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  1. Linking age, survival, and transit time distributions

    Science.gov (United States)

    Calabrese, Salvatore; Porporato, Amilcare

    2015-10-01

    Although the concepts of age, survival, and transit time have been widely used in many fields, including population dynamics, chemical engineering, and hydrology, a comprehensive mathematical framework is still missing. Here we discuss several relationships among these quantities by starting from the evolution equation for the joint distribution of age and survival, from which the equations for age and survival time readily follow. It also becomes apparent how the statistical dependence between age and survival is directly related to either the age dependence of the loss function or the survival-time dependence of the input function. The solution of the joint distribution equation also allows us to obtain the relationships between the age at exit (or death) and the survival time at input (or birth), as well as to stress the symmetries of the various distributions under time reversal. The transit time is then obtained as a sum of the age and survival time, and its properties are discussed along with the general relationships between their mean values. The special case of steady state case is analyzed in detail. Some examples, inspired by hydrologic applications, are presented to illustrate the theory with the specific results. This article was corrected on 11 Nov 2015. See the end of the full text for details.

  2. Regression analysis of restricted mean survival time based on pseudo-observations

    DEFF Research Database (Denmark)

    Andersen, Per Kragh; Hansen, Mette Gerster; Klein, John P.

    censoring; hazard function; health economics; regression model; survival analysis; mean survival time; restricted mean survival time; pseudo-observations......censoring; hazard function; health economics; regression model; survival analysis; mean survival time; restricted mean survival time; pseudo-observations...

  3. Regression Analysis of Restricted Mean Survival Time Based on Pseudo-Observations

    DEFF Research Database (Denmark)

    Andersen, Per Kragh; Hansen, Mette Gerster; Klein, John P.

    2004-01-01

    censoring; hazard function; health economics; mean survival time; pseudo-observations; regression model; restricted mean survival time; survival analysis......censoring; hazard function; health economics; mean survival time; pseudo-observations; regression model; restricted mean survival time; survival analysis...

  4. A generalized additive regression model for survival times

    DEFF Research Database (Denmark)

    Scheike, Thomas H.

    2001-01-01

    Additive Aalen model; counting process; disability model; illness-death model; generalized additive models; multiple time-scales; non-parametric estimation; survival data; varying-coefficient models......Additive Aalen model; counting process; disability model; illness-death model; generalized additive models; multiple time-scales; non-parametric estimation; survival data; varying-coefficient models...

  5. Cranial trauma and the assessment of posttraumatic survival time

    NARCIS (Netherlands)

    Steyn, M.; de Boer, H. H. [=Hans H.; van der Merwe, A. E.

    2014-01-01

    Assessment of trauma on skeletal remains can be very difficult, especially when it comes to the estimation of posttraumatic survival time in partially healed lesions. The ability to reliably estimate the time an individual has survived after sustaining an injury is especially important in cases of

  6. Time series modeling of system self-assessment of survival

    Energy Technology Data Exchange (ETDEWEB)

    Lu, H.; Kolarik, W.J. [Texas Tech Univ., Lubbock, TX (United States). Dept. of Industrial Engineering

    1999-06-01

    Self-assessment of survival for a system, subsystem or component is implemented by assessing conditional performance reliability in real-time, which includes modeling and analysis of physical performance data. This paper proposes a time series analysis approach to system self-assessment (prediction) of survival. In the approach, physical performance data are modeled in a time series. The performance forecast is based on the model developed and is converted to the reliability of system survival. In contrast to a standard regression model, a time series model, using on-line data, is suitable for the real-time performance prediction. This paper illustrates an example of time series modeling and survival assessment, regarding an excessive tool edge wear failure mode for a twist drill operation.

  7. Red cell survival time in chronic renal failure

    Energy Technology Data Exchange (ETDEWEB)

    Rath, R.N.; Das, R.K.; Panda, R.K.; Mahakur, A.C.; Patnaik, S.R. (M.K.C.G. Medical College, Berhampur (India))

    1979-10-01

    The red cell survival time was estimated in 50 cases of chronic renal failure and 20 healthy subjects, using radioactive chromium /sup 51/Cr. The mean value of red cell survival half time (T1/2/sup 51/Cr) was determined to be 25.9 +- 1.1 days in control subjects. The red cell survival half time (17.9 +- 4.67 days) was found to be significantly decreased in cases of chronic renal failure, when compared to the control group. An inverse relationship was observed between T1/2/sup 51/Cr value and blood urea, serum creatinine, the magnitude of hypertension, and duration of illness, whereas, creatinine clearance showed a direct relationship. There was no increased splenic uptake of radioactive chromium, indicating that haemolysis occurred elsewhere in the circulation other than spleen. The possible mechanism for the reduction of red cell survival time and the effect of uraemic environment on it has been discussed.

  8. Piecewise exponential survival trees with time-dependent covariates.

    Science.gov (United States)

    Huang, X; Chen, S; Soong, S J

    1998-12-01

    Survival trees methods are nonparametric alternatives to the semiparametric Cox regression in survival analysis. In this paper, a tree-based method for censored survival data with time-dependent covariates is proposed. The proposed method assumes a very general model for the hazard function and is fully nonparametric. The recursive partitioning algorithm uses the likelihood estimation procedure to grow trees under a piecewise exponential structure that handles time-dependent covariates in a parallel way to time-independent covariates. In general, the estimated hazard at a node gives the risk for a group of individuals during a specific time period. Both cross-validation and bootstrap resampling techniques are implemented in the tree selection procedure. The performance of the proposed survival trees method is shown to be good through simulation and application to real data.

  9. Survival time of direct dental restorations in adults

    Directory of Open Access Journals (Sweden)

    Thaís Torres Barros Dutra

    Full Text Available AbstractIntroductionThe presence of dental caries is the main reason for the placement and replacement of restorations. Maintaining restorations to a satisfactory clinical condition is a challenge, despite the evolution of materials and surgical operative techniques.ObjectiveTo investigate the survival time and technical-operatory characteristics of dental restorations among adults in Teresina-PI.Material and methodData collection was carried out from September 2009 to January 2010 at a non-profit dental service. Data were collected at the moment of restoration replacement. The sample consisted of 262 defective restorations in 139 individuals. Survival time was calculated using the placement date that was registered on the individual’s dental form. Kruskal-Wallis and Mann-Whitney tests were used to compare the survival time of the different types of restorations and the chi-square test was used to assess the association between qualitative variables, at a 5% significance level.ResultThe median survival time of the restorations was 2 years. The survival time for amalgam was higher than for composite and glass ionomer cement (p=0.004. The most replaced dental material was the composite (66.4%. The majority of the replaced restorations had been placed in anterior teeth, in proximal surfaces.ConclusionAmalgam restorations have a longer survival time than composite resin. Technical and operatory variables had no influence on the survival time of restorations. Dental restorations have a low survival time and this fact might be associated with the decion-making process that is adopted by the professionals.

  10. Graphing survival curve estimates for time-dependent covariates.

    Science.gov (United States)

    Schultz, Lonni R; Peterson, Edward L; Breslau, Naomi

    2002-01-01

    Graphical representation of statistical results is often used to assist readers in the interpretation of the findings. This is especially true for survival analysis where there is an interest in explaining the patterns of survival over time for specific covariates. For fixed categorical covariates, such as a group membership indicator, Kaplan-Meier estimates (1958) can be used to display the curves. For time-dependent covariates this method may not be adequate. Simon and Makuch (1984) proposed a technique that evaluates the covariate status of the individuals remaining at risk at each event time. The method takes into account the change in an individual's covariate status over time. The survival computations are the same as the Kaplan-Meier method, in that the conditional survival estimates are the function of the ratio of the number of events to the number at risk at each event time. The difference between the two methods is that the individuals at risk within each level defined by the covariate is not fixed at time 0 in the Simon and Makuch method as it is with the Kaplan-Meier method. Examples of how the two methods can differ for time dependent covariates in Cox proportional hazards regression analysis are presented.

  11. Investigation of survival time of some poultry mycoplasmas.

    Science.gov (United States)

    Simon, A; Tamasi, G; Stipkovits, L

    1989-01-01

    Glucose-fermenting poultry mycoplasmas (Mycoplasma [M.] gallisepticum, M. pullorum, M. gallinaceum, M. gallopavonis) were tested in 2 experiments for their survival time at 20 degrees C and 37 degrees C on 18 different materials used on farms and in hatcheries. All mycoplasmas survived up to 16 days in egg yolk at both temperatures. On other materials, like egg shell, egg white, paper trails, feather, and others mycoplasmas generally survived 2 to 16 days at 20 degrees C. M. gallinaceum and M. gallopavonis proved more resistant to the environment than M. gallisepticum and M. pullorum.

  12. effect of liquid nitrogen storage time on the survival and ...

    African Journals Online (AJOL)

    Administrator

    Investigations were undertaken on the effect of liquid nitrogen (LN) storage time on survival and regeneration of somatic embryos of cocoa (Theobroma cacao l.). Somatic embryos from different cocoa genotypes (AMAZ 3-. 2, AMAZ 10-1, AMAZ 12, SIAL 93, and IMC 14) at 15.45% moisture content were cryopreserved in LN ...

  13. Effect of liquid nitrogen storage time on the survival and ...

    African Journals Online (AJOL)

    Investigations were undertaken on the effect of liquid nitrogen (LN) storage time on survival and regeneration of somatic embryos of cocoa (Theobroma cacao l.). Somatic embryos from different cocoa genotypes (AMAZ 3-2, AMAZ 10-1, AMAZ 12, SIAL 93, and IMC 14) at 15.45% moisture content were cryopreserved in LN ...

  14. Survival-time statistics for sample space reducing stochastic processes.

    Science.gov (United States)

    Yadav, Avinash Chand

    2016-04-01

    Stochastic processes wherein the size of the state space is changing as a function of time offer models for the emergence of scale-invariant features observed in complex systems. I consider such a sample-space reducing (SSR) stochastic process that results in a random sequence of strictly decreasing integers {x(t)},0≤t≤τ, with boundary conditions x(0)=N and x(τ) = 1. This model is shown to be exactly solvable: P_{N}(τ), the probability that the process survives for time τ is analytically evaluated. In the limit of large N, the asymptotic form of this probability distribution is Gaussian, with mean and variance both varying logarithmically with system size: 〈τ〉∼lnN and σ_{τ}^{2}∼lnN. Correspondence can be made between survival-time statistics in the SSR process and record statistics of independent and identically distributed random variables.

  15. Five-year survival and median survival time of nasopharyngeal carcinoma in Hospital Universiti Sains Malaysia.

    Science.gov (United States)

    Siti-Azrin, Ab Hamid; Norsa'adah, Bachok; Naing, Nyi Nyi

    2014-01-01

    Nasopharyngeal carcinoma (NPC) is the fourth most common cancer in Malaysia. The objective of this study was to determine the five-year survival rate and median survival time of NPC patients in Hospital Universiti Sains Malaysia (USM). One hundred and thirty four NPC cases confirmed by histopathology in Hospital USM between 1st January 1998 and 31st December 2007 that fulfilled the inclusion and exclusion criteria were retrospectively reviewed. Survival time of NPC patients were estimated by Kaplan-Meier survival analysis. Log-rank tests were performed to compare survival of cases among presenting symptoms, WHO type, TNM classification and treatment modalities. The overall five-year survival rate of NPC patients was 38.0% (95% confidence interval (CI): 29.1, 46.9). The overall median survival time of NPC patients was 31.30 months (95%CI: 23.76, 38.84). The significant factors that altered the survival rate and time were age (p=0.041), cranial nerve involvement (p=0.012), stage (p=0.002), metastases (p=0.008) and treatment (p<0.001). The median survival of NPC patients is significantly longer for age≤50 years, no cranial nerve involvement, and early stage and is dependent on treatment modalities.

  16. Integral Time and the Varieties of Post-Mortem Survival

    Directory of Open Access Journals (Sweden)

    Sean M. Kelly

    2008-06-01

    Full Text Available While the question of survival of bodily death is usually approached by focusing on the mind/body relation (and often with the idea of the soul as a special kind of substance, this paper explores the issue in the context of our understanding of time. The argument of the paper is woven around the central intuition of time as an “ever-living present.” The development of this intuition allows for a more integral or “complex-holistic” theory of time, the soul, and the question of survival. Following the introductory matter, the first section proposes a re-interpretation of Nietzsche’s doctrine of eternal recurrence in terms of moments and lives as “eternally occurring.” The next section is a treatment of Julian Barbour’s neo-Machian model of instants of time as configurations in the n-dimensional phase-space he calls “Platonia.” While rejecting his claim to have done away with time, I do find his model suggestive of the idea of moments and lives as eternally occurring. The following section begins with Fechner’s visionary ideas of the nature of the soul and its survival of bodily death, with particular attention to the notion of holonic inclusion and the central analogy of the transition from perception to memory. I turn next to Whitehead’s equally holonic notions of prehension and the concrescence of actual occasions. From his epochal theory of time and certain ambiguities in his reflections on the “divine antinomies,” we are brought to the threshold of a potentially more integral or “complex-holistic” theory of time and survival, which is treated in the last section. This section draws from my earlier work on Hegel, Jung, and Edgar Morin, as well as from key insights of Jean Gebser, for an interpretation of Sri Aurobindo’s inspired but cryptic description of the “Supramental Time Vision.” This interpretation leads to an alternative understanding of reincarnation—and to the possibility of its reconciliation

  17. Estimation of diver survival time in a lost bell

    Energy Technology Data Exchange (ETDEWEB)

    Tipton, M.J.; Franks, C. [Surrey Univ., Guildford (United Kingdom); Meneilly, G.S. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Medicine; Mekjavic, I.B. [Simon Fraser University, Vancouver (Canada). Dept. of Kinesiology

    1997-04-01

    Mathematical models of the human thermoregulatory system have been used to make predictions of the likely survival of divers in a ``lost bell`` who can be exposed to very low ambient temperatures. The circumstances considered are not the most extreme but those where, partly by shivering, the individual can re-enter thermal balance. The ability accurately to predict the level and duration of metabolic heat production is critical for the estimation of survival time under these conditions. Limitations on the accuracy of current models arise from the lack of precision in modelling the intensity and duration of the metabolic (shivering) response. A different basis for predicting shivering endurance using the time to hypogylcaemia (blood glucose level less than 2.5 mmol/1) is proposed. This leads to predicted survival times ranging from 10 to over 24 hours for those individuals able to stabilise deep body temperature. This seems to be more consistent with the limited experimental data which exists than the 8-9 hours predicted by other models. In order to help maintain blood sugar levels, and hence metabolic heat production, it is recommended that emergency rations within bells should provide 500g of carbohydrate a day. (59 figures; 221 references). (UK)

  18. Time dependent ethnic convergence in colorectal cancer survival in hawaii

    Directory of Open Access Journals (Sweden)

    Hundahl Scott A

    2003-02-01

    Full Text Available Abstract Background Although colorectal cancer death rates have been declining, this trend is not consistent across all ethnic groups. Biological, environmental, behavioral and socioeconomic explanations exist, but the reason for this discrepancy remains inconclusive. We examined the hypothesis that improved cancer screening across all ethnic groups will reduce ethnic differences in colorectal cancer survival. Methods Through the Hawaii Tumor Registry 16,424 patients diagnosed with colorectal cancer were identified during the years 1960–2000. Cox regression analyses were performed for each of three cohorts stratified by ethnicity (Caucasian, Japanese, Hawaiian, Filipino, and Chinese. The models included stage of diagnosis, year of diagnosis, age, and sex as predictors of survival. Results Mortality rates improved significantly for all ethnic groups. Moreover, with the exception of Hawaiians, rates for all ethnic groups converged over time. Persistently lower survival for Hawaiians appeared linked with more cancer treatment. Conclusion Ethnic disparities in colorectal cancer mortality rates appear primarily the result of differential utilization of health care. If modern screening procedures can be provided equally to all ethnic groups, ethnic outcome differences can be virtually eliminated.

  19. Rubber dam may increase the survival time of dental restorations.

    Science.gov (United States)

    Keys, William; Carson, Susan J

    2017-03-01

    Data sourcesCochrane Oral Health's Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), Medline, Embase, LILACS, SciELO, Chinese BioMedical Literature Database, VIP, China National Knowledge Infrastructure, ClinicalTrials.gov, World Health Organization International Clinical Trials Registry Platform, OpenGrey and Sciencepaper Online databases. Handsearches in a number of journals.Study selectionRandomised controlled trials, including split-mouth studies assessing the effects of rubber dam isolation for restorative treatments in dental patients.Data extraction and synthesisTwo review authors independently screened the results of the electronic searches, extracted data and assessed the risk of bias of the included studies.ResultsFour studies involving a total of 1,270 patients were included. The studies were at high risk of bias. One trial was excluded from the analysis due to inconsistencies in the presented data. Restorations had a significantly higher survival rate in the rubber dam isolation group compared to the cotton roll isolation group at six months in participants receiving composite restorative treatment of non-carious cervical lesions (risk ratio (RR) 1.19, 95% confidence interval (CI) 1.04 to 1.37, very low-quality evidence). The rubber dam group had a lower risk of failure at two years in children undergoing proximal atraumatic restorative treatment in primary molars (hazard ratio (HR) 0.80, 95% CI 0.66 to 0.97, very low-quality evidence). One trial reported limited data showing that rubber dam usage during fissure sealing might shorten the treatment time. None of the included studies mentioned adverse effects or reported the direct cost of the treatment, or the level of patient acceptance/satisfaction. There was also no evidence evaluating the effects of rubber dam usage on the quality of the restorations.ConclusionsWe found some very low-quality evidence, from single studies, suggesting that rubber dam usage in dental direct

  20. Semiparametric Methods to Contrast Gap Time Survival Functions: Application to Repeat Kidney Transplantation

    OpenAIRE

    Shu, Xu; Schaubel, Douglas E.

    2015-01-01

    Times between successive events (i.e., gap times) are of great importance in survival analysis. Although many methods exist for estimating covariate effects on gap times, very few existing methods allow for comparisons between gap times themselves. Motivated by the comparison of primary and repeat transplantation, our interest is specifically in contrasting the gap time survival functions and their integration (restricted mean gap time). Two major challenges in gap time analysis are non-ident...

  1. Surviving in a metastable de Sitter space-time

    Energy Technology Data Exchange (ETDEWEB)

    Kashyap, Sitender Pratap; Mondal, Swapnamay [Harish-Chandra Research Institute,Chhatnag Road, Jhusi, Allahabad 211019 (India); Sen, Ashoke [Harish-Chandra Research Institute,Chhatnag Road, Jhusi, Allahabad 211019 (India); School of Physics, Korea Institute for Advanced Study,Seoul 130-722 (Korea, Republic of); Verma, Mritunjay [Harish-Chandra Research Institute,Chhatnag Road, Jhusi, Allahabad 211019 (India); International Centre for Theoretical Sciences,Malleshwaram, Bengaluru 560 012 (India)

    2015-09-21

    In a metastable de Sitter space any object has a finite life expectancy beyond which it undergoes vacuum decay. However, by spreading into different parts of the universe which will fall out of causal contact of each other in future, a civilization can increase its collective life expectancy, defined as the average time after which the last settlement disappears due to vacuum decay. We study in detail the collective life expectancy of two comoving objects in de Sitter space as a function of the initial separation, the horizon radius and the vacuum decay rate. We find that even with a modest initial separation, the collective life expectancy can reach a value close to the maximum possible value of 1.5 times that of the individual object if the decay rate is less than 1% of the expansion rate. Our analysis can be generalized to any number of objects, general trajectories not necessarily at rest in the comoving coordinates and general FRW space-time. As part of our analysis we find that in the current state of the universe dominated by matter and cosmological constant, the vacuum decay rate is increasing as a function of time due to accelerated expansion of the volume of the past light cone. Present decay rate is about 3.7 times larger than the average decay rate in the past and the final decay rate in the cosmological constant dominated epoch will be about 56 times larger than the average decay rate in the past. This considerably weakens the lower bound on the half-life of our universe based on its current age.

  2. Improving lung cancer survival: Time to move on

    NARCIS (Netherlands)

    M.E. Heuvers (Marlies)

    2013-01-01

    markdownabstract__Abstract__ In 1761, lung cancer was first described as a distinct disease based on autopsies by Giovanni Morgagni. In 1810, Gaspard Laurent Bayle described lung cancer in more detail in his book entitled Recherches sur la phthisie pulmonaire. At that time it was an extremely

  3. Improving lung cancer survival; time to move on

    NARCIS (Netherlands)

    M.E. Heuvers (Marlies); J.P.J.J. Hegmans (Joost); B.H.Ch. Stricker (Bruno); J.G.J.V. Aerts (Joachim)

    2012-01-01

    textabstractBackground: During the past decades, numerous efforts have been made to decrease the death rate among lung cancer patients. Nonetheless, the improvement in long-term survival has been limited and lung cancer is still a devastating disease.Discussion: With this article we would like to

  4. Survey Article: Ukraine's Industrial Enterprise: Surviving Hard Times

    OpenAIRE

    Fyodor I Kushnirsky

    1994-01-01

    Ukraine's industrial organizational structure, retaining the features of a planned system, has been slow to change. The state plays a greater role in controlling industrial production there than in Russia. Along with privatization, the government encourages different types of associations and conglomerates. Industry's dismal performance could probably be worse without surviving strategies used by enterprise management, such as retaining working collectives, loyalty to suppliers and buyers, av...

  5. Examining the Influence of Campus Climate on Students' Time to Degree: A Multilevel Discrete-Time Survival Analysis

    Science.gov (United States)

    Zhou, Ji; Castellanos, Michelle

    2013-01-01

    Utilizing longitudinal data of 3477 students from 28 institutions, we examine the effects of structural diversity and quality of interracial relation on students' persistence towards graduation within six years. We utilize multilevel discrete-time survival analysis to account for the longitudinal persistence patterns as well as the nested…

  6. Survival probability and first-passage-time statistics of a Wiener process driven by an exponential time-dependent drift

    Science.gov (United States)

    Urdapilleta, Eugenio

    2011-02-01

    The survival probability and the first-passage-time statistics are important quantities in different fields. The Wiener process is the simplest stochastic process with continuous variables, and important results can be explicitly found from it. The presence of a constant drift does not modify its simplicity; however, when the process has a time-dependent component the analysis becomes difficult. In this work we analyze the statistical properties of the Wiener process with an absorbing boundary, under the effect of an exponential time-dependent drift. Based on the backward Fokker-Planck formalism we set the time-inhomogeneous equation and conditions that rule the diffusion of the corresponding survival probability. We propose as the solution an expansion series in terms of the intensity of the exponential drift, resulting in a set of recurrence equations. We explicitly solve the expansion up to second order and comment on higher-order solutions. The first-passage-time density function arises naturally from the survival probability and preserves the proposed expansion. Explicit results, related properties, and limit behaviors are analyzed and extensively compared to numerical simulations.

  7. Survival probability and first-passage-time statistics of a Wiener process driven by an exponential time-dependent drift.

    Science.gov (United States)

    Urdapilleta, Eugenio

    2011-02-01

    The survival probability and the first-passage-time statistics are important quantities in different fields. The Wiener process is the simplest stochastic process with continuous variables, and important results can be explicitly found from it. The presence of a constant drift does not modify its simplicity; however, when the process has a time-dependent component the analysis becomes difficult. In this work we analyze the statistical properties of the Wiener process with an absorbing boundary, under the effect of an exponential time-dependent drift. Based on the backward Fokker-Planck formalism we set the time-inhomogeneous equation and conditions that rule the diffusion of the corresponding survival probability. We propose as the solution an expansion series in terms of the intensity of the exponential drift, resulting in a set of recurrence equations. We explicitly solve the expansion up to second order and comment on higher-order solutions. The first-passage-time density function arises naturally from the survival probability and preserves the proposed expansion. Explicit results, related properties, and limit behaviors are analyzed and extensively compared to numerical simulations.

  8. Assessment of lead-time bias in estimates of relative survival for breast cancer.

    Science.gov (United States)

    Andersson, Therese M-L; Rutherford, Mark J; Humphreys, Keith

    2017-02-01

    Relative survival ratios (RSRs) can be useful for evaluating the impact of changes in cancer care on the prognosis of cancer patients or for comparing the prognosis for different subgroups of patients, but their use is problematic for cancer sites where screening has been introduced due to the potential of lead-time bias. Lead-time is survival time that is added to a patient's survival time because of an earlier diagnosis irrespective of a possibly postponed time of death. In the presence of screening it is difficult to disentangle how much of an observed improvement in survival is real and how much is due to lead-time bias. Even so, RSRs are often presented for breast cancer, a site where screening has led to early diagnosis, with the assumption that the lead-time bias is small. We describe a simulation-based framework for studying the lead-time bias due to mammography screening on RSRs of breast cancer based on a natural history model developed in a Swedish setting. We have performed simulations, using this framework, under different assumptions for screening sensitivity and breast cancer survival with the aim of estimating the lead-time bias. Screening every second year among ages 40-75 was introduced assuming that screening had no effect on survival, except for lead-time bias. Relative survival was estimated both with and without screening to enable quantification of the lead-time bias. Scenarios with low, moderate and high breast cancer survival, and low, moderate and high screening sensitivity were simulated, and the lead-time bias assessed in all scenarios. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Preoperative Nutritional Risk Index to predict postoperative survival time in primary liver cancer patients.

    Science.gov (United States)

    Bo, Yacong; Yao, Mingjie; Zhang, Ling; Bekalo, Wolde; Lu, Weiquan; Lu, Quanjun

    2015-01-01

    We designed this study to determine the predictive value of Nutritional Risk Index (NRI) for postoperative survival time of patients who had undergone hepatectomy for primary liver cancer. The 620 patients who underwent hepatectomy for primary liver cancer (PLC) in the Department of Hepatobiliary Surgery, Cancer Hospital of Henan Province, Zhengzhou, China from December 1, 2008 to December 1, 2012 were followed up. A nutritional risk index (NRI) was used to screen the patients with malnutrition (NRI100) patients had longer postoperative survival time compared with malnourished patients. NRI values>100 was sig-nificantly associated with longer postoperative survival time. Cox proportional hazards model showed that NRI was an independent predictor of postoperative survival time and that NRI varied inversely with the risk of death. The patients with NRI values>100 survived longer than those with NRI values

  10. Lessons from Cacti: How to Survive the Prickles of Life during Tough Times

    Science.gov (United States)

    Bigger, Alan S.; Bigger, Linda B.

    2009-01-01

    The saguaro cactus looked a little like humans, in different shapes and sizes. How on earth do they survive in a climate that seems so inhospitable? It is possible to learn lessons for life from a cactus, if one can only get beyond the thorns, and that these lessons will assist one to survive during tough or prickly times. These plants survive…

  11. Survival times for canine intranasal sarcomas treated with radiation therapy: 86 cases (1996-2011).

    Science.gov (United States)

    Sones, Evan; Smith, Annette; Schleis, Stephanie; Brawner, William; Almond, Gregory; Taylor, Kathryn; Haney, Siobhan; Wypij, Jackie; Keyerleber, Michele; Arthur, Jennifer; Hamilton, Terrance; Lawrence, Jessica; Gieger, Tracy; Sellon, Rance; Wright, Zack

    2013-01-01

    Sarcomas comprise approximately one-third of canine intranasal tumors, however few veterinary studies have described survival times of dogs with histologic subtypes of sarcomas separately from other intranasal tumors. One objective of this study was to describe median survival times for dogs treated with radiation therapy for intranasal sarcomas. A second objective was to compare survival times for dogs treated with three radiation therapy protocols: daily-fractionated radiation therapy; Monday, Wednesday, and Friday fractionated radiation therapy; and palliative radiation therapy. Medical records were retrospectively reviewed for dogs that had been treated with radiation therapy for confirmed intranasal sarcoma. A total of 86 dogs met inclusion criteria. Overall median survival time for included dogs was 444 days. Median survival time for dogs with chondrosarcoma (n = 42) was 463 days, fibrosarcoma (n = 12) 379 days, osteosarcoma (n = 6) 624 days, and undifferentiated sarcoma (n = 22) 344 days. Dogs treated with daily-fractionated radiation therapy protocols; Monday, Wednesday and Friday fractionated radiation therapy protocols; and palliative radiation therapy protocols had median survival times of 641, 347, and 305 days, respectively. A significant difference in survival time was found for dogs receiving curative intent radiation therapy vs. palliative radiation therapy (P = 0.032). A significant difference in survival time was also found for dogs receiving daily-fractionated radiation therapy vs. Monday, Wednesday and Friday fractionated radiation therapy (P = 0.0134). Findings from this study support the use of curative intent radiation therapy for dogs with intranasal sarcoma. Future prospective, randomized trials are needed for confirmation of treatment benefits. © 2012 Veterinary Radiology & Ultrasound.

  12. Radiographic response to locoregional therapy in hepatocellular carcinoma predicts patient survival times.

    Science.gov (United States)

    Memon, Khairuddin; Kulik, Laura; Lewandowski, Robert J; Wang, Edward; Riaz, Ahsun; Ryu, Robert K; Sato, Kent T; Marshall, Karen; Gupta, Ramona; Nikolaidis, Paul; Miller, Frank H; Yaghmai, Vahid; Senthilnathan, Seanthan; Baker, Talia; Gates, Vanessa L; Abecassis, Michael; Benson, Al B; Mulcahy, Mary F; Omary, Reed A; Salem, Riad

    2011-08-01

    It is not clear whether survival times of patients with hepatocellular carcinoma (HCC) are associated with their response to therapy. We analyzed the association between tumor response and survival times of patients with HCC who were treated with locoregional therapies (LRTs) (chemoembolization and radioembolization). Patients received LRTs over a 9-year period (n = 463). Patients with metastases, portal venous thrombosis, or who had received transplants were excluded; 159 patients with Child-Pugh B7 or lower were analyzed. Response (based on European Association for the Study of the Liver [EASL] and World Health Organization [WHO] criteria) was associated with survival times using the landmark, risk-of-death, and Mantel-Byar methodologies. In a subanalysis, survival times of responders were compared with those of patients with stable disease and progressive disease. Based on 6-month data, in landmark analysis, responders survived longer than nonresponders (based on EASL but not WHO criteria: P = .002 and .0694). The risk of death was also lower for responders (based on EASL but not WHO criteria: P = .0463 and .707). Landmark analysis of 12-month data showed that responders survived longer than nonresponders (P < .0001 and .004, based on EASL and WHO criteria, respectively). The risk of death was lower for responders (P = .0132 and .010, based on EASL and WHO criteria, respectively). By the Mantel-Byar method, responders had longer survival than nonresponders, based on EASL criteria (P < .0001; P = .596 with WHO criteria). In the subanalysis, responders lived longer than patients with stable disease or progressive disease. Radiographic response to LRTs predicts survival time. EASL criteria for response more consistently predicted survival times than WHO criteria. The goal of LRT should be to achieve a radiologic response, rather than to stabilize disease. Copyright © 2011 AGA Institute. Published by Elsevier Inc. All rights reserved.

  13. List and liver transplant survival according to waiting time in patients with hepatocellular carcinoma.

    Science.gov (United States)

    Salvalaggio, P R; Felga, G; Axelrod, D A; Della Guardia, B; Almeida, M D; Rezende, M B

    2015-03-01

    The time that patients with hepatocellular carcinoma (HCC) can safely remain on the waiting list for liver transplantation (LT) is unknown. We investigated whether waiting time on the list impacts transplant survival of HCC candidates and transplant recipients. This is a single-center retrospective study of 283 adults with HCC. Patients were divided in groups according to waiting-list time. The main endpoint was survival. The median waiting time for LT was 4.9 months. The dropout rates at 3-, 6-, and 12-months were 6.4%, 12.4%, and 17.7%, respectively. Mortality on the list was 4.8%, but varied depending of the time on the list. Patients who waited less than 3-months had an inferior overall survival when compared to the other groups (p = 0.027). Prolonged time on the list significantly reduced mortality in this analysis (p = 0.02, HR = 0.28). Model for End Stage Liver Disease (MELD) score at transplantation did also independently impact overall survival (p = 0.03, HR = 1.06). MELD was the only factor that independently impacted posttransplant survival (p = 0.048, HR = 1.05). We conclude that waiting time had no relation with posttransplant survival. It is beneficial to prolong the waiting list time for HCC candidates without having a negative impact in posttransplant survival. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

  14. Tobit regression for modeling mean survival time using data subject to multiple sources of censoring.

    Science.gov (United States)

    Gong, Qi; Schaubel, Douglas E

    2018-01-22

    Mean survival time is often of inherent interest in medical and epidemiologic studies. In the presence of censoring and when covariate effects are of interest, Cox regression is the strong default, but mostly due to convenience and familiarity. When survival times are uncensored, covariate effects can be estimated as differences in mean survival through linear regression. Tobit regression can validly be performed through maximum likelihood when the censoring times are fixed (ie, known for each subject, even in cases where the outcome is observed). However, Tobit regression is generally inapplicable when the response is subject to random right censoring. We propose Tobit regression methods based on weighted maximum likelihood which are applicable to survival times subject to both fixed and random censoring times. Under the proposed approach, known right censoring is handled naturally through the Tobit model, with inverse probability of censoring weighting used to overcome random censoring. Essentially, the re-weighting data are intended to represent those that would have been observed in the absence of random censoring. We develop methods for estimating the Tobit regression parameter, then the population mean survival time. A closed form large-sample variance estimator is proposed for the regression parameter estimator, with a semiparametric bootstrap standard error estimator derived for the population mean. The proposed methods are easily implementable using standard software. Finite-sample properties are assessed through simulation. The methods are applied to a large cohort of patients wait-listed for kidney transplantation. Copyright © 2018 John Wiley & Sons, Ltd.

  15. Correlation between Pulmonary Function Indexes and Survival Time 
in Patients with Advanced Lung Cancer

    Directory of Open Access Journals (Sweden)

    Hui GE

    2013-07-01

    Full Text Available Background and objective To those patients with advanced lung cancer, the ultimate objective is to improve the curative effect and quality of life, lung function indexes are an important factor. We investigate the change of lung function and the relationship between pulmonary function indexs and survival time in patients with advanced lung cancer. Methods Lung function was detected in 59 cases with lung cancer and 63 normal controls. The relationship between pulmonary function indexs and survival time was analyzed. Results There was significant difference in ventilation function and diffusing capacity between in lung cancer group and control group. Vital capacity (VC, forced expiratory volume in one second (FEV1, forced vital capacity (FVC, peak expiratory flow (PEF, peak expiratory flow% (PEF%, maximal ventilatory volume (MVV were positively correlated with survival time in patients with advanced lung cancer (r=0.29, 0.28, 0.28, 0.27, 0.26, 0.28, P<0.05, residual volume/total lung capacity was negatively correlated with survival time (r=-0.31, P<0.05. Conclusion The lung function decreases in the patients with lung cancer. VC, FEV1, FVC, PEF, PEF%, MVV, residual volume/total lung capacity were correlated with survival time in patients with advanced lung cancer. The pulmonary function indexs were important marker of prognosis in patients with lung cancer.

  16. A Systematic Review of Testicle Survival Time After a Torsion Event.

    Science.gov (United States)

    Mellick, Larry Bruce; Sinex, James E; Gibson, Robert W; Mears, Kim

    2017-09-25

    The time window for possible salvage and survival of a torsed testicle is commonly thought to be 6 to 8 hours. However, survival of torsed testicles with or without subsequent atrophy is known to occur outside that critical time window. In this article, we performed a systematic review of the English literature to provide a more accurate understanding of reported time frames of testicle survival after a torsion event. The primary research question was to determine the relationship between time to treatment and the rate of survival for testicles of male patients presenting with testicular torsion (TT). A systematic review of the literature was performed and structured according to PRISMA guidelines. An exhaustive library search was performed after search strategies were developed for multiple databases that included PubMed, Cochrane library, Ovid MEDLINE, Web of Science, and ProQuest Theses and Dissertations. Two different searches were developed including "testicular torsion" and TT with the search term "time" added. Articles specifically reporting TT case series, testicle outcomes, and time to surgical or manual treatment were selected for review. In addition to and preceding the systematic review, an exhaustive manual search of the literature was also performed by the authors. As a result of these searches, a total of 30 studies with data considered relevant to the research question were included. The information extracted from the articles was tabulated with regard to time intervals to treatment and survival outcome. The systematic review process and protocol are reported in this article. A total of 30 studies were found that reported case series of TT patients and their outcomes as well as time to treatment reported in useful time frames. From these reports, a total of 2116 TT patients were culled, and their outcomes and time to treatment are reported. Because the time to treatment was reported variously in different case series, the 3 most common formats for

  17. Looking inward: The impact of operative time on graft survival after liver transplantation.

    Science.gov (United States)

    Lee, David D; Li, Jun; Wang, Guihua; Croome, Kristopher P; Burns, Justin M; Perry, Dana K; Nguyen, Justin H; Hopp, Wallace J; Taner, C Burcin

    2017-10-01

    Operative time often has been cited as an important factor for postoperative outcomes. Despite this belief, most efforts to improve liver transplant outcomes have largely focused on only patient and donor factors, and little attention has been paid on operative time. The primary objective of this project was to determine the impact of operative time on graft survival after liver transplant. A retrospective review of 2,877 consecutive liver transplants performed at a single institution was studied. Data regarding recipient, donor, and operative characteristics, including detailed granular operative times were collected prospectively and retrospectively reviewed. Using an instrument variable approach, Cox multivariate modeling was performed to assess the impact of operative time without the confounding of known and unknown variables. Of the 2,396 patients who met the criteria for review, the most important factors determining liver transplant graft survival included recipient history of Hepatitis C (hazard ratio 1.45, P = .02), donor age (hazard ratio 1.23, P = .03), use of liver graft from donation after cardiac death donor (hazard ratio 1.50, P operative time (hazard ratio 1.26, P = .01). In detailed analysis of stages of the liver transplant operation, the time interval from incision to anhepatic phase was associated with graft survival (hazard ratio 1.33; P = .02). Using a novel instrument variable approach, we demonstrate that operative time (in particular, the time interval from incision to anhepatic time) has a significant impact on graft survival. It also seems that some of this efficiency is under the influence of the transplant surgeon. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. The time dependent association of adrenaline administration and survival from out-of-hospital cardiac arrest.

    Science.gov (United States)

    Ewy, Gordon A; Bobrow, Bentley J; Chikani, Vatsal; Sanders, Arthur B; Otto, Charles W; Spaite, Daniel W; Kern, Karl B

    2015-11-01

    Recommended for decades, the therapeutic value of adrenaline (epinephrine) in the resuscitation of patients with out-of-hospital cardiac arrest (OHCA) is controversial. To investigate the possible time-dependent outcomes associated with adrenaline administration by Emergency Medical Services personnel (EMS). A retrospective analysis of prospectively collected data from a near statewide cardiac resuscitation database between 1 January 2005 and 30 November 2013. Multivariable logistic regression was used to analyze the effect of the time interval between EMS dispatch and the initial dose of adrenaline on survival. The primary endpoints were survival to hospital discharge and favourable neurologic outcome. Data from 3469 patients with witnessed OHCA were analyzed. Their mean age was 66.3 years and 69% were male. An initially shockable rhythm was present in 41.8% of patients. Based on a multivariable logistic regression model with initial adrenaline administration time interval (AATI) from EMS dispatch as the covariate, survival was greatest when adrenaline was administered very early but decreased rapidly with increasing (AATI); odds ratio 0.94 (95% Confidence Interval (CI) 0.92-0.97). The AATI had no significant effect on good neurological outcome (OR=0.96, 95% CI=0.90-1.02). In patients with OHCA, survival to hospital discharge was greater in those treated early with adrenaline by EMS especially in the subset of patients with a shockable rhythm. However survival rapidly decreased with increasing adrenaline administration time intervals (AATI). Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  19. The effect of time until surgical intervention on survival in dogs with secondary septic peritonitis.

    Science.gov (United States)

    Bush, Maxwell; Carno, Margaret A; St Germaine, Lindsay; Hoffmann, Daniel E

    2016-12-01

    This retrospective study examined the effect of time to intervention on outcome in cases of dogs with secondary septic peritonitis, and also searched for other potential prognostic factors. The medical records of 55 dogs were reviewed. No association was found between outcome and the time from hospital admission to surgical source control. However, several other factors were found to influence survival, including: age, needing vasopressors, lactate, pre-operative packed cell volume, serum alkaline phosphatase, serum total bilirubin, and post-operative serum albumin. These values were then used to create accurate pre- and post-operative survival prediction models.

  20. Random-effects regression analysis of correlated grouped-time survival data.

    Science.gov (United States)

    Hedeker, D; Siddiqui, O; Hu, F B

    2000-04-01

    Random-effects regression modelling is proposed for analysis of correlated grouped-time survival data. Two analysis approaches are considered. The first treats survival time as an ordinal outcome, which is either right-censored or not. The second approach treats survival time as a set of dichotomous indicators of whether the event occurred for time periods up to the period of the event or censor. For either approach both proportional hazards and proportional odds versions of the random-effects model are developed, while partial proportional hazards and odds generalizations are described for the latter approach. For estimation, a full-information maximum marginal likelihood solution is implemented using numerical quadrature to integrate over the distribution of multiple random effects. The quadrature solution allows some flexibility in the choice of distributions for the random effects; both normal and rectangular distributions are considered in this article. An analysis of a dataset where students are clustered within schools is used to illustrate features of random-effects analysis of clustered grouped-time survival data.

  1. The effect of time until surgical intervention on survival in dogs with secondary septic peritonitis

    OpenAIRE

    Bush, Maxwell; Carno, Margaret A.; St. Germaine, Lindsay; Hoffmann, Daniel E.

