiga, Daniel; Gager, Yann; Kokko, Hanna; Fudickar, Adam Michael; Schmidt, Andreas; Naef-Daenzer, Beat; Wikelski, Martin

2017-01-01

To evolve and to be maintained, seasonal migration, despite its risks, has to yield fitness benefits compared with year-round residency. Empirical data supporting this prediction have remained elusive in the bird literature. To test fitness related benefits of migration, we studied a partial migratory population of European blackbirds (Turdus merula) over 7 years. Using a combination of capture-mark-recapture and radio telemetry, we compared survival probabilities between migrants and residents estimated by multi-event survival models, showing that migrant blackbirds had 16% higher probability to survive the winter compared to residents. A subsequent modelling exercise revealed that residents should have 61.25% higher breeding success than migrants, to outweigh the survival costs of residency. Our results support theoretical models that migration should confer survival benefits to evolve, and thus provide empirical evidence to understand the evolution and maintenance of migration. PMID:29157357

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

Age, Loss Minimization, and the Role of Probability for Decision-Making.

PubMed

Best, Ryan; Freund, Alexandra M

2018-04-05

Older adults are stereotypically considered to be risk averse compared to younger age groups, although meta-analyses on age and the influence of gain/loss framing on risky choices have not found empirical evidence for age differences in risk-taking. The current study extends the investigation of age differences in risk preference by including analyses on the effect of the probability of a risky option on choices in gain versus loss situations. Participants (n = 130 adults aged 19-80 years) chose between a certain option and a risky option of varying probability in gain- and loss-framed gambles with actual monetary outcomes. Only younger adults displayed an overall framing effect. Younger and older adults responded differently to probability fluctuations depending on the framing condition. Older adults were more likely to choose the risky option as the likelihood of avoiding a larger loss increased and as the likelihood of a larger gain decreased. Younger adults responded with the opposite pattern: they were more likely to choose the risky option as the likelihood of a larger gain increased and as the likelihood of avoiding a (slightly) larger loss decreased. Results suggest that older adults are more willing to select a risky option when it increases the likelihood that larger losses be avoided, whereas younger adults are more willing to select a risky option when it allows for slightly larger gains. This finding supports expectations based on theoretical accounts of goal orientation shifting away from securing gains in younger adulthood towards maintenance and avoiding losses in older adulthood. Findings are also discussed in respect to the affective enhancement perspective and socioemotional selectivity theory. © 2018 S. Karger AG, Basel.

Social class and survival on the S.S. Titanic.

PubMed

Hall, W

1986-01-01

Passengers' chances of surviving the sinking of the S.S. Titanic were related to their sex and their social class: females were more likely to survive than males, and the chances of survival declined with social class as measured by the class in which the passenger travelled. The probable reasons for these differences in rates of survival are discussed as are the reasons accepted by the Mersey Committee of Inquiry into the sinking.

Reduction in deformed wing virus infection in larval and adult honey bees (Apis mellifera L.) by double-stranded RNA ingestion.

PubMed

Desai, S D; Eu, Y-J; Whyard, S; Currie, R W

2012-08-01

Deformed wing virus (DWV) is a serious pathogen of the honey bee, Apis mellifera L., vectored by the parasitic mite Varroa destructor. The virus is associated with wing deformity in symptomatic bees, and premature death and reduced colony performance in asymptomatic bees. In the present study we reduced DWV infection by feeding both first instar larvae and adult A. mellifera with a double-stranded (ds) RNA construct, DWV-dsRNA, which is specific to DWV in DWV-inoculated bees, by mixing it with their food. We showed that feeding DWV to larvae causes wing deformity in adult bees in the absence of varroa mites and decreases survival rates of adult bees relative to bees not fed DWV. Feeding larvae with DWV-dsRNA in advance of inoculation with virus reduced the DWV viral level and reduced wing deformity relative to larvae fed DWV or DWV with green fluorescent protein-dsRNA (probably a result of RNA silencing), but did not affect survival to the adult stage. Feeding DWV-dsRNA did not affect larval survival rates, which suggests that dsRNA is non-toxic to larvae. Feeding adult workers with DWV-dsRNA in advance of inoculation with virus increased their longevity and reduced DWV concentration relative to controls. © 2012 The Authors. Insect Molecular Biology © 2012 The Royal Entomological Society.

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.

Melanophore migration and survival during zebrafish adult pigment stripe development require the immunoglobulin superfamily adhesion molecule Igsf11.

PubMed

Eom, Dae Seok; Inoue, Shinya; Patterson, Larissa B; Gordon, Tiffany N; Slingwine, Rebecca; Kondo, Shigeru; Watanabe, Masakatsu; Parichy, David M

2012-01-01

The zebrafish adult pigment pattern has emerged as a useful model for understanding the development and evolution of adult form as well as pattern-forming mechanisms more generally. In this species, a series of horizontal melanophore stripes arises during the larval-to-adult transformation, but the genetic and cellular bases for stripe formation remain largely unknown. Here, we show that the seurat mutant phenotype, consisting of an irregular spotted pattern, arises from lesions in the gene encoding Immunoglobulin superfamily member 11 (Igsf11). We find that Igsf11 is expressed by melanophores and their precursors, and we demonstrate by cell transplantation and genetic rescue that igsf11 functions autonomously to this lineage in promoting adult stripe development. Further analyses of cell behaviors in vitro, in vivo, and in explant cultures ex vivo demonstrate that Igsf11 mediates adhesive interactions and that mutants for igsf11 exhibit defects in both the migration and survival of melanophores and their precursors. These findings identify the first in vivo requirements for igsf11 as well as the first instance of an immunoglobulin superfamily member functioning in pigment cell development and patterning. Our results provide new insights into adult pigment pattern morphogenesis and how cellular interactions mediate pattern formation.

Melanophore Migration and Survival during Zebrafish Adult Pigment Stripe Development Require the Immunoglobulin Superfamily Adhesion Molecule Igsf11

PubMed Central

Patterson, Larissa B.; Gordon, Tiffany N.; Slingwine, Rebecca; Kondo, Shigeru; Watanabe, Masakatsu; Parichy, David M.

2012-01-01

The zebrafish adult pigment pattern has emerged as a useful model for understanding the development and evolution of adult form as well as pattern-forming mechanisms more generally. In this species, a series of horizontal melanophore stripes arises during the larval-to-adult transformation, but the genetic and cellular bases for stripe formation remain largely unknown. Here, we show that the seurat mutant phenotype, consisting of an irregular spotted pattern, arises from lesions in the gene encoding Immunoglobulin superfamily member 11 (Igsf11). We find that Igsf11 is expressed by melanophores and their precursors, and we demonstrate by cell transplantation and genetic rescue that igsf11 functions autonomously to this lineage in promoting adult stripe development. Further analyses of cell behaviors in vitro, in vivo, and in explant cultures ex vivo demonstrate that Igsf11 mediates adhesive interactions and that mutants for igsf11 exhibit defects in both the migration and survival of melanophores and their precursors. These findings identify the first in vivo requirements for igsf11 as well as the first instance of an immunoglobulin superfamily member functioning in pigment cell development and patterning. Our results provide new insights into adult pigment pattern morphogenesis and how cellular interactions mediate pattern formation. PMID:22916035

Population trends, survival, and sampling methodologies for a population of Rana draytonii

USGS Publications Warehouse

Fellers, Gary M.; Kleeman, Patrick M.; Miller, David A.W.; Halstead, Brian J.

2017-01-01

Estimating population trends provides valuable information for resource managers, but monitoring programs face trade-offs between the quality and quantity of information gained and the number of sites surveyed. We compared the effectiveness of monitoring techniques for estimating population trends of Rana draytonii (California Red-legged Frog) at Point Reyes National Seashore, California, USA, over a 13-yr period. Our primary goals were to: 1) estimate trends for a focal pond at Point Reyes National Seashore, and 2) evaluate whether egg mass counts could reliably estimate an index of abundance relative to more-intensive capture–mark–recapture methods. Capture–mark–recapture (CMR) surveys of males indicated a stable population from 2005 to 2009, despite low annual apparent survival (26.3%). Egg mass counts from 2000 to 2012 indicated that despite some large fluctuations, the breeding female population was generally stable or increasing, with annual abundance varying between 26 and 130 individuals. Minor modifications to egg mass counts, such as marking egg masses, can allow estimation of egg mass detection probabilities necessary to convert counts to abundance estimates, even when closure of egg mass abundance cannot be assumed within a breeding season. High egg mass detection probabilities (mean per-survey detection probability = 0.98 [0.89–0.99]) indicate that egg mass surveys can be an efficient and reliable method for monitoring population trends of federally threatened R. draytonii. Combining egg mass surveys to estimate trends at many sites with CMR methods to evaluate factors affecting adult survival at focal populations is likely a profitable path forward to enhance understanding and conservation of R. draytonii.

Comparison of Wells and Revised Geneva Rule to Assess Pretest Probability of Pulmonary Embolism in High-Risk Hospitalized Elderly Adults.