    2016-01-01

    This retrospective study examined the effect of time to intervention on outcome in cases of dogs with secondary septic peritonitis, and also searched for other potential prognostic factors. The medical records of 55 dogs were reviewed. No association was found between outcome and the time from hospital admission to surgical source control. However, several other factors were found to influence survival, including: age, needing vasopressors, lactate, pre-operative packed cell volume, serum alk...

  2. Effect of first cannulation time and dialysis machine blood flows on survival of arteriovenous fistulas.

    Science.gov (United States)

    Wilmink, Teun; Powers, Sarah; Hollingworth, Lee; Stevenson, Tamasin

    2017-10-16

    To study the effect of cannulation time on arteriovenous fistula (AVF) survival. Analysis of two prospective databases of access operations and dialysis sessions from 12 January 2002 through 4 January 2015 with follow-up until 4 January 2016. First cannulation time (FCT), defined from operation to first cannulation, was categorized as machine blood flow rate (BFR) for the first 29 dialysis sessions on AVF was analysed. Altogether, 1167 AVF with functional dialysis use were analysed: 667 (57%) radial cephalic AVF, 383 (33%) brachiocephalic AVF and 117 (10%) brachiobasilic AVF. The 631 (54%) AVF created in on-dialysis patients were analysed separately from 536 (46%) AVF created in pre-dialysis patients. AVF survival was similar between cannulation categories for both pre-dialysis patients (P = 0.19) and on-dialysis patients (P = 0.83). Early cannulation was associated with similar AVF survival in both pre-dialysis patients (P = 0.82) and on-dialysis patients (P = 0.17). Six consecutive successful cannulations from the start were associated with improved AVF survival (P = 0.0002). A below-median BFR at the start of dialysis was associated with better AVF survival (P machine BFR in the first week of dialysis are associated with decreased AVF survival.

  3. Two Artificial Neural Networks for Modeling Discrete Survival Time of Censored Data

    Directory of Open Access Journals (Sweden)

    Taysseer Sharaf

    2015-01-01

    Full Text Available Artificial neural network (ANN theory is emerging as an alternative to conventional statistical methods in modeling nonlinear functions. The popular Cox proportional hazard model falls short in modeling survival data with nonlinear behaviors. ANN is a good alternative to the Cox PH as the proportionality of the hazard assumption and model relaxations are not required. In addition, ANN possesses a powerful capability of handling complex nonlinear relations within the risk factors associated with survival time. In this study, we present a comprehensive comparison of two different approaches of utilizing ANN in modeling smooth conditional hazard probability function. We use real melanoma cancer data to illustrate the usefulness of the proposed ANN methods. We report some significant results in comparing the survival time of male and female melanoma patients.

  4. An approach to the drone fleet survivability assessment based on a stochastic continues-time model

    Science.gov (United States)

    Kharchenko, Vyacheslav; Fesenko, Herman; Doukas, Nikos

    2017-09-01

    An approach and the algorithm to the drone fleet survivability assessment based on a stochastic continues-time model are proposed. The input data are the number of the drones, the drone fleet redundancy coefficient, the drone stability and restoration rate, the limit deviation from the norms of the drone fleet recovery, the drone fleet operational availability coefficient, the probability of the drone failure-free operation, time needed for performing the required tasks by the drone fleet. The ways for improving the recoverable drone fleet survivability taking into account amazing factors of system accident are suggested. Dependencies of the drone fleet survivability rate both on the drone stability and the number of the drones are analysed.

  5. Measurement of Survival Time in Brachionus Rotifers: Synchronization of Maternal Conditions.

    Science.gov (United States)

    Kaneko, Gen; Yoshinaga, Tatsuki; Gribble, Kristin E; Welch, David M; Ushio, Hideki

    2016-07-22

    Rotifers are microscopic cosmopolitan zooplankton used as models in ecotoxicological and aging studies due to their several advantages such as short lifespan, ease of culture, and parthenogenesis that enables clonal culture. However, caution is required when measuring their survival time as it is affected by maternal age and maternal feeding conditions. Here we provide a protocol for powerful and reproducible measurement of the survival time in Brachionus rotifers following a careful synchronization of culture conditions over several generations. Empirically, poor synchronization results in early mortality and a gradual decrease in survival rate, thus resulting in weak statistical power. Indeed, under such conditions, calorie restriction (CR) failed to significantly extend the lifespan of B. plicatilis although CR-induced longevity has been demonstrated with well-synchronized rotifer samples in past and present studies. This protocol is probably useful for other invertebrate models, including the fruitfly Drosophila melanogaster and the nematode Caenorhabditis elegans, because maternal age effects have also been reported in these species.

  6. Effect of bifidobacteria implantation on the survival time of whole-body irradiated mice

    Energy Technology Data Exchange (ETDEWEB)

    Yokokura, T.; Onoue, M.; Mutai, M. (Yakult Institute for Microbiological Research)

    1980-01-01

    Letahl dose (2 KR) of gamma-ray was irradiated on the whole bodies of mice. Survival time after irradiation was significantly longer in mice with administration of both Bifidobacterium breve YIT 4008 and transgalactosyl oligosaccharide than in mice with administration of either of the two or nothing.

  7. It's Deja Vu All over Again: Using Multiple-Spell Discrete-Time Survival Analysis.

    Science.gov (United States)

    Willett, John B.; Singer, Judith D.

    1995-01-01

    The multiple-spell discrete-time survival analysis method is introduced and illustrated using longitudinal data on exit from and reentry into the teaching profession. The method is applicable to many educational problems involving the sequential occurrence of disparate events or episodes. (SLD)

  8. Recidivism and Survival Time: Racial Disparity among Jail Ex-Inmates

    Science.gov (United States)

    Jung, Hyunzee; Spjeldnes, Solveig; Yamatani, Hide

    2010-01-01

    Incarcerated men, most of whom are recidivists, are disproportionately black. Much literature about prison ex-inmates reports on this disparity, yet little is known about racial disparity in recidivism rates among jail ex-inmates. This study examined recidivism rates and survival time (period from release date to rearrest) among male ex-inmates…

  9. Palliative sedation in advanced cancer patients: Does it shorten survival time? - A systematic review

    Directory of Open Access Journals (Sweden)

    B Barathi

    2013-01-01

    Full Text Available Background: Patients with advanced cancer often suffer from multiple refractory symptoms in the terminal phase of their life. Palliative sedation is one of the few ways to relieve this refractory suffering. Objectives: This systematic review investigated the effect of palliative sedation on survival time in terminally ill cancer patients. Materials and Methods: Six electronic databases were searched for both prospective and retrospective studies which evaluated the effect of palliative sedation on survival time. Only those studies which had a comparison group that did not receive palliative sedation were selected for the review. Abstracts of all retrieved studies were screened to include the most relevant studies and only studies which met inclusion criteria were selected. References of all retrieved studies were also screened for relevant studies. Selected studies were assessed for quality and data extraction was done using the structured data extraction form. Results: Eleven studies including four prospective and seven retrospective studies were identified. Mean survival time (MST was measured as the time from last admission until death. A careful analysis of the results of all the 11 studies indicated that MST of sedated and non-sedated group was not statistically different in any of the studies. Conclusion: This systematic review supports the fact that palliative sedation does not shorten survival in terminally ill cancer patients. However, this conclusion needs to be taken with consideration of the methodology, study design, and the population studied of the included studies in this review.

  10. Graft pathology at the time of harvest: impact on long-term survival

    Directory of Open Access Journals (Sweden)

    Shi-Min Yuan

    2014-12-01

    Full Text Available Objective: This study aims to present the graft pathology at the time of harvest and its impact on long-term survival. Methods: The remnants of the bypass grafts from 66 consecutive patients with coronary artery disease receiving a coronary artery bypass grafting were investigated pathologically, and pertinent predictive risk factors and survival were analyzed. Results: Medial degenerative changes with or without intimal proliferation were present in 36.8%, 37.8% and 35.6% of left internal mammary artery (IMA, radial artery and saphenous vein grafts. There were 2 (3.0% hospital deaths and 9 (14.1% late deaths. Multinomial logistic regression revealed left IMA pathological changes, dyslipidemia, history of percutaneous transluminal coronary angioplasty/stent deployment and Y-graft were significant predictive risk factors negatively influencing the patients’ long-term survival. Kaplan-Meier survival analysis revealed that the long-term survival of patients with left IMA pathological changes were significantly reduced compared with those without (74.1% vs. 91.4%, P=0.002; whereas no differences were noted in long-term survivals between patients with and without pathological changes of the radial arterial or saphenous vein grafts. Conclusion: Pathological changes may be seen in the bypass graft at the time of harvest. The subtle ultrastructural modifications and the expressions of vascular tone regulators might be responsible for late graft patency. The pathological changes of the left IMA at the time of harvest rather than those of the radial artery or saphenous vein graft affect significantly longterm survival. Non-traumatic maneuver of left IMA harvest, well-controlled dyslipidemia and avoidance of using composite grafts can be helpful in maintaining the architecture of the grafts.

  11. Does prehospital time affect survival of major trauma patients where there is no prehospital care?

    Science.gov (United States)

    Dharap, S B; Kamath, S; Kumar, V

    2017-01-01

    Survival after major trauma is considered to be time dependent. Efficient prehospital care with rapid transport is the norm in developed countries, which is not available in many lower middle and low-income countries. The aim of this study was to assess the effect of prehospital time and primary treatment given on survival of major trauma patients in a setting without prehospital care. This prospective observational study was carried out in a university hospital in Mumbai, from January to December 2014. The hospital has a trauma service but no organized prehospital care or defined interhospital transfer protocols. All patients with life- and/or limb-threatening injuries were included in the study. Injury time and arrival time were noted and the interval was defined as "prehospital time" for the directly arriving patients and as "time to tertiary care" for those transferred. Primary outcome measure was in-hospital death (or discharge). Of 1181 patients, 352 were admitted directly from the trauma scene and 829 were transferred from other hospitals. In-hospital mortality was associated with age, mechanism and mode of injury, shock, Glasgow Coma Score prehospital time nor with time to tertiary care. Transferred patients had a significantly higher mortality (odds ratio = 1.869, 95% confidence interval = 1.233-2.561, P = 0.005) despite fewer patients with severe injury. Two hundred and ninety-four (35%) of these needed airway intervention while 108 (13%) needed chest tube insertion on arrival to the trauma unit suggesting inadequate care at primary facility. Mortality is not associated with prehospital time but with transfers from primary care; probably due to deficient care. To improve survival after major trauma, enhancement of resources for resuscitation and capacity building of on-duty doctors in primary centers should be a priority in countries with limited resources.

  12. The survival time of chocolates on hospital wards: covert observational study.

    Science.gov (United States)

    Gajendragadkar, Parag R; Moualed, Daniel J; Nicolson, Phillip L R; Adjei, Felicia D; Cakebread, Holly E; Duehmke, Rudolf M; Martin, Claire A

    2013-12-14

    To quantify the consumption of chocolates in a hospital ward environment. Multicentre, prospective, covert observational study. Four wards at three hospitals (where the authors worked) within the United Kingdom. Boxes of Quality Street (Nestlé) and Roses (Cadbury) on the ward and anyone eating these chocolates. Observers covertly placed two 350 g boxes of Quality Street and Roses chocolates on each ward (eight boxes were used in the study containing a total of 258 individual chocolates). These boxes were kept under continuous covert surveillance, with the time recorded when each chocolate was eaten. Median survival time of a chocolate. 191 out of 258 (74%) chocolates were observed being eaten. The mean total observation period was 254 minutes (95% confidence interval 179 to 329). The median survival time of a chocolate was 51 minutes (39 to 63). The model of chocolate consumption was non-linear, with an initial rapid rate of consumption that slowed with time. An exponential decay model best fitted these findings (model R(2)=0.844, Pchocolates to be eaten) of 99 minutes. The mean time taken to open a box of chocolates from first appearance on the ward was 12 minutes (95% confidence interval 0 to 24). Quality Street chocolates survived longer than Roses chocolates (hazard ratio for survival of Roses v Quality Street 0.70, 95% confidence interval 0.53 to 0.93, P=0.014). The highest percentages of chocolates were consumed by healthcare assistants (28%) and nurses (28%), followed by doctors (15%). From our observational study, chocolate survival in a hospital ward was relatively short, and was modelled well by an exponential decay model. Roses chocolates were preferentially consumed to Quality Street chocolates in a ward setting. Chocolates were consumed primarily by healthcare assistants and nurses, followed by doctors. Further practical studies are needed.

  13. Racial Disparities in Clinical Presentation and Survival Times Among Young-Onset Colorectal Adenocarcinoma.

    Science.gov (United States)

    Arshad, Hafiz Muhammad Sharjeel; Kabir, Christopher; Tetangco, Eula; Shah, Natahsa; Raddawi, Hareth

    2017-09-01

    Recently published data indicate increasing incidence of colorectal adenocarcinoma (CRC) in young-onset (racial disparities in presentation and survival times among non-Hispanic Blacks (NHB) and Hispanics compared with non-Hispanic Whites (NHW). A retrospective single-center cohort study was conducted from 2004 through 2014 using 96 patient medical charts with a diagnosis of young-onset CRC. Age, gender, primary site, and histological stage at the time of diagnosis were assessed for survival probabilities by racial group over a minimum follow-up period of 5 years. Among subjects with CRC diagnosis before 50 years of age, the majority of subjects were between 40 and 50 years, with CRC presentation occurring among this age group for 51 (79.7%) of NHW, 18 (81.8%) of NHB, and 5 (50.0%) of Hispanics. The majority of all patients presented with advanced stages of CRC (31.3% with stage III and 27.1% with stage IV). NHB exhibited statistically significantly worse survival compared to NHW (adjusted hazard ratio for death = 2.09; 95% confidence interval 1.14-3.84; P = 0.02). A possible trend of worse survival was identified for Hispanics compared to NHW, but this group was low in numbers and results were not statistically significant. Disparities between racial groups among young-onset CRC cases were identified in overall survival and reflect growing concern in rising incidence and differentiated care management.

  14. Multiparametric analysis of magnetic resonance images for glioma grading and patient survival time prediction

    Energy Technology Data Exchange (ETDEWEB)

    Garzon, Benjamin (Dept. of Circulation and Medical Imaging, NTNU, Trondheim (Norway)), email: benjamin.garzon@ntnu.no; Emblem, Kyrre E. (The Interventional Center, Rikshospitalet, Oslo Univ. Hospital, Oslo (Norway); Dept. of Radiology, MGH-HST AA Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston (United States)); Mouridsen, Kim (Center of Functionally Integrative Neuroscience, Aarhus Univ., Aarhus (Denmark)); Nedregaard, Baard; Due-Toennessen, Paulina; Nome, Terje; Hald, John K. (Dept. of Radiology and Nuclear Medicine, Rikshospitalet, Oslo Univ. Hospital, Oslo (Norway)); Bjoernerud, Atle (The Interventional Center, Rikshospitalet, Oslo Univ. Hospital, Oslo (Norway)); Haaberg, Asta K. (Dept. of Circulation and Medical Imaging, NTNU, Trondheim (Norway); Dept. of Medical Imaging, St Olav' s Hospital, Trondheim (Norway)); Kvinnsland, Yngve (NordicImagingLab, Bergen (Norway))

    2011-11-15

    Background. A systematic comparison of magnetic resonance imaging (MRI) options for glioma diagnosis is lacking. Purpose. To investigate multiple MR-derived image features with respect to diagnostic accuracy in tumor grading and survival prediction in glioma patients. Material and Methods. T1 pre- and post-contrast, T2 and dynamic susceptibility contrast scans of 74 glioma patients with histologically confirmed grade were acquired. For each patient, a set of statistical features was obtained from the parametric maps derived from the original images, in a region-of-interest encompassing the tumor volume. A forward stepwise selection procedure was used to find the best combinations of features for grade prediction with a cross-validated logistic model and survival time prediction with a cox proportional-hazards regression. Results. Presence/absence of enhancement paired with kurtosis of the FM (first moment of the first-pass curve) was the feature combination that best predicted tumor grade (grade II vs. grade III-IV; median AUC 0.96), with the main contribution being due to the first of the features. A lower predictive value (median AUC = 0.82) was obtained when grade IV tumors were excluded. Presence/absence of enhancement alone was the best predictor for survival time, and the regression was significant (P < 0.0001). Conclusion. Presence/absence of enhancement, reflecting transendothelial leakage, was the feature with highest predictive value for grade and survival time in glioma patients

  15. Evaluation of serum biochemical marker concentrations and survival time in dogs with protein-losing enteropathy.

    Science.gov (United States)

    Equilino, Mirjam; Théodoloz, Vincent; Gorgas, Daniela; Doherr, Marcus G; Heilmann, Romy M; Suchodolski, Jan S; Steiner, Jörg M; Burgener Dvm, Iwan A

    2015-01-01

    To evaluate serum concentrations of biochemical markers and survival time in dogs with protein-losing enteropathy (PLE). Prospective study. 29 dogs with PLE and 18 dogs with food-responsive diarrhea (FRD). Data regarding serum concentrations of various biochemical markers at the initial evaluation were available for 18 of the 29 dogs with PLE and compared with findings for dogs with FRD. Correlations between biochemical marker concentrations and survival time (interval between time of initial evaluation and death or euthanasia) for dogs with PLE were evaluated. Serum C-reactive protein concentration was high in 13 of 18 dogs with PLE and in 2 of 18 dogs with FRD. Serum concentration of canine pancreatic lipase immunoreactivity was high in 3 dogs with PLE but within the reference interval in all dogs with FRD. Serum α1-proteinase inhibitor concentration was less than the lower reference limit in 9 dogs with PLE and 1 dog with FRD. Compared with findings in dogs with FRD, values of those 3 variables in dogs with PLE were significantly different. Serum calprotectin (measured by radioimmunoassay and ELISA) and S100A12 concentrations were high but did not differ significantly between groups. Seventeen of the 29 dogs with PLE were euthanized owing to this disease; median survival time was 67 days (range, 2 to 2,551 days). Serum C-reactive protein, canine pancreatic lipase immunoreactivity, and α1-proteinase inhibitor concentrations differed significantly between dogs with PLE and FRD. Most initial biomarker concentrations were not predictive of survival time in dogs with PLE.

  16. Functional Status, Time to Transplantation, and Survival Benefit of Kidney Transplantation Among Wait-Listed Candidates

    Science.gov (United States)

    Reese, Peter P.; Shults, Justine; Bloom, Roy D.; Mussell, Adam; Harhay, Meera N.; Abt, Peter; Levine, Matthew; Johansen, Kirsten L.; Karlawish, Jason T.; Feldman, Harold I.

    2015-01-01

    Background In the context of an aging end-stage renal disease population with multiple comorbidities, transplantation professionals face challenges in evaluating the global health of patients awaiting kidney transplantation. Functional status might be useful for identifying which patients will derive a survival benefit from transplantation versus dialysis. Study Design Retrospective cohort study of wait-listed patients using data on functional status from a national dialysis provider linked to United Network for Organ Sharing registry data. Setting & Participants Adult kidney transplant candidates added to the waiting list between the years 2000 and 2006. Predictor Physical function scale of the Medical Outcomes Study 36-Item Short Form Healthy Survey, analyzed as a time-varying covariate. Outcomes Kidney transplantation; Survival benefit of transplantation versus remaining wait-listed. Measurements We used multivariable Cox regression to assess the association between physical function with study outcomes. In survival benefit analyses, transplant status was modeled as a time-varying covariate. Results The cohort comprised 19,242 kidney transplant candidates (median age, 51 years; 36% black race) receiving maintenance dialysis. Candidates in the lowest baseline physical function quartile were more likely to be inactivated (adjusted HR vs. highest quartile, 1.30; 95% CI, 1.21-1.39) and less likely to undergo transplantation (adjusted HR vs. highest quartile, 0.64; 95% CI, 0.61-0.68). After transplantation, worse physical function was associated with shorter 3-year survival (84% vs. 92% for the lowest vs. highest function quartiles). However, compared to dialysis, transplantation was associated with a statistically significant survival benefit by 9 months for patients in every function quartile. Limitations Functional status is self-reported. Conclusions Even patients with low function appear to live longer with kidney transplantation versus dialysis. For waitlisted

  17. Evaluation of Survival Time of Tooth Color Dental Materials in Primary Anterior Teeth

    Directory of Open Access Journals (Sweden)

    Behjat-Al-Molook Ajami

    2013-01-01

    Full Text Available Introduction: In restorative dentistry, selecting the proper material is an important factor for clinical success. The objective of this study was clinical evaluation of survival time of three tooth color materials in primary anterior teeth. Methods: In this interventional clinical trial study, 94 deciduous anterior teeth (36 teeth in boys, 58 teeth in girls belonging to 3-5 year old children in Pediatric Department of Mashhad Faculty of Dentistry, Iran were selected. Selective dental materials included compoglass, glass-ionomer Fuji II LC, and composite resin. The data were analyzed with Kaplan–Meyer and Log rank test. Results: compoglass had the highest survival time in comparison with composite and glass-ionomer. Nine months retention rate for teeth restored with compoglass, composite resin and glass-ionomer were estimated: 95%, 21%, and 12.5%, respectively. Conclusion: Compoglass can be a suitable material for anterior primary teeth restoration

  18. Mediation Analysis with Survival Outcomes: Accelerated Failure Time Versus Proportional Hazards Models

    Directory of Open Access Journals (Sweden)

    Lois A Gelfand

    2016-03-01

    Full Text Available Objective: Survival time is an important type of outcome variable in treatment research. Currently, limited guidance is available regarding performing mediation analyses with survival outcomes, which generally do not have normally distributed errors, and contain unobserved (censored events. We present considerations for choosing an approach, using a comparison of semi-parametric proportional hazards (PH and fully parametric accelerated failure time (AFT approaches for illustration.Method: We compare PH and AFT models and procedures in their integration into mediation models and review their ability to produce coefficients that estimate causal effects. Using simulation studies modeling Weibull-distributed survival times, we compare statistical properties of mediation analyses incorporating PH and AFT approaches (employing SAS procedures PHREG and LIFEREG, respectively under varied data conditions, some including censoring. A simulated data set illustrates the findings.Results: AFT models integrate more easily than PH models into mediation models. Furthermore, mediation analyses incorporating LIFEREG produce coefficients that can estimate causal effects, and demonstrate superior statistical properties. Censoring introduces bias in the coefficient estimate representing the treatment effect on outcome – underestimation in LIFEREG, and overestimation in PHREG. With LIFEREG, this bias can be addressed using an alternative estimate obtained from combining other coefficients, whereas this is not possible with PHREG.Conclusions: When Weibull assumptions are not violated, there are compelling advantages to using LIFEREG over PHREG for mediation analyses involving survival-time outcomes. Irrespective of the procedures used, the interpretation of coefficients, effects of censoring on coefficient estimates, and statistical properties should be taken into account when reporting results.

  19. Determination of the impact of melanoma surgical timing on survival using the National Cancer Database.

    Science.gov (United States)

    Conic, Ruzica Z; Cabrera, Claudia I; Khorana, Alok A; Gastman, Brian R

    2018-01-01

    The ideal timing for melanoma treatment, predominantly surgery, remains undetermined. Patient concern for receiving immediate treatment often exceeds surgeon or hospital availability, requiring establishment of a safe window for melanoma surgery. To assess the impact of time to definitive melanoma surgery on overall survival. Patients with stage I to III cutaneous melanoma and with available time to definitive surgery and overall survival were identified by using the National Cancer Database (N = 153,218). The t test and chi-square test were used to compare variables. Cox regression was used for multivariate analysis. In a multivariate analysis of patients in all stages who were treated between 90 and 119 days after biopsy (hazard ratio [HR], 1.09; 95% confidence interval [CI], 1.01-1.18) and more than 119 days (HR, 1.12; 95% CI, 1.02-1.22) had a higher risk for mortality compared with those treated within 30 days of biopsy. In a subgroup analysis of stage I, higher mortality risk was found in patients treated within 30 to 59 days (HR, 1.05; 95% CI, 1.01-1.1), 60 to 89 days (HR, 1.16; 95% CI, 1.07-1.25), 90 to 119 days (HR, 1.29; 95% CI, 1.12-1.48), and more than 119 days after biopsy (HR, 1.41; 95% CI, 1.21-1.65). Surgical timing did not affect survival in stages II and III. Melanoma-specific survival was not available. Expeditious treatment of stage I melanoma is associated with improved outcomes. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  20. Correlation between Pulmonary Function Indexes and Survival Time 
in Patients with Advanced Lung Cancer

    OpenAIRE

    Ge, Hui; Jiang, Zhenghua; Huang, Qian; Muyun ZHU; Yang, Jie

    2013-01-01

    Background and objective To those patients with advanced lung cancer, the ultimate objective is to improve the curative effect and quality of life, lung function indexes are an important factor. We investigate the change of lung function and the relationship between pulmonary function indexs and survival time in patients with advanced lung cancer. Methods Lung function was detected in 59 cases with lung cancer and 63 normal controls. The relationship between pulmonary function indexs and surv...

  1. Time-Dependent Tree-Structured Survival Analysis with Unbiased Variable Selection through Permutation Tests

    Science.gov (United States)

    Wallace, M. L.

    2014-01-01

    Incorporating time-dependent covariates into tree-structured survival analysis (TSSA) may result in more accurate prognostic models than if only baseline values are used. Available time-dependent TSSA methods exhaustively test every binary split on every covariate; however, this approach may result in selection bias towards covariates with more observed values. We present a method that uses unbiased significance levels from newly proposed permutation tests to select the time-dependent or baseline covariate with the strongest relationship with the survival outcome. The specific splitting value is identified using only the selected covariate. Simulation results show that the proposed time-dependent TSSA method produces tree models of equal or greater accuracy as compared to baseline TSSA models, even with high censoring rates and large within-subject variability in the time-dependent covariate. To illustrate, the proposed method is applied to data from a cohort of bipolar youth to identify subgroups at risk for self-injurious behavior. PMID:25043382

  2. Impact of Treatment Time on the Survival of Patients Suffering from Invasive Fungal Rhinosinusitis

    Directory of Open Access Journals (Sweden)

    Patorn Piromchai

    2014-01-01

    Full Text Available Background Invasive fungal rhinosinusitis is an uncommon disease with high mortality rates. There is currently no consensus on the best treatment timing. We studied the impact of the treatment timing on the survival of patients experiencing invasive fungal rhinosinusitis. Methods We conducted a retrospective study of patients suffering from invasive fungal rhinosinusitis. The duration of symptoms, clinical presentations, clinical signs, diagnoses, treatments, and outcomes were collected. Results It was observed that more than 70% of the mortalities occurred within the subgroup of patients who exhibited symptoms of the disease within 14 days before admission. After adjusting for the confounders, the time taken to treat the patients was the most statistically significant predictor for mortality ( P = 0.045. We found no significant relationships between mortality and its significant covariates, which included the underlying diseases ( P = 0.91 or complications ( P = 0.55. Conclusions Our study demonstrates that the time taken to treat the patients is an important determinant for the survival of patients who are afflicted with invasive fungal rhinosinusitis. The appropriate treatments should be administered within 14 days from the time the symptoms begin to manifest.

  3. Impact of treatment time on the survival of patients suffering from invasive fungal rhinosinusitis.

    Science.gov (United States)

    Piromchai, Patorn; Thanaviratananich, Sanguansak

    2014-01-01

    Invasive fungal rhinosinusitis is an uncommon disease with high mortality rates. There is currently no consensus on the best treatment timing. We studied the impact of the treatment timing on the survival of patients experiencing invasive fungal rhinosinusitis. We conducted a retrospective study of patients suffering from invasive fungal rhinosinusitis. The duration of symptoms, clinical presentations, clinical signs, diagnoses, treatments, and outcomes were collected. It was observed that more than 70% of the mortalities occurred within the subgroup of patients who exhibited symptoms of the disease within 14 days before admission. After adjusting for the confounders, the time taken to treat the patients was the most statistically significant predictor for mortality (P = 0.045). We found no significant relationships between mortality and its significant covariates, which included the underlying diseases (P = 0.91) or complications (P = 0.55). Our study demonstrates that the time taken to treat the patients is an important determinant for the survival of patients who are afflicted with invasive fungal rhinosinusitis. The appropriate treatments should be administered within 14 days from the time the symptoms begin to manifest.

  4. Tumor Cells Growth and Survival Time with the Ketogenic Diet in Animal Models: A Systematic Review.

    Science.gov (United States)

    Khodadadi, Soheila; Sobhani, Nafiseh; Mirshekar, Somaye; Ghiasvand, Reza; Pourmasoumi, Makan; Miraghajani, Maryam; Dehsoukhteh, Somayeh Shahraki

    2017-01-01

    Recently, interest in targeted cancer therapies via metabolic pathways has been renewed with the discovery that many tumors become dependent on glucose uptake during anaerobic glycolysis. Also the inability of ketone bodies metabolization due to various deficiencies in mitochondrial enzymes is the major metabolic changes discovered in malignant cells. Therefore, administration of a ketogenic diet (KD) which is based on high in fat and low in carbohydrates might inhibit tumor growth and provide a rationale for therapeutic strategies. So, we conducted this systematic review to assess the effects of KD on the tumor cells growth and survival time in animal studies. All databases were searched from inception to November 2015. We systematically searched the PubMed, Scopus, Google Scholars, Science Direct and Cochrane Library according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. To assess the quality of included studies we used SYRCLE's RoB tool. 268 articles were obtained from databases by primary search. Only 13 studies were eligible according to inclusion criteria. From included studies, 9 articles indicate that KD had a beneficial effect on tumor growth and survival time. Tumor types were included pancreatic, prostate, gastric, colon, brain, neuroblastoma and lung cancers. In conclusions, although studies in this field are rare and inconsistence, recent findings have demonstrated that KD can potentially inhibit the malignant cell growth and increase the survival time. Because of differences physiology between animals and humans, future studies in cancer patients treated with a KD are needed.

  5. Tumor cells growth and survival time with the ketogenic diet in animal models: A systematic review

    Directory of Open Access Journals (Sweden)

    Soheila Khodadadi

    2017-01-01

    Full Text Available Recently, interest in targeted cancer therapies via metabolic pathways has been renewed with the discovery that many tumors become dependent on glucose uptake during anaerobic glycolysis. Also the inability of ketone bodies metabolization due to various deficiencies in mitochondrial enzymes is the major metabolic changes discovered in malignant cells. Therefore, administration of a ketogenic diet (KD which is based on high in fat and low in carbohydrates might inhibit tumor growth and provide a rationale for therapeutic strategies. So, we conducted this systematic review to assess the effects of KD on the tumor cells growth and survival time in animal studies. All databases were searched from inception to November 2015. We systematically searched the PubMed, Scopus, Google Scholars, Science Direct and Cochrane Library according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. To assess the quality of included studies we used SYRCLE's RoB tool. 268 articles were obtained from databases by primary search. Only 13 studies were eligible according to inclusion criteria. From included studies, 9 articles indicate that KD had a beneficial effect on tumor growth and survival time. Tumor types were included pancreatic, prostate, gastric, colon, brain, neuroblastoma and lung cancers. In conclusions, although studies in this field are rare and inconsistence, recent findings have demonstrated that KD can potentially inhibit the malignant cell growth and increase the survival time. Because of differences physiology between animals and humans, future studies in cancer patients treated with a KD are needed.

  6. Cancer patient survival in Estonia 1995-2009: time trends and data quality.

    Science.gov (United States)

    Innos, K; Baburin, A; Aareleid, T

    2014-06-01

    Survival from most cancers in Estonia has been consistently below European average. The objective of this study was to examine recent survival trends in Estonia and to quantify the effect on survival estimates of the temporary disruption of the Estonian Cancer Registry (ECR) practices in 2001-2007 when death certificates could not be used for case ascertainment. ECR data on all adult cases of 16 common cancers diagnosed in Estonia during 1995-2008 and followed up for vital status until 2009 were used to estimate relative survival ratios (RSR). We used cohort analysis for patients diagnosed in 1995-1999 and 2000-2004; and period hybrid approach to obtain the most recent estimates (2005-2009). We compared five-year RSRs calculated from data sets with and without death certificate initiated (DCI) cases. A total of 64328 cancer cases were included in survival analysis. Compared with 1995-1999, five-year age-standardized RSR increased 20 percent units for prostate cancer, reaching 76% in 2005-2009. A rise of 10 percent units or more was also seen for non-Hodgkin lymphoma (five-year RSR 51% in 2005-2009), and cancers of rectum (49%), breast (73%) and ovary (37%). The effect of including/excluding DCI cases from survival analysis was small except for lung and pancreatic cancers. Relative survival continued to increase in Estonia during the first decade of the 21st century, although for many cancers, a gap between Estonia and more affluent countries still exists. Cancer control efforts should aim at the reduction of risk factors amenable to primary prevention, but also at the improvement of early diagnosis and ensuring timely and optimal care to all cancer patients. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Association of the Timing of Pregnancy With Survival in Women With Breast Cancer.

    Science.gov (United States)

    Iqbal, Javaid; Amir, Eitan; Rochon, Paula A; Giannakeas, Vasily; Sun, Ping; Narod, Steven A

    2017-05-01

    Increasing numbers of women experience pregnancy around the time of, or after, a diagnosis of breast cancer. Understanding the effect of pregnancy on survival in women with breast cancer will help in the counseling and treatment of these women. To compare the overall survival of women diagnosed with breast cancer during pregnancy or in the postpartum period with that of women who had breast cancer but did not become pregnant. This population-based, retrospective cohort study linked health administrative databases in Ontario, Canada, comprising 7553 women aged 20 to 45 years at the time of diagnosis with invasive breast cancer, from January 1, 2003, to December 31, 2014. Any pregnancy in the period from 5 years before, until 5 years after, the index date of the diagnosis of breast cancer. Women were classified into the following 4 exposure groups: no pregnancy (the referent), pregnancy before breast cancer, pregnancy-associated breast cancer, and pregnancy following breast cancer. Five-year actuarial survival rates for all exposure groups, age-adjusted and multivariable hazard ratios [HRs] of pregnancy for overall survival for all exposure groups, and time-dependent hazard ratios for women with pregnancy following breast cancer. Among the 7553 women in the study (mean age at diagnosis, 39.1 years; median, 40 years; range, 20-44 years) the 5-year actuarial survival rate was 87.5% (95% CI, 86.5%-88.4%) for women with no pregnancy, 85.3% (95% CI, 82.8%-87.8%) for women with pregnancy before breast cancer (age-adjusted hazard ratio, 1.03; 95% CI, 0.85-1.27; P = .73), and 82.1% (95% CI, 78.3%-85.9%) for women with pregnancy-associated breast cancer (age-adjusted hazard ratio, 1.18; 95% CI, 0.91-1.53; P = .20). The 5-year actuarial survival rate was 96.7% (95% CI, 94.1%-99.3%) for women who had pregnancy 6 months or more after diagnosis of breast cancer, vs 87.5% (95% CI, 86.5%-88.4%) for women with no pregnancy) (age-adjusted HR, 0.22; 95% CI, 0.10-0.49; P

  8. Survival times with and without tube feeding in patients with dementia or psychiatric diseases in Japan.

    Science.gov (United States)

    Takayama, Keiko; Hirayama, Keisuke; Hirao, Akihiko; Kondo, Keiko; Hayashi, Hideki; Kadota, Koichi; Asaba, Hiroyuki; Ishizu, Hideki; Nakata, Kenji; Kurisu, Kairi; Oshima, Etsuko; Yokota, Osamu; Yamada, Norihito; Terada, Seishi

    2017-11-01

    It is widely supposed that there has been no evidence of increased survival in patients with advanced dementia receiving enteral tube feeding. However, more than a few studies have reported no harmful outcome from tube feeding in dementia patients compared to in patients without dementia. This was a retrospective study. Nine psychiatric hospitals in Okayama Prefecture participated in this survey. All inpatients fulfilling the entry criteria were evaluated. All subjects suffered from difficulty with oral intake. Attending physicians thought that the patients could not live without long-term artificial nutrition. The physicians decided whether to make use of long-term artificial nutrition between January 2012 and December 2014. We evaluated 185 patients. Their mean age was 76.6 ± 11.4 years. Of all subjects, patients with probable Alzheimer's disease (n = 78) formed the biggest group, schizophrenia patients (n = 44) the second, and those with vascular dementia (n = 30) the third. The median survival times were 711 days for patients with tube feeding and 61 days for patients without tube feeding. In a comparison different types of tube feeding, median survival times were 611 days for patients with a nasogastric tube and more than 1000 days for those with a percutaneous endoscopic gastrostomy tube. Patients with tube feeding survived longer than those without tube feeding, even among dementia patients. This study suggests that enteral nutrition for patients with dementia prolongs survival. Additionally, percutaneous endoscopic gastrostomy tube feeding may be safer than nasogastric tube feeding among patients in psychiatric hospitals. © 2017 Japanese Psychogeriatric Society.

  9. Integrated survival analysis using an event-time approach in a Bayesian framework

    Science.gov (United States)

    Walsh, Daniel P.; Dreitz, VJ; Heisey, Dennis M.

    2015-01-01

    Event-time or continuous-time statistical approaches have been applied throughout the biostatistical literature and have led to numerous scientific advances. However, these techniques have traditionally relied on knowing failure times. This has limited application of these analyses, particularly, within the ecological field where fates of marked animals may be unknown. To address these limitations, we developed an integrated approach within a Bayesian framework to estimate hazard rates in the face of unknown fates. We combine failure/survival times from individuals whose fates are known and times of which are interval-censored with information from those whose fates are unknown, and model the process of detecting animals with unknown fates. This provides the foundation for our integrated model and permits necessary parameter estimation. We provide the Bayesian model, its derivation, and use simulation techniques to investigate the properties and performance of our approach under several scenarios. Lastly, we apply our estimation technique using a piece-wise constant hazard function to investigate the effects of year, age, chick size and sex, sex of the tending adult, and nesting habitat on mortality hazard rates of the endangered mountain plover (Charadrius montanus) chicks. Traditional models were inappropriate for this analysis because fates of some individual chicks were unknown due to failed radio transmitters. Simulations revealed biases of posterior mean estimates were minimal (≤ 4.95%), and posterior distributions behaved as expected with RMSE of the estimates decreasing as sample sizes, detection probability, and survival increased. We determined mortality hazard rates for plover chicks were highest at weights and/or whose nest was within agricultural habitats. Based on its performance, our approach greatly expands the range of problems for which event-time analyses can be used by eliminating the need for having completely known fate data.

  10. Timing of adjuvant chemotherapy and its relation to survival among patients with stage III colon cancer.

    Science.gov (United States)

    Bos, A C R K; van Erning, F N; van Gestel, Y R B M; Creemers, G J M; Punt, C J A; van Oijen, M G H; Lemmens, V E P P

    2015-11-01

    Currently available data suggest that delaying the start of adjuvant chemotherapy in colon cancer patients has a detrimental effect on survival. We analysed which factors impact on the timing of adjuvant chemotherapy and evaluated the influence on overall survival (OS). Stage III colon cancer patients who underwent resection and received adjuvant chemotherapy between 2008 and 2013 were selected from the Netherlands Cancer Registry. Timing of adjuvant chemotherapy was subdivided into: ⩽ 4, 5-6, 7-8, 9-10, 11-12 and 13-16 weeks post-surgery. Multivariable regressions were performed to assess the influence of several factors on the probability of starting treatment within 8 weeks post-surgery and to evaluate the association of timing of adjuvant chemotherapy with 5-year OS. 6620 patients received adjuvant chemotherapy, 14% commenced after 8 weeks. Factors associated with starting treatment after 8 weeks were older age (Odds ratio (OR) 65-74 versus colon cancer patients within 8 weeks post-surgery. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Survival Times of Meter-Sized Rock Boulders on the Surface of Airless Bodies

    Science.gov (United States)

    Basilevsky, A. T.; Head, J. W.; Horz, F.; Ramsley, K.

    2015-01-01

    This study considers the survival times of meter-sized rock boulders on the surfaces of several airless bodies. As the starting point, we employ estimates of the survival times of such boulders on the surface of the Moon by[1], then discuss the role of destruction due to day-night temperature cycling, consider the meteorite bombardment environment on the considered bodies in terms of projectile flux and velocities and finally estimate the survival times. Survival times of meter-sized rocks on lunar surface: The survival times of hand specimen-sized rocks exposed to the lunar surface environment were estimated based on experiments modeling the destruction of rocks by meteorite impacts, combined with measurements of the lunar surface meteorite flux, (e.g.,[2]). For estimations of the survival times of meter-sized lunar boulders, [1] suggested a different approach based on analysis of the spatial density of boulders on the rims of small lunar craters of known absolute age. It was found that for a few million years, only a small fraction of the boulders ejected by cratering process are destroyed, for several tens of million years approx.50% are destroyed, and for 200-300 Ma, 90 to 99% are destroyed. Following [2] and other works, [1] considered that the rocks are mostly destroyed by meteorite impacts. Destruction of rocks by thermal-stress. However, high diurnal temperature variations on the surface of the Moon and other airless bodies imply that thermal stresses may also be a cause of surface rock destruction. Delbo et al. [3] interpreted the observed presence of fine debris on the surface of small asteroids as due to thermal surface cycling. They stated that because of the very low gravity on the surface of these bodies, ejecta from meteorite impacts should leave the body, so formation there of fine debris has to be due to thermal cycling. Based on experiments on heating-cooling of cm-scale pieces of ordinary and carbonaceous chondrites and theoretical modeling of

  12. Functional status, time to transplantation, and survival benefit of kidney transplantation among wait-listed candidates.