PubMed

Di Marca, Salvatore; Cilia, Chiara; Campagna, Andrea; D'Arrigo, Graziella; Abd ElHafeez, Samar; Tripepi, Giovanni; Puccia, Giuseppe; Pisano, Marcella; Mastrosimone, Gianluca; Terranova, Valentina; Cardella, Antonella; Buonacera, Agata; Stancanelli, Benedetta; Zoccali, Carmine; Malatino, Lorenzo

2015-06-01

To assess and compare the diagnostic power for pulmonary embolism (PE) of Wells and revised Geneva scores in two independent cohorts (training and validation groups) of elderly adults hospitalized in a non-emergency department. Prospective clinical study, January 2011 to January 2013. Unit of Internal Medicine inpatients, University of Catania, Italy. Elderly adults (mean age 76 ± 12), presenting with dyspnea or chest pain and with high clinical probability of PE or D-dimer values greater than 500 ng/mL (N = 203), were enrolled and consecutively assigned to a training (n = 101) or a validation (n = 102) group. The clinical probability of PE was assessed using Wells and revised Geneva scores. Clinical examination, D-dimer test, and multidetector computed angiotomography were performed in all participants. The accuracy of the scores was assessed using receiver operating characteristic analyses. PE was confirmed in 46 participants (23%) (24 training group, 22 validation group). In the training group, the area under the receiver operating characteristic curve was 0.91 (95% confidence interval (CI) = 0.85-0.98) for the Wells score and 0.69 (95% CI = 0.56-0.82) for the revised Geneva score (P < .001). These results were confirmed in the validation group (P < .05). The positive (LR+) and negative likelihood ratios (LR-) (two indices combining sensitivity and specificity) of the Wells score were superior to those of the revised Geneva score in the training (LR+, 7.90 vs 1.34; LR-, 0.23 vs 0.66) and validation (LR+, 13.5 vs 1.46; LR-, 0.47 vs 0.54) groups. In high-risk elderly hospitalized adults, the Wells score is more accurate than the revised Geneva score for diagnosing PE. © 2015, Copyright the Authors Journal compilation © 2015, The American Geriatrics Society.

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

PubMed

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

Adults with sickle cell anemia (HbSS) are inconsistently treated with hydroxyurea. 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. 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. 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. Our data suggest that adults should be treated with the maximum tolerated hydroxyurea dose, ideally

Chronic treatment with AMPA receptor potentiator Org 26576 increases neuronal cell proliferation and survival in adult rodent hippocampus.

PubMed

Su, Xiaowei W; Li, Xiao-Yuan; Banasr, Mounira; Koo, Ja Wook; Shahid, Mohammed; Henry, Brian; Duman, Ronald S

2009-10-01

Currently available antidepressants upregulate hippocampal neurogenesis and prefrontal gliogenesis after chronic administration, which could block or reverse the effects of stress. Allosteric alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor potentiators (ARPs), which have novel targets compared to current antidepressants, have been shown to have antidepressant properties in neurogenic and behavioral models. This study analyzed the effect of the ARP Org 26576 on the proliferation, survival, and differentiation of neurons and glia in the hippocampus and prelimbic cortex of adult rats. Male Sprague-Dawley rats received acute (single day) or chronic (21 day) twice-daily intraperitoneal injections of Org 26576 (1-10 mg/kg). Bromodeoxyuridine (BrdU) immunohistochemistry was conducted 24 h or 28 days after the last drug injection for the analysis of cell proliferation or survival, respectively. Confocal immunofluorescence analysis was used to determine the phenotype of surviving cells. Acute administration of Org 26576 did not increase neuronal cell proliferation. However, chronic administration of Org 26576 increased progenitor cell proliferation in dentate gyrus (approximately 40%) and in prelimbic cortex (approximately 35%) at the 10-mg/kg dosage. Cells born in response to chronic Org 26576 in dentate gyrus exhibited increased rates of survival (approximately 30%) with the majority of surviving cells expressing a neuronal phenotype. Findings suggest that Org 26576 may have antidepressant properties, which may be attributed, in part, to upregulation of hippocampal neurogenesis and prelimbic cell proliferation.

Outcomes of allogeneic hematopoietic cell transplantation for adolescent and young adults compared with children and older adults with acute myeloid leukemia.

PubMed

Majhail, Navneet S; Brazauskas, Ruta; Hassebroek, Anna; Bredeson, Christopher N; Hahn, Theresa; Hale, Gregory A; Horowitz, Mary M; Lazarus, Hillard M; Maziarz, Richard T; Wood, William A; Parsons, Susan K; Joffe, Steven; Rizzo, J Douglas; Lee, Stephanie J; Hayes-Lattin, Brandon M

2012-06-01

Adolescents and young adults (AYAs) with cancer have not experienced improvements in survival to the same extent as children and older adults. We compared outcomes among children (<15 years), AYAs (15-40 years) and older adults (>40 years) receiving allogeneic hematopoietic cell transplant (HCT) for acute myeloid leukemia (AML). Our cohort consisted of 900 children, 2,708 AYA, and 2,728 older adult recipients of HLA-identical sibling or unrelated donor (URD) transplantation using myeloablative or reduced-intensity/nonmyeloablative conditioning. Outcomes were assessed over three time periods (1980-1988, 1989-1997, 1998-2005) for siblings and two time periods (1989-1997, 1998-2005) for URD HCT. Analyses were stratified by donor type. Results showed overall survival for AYAs using either siblings or URD improved over time. Although children had better and older adults had worse survival compared with AYAs, improvements in survival for AYAs did not lag behind those for children and older adults. After sibling donor HCT, 5-year adjusted survival for the three time periods was 40%, 48%, and 53% for children, 35%, 41%, and 42% for AYAs, and 22%, 30%, and 34% for older adults. Among URD HCT recipients, 5-year adjusted survival for the two time periods was 38% and 37% for children, 24% and 28% for AYAs, and 19% and 23% for older adults. Improvements in survival occurred because of a reduction in risk of treatment-related mortality. The risk of relapse did not change over time. Improvements in survival among AYAs undergoing allogeneic HCT for AML have paralleled those among children and older adults. Copyright © 2012 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Cross-Sectional Relationships of Physical Activity and Sedentary Behavior With Cognitive Function in Older Adults With Probable Mild Cognitive Impairment.

PubMed

Falck, Ryan S; Landry, Glenn J; Best, John R; Davis, Jennifer C; Chiu, Bryan K; Liu-Ambrose, Teresa

2017-10-01

Mild cognitive impairment (MCI) represents a transition between normal cognitive aging and dementia and may represent a critical time frame for promoting cognitive health through behavioral strategies. Current evidence suggests that physical activity (PA) and sedentary behavior are important for cognition. However, it is unclear whether there are differences in PA and sedentary behavior between people with probable MCI and people without MCI or whether the relationships of PA and sedentary behavior with cognitive function differ by MCI status. The aims of this study were to examine differences in PA and sedentary behavior between people with probable MCI and people without MCI and whether associations of PA and sedentary behavior with cognitive function differed by MCI status. This was a cross-sectional study. Physical activity and sedentary behavior in adults dwelling in the community (N = 151; at least 55 years old) were measured using a wrist-worn actigraphy unit. The Montreal Cognitive Assessment was used to categorize participants with probable MCI (scores of <26/30) and participants without MCI (scores of ≥26/30). Cognitive function was indexed using the Alzheimer Disease Assessment Scale-Cognitive-Plus (ADAS-Cog Plus). Physical activity and sedentary behavior were compared based on probable MCI status, and relationships of ADAS-Cog Plus with PA and sedentary behavior were examined by probable MCI status. Participants with probable MCI (n = 82) had lower PA and higher sedentary behavior than participants without MCI (n = 69). Higher PA and lower sedentary behavior were associated with better ADAS-Cog Plus performance in participants without MCI (β = -.022 and β = .012, respectively) but not in participants with probable MCI (β < .001 for both). This study was cross-sectional and therefore could not establish whether conversion to MCI attenuated the relationships of PA and sedentary behavior with cognitive function. The diagnosis of MCI was not confirmed

Possible benefit of consolidation therapy with high-dose cytarabine on overall survival of adults with non-promyelocytic acute myeloid leukemia.

PubMed

Azevedo, M C; Velloso, E D R P; Buccheri, V; Chamone, D A F; Dorlhiac-Llacer, P E

2015-02-01

In adults with non-promyelocytic acute myeloid leukemia (AML), high-dose cytarabine consolidation therapy has been shown to influence survival in selected patients, although the appropriate doses and schemes have not been defined. We evaluated survival after calculating the actual dose of cytarabine that patients received for consolidation therapy and divided them into 3 groups according to dose. We conducted a single-center, retrospective study involving 311 non-promyelocytic AML patients with a median age of 36 years (16-79 years) who received curative treatment between 1978 and 2007. The 131 patients who received cytarabine consolidation were assigned to study groups by their cytarabine dose protocol. Group 1 (n=69) received <1.5 g/m2 every 12 h on 3 alternate days for up to 4 cycles. The remaining patients received high-dose cytarabine (≥1.5 g/m2 every 12 h on 3 alternate days for up to 4 cycles). The actual dose received during the entire consolidation period in these patients was calculated, allowing us to divide these patients into 2 additional groups. Group 2 (n=27) received an intermediate-high-dose (<27 g/m2), and group 3 (n=35) received a very-high-dose (≥27 g/m2). Among the 311 patients receiving curative treatment, the 5-year survival rate was 20.2% (63 patients). The cytarabine consolidation dose was an independent determinant of survival in multivariate analysis; age, karyotype, induction protocol, French-American-British classification, and de novo leukemia were not. Comparisons showed that the risk of death was higher in the intermediate-high-dose group 2 (hazard ratio [HR]=4.51; 95% confidence interval [CI]: 1.81-11.21) and the low-dose group 1 (HR=4.43; 95% CI: 1.97-9.96) than in the very-high-dose group 3, with no significant difference between those two groups. Our findings indicated that very-high-dose cytarabine during consolidation in adults with non-promyelocytic AML may improve survival.

Possible benefit of consolidation therapy with high-dose cytarabine on overall survival of adults with non-promyelocytic acute myeloid leukemia

PubMed Central

Azevedo, M.C.; Velloso, E.D.R.P.; Buccheri, V.; Chamone, D.A.F.; Dorlhiac-Llacer, P.E.

2014-01-01

In adults with non-promyelocytic acute myeloid leukemia (AML), high-dose cytarabine consolidation therapy has been shown to influence survival in selected patients, although the appropriate doses and schemes have not been defined. We evaluated survival after calculating the actual dose of cytarabine that patients received for consolidation therapy and divided them into 3 groups according to dose. We conducted a single-center, retrospective study involving 311 non-promyelocytic AML patients with a median age of 36 years (16-79 years) who received curative treatment between 1978 and 2007. The 131 patients who received cytarabine consolidation were assigned to study groups by their cytarabine dose protocol. Group 1 (n=69) received <1.5 g/m2 every 12 h on 3 alternate days for up to 4 cycles. The remaining patients received high-dose cytarabine (≥1.5 g/m2 every 12 h on 3 alternate days for up to 4 cycles). The actual dose received during the entire consolidation period in these patients was calculated, allowing us to divide these patients into 2 additional groups. Group 2 (n=27) received an intermediate-high-dose (<27 g/m2), and group 3 (n=35) received a very-high-dose (≥27 g/m2). Among the 311 patients receiving curative treatment, the 5-year survival rate was 20.2% (63 patients). The cytarabine consolidation dose was an independent determinant of survival in multivariate analysis; age, karyotype, induction protocol, French-American-British classification, and de novo leukemia were not. Comparisons showed that the risk of death was higher in the intermediate-high-dose group 2 (hazard ratio [HR]=4.51; 95% confidence interval [CI]: 1.81-11.21) and the low-dose group 1 (HR=4.43; 95% CI: 1.97-9.96) than in the very-high-dose group 3, with no significant difference between those two groups. Our findings indicated that very-high-dose cytarabine during consolidation in adults with non-promyelocytic AML may improve survival. PMID:25517921

Causal inference in survival analysis using pseudo-observations.

PubMed

Andersen, Per K; Syriopoulou, Elisavet; Parner, Erik T

2017-07-30

Causal inference for non-censored response variables, such as binary or quantitative outcomes, is often based on either (1) direct standardization ('G-formula') or (2) inverse probability of treatment assignment weights ('propensity score'). To do causal inference in survival analysis, one needs to address right-censoring, and often, special techniques are required for that purpose. We will show how censoring can be dealt with 'once and for all' by means of so-called pseudo-observations when doing causal inference in survival analysis. The pseudo-observations can be used as a replacement of the outcomes without censoring when applying 'standard' causal inference methods, such as (1) or (2) earlier. We study this idea for estimating the average causal effect of a binary treatment on the survival probability, the restricted mean lifetime, and the cumulative incidence in a competing risks situation. The methods will be illustrated in a small simulation study and via a study of patients with acute myeloid leukemia who received either myeloablative or non-myeloablative conditioning before allogeneic hematopoetic cell transplantation. We will estimate the average causal effect of the conditioning regime on outcomes such as the 3-year overall survival probability and the 3-year risk of chronic graft-versus-host disease. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Attaching transmitters to waterbirds using one versus two subcutaneous anchors: Retention and survival trade-offs

USGS Publications Warehouse

Lewis, Tyler; Esler, Daniel N.; Uher-Koch, Brian D.; Dickson, Rian D.; Anderson, Eric M.; Evenson, Joseph R.; Hupp, Jerry W.; Flint, Paul L.

2017-01-01

A major challenge of wildlife telemetry is choosing an attachment technique that maximizes transmitter retention while minimizing negative side effects. For waterbirds, attachment of transmitters with subcutaneous anchors has been an effective and well-established technique, having been used on >40 species. This method was recently modified to include a second subcutaneous anchor, presumably increasing transmitter retention beyond that of single-anchor attachments. This putative benefit may be offset, however, by increased health risks related to additional incisions and subcutaneous protrusions. To test this potential trade-off, we attached radiotransmitters to molting and wintering surf (Melanitta perspicillata) and white-winged scoters (M. fusca) during 2008 and 2009 in Washington State and southeast Alaska, USA, using single- (121 scoters) and double-anchor (128 scoters) attachment techniques. We estimated daily probabilities of survival and radio retention for each group, this being apparent retention for wintering scoters because we could not differentiate shed transmitters from flighted emigration. For scoters during the flightless remigial molt, we found that addition of a second anchor increased cumulative retention probability (±SE) over a 49-day period from 0.69 ± 0.11 for single-anchor to 0.88 ± 0.07 for double-anchor attachments, while having no effect on survival. However, during winter, scoters with double-anchor attachments experienced no improvement in apparent retention, while having significantly lower survival during their first 14 days following transmitter attachment; of 15 mortalities during this period, 11 had 2 subcutaneous anchors. From day 15 onward, winter survival rates were nearly identical for single- versus double-anchor attachments, indicating that adverse effects of subcutaneous anchors were mainly limited to the 14-day postattachment period. Overall, given that the survival cost of adding a second subcutaneous anchor

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

Survival costs of chick rearing in black-legged kittiwakes

USGS Publications Warehouse

Golet, Gregory H.; Irons, David B.; Estes, James A.

1998-01-01

1. We tested for costs of chick rearing in the black-legged kittiwake Rissa tridactyla (Linnaeus) by removing entire clutches from 149 of 405 randomly selected nests, in which one or both mates was colour-banded. After the manipulation, we monitored adult nest attendance and body condition at unmanipulated and manipulated nests, and measured the survival and fecundity of these adults the following year.2. Late in the chick-rearing period, adults from unmanipulated nests (i.e. with chicks) went on significantly longer foraging trips, and were significantly lighter for their size, than adults from manipulated nests (i.e. without chicks).3. Adults from unmanipulated nests also survived to the following nesting season at a significantly lower rate than those from the manipulated nests (0·898 vs. 0·953), suggesting that attempting to raise chicks can reduce life expectancy by 55%.4. There was a tendency for adults from nests that were unmanipulated in year one to have lower reproductive success in year two, primarily because of reduced fledging success, and a higher incidence of non-breeding.5. These findings suggest that mass loss in kittiwakes during chick rearing may not be adaptive. Raising chicks can lead to reproductive costs, and the causal mechanism appears to be a reduction in body condition.6. We compare our results with previous brood (or clutch) size manipulation experiments that have measured adult body condition, survival and/or future fecundity. Although the empirical evidence suggests that long-lived species are more likely to experience survival costs than short-lived species, we believe the opposite may be true. We suggest that shifting the experimental protocol of cost of reproduction studies from brood enlargements (an approach taken in most prior studies) to brood reductions will provide more accurate quantifications of naturally occurring costs.7. The cost of reproduction is one mechanism proposed to explain the reduced survival rates reported

Survival estimates of wild and captive-bred released Puaiohi, an endangered Hawaiian thrush

USGS Publications Warehouse

VanderWerf, Eric; Crampton, Lisa H.; Diegmann, Julia; Atkinson, Carter T.; Leonard, David L.

2014-01-01

Estimating and monitoring adult and juvenile survival are vital to understanding population status, informing recovery planning for endangered species, and quantifying the success of management. We used mark–recapture models to estimate apparent annual survival of the Puaiohi (Myadestes palmeri), an endangered thrush endemic to the Hawaiian island of Kauai, from 2005 to 2011. Our sample included 87 wild birds and 123 captive-bred birds that were released at various ages. Survival was higher for wild adult males (0.71 ± 0.09) than for wild adult females (0.46 ± 0.12). Survival of wild juveniles (0.23 ± 0.06) was lower than that of wild adults of both sexes, indicating that recruitment may limit population growth. Captive-bred birds released when <1 yr old had survival (0.26 ± 0.21) comparable with that of wild juveniles, but captive-bred birds released at 1–3 yr old had very low survival (0.05 ± 0.06). Only 8 of 123 (7%) captive birds were seen again after release. Two wild birds resighted five years after marking are the oldest known individuals, being at least six years of age. Malarial infection did not affect survival of wild Puaiohi, unlike many Hawaiian forest birds. The difference between adult male and adult female survival is consistent with rat (Rattusspp.) predation of females on the nest as a major source of mortality. As such, attempting to reduce nest predation by controlling rats may be the best available management option. Releasing captive-bred birds has had little effect on the wild population in recent years.

The impact of household wealth on child survival in Ghana.