    Science.gov (United States)

    Reese, Peter P; Shults, Justine; Bloom, Roy D; Mussell, Adam; Harhay, Meera N; Abt, Peter; Levine, Matthew; Johansen, Kirsten L; Karlawish, Jason T; Feldman, Harold I

    2015-11-01

    In the context of an aging end-stage renal disease population with multiple comorbid conditions, transplantation professionals face challenges in evaluating the global health of patients awaiting kidney transplantation. Functional status might be useful for identifying which patients will derive a survival benefit from transplantation versus dialysis. Retrospective cohort study of wait-listed patients using data for functional status from a national dialysis provider linked to United Network for Organ Sharing registry data. Adult kidney transplantation candidates added to the waiting list between 2000 and 2006. Physical Functioning scale of the Medical Outcomes Study 36-Item Short Form Health Survey, analyzed as a time-varying covariate. Kidney transplantation; survival benefit of transplantation versus remaining wait-listed. We used multivariable Cox regression to assess the association between physical function with study outcomes. In survival benefit analyses, transplantation status was modeled as a time-varying covariate. The cohort comprised 19,242 kidney transplantation candidates (median age, 51 years; 36% black race) receiving maintenance dialysis. Candidates in the lowest baseline Physical Functioning score quartile were more likely to be inactivated (adjusted HR vs highest quartile, 1.30; 95% CI, 1.21-1.39) and less likely to undergo transplantation (adjusted HR vs highest quartile, 0.64; 95% CI, 0.61-0.68). After transplantation, worse Physical Functioning score was associated with shorter 3-year survival (84% vs 92% for the lowest vs highest function quartiles). However, compared to dialysis, transplantation was associated with a statistically significant survival benefit by 9 months for patients in every function quartile. Functional status is self-reported. Even patients with low function appear to live longer with kidney transplantation versus dialysis. For wait-listed patients, global health measures such as functional status may be more useful in

  13. Survival time of dogs with splenic hemangiosarcoma treated by splenectomy with or without adjuvant chemotherapy: 208 cases (2001-2012).

    Science.gov (United States)

    Wendelburg, Kristin M; Price, Lori Lyn; Burgess, Kristine E; Lyons, Jeremiah A; Lew, Felicia H; Berg, John

    2015-08-15

    To determine survival time for dogs with splenic hemangiosarcoma treated with splenectomy alone, identify potential prognostic factors, and evaluate the efficacy of adjuvant chemotherapy. Retrospective case series. 208 dogs. Medical records were reviewed, long-term follow-up information was obtained, and survival data were analyzed statistically. 154 dogs were treated with surgery alone, and 54 were treated with surgery and chemotherapy. Twenty-eight dogs received conventional chemotherapy, 13 received cyclophosphamide-based metronomic chemotherapy, and 13 received both conventional and metronomic chemotherapy. Median survival time of dogs treated with splenectomy alone was 1.6 months. Clinical stage was the only prognostic factor significantly associated with survival time. When the entire follow-up period was considered, there was no significant difference in survival time between dogs treated with surgery alone and dogs treated with surgery and chemotherapy. However, during the first 4 months of follow-up, after adjusting for the effects of clinical stage, survival time was significantly prolonged among dogs receiving any type of chemotherapy (hazard ratio, 0.6) and among dogs receiving both conventional and metronomic chemotherapy (hazard ratio, 0.4). Clinical stage was strongly associated with prognosis for dogs with splenic hemangiosarcoma. Chemotherapy was effective in prolonging survival time during the early portion of the follow-up period. Combinations of doxorubicin-based conventional protocols and cyclophosphamide-based metronomic protocols appeared to be more effective than either type of chemotherapy alone, but prolongations in survival time resulting from current protocols were modest.

  14. Molecular clock evidence for survival of Antarctic cyanobacteria (Oscillatoriales, Phormidium autumnale) from Paleozoic times.

    Science.gov (United States)

    Strunecký, Otakar; Elster, Josef; Komárek, Jiří

    2012-11-01

    Cyanobacteria are well adapted to freezing and desiccation; they have been proposed as possible survivors of comprehensive Antarctic glaciations. Filamentous types from the order Oscillatoriales, especially the species Phormidium autumnale Kützing ex Gomont 1892, have widely diverse morphotypes that dominate in Antarctic aquatic microbial mats, seepages, and wet soils. Currently little is known about the dispersion of cyanobacteria in Antarctica and of their population history. We tested the hypothesis that cyanobacteria survived Antarctic glaciations directly on site after the Gondwana breakup by using the relaxed and strict molecular clock in the analysis of the 16S rRNA gene. We estimated that the biogeographic history of Antarctic cyanobacteria belonging to P. autumnale lineages has ancient origins. The oldest go further back in time than the breakup of Gondwana and originated somewhere on the supercontinent between 442 and 297 Ma. Enhanced speciation rate was found around the time of the opening of the Drake Passage (c. 31-45 Ma) with beginning of glaciations (c. 43 Ma). Our results, based primarily on the strains collected in maritime Antarctica, mostly around James Ross Island, support the hypothesis that long-term survival took place in glacial refuges. The high morphological diversification of P. autumnale suggested the coevolution of lineages and formation of complex associations with different morphologies, resulting in a specific endemic Antarctic cyanobacterial flora. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  15. Time-Varying Effects of Prognostic Factors Associated With Disease-Free Survival in Breast Cancer

    Science.gov (United States)

    Natarajan, Loki; Pu, Minya; Parker, Barbara A.; Thomson, Cynthia A.; Caan, Bette J.; Flatt, Shirley W.; Madlensky, Lisa; Hajek, Richard A.; Al-Delaimy, Wael K.; Saquib, Nazmus; Gold, Ellen B.

    2009-01-01

    Early detection and effective treatments have dramatically improved breast cancer survivorship, yet the risk of relapse persists even 15 years after the initial diagnosis. It is important to identify prognostic factors for late breast cancer events. The authors investigated time-varying effects of tumor characteristics on breast-cancer-free survival using data on 3,088 breast cancer survivors from 4 US states who participated in a randomized dietary intervention trial in 1995–2006, with maximum follow-up through 15 years (median, 9 years). A piecewise constant penalized spline approach incorporating time-varying coefficients was adopted, allowing for deviations from the proportional hazards assumption. This method is more flexible than standard approaches, provides direct estimates of hazard ratios across time intervals, and is computationally tractable. Having a stage II or III tumor was associated with a 3-fold higher hazard of breast cancer than having a stage I tumor during the first 2.5 years after diagnosis; this hazard ratio decreased to 2.1 after 7.7 years, but higher tumor stage remained a significant risk factor. Similar diminishing effects were found for poorly differentiated tumors. Interestingly, having a positive estrogen receptor status was protective up to 4 years after diagnosis but detrimental after 7.7 years (hazard ratio = 1.5). These results emphasize the importance of careful statistical modeling allowing for possibly time-dependent effects in long-term survivorship studies. PMID:19403844

  16. Adjuvant Radiation Therapy Treatment Time Impacts Overall Survival in Gastric Cancer

    Energy Technology Data Exchange (ETDEWEB)

    McMillan, Matthew T. [Department of Radiation Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Ojerholm, Eric [Department of Radiation Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Roses, Robert E., E-mail: Robert.Roses@uphs.upenn.edu [Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Plastaras, John P.; Metz, James M. [Department of Radiation Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Mamtani, Ronac [Department of Hematology/Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Karakousis, Giorgos C.; Fraker, Douglas L.; Drebin, Jeffrey A. [Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Stripp, Diana; Ben-Josef, Edgar [Department of Radiation Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Datta, Jashodeep [Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States)

    2015-10-01

    Purpose: Prolonged radiation therapy treatment time (RTT) is associated with worse survival in several tumor types. This study investigated whether delays during adjuvant radiation therapy impact overall survival (OS) in gastric cancer. Methods and Materials: The National Cancer Data Base was queried for patients with resected gastric cancer who received adjuvant radiation therapy with National Comprehensive Cancer Network–recommended doses (45 or 50.4 Gy) between 1998 and 2006. RTT was classified as standard (45 Gy: 33-36 days, 50.4 Gy: 38-41 days) or prolonged (45 Gy: >36 days, 50.4 Gy: >41 days). Cox proportional hazards models evaluated the association between the following factors and OS: RTT, interval from surgery to radiation therapy initiation, interval from surgery to radiation therapy completion, radiation therapy dose, demographic/pathologic and operative factors, and other elements of adjuvant multimodality therapy. Results: Of 1591 patients, RTT was delayed in 732 (46%). Factors associated with prolonged RTT were non-private health insurance (OR 1.3, P=.005) and treatment at non-academic facilities (OR 1.2, P=.045). Median OS and 5-year actuarial survival were significantly worse in patients with prolonged RTT compared with standard RTT (36 vs 51 months, P=.001; 39 vs 47%, P=.005); OS worsened with each cumulative week of delay (P<.0004). On multivariable analysis, prolonged RTT was associated with inferior OS (hazard ratio 1.2, P=.002); the intervals from surgery to radiation therapy initiation or completion were not. Prolonged RTT was particularly detrimental in patients with node positivity, inadequate nodal staging (<15 nodes examined), and those undergoing a cycle of chemotherapy before chemoradiation therapy. Conclusions: Delays during adjuvant radiation therapy appear to negatively impact survival in gastric cancer. Efforts to minimize cumulative interruptions to <7 days should be considered.

  17. Association of bystander cardiopulmonary resuscitation and survival according to ambulance response-times after out-of-hospital cardiac arrest

    DEFF Research Database (Denmark)

    Rajan, Shahzleen; Wissenberg, Mads; Folke, Fredrik

    2016-01-01

    Background: Bystander-initiated cardiopulmonary resuscitation (CPR) increases patient survival after out-of-hospital cardiac arrest, but it is unknown to what degree bystander CPR remains positively associated with survival with increasing time to potential defibrillation. The main objective...... was to examine the association of bystander CPR with survival as time to advanced treatment increases. Methods: We studied 7623 out-of-hospital cardiac arrest patients between 2005 and 2011, identified through the nationwide Danish Cardiac Arrest Registry. Multiple logistic regression analysis was used...... out-of-hospital cardiac arrest statistics, an additional 233 patients could potentially be saved annually if response time was reduced from 10 to 5 minutes and 119 patients if response time was reduced from 7 (the median response time in this study) to 5 minutes. Conclusions: The absolute survival...

  18. Analysis of multilevel grouped survival data with time-varying regression coefficients.

    Science.gov (United States)

    Wong, May C M; Lam, K F; Lo, Edward C M

    2011-02-10

    Correlated or multilevel grouped survival data are common in medical and dental research. Two common approaches to analyze such data are the marginal and the random-effects approaches. Models and methods in the literature generally assume that the treatment effect is constant over time. A researcher may be interested in studying whether the treatment effects in a clinical trial vary over time, say fade out gradually. This is of particular clinical value when studying the long-term effect of a treatment. This paper proposed to extend the random effects grouped proportional hazards models by incorporating the possibly time-varying covariate effects into the model in terms of a state-space formulation. The proposed model is very flexible and the estimation can be performed using the MCMC approach with non-informative priors in the Bayesian framework. The method is applied to a data set from a prospective clinical trial investigating the effectiveness of silver diamine fluoride (SDF) and sodium fluoride (NaF) varnish in arresting active dentin caries in the Chinese preschool children. It is shown that the treatment groups with caries removal prior to the topical fluoride applications are most effective in shortening the arrest times in the first 6-month interval, but their effects fade out rapidly since then. The effects of treatment groups without caries removal prior to topical fluoride application drop at a very slow rate and can be considered as more or less constant over time. The applications of SDF solution is found to be more effective than the applications of NaF vanish. Copyright © 2010 John Wiley & Sons, Ltd.

  19. Splenectomy increases the survival time of heart allograft via developing immune tolerance

    Science.gov (United States)

    2013-01-01

    Background The spleen is an active lymphoid organ. The effect of splenectomy on the immune response remains unclear. This study investigated whether splenectomy can induce immune tolerance and has a beneficial role in cardiac allograft. Methods Wistar rats were used for heart donors. The Sprague–Dawley (SD) rats designated as the recipients of heart transplantation (HT) were randomly assigned into four groups: sham, splenectomy, HT, splenectomy + HT. The survival of transplanted hearts was assessed by daily checking of abdominal palpation. At various time points after transplantation, the transplanted hearts were collected and histologically examined; the level of CD4+CD25+ T regulatory lymphocytes (Tregs) and rate of lymphocyte apoptosis (annexin-v+ PI+ cells) in the blood were analyzed by using flow cytometric method. Results 1) Splenectomy significantly prolonged the mean survival time of heart allografts (7 ± 1.1 days and 27 ± 1.5 days for HT and splenectomy + HT, respectively; n = 12-14/group, HT vs. splenectomy + HT, p Splenectomy delayed pathological changes (inflammatory cell infiltration, myocardial damage) of the transplanted hearts in splenectomy + HT rats; 3) The level of CD4+CD25+ Tregs in the blood of splenectomized rats was significantly increased within 7 days (2.4 ± 0.5%, 4.9 ± 1.3% and 5.3 ± 1.0% for sham, splenectomy and splenectomy + HT, respectively; n = 15/group, sham vs. splenectomy or splenectomy + HT, p splenectomy surgery and gradually decreased to baseline level; 4) Splenectomy increased the rate of lymphocyte apoptosis (day 7: 0.3 ± 0.05%, 3.9 ± 0.9% and 4.1 ± 0.9% for sham, splenectomy and splenectomy + HT, respectively; n = 15/group, sham vs. splenectomy or splenectomy + HT, p Splenectomy inhibits the development of pathology and prolongs the survival time of cardiac allograft. The responsible mechanism is associated with induction of immune

  20. The effect of timing of the first kidney transplantation on survival in children initiating renal replacement therapy

    DEFF Research Database (Denmark)

    Kramer, Anneke; Stel, Vianda S; Geskus, Ronald B

    2012-01-01

    Controversy exists concerning the timing of the first kidney transplantation for children who need to start renal replacement therapy (RRT). Our aim was to estimate the effect of timing of the first transplantation on patient survival in children, for the first time also taking into account...

  1. Survival analysis and prognostic factors of timing of first childbirth among women in Nigeria.

    Science.gov (United States)

    Fagbamigbe, Adeniyi Francis; Idemudia, Erhabor Sunday

    2016-05-13

    First childbirth in a woman's life is one of the most important events in her life. It marks a turnaround when she might have to drop roles of career building and education, for motherhood and parenthood. The timing of the commencement of these roles affects the child bearing behavior of women as they progress in their reproductive ages. Prevalent early first childbirth in Nigeria has been reported as the main cause of high population growth and high  fertility, mortality and morbidity among women, but little has been documented on the progression into first birth as well as factors affecting it in Nigeria. This paper modelled timing of first birth among women in Nigeria and determined socio-demographic and other factors affecting its timing. We hypothesized that background characteristics of a woman will influence her progression into having first birth. We developed and fitted a survival analysis model to understand the timing of first birth among women in Nigeria using a national representative 2013 NDHS data. Women with no children were right censored as of the date of the survey. The Kaplan Meier survival function was used to estimate the probabilities of first birth not occurring until certain ages of women while Cox proportional hazard regression was used to model the timing of first births at 5 % significance level. About 75.7 % of the respondents had given birth in the Northern region of Nigerian compared with 63.8 % in the South. Half (50.1 %) of the first childbirth occurred within the 15-19 years age bracket and 38.1 % within 20-29 years. The overall median survival time to first birth was 20 years (North 19, South 22), 27 years among women with higher education and 18 years for those with no formal education. The adjusted hazard of first birth was higher in the Northern region of Nigeria than in the South (aHR = 1.24, 95 % CI: 1.20-1.27), and higher in rural areas than in urban areas (aHR = 1.15, 95 % CI: 1.12-1.19). Also, hazard of earlier first

  2. Practical considerations when analyzing discrete survival times using the grouped relative risk model.

    Science.gov (United States)

    Altman, Rachel MacKay; Henrey, Andrew

    2017-10-11

    The grouped relative risk model (GRRM) is a popular semi-parametric model for analyzing discrete survival time data. The maximum likelihood estimators (MLEs) of the regression coefficients in this model are often asymptotically efficient relative to those based on a more restrictive, parametric model. However, in settings with a small number of sampling units, the usual properties of the MLEs are not assured. In this paper, we discuss computational issues that can arise when fitting a GRRM to small samples, and describe conditions under which the MLEs can be ill-behaved. We find that, overall, estimators based on a penalized score function behave substantially better than the MLEs in this setting and, in particular, can be far more efficient. We also provide methods of assessing the fit of a GRRM to small samples.

  3. Irradiation shortens the survival time of red cells deficient in glucose-6-phosphate dehydrogenasee

    Energy Technology Data Exchange (ETDEWEB)

    Westerman, M.P. (Rush Medical College, Chicago, IL); Wald, N.; Diloy-Puray, M.

    1980-03-01

    X radiation of glucose-6-phosphate dehydrogenase (G6PD)-deficient red cells causes distinct shortening of their survival time. This is accompanied by significant lowering of reduced glutathione content and is not observed in similarly prepared and treated normal cells. The damage is most likely related to irradiation-induced formation of activated oxygen products and to their subsequent effects on the cells. Neither methemoglobin increases nor Heinz body formation were observed, suggesting that hemolysis occurred prior to these changes. The study provides a model for examining the effects of irradiation and activated oxygen on red cells and suggests that patients with G6PD deficiency who receive irradiation could develop severe hemolysis in certain clinical settings.

  4. Survival analysis using S analysis of time-to-event data

    CERN Document Server

    Tableman, Mara

    2003-01-01

    Survival Analysis Using S: Analysis of Time-to-Event Data is designed as a text for a one-semester or one-quarter course in survival analysis for upper-level or graduate students in statistics, biostatistics, and epidemiology. Prerequisites are a standard pre-calculus first course in probability and statistics, and a course in applied linear regression models. No prior knowledge of S or R is assumed. A wide choice of exercises is included, some intended for more advanced students with a first course in mathematical statistics. The authors emphasize parametric log-linear models, while also detailing nonparametric procedures along with model building and data diagnostics. Medical and public health researchers will find the discussion of cut point analysis with bootstrap validation, competing risks and the cumulative incidence estimator, and the analysis of left-truncated and right-censored data invaluable. The bootstrap procedure checks robustness of cut point analysis and determines cut point(s). In a chapter ...

  5. Time trend analysis of primary tumor resection for stage IV colorectal cancer: less surgery, improved survival.

    Science.gov (United States)

    Hu, Chung-Yuan; Bailey, Christina E; You, Y Nancy; Skibber, John M; Rodriguez-Bigas, Miguel A; Feig, Barry W; Chang, George J

    2015-03-01

    With the advent of effective modern chemotherapeutic and biologic agents, primary tumor resection for patients with stage IV colorectal cancer (CRC) may not be routinely necessary. To evaluate the secular patterns of primary tumor resection use in stage IV CRC in the United States. A retrospective cohort study using data from the National Cancer Institute's Surveillance, Epidemiology, and End Results CRC registry. Demographic and clinical factors were compared for 64,157 patients diagnosed with stage IV colon or rectal cancer from January 1, 1988, through December 31, 2010, who had undergone primary tumor resection and those who had not. Rates of primary tumor resection and median relative survival were calculated for each year. Joinpoint regression analysis was used to determine when a significant change in trend in the primary tumor resection rate had occurred. Logistic regression analysis was used to assess factors associated with primary tumor resection. Difference in primary tumor resection rates over time. Of the 64,157 patients with stage IV CRC, 43,273 (67.4%) had undergone primary tumor resection. The annual rate of primary tumor resection decreased from 74.5% in 1988 to 57.4% in 2010 (Ptrend toward fewer primary tumor resections was seen. Despite the decreasing primary tumor resection rate, patient survival rates improved. However, primary tumor resection may still be overused, and current treatment practices lag behind evidence-based treatment guidelines.

  6. Predicting time to recall in patients conditionally released from a secure forensic hospital: A survival analysis.

    Science.gov (United States)

    Jewell, Amelia; Cocks, Christopher; Cullen, Alexis E; Fahy, Tom; Dean, Kimberlie

    2018-01-17

    The recall of conditionally discharged forensic patients in England is a formal order from the Ministry of Justice under the Mental Health Act (1983) which has the power to revoke conditional release and direct readmission to hospital. Recall has significant implications for the individual and for hospital services, but despite this, little is known about predictors of recall for forensic patients. We examined the rate of recall for 101 patients conditionally discharged from medium secure forensic inpatient services between 2007 and 2013. Demographic, clinical, and forensic factors were examined as possible predictors of time to recall using Cox regression survival techniques. Conditionally discharged patients were followed for an average of 811 days, during which 45 (44.5%) were recalled to hospital. Younger age (HR 1.89; 95% CI 1.02-3.49; p = 0.04), non-white ethnicity (HR 3.44; 95% CI 1.45-8.13), substance abuse history (HR 2.52; 95% CI 1.17-5.43), early violence (HR 1.90; 95% CI 1.03-3.50), early childhood maladjustment (HR 1.92; 95% CI 1.01-3.68), treatment with a depot medication (HR 2.17; 95% CI 1.14-4.11), being known to mental health services (HR 3.44; 95% CI 1.06-11.16), and a psychiatric admission prior to the index admission (HR 2.44; 95% CI 1.08-5.52) were significantly associated with a shorter time to recall. Treatment with clozapine reduced the risk of recall to hospital (HR 0.40; 95% CI 0.20-0.79). Time to recall can be predicted by a range of factors that are readily available to clinical teams. Further research is required to determine if targeted interventions can modify the likelihood or time to recall for conditionally released forensic patients. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  7. Restricted mean survival time over 15 years for patients starting renal replacement therapy.

    Science.gov (United States)

    Couchoud, Cécile; Dantony, Emmanuelle; Elsensohn, Mad-Hélénie; Villar, Emmanuel; Vigneau, Cécile; Moranne, Olivier; Rabilloud, Muriel; Ecochard, René

    2017-04-01

    The restricted mean survival time (RMST) estimates life expectancy up to a given time horizon and can thus express the impact of a disease. The aim of this study was to estimate the 15-year RMST of a hypothetical cohort of incident patients starting renal replacement therapy (RRT), according to their age, gender and diabetes status, and to compare it with the expected RMST of the general population. Using data from 67 258 adult patients in the French Renal Epidemiology and Information Network (REIN) registry, we estimated the RMST of a hypothetical patient cohort (and its subgroups) for the first 15 years after starting RRT (cRMST) and used the general population mortality tables to estimate the expected RMST (pRMST). Results were expressed in three different ways: the cRMST, which calculates the years of life gained under the hypothesis of 100% death without RRT treatment, the difference between the pRMST and the cRMST (the years lost), and a ratio expressing the percentage reduction of the expected RMST: (pRMST - cRMST)/pRMST. Over their first 15 years of RRT, the RMST of end-stage renal disease (ESRD) patients decreased with age, ranging from 14.3 years in patients without diabetes aged 18 years at ESRD to 1.8 years for those aged 90 years, and from 12.7 to 1.6 years, respectively, for those with diabetes; expected RMST varied from 15.0 to 4.1 years between 18 and 90 years. The number of years lost in all subgroups followed a bell curve that was highest for patients aged 70 years. After the age of 55 years in patients with and 70 years in patients without diabetes, the reduction of the expected RMST was >50%. While neither a clinician nor a survival curve can predict with absolute certainty how long a patient will live, providing estimates on years gained or lost, or percentage reduction of expected RMST, may improve the accuracy of the prognostic estimates that influence clinical decisions and information given to patients.

  8. Association of serum lipid levels over time with survival in incident peritoneal dialysis patients.

    Science.gov (United States)

    Park, Cheol Ho; Kang, Ea Wha; Park, Jung Tak; Han, Seung Hyeok; Yoo, Tae-Hyun; Kang, Shin-Wook; Chang, Tae Ik

    The association of dyslipidemia with mortality has not been fully evaluated in patients on peritoneal dialysis (PD). Moreover, changes in lipids levels over time and associated death risk have not yet been studied in this population. We studied the association of time-updated serum lipid concentrations with all-cause and cardiovascular (CV) mortalities in a 10-year cohort of 749 incident PD patients. Association was assessed using time-varying Cox proportional hazard regression models with adjustment for multiple variables including statin therapy. During a median follow-up of 36 (interquartile range, 21-61) months, 273 all-cause and 107 CV deaths occurred. Compared with those with total cholesterol (TC) of 180 to <210 or low-density lipoprotein cholesterol (LDL-C) of 100 to <130 mg/dL, hazard ratios (95% confidence interval) of the lowest TC (<150 mg/dL) and LDL-C (<70 mg/dL) were 2.32 (1.61-3.35) and 2.02 (1.45-2.83) for all-cause mortality and 1.87 (1.04-3.37) and 1.92 (1.13-3.26) for CV mortality, respectively. Lower triglyceride (<100 mg/dL) and high-density lipoprotein cholesterol (<30 mg/dL) levels were associated with higher all-cause mortality (1.66 [1.11-2.47] and 1.57 [1.08-2.29]) but not with CV mortality. Contrary to the general population, lower TC and LDL-C levels over time were significantly associated with both worse survival and increased CV mortality in incident PD patients. Although lower triglyceride and high-density lipoprotein cholesterol concentrations were associated with significantly higher all-cause mortality, they failed to show any clear association with CV mortality. The underlying mechanisms responsible for this apparent paradox await further investigations. Copyright © 2017 National Lipid Association. Published by Elsevier Inc. All rights reserved.

  9. Surviving blind decomposition: A distributional analysis of the time-course of complex word recognition.

    Science.gov (United States)

    Schmidtke, Daniel; Matsuki, Kazunaga; Kuperman, Victor

    2017-11-01

    The current study addresses a discrepancy in the psycholinguistic literature about the chronology of information processing during the visual recognition of morphologically complex words. Form-then-meaning accounts of complex word recognition claim that morphemes are processed as units of form prior to any influence of their meanings, whereas form-and-meaning models posit that recognition of complex word forms involves the simultaneous access of morphological and semantic information. The study reported here addresses this theoretical discrepancy by applying a nonparametric distributional technique of survival analysis (Reingold & Sheridan, 2014) to 2 behavioral measures of complex word processing. Across 7 experiments reported here, this technique is employed to estimate the point in time at which orthographic, morphological, and semantic variables exert their earliest discernible influence on lexical decision RTs and eye movement fixation durations. Contrary to form-then-meaning predictions, Experiments 1-4 reveal that surface frequency is the earliest lexical variable to exert a demonstrable influence on lexical decision RTs for English and Dutch derived words (e.g., badness; bad + ness), English pseudoderived words (e.g., wander; wand + er) and morphologically simple control words (e.g., ballad; ball + ad). Furthermore, for derived word processing across lexical decision and eye-tracking paradigms (Experiments 1-2; 5-7), semantic effects emerge early in the time-course of word recognition, and their effects either precede or emerge simultaneously with morphological effects. These results are not consistent with the premises of the form-then-meaning view of complex word recognition, but are convergent with a form-and-meaning account of complex word recognition. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  10. Dietary magnesium and copper affect survival time and neuroinflammation in chronic wasting disease.

    Science.gov (United States)

    Nichols, Tracy A; Spraker, Terry R; Gidlewski, Thomas; Cummings, Bruce; Hill, Dana; Kong, Qingzhong; Balachandran, Aru; VerCauteren, Kurt C; Zabel, Mark D

    2016-05-03

    Chronic wasting disease (CWD), the only known wildlife prion disease, affects deer, elk and moose. The disease is an ongoing and expanding problem in both wild and captive North American cervid populations and is difficult to control in part due to the extreme environmental persistence of prions, which can transmit disease years after initial contamination. The role of exogenous factors in CWD transmission and progression is largely unexplored. In an effort to understand the influence of environmental and dietary constituents on CWD, we collected and analyzed water and soil samples from CWD-negative and positive captive cervid facilities, as well as from wild CWD-endozootic areas. Our analysis revealed that, when compared with CWD-positive sites, CWD-negative sites had a significantly higher concentration of magnesium, and a higher magnesium/copper (Mg/Cu) ratio in the water than that from CWD-positive sites. When cevidized transgenic mice were fed a custom diet devoid of Mg and Cu and drinking water with varied Mg/Cu ratios, we found that higher Mg/Cu ratio resulted in significantly longer survival times after intracerebral CWD inoculation. We also detected reduced levels of inflammatory cytokine gene expression in mice fed a modified diet with a higher Mg/Cu ratio compared to those on a standard rodent diet. These findings indicate a role for dietary Mg and Cu in CWD pathogenesis through modulating inflammation in the brain.

  11. Long-Time Survival of a Patient with Metastatic Pancreatic Cancer: A Case Report

    Directory of Open Access Journals (Sweden)

    Željko Soldić

    2011-08-01

    Full Text Available Pancreatic cancer is a malignant neoplasm of the pancreas. It does not cause any symptoms in the early stage, and later symptoms are nonspecific, thus the disease is usually diagnosed when already advanced. In 2008, pancreatic cancer ranked eighth on the list of the 10 most common cancers among men in Croatia and tenth on the list of the most common cancers among Croatian women. Pancreatic cancer has a poor prognosis, with a survival time of only 6–8 months for metastatic disease. Gemcitabine is the standard chemotherapeutic option. Other chemotherapeutic agents include5-fluorouracil and leucovorin. In this paper, we present a case of a patient diagnosed with locally advanced and metastatic pancreatic cancer, who is still alive and currently receives his fourth line of chemotherapy 5 years after the diagnosis. Following disease progression on gemcitabine chemotherapy, he was treated with chemoradiotherapy which, however, had no effect. We then applied cisplatin monochemotherapy which offered excellent disease control, was well tolerated by the patient and, although somewhat obsolete in this form, showed to be a valuable chemotherapeutic option.

  12. Impact of collaborative care on survival time for dogs with congestive heart failure and revenue for attending primary care veterinarians.

    Science.gov (United States)

    Lefbom, Bonnie K; Peckens, Neal K

    2016-07-01

    OBJECTIVE To assess the effects of in-person collaborative care by primary care veterinarians (pcDVMs) and board-certified veterinary cardiologists (BCVCs) on survival time of dogs after onset of congestive heart failure (CHF) and on associated revenue for the attending pcDVMs. DESIGN Retrospective cohort study. ANIMALS 26 small-breed dogs treated for naturally occurring CHF secondary to myxomatous mitral valve disease at a multilocation primary care veterinary hospital between 2008 and 2013. PROCEDURES Electronic medical records were reviewed to identify dogs with confirmed CHF secondary to myxomatous mitral valve disease and collect information on patient care, survival time, and pcDVM revenue. Data were compared between dogs that received collaborative care from the pcDVM and a BCVC and dogs that received care from the pcDVM alone. RESULTS Dogs that received collaborative care had a longer median survival time (254 days) than did dogs that received care from the pcDVM alone (146 days). A significant positive correlation was identified between pcDVM revenue and survival time for dogs that received collaborative care (ie, the longer the dog survived, the greater the pcDVM revenue generated from caring for that patient). CONCLUSIONS AND CLINICAL RELEVANCE Findings suggested that collaborative care provided to small-breed dogs with CHF by a BCVC and pcDVM could result in survival benefits for affected dogs and increased revenue for pcDVMs, compared with care provided by a pcDVM alone.

  13. Entrainment and Survival Time of the Llsvps: Effects of Flow in the Thermochemical Pile Interior

    Science.gov (United States)

    Mulyukova, E.; Steinberger, B. M.; Dabrowski, M.; Sobolev, S. V.

    2013-12-01

    One of the most robust results from tomographic studies is the existence of two antipodally located Large Low Shear Velocity Provinces (LLSVPs) at the base of the mantle, which appear to be chemically denser than the ambient mantle. Results from reconstruction studies (Torsvik et al., 2006) infer that the LLSVPs are stable, long-lived, and are sampled by deep mantle plumes that rise predominantly from their margins. The amount of the anomalous LLSVP-material that gets entrained into the rising plumes poses a constraint on the survival time of the LLSVPs, as well as on the plume buoyancy, on the lithospheric uplift associated with plume interaction and geochemical signature of the erupted lavas observed at the Earth's surface. Recent estimates for the plume responsible for the formation of the Siberian Flood Basalts give about 15% of entrained dense recycled oceanic crust, which made the hot mantle plume almost neutrally buoyant (Sobolev et al., 2011). If it wasn't for the destabilizing flow, or entrainment, by the hot rising plumes, the anomalously dense material in the Earth's deep mantle may have never made its way to the surface. In order for the entrainment to take place, the destabilizing viscous stresses acting on a volume of anomalously dense material must exceed the gravitationally stabilizing stresses associated with buoyancy. At what conditions are these criteria met in a dynamically active deep mantle? To investigate this question, we perform numerical simulations of thermal convection with presence of a chemically dense basal layer in a 2D Cartesian box. In agreement with other studies, we find that the governing parameters are the buoyancy ratio between the thermal and the chemical density anomalies, as well as the viscosity variations. We observe that for a range of these parameters, an internal convective flow in the interior of the dense layer can develop. This internal flow has an important effect on the evolution of the entire system. First of all

  14. Sex-related time-dependent variations in post-stroke survival-evidence of a female stroke survival advantage

    DEFF Research Database (Denmark)

    Olsen, Tom Skyhøj; Dehlendorff, Christian; Andersen, Klaus Kaae

    2007-01-01

    of stroke and remained so during the first month suggesting a female survival advantage. Throughout the second month the rate reversed in favour of men suggesting that women in that period are paying a 'toll' for their initial survival advantage. Hereafter, the rate steadily decreased, and after 4 months...

  15. Time of Time

    Science.gov (United States)

    Allen Emerson, E.

    In his landmark 1977 paper "The Temporal Logic of Programs", Amir Pnueli gave a fundamental recognition that the ideally nonterminating behavior of ongoing concurrent programs, such as operating systems and protocols, was a vital aspect of program reasoning. As classical approaches to program correctness were based on initial-state/final-state semantics for terminating programs, these approaches were inapplicable to programs where infinite behavior was the norm. To address this shortcoming, Pnueli suggested the use of temporal logic, a formalism for reasoning about change over time originally studied by philosophers, to meaningfully describe and reason about the infinite behavior of programs. This suggestion turned out to be remarkably fruitful. It struck a resonant chord within the formal verification community, and it has had an enormous impact on the development of the area. It matured into an extremely effective mathematical tool for specifying and verifying a vast class of synchronization and coordination problems common in concurrency. Pnueli thus caused a sea-change in the field of program verification, founding the time of reasoning about time, which has been the most successful period in formal methods yet.

  16. Breast cancer and leptomeningeal disease (LMD): hormone receptor status influences time to development of LMD and survival from LMD diagnosis.

    Science.gov (United States)

    Yust-Katz, S; Garciarena, P; Liu, D; Yuan, Y; Ibrahim, N; Yerushalmi, R; Penas-Prado, M; Groves, M D

    2013-09-01

    Leptomeningeal disease (LMD) occurs in 5 % of breast cancer patients. The aim of this study was to identify risk factors related to survival and time to development of LMD in breast cancer patients. A retrospective analysis of breast cancer patients with LMD, evaluated in MDACC between 1995 and 2011. 103 patients with diagnosis of breast cancer and LMD were identified (one male). The median age at LMD diagnosis was 49.2 years. 78.2 % had invasive ductal carcinoma. Hormone receptors (HRs) were positive in 55.3 % of patients, 47.4 % were human epidermal growth factor receptor 2-positive and 22.8 % were triple negative. 52 % of the patients were treated with WBRT, 19 % with spinal radiation, 36 % with systemic chemotherapy and 55 % with intrathecal chemotherapy. Estimated median overall survival from time of breast cancer diagnosis was 3.66 years. Median survival from time of LMD diagnosis was 4.2 months. Time from breast cancer diagnosis to LMD was 2.48 years. In multivariate analysis, HR status and stage at diagnosis were significantly associated with time to LMD diagnosis (p < 0.05). In triple negative patients, time to LMD was shorter. In patients who were HR positive, time to LMD was longer. Survival from LMD diagnosis was significantly associated with both treatment, as well as positive HR status (multivariate analysis p < 0.05). In conclusion LMD has dismal prognosis in breast cancer patients. HR status contributes to time to LMD diagnosis and survival from LMD diagnosis. The impact of treatment aimed at LMD cannot be ascertained in our retrospective study due to the inherent bias associated with the decision to treat.

  17. The accuracy of survival time prediction for patients with glioma is improved by measuring mitotic spindle checkpoint gene expression.

    Directory of Open Access Journals (Sweden)

    Li Bie

    Full Text Available Identification of gene expression changes that improve prediction of survival time across all glioma grades would be clinically useful. Four Affymetrix GeneChip datasets from the literature, containing data from 771 glioma samples representing all WHO grades and eight normal brain samples, were used in an ANOVA model to screen for transcript changes that correlated with grade. Observations were confirmed and extended using qPCR assays on RNA derived from 38 additional glioma samples and eight normal samples for which survival data were available. RNA levels of eight major mitotic spindle assembly checkpoint (SAC genes (BUB1, BUB1B, BUB3, CENPE, MAD1L1, MAD2L1, CDC20, TTK significantly correlated with glioma grade and six also significantly correlated with survival time. In particular, the level of BUB1B expression was highly correlated with survival time (p<0.0001, and significantly outperformed all other measured parameters, including two standards; WHO grade and MIB-1 (Ki-67 labeling index. Measurement of the expression levels of a small set of SAC genes may complement histological grade and other clinical parameters for predicting survival time.

  18. Patients with type 2 diabetes benefit from primary care-based disease management: a propensity score matched survival time analysis.

    Science.gov (United States)

    Drabik, Anna; Büscher, Guido; Thomas, Karsten; Graf, Christian; Müller, Dirk; Stock, Stephanie

    2012-08-01

    This study aimed to assess the impact of a nationwide German diabetes mellitus disease management program (DMP) on survival time and costs in comparison to routine care. The authors conducted a retrospective observational cohort study using routine administration data from Germany's largest sickness fund to identify insured suffering from diabetes in 2002. A total of 95,443 insured with type 2 diabetes mellitus who were born before January 1, 1962 met the defined inclusion criteria, resulting in 19,888 pairs of DMP participants and nonparticipants matched for socioeconomic and health status using propensity score matching methods. This is the first time propensity score matching has been used to evaluate a survival benefit of DMPs. In the time frame analyzed (3 years), mean survival time for the DMP group was 1045 days vs. 985 days for the routine care group (Pdiabetes mellitus in the German Statutory Health Insurance showed a significant benefit in survival time. They also incurred lower costs compared to propensity score matched insured in routine care.

  19. A mixed linear model controlling for case underascertainment across multiple cancer registries estimated time trends in survival.

    Science.gov (United States)

    Dahm, Stefan; Bertz, Joachim; Barnes, Benjamin; Kraywinkel, Klaus

    2018-01-10

    Large temporal and geographical variation in survival rates estimated from epidemiological cancer registries coupled with heterogeneity in death certificate only (DCO) notifications makes it difficult to interpret trends in survival. The aim of our study is to introduce a method for estimating such trends while accounting for heterogeneity in DCO notifications in a cancer site-specific manner. We used the data of 4.0 million cancer cases notified in 14 German epidemiological cancer registries. Annual 5-year relative survival rates from 2002 through 2013 were estimated, and proportions of DCO notifications were recorded. "DCO-excluded" survival rates were regressed on DCO proportions and calendar years using a mixed linear model with cancer registry as a random effect. Based on this model, trends in survival rates were estimated for Germany at 0% DCO. For most cancer sites and age groups, we estimated significant positive trends in survival. Age-standardized survival for all cancers combined increased by 7.1% units for women and 10.8% units for men. The described method could be used to estimate trends in cancer survival based on the data from epidemiological cancer registries with differing DCO proportions and with changing DCO proportions over time. Copyright © 2018 Elsevier Inc. All rights reserved.

  20. Neurogenesis and the Spacing Effect: Learning over Time Enhances Memory and the Survival of New Neurons

    Science.gov (United States)

    Sisti, Helene M.; Glass, Arnold L.; Shors, Tracey J.

    2007-01-01

    Information that is spaced over time is better remembered than the same amount of information massed together. This phenomenon, known as the spacing effect, was explored with respect to its effect on learning and neurogenesis in the adult dentate gyrus of the hippocampal formation. Because the cells are generated over time and because learning…

  1. The effect of time of planting at stake on cocoa seedling survival ...

    African Journals Online (AJOL)

    Studies were conducted at the Cocoa Research Institute of Ghana, Tafo and its sub-station at Bunso, from 1994 to 1997 to re-appraise the success of cocoa etablishment from seeds sown at stake at specified times of the year before the onset of the dry season. The treatments consisted of four times within the year when ...

  2. Does the benefit on survival from leisure time physical activity depend on physical activity at work?

    DEFF Research Database (Denmark)

    Holtermann, Andreas; Marott, Jacob Louis; Gyntelberg, Finn

    2013-01-01

    To investigate if persons with high physical activity at work have the same benefits from leisure time physical activity as persons with sedentary work.......To investigate if persons with high physical activity at work have the same benefits from leisure time physical activity as persons with sedentary work....

  3. The effect of time to defibrillation and targeted temperature management on functional survival after out-of-hospital cardiac arrest.