PubMed

Lartey, Stella T; Khanam, Rasheda; Takahashi, Shingo

2016-11-22

Improving child health is one of the major policy agendas for most of the governments, especially in the developing countries. These governments have been implementing various strategies such as improving healthcare financing, improving access to health, increasing educational level, and income level of the household to improve child health. Despite all these efforts, under-five and infant mortality rates remain high in many developing nations. Some previous studies examined how economic development or household's economic condition contributes to child survival in developing countries. In Ghana, the question as to what extent does economic circumstances of households reduces infant and child mortality still remain largely unanswered. Thus, the purpose of this study is to investigate the extent to which wealth affects the survival of under-five children, using data from the Demographic and Health Survey (DHS) of Ghana. In this study, we use four waves of data from Demographic and Health Surveys (DHS) of Ghana from 1993 to 2008. The DHS is a detailed data set that provides comprehensive information on households and their demographic characteristics in Ghana. Data was obtained by distributing questionnaires to women (from 6000 households) of reproductive age between 15 and 49 years, which asked, among other things, their birth history information. The Weibull hazard model with gamma frailty was used to estimate wealth effect, as well as the trend of wealth effect on child's survival probability. We find that household wealth status has a significant effect on the child survival in Ghana. A child is more likely to survive when he/she is from a household with high wealth status. Among other factors, birth spacing and parental education were found to be highly significant to increase a child's survival probability. Our findings offer plausible mechanisms for the association of household wealth and child survival. We therefore suggest that the Government of Ghana

Survival among older adults with kidney failure is better in the first three years with chronic dialysis treatment than not.

PubMed

Tam-Tham, Helen; Quinn, Robert R; Weaver, Robert G; Zhang, Jianguo; Ravani, Pietro; Liu, Ping; Thomas, Chandra; King-Shier, Kathryn; Fruetel, Karen; James, Matt T; Manns, Braden J; Tonelli, Marcello; Murtagh, Fliss E M; Hemmelgarn, Brenda R

2018-05-23

Comparisons of survival between dialysis and nondialysis care for older adults with kidney failure have been limited to those managed by nephrologists, and are vulnerable to lead and immortal time biases. So we compared time to all-cause mortality among older adults with kidney failure treated vs. not treated with chronic dialysis. Our retrospective cohort study used linked administrative and laboratory data to identify adults aged 65 or more years of age in Alberta, Canada, with kidney failure (2002-2012), defined by two or more consecutive outpatient estimated glomerular filtration rates less than 10 mL/min/1.73m 2 , spanning 90 or more days. We used marginal structural Cox models to assess the association between receipt of dialysis and all-cause mortality by allowing control for both time-varying and baseline confounders. Overall, 838 patients met inclusion criteria (mean age 79.1; 48.6% male; mean estimated glomerular filtration rate 7.8 mL/min/1.73m 2 ). Dialysis treatment (vs. no dialysis) was associated with a significantly lower risk of death for the first three years of follow-up (hazard ratio 0.59 [95% confidence interval 0.46-0.77]), but not thereafter (1.22 [0.69-2.17]). However, dialysis was associated with a significantly higher risk of hospitalization (1.40 [1.16-1.69]). Thus, among older adults with kidney failure, treatment with dialysis was associated with longer survival up to three years after reaching kidney failure, though with a higher risk of hospital admissions. These findings may assist shared decision-making about treatment of kidney failure. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

Increasing mortality burden among adults with complex congenital heart disease.

PubMed

Greutmann, Matthias; Tobler, Daniel; Kovacs, Adrienne H; Greutmann-Yantiri, Mehtap; Haile, Sarah R; Held, Leonhard; Ivanov, Joan; Williams, William G; Oechslin, Erwin N; Silversides, Candice K; Colman, Jack M

2015-01-01

Progress in management of congenital heart disease has shifted mortality largely to adulthood. However, adult survivors with complex congenital heart disease are not cured and remain at risk of premature death as young adults. Thus, our aim was to describe the evolution and mortality risk of adult patient cohorts with complex congenital heart disease. Among 12,644 adults with congenital heart disease followed at a single center from 1980 to 2009, 176 had Eisenmenger syndrome, 76 had unrepaired cyanotic defects, 221 had atrial switch operations for transposition of the great arteries, 158 had congenitally corrected transposition of the great arteries, 227 had Fontan palliation, and 789 had repaired tetralogy of Fallot. We depict the 30-year evolution of these 6 patient cohorts, analyze survival probabilities in adulthood, and predict future number of deaths through 2029. Since 1980, there has been a steady increase in numbers of patients followed, except in cohorts with Eisenmenger syndrome and unrepaired cyanotic defects. Between 1980 and 2009, 308 patients in the study cohorts (19%) died. At the end of 2009, 85% of survivors were younger than 50 years. Survival estimates for all cohorts were markedly lower than for the general population, with important differences between cohorts. Over the upcoming two decades, we predict a substantial increase in numbers of deaths among young adults with subaortic right ventricles, Fontan palliation, and repaired tetralogy of Fallot. Anticipatory action is needed to prepare clinical services for increasing numbers of young adults at risk of dying from complex congenital heart disease. © 2014 The Authors. Congenital Heart Disease Published by Wiley Periodicals, Inc.

Survival and selected outcomes of older adults with locally advanced head/neck cancer treated with chemoradiation therapy.

PubMed

Maggiore, Ronald J; Curran, Emily K; Witt, Mary Ellyn; Haraf, Daniel J; Vokes, Everett E; Cohen, Ezra E W

2013-10-01

Chemoradiation therapy (CRT) remains a potentially curative treatment in patients with locally advanced head/neck cancer (LA-HNC). However, survival and other outcomes in older patients with head/neck cancer receiving chemoradiotherapy are not well established. This study was performed to elucidate selected outcomes in this patient population. Retrospective study of LA-HNC patients ≥ 70 years of age who had received 5-fluorouracil-hydoxyurea-based CRT with a minimum of 3 years of follow up after therapy initiation was performed. Pre-treatment patient- and cancer-related characteristics were recorded. Survival data in addition to gastrostomy tube utilization, swallowing function, and hematologic toxicity were captured. Eighty-nine patients treated between 1997 and 2009 were eligible for analysis (median age, 76 years; range, 70-94; male, 61%; ECOG PS, 0-1 43%; stage IVA/B, 71%). 86 were evaluable for survival analysis. 5-year overall and event-free survival were both at 32% with a median follow-up time of 39.2 months. The majority (86.5%) were able to complete all planned treatment cycles. A significant proportion of patients, however, required gastrostomy tube during CRT (62%) and developed aspiration during swallowing evaluation post-treatment (44%). Several patients required hospice (9%) or skilled nursing facility (13%) referrals during treatment. Select older adults with LA-HNC can still experience long-term benefits despite 5-year survival rates lower than those historically reported in younger patients undergoing identical CRT regimens although potentially at higher risk for acute toxicities. Assessment and selection of those who can tolerate more intense combined-modality strategies and their long-term outcomes merit further larger, prospective studies. Copyright © 2013 Elsevier Inc. All rights reserved.

Swift fox survival and production in southeastern Wyoming

USGS Publications Warehouse

Olson, Travis L.; Lindzey, Frederick 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.

Direct transport to a PCI-capable hospital is associated with improved survival after adult out-of-hospital cardiac arrest of medical aetiology.

PubMed

McKenzie, Nicole; Williams, Teresa A; Ho, Kwok M; Inoue, Madoka; Bailey, Paul; Celenza, Antonio; Fatovich, Daniel; Jenkins, Ian; Finn, Judith

2018-05-02

To compare survival outcomes of adults with out-of-hospital cardiac arrest (OHCA) of medical aetiology directly transported to a percutaneous-coronary-intervention capable (PCI-capable) hospital (direct transport) with patients transferred to a PCI-capable hospital via another hospital without PCI services available (indirect transport) by emergency medical services (EMS). This retrospective cohort study used the St John Ambulance Western Australia OHCA Database and medical chart review. We included OHCA patients (≥18 years) admitted to any one of five PCI-capable hospitals in Perth between January 2012 and December 2015. Survival to hospital discharge (STHD) and survival up to 12-months after OHCA were compared between the direct and indirect transport groups using multivariable logistic and Cox-proportional hazards regression, respectively, while adjusting for so-called "Utstein variables" and other potential confounders. Of the 509 included patients, 404 (79.4%) were directly transported to a PCI-capable hospital and 105 (20.6%) transferred via another hospital to a PCI-capable hospital; 274/509 (53.8%) patients STHD and 253/509 (49.7%) survived to 12-months after OHCA. Direct transport patients were twice as likely to STHD (adjusted odds ratio 1.97, 95% confidence interval [CI] 1.13-3.43) than those transferred via another hospital. Indirect transport was also associated with a possible increased risk of death, up to 12-months, compared to direct transport (adjusted hazard ratio 1.36, 95% CI 1.00-1.84). Direct transport to a PCI-capable hospital for post-resuscitation care is associated with a survival advantage for adults with OHCA of medical aetiology. This has implications for EMS transport protocols for patients with OHCA. Copyright © 2018 Elsevier B.V. All rights reserved.

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.

Risk of revision surgery for adult idiopathic scoliosis: a survival analysis of 517 cases over 25 years.