    Science.gov (United States)

    Drennan, Ian R; Lin, Steve; Thorpe, Kevin E; Morrison, Laurie J

    2014-11-01

    Cardiac arrest physiology has been proposed to occur in three distinct phases: electrical, circulatory and metabolic. There is limited research evaluating the relationship of the 3-phase model of cardiac arrest to functional survival at hospital discharge. Furthermore, the effect of post-cardiac arrest targeted temperature management (TTM) on functional survival during each phase is unknown. To determine the effect of TTM on the relationship between the time of initial defibrillation during each phase of cardiac arrest and functional survival at hospital discharge. This was a retrospective observational study of consecutive adult (≥18 years) out-of-hospital cardiac arrest (OHCA) patients with initial shockable rhythms. Included patients obtained a return of spontaneous circulation (ROSC) and were eligible for TTM. Multivariable logistic regression was used to determine predictors of functional survival at hospital discharge. There were 20,165 OHCA treated by EMS and 871 patients were eligible for TTM. Of these patients, 622 (71.4%) survived to hospital discharge and 487 (55.9%) had good functional survival. Good functional survival was associated with younger age (OR 0.94; 95% CI 0.93-0.95), shorter times from collapse to initial defibrillation (OR 0.73; 95% CI 0.65-0.82), and use of post-cardiac arrest TTM (OR 1.49; 95% CI 1.07-2.30). Functional survival decreased during each phase of the model (65.3% vs. 61.7% vs. 50.2%, Pdefibrillation and was decreased during each successive phase of the 3-phase model. Post-cardiac arrest TTM was associated with improved functional survival. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  4. The Impact of Radiation Treatment Time on Survival in Patients With Head and Neck Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Shaikh, Talha [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Handorf, Elizabeth A. [Department of Biostatistics, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Murphy, Colin T. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Mehra, Ranee [Department of Medical Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Ridge, John A. [Department of Surgical Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Galloway, Thomas J., E-mail: Thomas.Galloway@fccc.edu [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States)

    2016-12-01

    Purpose: To assess the impact of radiation treatment time (RTT) in head and neck cancers on overall survival (OS) in the era of chemoradiation. Methods and Materials: Patients with diagnoses of tongue, hypopharynx, larynx, oropharynx, or tonsil cancer were identified by use of the National Cancer Database. RTT was defined as date of first radiation treatment to date of last radiation treatment. In the definitive setting, prolonged RTT was defined as >56 days, accelerated RTT was defined as <47 days, and standard RTT was defined as 47 to 56 days. In the postoperative setting, prolonged RTT was defined as >49 days, accelerated RTT was defined as <40 days, and standard RTT was defined as 40 to 49 days. We used χ{sup 2} tests to identify predictors of RTT. The Kaplan-Meier method was used to compare OS among groups. Cox proportional hazards model was used for OS analysis in patients with known comorbidity status. Results: 19,531 patients were included; 12,987 (67%) had a standard RTT, 4,369 (34%) had an accelerated RTT, and 2,165 (11%) had a prolonged RTT. On multivariable analysis, accelerated RTT (hazard ratio [HR] 0.84; 95% confidence interval [CI] 0.73-0.97) was associated with an improved OS, and prolonged RTT (HR 1.25; 95% CI 1.14-1.37) was associated with a worse OS relative to standard RTT. When the 9,200 (47%) patients receiving definitive concurrent chemoradiation were examined, prolonged RTT (HR 1.29; 95% CI 1.11-1.50) was associated with a worse OS relative to standard RTT, whereas there was no significant association between accelerated RTT and OS (HR 0.76; 95% CI 0.57-1.01). Conclusion: Prolonged RTT is associated with worse OS in patients receiving radiation therapy for head and neck cancer, even in the setting of chemoradiation. Expeditious completion of radiation should continue to be a quality metric for the management of head and neck malignancies.

  5. Determinants of treatment waiting times for head and neck cancer in the Netherlands and their relation to survival.

    Science.gov (United States)

    van Harten, Michel C; Hoebers, Frank J P; Kross, Kenneth W; van Werkhoven, Erik D; van den Brekel, Michiel W M; van Dijk, Boukje A C

    2015-03-01

    Waiting to start treatment has been shown to be associated with tumor progression and upstaging in head and neck squamous cell carcinomas (HNSCCs). This diminishes the chance of cure and might lead to unnecessary mortality. We investigated the association between waiting times and survival in the Netherlands and assessed which factors were associated to longer waiting times. Patient (age, sex, socioeconomic status (SES), tumor (site, stage) and treatment (type, of institute of diagnosis/treatment) characteristics for patients with HNSCC who underwent treatment were extracted from the Netherlands Cancer Registry (NCR) for 2005-2011. Waiting time was defined as the number of days between histopathological diagnosis and start of treatment. Univariable and multivariable Cox regression was used to evaluate survival. In total, 13,140 patients were included, who had a median waiting time of 37days. Patients who were more likely to wait longer were men, patients with a low SES, oropharynx tumors, stage IV tumors, patients to be treated with radiotherapy or chemoradiation, and patients referred for treatment to a Head and Neck Oncology Center (HNOC) from another hospital. The 5-year overall survival was 58% for all patients. Our multivariable Cox regression model showed that longer waiting time, was significantly related to a higher hazard of dying (p<0.0001). This is the first large population-based study showing that longer waiting time for surgery, radiotherapy or chemoradiation is a significant negative prognostic factor for HNSCC patients. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Differences in the timing of cardio-respiratory development determine whether marine gastropod embryos survive or die in hypoxia.

    Science.gov (United States)

    Rudin-Bitterli, Tabitha S; Spicer, John I; Rundle, Simon D

    2016-04-01

    Physiological plasticity of early developmental stages is a key way by which organisms can survive and adapt to environmental change. We investigated developmental plasticity of aspects of the cardio-respiratory physiology of encapsulated embryos of a marine gastropod, Littorina obtusata, surviving exposure to moderate hypoxia (PO2 =8 kPa) and compared the development of these survivors with that of individuals that died before hatching. Individuals surviving hypoxia exhibited a slower rate of development and altered ontogeny of cardio-respiratory structure and function compared with normoxic controls (PO2 >20 kPa). The onset and development of the larval and adult hearts were delayed in chronological time in hypoxia, but both organs appeared earlier in developmental time and cardiac activity rates were greater. The velum, a transient, 'larval' organ thought to play a role in gas exchange, was larger in hypoxia but developed more slowly (in chronological time), and velar cilia-driven, rotational activity was lower. Despite these effects of hypoxia, 38% of individuals survived to hatching. Compared with those embryos that died during development, these surviving embryos had advanced expression of adult structures, i.e. a significantly earlier occurrence and greater activity of their adult heart and larger shells. In contrast, embryos that died retained larval cardio-respiratory features (the velum and larval heart) for longer in chronological time. Surviving embryos came from eggs with significantly higher albumen provisioning than those that died, suggesting an energetic component for advanced development of adult traits. © 2016. Published by The Company of Biologists Ltd.

  7. Determine the Influence of Time Held in “Knockdown” Anesthesia on Survival and Stress of Surgically Implanted Juvenile Salmonids

    Energy Technology Data Exchange (ETDEWEB)

    Woodley, Christa M.; Wagner, Katie A.; Knox, Kasey M.

    2012-01-31

    The Juvenile Salmon Acoustic Telemetry System (JSATS) was developed for the U.S. Army Corp of Engineers Portland District (USACE) to address questions related to survival and performance measures of juvenile salmonids as they pass through the Federal Columbia River Power System (FCRPS). Researchers using JSATS acoustic transmitters (ATs) were tasked with standardizing the surgical implantation procedure to ensure that the stressors of handling and surgery on salmonids were consistent and less likely to cause effects of tagging in survival studies. Researchers questioned whether the exposure time in 'knockdown' anesthesia (or induction) to prepare fish for surgery could influence the survival of study fish (CBSPSC 2011). Currently, fish are held in knockdown anesthesia after they reach Stage 4 anesthesia until the completion of the surgical implantation of a transmitter, varies from 5 to 15 minutes for studies conducted in the Columbia Basin. The Columbia Basin Surgical Protocol Steering Committee (CBSPSC ) expressed concern that its currently recommended 10-minute maximum time limit during which fish are held in anesthetic - tricaine methanesulfonate (MS-222, 80 mg L-1 water) - could increase behavioral and physiological costs, and/or decrease survival of outmigrating juvenile salmonids. In addition, the variability in the time fish are held at Stage 4 could affect the data intended for direct comparison of fish within or among survival studies. Under the current recommended protocol, if fish exceed the 10-minute time limit, they are to be released without surgical implantation, thereby increasing the number of fish handled and endangered species 'take' at the bypass systems for FCRPS survival studies.

  8. Effect of length biased sampling of unobserved sojourn times on the survival distribution when disease is screen detected.

    Science.gov (United States)

    Kafadar, Karen; Prorok, Philip C

    2009-07-20

    Data can arise as a length-biased sample rather than as a random sample; e.g. a sample of patients in hospitals or of network cable lines (experimental units with longer stays or longer lines have greater likelihoods of being sampled). The distribution arising from a single length-biased sampling (LBS) time has been derived (e.g. (The Statistical Analysis of Discrete Time Events. Oxford Press: London, 1972)) and applies when the observed outcome relates to the random variable subjected to LBS. Zelen (Breast Cancer: Trends in Research and Treatment. Raven Press: New York, 1976; 287-301) noted that cases of disease detected from a screening program likewise form a length-biased sample among all cases, since longer sojourn times afford greater likelihoods of being screen detected. In contrast to the samples on hospital stays and cable lines, however, the length-biased sojourns (preclinical durations) cannot be observed, although their subsequent clinical durations (survival times) are. This article quantifies the effect of LBS of the sojourn times (or pre-clinical durations) on the distribution of the observed clinical durations when cases undergo periodic screening for the early detection of disease. We show that, when preclinical and clinical durations are positively correlated, the mean, median, and quartiles of the distribution of the clinical duration from screen-detected cases can be substantially inflated-even in the absence of any benefit on survival from the screening procedure. Screening studies that report mean survival time need to take account of the fact that, even in the absence of any real benefit, the mean survival among cases in the screen-detected group will be longer than that among interval cases or among cases that arise in the control arm, above and beyond lead time bias, simply by virtue of the LBS phenomenon

  9. Impact of Sodium Chloride and Heat on Survival Time of Linguatula Serrata Nymphs in vitro: An Experimental Study

    Directory of Open Access Journals (Sweden)

    B. Hajimohammadi

    2012-07-01

    Full Text Available Introduction: Linguatula serrata is a zoonotic parasite, belonging to the class Pentastomida. The major aim of this study was to evaluate the impact of sodium chloride (NaCl and heat on survival time of Linguatula serrata nymphs. Materials & Methods: Thirty nymphs (10 in triplicate were separately transferred to plastic tubes, containing different concentrations of NaCl solution (2%, 5% and 10%. Meanwhile, 30 nymphs in tubes containing Phosphate Buffer Saline (PBS were separately treated by +50°C, +60°C and +72°C. As control group, thirty nymphs were stored in PBS at +4°C. The effects of different conditions on survival time of the nymphs were evaluated by observing their motility in different periods of time. Results: The survival time of the nymphs stored in 10% NaCl solution was too short and all of them were dead after 3 hours. But the other ones maintained in 2% NaCl solution were significantly more resistant (p<0.05 and were survived for 2 days. All the nymphs pertaining to each +60°C and +72°C treatments were found dead after first 5-minute storage interval; the nymphs stored at +50°C died totally after 20 minutes. The nymphs maintained in PBS at +4°C (control group showed the longest survival time (p<0.05; all of them were alive until day 4 and the last ones died on day 34. Conclusion: It is concluded that salting and heating have significant parasiticidal effects on L. serrata nymphs and could be used as disinfecting methods in processing of meat products especially liver. However, refrigeration at +4°C increases the resistance of the nymphs in meat products and therefore might endanger the food safety.

  10. Survival times of patients with a first hip fracture with and without subsequent major long-bone fractures.

    Science.gov (United States)

    Angthong, Chayanin; Angthong, Wirana; Harnroongroj, Thos; Naito, Masatoshi; Harnroongroj, Thossart

    2013-01-01

    Survival rates are poorer after a second hip fracture than after a first hip fracture. Previous survival studies have included in-hospital mortality. Excluding in-hospital deaths from the analysis allows survival times to be evaluated in community-based patients. There is still a lack of data regarding the effects of subsequent fractures on survival times after hospital discharge following an initial hip fracture. This study compared the survival times of community-dwelling patients with hip fracture who had or did not have a subsequent major long-bone fracture. Hazard ratios and risk factors for subsequent fractures and mortality rates with and without subsequent fractures were calculated. Of 844 patients with hip fracture from 2000 through 2008, 71 had a subsequent major long-bone fracture and 773 did not. Patients who died of other causes, such as perioperative complications, during hospitalization were excluded. Such exclusion allowed us to determine the effect of subsequent fracture on the survival of community-dwelling individuals after hospital discharge or after the time of the fracture if they did not need hospitalization. Demographic data, causes of death, and mortality rates were recorded. Differences in mortality rates between the patient groups and hazard ratios were calculated. Mortality rates during the first year and from 1 to 5 years after the most recent fracture were 5.6% and 1.4%, respectively, in patients with subsequent fractures, and 4.7% and 1.4%, respectively, in patients without subsequent fractures. These rates did not differ significantly between the groups. Cox regression analysis and calculation of hazard ratios did not show significant differences between patients with subsequent fractures and those without. On univariate and multivariate analyses, age fracture. This study found that survival times did not differ significantly between patients with and without subsequent major long-bone fractures after hip fracture. Therefore, all

  11. Relationship between Plasma Fibroblast Growth Factor-23 Concentration and Survival Time in Cats with Chronic Kidney Disease.

    Science.gov (United States)

    Geddes, R F; Elliott, J; Syme, H M

    2015-01-01

    Fibroblast growth factor-23 (FGF-23) and parathyroid hormone (PTH) are commonly increased in cats with azotemic chronic kidney disease (CKD). Both are predictors of survival time in human patients, but these relationships have not previously been examined in the cat. To investigate the relationship between plasma FGF-23 and PTH concentrations at diagnosis of CKD in cats with survival time and with disease progression over 12 months. 214 azotemic, client-owned cats (≥9 years). Retrospective study: Biochemical and urinary variables at diagnosis of azotemic CKD, including plasma FGF-23 and PTH concentrations were assessed as predictors of survival time (all-cause mortality) using Cox regression, and as predictors of CKD progression over 12 months using logistic regression. In the final multivariable Cox regression model, survival was negatively associated with plasma creatinine (P = .002) and FGF-23 concentrations (P = .014), urine protein-to-creatinine ratio (P cats with CKD, independent of other factors including plasma creatinine and phosphate concentrations. Further work is required to assess if FGF-23 contributes directly to CKD progression, but regardless these findings may make FGF-23 a useful biomarker for predicting poorer outcomes in cats with CKD. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  12. Analysis of individual- and time-specific covariate effects on survival of Serinus serinus in north-eastern Spain

    Science.gov (United States)

    Conroy, M.J.; Senar, J.C.; Domenech, J.

    2002-01-01

    We developed models for the analysis of recapture data for 2678 serins (Serinus serinus) ringed in north-eastern Spain since 1985. We investigated several time- and individual-specific factors as potential predictors of overall mortality and dispersal patterns, and of gender and age differences in these patterns. Time-specific covariates included minimum daily temperature, days below freezing, and abundance of a strong competitor, siskins (Carduelis spinus) during winter, and maximum temperature and rainfall during summer. Individual covariates included body mass (i.e. body condition), and wing length (i.e. flying ability), and interactions between body mass and environmental factors. We found little support of a predictive relationship between environmental factors and survival, but good evidence of relationships between body mass and survival, especially for juveniles. Juvenile survival appears to vary in a curvilinear manner with increasing mass, suggesting that there may exist an optimal mass beyond which increases are detrimental. The mass-survival relationship does seem to be influenced by at least one environmental factor, namely the abundance of wintering siskins. When siskins are abundant, increases in body mass appear to relate strongly to increasing survival. When siskin numbers are average or low the relationship is largely reversed, suggesting that the presence of strong competition mitigates the otherwise largely negative aspects of greater body mass. Wing length in juveniles also appears to be related positively to survival, perhaps largely due to the influence of a few unusually large juveniles with adult-like survival. Further work is needed to test these relationships, ideally under experimentation.

  13. The dwell time and survival rates of PICC placement after balloon angioplasty in patient with unexpected central venous obstruction.

    Science.gov (United States)

    Kim, Ki Hyun; Park, Sang Woo; Chang, Il Soo; Yim, Younghee

    2016-09-21

    To evaluate the dwell time and actual survival rates of peripherally inserted central catheter (PICC) placements after balloon angioplasty in patients with unexpected central venous obstructions. Data were obtained on all PICC insertions performed in a tertiary care hospital from August 2008 to December 2013. Thirty-five PICCs attempted after balloon angioplasty in 25 patients (15 male and 10 female patients; mean age, 63 years). Fisher's exact test was used to test for differences in reasons for catheter removal between the groups of patients with stenosis or obstructions. Survival curves for PICC dwell time of all patients, stenosis group, and obstruction group were generated separately using Kaplan-Meier survival analysis and compared with log-rank tests. There were a total 21 obstructions and 14 stenoses. The overall technical success rate of PICC placement after balloon angioplasty was 94% (33 of 35 procedures). The PICC dwell time was determined for 27 PICCs and ranged from 4 to 165 days (mean, 39.6 days). Among all PICCs, 16 were removed early, resulting in an actual survival rate of 40.7% (11 of 27 PICCs). There were no significant differences in reasons for catheter removal between the stenosis and obstruction groups (p = 0.24). The dwell times for both groups were not significantly different by Kaplan-Meier analysis (p = 0.54). PICC placement after balloon angioplasty is a good treatment option for patients with unexpected central venous lesions, and offers high technical success rates. The actual survival rate was relatively lower (40.7%) than that from previous studies.

  14. Long time to diagnosis of medulloblastoma in children is not associated with decreased survival or with worse neurological outcome.

    Directory of Open Access Journals (Sweden)

    Jean-Francois Brasme

    Full Text Available BACKGROUND: The long time to diagnosis of medulloblastoma, one of the most frequent brain tumors in children, is the source of painful remorse and sometimes lawsuits. We analyzed its consequences for tumor stage, survival, and sequelae. PATIENTS AND METHODS: This retrospective population-based cohort study included all cases of pediatric medulloblastoma from a region of France between 1990 and 2005. We collected the demographic, clinical, and tumor data and analyzed the relations between the interval from symptom onset until diagnosis, initial disease stage, survival, and neuropsychological and neurological outcome. RESULTS: The median interval from symptom onset until diagnosis for the 166 cases was 65 days (interquartile range 31-121, range 3-457. A long interval (defined as longer than the median was associated with a lower frequency of metastasis in the univariate and multivariate analyses and with a larger tumor volume, desmoplastic histology, and longer survival in the univariate analysis, but not after adjustment for confounding factors. The time to diagnosis was significantly associated with IQ score among survivors. No significant relation was found between the time to diagnosis and neurological disability. In the 62 patients with metastases, a long prediagnosis interval was associated with a higher T stage, infiltration of the fourth ventricle floor, and incomplete surgical resection; it nonetheless did not influence survival significantly in this subgroup. CONCLUSIONS: We found complex and often inverse relations between time to diagnosis of medulloblastoma in children and initial severity factors, survival, and neuropsychological and neurological outcome. This interval appears due more to the nature of the tumor and its progression than to parental or medical factors. These conclusions should be taken into account in the information provided to parents and in expert assessments produced for malpractice claims.

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

    Directory of Open Access Journals (Sweden)

    Li-Wei Chao

    2009-02-01

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

  16. Relationships among the cervical mucus urea and acetone, accuracy of insemination timing, and sperm survival in Holstein cows.

    Science.gov (United States)

    Beran, J; Stádník, L; Ducháček, J; Okrouhlá, M; Doležalová, M; Kadlecová, V; Ptáček, M

    2013-11-01

    The objectives of this study were to evaluate the relationships among urea and acetone content in cows' cervical mucus (CM), its crystallization type (CT) and sperm survival (SS) after timed AI. Samples of CM were collected from 192 Holstein cows treated by Ovsynch(®) protocol. Analysis of the urea and acetone content for identification of the metabolic status, the arborization test for evaluation of insemination timing and the short-term heat test of SS for assessment of its suitability as a biological matrix were performed. The data set was analyzed by the GLM procedure using SAS(®). The results documented the existence of substantial differences in individual response to the Ovsynch(®) protocol causing insemination of 55.2% cows at an inappropriate time. The urea content was found as a possible indicator of a cow's metabolism and/or of insemination timing, concentrations of less than 500 mg/L corresponded (Pacetone content on SS were determined. The greatest values of SS were detected in cows with an expected response to precisely timed oestrus documented by the corresponding CT. Greater values of urea (>260 mg/L) and acetone (>5mg/L) negatively affected SS as well (P<0.05-0.01). The results confirmed that the accuracy of insemination timing can be affected by the metabolism intensity, just as CM quality directly influences sperm survival. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Using simulation to interpret a discrete time survival model in a complex biological system: fertility and lameness in dairy cows.

    Directory of Open Access Journals (Sweden)

    Christopher D Hudson

    Full Text Available The ever-growing volume of data routinely collected and stored in everyday life presents researchers with a number of opportunities to gain insight and make predictions. This study aimed to demonstrate the usefulness in a specific clinical context of a simulation-based technique called probabilistic sensitivity analysis (PSA in interpreting the results of a discrete time survival model based on a large dataset of routinely collected dairy herd management data. Data from 12,515 dairy cows (from 39 herds were used to construct a multilevel discrete time survival model in which the outcome was the probability of a cow becoming pregnant during a given two day period of risk, and presence or absence of a recorded lameness event during various time frames relative to the risk period amongst the potential explanatory variables. A separate simulation model was then constructed to evaluate the wider clinical implications of the model results (i.e. the potential for a herd's incidence rate of lameness to influence its overall reproductive performance using PSA. Although the discrete time survival analysis revealed some relatively large associations between lameness events and risk of pregnancy (for example, occurrence of a lameness case within 14 days of a risk period was associated with a 25% reduction in the risk of the cow becoming pregnant during that risk period, PSA revealed that, when viewed in the context of a realistic clinical situation, a herd's lameness incidence rate is highly unlikely to influence its overall reproductive performance to a meaningful extent in the vast majority of situations. Construction of a simulation model within a PSA framework proved to be a very useful additional step to aid contextualisation of the results from a discrete time survival model, especially where the research is designed to guide on-farm management decisions at population (i.e. herd rather than individual level.

  18. Time trends in population-based breast cancer survival in Estonia: analysis by age and stage.

    Science.gov (United States)

    Baburin, Aleksei; Aareleid, Tiiu; Padrik, Peeter; Valvere, Vahur; Innos, Kaire

    2014-02-01

    Survival from breast cancer (BC) in Estonia has been consistently among the lowest in Europe. The aim of this study was to examine most recent trends in BC survival in Estonia by age and stage. The trends in overall BC incidence and mortality are also shown in the paper. Estonian Cancer Registry data on all cases of BC, diagnosed in women in Estonia during 1995-2007 (n = 7424) and followed up for vital status through 2009, were used to estimate relative survival ratios (RSR). Period hybrid approach was used to obtain the most recent estimates (2005-2009). Stage was classified as localized, local/regional spread or distant. BC incidence continued to rise throughout the study period, but mortality has been in steady decline since 2000. The distribution of patients shifted towards older age and earlier stage at diagnosis. Overall age-standardized five-year RSR increased from 63% in 1995-1999 to 74% in 2005-2009. Younger age groups experienced a more rapid improvement compared to women over 60. Significant survival increase was observed for both localized and locally/regionally spread BC with five-year RSRs reaching 96% and 70% in 2005-2009, respectively; the latest five-year RSR for distant BC was 11%. Survival for T4 tumors was poor and large age difference was seen for locally/regionally spread BC. Considerable improvement in BC survival was observed over the study period. Women under 60 benefited most from both earlier diagnosis and treatment advances of locally/regionally spread cancers. However, the survival gap with more developed countries persists. Further increase in survival, but also decline in BC mortality in Estonia could be achieved by facilitating early diagnosis in all age groups, but particularly among women over 60. Investigations should continue to clarify the underlying mechanisms of the stage-specific survival deficit in Estonia.

  19. Time to adjuvant chemotherapy following colorectal cancer resection is associated with an improved survival.

    Science.gov (United States)

    Day, A R; Middleton, G; Smith, R V P; Jourdan, I C; Rockall, T A

    2014-05-01

    Multicentre randomized trials have demonstrated equivalent long-term outcomes for open and laparoscopic resection of colon cancer. Some studies have indicated a possible survival advantage in certain patients undergoing laparoscopic resection. Patients who receive adjuvant chemotherapy in improved survival. Data were collated for patients having an elective laparoscopic or open resection for non-metastatic colorectal cancer between October 2003 and December 2010 and subsequently having adjuvant chemotherapy. Survival analysis was conducted. In all, 209 patients received adjuvant chemotherapy following open (n = 76) or laparoscopic (n = 133) surgery. Median length of stay was 3 days with laparoscopic resection and 6 days with open resection (P chemotherapy was 52 with laparoscopic resection and 58 with open resection (P = 0.008). The 5-year overall survival was 89.6% in patients receiving chemotherapy in chemotherapy chemotherapy. Colorectal Disease © 2014 The Association of Coloproctology of Great Britain and Ireland.

  20. Effects of interspecific competition, predation, and their interaction on survival and development time of immature Anopheles quadrimaculatus.

    Science.gov (United States)

    Knight, Tiffany M; Chase, Jonathan M; Goss, Charles W; Knight, Jennifer J

    2004-12-01

    We examined the effect of predation by the backswimmer (Notonecta undulata; Hemiptera: Notonectidae), competition by zooplankton and snails, and both predation and competition on the survival and development time of larval Anopheles quadrimaculatus mosquitoes in experimental mesocosms. We found that both predation and interspecific competition greatly reduced the survivorship of larvae and the number of larvae emerging into adulthood. Treatments with both predators and competitors had fewer larvae transitioning among instars and into adulthood but not in an additive way. In addition, mosquito larvae in the presence of predators and competitors took two days longer to emerge than where predators and competitions were absent. Our work provides evidence that biotic interactions, such as predation and competition, can strongly regulate the number of mosquito larvae by reducing the number of larvae that survive through instars and to emergence and by increasing the generation time.

  1. [Relationships between Serum Albumin and Urea Level and the Clinical Pathological Characteristics and Survival Time in Patients with Lung Cancer].

    Science.gov (United States)

    Li, Yalun; Li, Lei; Zhang, Li; Li, Weimin

    2017-03-20

    Lung cancer is the most common malignancy and is the leading cause of cancer-related death worldwide. Thus, this disease severely threatens human health. This study aims to identify the relationships between serum albumin and urea level and the clinical pathological characteristics and survival time in patients with lung cancer. A total of 1,098 patients with lung cancer were diagnosed by pathology and tested the serum albumin and urea level in West China Hospital of Sichuan University during January 2008 to December 2013. According to the levels of albumin and urea, patients were divided into the normal level group (negative group) and abnormal level group (positive group). The differences of patients' clinical pathological characteristics and survival time in the two groups were analyzed. Differences in age, sex, histological classification, liver metastasis and pleural metastasis were statistically significant between the two groups of serum albumin (Purea. In different histological classification between the two groups of serum albumin, the median survival period of squamous cell carcinoma was 36 months and 19 monthes, adenocarcinoma was 35 months and 15 monthes, the abnormal group were all significantly lower than those in the normal group. The median survival period was no significant difference between the two groups of urea. The level of serum albumin is an important indicator for prognosis.

  2. Rat Strains Bred for Low and High Aerobic Running Capacity do not Differ in Their Survival Time to Hemorrhage

    Science.gov (United States)

    2009-12-01

    maximal oxygen consumption ( Vo2max ) was 12% greater during normoxia and 20% greater during hypoxia in the HCR vs LCR (12). This enhanced Vo2max ...mitochondria) rather than differences in cardiac output, and also occurred in the absence of differences in oxygen delivery. By generation 15, VO2max ...survival time of HCR and LCR lines to the same controlled hemorrhage. We hypothesized that a strain with improved VO2max (i.e., HCR) would demonstrate an

  3. Survival of Patients on Hemodialysis and Predictors of Mortality: a Single-Centre Analysis of Time-Dependent Factors.

    Science.gov (United States)

    Ossareh, Shahrzad; Farrokhi, Farhat; Zebarjadi, Marjan

    2016-11-01

    This study aimed to evaluate the outcome and predictors of survival in hemodialysis patients of Hasheminejad Kidney Center where a comprehensive dialysis care program has been placed since 2004. Data of 560 hemodialysis patients were used to evaluate 9-year survival rates and predictors of mortality. Cox regression models included comorbidities as well as averaged and 6-month-averaged time-dependent values of laboratory findings as independent factors. Survival rates were 91.9%, 66.0%, 46.3%, and 28.5%,  at 1, 3, 5, and 9 years, respectively, in all patients and 90.8%, 61.6%, 42.1%, and 28.0% in 395 incident patients starting hemodialysis after 2004. Adjusted survival models demonstrated age, male sex, diabetes mellitus, cardiovascular disease, and high-risk vascular access as baseline predictors of mortality, as well as averaged low hemoglobin level (hazard ratio [HR], 1.98; 95% confidence interval [CI], 1.36 to 2.90) and a single-pool KT/V patients have relatively comparable survival rates with high-profile dialysis centers. Aiming to better achieve the recommended targets, especially hemoglobin and nutritional and bone metabolism factors, should be considered for optimal dialysis outcomes.

  4. Effect of intestinal microflora on the survival time of mice exposed to lethal whole-body. gamma. irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Onoue, M.; Uchida, K.; Yokokura, T.; Takahashi, T.; Mutai, M.

    1981-11-01

    The effect of intestinal microflora on the survival time of mice exposed to 2-kR whole-body ..gamma.. irradiation was studied using germfree, monoassociated, and conventionalized ICR mice. The germfree mice were monoassociated with 1 of 11 bacterial strains, which were isolated from the fresh feces of conventional mice, 2 weeks prior to irradiation. All mice died within 3 weeks after irradiation. Monoassociation with Fusobacterium sp., Streptococcus faecalis, Escherichia coli, or Pseudomonas sp. significantly reduced the mean survival time compared to that of germfree mice. In contrast, monoassociation with Clostridium sp., Bifidobacterium pseudolongum, or Lactobacillus acidophilus significantly prolonged the mean survival time compared to that of germfree mice. This suggests that the latter organisms may perform some activity to protect the mice from radiation injury. In this histopathological autopsy examination, the main lesions were hypocellularity in hematopoietic organs and hemorrhage in various organs. Neither karyorrhexis nor desquamation of intestinal mucosal cells was observed in any mice. From these observations, it is suggested that the death of these mice was related to hematopoietic damage. Bacterial invasion into various organs was observed in conventionalized and Pseudomonas-, E. coli-, or S. faecalis-monoassociated mice but not in Clostridium-, B. pseudolongum-, L. acidophilus-, or Fusobacterium-monoassociated mice.

  5. Prognostic value of a decreased tongue strength for survival time in patients with amyotrophic lateral sclerosis

    NARCIS (Netherlands)

    Alexander Geurts; J. Weikamp; J. Hendriks; J. Schelhaas; Bert de Swart

    2012-01-01

    Decreased tongue strength (TS) might herald bulbar involvement in patients with amyotrophic lateral sclerosis (ALS) well before dysarthria or dysphagia occur, and as such might be prognostic of short survival. The purpose of this study was to investigate the prognostic value of a decreased TS, in

  6. Prognostic value of decreased tongue strength on survival time in patients with amyotrophic lateral sclerosis

    NARCIS (Netherlands)

    Weikamp, J.G.; Schelhaas, H.J.; Hendriks, J.C.M.; Swart, B.J.M. de; Geurts, A.C.H.

    2012-01-01

    Decreased tongue strength (TS) might herald bulbar involvement in patients with amyotrophic lateral sclerosis (ALS) well before dysarthria or dysphagia occur, and as such might be prognostic of short survival. The purpose of this study was to investigate the prognostic value of a decreased TS, in

  7. Genomic prediction of survival time in a population of brown laying hens showing cannibalistic behavior

    NARCIS (Netherlands)

    Alemu, Setegn W.; Calus, Mario P.L.; Muir, William M.; Peeters, Katrijn; Vereijken, Addie; Bijma, Piter

    2016-01-01

    Background: Mortality due to cannibalism causes both economic and welfare problems in laying hens. To limit mortality due to cannibalism, laying hens are often beak-trimmed, which is undesirable for animal welfare reasons. Genetic selection is an alternative strategy to increase survival and is

  8. A special case of reduced rank models for identification and modelling of time varying effects in survival analysis.

    Science.gov (United States)

    Perperoglou, Aris

    2016-12-10

    Flexible survival models are in need when modelling data from long term follow-up studies. In many cases, the assumption of proportionality imposed by a Cox model will not be valid. Instead, a model that can identify time varying effects of fixed covariates can be used. Although there are several approaches that deal with this problem, it is not always straightforward how to choose which covariates should be modelled having time varying effects and which not. At the same time, it is up to the researcher to define appropriate time functions that describe the dynamic pattern of the effects. In this work, we suggest a model that can deal with both fixed and time varying effects and uses simple hypotheses tests to distinguish which covariates do have dynamic effects. The model is an extension of the parsimonious reduced rank model of rank 1. As such, the number of parameters is kept low, and thus, a flexible set of time functions, such as b-splines, can be used. The basic theory is illustrated along with an efficient fitting algorithm. The proposed method is applied to a dataset of breast cancer patients and compared with a multivariate fractional polynomials approach for modelling time-varying effects. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  9. Meta-analysis of the effects of beta blocker on survival time in cancer patients.

    Science.gov (United States)

    Choi, Chel Hun; Song, Taejong; Kim, Tae Hyun; Choi, Jun Kuk; Park, Jin-Young; Yoon, Aera; Lee, Yoo-Young; Kim, Tae-Joong; Bae, Duk-Soo; Lee, Jeong-Won; Kim, Byoung-Gie

    2014-07-01

    This study was to elucidate the potential benefit of beta blockers on cancer survival. We comprehensively searched PubMed, Embase, and the Cochrane Library from their inception to April 2013. Two authors independently screened and reviewed the eligibility of each study and coded the participants, treatment, and outcome characteristics. The primary outcomes were overall survival (OS) and disease-free survival (DFS). Twelve studies published between 1993 and 2013 were included in the final analysis. Four papers reported results from 10 independent groups, resulting in a total of 18 comparisons based on data obtained from 20,898 subjects. Effect sizes (hazard ratios, HR) were heterogeneous, and random-effects models were used in the analyses. The meta-analysis demonstrated that beta blocker use is associated with improved OS (HR 0.79; 95 % CI 0.67-0.93; p = 0.004) and DFS (HR 0.69; 95 % CI 0.53-0.91; p = 0.009). Although statistically not significant, the effect size was greater in patients with low-stage cancer or cancer treated primarily with surgery than in patients with high-stage cancer or cancer treated primarily without surgery (HR 0.60 vs. 0.78, and 0.60 vs. 0.80, respectively). Although only two study codes were analyzed, the studies using nonselective beta blockers showed that there was no overall effect on OS (HR 0.52, 95 % CI 0.09-3.04). This meta-analysis provides evidence that beta blocker use can be associated with the prolonged survival of cancer patients, especially patients with early-stage cancer treated primarily with surgery.

  10. Fluid Regulation and Time Course of Erythropoietin during Multifactorial Strain of Austrian Special Forces Survival Training

    Science.gov (United States)

    2001-03-01

    It seems that EPO production and release is diminished by nutritional factors, i.e. mainly caloric intake, during prolonged physical strain. In the...sign for a haemolytic anaemia with impaired erythropoiesis (20) which would be in line with decreased EPO values found during the survival training...total body iron stores. The classical biochemical constellation of an haemolytic anaemia might be misleading under the described conditions. The body

  11. Bayesian Variable Selection in High Dimensional Survival Time Cancer Genomic Datasets using Nonlocal Priors

    OpenAIRE

    Nikooienejad, Amir; Wang, Wenyi; Johnson, Valen E.

    2017-01-01

    Variable selection in high dimensional cancer genomic studies has become very popular in the past decade, due to the interest in discovering significant genes pertinent to a specific cancer type. Censored survival data is the main data structure in such studies and performing variable selection for such data type requires certain methodology. With recent developments in computational power, Bayesian methods have become more attractive in the context of variable selection. In this article we i...

  12. Managing hospitals in turbulent times: do organizational changes improve hospital survival?

    Science.gov (United States)

    Lee, S Y; Alexander, J A

    1999-10-01

    To examine (1) the degree to which organizational changes affected hospital survival; (2) whether core and peripheral organizational changes affected hospital survival differently; and (3) how simultaneous organizational changes affected hospital survival. AHA Hospital Surveys, the Area Resource File, and the AHA Hospital Guides, Part B: Multihospital Systems. The study employed a longitudinal panel design. We followed changes in all community hospitals in the continental United States from 1981 through 1994. The dependent variable, hospital closure, was examined as a function of multiple changes in a hospital's core and peripheral structures as well as the hospital's organizational and environmental characteristics. Cox regression models were used to test the expectations that core changes increased closure risk while peripheral changes decreased such risk, and that simultaneous core and peripheral changes would lead to higher risk of closure. Results indicated more peripheral than core changes in community hospitals. Overall, findings contradicted our expectations. Change in specialty, a core change, was beneficial for hospitals, because it reduced closure risk. The two most frequent peripheral changes, downsizing and leadership change, were positively associated with closure. Simultaneous organizational changes displayed a similar pattern: multiple core changes reduced closure risk, while multiple peripheral changes increased the risk. These patterns held regardless of the level of uncertainty in hospital environments. Organizational changes are not all beneficial for hospitals, suggesting that hospital leaders should be both cautious and selective in their efforts to turn their hospitals around.

  13. Simple parametric survival analysis with anonymized register data: A cohort study with truncated and interval censored event and censoring times

    Directory of Open Access Journals (Sweden)

    Kristiansen Ivar S

    2011-08-01

    Full Text Available Abstract Background To preserve patient anonymity, health register data may be provided as binned data only. Here we consider as example, how to estimate mean survival time after a diagnosis of metastatic colorectal cancer from Norwegian register data on time to death or censoring binned into 30 day intervals. All events occurring in the first three months (90 days after diagnosis were removed to achieve comparability with a clinical trial. The aim of the paper is to develop and implement a simple, and yet flexible method for analyzing such interval censored and truncated data. Methods Considering interval censoring a missing data problem, we implement a simple multiple imputation strategy that allows flexible sensitivity analyses with respect to the shape of the censoring distribution. To allow identification of appropriate parametric models, a χ2-goodness-of-fit test--also imputation based--is derived and supplemented with diagnostic plots. Uncertainty estimates for mean survival times are obtained via a simulation strategy. The validity and statistical efficiency of the proposed method for varying interval lengths is investigated in a simulation study and compared with simpler alternatives. Results Mean survival times estimated from the register data ranged from 1.2 (SE = 0.09 to 3.2 (0.31 years depending on period of diagnosis and choice of parametric model. The shape of the censoring distribution within intervals did generally not influence results, whereas the choice of parametric model did, even when different models fit the data equally well. In simulation studies both simple midpoint imputation and multiple imputation yielded nearly unbiased analyses (relative biases of -0.6% to 9.4% and confidence intervals with near-nominal coverage probabilities (93.4% to 95.7% for censoring intervals shorter than six months. For 12 month censoring intervals, multiple imputation provided better protection against bias, and coverage probabilities

  14. Time outs

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000756.htm Time outs To use the sharing features on this ... children, 2 to 12 years old. Why Does Time out Work? When you put children in time ...

  15. Associations of red and processed meat with survival after colorectal cancer and differences according to timing of dietary assessment.

    Science.gov (United States)

    Carr, Prudence R; Jansen, Lina; Walter, Viola; Kloor, Matthias; Roth, Wilfried; Bläker, Hendrik; Chang-Claude, Jenny; Brenner, Hermann; Hoffmeister, Michael

    2016-01-01

    Little is known about the prognostic impact of red and processed meat intake or about changes in consumption after a diagnosis of colorectal cancer (CRC). We investigated associations of baseline red and processed meat with survival outcomes and explored changes in intake among CRC survivors 5 y after diagnosis. A total of 3122 patients diagnosed with CRC between 2003 and 2010 were followed for a median of 4.8 y [DACHS (Darmkrebs: Chancen der Verhütung durch Screening) study]. Patients provided information on diet and other factors in standardized questionnaires at baseline and at the 5-y follow-up. Cox proportional hazards regression models were used to estimate HRs and 95% CIs. Among patients with stage I-III CRC, baseline red and processed meat intake was not associated with overall (>1 time/d compared with processed meat at the 5-y follow-up than at baseline (concordance rate: 39%; κ-value: 0.10; 95% CI: 0.07, 0.13). Our findings suggest that baseline red and processed meat intake is not associated with poorer survival among patients with CRC. The potential interaction with KRAS mutation status warrants further evaluation. Major changes in consumption measured at the 5-y follow-up may have had an impact on our survival estimates. © 2016 American Society for Nutrition.

  16. Diabetes, hypertension and hyperlipidemia: prevalence over time and impact on long-term survival after liver transplantation.