PubMed

Riouallon, Guillaume; Bouyer, Benjamin; Wolff, Stéphane

2016-08-01

Little is known about the long-term status of patients operated for spine deformities. The aim of this study was to determine the survival of primary fusion in adult idiopathic scoliosis and identify the risk factors of revision surgery. Adult patients who underwent primary fusion for idiopathic scoliosis between 1983 and 2011 were included in a continuous monocentric retrospective series. Any additional surgery was registered for survival analysis. Survival and follow-up were estimated by the Kaplan-Meier method and an analysis was performed to identify the risk factors of revision surgery. This series included 447 women (86.5 %) and 70 men (13.5 %) reviewed after a mean follow-up of 7 years (range 0-26.4). Mean age was 44.4 years. Fusion was performed on a median 11 levels (range 3-15); revision rate was 13 % (CI 10-17), 18 % (CI 14-23) and 20 % (CI 16-26) at 5, 10 and 15 years, respectively. Revision surgery was associated with age, anterior release, length of fusion, the inferior limit of fusion, post-operative sagittal balance and junctional kyphosis. The length of fusion (HR 1.13 per vertebrae fused, p = 0.007) and the lower limit of fusion (HR 5.9, p < 0.001) remained independent predictors of revision surgery on multivariate analysis. This series evaluated the risk of revision surgery following spinal fusion for idiopathic scoliosis. Our results show that the risk seemed to increase linearly with a rate of nearly 20 % after 10 years. The length and lower limit of fusion are the main risk factors for revision surgery. Level IV (e.g. case series).

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

PubMed Central

Pan, Yongliang; Liu, Yan; Lieberwirth, Claudia; Zhang, Zhibin; Wang, Zuoxin

2016-01-01

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 (M. 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

A Population-Based Observational Study of First-Course Treatment and Survival for Adolescent and Young Adult Females with Breast Cancer

PubMed Central

DeRouen, Mindy C.; Gomez, Scarlett L.; Press, David J.; Tao, Li; Kurian, Allison W.

2013-01-01

Purpose Young age at breast cancer diagnosis is associated with poor survival. However, little is known about factors associated with first-course treatment receipt or survival among adolescent and young adult (AYA) females aged 15–39 years. Methods Data regarding 19,906 eligible AYA breast cancers diagnosed in California during 1992–2009 were obtained from the population-based California Cancer Registry. Multivariable logistic regression was used to evaluate clinical and sociodemographic differences in treatment receipt. Multivariable Cox proportional hazards regression was used to examine differences in survival by initial treatment, and by patient and tumor characteristics. Results Black and Hispanic AYAs diagnosed with in situ or stages I–III breast cancer were more likely than White AYAs to receive breast-conserving surgery (BCS) without radiation; Asian and Hispanic AYAs were more likely than Whites to receive mastectomy. Women in lower socioeconomic status (SES) neighborhoods were more likely to omit radiation after BCS, more likely to receive mastectomy, and less likely to receive chemotherapy, compared to those in higher SES neighborhoods. Among patients with invasive disease, survival improved an average of 5% per year during 1992–2009. AYAs who received BCS with radiation experienced better survival than other surgery/radiation options. Black AYAs had poorer survival than Whites. AYAs who resided in higher SES neighborhoods had better survival. Conclusions Treatment receipt among AYAs with breast cancer varied by race/ethnicity and neighborhood SES. Poor survival for Black AYAs and AYAs living in low SES neighborhoods in models adjusted for treatment receipt suggests that factors other than treatment may also be important to disease outcome. PMID:24066271

Coyote removal, understory cover, and survival of white-tailed deer neonates: Coyote Control and Fawn Survival

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kilgo, John C.; Vukovich, Mark; Ray, H. Scott

Predation by coyotes (Canis latrans) on white-tailed deer (Odocoileus virginianus) neonates has led to reduced recruitment in many deer populations in southeastern North America. This low recruitment combined with liberal antlerless deer harvest has resulted in declines in some deer populations, and consequently, increased interest in coyote population control. We investigated whether neonate survival increased after coyote removal, whether coyote predation on neonates was additive to other mortality sources, and whether understory vegetation density affected neonate survival. We monitored neonate survival for 4 years prior to (2006–2009) and 3 years during (2010–2012) intensive coyote removal on 3 32-km 2 unitsmore » on the United States Department of Energy’s Savannah River Site, South Carolina. We removed 474 coyotes (1.63 coyotes/km 2 per unit per year), reducing coyote abundance by 78% from pre-removal levels. The best model (w i = 0.927) describing survival probability among 216 radio-collared neonates included a within-year quadratic time trend variable, date of birth, removal treatment, and a varying removal year effect. Under this model, survival differed between pre-treatment and removal periods and it differed among years during the removal period, being >100% greater than pre-treatment survival (0.228) during the first removal year (0.513), similar to pre-treatment survival during the second removal year (0.202), and intermediate during the third removal year (0.431). Despite an initial increase, the overall effect of coyote removal on neonate survival was modest. Mortality rate attributable to coyote predation was lowest during the first removal year (0.357) when survival was greatest, but the mortality rate from all other causes did not differ between the pretreatment period and any year during removals, indicating that coyote predation acted as an additive source of mortality. Survival probability was not related to vegetation cover, either

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 R.; 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

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

Adjusting survival estimates for premature transmitter failure: A case study from the Sacramento-San Joaquin Delta

USGS Publications Warehouse

Holbrook, Christopher M.; Perry, Russell W.; Brandes, Patricia L.; Adams, Noah S.

2013-01-01

In telemetry studies, premature tag failure causes negative bias in fish survival estimates because tag failure is interpreted as fish mortality. We used mark-recapture modeling to adjust estimates of fish survival for a previous study where premature tag failure was documented. High rates of tag failure occurred during the Vernalis Adaptive Management Plan’s (VAMP) 2008 study to estimate survival of fall-run Chinook salmon (Oncorhynchus tshawytscha) during migration through the San Joaquin River and Sacramento-San Joaquin Delta, California. Due to a high rate of tag failure, the observed travel time distribution was likely negatively biased, resulting in an underestimate of tag survival probability in this study. Consequently, the bias-adjustment method resulted in only a small increase in estimated fish survival when the observed travel time distribution was used to estimate the probability of tag survival. Since the bias-adjustment failed to remove bias, we used historical travel time data and conducted a sensitivity analysis to examine how fish survival might have varied across a range of tag survival probabilities. Our analysis suggested that fish survival estimates were low (95% confidence bounds range from 0.052 to 0.227) over a wide range of plausible tag survival probabilities (0.48–1.00), and this finding is consistent with other studies in this system. When tags fail at a high rate, available methods to adjust for the bias may perform poorly. Our example highlights the importance of evaluating the tag life assumption during survival studies, and presents a simple framework for evaluating adjusted survival estimates when auxiliary travel time data are available.

High expression of ID family and IGJ genes signature as predictor of low induction treatment response and worst survival in adult Hispanic patients with B-acute lymphoblastic leukemia.

PubMed

Cruz-Rodriguez, Nataly; Combita, Alba L; Enciso, Leonardo J; Quijano, Sandra M; Pinzon, Paula L; Lozano, Olga C; Castillo, Juan S; Li, Li; Bareño, Jose; Cardozo, Claudia; Solano, Julio; Herrera, Maria V; Cudris, Jennifer; Zabaleta, Jovanny

2016-04-05

B-Acute lymphoblastic leukemia (B-ALL) represents a hematologic malignancy with poor clinical outcome and low survival rates in adult patients. Remission rates in Hispanic population are almost 30% lower and Overall Survival (OS) nearly two years inferior than those reported in other ethnic groups. Only 61% of Colombian adult patients with ALL achieve complete remission (CR), median overall survival is 11.3 months and event-free survival (EFS) is 7.34 months. Identification of prognostic factors is crucial for the application of proper treatment strategies and subsequently for successful outcome. Our goal was to identify a gene expression signature that might correlate with response to therapy and evaluate the utility of these as prognostic tool in hispanic patients. We included 43 adult patients newly diagnosed with B-ALL. We used microarray analysis in order to identify genes that distinguish poor from good response to treatment using differential gene expression analysis. The expression profile was validated by real-time PCR (RT-PCT). We identified 442 differentially expressed genes between responders and non-responders to induction treatment. Hierarchical analysis according to the expression of a 7-gene signature revealed 2 subsets of patients that differed in their clinical characteristics and outcome. Our study suggests that response to induction treatment and clinical outcome of Hispanic patients can be predicted from the onset of the disease and that gene expression profiles can be used to stratify patient risk adequately and accurately. The present study represents the first that shows the gene expression profiling of B-ALL Colombian adults and its relevance for stratification in the early course of disease.

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.

Epidemiology of Undiagnosed Trichomoniasis in a Probability Sample of Urban Young Adults

PubMed Central

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

Attitudes toward Bisexual Men and Women among a Nationally Representative Probability Sample of Adults in the United States

PubMed Central

Herbenick, Debby; Friedman, M. Reuel; Schick, Vanessa; Fu, Tsung-Chieh (Jane); Bostwick, Wendy; Bartelt, Elizabeth; Muñoz-Laboy, Miguel; Pletta, David; Reece, Michael; Sandfort, Theo G. M.

2016-01-01

As bisexual individuals in the United States (U.S.) face significant health disparities, researchers have posited that these differences may be fueled, at least in part, by negative attitudes, prejudice, stigma, and discrimination toward bisexual individuals from heterosexual and gay/lesbian individuals. Previous studies of individual and social attitudes toward bisexual men and women have been conducted almost exclusively with convenience samples, with limited generalizability to the broader U.S. population. Our study provides an assessment of attitudes toward bisexual men and women among a nationally representative probability sample of heterosexual, gay, lesbian, and other-identified adults in the U.S. Data were collected from the 2015 National Survey of Sexual Health and Behavior (NSSHB), via an online questionnaire with a probability sample of adults (18 years and over) from throughout the U.S. We included two modified 5-item versions of the Bisexualities: Indiana Attitudes Scale (BIAS), validated sub-scales that were developed to measure attitudes toward bisexual men and women. Data were analyzed using descriptive statistics, gamma regression, and paired t-tests. Gender, sexual identity, age, race/ethnicity, income, and educational attainment were all significantly associated with participants' attitudes toward bisexual individuals. In terms of responses to individual scale items, participants were most likely to “neither agree nor disagree” with all attitudinal statements. Across sexual identities, self-identified other participants reported the most positive attitudes, while heterosexual male participants reported the least positive attitudes. As in previous research on convenience samples, we found a wide range of demographic characteristics were related with attitudes toward bisexual individuals in our nationally-representative study of heterosexual, gay/lesbian, and other-identified adults in the U.S. In particular, gender emerged as a significant

The Probability Heuristics Model of Syllogistic Reasoning.

ERIC Educational Resources Information Center

Chater, Nick; Oaksford, Mike

1999-01-01

Proposes a probability heuristic model for syllogistic reasoning and confirms the rationality of this heuristic by an analysis of the probabilistic validity of syllogistic reasoning that treats logical inference as a limiting case of probabilistic inference. Meta-analysis and two experiments involving 40 adult participants and using generalized…

Sexual diversity in the United States: Results from a nationally representative probability sample of adult women and men.

PubMed

Herbenick, Debby; Bowling, Jessamyn; Fu, Tsung-Chieh Jane; Dodge, Brian; Guerra-Reyes, Lucia; Sanders, Stephanie

2017-01-01

In 2015, we conducted a cross-sectional, Internet-based, U.S. nationally representative probability survey of 2,021 adults (975 men, 1,046 women) focused on a broad range of sexual behaviors. Individuals invited to participate were from the GfK KnowledgePanel®. The survey was titled the 2015 Sexual Exploration in America Study and survey completion took about 12 to 15 minutes. The survey was confidential and the researchers never had access to respondents' identifiers. Respondents reported on demographic items, lifetime and recent sexual behaviors, and the appeal of 50+ sexual behaviors. Most (>80%) reported lifetime masturbation, vaginal sex, and oral sex. Lifetime anal sex was reported by 43% of men (insertive) and 37% of women (receptive). Common lifetime sexual behaviors included wearing sexy lingerie/underwear (75% women, 26% men), sending/receiving digital nude/semi-nude photos (54% women, 65% men), reading erotic stories (57% of participants), public sex (≥43%), role-playing (≥22%), tying/being tied up (≥20%), spanking (≥30%), and watching sexually explicit videos/DVDs (60% women, 82% men). Having engaged in threesomes (10% women, 18% men) and playful whipping (≥13%) were less common. Lifetime group sex, sex parties, taking a sexuality class/workshop, and going to BDSM parties were uncommon (each <8%). More Americans identified behaviors as "appealing" than had engaged in them. Romantic/affectionate behaviors were among those most commonly identified as appealing for both men and women. The appeal of particular behaviors was associated with greater odds that the individual had ever engaged in the behavior. This study contributes to our understanding of more diverse adult sexual behaviors than has previously been captured in U.S. nationally representative probability surveys. Implications for sexuality educators, clinicians, and individuals in the general population are discussed.

Sexual diversity in the United States: Results from a nationally representative probability sample of adult women and men

PubMed Central

Herbenick, Debby; Bowling, Jessamyn; Fu, Tsung-Chieh (Jane); Guerra-Reyes, Lucia; Sanders, Stephanie

2017-01-01

In 2015, we conducted a cross-sectional, Internet-based, U.S. nationally representative probability survey of 2,021 adults (975 men, 1,046 women) focused on a broad range of sexual behaviors. Individuals invited to participate were from the GfK KnowledgePanel®. The survey was titled the 2015 Sexual Exploration in America Study and survey completion took about 12 to 15 minutes. The survey was confidential and the researchers never had access to respondents’ identifiers. Respondents reported on demographic items, lifetime and recent sexual behaviors, and the appeal of 50+ sexual behaviors. Most (>80%) reported lifetime masturbation, vaginal sex, and oral sex. Lifetime anal sex was reported by 43% of men (insertive) and 37% of women (receptive). Common lifetime sexual behaviors included wearing sexy lingerie/underwear (75% women, 26% men), sending/receiving digital nude/semi-nude photos (54% women, 65% men), reading erotic stories (57% of participants), public sex (≥43%), role-playing (≥22%), tying/being tied up (≥20%), spanking (≥30%), and watching sexually explicit videos/DVDs (60% women, 82% men). Having engaged in threesomes (10% women, 18% men) and playful whipping (≥13%) were less common. Lifetime group sex, sex parties, taking a sexuality class/workshop, and going to BDSM parties were uncommon (each <8%). More Americans identified behaviors as “appealing” than had engaged in them. Romantic/affectionate behaviors were among those most commonly identified as appealing for both men and women. The appeal of particular behaviors was associated with greater odds that the individual had ever engaged in the behavior. This study contributes to our understanding of more diverse adult sexual behaviors than has previously been captured in U.S. nationally representative probability surveys. Implications for sexuality educators, clinicians, and individuals in the general population are discussed. PMID:28727762

Differential survival among sSOD-1* genotypes in Chinook Salmon

USGS Publications Warehouse

Hayes, Michael C.; Reisenbichler, Reginald R.; Rubin, Stephen P.; Wetzel, Lisa A.; Marshall , Anne R.

2011-01-01

Differential survival and growth were tested in Chinook salmon Oncorhynchus tshawytscha expressing two common alleles, *–100 and *–260, at the superoxide dismutase locus (sSOD-1*). These tests were necessary to support separate studies in which the two alleles were used as genetic marks under the assumption of mark neutrality. Heterozygous adults were used to produce progeny with –100/–100, –100/–260, and –260/–260 genotypes that were reared in two natural streams and two hatcheries in the states of Washington and Oregon. The latter also were evaluated as returning adults. In general, the genotype ratios of juveniles reared at hatcheries were consistent with high survival and little or no differential survival in the hatchery. Adult returns at one hatchery were significantly different from the expected proportions, and the survival of the –260/–260 genotype was 0.56–0.89 times that of the –100/–100 genotype over four year-classes. Adult returns at a second hatchery (one year-class) were similar but not statistically significant: survival of the –260/–260genotype relative to the –100/–100 genotype was 0.76. The performance of the heterozygote group was intermediate at both hatcheries. Significant differences in growth were rarely observed among hatchery fish (one year-class of juveniles and one age-class of adult males) but were consistent with greater performance for the –100/–100 genotype. Results from two groups of juveniles reared in streams (one year-class from each stream) suggested few differences in growth, but the observed genotype ratios were significantly different from the expected ratios in one stream. Those differences were consistent with the adult data; survival for the –260/–260 genotype was 76% of that of the –100/–100 genotype. These results, which indicate nonneutrality among sSOD-1* genotypes, caused us to modify our related studies and suggest caution in the interpretation of results and analyses in

Survival after acute hemodialysis in Pennsylvania, 2005-2007: a retrospective cohort study.

PubMed

Ramer, Sarah J; Cohen, Elan D; Chang, Chung-Chou H; Unruh, Mark L; Barnato, Amber E

2014-01-01

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. 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. 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). 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.

Cougar survival and source-sink structure on Greater Yellowstone's Northern Range

USGS Publications Warehouse

Ruth, T.K.; Haroldson, M.A.; Murphy, K.M.; Buotte, P.C.; Hornocker, M.G.; Quigley, H.B.

2011-01-01

We studied survival and causes of mortality of radiocollared cougars (Puma concolor) on the Greater Yellowstone Northern Range (GYNR) prior to (1987–1994) and after wolf (Canis lupus) reintroduction (1998–2005) and evaluated temporal, spatial, and environmental factors that explain variation in adult, subadult, and kitten survival. Using Program MARK and multimodel inference, we modeled cougar survival based on demographic status, season, and landscape attributes. Our best models for adult and independent subadults indicated that females survived better than males and survival increased with age until cougars reached older ages. Lower elevations and increasing density of roads, particularly in areas open to cougar hunting north of Yellowstone National Park (YNP), increased mortality risks for cougars on the GYNR. Indices of ungulate biomass, cougar and wolf population size, winter severity, rainfall, and individual characteristics such as the presence of dependent young, age class, and use of Park or Wilderness were not important predictors of survival. Kitten survival increased with age, was lower during winter, increased with increasing minimum estimates of elk calf biomass, and increased with increasing density of adult male cougars. Using our best model, we mapped adult cougar survival on the GYNR landscape. Results of receiver operating characteristic (ROC) analysis indicated a good model fit for both female (area under the curve [AUC] = 0.81, 95%CI = 0.70–0.92, n = 35 locations) and male cougars (AUC = 0.84, 95%CI = 0.74–0.94, n = 49 locations) relative to hunter harvest locations in our study area. Using minimum estimates of survival necessary to sustain the study population, we developed a source-sink surface and we identify several measures that resource management agencies can take to enhance cougar population management based on a source-sink strategy.

Genetic Architecture of Natural Variation Underlying Adult Foraging Behavior That Is Essential for Survival of Drosophila melanogaster.