    Science.gov (United States)

    Parekh, J; Corley, D A; Feng, S

    2012-08-01

    With increasing short-term survival, the transplant community has turned its focus to delineating the impact of medical comorbidities on long-term outcomes. Unfortunately, conditions such as diabetes, hypertension and hyperlipidemia are difficult to track and often managed outside of the transplant center by primary care providers. We collaborated with Kaiser Permanente Northern California to create a database of 598 liver transplant recipients, which incorporates diagnostic codes along with laboratory and pharmacy data. Specifically, we determined the prevalence of diabetes, hypertension and hyperlipidemia both before and after transplant and evaluated the influence of disease duration as a time-dependent covariate on posttransplant survival. The prevalence of these comorbidities increased steadily from the time of transplant to 7 years after transplant. The estimated risk for all-cause mortality (hazard ratio = 1.07 per year increment, 95% CI 1.01-1.13, p hyperlipidemia. Greater attention to management of diabetes may mitigate its negative impact on long-term survival in liver transplant recipients. © Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.

  17. ENTREPRENEURSHIP IN TIMES OF ECONOMIC AND FINANCIAL CRISES, METHODS OF ADAPTATION AND SURVIVAL.

    Directory of Open Access Journals (Sweden)

    Radu Oprea

    2011-12-01

    Full Text Available This paper shows the main results of a research activity conducted in the South – East region of Romania during November 2009, over 117 small and medium-sized enterprises. The results help to better explain some of the social problems that have been generated in the region as a snow ball effect, due to the economic and financial crisis. The research has revealed the following:The majority of the employees of the companies that were interviewed do not participate in training courses related to project management and personal development. However, company administrators consider that such courses are useful to increase competitiveness in times of economic and financial crises. Personnel under 40 years of age suffer from a lack of professional training and dedication to job requirements. Companies have expressed an interest in accessing European Union funding. However, they do not have complete information that would allow them to start a project and finalize it. This lack of information is mainly due to lack of access to specialists who would write the projects and submit them. The majority of entrepreneurs consider they cannot write the projects themselves but on the other hand they do not have access to consulting companies or other organizations that could help them. Their main information source is the mass-media.As a result, companies have adjusted to the effects of the economic crisis, diminishing their activity and laying off people, decreasing the running expenses and stopping investing in their development.

  18. Time-out/Time-in

    DEFF Research Database (Denmark)

    Bødker, Mads; Gimpel, Gregory; Hedman, Jonas

    2014-01-01

    time-in and time-out use. Time-in technology use coincides and co-exists within the flow of ordinary life, while time-out use entails ‘taking time out’ of everyday life to accomplish a circumscribed task or engage reflectively in a particular experience. We apply a theoretically informed grounded...

  19. Wind speed during migration influences the survival, timing of breeding, and productivity of a neotropical migrant, Setophaga petechia.

    Directory of Open Access Journals (Sweden)

    Anna Drake

    Full Text Available Over the course of the annual cycle, migratory bird populations can be impacted by environmental conditions in regions separated by thousands of kilometers. We examine how climatic conditions during discrete periods of the annual cycle influence the demography of a nearctic-neotropical migrant population of yellow warblers (Setophaga petechia, that breed in western Canada and overwinter in Mexico. We demonstrate that wind conditions during spring migration are the best predictor of apparent annual adult survival, male arrival date, female clutch initiation date and, via these timing effects, annual productivity. We find little evidence that conditions during the wintering period influence breeding phenology and apparent annual survival. Our study emphasizes the importance of climatic conditions experienced by migrants during the migratory period and indicates that geography may play a role in which period most strongly impacts migrant populations.

  20. Influence of application sequence and timing of eugenol and lauric arginate (LAE) on survival of spoilage organisms.

    Science.gov (United States)

    Manrique, Yudith; Gibis, Monika; Schmidt, Herbert; Weiss, Jochen

    2017-06-01

    The effectiveness of sequential applications of the antimicrobials eugenol and lauric arginate (LAE) was investigated against Staphylococcus carnosus, Listeria innocua, Escherichia coli K12, and Pseudomonas fluorescens. The antimicrobials were applied simultaneously at half of their minimum lethal concentrations (MLC) or sequentially at t = 0 h and t = 3, 4, 6 or 8 h. Bacterial survival was determined by direct plate counts. Survivals kinetic were fitted to a growth and mortality model to obtain characteristic parameters that described time-dependent changes from growth to mortality or vice versa. The most effective was a simultaneous exposure of both antimicrobials to the spoilage organisms at the beginning of the incubation period. Efficiency decreases depending on order and timing of the two antimicrobials were observed upon sequential treatments. These were most effective when antimicrobials where applied within a short time period (3-4 h) and when eugenol was first applied against S. carnosus and P. fluorescens. No sequence effects were observed for L. innocua, and sequential treatments proved to be ineffective against E. coli K12. These results were attributed to cells adapting to the first applied antimicrobial. In some cases, this provided protection against the second antimicrobial rendering the overall treatment less effective. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Relationships between Serum Albumin and Urea Level and the Clinical Pathological Characteristics and Survival Time in Patients with Lung Cancer

    Directory of Open Access Journals (Sweden)

    Yalun LI

    2017-03-01

    Full Text Available Background and objective Lung cancer is the most common malignancy and is the leading cause of cancer-related death worldwide. Thus, this disease severely threatens human health. This study aims to identify the relationships between serum albumin and urea level and the clinical pathological characteristics and survival time in patients with lung cancer. Methods A total of 1,098 patients with lung cancer were diagnosed by pathology and tested the serum albumin and urea level in West China Hospital of Sichuan University during January 2008 to December 2013. According to the levels of albumin and urea, patients were divided into the normal level group (negative group and abnormal level group (positive group. The differences of patients' clinical pathological characteristics and survival time in the two groups were analyzed. Results Differences in age, sex, histological classification, liver metastasis and pleural metastasis were statistically significant between the two groups of serum albumin (P<0.05. Differences in age, intrapulmonary metastasis of 312 patients of squamous cell carcinoma and differences in age, sex, stages, pleural metastasis of 612 patients of adenocarcinoma between the two groups of serum albumin (P<0.05. There were no significant differences between the two groups of urea. In different histological classification between the two groups of serum albumin, the median survival period of squamous cell carcinoma was 36 months and 19 monthes, adenocarcinoma was 35 months and 15 monthes, the abnormal group were all significantly lower than those in the normal group. The median survival period was no significant difference between the two groups of urea. Conclusion The level of serum albumin is an important indicator for prognosis.

  2. Reinventing Time

    Science.gov (United States)

    Technology Teacher, 2004

    2004-01-01

    What do planet Earth, a swinging pendulum, a quartz crystal, and a Cesium atom have in common? They have all been used by humans to measure time. They represent humanity's progress through time in measuring time itself. But what is it, really, that humans set out to measure? Before time could be measured, somebody had to decide what to actually…

  3. Applied the additive hazard model to predict the survival time of patient with diffuse large B- cell lymphoma and determine the effective genes, using microarray data

    Directory of Open Access Journals (Sweden)

    Arefa Jafarzadeh Kohneloo

    2015-09-01

    Full Text Available Background: Recent studies have shown that effective genes on survival time of cancer patients play an important role as a risk factor or preventive factor. Present study was designed to determine effective genes on survival time for diffuse large B-cell lymphoma patients and predict the survival time using these selected genes. Materials & Methods: Present study is a cohort study was conducted on 40 patients with diffuse large B-cell lymphoma. For these patients, 2042 gene expression was measured. In order to predict the survival time, the composition of the semi-parametric additive survival model with two gene selection methods elastic net and lasso were used. Two methods were evaluated by plotting area under the ROC curve over time and calculating the integral of this curve. Results: Based on our findings, the elastic net method identified 10 genes, and Lasso-Cox method identified 7 genes. GENE3325X increased the survival time (P=0.006, Whereas GENE3980X and GENE377X reduced the survival time (P=0.004. These three genes were selected as important genes in both methods. Conclusion: This study showed that the elastic net method outperformed the common Lasso method in terms of predictive power. Moreover, apply the additive model instead Cox regression and using microarray data is usable way for predict the survival time of patients.

  4. Efficacy of Re-188-labelled sulphur colloid on prolongation of survival time in melanoma-bearing animals

    Energy Technology Data Exchange (ETDEWEB)

    Chen, F.D.; Hsieh, B.T. E-mail: bthsieh@iner.gov.tw; Wang, H.E.; Ou, Y.H.; Yang, W.K.; Whang-Peng, J.; Liu, R.S.; Knapp, F.F.; Ting, G.; Yen, S.H

    2001-10-01

    In this study, the effectiveness of a {sup 188}Re labeled sulfur colloid with two particle size ranges was used to evaluate the effectiveness of this agent on melanoma tumors in mice in terms of animal lifespan. Methods: Two separate group of animals were used for investigating biodistribution and survival time. A total of 188 B16F10-melanoma-bearing BDF{sub 1} mice were injected intraperitoneally with 3.7 MBq (0.1mCi)/2mL of radiolabeled sulfur colloid ten days after intraperitoneal inoculation of 5x10{sup 5} B16F10 melanoma cells/2ml. For group 1, 30 mice were sacrificed at 1, 4, 24, 48 and 72 hours for biodistribution studies. In group 2, 158 mice were divided into 9 groups (n=16{approx}18/groups)each receiving respectively tumor alone, tumor with normal saline, cold colloid or hot colloid with 16, 23, 31, 46, 62, or 124 MBq activity. Each of these colloid groups was further divided into two groups, one receiving smaller particle sizes (<3{mu}m:80.4 {+-}7.2%, colloid 1) and the other receiving larger particle sizes (<3{mu}m:12.3{+-}1.0%, colloid 2). The animals were checked daily until death and their survival recorded. Results: Colloid 2 showed higher accumulation in almost all tissues, the highest accumulation organ was tumor ({approx} 40%), then spleen ({approx}20%), stomach ({approx}15%), diaphragm ({approx}3%), and liver ({approx}2%). There was a significant increase in survival time with increasing amount of the larger-particle-size colloid. Administered levels of 16-31 MBq/mouse were most efficacious and with higher amounts the survival times decreased significantly below that of the controls. There was a significant difference in the dose-response curves for the two preparations. Protection factors (1/Relative-risk) of nearly 5 were achieved using the larger colloid size, and nearly 30 using the smaller colloid size. An amount of 16-31 MBq of the colloid 2 was the optimal activity in these studies. On the one hand, the survival data agreed well with the

  5. The Association between Phase Angle of Bioelectrical Impedance Analysis and Survival Time in Advanced Cancer Patients: Preliminary Study.

    Science.gov (United States)

    Lee, So Yeon; Lee, Yong Joo; Yang, Jung-Hwa; Kim, Chul-Min; Choi, Whan-Seok

    2014-09-01

    A frequent manifestation of advanced cancer patients is malnutrition, which is correlated with poor prognosis and high mortality. Bioelectrical impedance analysis (BIA) is an easy-to-use and non-invasive technique to evaluate changes in body composition and nutritional status. We investigated BIA-derived phase angle as a prognostic indicator for survival in advanced cancer patients. Twenty-eight patients treated at the hospice center of Seoul St. Mary's Hospital underwent BIA measurements from January, 2013 to May, 2013. We also evaluated palliative prognostic index (PPI) and palliative performance scale to compare with the prognostic value of phase angle. Cox's proportional hazard models were constructed to evaluate the prognostic effect of phase angle. The Kaplan Meier method was used to calculate survival. Using univariate Cox analysis, phase angle (hazard ratio [HR], 0.61/per degree increase; 95% confidence interval [CI], 0.42 to 0.89; P = 0.010), PPI (HR, 1.21; 95% CI, 1.00 to 1.47; P = 0.048) were found to be significantly associated with survival. Adjusting age, PPI, body mass index, phase angle significantly showed association with survival in multivariate analysis (HR, 0.64/per degree increase; 95% CI, 0.42 to 0.95; P = 0.028). Survival time of patients with phase angle ≥ 4.4° was longer than patients with phase angle < 4.4° (log rank, 6.208; P-value = 0.013). Our data suggest BIA-derived phase angle may serve as an independent prognostic indicator in advanced cancer patients.

  6. Vitamin D Depletion in Pregnancy Decreases Survival Time, Oxygen Saturation, Lung Weight and Body Weight in Preterm Rat Offspring.

    Directory of Open Access Journals (Sweden)

    Sine Lykkedegn

    Full Text Available Animal studies suggest a role of vitamin D in fetal lung development although not studied in preterm animals. We tested the hypothesis that vitamin D depletion aggravates respiratory insufficiency in preterm rat offspring. Furthermore, the effects of vitamin D depletion on growth and lung surfactant were investigated. Female Sprague-Dawley rats were randomly assigned low vitamin D (VDL or control diet before mating and followed with serum 25-hydroxyvitamin D (s-25(OHD determinations. After cesarean section at gestational day 19 (E19 or day 22 (E22, placental weight, birth weight, crown-rump-length (CRL, oxygenation (SaO2 at 30 min and survival time were recorded. The pup lungs were analyzed for phospholipid levels, surfactant protein A-D mRNA and the expression of the vitamin D receptor (VDR. S-25(OHD was significantly lower in the VDL group at cesarean section (12 vs. 30nmol/L, p<0.0001. Compared to the controls, E19 VDL pups had lower birth weight (2.13 vs. 2.29g, p<0.001, lung weight (0.09 vs. 0.10g, p = 0.002, SaO2 (54% vs. 69%, p = 0.002 as well as reduced survival time (0.50 vs. 1.25h, p<0.0001. At E22, the VDL-induced pulmonary differences were leveled out, but VDL pups had lower CRL (4.0 vs. 4.5cm, p<0.0001. The phospholipid levels and the surfactant protein mRNA expression did not differ between the dietary groups. In conclusion, Vitamin D depletion led to lower oxygenation and reduced survival time in the preterm offspring, associated with reduced lung weight and birth weight. Further studies of vitamin D depletion in respiratory insufficiency in preterm neonates are warranted.

  7. Differential presentation and survival of de novo and recurrent metastatic breast cancer over time: 1990-2010.

    Science.gov (United States)

    Malmgren, Judith A; Mayer, Musa; Atwood, Mary K; Kaplan, Henry G

    2017-10-16

    Differences in de novo (dnMBC) and recurrent metastatic breast cancer (rMBC) presentation and survival over time have not been adequately described. A retrospective cohort study, 1990-2010, with follow up through 2015 of dnMBC patients (stage IV at diagnosis) and rMBC patients with subsequent distant metastatic recurrence (stage I-III initial diagnosis) [dnMBC = 247, rMBC = 911)]. Analysis included Chi squared tests of categorical variables, Kaplan-Meier survival estimates, and Cox proportional adjusted hazard ratios (HzR) and 95% confidence intervals (CI). Disease specific survival (DSS) was time from diagnosis or distant recurrence to BC death. Over time, 1990-1998, 1999-2004, and 2005-2010, dnMBC incidence was constant (3%) and rMBC incidence decreased [18% to 7% (p negative breast cancer (HR-negative/HER2-negative) (p = 0.049). Five-year dnMBC DSS was 44% vs. 21% for rMBC (p year dnMBC DSS improved over time [28% to 55% (p = 0.008)] and rMBC worsened [23% to 13%, p = 0.065)]. Worse DSS was associated with HR-negative status (HzR = 1.63; 1.41, 1.89), rMBC (HzR = 1.88; 1.58, 2.23), older age (70 +) (HzR = 1.88; 1.58, 2.24), > 1 distant metastases (HzR 1.39; 1.20, 1.62), and visceral dominant disease (HzR 1.22; 1.05, 1.43). After 1998, HER2-positive disease was associated with better DSS (HzR = 0.72, 95% CI 0.56, 0.93). Factors associated with the widening survival gap and non-equivalence between dnMBC and rMBC and decreased rMBC incidence warrant further study.

  8. Evaluation of the Risk of Relapse in Classical Hodgkin Lymphoma at Event-Free Survival Time Points and Survival Comparison With the General Population in British Columbia.

    Science.gov (United States)

    Hapgood, Greg; Zheng, Yvonne; Sehn, Laurie H; Villa, Diego; Klasa, Richard; Gerrie, Alina S; Shenkier, Tamara; Scott, David W; Gascoyne, Randy D; Slack, Graham W; Parsons, Christina; Morris, James; Pickles, Tom; Connors, Joseph M; Savage, Kerry J

    2016-07-20

    Studies in classical Hodgkin lymphoma (cHL) typically measure the time to events from diagnosis. We evaluated the risk of relapse at event-free survival time points in cHL and compared the risk of death to expected mortality rates in British Columbia (BC). The BC Cancer Agency Lymphoid Cancer Database was screened to identify all patients age 16 to 69 years diagnosed with cHL between 1989 and 2012 treated with the chemotherapy regimen of doxorubicin, bleomycin, vinblastine, and dacarbazine (or equivalent). We compared the observed mortality to the general population using age-, sex-, and calendar period-generated expected mortality rates from BC life-tables. Relative survival was calculated using a conditional approach and expressed as a standardized mortality ratio of observed-to-expected deaths. One thousand four hundred two patients were identified; 749 patients were male (53%), the median age was 32 years, and 68% had advanced-stage disease. The median follow-up time was 8.4 years. Seventy-two percent of relapses occurred within the first 2 years of diagnosis. For all patients, the 5-year risk of relapse from diagnosis was 18.1% but diminished to 5.6% for patients remaining event free at 2 years. For advanced-stage patients who were event free at 2 years, the 5-year risk of relapse was only 7.6%, and for those who were event free at 3 years, it was comparable to that of limited-stage patients (4.1% v 2.5%, respectively; P = .07). Furthermore, international prognostic score ≥ 4 and bulky disease were no longer prognostic in patients who were event free at 1 year. Although the relative survival improved as patients remained in remission, it did not normalize compared with the general population. Patients with cHL who are event free at 2 years have an excellent outcome regardless of baseline prognostic factors. All patients with cHL had an enduring increased risk of death compared with the general population. © 2016 by American Society of Clinical Oncology.

  9. Time change

    DEFF Research Database (Denmark)

    Veraart, Almut; Winkel, Matthias

    2010-01-01

    The mathematical operation of time-changing continuous-time stochastic processes can be regarded as a standard method for building financial models. We briefly review the theory on time-changed stochastic processes and relate them to stochastic volatility models in finance. Popular models......, including time-changed Lévy processes, where the time-change process is given by a subordinator or an absolutely continuous time change, are presented. Finally, we discuss the potential and the limitations of using such processes for constructing multivariate financial models....

  10. Genetic relationship of discrete-time survival with fertility and production in dairy cattle using bivariate models

    Directory of Open Access Journals (Sweden)

    Alenda Rafael

    2007-07-01

    Full Text Available Abstract Bivariate analyses of functional longevity in dairy cattle measured as survival to next lactation (SURV with milk yield and fertility traits were carried out. A sequential threshold-linear censored model was implemented for the analyses of SURV. Records on 96 642 lactations from 41 170 cows were used to estimate genetic parameters, using animal models, for longevity, 305 d-standardized milk production (MY305, days open (DO and number of inseminations to conception (INS in the Spanish Holstein population; 31% and 30% of lactations were censored for DO and INS, respectively. Heritability estimates for SURV and MY305 were 0.11 and 0.27 respectively; while heritability estimates for fertility traits were lower (0.07 for DO and 0.03 for INS. Antagonist genetic correlations were estimated between SURV and fertility (-0.78 and -0.54 for DO and INS, respectively or production (-0.53 for MY305, suggesting reduced functional longevity with impaired fertility and increased milk production. Longer days open seems to affect survival more than increased INS. Also, high productive cows were more problematic, less functional and more liable to being culled. The results suggest that the sequential threshold model is a method that might be considered at evaluating genetic relationship between discrete-time survival and other traits, due to its flexibility.

  11. Desiccation survival time for eggs of a widespread and invasive Australian mosquito species, Aedes (Finlaya) notoscriptus (Skuse).

    Science.gov (United States)

    Faull, K J; Webb, C; Williams, C R

    2016-06-01

    The Australian native mosquito Aedes (Finlaya) notoscriptus (Skuse) is closely associated with natural and artificial water holding receptacles. Eggs are laid in habitats where they are exposed to drying conditions as water levels fluctuate. Withstanding desiccation enables survival in challenging environments and increases the potential for establishment in non-native habitats. Until now, the desiccation resistance of Ae. notoscriptus eggs has been unknown despite the historical invasive success of this important dog heartworm and arbovirus vector. Viability and mean survival times of eggs from two Ae. notoscriptus populations (metropolitan areas of Sydney, NSW and Adelaide, SA) were evaluated, with eggs stored under three dryness conditions for up to 367 days. Our results revealed that Ae. notoscriptus eggs can withstand desiccation for extended periods, under a variety of conditions, with approximately 9-13% egg viability recorded after one year. This prolonged egg survival reflects the widespread distribution of this mosquito in Australia and its history of incursions and subsequent establishment in non-native habitats. Differences in mean egg volume were recorded in addition to significantly different egg length to width ratios for the two populations, which may reflect adaptation to biotope of origin and an associated likelihood of drought and drying conditions. The results of this study suggest that the desiccation resistant eggs of Ae. notoscriptus make this species highly adaptable, increasing the risk of movement to non-endemic regions of the world. © 2016 The Society for Vector Ecology.

  12. Vitamin D Depletion in Pregnancy Decreases Survival Time, Oxygen Saturation, Lung Weight and Body Weight in Preterm Rat Offspring.

    Science.gov (United States)

    Lykkedegn, Sine; Sorensen, Grith Lykke; Beck-Nielsen, Signe Sparre; Pilecki, Bartosz; Duelund, Lars; Marcussen, Niels; Christesen, Henrik Thybo

    2016-01-01

    Animal studies suggest a role of vitamin D in fetal lung development although not studied in preterm animals. We tested the hypothesis that vitamin D depletion aggravates respiratory insufficiency in preterm rat offspring. Furthermore, the effects of vitamin D depletion on growth and lung surfactant were investigated. Female Sprague-Dawley rats were randomly assigned low vitamin D (VDL) or control diet before mating and followed with serum 25-hydroxyvitamin D (s-25(OH)D) determinations. After cesarean section at gestational day 19 (E19) or day 22 (E22), placental weight, birth weight, crown-rump-length (CRL), oxygenation (SaO2) at 30 min and survival time were recorded. The pup lungs were analyzed for phospholipid levels, surfactant protein A-D mRNA and the expression of the vitamin D receptor (VDR). S-25(OH)D was significantly lower in the VDL group at cesarean section (12 vs. 30nmol/L, plung weight (0.09 vs. 0.10g, p = 0.002), SaO2 (54% vs. 69%, p = 0.002) as well as reduced survival time (0.50 vs. 1.25h, plung weight and birth weight. Further studies of vitamin D depletion in respiratory insufficiency in preterm neonates are warranted.

  13. Instrumental variables estimation of exposure effects on a time-to-event endpoint using structural cumulative survival models.

    Science.gov (United States)

    Martinussen, Torben; Vansteelandt, Stijn; Tchetgen Tchetgen, Eric J; Zucker, David M

    2017-12-01

    The use of instrumental variables for estimating the effect of an exposure on an outcome is popular in econometrics, and increasingly so in epidemiology. This increasing popularity may be attributed to the natural occurrence of instrumental variables in observational studies that incorporate elements of randomization, either by design or by nature (e.g., random inheritance of genes). Instrumental variables estimation of exposure effects is well established for continuous outcomes and to some extent for binary outcomes. It is, however, largely lacking for time-to-event outcomes because of complications due to censoring and survivorship bias. In this article, we make a novel proposal under a class of structural cumulative survival models which parameterize time-varying effects of a point exposure directly on the scale of the survival function; these models are essentially equivalent with a semi-parametric variant of the instrumental variables additive hazards model. We propose a class of recursive instrumental variable estimators for these exposure effects, and derive their large sample properties along with inferential tools. We examine the performance of the proposed method in simulation studies and illustrate it in a Mendelian randomization study to evaluate the effect of diabetes on mortality using data from the Health and Retirement Study. We further use the proposed method to investigate potential benefit from breast cancer screening on subsequent breast cancer mortality based on the HIP-study. © 2017, The International Biometric Society.

  14. Incubation media affect the survival, pathway and time of embryo development in Neotropical annual fish Austrolebias nigrofasciatus (Rivulidae).

    Science.gov (United States)

    da Fonseca, A P; Volcan, M V; Robaldo, R B

    2018-01-01

    To analyse the survival, pathway and time of embryo development in the annual fish Austrolebias nigrofasciatus eggs were monitored in four liquid media and two damp media under experimental conditions for 130 days until their development was complete. Eggs kept in the same breeding water from oviposition remained in diapause I (DI) during all experiments. In constrast, up to the stage prior to entering diapause II (DII), the other media had no influence on development. Embryos at this stage (DII), however, show longer development time when treated in medium with water and powdered coconut shell so that about 80% of embryos remained in DII at 100 days. In contrast, all other treatments had a significantly lower proportion of embryos remaining in DII. When treated with Yamamoto's solution in humid media, embryos showed the fastest development. The first fully developed embryos (DIII) were seen at 27 days after oviposition. It took an average of 46-58 days for 50% of eggs in each treatment to reach DIII. Compared with other studies, survival in all incubation media was high at between 70 and 98%. Taken together, it can be concluded that all incubation media were found to be viable for maintaining embryos. Altering developmental trajectories through the manipulation of diapauses in different media makes this species a potential model organism for laboratory studies. © 2017 The Fisheries Society of the British Isles.

  15. A comparative study of machine learning methods for time-to-event survival data for radiomics risk modelling.

    Science.gov (United States)

    Leger, Stefan; Zwanenburg, Alex; Pilz, Karoline; Lohaus, Fabian; Linge, Annett; Zöphel, Klaus; Kotzerke, Jörg; Schreiber, Andreas; Tinhofer, Inge; Budach, Volker; Sak, Ali; Stuschke, Martin; Balermpas, Panagiotis; Rödel, Claus; Ganswindt, Ute; Belka, Claus; Pigorsch, Steffi; Combs, Stephanie E; Mönnich, David; Zips, Daniel; Krause, Mechthild; Baumann, Michael; Troost, Esther G C; Löck, Steffen; Richter, Christian

    2017-10-16

    Radiomics applies machine learning algorithms to quantitative imaging data to characterise the tumour phenotype and predict clinical outcome. For the development of radiomics risk models, a variety of different algorithms is available and it is not clear which one gives optimal results. Therefore, we assessed the performance of 11 machine learning algorithms combined with 12 feature selection methods by the concordance index (C-Index), to predict loco-regional tumour control (LRC) and overall survival for patients with head and neck squamous cell carcinoma. The considered algorithms are able to deal with continuous time-to-event survival data. Feature selection and model building were performed on a multicentre cohort (213 patients) and validated using an independent cohort (80 patients). We found several combinations of machine learning algorithms and feature selection methods which achieve similar results, e.g. C-Index = 0.71 and BT-COX: C-Index = 0.70 in combination with Spearman feature selection. Using the best performing models, patients were stratified into groups of low and high risk of recurrence. Significant differences in LRC were obtained between both groups on the validation cohort. Based on the presented analysis, we identified a subset of algorithms which should be considered in future radiomics studies to develop stable and clinically relevant predictive models for time-to-event endpoints.

  16. Urban Times

    DEFF Research Database (Denmark)

    Nielsen, Morten

    2017-01-01

    This is a proposed special issue with six thematic articles by different contributors on 'urban times' edited by me.......This is a proposed special issue with six thematic articles by different contributors on 'urban times' edited by me....

  17. Expectation-maximization algorithms for learning a finite mixture of univariate survival time distributions from partially specified class values

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Youngrok [Iowa State Univ., Ames, IA (United States)

    2013-05-15

    Heterogeneity exists on a data set when samples from di erent classes are merged into the data set. Finite mixture models can be used to represent a survival time distribution on heterogeneous patient group by the proportions of each class and by the survival time distribution within each class as well. The heterogeneous data set cannot be explicitly decomposed to homogeneous subgroups unless all the samples are precisely labeled by their origin classes; such impossibility of decomposition is a barrier to overcome for estimating nite mixture models. The expectation-maximization (EM) algorithm has been used to obtain maximum likelihood estimates of nite mixture models by soft-decomposition of heterogeneous samples without labels for a subset or the entire set of data. In medical surveillance databases we can find partially labeled data, that is, while not completely unlabeled there is only imprecise information about class values. In this study we propose new EM algorithms that take advantages of using such partial labels, and thus incorporate more information than traditional EM algorithms. We particularly propose four variants of the EM algorithm named EM-OCML, EM-PCML, EM-HCML and EM-CPCML, each of which assumes a specific mechanism of missing class values. We conducted a simulation study on exponential survival trees with five classes and showed that the advantages of incorporating substantial amount of partially labeled data can be highly signi cant. We also showed model selection based on AIC values fairly works to select the best proposed algorithm on each specific data set. A case study on a real-world data set of gastric cancer provided by Surveillance, Epidemiology and End Results (SEER) program showed a superiority of EM-CPCML to not only the other proposed EM algorithms but also conventional supervised, unsupervised and semi-supervised learning algorithms.

  18. Estimation of total genetic effects for survival time in crossbred laying hens showing cannibalism, using pedigree or genomic information.

    Science.gov (United States)

    Brinker, T; Raymond, B; Bijma, P; Vereijken, A; Ellen, E D

    2017-02-01

    Mortality of laying hens due to cannibalism is a major problem in the egg-laying industry. Survival depends on two genetic effects: the direct genetic effect of the individual itself (DGE) and the indirect genetic effects of its group mates (IGE). For hens housed in sire-family groups, DGE and IGE cannot be estimated using pedigree information, but the combined effect of DGE and IGE is estimated in the total breeding value (TBV). Genomic information provides information on actual genetic relationships between individuals and might be a tool to improve TBV accuracy. We investigated whether genomic information of the sire increased TBV accuracy compared with pedigree information, and we estimated genetic parameters for survival time. A sire model with pedigree information (BLUP) and a sire model with genomic information (ssGBLUP) were used. We used survival time records of 7290 crossbred offspring with intact beaks from four crosses. Cross-validation was used to compare the models. Using ssGBLUP did not improve TBV accuracy compared with BLUP which is probably due to the limited number of sires available per cross (~50). Genetic parameter estimates were similar for BLUP and ssGBLUP. For both BLUP and ssGBLUP, total heritable variance (T(2) ), expressed as a proportion of phenotypic variance, ranged from 0.03 ± 0.04 to 0.25 ± 0.09. Further research is needed on breeding value estimation for socially affected traits measured on individuals kept in single-family groups. © 2016 The Authors. Journal of Animal Breeding and Genetics Published by Blackwell Verlag GmbH.

  19. Managing time.

    Science.gov (United States)

    Wachs, J E

    1993-06-01

    Managing time puts the occupational health nurse manager in control of health services and personal goals. Articulating those goals and appropriately delegating some of the outcomes needed to meet those goals should result in accomplishing the goals in less time. Strategies to control time expenditures on a daily basis include developing a "to do" list, avoiding procrastination, time wasters, and paper shuffling, creating an environment conducive to work, and rewarding self and staff for a job well done.

  20. Assessment of chronic effects of tebuconazole on survival, reproduction and growth of Daphnia magna after different exposure times.

    Science.gov (United States)

    Sancho, E; Villarroel, M J; Ferrando, M D

    2016-02-01

    The effect of the fungicide tebuconazole (0.41, 0.52, 0.71 and 1.14mg/L) on survival, reproduction and growth of Daphnia magna organisms was monitored using 14 and 21 days exposure tests. A third experiment was performed by exposing D. magna to the fungicide for 14 days followed by 7 days of recovery (14+7). In order to test fungicide effects on D. magna, parameters as survival, mean whole body length, mean total number of neonates per female, mean number of broods per female, mean brood size per female, time to first brood/reproduction and intrinsic rate of natural increase (r) were used. Reproduction was seriously affected by tebuconazole. All tebuconazole concentrations tested affected the number of broods per female and day to first brood. At 14-days test, number of neonates per female and body size decreased by concentrations of tebuconazole higher than 0.52mg/L, whereas at 21-days test both parameters were affected at all the concentrations tested. Survival of the daphnids after 14 days fungicide exposure did not exhibited differences among experimental and control groups. In this experiment r value was reduced (in a 22%) when animals were exposed to concentrations of 0.71mg/L and 1.14mg/L. Survival of daphnids exposed during 21 days to 1.14mg/L declined, and the intrinsic rate of natural increase (r) decreased in a 30 % for tebuconazole concentrations higher than 0.41mg/L. Longevity of daphnids pre-exposed to tebuconazole for 14 days and 7 days in clean water did not show differences from control values and all of them survived the 21 days of the test. However, after 7 days in fungicide free medium animals were unable to restore control values for reproductive parameters and length. The maximum acceptable toxicant concentration (MATC) was calculated using the r values as parameter of evaluation. MATC estimations were 0.61mg/L and 0.46mg/L for 14 and 21 days, respectively. Results showed that the number of neonates per female was the highest sensitive

  1. Smoking onset and the time-varying effects of self-efficacy, environmental smoking, and smoking-specific parenting by using discrete-time survival analysis

    NARCIS (Netherlands)

    Hiemstra, J.M.; Otten, R.; Engels, R.C.M.E.

    2012-01-01

    This study examined the timing of smoking onset during mid- or late adolescence and the time-varying effects of refusal self-efficacy, parental and sibling smoking behavior, smoking behavior of friends and best friend, and parental smoking-specific communication. We used data from five annual waves

  2. Effect of Migration Pathway on Travel Time and Survival of Acoustic-Tagged Juvenile Salmonids in the Columbia River Estuary

    Energy Technology Data Exchange (ETDEWEB)

    Harnish, Ryan A.; Johnson, Gary E.; McMichael, Geoffrey A.; Hughes, Michael S.; Ebberts, Blaine D.

    2012-02-01

    Off-channel areas (side channels, tidal flats, sand bars, and shallow-water bays) may serve as important migration corridors through estuarine environments for salmon and steelhead smolts. Relatively large percentages (21-33%) of acoustic-tagged yearling and subyearling Chinook salmon and steelhead smolts were detected migrating through off-channel areas of the Columbia River estuary in 2008. The probability of survival for off-channel migrants (0.78-0.94) was similar to or greater than the survival probability of main channel migrants (0.67-0.93). Median travel times were similar for all species or run types and migration pathways we examined, ranging from 1-2 d. The route used by smolts to migrate through the estuary may affect their vulnerability to predation. Acoustic-tagged steelhead that migrated nearest to avian predator nesting colonies experienced higher predation rates (24%) than those that migrated farthest from the colonies (10%). The use of multiple migration pathways may be advantageous to out-migrating smolts because it helps to buffer against high rates of mortality, which may occur in localized areas, and helps to minimize inter- and intraspecific competition.

  3. Time Management

    Science.gov (United States)

    Stoilov, Todor, Ed.

    2012-01-01

    The time management is worthy goal of many human activities. It concerns variety problems related to goals definition, assessment of available resources, control of management policies, scheduling of decisions. This book is an attempt to illustrate the decision making process in time management for different success stories, which can be used as…

  4. Spatializing Time

    DEFF Research Database (Denmark)

    Thomsen, Bodil Marie Stavning

    2011-01-01

    The article analyses some of artist Søren Lose's photographic installations in which time, history and narration is reflected in the creation of allegoric, spatial relations.......The article analyses some of artist Søren Lose's photographic installations in which time, history and narration is reflected in the creation of allegoric, spatial relations....

  5. About time

    CERN Document Server

    Frank, Adam

    2012-01-01

    From Stonehenge to beyond the Big Bang, an exhilarating scientific exploration of how we make time Time is the grandest conception of the universe that we humans have been able to imagine – and its most intimate, the very frame of human life. In About Time, astrophysicist and award-winning writer Adam Frank tells the scientific story of this wonderful and tyrannical invention. A Palaeolithic farmer moved through the sun-fuelled day and star-steered night in a radically different way than the Elizabethan merchants who set their pace to the clocks newly installed in their town squares. Since th

  6. Time out

    Science.gov (United States)

    ... to be quiet and think about their behavior. Time out is an effective disciplinary technique that does not use physical punishment. Professionals report that NOT physically punishing children may help ...

  7. The forecast of the postoperative survival time of patients suffered from non-small cell lung cancer based on PCA and extreme learning machine.

    Science.gov (United States)

    Han, Fei; Huang, De-Shuang; Zhu, Zhi-Hua; Rong, Tie-Hua

    2006-02-01

    In this paper, a new effective model is proposed to forecast how long the postoperative patients suffered from non-small cell lung cancer will survive. The new effective model which is based on the extreme learning machine (ELM) and principal component analysis (PCA) can forecast successfully the postoperative patients' survival time. The new model obtains better prediction accuracy and faster convergence rate which the model using backpropagation (BP) algorithm and the Levenberg-Marquardt (LM) algorithm to forecast the postoperative patients' survival time can not achieve. Finally, simulation results are given to verify the efficiency and effectiveness of our proposed new model.

  8. Is Leptospira able to survive in raw milk? Study on the inactivation at different storage times and temperatures.

    Science.gov (United States)

    Fratini, Filippo; Turchi, Barbara; Ferrone, Martina; Galiero, Alessia; Nuvoloni, Roberta; Torracca, Beatrice; Cerri, Domenico

    2016-09-01

    The consumption of raw milk is currently increasing due to several beneficial aspects, such as nutritional qualities, taste, and health benefits. However, some authors highlight the potential risk associated with raw milk consumption. In Italy, while the absence of some pathogen microorganisms is set by the regional regulation DGR 381/2007, for other microorganisms, such as Leptospira, no recommendations are provided. Leptospira is not ascribed among classical milk pathogens; however, it can potentially be present in raw milk. The aim of this study was to evaluate the survival in raw milk of six serovars of Leptospira after storage at different temperatures (4 °C ± 2 °C, 20 °C ± 2 °C, and 30 °C ± 2 °C) for different incubation times (20 min, 45 min, 1 h, and 1 h and 30 min), in order to determine the potential risk for consumers. Moreover, the immediate effect of bovine, goat, and donkey raw milk on tested Leptospira serovars was visually evaluated. After incubation, all samples were subcultured in EMJH and incubated aerobically at 30 °C for 3 months. All inoculated media were weekly examined by dark-field microscope in order to assess Leptospira survival. Extemporary observation of strains' behavior in milk allowed to detect an almost immediate motility loss, and no leptospires were detected by microscopic observations carried out weekly during the trial period. According to our results, it could be possible to exclude raw milk as a source of Leptospira infection for consumers.

  9. Brain Time and Physical Time

    Science.gov (United States)

    Fidelman, Uri

    The hemispheric paradigm verifies Kant's suggestion that time and space are our subjective modes of perceiving experience. Time and space are two modes of organizing the sensory input by the l- and right-hemispheric neural mechanisms, respectively. The neural structures of the l- and right-hemispheric mechanisms force our consciousness to perceive time as one-dimensional and propagating from the past towards the future, and space as a simultaneously perceived multidimensional structure. The introduction of temporal propagation from the future towards the past by Feynman and other physicists caused the transfer of the concept time from the l hemisphere (which cannot perceive this change of the temporal direction) to the right one. This transfer requires and allows for the introduction of additional temporal axes in order to solve paradoxes in physics.

  10. "Forget time"

    OpenAIRE

    Rovelli, Carlo

    2009-01-01

    Following a line of research that I have developed for several years, I argue that the best strategy for understanding quantum gravity is to build a picture of the physical world where the notion of time plays no role. I summarize here this point of view, explaining why I think that in a fundamental description of nature we must "forget time", and how this can be done in the classical and in the quantum theory. The idea is to develop a formalism that treats dependent and independent variables...

  11. Timing matters

    DEFF Research Database (Denmark)

    Kothari, Ninad B.; Wohlgemuth, Melville J.; Hulgard, Katrine

    2014-01-01

    To successfully negotiate a cluttered environment, an echolocating bat must control the timing of motor behaviors in response to dynamic sensory information. Here we detail the big brown bat's adaptive temporal control over sonar call production for tracking prey, moving predictably or unpredicta......To successfully negotiate a cluttered environment, an echolocating bat must control the timing of motor behaviors in response to dynamic sensory information. Here we detail the big brown bat's adaptive temporal control over sonar call production for tracking prey, moving predictably...

  12. Timing GMO

    DEFF Research Database (Denmark)

    Horsbøl, Anders; Lassen, Inger

    2011-01-01

     In this article we study the relationship of temporality and ideology through examples from a local controversy over field testing of genetically modified maize in a rural area in the north of Denmark. The primary focus of our study is on ways in which participants frame time on different...... timescales, ranging from representations of time in the present moment to representations of processes at shorter or longer timescales in the past or future. Looking at discourse from a temporal perspective opens up to simultaneous spatial scales where a global issue finds recontextualized meanings in local...

  13. Telling time

    Directory of Open Access Journals (Sweden)

    Populizio Ivan

    2002-06-01

    Full Text Available According to Einstein’s renowned declaration, for those who believe in physics – or, more precisely, in its capability to offer a “scientific” representation of the world – the distinction between present, past and future is just “an illusion, though obstinate”. If we consider an effective analogy by Mauro Dorato, we can state that those who agree with the famous German scientist will recognize in the present, past and future a relationship very similar to that between “here” and “somewhere else” – in other words, the present is just a located moment and has no privileged status. In other conceptual universes, some of which are explored by philosophy, or imagined by art, as well as in other scientific disciplines like biology, the need for a strong distinction between “what has happened”, “what will happen” and “what is happening” seems to be unavoidable. At the macroscopic level of living beings there does not seem to be a way out of the “eternal present”, which cannot be escaped even by the desire of some well-developed mammals to understand reality or such an apparently primary experience as the “passing of time”. Even the “timeless” description of reality offered by physics is immersed in time and changes with it. This paradox seems to contain the core of the irreducibility between two cultural constructions which we will be calling “the time of the soul” and “the time of the world”, after Ricoeur. The main thesis of this essay is that there are two fundamentally different ways of facing the mystery of time, which have a precise relationship with the mentioned contrast between the subjective and the objective conception of time – mental, qualitative and experienced in the first case; physical, quantitative and measurable in the second. Considering Ricoeur’s research on time and stories, we can conclude that this dichotomy may give rise to another similarly radical difference between

  14. Effects of cadmium and a one-time drought stress on survival, growth, and yield of native plant species

    Energy Technology Data Exchange (ETDEWEB)

    Miles, L.J.; Parker, G.R.