PubMed

Lee, Yuh Chwen G; Yang, Qian; Chi, Wanhao; Turkson, Susie A; Du, Wei A; Kemkemer, Claus; Zeng, Zhao-Bang; Long, Manyuan; Zhuang, Xiaoxi

2017-05-01

Foraging behavior is critical for the fitness of individuals. However, the genetic basis of variation in foraging behavior and the evolutionary forces underlying such natural variation have rarely been investigated. We developed a systematic approach to assay the variation in survival rate in a foraging environment for adult flies derived from a wild Drosophila melanogaster population. Despite being such an essential trait, there is substantial variation of foraging behavior among D. melanogaster strains. Importantly, we provided the first evaluation of the potential caveats of using inbred Drosophila strains to perform genome-wide association studies on life-history traits, and concluded that inbreeding depression is unlikely a major contributor for the observed large variation in adult foraging behavior. We found that adult foraging behavior has a strong genetic component and, unlike larval foraging behavior, depends on multiple loci. Identified candidate genes are enriched in those with high expression in adult heads and, demonstrated by expression knock down assay, are involved in maintaining normal functions of the nervous system. Our study not only identified candidate genes for foraging behavior that is relevant to individual fitness, but also shed light on the initial stage underlying the evolution of the behavior. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

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.

A historical estimate of apparent survival of American oystercatcher (Haematopus palliatus) in Virginia

USGS Publications Warehouse

Nol, Erica; Murphy, Sean P.; Cadman, Michael D.

2012-01-01

Using mark-recapture models, apparent survival was estimated from older banding and re-sighting data (1978–1983) of American Oystercatchers (Haematopus palliatus) nesting on beaches and in salt marshes of coastal Virginia, USA. Oystercatchers nesting in salt marshes exhibited higher apparent survival (0.94 ±0.03) than birds nesting on beaches (0.81 ±0.06), a difference due to variation in mortality, permanent emigration, or both. Nesting on exposed barrier beaches may subject adults and young to higher risk of predation. These early estimates of adult survival for a species that is heavily monitored along the Atlantic and Gulf Coasts can be used to (1) develop demographic models to determine population stability, (2) compare with estimates of adult survival from populations that have reached carrying capacity, and (3) compare with estimates of survival from other oystercatcher populations and species.

Data-Driven Lead-Acid Battery Prognostics Using Random Survival Forests

DTIC Science & Technology

2014-10-02

Kogalur, Blackstone , & Lauer, 2008; Ishwaran & Kogalur, 2010). Random survival forest is a sur- vival analysis extension of Random Forests (Breiman, 2001...Statistics & probability letters, 80(13), 1056–1064. Ishwaran, H., Kogalur, U. B., Blackstone , E. H., & Lauer, M. S. (2008). Random survival forests. The

[Reduced survival and infestation of coffee borer, Hypothenemus hampei (Ferrari) (Coleoptera: Scolytidae), on coffee fruits, in response to neem sprays in laboratory].

PubMed

Depieri, Rogério A; Martinez, Sueli S

2010-01-01

Aqueous solutions of neem oil and aqueous extracts of neem seeds and leaves were sprayed on coffee fruits for laboratory evaluation of their efficiency in reducing infestation of the coffee borer, Hypothenemus hampei (Ferrari), in multi-choice preference assays in laboratory. Neem oil and extracts reduced infestation of fruits in a dose-dependent manner, acting as a repellent. At 0.5%, 1% and 1.5%, the oil reduced fruit infestation by 30.2%, 42.5% (P > 0.05), and 58.6% (P < 0.05), respectively, as compared with the control. Seed extracts at 1%, 2% and 4% (w/v) reduced infestation by 30.9%, 38.3% (P > 0.05) and 70.2% (P < 0.05), respectively; seed extracts at 0.15%, 1.5% and 15% (w/v) reduced fruit infestation by 16.5%, 38.5% (P > 0.05) and 56.9% (P < 0.05), respectively. Spraying the emulsifiable oil at 1% on coffee fruits and adult borers was compared with spraying on fruits or adults only. Adult-only spraying caused low mortality (P > 0.05) and low reduction on the number of damaged fruits (P > 0.05). Fruit-only spraying significantly reduced insect survival rates and the number of damaged fruits (P < 0.05). However, spraying on adults and fruits caused the greatest reduction in adult survival (55.6%; P < 0.05) and in fruit infestation (78.7%; P < 0.05), probably due to insect mortality and neem oil repellence acting together.

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

Access to kidney transplantation in European adults aged 75-84 years and related outcomes: an analysis of the European Renal Association-European Dialysis and Transplant Association Registry.

PubMed

Pippias, Maria; Stel, Vianda S; Kramer, Anneke; Abad Diez, Jose M; Aresté-Fosalba, Nuria; Ayav, Carole; Buturovic, Jadranka; Caskey, Fergus J; Collart, Frederic; Couchoud, Cécile; De Meester, Johan; Heaf, James G; Helanterä, Ilkka; Hemmelder, Marc H; Kostopoulou, Myrto; Noordzij, Marlies; Pascual, Julio; Palsson, Runolfur; Reisaeter, Anna Varberg; Traynor, Jamie P; Massy, Ziad; Jager, Kitty J

2018-05-01

To what extent access to, and allocation of kidney transplants and survival outcomes in patients aged ≥75 years have changed over time in Europe is unclear. We included patients aged ≥75-84 years (termed older adults) receiving renal replacement therapy in thirteen European countries between 2005 and 2014. Country differences and time trends in access to, and allocation of kidney transplants were examined. Survival outcomes were determined by Cox regression analyses. Between 2005 and 2014, 1392 older adult patients received 1406 transplants. Access to kidney transplantation varied from ~0% (Slovenia, Greece and Denmark) to ~4% (Norway and various Spanish regions) of all older adult dialysis patients, and overall increased from 0.3% (2005) to 0.9% (2014). Allocation of kidney transplants to older adults overall increased from 0.8% (2005) to 3.2% (2014). Seven-year unadjusted patient and graft survival probabilities were 49.1% (95% confidence interval, 95% CI: 43.6; 54.4) and 41.7% (95% CI: 36.5; 46.8), respectively, with a temporal trend towards improved survival outcomes. In conclusion, in the European dialysis population aged ≥75-84 years access to kidney transplantation is low, and allocation of kidney transplants remains a rare event. Though both are increasing with time and vary considerably between countries. The trend towards improved survival outcomes is encouraging. This information can aid informed decision-making regarding treatment options. © 2018 Steunstichting ESOT.

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.

Small-Scale Spatio-Temporal Distribution of Bactrocera minax (Enderlein) (Diptera: Tephritidae) Using Probability Kriging.

PubMed

Wang, S Q; Zhang, H Y; Li, Z L

2016-10-01

Understanding spatio-temporal distribution of pest in orchards can provide important information that could be used to design monitoring schemes and establish better means for pest control. In this study, the spatial and temporal distribution of Bactrocera minax (Enderlein) (Diptera: Tephritidae) was assessed, and activity trends were evaluated by using probability kriging. Adults of B. minax were captured in two successive occurrences in a small-scale citrus orchard by using food bait traps, which were placed both inside and outside the orchard. The weekly spatial distribution of B. minax within the orchard and adjacent woods was examined using semivariogram parameters. The edge concentration was discovered during the most weeks in adult occurrence, and the population of the adults aggregated with high probability within a less-than-100-m-wide band on both of the sides of the orchard and the woods. The sequential probability kriged maps showed that the adults were estimated in the marginal zone with higher probability, especially in the early and peak stages. The feeding, ovipositing, and mating behaviors of B. minax are possible explanations for these spatio-temporal patterns. Therefore, spatial arrangement and distance to the forest edge of traps or spraying spot should be considered to enhance pest control on B. minax in small-scale orchards.

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

Density-dependent intraspecific aggression regulates survival in northern Yellowstone wolves (Canis lupus).

PubMed

Cubaynes, Sarah; MacNulty, Daniel R; Stahler, Daniel R; Quimby, Kira A; Smith, Douglas W; Coulson, Tim

2014-11-01

Understanding the population dynamics of top-predators is essential to assess their impact on ecosystems and to guide their management. Key to this understanding is identifying the mechanisms regulating vital rates. Determining the influence of density on survival is necessary to understand the extent to which human-caused mortality is compensatory or additive. In wolves (Canis lupus), empirical evidence for density-dependent survival is lacking. Dispersal is considered the principal way in which wolves adjust their numbers to prey supply or compensate for human exploitation. However, studies to date have primarily focused on exploited wolf populations, in which density-dependent mechanisms are likely weak due to artificially low wolf densities. Using 13 years of data on 280 collared wolves in Yellowstone National Park, we assessed the effect of wolf density, prey abundance and population structure, as well as winter severity, on age-specific survival in two areas (prey-rich vs. prey-poor) of the national park. We further analysed cause-specific mortality and explored the factors driving intraspecific aggression in the prey-rich northern area of the park. Overall, survival rates decreased during the study. In northern Yellowstone, density dependence regulated adult survival through an increase in intraspecific aggression, independent of prey availability. In the interior of the park, adult survival was less variable and density-independent, despite reduced prey availability. There was no effect of prey population structure in northern Yellowstone, or of winter severity in either area. Survival was similar among yearlings and adults, but lower for adults older than 6 years. Our results indicate that density-dependent intraspecific aggression is a major driver of adult wolf survival in northern Yellowstone, suggesting intrinsic density-dependent mechanisms have the potential to regulate wolf populations at high ungulate densities. When low prey availability or high

Disparities in Adolescent and Young Adult Survival After Testicular Cancer Vary by Histologic Subtype: A Population-Based Study in California 1988-2010.