    1980-04-01

    Andropogon scoparius, Monarda fistulosa, and Rudbeckia hirta were grown from seed for 6 weeks in an uncontaminated rural site soil and a heavy metal-contaminated urban site soil. The rural site soil was amended with cadmium chloride. Plants grown in both soils were subjected to a one-time drought stress. Survival, shoot weight, root weight, total weight, height, and weekly growth of Andropogon and Monarda were adversely affected by cadmium (Cd) addition and drought stress. Results were similar for Rudbeckia except that shoot, root, and total weight were not significantly affected by drought stress. Root weights of Monarda and Andropogon were more severely affected by Cd addition than were shoot weights. Root-shoot ratios were not significantly affected by drought stress for any species. Drought stress and Cd addition effects were found to be additive for Monarda and Andropogon. The effect of soil Cd addition on growth was found to be primarily due to an initial delay in growth rather than a reduction in the overall rate of growth. However, on the heavy metal contamination urban site soil the growth rate was found to be reduced. This was especially true for Andropogon which was found to be most tolerant of Cd addition to the rural site soil for the species tested. The reduction in growth rate of plants on the urban site soil was probably not due to Cd alone.

  15. Comparison of survival time of Hawley and Vacuum-formed retainers in orthhodontic patients– a randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Seyed Hossein Moslemzadeh

    2017-01-01

    Full Text Available Background: Maintaining the results of orthodontic treatment and keeping the teeth in the corrected position is a great challenge in orthodontics. This study aimed to compare the survival time of three types of retainers including Hawley, 1-mm Vacuum-Formed (VF, and 1.5-mm VF within 6-month period. Methods: In this randomized clinical study, 152 patients were allocated into three groups to receive one type of the retainers. They were visited 1, 3, and 6 months after retainer delivery and checked for breakage, loss, local perforation, and discoloration from the patient's and clinician's point of view as indicators of failure. Chi-square and Fisher's exact tests were used as appropriated. Result: The results revealed that breakage was among the main reasons of failure of retainers within 6 months, which was statistically significantly different between Hawley and VF retainers, as well as between 1-mm and 1.5-mm VF retainers in the three intervals (p0.05. Assessing the discoloration from the patient's point of view revealed statistically significant differences between Hawley and VF retainers within the first month; however, the difference was not significant at the third and sixth months (p0.05. By the end of the sixth month, some of the VF retainers had perforation; while, perforation was not observed in Hawley retainers. Conclusion: Considering the higher breakage rate of 1-mm VF, 1.5-mm VF seems the retainer if choice.

  16. Transgenerational effects of parental nutritional status on offspring development time, survival, fecundity, and sensitivity to zinc in Chironomus tepperi midges.

    Science.gov (United States)

    Colombo, Valentina; Pettigrove, Vincent J; Golding, Lisa A; Hoffmann, Ary A

    2014-12-01

    Environmental stimuli can induce plastic changes in life history traits, and stimuli experienced by parents can be transmitted to the next generation ("transgenerational") through the inheritance of factors unrelated to changes in DNA sequences. Transgenerational effects are common in species living in habitats subjected to recurrent stressful events, such as fluctuating resource availability. In a previous study, the nutritional status of the midge Chironomus tepperi has been reported to influence life history traits of the offspring. In this study we investigated whether they also alter sensitivity of offspring to zinc. Offspring of parents reared under low food conditions had a shorter development time and lower reproductive output compared to offspring of parents raised under excess food. While zinc exposure decreased the survival of offspring generally, the interaction between parental food level and zinc exposure did not influence the relative sensitivity of offspring toward zinc. Parental nutritional stress therefore triggered transgenerational effects, potentially acting as confounding factors in ecotoxicological studies, but they did not directly affect the susceptibility of offspring to zinc. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Mental health selection and income support dynamics: multiple spell discrete-time survival analyses of welfare receipt.

    Science.gov (United States)

    Kiely, Kim M; Butterworth, Peter

    2014-04-01

    The higher occurrence of common psychiatric disorders among welfare recipients has been attributed to health selection, social causation and underlying vulnerability. The aims of this study were to test for the selection effects of mental health problems on entry and re-entry to working-age welfare payments in respect to single parenthood, unemployment and disability. Nationally representative longitudinal data were drawn from the Household Income and Labour Dynamics in Australia survey. Multiple spell discrete-time survival analyses were conducted using multinomial logistic regression models to test if pre-existing mental health problems predicted transitions to welfare. Analyses were stratified by sex and multivariate adjusted for mental health problems, father's occupation, socioeconomic position, marital status, employment history, smoking status and alcohol consumption, physical function and financial hardship. All covariates were modelled as either lagged effects or when a respondent was first observed to be at risk of income support. Mental health problems were associated with increased risk of entry and re-entry to disability, unemployment and single parenting payments for women, and disability and unemployment payments for men. These associations were attenuated but remained significant after adjusting for contemporaneous risk factors. Although we do not control for reciprocal causation, our findings are consistent with a health selection hypothesis and indicate that mental illness may be a contributing factor to later receipt of different types of welfare payments. We argue that mental health warrants consideration in the design and targeting of social and economic policies.

  18. Evaluation of clinical and histologic factors associated with survival time in dogs with stage II splenic hemangiosarcoma treated by splenectomy and adjuvant chemotherapy: 30 cases (2011-2014).

    Science.gov (United States)

    Moore, Antony S; Rassnick, Kenneth M; Frimberger, Angela E

    2017-09-01

    OBJECTIVE To determine histologic and clinical factors associated with survival time in dogs with stage II splenic hemangiosarcoma treated by splenectomy and a chemotherapy protocol in which an anthracycline was alternated with lomustine. DESIGN Retrospective case series. ANIMALS 30 dogs with stage II splenic hemangiosarcoma. PROCEDURES Medical records of 3 facilities were reviewed to identify dogs treated for stage II splenic hemangiosarcoma between June 2011 and October 2014. Information collected included signalment, disease staging data, whether anemia was present, date of splenectomy, chemotherapy protocol, adverse effects, and date of death or last follow-up. Histologic slides were reviewed and scored by pathologists. Associations between variables of interest and survival data were evaluated statistically. RESULTS Median survival time for all dogs was 158 days (range, 55 to 560 days), and the 1-year survival rate was 16%. On multivariate analysis, only the histologically determined mitotic score was significantly associated with survival time. The median survival time of 292 days for dogs with a mitotic score of 0 (hemangiosarcoma.

  19. The impact of pamidronate and chemotherapy on survival times in dogs with appendicular primary bone tumors treated with palliative radiation therapy.

    Science.gov (United States)

    Oblak, Michelle L; Boston, Sarah E; Higginson, Geraldine; Patten, Steven G; Monteith, Gabrielle J; Woods, J Paul

    2012-04-01

    To assess survival times in dogs that received palliative radiation therapy (RT) alone, and in combination with chemotherapy, pamidronate, or both for primary appendicular bone tumors and determine whether the addition of these adjunctive therapies affects survival. Retrospective case series. Dogs (n = 50) with primary appendicular bone tumors. Dogs were divided into the following treatment groups: RT alone, RT + chemotherapy, RT+ pamidronate, and RT+ chemotherapy + pamidronate. Dogs were considered for analysis if they had a known euthanasia date or follow-up data were available for at least 120 days from the time of diagnosis. Survival time was defined as the time from admission to euthanasia. Cox proportional hazard models and Kaplan-Meier survival functions were used. A P value of less than .05 was considered significant. Fifty dogs were considered for survival analysis. Median survival times (MSTs) were longest for dogs receiving RT and chemotherapy (307 days; 95% CI: 279, 831) and shortest in dogs receiving RT and pamidronate (69 days; 95% CI: 47, 112 days). The difference in MST between dogs who received pamidronate and those who did not in this population was statistically significant in a univariate (P = .039) and multivariate analysis (P = .0015). The addition of chemotherapy into any protocol improved survival (P Chemotherapy should be recommended in addition to a palliative RT protocol to improve survival of dogs with primary appendicular bone tumors. When combined with RT ± chemotherapy, pamidronate decreased MST and should not be included in a standard protocol. © Copyright 2012 by The American College of Veterinary Surgeons.

  20. A comparison of the conditional inference survival forest model to random survival forests based on a simulation study as well as on two applications with time-to-event data.

    Science.gov (United States)

    Nasejje, Justine B; Mwambi, Henry; Dheda, Keertan; Lesosky, Maia

    2017-07-28

    Random survival forest (RSF) models have been identified as alternative methods to the Cox proportional hazards model in analysing time-to-event data. These methods, however, have been criticised for the bias that results from favouring covariates with many split-points and hence conditional inference forests for time-to-event data have been suggested. Conditional inference forests (CIF) are known to correct the bias in RSF models by separating the procedure for the best covariate to split on from that of the best split point search for the selected covariate. In this study, we compare the random survival forest model to the conditional inference model (CIF) using twenty-two simulated time-to-event datasets. We also analysed two real time-to-event datasets. The first dataset is based on the survival of children under-five years of age in Uganda and it consists of categorical covariates with most of them having more than two levels (many split-points). The second dataset is based on the survival of patients with extremely drug resistant tuberculosis (XDR TB) which consists of mainly categorical covariates with two levels (few split-points). The study findings indicate that the conditional inference forest model is superior to random survival forest models in analysing time-to-event data that consists of covariates with many split-points based on the values of the bootstrap cross-validated estimates for integrated Brier scores. However, conditional inference forests perform comparably similar to random survival forests models in analysing time-to-event data consisting of covariates with fewer split-points. Although survival forests are promising methods in analysing time-to-event data, it is important to identify the best forest model for analysis based on the nature of covariates of the dataset in question.

  1. Epithelial ovarian cancer mortality among Hispanic women: Sub-ethnic disparities and survival trend across time: An analysis of SEER 1992-2013.

    Science.gov (United States)

    Chen, Chen; Markossian, Talar W; Silva, Abigail; Tarasenko, Yelena N

    2018-02-01

    Over the past half century the proportion of Hispanics in the US population has been steadily increasing, and groups of Hispanic origin have diversified. Despite notable racial and ethnic disparities in ovarian cancer (OC) mortality, population-based studies on OC among Hispanic females are lacking. To examine sub-ethnic disparities in OC mortality and survival trends using the Surveillance, Epidemiology, and End Results Program (SEER) 18 data on Hispanic women diagnosed with epithelial OC during 1992-2013. The disparities in OC 5 year survival and mortality were examined using log-rank tests and Cox proportional hazards models, adjusted for sociodemographic and pathological characteristics, time of diagnosis, receipt of resection surgery and county socioeconomic status. Trends in 5-year survival rates were examined using joinpoint regression models. The 5-year survival was lowest in Puerto Ricans (median survival: 33 months; survival rate: 31.07%) and was highest in the "Other" Hispanic subgroup (median survival: 59 months; survival rate: 49.14%) (log-rank test: P survival rates: from 43.37% to 48.94% (APC = 0.41, P = 0.40) and from 48.72% to 53.46% (APC = 0.29, P = 0.50), respectively. OC mortality in Hispanic patients varied by sub-ethnicity. This heterogeneity should be considered in future cancer data collection, reports and research. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Conditional Survival: An Assessment of the Prognosis of Patients at Time Points After Initial Diagnosis and Treatment of Locoregional Melanoma Metastasis.

    Science.gov (United States)

    Haydu, Lauren E; Scolyer, Richard A; Lo, Serigne; Quinn, Michael J; Saw, Robyn P M; Shannon, Kerwin F; Spillane, Andrew J; Stretch, Jonathan R; McCarthy, William H; Thompson, John F

    2017-05-20

    Purpose Standard cancer staging and prognostic estimates are determined at the time of the patient's initial disease presentation. Conditional survival is an alternative, dynamic assessment from follow-up time points after the initial disease diagnosis and is based on the condition of survivorship. Estimates of conditional survival can provide critical prognostic information for patients and clinicians, guide subsequent cancer follow-up schedules, and influence decisions regarding treatments. The current study presents conditional survival estimates developed from a cohort of 4,540 patients diagnosed with stage III melanoma treated at a single institution. Methods Patients with stage III disease at first melanoma diagnosis (initial; n = 2,042), or who developed locoregional metastasis as a first recurrence some time after primary diagnosis (recurrent; n = 2,498), were assessed. Conditional melanoma-specific survival (MSS) estimates up to 5 years after diagnosis were adjusted for age, sex, and 8th edition American Joint Committee on Cancer (AJCC) stage. Results Older age at diagnosis of stage III disease conveyed a worse prognosis at each conditional survival time point. Males had significantly worse MSS outcomes for up to 2 years of conditional survival, after which males and females had similar MSS. For patients with AJCC stage IIIB and stage IIIC disease, MSS outcomes were similar to those of patients with stage IIIA disease after 3 and 5 years of survivorship, respectively. Conclusion Adjuvant systemic treatments may have the greatest benefit when administered within the first 2 years of stage III melanoma diagnosis, during which period prognosis is significantly worse for male patients of increasing age and AJCC substage. Conditional survival estimates illustrate improved survival prospects for patients with cancer returning for follow-up and may define a finite period of increased risk after diagnosis.

  3. Alcohol use at time of injury and survival following traumatic brain injury: results from the National Trauma Data Bank.

    Science.gov (United States)

    Chen, Chiung M; Yi, Hsiao-Ye; Yoon, Young-Hee; Dong, Chuanhui

    2012-07-01

    Premised on biological evidence from animal research, recent clinical studies have, for the most part, concluded that elevated blood alcohol concentration levels are independently associated with higher survival or decreased mortality in patients with moderate to severe traumatic brain injury (TBI). This study aims to provide some counterevidence to this claim and to further future investigations. Incident data were drawn from the largest U.S. trauma registry, the National Trauma Data Bank, for emergency department admission years 2002-2006. TBI was identified according to the National Trauma Data Bank's definition using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM), codes. To eliminate confounding, the exact matching method was used to match alcohol-positive with alcohol-negative incidents on sex, age, race/ethnicity, and facility. Logistic regression compared in-hospital mortality between 44,043 alcohol-positive and 59,817 matched alcohol-negative TBI incidents, with and without causes and intents of TBI and Injury Severity Score as covariates. A sensitivity analysis was performed within a subsample of isolated moderate to severe TBI incidents. Alcohol use at the time of injury was found to be significantly associated with an increased risk for TBI. Including varied causes and intents of TBI and Injury Severity Score as potential confounders in the regression model explained away the statistical significance of the seemingly protective effect of alcohol against TBI mortality for all TBIs and for isolated moderate to severe TBIs. The null finding shows that the purported reduction in TBI mortality attributed to positive blood alcohol likely is attributable to residual confounding. Accordingly, the risk of TBI associated with alcohol use should not be overlooked.

  4. Timing earnings

    Directory of Open Access Journals (Sweden)

    Donghua Chen

    2011-12-01

    Full Text Available Since the opening of China’s securities market, there have been a number of bull and bear cycles. This paper discusses how executives use the market timing approach to manage earnings in different cycles to maximize firm value. We find that Chinese listed companies choose to release more earnings during bull markets and this phenomenon is more evident in companies that are more profitable and have higher valuations. We also find that executives who do not release more earnings during bull markets are more likely to be dismissed.

  5. Heterogeneic Time

    DEFF Research Database (Denmark)

    Simonsen, Karen-Margrethe

    2018-01-01

    The focus of this article is the relation between time and transcultural space in literary history. The argument is that the concept of anachronism can help us understand the complexity of temporality and that the analysis of transcultural exchanges between European and Latin American art...... and literature may change literary history and further an understanding of the anachronism of Eurochronology. Two examples of a transcultural and anachronistic relation between Europe and America will be analysed, both of them novels and writers of magical realism. Gabriel García Márquez’s novel Cien años de...

  6. The relationship between annual survival rate and migration distance in mallards: an examination of the time-allocation hypothesis for the evolution of migration

    Science.gov (United States)

    Hestbeck, J.B.; Nichols, J.D.; Hines, J.E.

    1992-01-01

    Predictions of the time-allocation hypothesis were tested with several a posteriori analyses of banding data for the mallard (Anas platyrhynchos). The time-allocation hypothesis states that the critical difference between resident and migrant birds is their allocation of time to reproduction on the breeding grounds and survival on the nonbreeding grounds. Residents have higher reproduction and migrants have higher survival. Survival and recovery rates were estimated by standard band-recovery methods for banding reference areas in the central United States and central Canada. A production-rate index was computed for each reference area with data from the U.S. Fish and Wildlife Service May Breeding Population Survey and July Production Survey. An analysis of covariance was used to test for the effects of migration distance and time period (decade) on survival, recovery, and production rates. Differences in migration chronology were tested by comparing direct-recovery distributions for different populations during the fall migration. Differences in winter locations were tested by comparing distributions of direct recoveries reported during December and January. A strong positive relationship was found between survival rate, and migration distance for 3 of the 4 age and sex classes. A weak negative relationship was found between recovery rate and migration distance. No relationship was found between production rate and migration distance. During the fall migration, birds from the northern breeding populations were located north of birds from the southern breeding populations. No pattern could be found in the relative locations of breeding and wintering areas. Although our finding that survival rate increased with migration distance was consistent with the time-allocation hypothesis, our results on migration chronology and location of wintering areas were not consistent with the mechanism underlying the time-allocation hypothesis. Neither this analysis nor other recent

  7. time horizon

    Directory of Open Access Journals (Sweden)

    Thordur Runolfsson

    2000-01-01

    Full Text Available A risk-sensitive optimal control problem is considered for a hybrid system that consists of continuous time diffusion process that depends on a discrete valued mode variable that is modeled as a Markov chain. Optimality conditions are presented and conditions for the existence of optimal controls are derived. It is shown that the optimal risk-sensitive control problem is equivalent to the upper value of an associated stochastic differential game, and insight into the contributions of the noise input and mode variable to the risk sensitivity of the cost functional is given. Furthermore, it is shown that due to the mode variable risk sensitivity, the equivalence relationship that has been observed between risk-sensitive and H∞ control in the nonhybrid case does not hold for stochastic hybrid systems.

  8. Time matters

    DEFF Research Database (Denmark)

    Andreasen, Karen Egedal; Rasmussen, Annette

    such as the PISA studies, and tendencies in educational politics and schoolsystems in Europe, USA, Australia and Asia. This spring (2011) all danish pupils in grade 6. has been tested nationally for the first time in reading skills and mathematics. The argumentation behind the initiative points to both economical......During 2011 national standardised testing within areas such as reading, mathematics, science etc. has been introduced in Danish compulsory school by the Educational Ministry as something new. The inspirations behind this initiative are both the international comparative educational studies...... advantages and to, that testing is meant to support pupils development of academical skills at school. Though the important question is which effects that will in fact be the consequences from this initiative. As a part of a research project supported by The Danish Research Council, initiated spring 2010 I...

  9. Cloud time

    CERN Document Server

    Lockwood, Dean

    2012-01-01

    The ‘Cloud’, hailed as a new digital commons, a utopia of collaborative expression and constant connection, actually constitutes a strategy of vitalist post-hegemonic power, which moves to dominate immanently and intensively, organizing our affective political involvements, instituting new modes of enclosure, and, crucially, colonizing the future through a new temporality of control. The virtual is often claimed as a realm of invention through which capitalism might be cracked, but it is precisely here that power now thrives. Cloud time, in service of security and profit, assumes all is knowable. We bear witness to the collapse of both past and future virtuals into a present dedicated to the exploitation of the spectres of both.

  10. Single nucleotide polymorphisms in the D-loop region of mitochondrial DNA is associated with the kidney survival time in chronic kidney disease patients.

    Science.gov (United States)

    Xu, Jinsheng; Guo, Zhanjun; Bai, Yaling; Zhang, Junxia; Cui, Liwen; Zhang, Huiran; Zhang, Shenglei; Ai, Xiaolu

    2015-02-01

    The mitochondrial displacement loop (D-loop) is known to accumulate mutations and SNPs at a higher frequency than other regions of mitochondrial DNA (mtDNA). We had identified chronic kidney disease (CKD) risk-associated SNPs in the D-loop of CKD patients previously. In this study, we investigated the association of SNPs in the D-loop of mtDNA with the kidney survival of CKD. The D-loop region of mtDNA was sequenced for 119 CKD patients from the inpatient of the Fourth Hospital of Hebei Medical University. The Kaplan-Meier method was used to identify disease outcome-associated SNPs in the D-loop of CKD patients. The Cox proportional hazards model was used to identify risk factors for the kidney survival of CKD. In the present study, we identified 20 SNPs with a frequency higher than 5% and assessed the relationship of these SNPs with kidney survival time in CKD patients, a SNP of 146 was identified by log-rank test for statistically significant prediction of the kidney survival time. In an overall multivariate analysis, allele 146 was identified as an independent predictor of kidney survival time in CKD patients. The survival time of kidney in the CKD patients with 146C was significantly shorter than that of kidney in CKD patients with 146T (relative risk, 2.336; 95% CI, 1.319-3.923; p = 0.001). SNPs in the D-loop can predict the kidney survival of CKD patients. Analysis of genetic polymorphisms in the mitochondrial D-loop can help to identify CKD patient subgroup at high risk of a poor disease outcome.

  11. The influence of a covariate on optimal designs in longitudinal studies with discrete-time survival endpoints

    NARCIS (Netherlands)

    Safarkhani, Maryam; Moerbeek, Mirjam

    Longitudinal intervention studies on event occurrence can measure the timing of an event at discrete points in time. To design studies of this kind as inexpensively and efficiently as possible, researchers need to decide on the number of subjects and the number of measurements for each subject.

  12. Time-varying effects of aromatic oil constituents on the survival of aquatic species: Deviations between model estimates and observations

    NARCIS (Netherlands)

    Hoop, L. de; Viaene, K.P.; Schipper, A.M.; Huijbregts, M.A.; De Laender, F.; Hendriks, A.J.

    2017-01-01

    There is a need to study the time course of toxic chemical effects on organisms because there might be a time lag between the onset of chemical exposure and the corresponding adverse effects. For aquatic organisms, crude oil and oil constituents originating from either natural seeps or human

  13. Consequences of cold-ischemia time on primary nonfunction and patient and graft survival in liver transplantation: a meta-analysis.

    Directory of Open Access Journals (Sweden)

    James E Stahl

    2008-06-01

    Full Text Available The ability to preserve organs prior to transplant is essential to the organ allocation process.The purpose of this study is to describe the functional relationship between cold-ischemia time (CIT and primary nonfunction (PNF, patient and graft survival in liver transplant.To identify relevant articles Medline, EMBASE and the Cochrane database, including the non-English literature identified in these databases, was searched from 1966 to April 2008. Two independent reviewers screened and extracted the data. CIT was analyzed both as a continuous variable and stratified by clinically relevant intervals. Nondichotomous variables were weighted by sample size. Percent variables were weighted by the inverse of the binomial variance.Twenty-six studies met criteria. Functionally, PNF% = -6.678281+0.9134701*CIT Mean+0.1250879*(CIT Mean-9.895352-0.0067663*(CIT Mean-9.895353, r2 = .625, , p<.0001. Mean patient survival: 93% (1 month, 88% (3 months, 83% (6 months and 83% (12 months. Mean graft survival: 85.9% (1 month, 80.5% (3 months, 78.1% (6 months and 76.8% (12 months. Maximum patient and graft survival occurred with CITs between 7.5-12.5 hrs at each survival interval. PNF was also significantly correlated with ICU time, % first time grafts and % immunologic mismatches.The results of this work imply that CIT may be the most important pre-transplant information needed in the decision to accept an organ.

  14. Effect of time interval between capecitabine intake and radiotherapy on local recurrence-free survival in preoperative chemoradiation for locally advanced rectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yeon Joo; Kim, Jong Hoon; Yu, Chang Sik; Kim, Tae Won; Jang, Se Jin; Choi, Eun Kyung; Kim, Jin Cheon [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Choi, Won Sik [University of Ulsan College of Medicine, Gangneung (Korea, Republic of)

    2017-06-15

    The concentration of capecitabine peaks at 1–2 hours after administration. We therefore assumed that proper timing of capecitabine administration and radiotherapy would maximize radiosensitization and influence survival among patients with locally advanced rectal cancer. We retrospectively reviewed 223 patients with locally advanced rectal cancer who underwent preoperative chemoradiation, followed by surgery from January 2002 to May 2006. All patients underwent pelvic radiotherapy (50 Gy/25 fractions) and received capecitabine twice daily at 12-hour intervals (1,650 mg/m2/day). Patients were divided into two groups according to the time interval between capecitabine intake and radiotherapy. Patients who took capecitabine 1 hour before radiotherapy were classified as Group A (n = 109); all others were classified as Group B (n = 114). The median follow-up period was 72 months (range, 7 to 149 months). Although Group A had a significantly higher rate of good responses (44% vs. 25%; p = 0.005), the 5-year local recurrence-free survival rates of 93% in Group A and 97% in Group B did not differ significantly (p = 0.519). The 5-year disease-free survival and overall survival rates were also comparable between the groups. Despite the better pathological response in Group A, the time interval between capecitabine and radiotherapy administration did not have a significant effect on survivals. Further evaluations are needed to clarify the interaction of these treatment modalities.

  15. Jointly modeling longitudinal proportional data and survival times with an application to the quality of life data in a breast cancer trial.

    Science.gov (United States)

    Song, Hui; Peng, Yingwei; Tu, Dongsheng

    2017-04-01

    Motivated by the joint analysis of longitudinal quality of life data and recurrence free survival times from a cancer clinical trial, we present in this paper two approaches to jointly model the longitudinal proportional measurements, which are confined in a finite interval, and survival data. Both approaches assume a proportional hazards model for the survival times. For the longitudinal component, the first approach applies the classical linear mixed model to logit transformed responses, while the second approach directly models the responses using a simplex distribution. A semiparametric method based on a penalized joint likelihood generated by the Laplace approximation is derived to fit the joint model defined by the second approach. The proposed procedures are evaluated in a simulation study and applied to the analysis of breast cancer data motivated this research.

  16. The association between timing of initiation of adjuvant therapy and the survival of early stage ovarian cancer patients - An analysis of NRG Oncology/Gynecologic Oncology Group trials.

    Science.gov (United States)

    Chan, John K; Java, James J; Fuh, Katherine; Monk, Bradley J; Kapp, Daniel S; Herzog, Thomas; Bell, Jeffrey; Young, Robert

    2016-12-01

    To determine the association between timing of adjuvant therapy initiation and survival of early stage ovarian cancer patients. Data were obtained from women who underwent primary surgical staging followed by adjuvant therapy from two Gynecologic Oncology Group trials (protocols # 95 and 157). Kaplan-Meier estimates and Cox proportional hazards model adjusted for covariates were used for analyses. Of 497 stage I-II epithelial ovarian cancer patients, the median time between surgery and initiation of adjuvant therapy was 23days (25th-75th%: 12-33days). The time interval from surgery to initiation of adjuvant therapy was categorized into three groups: 4weeks. The corresponding 5-year recurrence-free survival rates were 72.8%, 73.9%, and 79.5% (p=0.62). The 5-year overall survival rates were 79.4%, 81.9%, and 82.8%, respectively (p=0.51; p=0.33 - global test). As compared to 4weeks. Age, stage, grade, and cytology were important prognostic factors. Timing of adjuvant therapy initiation was not associated with survival in early stage epithelial ovarian cancer patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Blockade of CD40-CD154 at the time of donor-specific blood transfusion does not lead to prolonged kidney allograft survival in nonhuman primates

    NARCIS (Netherlands)

    Ringers, J; Haanstra, KG; Kroczek, RA; Kliem, K; Kuhn, EM; Wubben, J; Ossevoort, MA; Volk, HD; Jonker, M

    2002-01-01

    Background. In rodents it has been demonstrated that blockade of the CD40-CD154 (CD40L) pathway at the time of donor-specific blood transfusion (DST) can result in indefinite graft survival. Because it has been reported in the past that DST in monkeys can have a favorable effect on graft outcome and

  18. Risk of Early Onset Substance Use among Students with and without Mild Academic Disabilities: Results of a Discrete-Time Survival Analysis

    Science.gov (United States)

    Kepper, Annelies; Koning, Ina; Vollebergh, Wilma; Monshouwer, Karin

    2014-01-01

    This study investigated the age of onset of substance use among 536 students with mild academic disabilities and 906 students without academic disabilities, and the extent to which emotional, conduct, and hyperactivity problems explain the differences between these two groups. Using discrete-time survival analysis, the results of this study showed…

  19. Yet another time about time

    CERN Document Server

    Simeonov, Plamen L

    2015-01-01

    This paper presents yet another personal reflection on one the most important concepts in both science and the humanities: time. This elusive notion has been not only bothering philosophers since Plato and Aristotle and goes throughout human history embracing all analytical and creative (anthropocentric) disciplines from mathematics through physical and life sciences to philosophy, psychology, music and art, with a vast body of knowledge across different theories and categories concerning its nature (rational, irrational, arational), appearances/qualia, degrees, dimensions and scales of conceptualization (internal, external, rational, irrational, fractal, discrete, continuous, mechanical, quantum, local, global, etc.), duration ranges, resolutions, modes (present, now, past, future), variety of tenses (e.g. present perfect, present progressive, etc.) and some intuitive, but also fancy phenomenological characteristics such as arrow, stream, texture, width, depth, and perhaps the most distinct one of them, the ...

  20. The effects of ambient temperature and mixing time of glass ionomer cement material on the survival rate of proximal ART restorations in primary molars

    Directory of Open Access Journals (Sweden)

    Arthur M Kemoli

    2014-01-01

    Full Text Available Objective: Temperature fluctuations and material mixing times are likely to affect the consistency and integrity of the material mixture, and hence the restoration made out of it. The purpose of the present study was to determine the influence of the ambient temperature and the mixing time of glass ionomer cement (GIC restorative material on the survival rate of proximal atraumatic restorative treatment (ART restorations placed in primary molars. Materials and Methods: A total of 804 restorations were placed in the primary molars of 6-8-year-olds using the ART approach. The restorations were then followed for a period of 2 years and evaluated at given intervals. The data collected were analyzed using SPSS computer statistical program, and the results tested and compared using the Chi-square, Kaplan Meier survival analysis and Cox Proportional hazard statistical tests. Results: The cumulative survival rate of the restorations dropped from the initial 94.4% to 30.8% at the end of 2 years. The higher survival rate of the restorations was associated with the experienced operators and assistants when using the rubber dam isolation method. However, there was no statistically significant difference in the survival rate of the restorations when related to the room temperature and the mixing time of the GIC materials used in spite of the variations in the temperature recoded and the methods used in mixing the materials. Conclusion: The ambient temperature and mixing time of GIC did not have a significant effect on the survival of the proximal ART restorations.

  1. Process algebra with timing: Real time and discrete time

    NARCIS (Netherlands)

    Baeten, J.C.M.; Middelburg, C.A.

    1999-01-01

    We present real time and discrete time versions of ACP with absolute timing and relative timing. The startingpoint is a new real time version with absolute timing, called ACPsat , featuring urgent actions and a delay operator. The discrete time versions are conservative extensions of the discrete

  2. Impact of marital status at diagnosis on survival and its change over time between 1973 and 2012 in patients with nasopharyngeal carcinoma: a propensity score-matched analysis.

    Science.gov (United States)

    Xu, Cheng; Liu, Xu; Chen, Yu-Pei; Mao, Yan-Ping; Guo, Rui; Zhou, Guan-Qun; Tang, Ling-Long; Lin, Ai-Hua; Sun, Ying; Ma, Jun

    2017-12-01

    The impact of marital status at diagnosis on survival outcomes and its change over time in patients with nasopharyngeal carcinoma (NPC) are unclear. The Surveillance, Epidemiology, and End Results (SEER) database was used to identify patients diagnosed with NPC in the United States from 1973 to 2012. A primary comparison (married vs. unmarried) was implemented with 1:1 propensity score matching. Secondary comparisons were performed individually between three unmarried subgroups (single, separated/divorced, widowed) and married group. The effect of marital status on cause-specific survival (CSS) and overall survival (OS) were evaluated using univariate/multivariate analysis. Moreover, we investigated the change over time (1973-2012) in the effect of marital status on NPC survival. Married patients had better 5-year CSS/OS than unmarried patients (61.1% vs. 52.6%, P < 0.001; 55.6% vs. 45.3%, P < 0.001, respectively). In multivariate analysis, unmarried patients had significantly poorer CSS/OS than married patients (adjusted hazard ratio [aHR] = 1.35, P < 0.001; aHR = 1.40, P < 0.001, respectively). The survival benefit of being married was only detected in non-Hispanic white and Chinese American patients. Single, separated/divorced, and widowed patients had significantly poorer CSS/OS than married patients (aHR = 1.37 and 1.37; 1.46 and 1.42; 1.43 and 1.48, respectively; all P < 0.001). The change over time in the effect of marital status on survival was more stable in male than female. The strength of the negative effect of separated/divorced and widowed status showed a downward and upward trend, respectively. Gender difference in the adverse effect of single status on NPC survival became smaller over time. Only non-Hispanic white and Chinese American patients with NPC obtain survival benefits from married status. Single and widowed patients are regarded as high-risk population. © 2017 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  3. Retrospective epidemiological study of canine epilepsy in Japan using the International Veterinary Epilepsy Task Force classification 2015 (2003-2013): etiological distribution, risk factors, survival time, and lifespan.

    Science.gov (United States)

    Hamamoto, Yuji; Hasegawa, Daisuke; Mizoguchi, Shunta; Yu, Yoshihiko; Wada, Masae; Kuwabara, Takayuki; Fujiwara-Igarashi, Aki; Fujita, Michio

    2016-11-09

    Epilepsy is the most common neurological disease in veterinary practice. However, contrary to human medicine, epilepsy classification in veterinary medicine had not been clearly defined until recently. A number of reports on canine epilepsy have been published, reflecting in part updated proposals from the human epilepsy organization, the International League Against Epilepsy. In 2015, the International Veterinary Epilepsy Task Force (IVETF) published a consensus report on the classification and definition of canine epilepsy. The purpose of this retrospective study was to investigate the etiological distribution, survival time of dogs with idiopathic epilepsy (IdE) and structural epilepsy (StE), and risk factors for survival time, according to the recently published IVETF classification. We investigated canine cases with epilepsy that were referred to our teaching hospital in Japan during the past 10 years, and which encompassed a different breed population from Western countries. A total of 358 dogs with epilepsy satisfied our etiological study criteria. Of these, 172 dogs (48 %) were classified as IdE and 76 dogs (21 %) as StE. Of these dogs, 100 dogs (consisting of 65 with IdE and 35 with StE) were included in our survival study. Median survival time from the initial epileptic seizure in dogs with IdE and StE was 10.4 and 4.5 years, respectively. Median lifespan of dogs with IdE and StE was 13.5 and 10.9 years, respectively. Multivariable analysis demonstrated that risk factors for survival time in IdE were high seizure frequency (≥0.3 seizures/month) and focal epileptic seizures. Focal epileptic seizures were identified as a risk factor for survival time in IdE. Clinicians should carefully differentiate seizure type as it is difficult to identify focal epileptic seizures. With good seizure control, dogs with IdE can survive for nearly the same lifespan as the general dog population. Our results using the IVETF classification are similar to previous

  4. Gray’s Time-Varying Coefficients Model for Posttransplant Survival of Pediatric Liver Transplant Recipients with a Diagnosis of Cancer

    Directory of Open Access Journals (Sweden)

    Yi Ren

    2013-01-01

    Full Text Available Transplantation is often the only viable treatment for pediatric patients with end-stage liver disease. Making well-informed decisions on when to proceed with transplantation requires accurate predictors of transplant survival. The standard Cox proportional hazards (PH model assumes that covariate effects are time-invariant on right-censored failure time; however, this assumption may not always hold. Gray’s piecewise constant time-varying coefficients (PC-TVC model offers greater flexibility to capture the temporal changes of covariate effects without losing the mathematical simplicity of Cox PH model. In the present work, we examined the Cox PH and Gray PC-TVC models on the posttransplant survival analysis of 288 pediatric liver transplant patients diagnosed with cancer. We obtained potential predictors through univariable (P<0.15 and multivariable models with forward selection (P<0.05 for the Cox PH and Gray PC-TVC models, which coincide. While the Cox PH model provided reasonable average results in estimating covariate effects on posttransplant survival, the Gray model using piecewise constant penalized splines showed more details of how those effects change over time.

  5. Survival of timber rattlesnakes (Crotalus horridus) estimated by capture-recapture models in relation to age, sex, color morph, time, and birthplace

    Science.gov (United States)

    Brown, W.S.; Kery, M.; Hines, J.E.

    2007-01-01

    Juvenile survival is one of the least known elements of the life history of many species, in particular snakes. We conducted a mark–recapture study of Crotalus horridus from 1978–2002 in northeastern New York near the northern limits of the species' range. We marked 588 neonates and estimated annual age-, sex-, and morph-specific recapture and survival rates using the Cormack-Jolly-Seber (CJS) model. Wild-caught neonates (field-born, n  =  407) and neonates produced by captive-held gravid females (lab-born, n  =  181) allowed comparison of the birthplace, or lab treatment effect, in estimated survival. Recapture rates declined from about 10–20% over time while increasing from young to older age classes. Estimated survival rates (S ± 1 SE) in the first year were significantly higher among field-born (black morph: S  =  0.773 ± 0.203; yellow morph: S  =  0.531 ± 0.104) than among lab-born snakes (black morph: S  =  0.411 ± 0.131; yellow morph: S  =  0.301 ± 0.081). Lower birth weights combined with a lack of field exposure until release apparently contributed to the lower survival rate of lab-born snakes. Subsequent survival estimates for 2–4-yr-old snakes were S  =  0.845 ± 0.084 for the black morph and S  =  0.999 (SE not available) for the yellow morph, and for ≥5-yr-old snakes S  =  0.958 ± 0.039 (black morph) and S  =  0.822 ± 0.034 (yellow morph). The most parsimonious model overall contained an independent time trend for survival of each age, morph, and lab-treatment group. For snakes of the first two age groups (ages 1 yr and 2–4 yr), survival tended to decline over the years for both morphs, while for adult snakes (5 yr and older), survival was constant or even slightly increased. Our data on survival and recapture are among the first rigorous estimates of these parameters in a rattlesnake and among the few yet available for any viperid snake. These data are useful for analyses of the life

  6. Complex karyotype in mantle cell lymphoma is a strong prognostic factor for the time to treatment and overall survival, independent of the MCL international prognostic index.

    Science.gov (United States)

    Sarkozy, Clémentine; Terré, Christine; Jardin, Fabrice; Radford, Isabelle; Roche-Lestienne, Catherine; Penther, Dominique; Bastard, Christian; Rigaudeau, Sophie; Pilorge, Sylvain; Morschhauser, Franck; Bouscary, Didier; Delarue, Richard; Farhat, Hassan; Rousselot, Philippe; Hermine, Olivier; Tilly, Hervé; Chevret, Sylvie; Castaigne, Sylvie

    2014-01-01

    Mantle cell lymphoma (MCL) is usually an aggressive disease. However, a few patients do have an "indolent" evolution (iMCL) defined by a long survival time without intensive therapy. Many studies highlight the prognostic role of additional genetic abnormalities, but these abnormalities are not routinely tested for and do not yet influence the treatment decision. We aimed to evaluate the prognostic impact of these additional abnormalities detected by conventional cytogenetic testing, as well as their relationships with the clinical characteristics and their value in identifying iMCL. All consecutive MCL cases diagnosed between 1995 and 2011 at four institutions were retrospectively selected on the basis of an informative karyotype with a t(11;14) translocation at the time of diagnosis. A total of 125 patients were included and followed for an actual median time of 35 months. The median overall survival (OS) and survival without treatment (TFS) were 73.7 and 1.3 months, respectively. In multivariable Cox models, a high mantle cell lymphoma international prognostic index score, a complex karyotype, and blastoid morphology were independently associated with a shortened OS. Spleen enlargement, nodal presentation, extra-hematological involvement, and complex karyotypes were associated with shorter TFS. A score based on these factors allowed for the identification of "indolent" patients (median TFS 107 months) from other patients (median TFS: 1 month). In conclusion, in this multicentric cohort of MCL patients, a complex karyotype was associated with a shorter survival time and allowed for the identification of iMCL at the time of diagnosis. Copyright © 2013 Wiley Periodicals, Inc.

  7. Fragments of Time

    DEFF Research Database (Denmark)

    Christiansen, Steen Ledet

    Time travel films necessarily fragment linear narratives, as scenes are revisited with differences from the first time we saw it. Popular films such as Back to the Future mine comedy from these visitations, but there are many different approaches. One extreme is Chris Marker's La Jetée - a film...... made almost completely of still images, recounting the end of the world. These stills can be viewed as fragments that have survived the end of the world and now provide the only access to the events that occured. Shane Carruth's Primer has a different approach to time travel, the narrative diegesis...

  8. Time trends in incidence rates and survival of newly diagnosed stage IV breast cancer by tumor histology: a population-based analysis.

    Science.gov (United States)

    Di Meglio, Antonio; Freedman, Rachel A; Lin, Nancy U; Barry, William T; Metzger-Filho, Otto; Keating, Nancy L; King, Tari A; Sertoli, Mario Roberto; Boccardo, Francesco; Winer, Eric P; Vaz-Luis, Ines

    2016-06-01

    Few contemporary data are available that compare incidence and survival of metastatic breast cancer between ductal and lobular carcinomas. Using the Surveillance, Epidemiology, and End Results-9 registries, we identified 10,639 patients with de novo metastatic breast cancer diagnosed from 1990 to 2011. Annual age-adjusted incidence rates and annual percent changes (APCs) were analyzed. Multivariable Cox regression models were used to investigate the impact of year of diagnosis and histology on overall survival. 9250 (86.9 %) patients had ductal and 1389 (13.1 %) had lobular carcinomas. Metastatic breast cancer incidence increased slightly over time for ductal (APC = +1.7, 95 % confidence interval (CI) = +1.0 to +2.4) and lobular carcinomas (APC = +3.0, 95 % CI = +1.8 to +4.3). Median overall survival was 22 months among the whole cohort. More recent year of diagnosis was associated with better overall survival only for patients with ductal carcinomas (interaction p value = 0.006), with an adjusted hazard ratio of death for every five-year increment in the date of diagnosis of 0.93 (95 % CI =  0.91-0.95) among ductal carcinomas, compared with 1.05 (95 % CI = 0.95-1.10) among lobular carcinomas. Overall survival was longer for lobular versus ductal carcinomas (28 versus 21 months, respectively; adjusted hazard ratio of death = 0.93, 95 % CI = 0.87-0.99), but the magnitude of this effect was attenuated among the cohort restricted to hormone receptor-positive tumors. In this population-based analysis, incidence rates of metastatic breast cancer at presentation increased slightly over time for both histologies, and particularly for lobular tumors. A modest improvement in metastatic breast cancer median overall survival was observed, but was apparently limited to ductal carcinomas.

  9. Long-term time trends in incidence, survival and mortality of lymphomas by subtype among adults in Manitoba, Canada: a population-based study using cancer registry data.

    Science.gov (United States)

    Ye, Xibiao; Mahmud, Salaheddin; Skrabek, Pamela; Lix, Lisa; Johnston, James B

    2017-07-17

    To examine 30-year time trends in incidence, survival and mortality of lymphomas by subtype in Manitoba, Canada. Lymphoma cases diagnosed between 1984 and 2013 were classified according to the 2008 WHO classification system for lymphoid neoplasms. Death data (1984-2014) were obtained from the Manitoba Vital Statistics Agency. To examine time trends in incidence and mortality, we used joinpoint regression to estimate annual percentage change and average annual percentage change. Age-period-cohort modelling was conducted to measure the effects of age, period and cohort on incidence and mortality time trends. We estimated age-specific and standardised 5-year relative survival and used Poisson regression model to test time trends in relative survival. Total Hodgkin lymphoma (HL) incidence in men and women was stable during the study period. Age-standardised total non-Hodgkin lymphoma (NHL) incidence increased by 4% annually until around 2000, and the trend varied by sex and NHL subtype. Total HL mortality continuously declined (by 2.5% annually in men and by 2.7% annually in women), while total NHL mortality increased (by 4.4% annually in men until 1998 and by 3.2% annually in women until 2001) and then declined (by 3.6% annually in men and by 2.5% annually in women). Age-standardised 5-year relative survival for HL improved from 72.6% in 1984-1993 to 85.8% in 2004-2013, and for NHL from 57.0% in 1984-1993 to 67.5% in 2004-2013. Survival improvement was also noted for NHL subtypes, although the extent varied, with the greatest improvement for follicular lymphoma (from 65.3% in 1984-1993 to 87.6% in 2004-2013). Time trends were generally consistent with those reported in other jurisdictions in total HL and NHL incidence, but were unique in incidence for HL and for NHL subtypes chronic/small lymphocytic leukaemia/lymphoma, diffuse large B cell lymphoma and follicular lymphoma. Survival improvements and mortality reductions were seen for HL and NHL in both sexes.

  10. Dynamic assessment of Capparis spinosa buds on survival of periodontal ligament cells using a real-time cell analysis method.

    Science.gov (United States)

    Ozan, F; Özan, Ü; Oktay, E A; Toptas, O; Özdemir, H; KürÞat, Er

    2015-01-01

    Tooth avulsion is the most severe type of traumatic dental injuries and it results in the complete displacement of the tooth out of its socket in alveolar bone. Reimplantation of the tooth is considered to be a best treatment modality due to its biological and psychological advantages. Its prognosis depends on the extra alveolar time, the storage medium, and the patient's general health. The aim of this study was to evaluate the effect of Capparis spinosa (C. spinosa) in maintaining the viability of human periodontal ligament (PDL) cells using a real-time cell analysis method. Periodontal ligament cells were obtained from healthy human third molars extracted for orthodontic purposes. The storage media tested were: Dulbecco's Modified Eagle Medium (DMEM), C. spinosa, Hank's Balanced Salt Solution (HBSS), and light milk. A real-time cell analyzer system was used to evaluate cell viability. After seeding cell suspensions into the wells of the E-plate 96, PDL cells were treated with each of tested media and monitored for every 5 min for 26 h. Statistical analysis of the data was accomplished using one-way analysis of variance complemented by the Tukey test. The level of significance was set at P spinosa groups had significantly higher cell index values compared with the HBSS and light milk (P spinosa showed better results than DMEM (control), but this difference was not found statistically significant. Capparis spinosa can be a suitable, alternative storage medium for avulsed teeth.

  11. Eight-Year Retrospective Study of the Critical Time Lapse between Root Canal Completion and Crown Placement: Its Influence on the Survival of Endodontically Treated Teeth.

    Science.gov (United States)

    Pratt, Isaac; Aminoshariae, Anita; Montagnese, Thomas A; Williams, Kristin A; Khalighinejad, Navid; Mickel, Andre

    2016-11-01

    The purpose of this study was to investigate the effects of factors associated with various coronal restorative modalities after root canal treatment (RCT) on the survival of endodontically treated teeth (ETT) and to assess the effect of time lapse between RCT and crown placement after RCT to form a tooth loss hazard model. Computerized analysis was performed for all patients who received posterior RCT from 2008 to 2016 in the graduate endodontic department. Data collected included dates of RCT, type of post-endodontic restoration, and time of extraction if extracted. Teeth that received crown after RCT were also divided into 2 groups: receiving crown before 4 months and after 4 months after RCT. Data were analyzed by using Kaplan-Meier log-rank test and Cox regression model (α = 0.05) by using SPPS Statistic 21. Type of restoration after RCT significantly affected the survival of ETT (P = .001). ETT that received composite/amalgam buildup restorations were 2.29 times more likely to be extracted compared with ETT that received crown (hazard ratio, 2.29; confidence interval, 1.29-4.06; P = .005). Time of crown placement after RCT was also significantly correlated with survival rate of ETT (P = .001). Teeth that received crown 4 months after RCT were almost 3 times more likely to get extracted compared with teeth that received crown within 4 months of RCT (hazard ratio, 3.38; confidence interval, 1.56-6.33; P = .002). Patients may benefit by maintaining their natural dentition by timely placement of crown after RCT, which otherwise may have been extracted and replaced by implant because of any delay in crown placement. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  12. [Effects of fuzheng jianpi decoction combined chemotherapy on the quality of life and the survival time of children with solid tumor].

    Science.gov (United States)

    Shi, Xue; Zhu, Xiu-Dan; Wang, Huan-Ming

    2012-09-01

    To study the effects of Fuzheng Jianpi Decoction (FJD) combined chemotherapy on the quality of life (QOL) and the survival time of children with solid tumor. Recruited were 167 solid tumor children patients at Department of Tumor, Beijing Children's Hospital from Jan. 2005 to Jan. 2008. They were randomly assigned to the treatment group (83 cases) and the control group (84 cases) according to the random digit table. All had chemotherapy. Those in the treatment group additionally took FJD, 50 -100 mL each time, twice daily. After chemotherapy those in the treatment group took modified FJD. The WBC, Hb, and PLT were detected in all patients before treatment, 6 months after treatment, and 1 year after treatment. The 1-, 2-, and 3-year QOL, 3-year survival rate, and the survival life of dead children patients were observed. Compared with the control group of the same period, the 6-month and 1-year WBC and Hb increased, the 1-year PLT increased in the treatment group, showing statistical difference (Pchildren was prolonged in the treatment group, showing statistical difference (Pchemotherapy could effectively improve the QOL of solid tumor children patients, elevate their survival rate, and prolong their life spans.

  13. A geographic study of West Nile virus in humans, dead corvids and mosquitoes in Ontario using spatial scan statistics with a survival time application.

    Science.gov (United States)

    Thomas-Bachli, A L; Pearl, D L; Berke, O; Parmley, E J; Barker, I K

    2017-11-01

    Surveillance of West Nile virus (WNv) in Ontario has included passive reporting of human cases and testing of trapped mosquitoes and dead birds found by the public. The dead bird surveillance programme was limited to testing within a public health unit (PHU) until a small number of birds test positive. These dead corvid and mosquito surveillance programmes have not been compared for their ability to provide early warning in geographic areas where human cases occur each year. Spatial scan statistics were applied to time-to-event survival data based on first cases of WNv in found dead corvids, mosquitoes and humans. Clusters identified using raw data were compared to clusters based on model-adjusted survival times to evaluate whether geographic and sociodemographic factors influenced their distribution. Statistically significant (p space-time clusters of PHUs with faster time to detection were found using each surveillance data stream. During 2002-2004, the corvid surveillance programme outperformed the mosquito programme in terms of time to WNv detection, while the clusters of first-positive mosquito pools were more spatially similar to first human cases. In 2006, a cluster of first-positive dead corvids was located in northern PHUs and preceded a cluster of early human cases that was identified after controlling for the influence of geographic region and sociodemographic profile. © 2017 Blackwell Verlag GmbH.

  14. Surviving death-anxieties in liquid modern times: examining Zygmunt Bauman's cultural theory of death and dying.

    Science.gov (United States)

    Higo, Masa

    2012-01-01

    Despite his prominence as a leading contemporary social theorist, Zygmunt Bauman's long-term writing on the cultural theory of death and dying has largely been overlooked in the sociological literature of death and dying, particularly in the United States. Bauman uniquely theorizes how we survive death-anxieties today: Contemporary, liquid modern culture has engaged us in ceaseless pursuit of the unattainable consumer sensation of bodily fitness as a way to suppress and thus survive our death-anxieties. Bauman also argues that the prevalence of this cultural formula to survive death-anxieties has simultaneously increased, more than ever before in social history, the volume of individual responsibility for restlessly coping with existential anxieties in the societies of consumers. While unique and insightful, his theoretical argument has a limitation; largely succeeding Freud's classic view of mortality, Bauman's contemporary theory may lead us to neglect potentially important social, cultural, and historical variations in how mortality has been understood.

  15. Competitive Moves over Time

    DEFF Research Database (Denmark)

    Antero, Michelle; Hedman, Jonas; Henningsson, Stefan

    2014-01-01

    This paper applies the Red Queen theory to explain how organizations utilize various sourcing arrangements in order to compete in an evolutionary arms race where only the strongest competitors will survive. This case study incorporates competition and views sourcing strategies as a means to improve...... its viability to survive in the marketplace. The study begins with a review of sourcing literature to position the Red Queen theory within the sourcing literature. It subsequently applies the framework to a case study of SAP AG to illustrate how sourcing strategies changed over time in response...

  16. Mercury and drought along the lower Carson River, Nevada: IV. Snowy egret post-fledging dispersal, timing of migration and survival, 2002–2004

    Science.gov (United States)

    Henny, Charles J.; Hill, Elwood F.; Grove, Robert A.; Chelgren, Nathan; Haggerty, Patricia K.

    2017-01-01

    This telemetry study is an extension of our 1997–2006 research on historical mercury contamination on snowy egrets (Egretta thula) up to ~ 20 days of age. Findings from initial studies at the mercury-contaminated Carson River colony at Lahontan Reservoir (LR) and a similar-sized reference (REF) colony on the Humboldt River included mercury-related physiological, biochemical, histopathological and reproductive effects up to ~20 days of age; with poor water years (2000–04), i.e., reduced prey availability, exacerbating effects. Herein, we compare timing of dispersal and migration at LR vs. REF, but the primary question now addressed is “whether survival of young mercury-exposed snowy egrets from LR would be further compromised beyond ~20 days of age? ” Based upon telemetry signals until 90–110 days of age (including dead bird counts and survival rate estimates), we conclude that mercury did not further compromise survival. Dead bird counts and survival rate estimates included time in the colony when fed by adults, plus the critical period when young dispersed from the colony to forage independently. The extended drought during this 3-year study was most critical in 2002 when production of ~20 d old egrets at LR was only 0.24 young/nest. In 2002, survival rates were low at both colonies and we documented the highest counts of dead egrets for both colonies. We suggest the losses in 2002 beyond 20 days of age were more a function of prey availability influenced by drought than exposure to mercury, especially at LR, because higher mercury concentrations, higher survival rates and fewer dead birds were documented at LR in 2003 when water conditions improved. Furthermore, total mercury (THg) in blood in 2003 was more than double 2002 (geometric mean, 3.39 vs 1.47 µg/g wet weight (ww). This higher THg exposure at LR in 2003 was associated with a redistribution of parent and post-dispersal feeding activities upstream (where there was higher mercury from historic

  17. Mercury and drought along the lower Carson River, Nevada: IV. Snowy egret post-fledging dispersal, timing of migration and survival, 2002-2004.

    Science.gov (United States)

    Henny, Charles J; Hill, Elwood F; Grove, Robert A; Chelgren, Nathan D; Haggerty, Patricia K

    2017-01-01

    This telemetry study is an extension of our 1997-2006 research on historical mercury contamination on snowy egrets (Egretta thula) up to ~ 20 days of age. Findings from initial studies at the mercury-contaminated Carson River colony at Lahontan Reservoir (LR) and a similar-sized reference (REF) colony on the Humboldt River included mercury-related physiological, biochemical, histopathological and reproductive effects up to ~20 days of age; with poor water years (2000-04), i.e., reduced prey availability, exacerbating effects. Herein, we compare timing of dispersal and migration at LR vs. REF, but the primary question now addressed is "whether survival of young mercury-exposed snowy egrets from LR would be further compromised beyond ~20 days of age? " Based upon telemetry signals until 90-110 days of age (including dead bird counts and survival rate estimates), we conclude that mercury did not further compromise survival. Dead bird counts and survival rate estimates included time in the colony when fed by adults, plus the critical period when young dispersed from the colony to forage independently. The extended drought during this 3-year study was most critical in 2002 when production of ~20d old egrets at LR was only 0.24 young/nest. In 2002, survival rates were low at both colonies and we documented the highest counts of dead egrets for both colonies. We suggest the losses in 2002 beyond 20 days of age were more a function of prey availability influenced by drought than exposure to mercury, especially at LR, because higher mercury concentrations, higher survival rates and fewer dead birds were documented at LR in 2003 when water conditions improved. Furthermore, total mercury (THg) in blood in 2003 was more than double 2002 (geometric mean, 3.39 vs 1.47µg/g wet weight (ww). This higher THg exposure at LR in 2003 was associated with a redistribution of parent and post-dispersal feeding activities upstream (where there was higher mercury from historic mining

  18. Application of Survival Analysis to Study Timing and Probability of Outcome Attainment by a Community College Student Cohort

    Science.gov (United States)

    Mourad, Roger; Hong, Ji-Hee

    2008-01-01

    This study applies competing risks survival analysis to describe outcome attainment for an entire cohort of students who first attended a Midwestern community college in the Fall Semester 2001. Outcome attainment included transfer to a four-year institution, degree/ certificate attainment from the community college under study, and transfer to a…

  19. The Art of Creating Attractive Consumer Experiences at the Right Time: Skills Marketers Will Need to Survive and Thrive

    Directory of Open Access Journals (Sweden)

    Lemon Katherine N.

    2016-11-01

    Full Text Available New technologies have made today’s marketing faster, more mobile, more location-based, more digital, more virtual, and more automatized than ever. In this new world, marketers need to be “real-time relevant” – to gain awareness, to change perceptions and to spur action. They need to have their content in the right channel, format, time and context – from a consumer’s perspective. Only then do they at least have a chance of the consumer attending to the information and being influenced by it. In such an environment new skills and competences are required. The amount of available data has virtually exploded. To gain any perspective or apparent “control” in these environments, successful managers must embrace the complexity and learn to analyze, integrate and interpret all this data. A critical skill for marketers will be to identify the metrics that best reflect the desired outcomes of the organization and that sufficiently reflect specific indicators of critical processes. Furthermore, insights from other disciplines such as architecture, design, information-processing, biology or engineering will be important for creating customer experiences. The marketer of the future will need to be supremely curious and creative and to balance and integrate different worlds. It will all come down to delivering memorable and lasting experiences in a constantly and fast changing environment.

  20. Hemopathologic predisposition and survival time under continuous gamma irradiation: responses mediated by altered radiosensitivity of hemopoietic progenitors

    Energy Technology Data Exchange (ETDEWEB)

    Seed, T.M.; Kaspar, L.V.; Tolle, D.V.; Fritz, T.E.

    1982-01-01

    These marked differences in radiosensitivity of individual animals within a relatively homogeneous, healthy pure bred group, as manifested by varying survival patterns and pathologic tendencies, have stimulated studies concerning the cellular bases of these responses. In previous studies, as in this one, the authors have attempted to characterize the cellular processes of hemopoietic recovery, an early occurring event characteristically observed in a select subgroup of MPD dogs exhibiting prolonged course of survival and a tendency to myeloproliferative disorders (MPD). Hemopoietic recovery appears to be a broadly based process as indicated by: (a) increased concentrations of blood granulocytes; (b) expanded granulocyte reserves; and (c) increased concentration of hemopoietic progenitors in the marrow. The intent of the present study was to examine the possibility that the cellular basis of hemopoietic recovery resides in the acquisition of increased radioresistance by hemopoietic progenitors, i.e., the suspected cellular targets of the hemopathic effects of ionizing irradiation.

  1. Instrumental variables estimation of exposure effects on a time-to-event response using structural cumulative survival models

    DEFF Research Database (Denmark)

    Martinussen, T.; Vansteelandt, S.; Tchetgen, E. J. Tchetgen

    2016-01-01

    The use of instrumental variables for estimating the effect of an exposure on an outcome is popular in econometrics, and increasingly so in epidemiology. This increasing popularity may be attributed to the natural occurrence of instrumental variables in observational studies that incorporate...... elements of randomization, either by design or by nature (e.g., random inheritance of genes). Instrumental variables estimation of exposure effects is well established for continuous outcomes and to some extent for binary outcomes. It is, however, largely lacking for time-to-event outcomes because......-parametric variant of the instrumental variables additive hazards model. We propose a class of recursive instrumental variable estimators for these exposure effects, and derive their large sample properties along with inferential tools. We examine the performance of the proposed method in simulation studies...

  2. Relationship Between Radiation Treatment Time and Overall Survival After Induction Chemotherapy for Locally Advanced Head-and-Neck Carcinoma: A Subset Analysis of TAX 324

    Energy Technology Data Exchange (ETDEWEB)

    Sher, David J., E-mail: dsher@partners.org [Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women' s Hospital, Boston, MA (United States); Posner, Marshall R. [Division of Hematology/Oncology, Mount Sinai School of Medicine, New York, NY (United States); Tishler, Roy B. [Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women' s Hospital, Boston, MA (United States); Sarlis, Nicholas J. [Sanofi-Aventis US, Bridgewater, NJ (United States); Haddad, Robert I. [Department of Medical Oncology, Dana-Farber Cancer Institute and Department of Medicine, Brigham and Women' s Hospital, Boston, MA (United States); Holupka, Edward J. [Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Boston, MA (Israel); Devlin, Phillip M. [Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women' s Hospital, Boston, MA (United States)

    2011-12-01

    Purpose: To analyze the relationship between overall survival (OS) and radiation treatment time (RTT) and overall treatment time (OTT) in a well-described sequential therapy paradigm for locally advanced head-and-neck carcinoma (LAHNC). Methods and Materials: TAX 324 is a Phase III study comparing TPF (docetaxel, cisplatin, and fluorouracil) with PF (cisplatin and fluorouracil) induction chemotherapy (IC) in LAHNC patients; both arms were followed by carboplatin-based chemoradiotherapy (CRT). Prospective radiotherapy quality assurance was performed. This analysis includes all patients who received three cycles of IC and a radiation dose of {>=} 70 Gy. Radiotherapy treatment time was analyzed as binary ({<=} 8 weeks vs. longer) and continuous (number of days beyond 8 weeks) functions. The primary analysis assessed the relationship between RTT, OTT, and OS, and the secondary analysis explored the association between treatment times and locoregional recurrence (LRR). Results: A total of 333 (of 501) TAX 324 patients met the criteria for inclusion in this analysis. There were no significant differences between the treatment arms in baseline or treatment characteristics. On multivariable analysis, PF IC, World Health Organization performance status of 1, non-oropharynx site, T3/4 stage, N3 status, and prolonged RTT (hazard ratio 1.63, p = 0.006) were associated with significantly inferior survival. Performance status, T3/4 disease, and prolonged RTT (odds ratio 1.68, p = 0.047) were independently and negatively related to LRR on multivariable analysis, whereas PF was not. Overall treatment time was not independently associated with either OS or LRR. Conclusions: In this secondary analysis of the TAX 324 trial, TPF IC remains superior to PF IC after controlling for radiotherapy delivery time. Even with optimal IC and concurrent chemotherapy, a non-prolonged RTT is a crucial determinant of treatment success. Appropriate delivery of radiotherapy after IC remains essential

  3. Survival time outcomes in randomized, controlled trials and meta-analyses: the parallel universes of efficacy and cost-effectiveness.

    Science.gov (United States)

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

    2011-01-01

    Many regulatory agencies require that manufacturers establish both efficacy and cost-effectiveness. The statistical analysis of the randomized, controlled trial (RCT) outcomes should be the same for both purposes. The question addressed by this article is the following: for survival outcomes, what is the relationship between the statistical analyses used to support inference and the statistical model used to support decision making based on cost-effectiveness analysis (CEA)? We performed a review of CEAs alongside trials and CEAs based on a synthesis of RCT results, which were submitted to the National Institute for Health and Clinical Excellence (NICE) Technology Appraisal program and included survival outcomes. We recorded the summary statistics and the statistical models used in both efficacy and cost-effectiveness analyses as well as procedures for model diagnosis and selection. In no case was the statistical model for efficacy and CEA the same. For efficacy, relative risks or Cox regression was used. For CEA, the common practice was to fit a parametric model to the control arm, then to apply the hazard ratio from the efficacy analysis to predict the treatment arm. The proportional hazards assumption was seldom checked; the choice of model was seldom based on formal criteria, and uncertainty in model choice was seldom addressed and never propagated through the model. Both inference and decisions based on CEAs should be based on the same statistical model. This article shows that for survival outcomes, this is not the case. In the interests of transparency, trial protocols should specify a common procedure for model choice for both purposes. Further, the sufficient statistics and the life tables for each arm should be reported to improve transparency and to facilitate secondary analyses of results of RCTs. Copyright © 2011 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  4. A race against time: can CO-OPs and provider start-ups survive in the health insurance marketplaces?

    Science.gov (United States)

    Eggbeer, Bill

    2015-12-01

    > The Affordable Care Act's state and federal health insurance marketplaces, designed to provide affordable insurance coverage to individuals and small groups, are proving hostile territory to new market entrants. Efforts to inject competition into the marketplaces are being challenged by the wide-scale withdrawal o consumer-operated and oriented plans (CO-OPs). Meanwhile, premiums appear likely to increase for consumers as plans seek to balance medical losses. Flaws in the "Three R's" (reinsurance, risk corridors, and risk-adjustment) program are viewed as a threat to the survival of CO-OPs and start-ups.

  5. Radiotherapy timing in the treatment of limited-stage small cell lung cancer: the impact of thoracic and brain irradiation on survival.

    Science.gov (United States)

    Scotti, Vieri; Meattini, Icro; Franzese, Ciro; Saieva, Calogero; Bertocci, Silvia; Meacci, Fiammetta; Furfaro, Ilaria; Scartoni, Daniele; Cecchini, Sara; Desideri, Isacco; Ferrari, Katia; Bruni, Alessio; De Luca Cardillo, Carla; Bastiani, Paolo; Agresti, Benedetta; Mangoni, Monica; Livi, Lorenzo; Biti, Giampaolo

    2014-01-01

    Small cell lung cancer is an aggressive histologic subtype of lung cancer in which the role of chemotherapy and radiotherapy has been well established in limited-stage disease. We retrospectively reviewed a series of limited-stage small cell lung cancers treated with chemotherapy and thoracic and brain radiotherapy. A total of 124 patients affected by limited-stage small cell lung cancer has been treated over 10 years in our Institute. Fifty-three patients (42.8%) had concomitant radio-chemotherapy treatment and 71 patients (57.2%) a sequential treatment. Eighty-eight patients (70.9%) underwent an association of a platinum-derived drug (cisplatinum or carboplatinum) and etoposide. Prophylactic cranial irradiation was planned in all patients with histologically proven complete response to primary radio-chemotherapy. With a mean follow-up of 2.2 years, complete response was obtained in 50.8% of cases. We found a significant difference between different radio-chemotherapy association approaches (P = 0.007): percentages of overall survival were respectively 10.0%, 12.9% and 5.6% in early, late concomitant and sequential radio-chemotherapy timing. Cranial prophylaxis did not seem to influence overall survival (P = 0.21) or disease-free survival for local relapse (P = 0.34). Concomitant radio-chemotherapy is the best approach according to our experience. Our results show a benefit of prophylactic cranial irradiation in distant metastasis-free survival.

  6. Exploratory Analysis of Time from HIV Diagnosis to ART Start, Factors and effect on survival: A longitudinal follow up study at seven teaching hospitals in Ethiopia.

    Science.gov (United States)

    Teklu, Alula M; Delele, Kesetebirhan; Abraha, Mulu; Belayhun, Bekele; Gudina, Esayas Kebede; Nega, Abiy

    2017-02-01

    The HIV care in Ethiopia has reached 79% coverage. The timeliness of the care provided at the different levels in the course of the disease starting from knowing HIV positive status to ART initiation is not well known. This study intends to explore the timing of the care seeking, the care provision and associated factors. This is a longitudinal follow-up study at seven university hospitals. Patients enrolled in HIV care from September 2005 to December 2013 and aged ≥14 years were studied. Different times in the cascade of HIV care were examined including the duration from date HIV diagnosed to enrollment in HIV care, duration from enrollment to eligibility for ART and time from eligibility to initiation of ART. Ordinal logistic regression was used to investigate their determinants while the effect of these periods on survival of patients was determined using cox-proportional hazards regression. 4159 clients were studied. Time to enrollment after HIV test decreased from 39 days in 2005 to 1 day after 2008. It took longer if baseline CD4 was higher, and eligibility for ART was assessed late. Young adults, lower baseline CD4, HIV diagnosisART initiation. Male gender, advanced disease stage and lower baseline CD4 were consistent risk factors for mortality. Time to enrollment and duration of ART eligibility assessment as well as ART initiation time after eligibility is improving. Further study is required to identify why mortality is slightly increasing after 2010.

  7. Social familiarity reduces reaction times and enhances survival of group-living predatory mites under the risk of predation.

    Directory of Open Access Journals (Sweden)

    Markus Andreas Strodl

    Full Text Available Social familiarity, which is based on the ability to recognise familiar conspecific individuals following prior association, may affect all major life activities of group-living animals such as foraging, reproduction and anti-predator behaviours. A scarcely experimentally tested explanation why social familiarity is beneficial for group-living animals is provided by limited attention theory. Limited attention theory postulates that focusing on a given task, such as inspection and assessment of unfamiliar group members, has cognitive and associated physiological and behavioural costs with respect to the attention paid to other tasks, such as anti-predator vigilance and response. Accordingly, we hypothesised that social familiarity enhances the anti-predator success of group-living predatory mites, Phytoseiulus persimilis, confronted with an intraguild predator, the predatory mite Amblyseius andersoni.We videotaped and analysed the response of two P. persimilis larvae, held in familiar or unfamiliar pairs, to attacks by a gravid A. andersoni female, using the behavioural analyses software EthoVision Pro®. Familiar larvae were more frequently close together, reacted more quickly to predator attacks, survived more predator encounters and survived longer than unfamiliar larvae.In line with the predictions of limited attention theory, we suggest that social familiarity improves anti-predator behaviours because it allows prey to shift attention to other tasks rather than group member assessment.

  8. THE EFFECT OF CAROVERINE AND ITS COMBINATION WITH AMINOOXYACETIC ACID ON SURVIVAL TIME OF MICE WITH EXPERIMENTAL TETANUS

    Directory of Open Access Journals (Sweden)

    Indira Mujezinović

    2013-03-01

    Full Text Available Tetanus is a disease that occurs in humans and various animal species worldwide. Tetanus toxin, after binding itself to nerve structures in the spinal cord, blocking the release of inhibitory transmitors which results in predominance of excitatory transmitors, and this manifestes itself in skeletal muscle spasm. In theory, inhibition of excitatory transmission can try to antagonize a number of ways: by stimulating inhibitory transmission with application inhibitory transmitors, inhibition of excitatory transmission by application of antagonists of excitatory transmitors and combination of antagonists of excitatory transmitors. Bearing this in mind, we attempted to normalize the disorders by tetanus toxin with the use of caroverine, an antagonist of excitatory transmitors, alone and in combination with aminooxyacetic acid (substance that increases the level of GABA. Experiments were conducted on albino mice of both sexes, weight 20-25 g. The experimental tetanus was induced by application of tetanus toxin. The application of caroverine and combination with aminooxyacetic acid was carried out 24 hours after application of tetanus toxin, once per day, until the death. Caroverine, given alone in a dose of 1,2 mg/kg significantly prolonged the LD50 period of mice with experimental tetanus, so the obtained results can be said that its application only at this dose proved to be effective. The combination with aminooxyacetic acid was gave an insignificant extension of mice’s dying time with experimental tetanus in the trial, compared to the control group. Key words: tetanus, tetanus toxin, transmitors, caroverine, aminooxyacetic acid

  9. The Life and Times of Parasites: Rhythms in Strategies for Within-host Survival and Between-host Transmission.

    Science.gov (United States)

    Reece, Sarah E; Prior, Kimberley F; Mideo, Nicole

    2017-12-01

    Biological rhythms are thought to have evolved to enable organisms to organize their activities according to the earth's predictable cycles, but quantifying the fitness advantages of rhythms is challenging and data revealing their costs and benefits are scarce. More difficult still is explaining why parasites that live exclusively within the bodies of other organisms have biological rhythms. Rhythms exist in the development and traits of parasites, in host immune responses, and in disease susceptibility. This raises the possibility that timing matters for how hosts and parasites interact and, consequently, for the severity and transmission of diseases. Here, we take an evolutionary ecological perspective to examine why parasites exhibit biological rhythms and how their rhythms are regulated. Specifically, we examine the adaptive significance (evolutionary costs and benefits) of rhythms for parasites and explore to what extent interactions between hosts and parasites can drive rhythms in infections. That parasites with altered rhythms can evade the effects of control interventions underscores the urgent need to understand how and why parasites exhibit biological rhythms. Thus, we contend that examining the roles of biological rhythms in disease offers innovative approaches to improve health and opens up a new arena for studying host-parasite (and host-parasite-vector) coevolution.

  10. Endogenous TSH levels at the time of {sup 131}I ablation do not influence ablation success, recurrence-free survival or differentiated thyroid cancer-related mortality

    Energy Technology Data Exchange (ETDEWEB)

    Vrachimis, Alexis; Riemann, Burkhard [University Hospital Muenster, Department of Nuclear Medicine, Muenster (Germany); Maeder, Uwe; Reiners, Christoph [University of Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); Verburg, Frederik A. [University of Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); RWTH University Hospital Aachen, Department of Nuclear Medicine, Aachen (Germany)

    2016-02-15

    Based on a single older study it is established dogma that TSH levels should be ≥30 mU/l at the time of postoperative {sup 131}I ablation in differentiated thyroid cancer (DTC) patients. We sought to determine whether endogenous TSH levels, i.e. after levothyroxine withdrawal, at the time of ablation influence ablation success rates, recurrence-free survival and DTC-related mortality. A total of 1,873 patients without distant metastases referred for postoperative adjuvant {sup 131}I therapy were retrospectively included from 1991 onwards. Successful ablation was defined as stimulated Tg <1 μg/l. Age, gender and the presence of lymph node metastases were independent determinants of TSH levels at the time of ablation. TSH levels were not significantly related to ablation success rates (p = 0.34), recurrence-free survival (p = 0.29) or DTC -elated mortality (p = 0.82), but established risk factors such as T-stage, lymph node metastases and age were. Ablation was successful in 230 of 275 patients (83.6 %) with TSH <30 mU/l and in 1,359 of 1,598 patients (85.0 %) with TSH ≥30 mU/l. The difference was not significant (p = 0.55). Of the whole group of 1,873 patients, 21 had recurrent disease. There were no significant differences in recurrence rates between patients with TSH <30 mU/l and TSH ≥30 mU/l (p = 0.16). Ten of the 1,873 patients died of DTC. There were no significant differences in DTC-specific survival between patients with TSH <30 mU/l and TSH ≥30 mU/l (p = 0.53). The precise endogenous TSH levels at the time of {sup 131}I ablation are not related to the ablation success rates, recurrence free survival and DTC related mortality. The established dogma that TSH levels need to be ≥30 mU/l at the time of {sup 131}I ablation can be discarded. (orig.)

  11. Science takes time : families take time!

    OpenAIRE

    Hultberg, Kirsti Baird

    2000-01-01

    Who has time to have a family ? Scientists are the «heroes» of our time. Science takes time - Families take time. Who gives time ? My case -study consists of interviews with scientific workers of both sexes. They are asked how they juggle the time required in the production of scientific knowledge and family life. My findings indicate that it is women, who give of their time.

  12. Predicting treatment effect from surrogate endpoints and historical trials: an extrapolation involving probabilities of a binary outcome or survival to a specific time.

    Science.gov (United States)

    Baker, Stuart G; Sargent, Daniel J; Buyse, Marc; Burzykowski, Tomasz

    2012-03-01

    Using multiple historical trials with surrogate and true endpoints, we consider various models to predict the effect of treatment on a true endpoint in a target trial in which only a surrogate endpoint is observed. This predicted result is computed using (1) a prediction model (mixture, linear, or principal stratification) estimated from historical trials and the surrogate endpoint of the target trial and (2) a random extrapolation error estimated from successively leaving out each trial among the historical trials. The method applies to either binary outcomes or survival to a particular time that is computed from censored survival data. We compute a 95% confidence interval for the predicted result and validate its coverage using simulation. To summarize the additional uncertainty from using a predicted instead of true result for the estimated treatment effect, we compute its multiplier of standard error. Software is available for download. © 2011, The International Biometric Society No claim to original US government works.

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

    Science.gov (United States)

    Pramukkul, Pensri; Svenkeson, Adam; Grigolini, Paolo

    2014-02-01

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

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

    Science.gov (United States)

    Pramukkul, Pensri; Svenkeson, Adam; Grigolini, Paolo

    2014-02-01

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

  15. Endoscopic Ultrasound-Guided Direct Portal Pressure Measurement Using a Digital Pressure Wire with Real-Time Remote Display: A Survival Study.

    Science.gov (United States)

    Schulman, Allison R; Thompson, Christopher C; Ryou, Marvin

    2017-10-01

    Portal hypertension is necessary for the development of most clinical complications of cirrhosis. We recently reported a novel, endoscopic ultrasound (EUS)-guided technique for direct portal pressure measurements using a digital pressure wire. The aims of this study were to (1) evaluate safety in an animal survival model and (2) compare direct portal vein (PV) versus transhepatic access of a first-order venule. Yorkshire pigs, weighing 40-55 kg. Procedures were performed under general anesthesia. PV was identified using a linear array echoendoscope and accessed with a 22-G fine needle aspiration needle preloaded with a digital pressure wire. Access was confirmed by portal venography. Mean digital pressure measurements were recorded over 30 seconds, and again after accessing a first-order portal venule in a transhepatic manner. Procedure times and video logs were maintained throughout. Animals were survived for 2 weeks. Repeat portal pressure measurements were performed before euthanasia and necropsy. EUS-guided portal pressure measurements ranged from 3 to 11 mm Hg (mean 6.1) and were performed in a mean time of 214 seconds. There was no difference in measurement between the PV and first-order venule, or between baseline and 2-week follow-up. Five of 5 animals survived without incident. On necropsy, there was no evidence of thrombus or hemorrhage. This study represents the first survival study after EUS-guided direct portal pressure measurements using a digital pressure wire. This method appears safe, straightforward, and precise. Measurements of the PV and a first-order portal venule appear equivalent, and serial measurement seems feasible.

  16. Joint analyses of longitudinal and time-to-event data in research on aging: Implications for predicting health and survival

    Directory of Open Access Journals (Sweden)

    Konstantin G. Arbeev

    2014-11-01

    Full Text Available Longitudinal data on aging, health and longevity provide a wealth of information to investigate different aspects of the processes of aging and development of diseases leading to death. Statistical methods aimed at analyses of time-to-event data jointly with longitudinal measurements became known as the joint models (JM. An important point to consider in analyses of such data in the context of studies on aging, health, and longevity is how to incorporate knowledge and theories about mechanisms and regularities of aging-related changes that accumulate in the research field into respective analytic approaches. In the absence of specific observations of longitudinal dynamics of relevant biomarkers manifesting such mechanisms and regularities, traditional approaches have a rather limited utility to estimate respective parameters that can be meaningfully interpreted from the biological point of view. A conceptual analytic framework for these purposes, the stochastic process model of aging (SPM, has been recently developed in the biodemographic literature. It incorporates available knowledge about mechanisms of aging-related changes which may be hidden in the individual longitudinal trajectories of physiological variables and this allows for analyzing their indirect impact on risks of diseases and death. Despite, essentially, serving similar purposes, JM and SPM developed in parallel in different disciplines with very limited cross-referencing. Although there were several publications separately reviewing these two approaches, there were no publications presenting both these approaches in some detail. Here we overview both approaches jointly and provide some new modifications of SPM. We discuss the use of stochastic processes to capture biological variation and heterogeneity in longitudinal patterns and important and promising (but still largely underused applications of JM and SPM to predictions of individual and population mortality and health

  17. Sotrastaurin (AEB071) alone and in combination with cyclosporine A prolongs survival times of non-human primate recipients of life-supporting kidney allografts.

    Science.gov (United States)

    Bigaud, Marc; Wieczorek, Grazyna; Beerli, Christian; Audet, Maxime; Blancher, Antoine; Heusser, Christoph; Morris, Randall E; Wagner, Jürgen

    2012-01-27

    Sotrastaurin (STN), a novel oral protein kinase C inhibitor that inhibits early T-cell activation, was assessed in non-human primate recipients of life-supporting kidney allografts. Cynomolgus monkey recipients of life-supporting kidney allografts were treated orally with STN alone or in combination with cyclosporine A (CsA). STN monotherapy at 50 mg/kg once daily prolonged recipient survival times to the predefined endpoint of 29 days (n=2); when given at 25 mg/kg twice daily, the median survival time (MST) was 27 days (n=4). Neither once-daily monotherapy of STN 20 mg/kg nor CsA 20 mg/kg was effective (MST 6 days [n=2] and 7 days [n=5], respectively). In combination, however, STN 20 mg/kg and CsA 20 mg/kg prolonged MST to more than 100 days (n=5). By combining lower once-daily doses of STN (7 or 2 mg/kg) with CsA (20 mg/kg), MST was more than 100 (n=3) and 22 days (n=2), respectively. Neither in single-dose pharmacokinetic studies nor the transplant recipients were STN or CsA blood levels for combined treatment greater than when either drug was administered alone. STN blood levels in transplant recipients during combination therapy were dose related (20 mg/kg, 30-182 ng/mL; 7 mg/kg, 7-41 ng/mL; and 2 mg/kg, 3-5 ng/mL). STN at a daily dose of up to 20 mg/kg was relatively well tolerated. STN prolonged survival times of non-human primate kidney allograft recipients both as monotherapy and most effectively in combination with CsA. Pharmacokinetic interactions were not responsible for the potentiation of immunosuppressive efficacy by coadministering STN and CsA.