PubMed

DeRouen, Mindy C; Mujahid, Mahasin; Srinivas, Sandy; Keegan, Theresa H M

2016-03-01

Testicular cancer is the most common cancer among adolescent and young adult (AYA) men 15-39 years of age. This study aims to determine whether race/ethnicity and/or neighborhood socioeconomic status (SES) contribute independently to survival of AYAs with testicular cancer. Data on 14,249 eligible AYAs with testicular cancer diagnosed in California between 1988 and 2010 were obtained from the population-based California Cancer Registry. Multivariable Cox proportional hazards regression was used to examine overall and testicular cancer-specific survival and survival for the seminoma and nonseminoma histologic subtypes according to race/ethnicity, census-tract level neighborhood SES, and other patient and clinical characteristics. Compared with White AYAs, Hispanic AYAs had worse overall and testicular cancer-specific survival (hazard ratio [HR], 1.21; 95% confidence interval [CI], 1.07-1.37) and Black AYAs had worse overall survival (HR, 1.41; 95% CI, 1.01-1.97), independent of neighborhood SES and other demographic and clinical factors. Racial/ethnic disparities in survival were more pronounced for nonseminoma than for seminoma. AYAs residing in middle and low SES neighborhoods experienced worse survival across both histologic subtypes independent of race/ethnicity and other factors, while improvements in survival over time were more pronounced for seminoma. Longer time to treatment was also associated with worse survival, particularly for AYAs with nonseminoma. Among AYAs, race/ethnicity, and neighborhood SES are independently associated with survival after testicular cancer. Variation in disparities by histologic type according to demographic factors, year of diagnosis, and time to treatment may reflect differences in prognosis and extent of treatment for the two histologies.

Determinants of the relationship between cost and survival time after elective adult cardiac surgery.

PubMed

Ho, K M

2014-05-01

Cardiac surgery is increasingly performed on elderly patients with multiple comorbid conditions, but the determinants of the relationship between cost and survival time after cardiac surgery for patients with a serious cardiac condition remain uncertain. Using the long-term outcome data of a cohort study on adult cardiac surgical patients, the relationship between cost and survival time after cardiac surgery from a hospital service perspective was determined. The total cost for each patient was estimated by the costs of the surgical procedures, intra-aortic balloon pump utilisation, operating theatre utilisation, blood products, intensive care unit stay and cumulative hospital stay up to a median follow-up time of 30 months. Of the 2131 patients considered in this study, a total cost >A$100,000 per life-year after cardiac surgery was observed only in 171 patients (8.0%, 95% confidence interval 6.9 to 9.3%). Age, Charlson Comorbidity Index and EuroSCORE were all related to the cost per life-year after cardiac surgery, but EuroSCORE (odds ratio 1.26 per score increment, 95% confidence interval 1.18 to 1.35, P=0.001) was, by far, the most important determinant and explained 32% of the variability in cost per life-year after cardiac surgery. Patients with a high EuroSCORE were associated with a substantially longer length of intensive care unit stay and cumulative hospital stay, as well as a shorter survival time after cardiac surgery compared to patients with a lower EuroSCORE. Of all the subgroups of patients examined, only patients with a EuroSCORE >5 were consistently associated with a cost >A$100,000 per life-year (cost per life-year $183,148, 95% confidence interval 125, 394 to 240, 902).

Multiple interactions and rapidity gap survival

NASA Astrophysics Data System (ADS)

Khoze, V. A.; Martin, A. D.; Ryskin, M. G.

2018-05-01

Observations of rare processes containing large rapidity gaps at high energy colliders may be exceptionally informative. However the cross sections of these events are small in comparison with that for the inclusive processes since there is a large probability that the gaps may be filled by secondary particles arising from additional soft interactions or from gluon radiation. Here we review the calculations of the probability that the gaps survive population by particles from these effects for a wide range of different processes.

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

USGS Publications Warehouse

Esler, Daniel N.; 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

Praziquantel decreases fecundity in Schistosoma mansoni adult worms that survive treatment: evidence from a laboratory life-history trade-offs selection study.

PubMed

Lamberton, Poppy H L; Faust, Christina L; Webster, Joanne P

2017-06-16

Mass drug administration of praziquantel is the World Health Organization's endorsed control strategy for schistosomiasis. A decade of annual treatments across sub-Saharan Africa has resulted in significant reductions of infection prevalence and intensity levels, although 'hotspots' remain. Repeated drug treatments place strong selective pressures on parasites, which may affect life-history traits that impact transmission dynamics. Understanding drug treatment responses and the evolution of such traits can help inform on how to minimise the risk of drug resistance developing, maximise sustainable control programme success, and improve diagnostic protocols. We performed a four-generation Schistosoma mansoni praziquantel selection experiment in mice and snails. We used three S. mansoni lines: a praziquantel-resistant isolate (R), a praziquantel-susceptible isolate (S), and a co-infected line (RS), under three treatment regimens: untreated, 25 mg/kg praziquantel, or 50 mg/kg praziquantel. Life-history traits, including parasite adult-worm establishment, survival, reproduction (fecundity), and associated morbidity, were recorded in mice across all four generations. Predictor variables were tested in a series of generalized linear mixed effects models to determine which factors had a significant influence on parasite life-history traits in definitive hosts under different selection regimes. Praziquantel pressure significantly reduced adult-worm burdens across all generations and isolates, including within R-lines. However, previous drug treatment resulted in an increase in adult-worm establishment with increasing generation from P1 to F3. The highest worm numbers were in the co-infected RS line. Praziquantel treatment decreased adult-worm burden, but had a larger negative impact on the mean daily number of miracidia, a proxy for fecundity, across all three parasite isolates. Our predicted cost of resistance was not supported by the traits we measured within the

Age-specific survival estimates of King Eiders derived from satellite telemetry

USGS Publications Warehouse

Oppel, Steffen; Powell, Abby N.

2010-01-01

Age- and sex-specific survival and dispersal are important components in the dynamics and genetic structure of bird populations. For many avian taxa survival rates at the adult and juvenile life stages differ, but in long-lived species juveniles' survival is logistically challenging to study. We present the first estimates of hatch-year annual survival rates for a sea duck, the King Eider (Somateria spectabilis), estimated from satellite telemetry. From 2006 to 2008 we equipped pre-fiedging King Eiders with satellite transmitters on breeding grounds in Alaska and estimated annual survival rates during their first 2 years of life with known-fate models. We compared those estimates to survival rates of adults marked in the same area from 2002 to 2008. Hatch-year survival varied by season during the first year of life, and model-averaged annual survival rate was 0.67 (95% CI: 0.48–0.80). We did not record any mortality during the second year and were therefore unable to estimate second-year survival rate. Adults' survival rate was constant through the year (0.94, 95% CI: 0.86–0.97). No birds appeared to breed during their second summer. While 88% of females with an active transmitter (n = 9) returned to their natal area at the age of 2 years, none of the 2-year old males (n = 3) did. This pattern indicates that females' natal philopatry is high and suggests that males' higher rates of dispersal may account for sex-specific differences in apparent survival rates of juvenile sea ducks when estimated with mark—recapture methods.

Trisomy 13 (Patau syndrome) with an 11-year survival.

PubMed

Zoll, B; Wolf, J; Lensing-Hebben, D; Pruggmayer, M; Thorpe, B

1993-01-01

Trisomy 13 is very rare in live-born children. Only a small number of these children survive the first year and very few cases are reported to live longer. Survival time depends partly on the cytogenetic findings--full trisomy 13 or trisomy 13 mosaicism--and partly on the existence of serious somatic malformations. We report on a 11-year-old girl with full trisomy 13. In this case, missing cerebral and cardiovascular malformations probably allowed the long survival.

[En bloc renal transplant from infant donors to adults].

PubMed

Gómez Vegas, A; Blázquez Izquierdo, J; Pérez Contín, M J; Grimalt Alvarez, J; Rabadán Marina, M; Hermida Gutiérrez, J F; Prats, D; Resel Estévez, L

1998-12-01

To analyze the medium-term outcome of en bloc transplantation of pediatric kidneys into adult patients, including the incidence and type of surgical complications. From November 1991 to December 1997, we performed 37 en bloc transplantation of pediatric kidneys into adult patients. The kidneys were harvested from donors less that 3 years old and/or weighing 15 kg. The mean follow-up was 24 months. Grafting was achieved by end-to-side anastomosis of the donor cava to the receptor external iliac and the aortic patch to the external iliac artery. Three grafts failed, probably due to hilar torsion; the remaining were initially functioning well. Seven transplant removal were performed; 6 were due to thrombosis. The actuarial graft survival was 89.1% at one month, 80.83% at 12 months and 80.83% at 24 months. The medium-term results of en bloc transplantation of pediatric kidneys into adult patients were excellent and demonstrate the efficacy of this type of grafts. Arterial and venous thrombosis were the most important complications, quantitatively and qualitatively.

No survival benefit to gaining private health insurance coverage for post-lung transplant care in adults with cystic fibrosis.