  18. L-carnitine is a survival factor for chilled storage of rooster semen for a long time.

    Science.gov (United States)

    Fattah, A; Sharafi, M; Masoudi, R; Shahverdi, A; Esmaeili, V

    2017-02-01

    Rooster sperm is sensitive to cooling, which restricts procedures to store sperms for extended periods of time for artificial insemination of commercial flocks. This study was conducted to evaluate the suitability of adding L-carnitine (LC) to chilled-storage of rooster sperm and its effects on sperm quality parameters and its fertility potential during storage at 5 °C. Pooled semen from roosters were divided into six equal aliquots and diluted with media supplemented with different concentrations of LC (0, 0.5, 1, 2, 4 and 8 mM LC). Diluted semen samples were cooled to 5 °C and stored over 48 h. Motility, viability, membrane functionality, lipid peroxidation and mitochondria activity of the sperm were assessed at 0, 24 and 48 h of storage. Moreover, fertility potential of chilled stored sperm was considered at 24 h of storage. While sperm quality was not affected by LC at the beginning of storage (0 h), supplementation of extender with 1 and 2 mM of LC significantly improved the percentage of sperm motility, viability, membrane integrity and mitochondria activity at 24 h and 48 h compared to other groups. Lipid peroxidation was significantly reduced in sperm samples diluted with 1 and 2 mM LC at 24 h (2.15 ± 0.52 nmol/ml and 2.21 ± 0.52 nmol/ml) and 48 h (3.42 ± 0.49 nmol/ml and 3.38 ± 0.49 nmol/ml) compared to other groups. Furthermore, fertility rates during artificial insemination using sperms cooled for 24 h in the presence of 1 and 2 mM LC were significantly higher (78%) than in the control group (64%). These findings suggest that optimum doses of LC could protect rooster sperm against cool storage-induced functional and structural damages. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Timing of therapeutic intervention determines functional and survival outcomes in a mouse model of late infantile batten disease.

    Science.gov (United States)

    Cabrera-Salazar, Mario A; Roskelley, Eric M; Bu, Jie; Hodges, Bradley L; Yew, Nelson; Dodge, James C; Shihabuddin, Lamya S; Sohar, Istvan; Sleat, David E; Scheule, Ronald K; Davidson, Beverly L; Cheng, Seng H; Lobel, Peter; Passini, Marco A

    2007-10-01

    Classical late infantile neuronal ceroid lipofuscinosis (cLINCL) is a monogenic disorder caused by the loss of tripeptidyl peptidase 1 (TPP1) activity as a result of mutations in CLN2. Absence of TPP1 results in lysosomal storage with an accompanying axonal degeneration throughout the central nervous system (CNS), which leads to progressive neurodegeneration and early death. In this study, we compared the efficacies of pre- and post-symptomatic injections of recombinant adeno-associated virus (AAV) for treating the cellular and functional abnormalities of CLN2 mutant mice. Intracranial injection of AAV1-hCLN2 resulted in widespread human TPP1 (hTPP1) activity in the brain that was 10-100-fold above wild-type levels. Injections before disease onset prevented storage and spared neurons from axonal degeneration, reflected by the preservation of motor function. Furthermore, the majority of CLN2 mutant mice treated pre-symptomatically lived for at least 330 days, compared with a median survival of 151 days in untreated CLN2 mutant controls. In contrast, although injection after disease onset ameliorated lysosomal storage, there was evidence of axonal degeneration, motor function showed limited recovery, and the animals had a median lifespan of 216 days. These data illustrate the importance of early intervention for enhanced therapeutic benefit, which may provide guidance in designing novel treatment strategies for cLINCL patients.

  20. Effect of temperature and relative humidity on the development times and survival of Synopsyllus fonquerniei and Xenopsylla cheopis, the flea vectors of plague in Madagascar.

    Science.gov (United States)

    Kreppel, Katharina S; Telfer, Sandra; Rajerison, Minoarisoa; Morse, Andy; Baylis, Matthew

    2016-02-11

    Plague, a zoonosis caused by Yersinia pestis, is found in Asia, the Americas but mainly in Africa, with the island of Madagascar reporting almost one third of human cases worldwide. In the highlands of Madagascar, plague is transmitted predominantly by two flea species which coexist on the island, but differ in their distribution. The endemic flea, Synopsyllus fonquerniei, dominates flea communities on rats caught outdoors, while the cosmopolitan flea, Xenopsylla cheopis, is found mostly on rats caught in houses. Additionally S. fonquerniei seems restricted to areas above 800 m. Climatic constraints on the development of the two main vectors of plague could explain the differences in their distribution and the seasonal changes in their abundance. Here we present the first study on effects of temperature and relative humidity on the immature stages of both vector species. We examined the two species' temperature and humidity requirements under experimental conditions at five different temperatures and two relative humidities. By employing multivariate and survival analysis we established the impact of temperature and relative humidity on development times and survival for both species. Using degree-day analysis we then predicted the average developmental threshold for larvae to reach pupation and for pupae to complete development under each treatment. This analysis was undertaken separately for the two relative humidities and for the two species. Development times and time to death differed significantly, with the endemic S. fonquerniei taking on average 1.79 times longer to complete development and having a shorter time to death than X. cheopis under adverse conditions with high temperature and low humidity. Temperature had a significant effect on the development times of flea larvae and pupae. While humidity did not affect the development times of either species, it did influence the time of death of S. fonquerniei. Using degree-day analysis we estimated an

  1. Impact of initial time to prostate-specific antigen nadir on survival in prostate cancer with bone metastasis initially treated with maximum androgen blockade therapy

    Directory of Open Access Journals (Sweden)

    Yamamoto Y

    2013-10-01

    Full Text Available Background: The objective of this study is to provide certain data on clinical outcomes and their predictors of traditional maximum androgen blockade (MAB in prostate cancer with bone metastasis. Methods: Subjects were patients with prostate adenocarcinoma with bone metastasis initiated to treat with MAB as a primary treatment without any local therapy at our hospital between January 2003 and December 2010. Time to prostate specific antigen (PSA progression, overall survival (OS time, and association of clinical factors and outcomes were retrospectively evaluated. Results: A total of 57 patients were evaluable. The median age was 70 years. The median primary PSA was 203 ng/ml. Luteinizing hormone-releasing hormone agonists had been administered in 96.5% of the patients. Bicalutamide had been chosen in 89.4 % of the patients as the initial antiandrogen. The median time to PSA progression with MAB was 11.3 months (95% confidence interval [CI], 10.4 to 13.0. The median OS was 47.3 months (95% CI, 30.7 to 81.0. Gleason score 9 or greater, decline of PSA level equal to or higher than 1.0 ng/ml with MAB, and time to PSA nadir equal to or shorter than six months after initiation of MAB were independent risk factors for time to PSA progression (P=0.010, P=0.005, and P=0.001; respectively. Time to PSA nadir longer than six months was the only independent predictor for longer OS (HR, 0.255 [95% CI, 0.109 to 0.597]; P=0.002. Conclusions: Initial time to PSA nadir should be emphasized for clinical outcome analyses in future studies on prostate cancer with bone metastasis.

  2. DCE-MRI prediction of survival time for patients with glioblastoma multiforme: using an adaptive neuro-fuzzy-based model and nested model selection technique.

    Science.gov (United States)

    Dehkordi, Azimeh N V; Kamali-Asl, Alireza; Wen, Ning; Mikkelsen, Tom; Chetty, Indrin J; Bagher-Ebadian, Hassan

    2017-09-01

    This pilot study investigates the construction of an Adaptive Neuro-Fuzzy Inference System (ANFIS) for the prediction of the survival time of patients with glioblastoma multiforme (GBM). ANFIS is trained by the pharmacokinetic (PK) parameters estimated by the model selection (MS) technique in dynamic contrast enhanced-magnetic resonance imaging (DCE-MRI) data analysis, and patient age. DCE-MRI investigations of 33 treatment-naïve patients with GBM were studied. Using the modified Tofts model and MS technique, the following physiologically nested models were constructed: Model 1, no vascular leakage (normal tissue); Model 2, leakage without efflux; Model 3, leakage with bidirectional exchange (influx and efflux). For each patient, the PK parameters of the three models were estimated as follows: blood plasma volume (vp ) for Model 1; vp and volume transfer constant (K(trans) ) for Model 2; vp , K(trans) and rate constant (kep ) for Model 3. Using Cox regression analysis, the best combination of the estimated PK parameters, together with patient age, was identified for the design and training of ANFIS. A K-fold cross-validation (K = 33) technique was employed for training, testing and optimization of ANFIS. Given the survival time distribution, three classes of survival were determined and a confusion matrix for the correct classification fraction (CCF) of the trained ANFIS was estimated as an accuracy index of ANFIS's performance. Patient age, kep and ve (K(trans) /kep ) of Model 3, and K(trans) of Model 2, were found to be the most effective parameters for training ANFIS. The CCF of the trained ANFIS was 84.8%. High diagonal elements of the confusion matrix (81.8%, 90.1% and 81.8% for Class 1, Class 2 and Class 3, respectively), with low off-diagonal elements, strongly confirmed the robustness and high performance of the trained ANFIS for predicting the three survival classes. This study confirms that DCE-MRI PK analysis, combined with the MS technique and ANFIS

  3. Improvement of recurrence-free survival after radical prostatectomy for locally advanced prostate cancer in relation to the time of surgical intervention

    Directory of Open Access Journals (Sweden)

    E. I. Veliev

    2016-01-01

    Full Text Available Objective: to comparatively estimate the frequency of a positive surgical margin and 5-year biochemical recurrent-free survival (BRFS rates in patients with locally advanced prostate cancer in relation to the time of radical retropubic prostatectomy.Subjects and methods. The investigation enrolled 274 patients with prostate cancer (pT3-4N0-1M0 who were divided into 2 groups of 68 and 20 patients operated on in 1997 to 2006 and 2007 to 2012, respectively. Two surgeons made surgical interventions by the standardized procedure. The 5-year BRFS rates were estimated using the Kaplan-Meier method and log-rank test. A biochemical recurrence was defined as a prostatespecific antigen level of t 0.2 ng / ml in 2 consecutive measurements or as the initiation of adjuvant therapy.Results. The detection rate of a positive surgical margin decreased from 55.9 % in 1997–2006 to 37.9 % in 2007–2012 (p = 0.01; the 5-year recurrence-free survival rates were 38.8 % versus 66.2 % (p < 0.001.Conclusion. These changes would probably be a result of surgeons» better experience and improved surgical techniques in the course of time.

  4. Effect of fish oil, arginine, and doxorubicin chemotherapy on remission and survival time for dogs with lymphoma: a double-blind, randomized placebo-controlled study.

    Science.gov (United States)

    Ogilvie, G K; Fettman, M J; Mallinckrodt, C H; Walton, J A; Hansen, R A; Davenport, D J; Gross, K L; Richardson, K L; Rogers, Q; Hand, M S

    2000-04-15

    Polyunsaturated n-3 fatty acids have been shown to inhibit the growth and metastasis of tumors. This double-blind, randomized study was designed to evaluate the hypothesis that polyunsaturated n-3 fatty acids can improve metabolic parameters, decrease chemical indices of inflammation, enhance quality of life, and extend disease free interval and survival time for dogs treated for lymphoblastic lymphoma with doxorubicin chemotherapy. Thirty-two dogs with lymphoma were randomized to receive one of two diets supplemented with menhaden fish oil and arginine (experimental diet) or an otherwise identical diet supplemented with soybean oil (control diet). Diets were fed before and after remission was attained with up to five dosages of doxorubicin. Parameters examined included blood concentrations of glucose, lactic acid, and insulin in response to glucose and diet tolerance tests; alpha-1 acid glycoprotein; tumor necrosis factor; interleukin-6; body weight; amino acid profiles; resting energy expenditure; disease free interval (DFI); survival time (ST); and clinical performance scores. Dogs fed the experimental diet had significantly (P diet tolerance testing. Increasing C22:6 levels were significantly (P dogs with Stage III lymphoma fed the experimental diet. Fatty acids of the n-3 series normalize elevated blood lactic acid in a dose-dependent manner, resulting in an increase in DFI and ST for dogs with lymphoma. Copyright 2000 American Cancer Society.

  5. Effects of Oral Administration of Fucoidan Extracted from Cladosiphon okamuranus on Tumor Growth and Survival Time in a Tumor-Bearing Mouse Model

    Directory of Open Access Journals (Sweden)

    Yoshiharu Okamoto

    2012-10-01

    Full Text Available We evaluated the anti-tumor activities of the oral administration of fucoidan extracted from Cladosiphon okamuranus using a tumor (colon 26-bearing mouse model. The materials used included low-molecular-weight fucoidan (LMWF: 6.5–40 kDa, intermediate-molecular-weight fucoidan (IMWF: 110–138 kDa and high-molecular-weight fucoidan (HMWF: 300–330 kDa. The IMWF group showed significantly suppressed tumor growth. The LMWF and HMWF groups showed significantly increased survival times compared with that observed in the control group (mice fed a fucoidan-free diet. The median survival times in the control, LMWF, IMWF and HMWF groups were 23, 46, 40 and 43 days, respectively. It was also found that oral administration of fucoidan increased the population of natural killer cells in the spleen. Furthermore, from the results of the experiment using Myd-88 knockout mice, it was found that these effects are related to gut immunity. These results suggest that fucoidan is a candidate anti-tumor functional food.

  6. N-Acetylaspartate Synthase Deficiency Corrects the Myelin Phenotype in a Canavan Disease Mouse Model But Does Not Affect Survival Time.

    Science.gov (United States)

    Maier, Helena; Wang-Eckhardt, Lihua; Hartmann, Dieter; Gieselmann, Volkmar; Eckhardt, Matthias

    2015-10-28

    Canavan disease (CD) is a severe, lethal leukodystrophy caused by deficiency in aspartoacylase (ASPA), which hydrolyzes N-acetylaspartate (NAA). In the brains of CD patients, NAA accumulates to high millimolar concentrations. The pathology of the disease is characterized by loss of oligodendrocytes and spongy myelin degeneration in the CNS. Whether accumulating NAA, absence of NAA-derived acetate, or absence of any unknown functions of the ASPA enzyme is responsible for the pathology of the disease is not fully understood. We generated ASPA-deficient (Aspa(nur7/nur7)) mice that are also deficient for NAA synthase Nat8L (Nat8L(-/-)/Aspa(nur7/nur7)). These mice have no detectable NAA. Nevertheless, they exhibited normal myelin content, myelin sphingolipid composition, and full reversal of spongy myelin and axonal degeneration. Surprisingly, although pathology was fully reversed, the survival time of the mice was not prolonged. In contrast, Aspa(nur7/nur7) mice with only one intact Nat8L allele accumulated less NAA, developed a less severe pathology, phenotypic improvements, and, importantly, an almost normal survival time. Therefore, inhibition of NAA synthase is a promising therapeutic option for CD. The reduced survival rate of Nat8L(-/-)/Aspa(nur7/nur7) mice, however, indicates that complete inhibition of NAA synthase may bear unforeseeable risks for the patient. Furthermore, we demonstrate that acetate derived from NAA is not essential for myelin lipid synthesis and that loss of NAA-derived acetate does not cause the myelin phenotype of Aspa(nur7/nur7) mice. Our data clearly support the hypothesis that NAA accumulation is the major factor in the development of CD. Copyright © 2015 the authors 0270-6474/15/3514501-16$15.00/0.

  7. Influence of tumour stage at breast cancer detection on survival in modern times: population based study in 173,797 patients.

    Science.gov (United States)

    Saadatmand, Sepideh; Bretveld, Reini; Siesling, Sabine; Tilanus-Linthorst, Madeleine M A

    2015-10-06

    To assess the influence of stage at breast cancer diagnosis, tumour biology, and treatment on survival in contemporary times of better (neo-)adjuvant systemic therapy. Prospective nationwide population based study. Nationwide Netherlands Cancer Registry. Female patients with primary breast cancer diagnosed between 1999 and 2012 (n=173,797), subdivided into two time cohorts on the basis of breast cancer diagnosis: 1999-2005 (n=80,228) and 2006-12 (n=93,569). Relative survival was compared between the two cohorts. Influence of traditional prognostic factors on overall mortality was analysed with Cox regression for each cohort separately. Compared with 1999-2005, patients from 2006-12 had smaller (≤ T1 65% (n=60,570) v 60% (n=48,031); Page and tumour type, overall mortality was decreased by surgery (especially breast conserving), radiotherapy, and systemic therapies. Mortality increased with progressing tumour size in both cohorts (2006-12 T1c v T1a: hazard ratio 1.54, 95% confidence interval 1.33 to 1.78), but without a significant difference in invasive breast cancers until 1 cm (2006-12 T1b v T1a: hazard ratio 1.04, 0.88 to 1.22), and independently with progressing number of positive lymph nodes (2006-12 N1 v N0: 1.25, 1.17 to 1.32). Tumour stage at diagnosis of breast cancer still influences overall survival significantly in the current era of effective systemic therapy. Diagnosis of breast cancer at an early tumour stage remains vital. © Saadatmand et al 2015.

  8. Modeling association between times to recurrence of the different polarities in bipolar disorder among service seekers in urban Nigeria: a survival analysis approach

    Directory of Open Access Journals (Sweden)

    Fagbamigbe AF

    2017-07-01

    Full Text Available Adeniyi Francis Fagbamigbe,1 Victor Adesola Makanjuola2 1Department of Epidemiology and Medical Statistics, Faculty of Public Health, College of Medicine, University of Ibadan, Nigeria; 2Department of Psychiatry, College of Medicine, University of Ibadan, Ibadan Nigeria Introduction: Bipolar disorder (BD remains both a clinical and public health challenge worldwide, especially in developing countries such as Nigeria. Many studies have focused on prevalence and recurrences among BD service seekers but little has been documented on the nature, strength, direction, existence, and estimation of association between times to recurrence of the two possible polarities or mood episodes in BD. In this study, we explored the association between durations before recurrence of depression and manic episodes among people seeking treatment for BD.Methods: This analytical study used retrospective data of 467 persons who sought treatment for BD at the psychiatric clinic of University College Hospital, Ibadan, Nigeria between 2005 and 2014. Descriptive statistics were used to explore the data. We right-censored the data and obtained Kaplan–Meier estimates of the time to recurrence of the outcomes and transformed the estimates to standardized binormal data using quantile-quantile transformation. The likelihood was maximized to obtain the maximum likelihood estimate of the association parameter at 5% significance level.Results: The mean (± standard deviation age of the respondents was 32.9±12.9 years, this was lower among service seekers who were initially diagnosed with mania than among those initially diagnosed with depression (31.3±11.6, 33.2±11.9, respectively. The median survival time to recurrence of mania and depression among the patients was 1,120 and 745 days, respectively, whereas association between times to recurrence of mania and depression was maximized at 0.67 (95% confidence interval: 0.62–0.71.Conclusion: There exists a strong and positive

  9. The Effect of Platelet-Rich Plasma on Survival of the Composite Graft and the Proper Time of Injection in a Rabbit Ear Composite Graft Model

    Directory of Open Access Journals (Sweden)

    Hyun Nam Choi

    2014-11-01

    Full Text Available BackgroundAdministration of growth factors has been associated with increased viability of composite grafts greater than 1-cm in diameter. Platelet-rich plasma (PRP contains many of the growth factors studied. In this study, we evaluate the effect of PRP injection on composite graft viability and the proper time for injection.MethodsA total of 24 New Zealand White rabbits were divided into four groups. Autologous PRP was injected into the recipient sites three days before grafting in group 1, on the day of grafting in group 2, and three days after grafting in group 3. Group 4 served as control without PRP administration. Auricular composite grafts of 3-cm diameter were harvested and grafted back into place after being rotated 180 degrees. Median graft viability and microvessel density were evaluated at day 21 of graft via macroscopic photographs and immunofluorescent staining, respectively.ResultsThe median graft survival rate was 97.8% in group 1, 69.2% in group 2, 55.7% in group 3, and 40.8% in the control group. The median vessel counts were 34 (per ×200 HPF in group 1, 24.5 in group 2, 19.5 in group 3, and 10.5 in the control group.ConclusionsThis study demonstrates that PRP administration is associated with increased composite graft viability. All experimental groups showed a significantly higher survival rate and microvessel density, compared with the control group. Pre-administration of PRP was followed by the highest graft survival rate and revascularization. PRP treatments are minimally invasive, fast, easily applicable, and inexpensive, and offer a potential clinical pathway to larger composite grafts.

  10. Nuclear morphometry in histological specimens of canine prostate cancer: Correlation with histological subtypes, Gleason score, methods of collection and survival time.

    Science.gov (United States)

    Di Donato, Guido; Laufer-Amorim, Renée; Palmieri, Chiara

    2017-10-01

    Ten normal prostates, 22 benign prostatic hyperplasia (BPH) and 29 prostate cancer (PC) were morphometrically analyzed with regard to mean nuclear area (MNA), mean nuclear perimeter (MNP), mean nuclear diameter (MND), coefficient of variation of the nuclear area (NACV), mean nuclear diameter maximum (MDx), mean nuclear diameter minimum (MDm), mean nuclear form ellipse (MNFe) and form factor (FF). The relationship between nuclear morphometric parameters and histological type, Gleason score, methods of sample collection, presence of metastases and survival time of canine PC were also investigated. Overall, nuclei from neoplastic cells were larger, with greater variation in nuclear size and shape compared to normal and hyperplastic cells. Significant differences were found between more (small acinar/ductal) and less (cribriform, solid) differentiated PCs with regard to FF (pnuclear morphometric analysis in combination with Gleason score can help in canine prostate cancer grading, thus contributing to the establishment of a more precise prognosis and patient's management. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Methodology for lognormal modelling of malignant pleural mesothelioma survival time distributions: a study of 5580 case histories from Europe and USA

    Energy Technology Data Exchange (ETDEWEB)

    Mould, Richard F [41 Ewhurst Avenue, South Croydon, Surrey CR2 0DH (United Kingdom); Lahanas, Michael [Klinikum Offenbach, Strahlenklinik, 66 Starkenburgring, 63069 Offenbach am Main (Germany); Asselain, Bernard [Institut Curie, Biostatistiques, 26 rue d' Ulm, 75231 Paris Cedex 05 (France); Brewster, David [Director, Scottish Cancer Registry, Information Services (NHS National Services Scotland) Area 155, Gyle Square, 1 South Gyle Crescent, Edinburgh EH12 9EB (United Kingdom); Burgers, Sjaak A [Department of Thoracic Oncology, Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam, The (Netherlands); Damhuis, Ronald A M [Rotterdam Cancer Registry, Rochussenstraat 125, PO Box 289, 3000 AG Rotterdam, The (Netherlands); Rycke, Yann De [Institut Curie, Biostatistiques, 26 rue d' Ulm, 75231 Paris Cedex 05 (France); Gennaro, Valerio [Liguria Mesothelioma Cancer Registry, Etiology and Epidemiology Department, National Cancer Research Institute, Pad. Maragliano, Largo R Benzi, 10-16132 Genoa (Italy); Szeszenia-Dabrowska, Neonila [Department of Occupational and Environmental Epidemiology, National Institute of Occupational Medicine, PO Box 199, Swietej Teresy od Dzieciatka Jezus 8, 91-348 Lodz (Poland)

    2004-09-07

    A truncated left-censored and right-censored lognormal model has been validated for representing pleural mesothelioma survival times in the range 5-200 weeks for data subsets grouped by age for males, 40-49, 50-59, 60-69, 70-79 and 80+ years and for all ages combined for females. The cases available for study were from Europe and USA and totalled 5580. This is larger than any other pleural mesothelioma cohort accrued for study. The methodology describes the computation of reference baseline probabilities, 5-200 weeks, which can be used in clinical trials to assess results of future promising treatment methods. This study is an extension of previous lognormal modelling by Mould et al (2002 Phys. Med. Biol. 47 3893-924) to predict long-term cancer survival from short-term data where the proportion cured is denoted by C and the uncured proportion, which can be represented by a lognormal, by (1 - C). Pleural mesothelioma is a special case when C = 0.

  12. Extension of the biotic ligand model of acute toxicity to a physiologically-based model of the survival time of rainbow trout (Oncorhynchus mykiss) exposed to silver.

    Science.gov (United States)

    Paquin, Paul R; Zoltay, Viktoria; Winfield, Richard P; Wu, Kuen Benjamin; Mathew, Rooni; Santore, Robert C; Di Toro, Dominic M

    2002-09-01

    Chemical speciation controls the bioavailability and toxicity of metals in aquatic systems and regulatory agencies are recognizing this as they develop updated water quality criteria (WQC) for metals. The factors that affect bioavailability may be quantitatively evaluated with the biotic ligand model (BLM). Within the context of the BLM framework, the 'biotic ligand' is the site where metal binding results in the manifestation of a toxic effect. While the BLM does account for the speciation and complexation of dissolved metal in solution, and competition among the free metal ion and other cations for binding sites at the biotic ligand, it does not explicitly consider either the physiological effects of metals on aquatic organisms, or the direct effect of water chemistry parameters such as pH, Ca(2+)and Na(+) on the physiological state of the organism. Here, a physiologically-based model of survival time is described. In addition to incorporating the effects of water chemistry on metal availability to the organism, via the BLM, it also considers the interaction of water chemistry on the physiological condition of the organism, independent of its effect on metal availability. At the same time it explicitly considers the degree of interaction of these factors with the organism and how this affects the rate at which cumulative damage occurs. An example application of the model to toxicity data for rainbow trout exposed to silver is presented to illustrate how this framework may be used to predict survival time for alternative exposure durations. The sodium balance model (SBM) that is described herein, a specific application of a more generic ion balance model (IBM) framework, adds a new physiological dimension to the previously developed BLM. As such it also necessarily adds another layer of complexity to this already useful predictive framework. While the demonstrated capability of the SBM to predict effects in relation to exposure duration is a useful feature of this

  13. Estimation of the probability of bacterial population survival: Development of a probability model to describe the variability in time to inactivation of Salmonella enterica.

    Science.gov (United States)

    Koyama, Kento; Hokunan, Hidekazu; Hasegawa, Mayumi; Kawamura, Shuso; Koseki, Shigenobu

    2017-12-01

    Despite the development of numerous predictive microbial inactivation models, a model focusing on the variability in time to inactivation for a bacterial population has not been developed. Additionally, an appropriate estimation of the risk of there being any remaining bacterial survivors in foods after the application of an inactivation treatment has not yet been established. Here, Gamma distribution, as a representative probability distribution, was used to estimate the variability in time to inactivation for a bacterial population. Salmonella enterica serotype Typhimurium was evaluated for survival in a low relative humidity environment. We prepared bacterial cells with an initial concentration that was adjusted to 2 × 10n colony-forming units/2 μl (n = 1, 2, 3, 4, 5) by performing a serial 10-fold dilution, and then we placed 2 μl of the inocula into each well of 96-well microplates. The microplates were stored in a desiccated environment at 10-20% relative humidity at 5, 15, or 25 °C. The survival or death of bacterial cells for each well in the 96-well microplate was confirmed by adding tryptic soy broth as an enrichment culture. The changes in the death probability of the 96 replicated bacterial populations were described as a cumulative Gamma distribution. The variability in time to inactivation was described by transforming the cumulative Gamma distribution into a Gamma distribution. We further examined the bacterial inactivation on almond kernels and radish sprout seeds. Additionally, we described certainty levels of bacterial inactivation that ensure the death probability of a bacterial population at six decimal reduction levels, ranging from 90 to 99.9999%. Consequently, the probability model developed in the present study enables us to estimate the death probability of bacterial populations in a desiccated environment over time. This probability model may be useful for risk assessment to estimate the amount of remaining bacteria in a given

  14. Timing of Whole Brain Radiotherapy on Survival of Patients with EGFR-mutated 
Non-small Cell Lung Cancer and Brain Metastases

    Directory of Open Access Journals (Sweden)

    Guimei LIU

    2016-08-01

    Full Text Available Background and objective There is no high-level evidence for the time of whole brain radiotherapy (WBRT for patients with epidermal growth factor receptor (EGFR-mutated non-small cell lung cancer (NSCLC and brain metastases. The aim of this study is to assess the appropriate timing of WBRT for patients with EGFR-mutated NSCLC and brain metastases (BM. Methods There were 78 patients diagnosed with EGFR-mutated NSCLC and BM in Beijing Chest Hospital between August 2009 and May 2015. 48 untreated patients who received both WBRT and EGFR-tyrosine kinase inhibitors (TKIs therapy. Prognostic factors of intracranial progression-free survival (PFS and overall survival (OS were identified by Cox proportional hazards modeling. Results Intracranial objective response rate was 81.3% and disease control rate was 93.8%. Median intracranial PFS was 10 months. Median OS was 18 months. Multivariate analysis of intracranial PFS revealed that Eastern Cooperative Oncology Group (ECOG performance status (PS 0-1 (HR=30.436, 95%CI: 4.721-196.211, P<0.001 and early WBRT (HR=3.663, 95%CI: 1.657-8.098, P=0.001 had a better intracranial PFS. Multivariate analysis of OS revealed that PS 0-1 (HR=57.607, 95%CI: 6.135-540.953, P<0.001, early WBRT (HR=2.757, 95%CI: 1.140-6.669, P=0.024, and stereotactic radiosurgery (HR=5.964, 95%CI: 1.895-18.767, P=0.002 were independent prognostic factors of OS. Conclusion Early WBRT combined with EGFR-TKIs can improve outcomes of patients with EGFR-mutated NSCLC and BM, but it needs to be confirmed by large-sample-size and multicenter prospective clinical trials.

  15. Exploration for unknown substances in rapeseed oil that shorten survival time of stroke-prone spontaneously hypertensive rats. Effects of super critical gas extraction fractions.

    Science.gov (United States)

    Ohara, Naoki; Naito, Yukiko; Nagata, Tomoko; Tatematsu, Kenjiro; Fuma, Shin-Ya; Tachibana, Shigehiro; Okuyama, Harumi

    2006-07-01

    To identify the causative substances for the shortening of survival time by rapeseed (Canola) oil in stroke-prone spontaneously hypertensive rats (SHRSP), SHRSP were fed on a standard chow supplemented with 10 w/w% soybean oil (control), rapeseed oil, one of the fractions of rapeseed oil obtained by super critical gas extraction (SCE) under a pressure of 180-bar or 350-bar, at 40 degrees C, or the residue from the extraction (with 0.5% NaCl in drinking water). In another series of experiment, SHRSP were fed for 8 weeks on the above-mentioned diets without salt loading and autopsied. Fatty acid compositions in these diets were similar, except in the soybean oil diet, and phytosterol contents were: (diet containing) 180-bar fraction>residue>rapeseed oil>350-bar fraction>soybean oil. Survival times in the rapeseed oil, 350-bar fraction and residue groups were shorter than, whereas that in the 180-bar fraction was similar to in the soybean oil group. In the 8-week feeding experiment, chronic nephropathy was found frequently in the groups other than the soybean oil group. The heart weights were higher in the rapeseed oil and residue groups. Cerebral necrosis was found in the residue group. Taken together, the followings are concluded, (1) Neither the fatty acid composition, nor the amount of phytosterols in the diets appeared to be decisive in the shortening of life. (2) SCE appeared to produce a safe (180-bar) fraction, though it failed to separate clearly the causative substances into specific fractions. (3) The factors that facilitate the genetic disease of SHRSP appear to exist in rapeseed oil. However, they might not be identical to those responsible for the life-shortening, since there were no findings common across the rapeseed oil, 350-bar and residue groups, which showed similar life-shortening.

  16. Role functioning before start of adjuvant treatment was an independent prognostic factor for survival and time to failure. A report from the Nordic adjuvant interferon trial for patients with high-risk melanoma

    DEFF Research Database (Denmark)

    Brandberg, Yvonne; Johansson, Hemming; Aamdal, Steinar

    2013-01-01

    To investigate the role of health-related quality of life (HRQoL) at randomization as independent prognostic factors for survival and time to failure, and to explore associations between HRQoL and treatment effects....

  17. Real-time systems

    OpenAIRE

    Badr, Salah M.; Bruztman, Donald P.; Nelson, Michael L.; Byrnes, Ronald Benton

    1992-01-01

    This paper presents an introduction to the basic issues involved in real-time systems. Both real-time operating sys and real-time programming languages are explored. Concurrent programming and process synchronization and communication are also discussed. The real-time requirements of the Naval Postgraduate School Autonomous Under Vehicle (AUV) are then examined. Autonomous underwater vehicle (AUV), hard real-time system, real-time operating system, real-time programming language, real-time sy...

  18. The Transcriptional Response of Neurotrophins and Their Tyrosine Kinase Receptors in Lumbar Sensorimotor Circuits to Spinal Cord Contusion is Affected by Injury Severity and Survival Time

    Science.gov (United States)

    Hougland, M. Tyler; Harrison, Benjamin J.; Magnuson, David S. K.; Rouchka, Eric C.; Petruska, Jeffrey C.

    2013-01-01

    Traumatic spinal cord injury (SCI) results in changes to the anatomical, neurochemical, and physiological properties of cells in the central and peripheral nervous system. Neurotrophins, acting by binding to their cognate Trk receptors on target cell membranes, contribute to modulation of anatomical, neurochemical, and physiological properties of neurons in sensorimotor circuits in both the intact and injured spinal cord. Neurotrophin signaling is associated with many post-SCI changes including maladaptive plasticity leading to pain and autonomic dysreflexia, but also therapeutic approaches such as training-induced locomotor improvement. Here we characterize expression of mRNA for neurotrophins and Trk receptors in lumbar dorsal root ganglia (DRG) and spinal cord after two different severities of mid-thoracic injury and at 6 and 12 weeks post-SCI. There was complex regulation that differed with tissue, injury severity, and survival time, including reversals of regulation between 6 and 12 weeks, and the data suggest that natural regulation of neurotrophins in the spinal cord may continue for months after birth. Our assessments determined that a coordination of gene expression emerged at the 12-week post-SCI time point and bioinformatic analyses address possible mechanisms. These data can inform studies meant to determine the role of the neurotrophin signaling system in post-SCI function and plasticity, and studies using this signaling system as a therapeutic approach. PMID:23316162

  19. Evaluating Distributed Timing Constraints

    DEFF Research Database (Denmark)

    Kristensen, C.H.; Drejer, N.

    1994-01-01

    In this paper we describe a solution to the problem of implementing time-optimal evaluation of timing constraints in distributed real-time systems.......In this paper we describe a solution to the problem of implementing time-optimal evaluation of timing constraints in distributed real-time systems....

  20. Choosing between his time and her time?

    DEFF Research Database (Denmark)

    Deding, Mette; Lausten, Mette

    When adding up market work and non-market work, Danish men and women work about the same number of hours per day. While men do the major share of the market work, women do the major share of the non-market work. In this paper, we investigate the interaction between the different time use activities...... for Danish working couples. The analysis is based on the Danish Time Use Survey from 2001, which contains detailed time use information for both spouses. We analyse the time used by each spouse on market work and non-market work, taking the endogeneity of time regressors into account. Non-market work...... consists of both ordinary housework and childcare. We analyse whether these two activities are structurally different by estimating them separately and find strong evidence in favour of this hypothesis. Results show that substitution between time use activities is found both for individuals and between...

  1. Effect of growth on the thermal resistance and survival of Salmonella Tennessee and Oranienburg in peanut butter, measured by a new thin-layer thermal death time device.

    Science.gov (United States)

    Keller, Susanne E; Grasso, Elizabeth M; Halik, Lindsay A; Fleischman, Gregory J; Chirtel, Stuart J; Grove, Stephen F

    2012-06-01

    In published data the thermal destruction of Salmonella species in peanut butter deviates from pseudo-first-order kinetics. The reasons for such deviation are unknown. This study examined both the method used to measure the thermal destruction rate and the method of growth of the microorganisms to explain variations in destruction kinetics. Growth on a solid matrix results in a different physiological state that may provide greater resistance to adverse environments. In this study, Salmonella Tennessee and Oranienburg were grown for 24 h at 37°C under aerobic conditions in broth and agar media to represent planktonic and sessile cell growth, respectively. Peanut butter was held at 25°C and tested for Salmonella levels immediately after inoculation and at various time intervals up to 2 weeks. Thermal resistance was measured at 85°C by use of a newly developed thin-layer metal sample holder. Although thermal heat transfer through the metal device resulted in longer tau values than those obtained with plastic bags (32.5 ± 0.9 versus 12.4 ± 1.9 s), the bags have a relative variability of about 15 % compared with about 3 % in the plates, allowing improved uniformity of sample treatment. The two serovars tested in the thin-layer device showed similar overall thermal resistance levels in peanut butter regardless of growth in sessile or planktonic states. However, thermal destruction curves from sessile cultures exhibited greater linearity than those obtained from planktonic cells (P = 0.0198 and 0.0047 for Salmonella Oranienburg and Salmonella Tennessee, respectively). In addition, both Salmonella serovars showed significantly higher survival in peanut butter at 25°C when originally grown on solid media (P = 0.001) with a survival of Salmonella at different temperatures in a low-water-activity environment such as peanut butter.

  2. Shackle in time - time in Shackle

    DEFF Research Database (Denmark)

    Madsen, Mogens Ove

    2015-01-01

    GLS Shackle got much and the crucial inspiration from John Maynard Keynes. But that's not all. He took a number of further consequences of Keynes’ thoughts. This implies for example ideal claims to economists - having to deal with both mechanical time and expectational time. In consequence the idea...

  3. Time crystals: a review

    Science.gov (United States)

    Sacha, Krzysztof; Zakrzewski, Jakub

    2018-01-01

    Time crystals are time-periodic self-organized structures postulated by Frank Wilczek in 2012. While the original concept was strongly criticized, it stimulated at the same time an intensive research leading to propositions and experimental verifications of discrete (or Floquet) time crystals—the structures that appear in the time domain due to spontaneous breaking of discrete time translation symmetry. The struggle to observe discrete time crystals is reviewed here together with propositions that generalize this concept introducing condensed matter like physics in the time domain. We shall also revisit the original Wilczek’s idea and review strategies aimed at spontaneous breaking of continuous time translation symmetry.

  4. Time in antiquity

    CERN Document Server

    Hannah, Robert

    2008-01-01

    Time in Antiquity explores the different perceptions of time from Classical antiquity, principally through the technology designed to measure, mark or tell time. The material discussed ranges from the sixth century BC in archaic Greece to the 3rd century AD in the Roman Empire, and offers fascinating insights into ordinary people's perceptions of time and time-keeping instruments.

  5. Reaction Time (Polish language)

    OpenAIRE

    Iermakov, Sergii

    2014-01-01

    Reaction time is the interval time between the presentation of a stimulus and the initiation of the muscular response to that stimulus.If there is only one possible response (simple reaction time) it will only take a short time to react. If there are several possible responses (choice reaction time) then it will take longer to determine which response to carry out.

  6. Screen time and children

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000355.htm Screen time and children To use the sharing features on ... videos is considered unhealthy screen time. Current Screen Time Guidelines Children under age 2 should have no ...

  7. Continuous-time signals

    CERN Document Server

    Shmaliy, Yuriy

    2006-01-01

    Gives a modern description of continuous-time deterministic signals Signal formation techniquesTime vs. frequency and frequency vs. time analysisCorrelation and energy analysisNarrowband signals and sampling.

  8. Time-frequency / time-scale analysis

    CERN Document Server

    Flandrin, Patrick

    1999-01-01

    This highly acclaimed work has so far been available only in French. It is a detailed survey of a variety of techniques for time-frequency/time-scale analysis (the essence of "Wavelet Analysis"). This book has broad and comprehensive coverage of a topic of keen interest to a variety of engineers, especially those concerned with signal and image processing. Flandrin provides a discussion of numerous issues and problems that arise from a mixed description in time and frequency, as well as problems in interpretation inherent in signal theory. Key Features * Detailed coverage of both linear and quadratic solutions * Various techniques for both random and deterministic signals.

  9. Out of Time: Maternal time and disability

    Directory of Open Access Journals (Sweden)

    Rachel Robertson

    2015-01-01

    Full Text Available Starting from a maternal experience of temporal dissonance, this article takes a feminist disability studies approach to exploring disabled maternal temporality. After establishing how notions of time are central to discourses about disability and summarising some key discussions on women's time and caring, I use Lisa Baraitser's work on interrupted time and mothering to develop a parallel between the way both maternal and disabled subjectivities problematise temporality. My discussion then draws on Alison Kafer's and Rosemarie Garland-Thomson's discussions about futurity to explore the relationship between futurity, maternal subjectivity and disability, arguing for the ethical value of the maternal experience.

  10. Variations of motility and survival with storage time at 4°C of epididymal spermatozoa Ouled-Djellal breed rams in Eastern Algeria.

    Science.gov (United States)

    Safsaf, B; Belkadi, S; Belkacem, L; Mamache, B; Tlidjane, M

    2015-03-01

    The aim of this study was to evaluate some reproduction performances in Ouled-Djellal rams. This study involved genital organs removed after slaughter from 54 rams at the municipal slaughterhouse of Batna (East Algeria). The measurements of survival and mobility of epididymal sperm followed at 0, 24, 48 and 72 h after collection, revealed significant (p0.001) according to time. Thus, concerning the sperm motility the values were 91.00±2.40%, 89.20±2.40%, 77.00±6.20% and 62.60±1.20% at 0, 24, 48 and 72 h, respectively. Indeed, in live sperm, the viability rates were 82.15±1.48%, 77.67±1.74%, 66.56±1.95% and 52.30±1.46% at 0, 24, 48 and 72 h, respectively. This study revealed that epididymal spermatozoa stored at 04°C for 72 h kept their mobility and vitality at nearly a half of their the original parameters.

  11. Variations of motility and survival with storage time at 4°C of epididymal spermatozoa Ouled-Djellal breed rams in Eastern Algeria

    Directory of Open Access Journals (Sweden)

    B. Safsaf

    2015-03-01

    Full Text Available Aim: The aim of this study was to evaluate some reproduction performances in Ouled-Djellal rams. Materials and Methods: This study involved genital organs removed after slaughter from 54 rams at the municipal slaughterhouse of Batna (East Algeria. Results: The measurements of survival and mobility of epididymal sperm followed at 0, 24, 48 and 72 h after collection, revealed significant (p0.001 according to time. Thus, concerning the sperm motility the values were 91.00±2.40%, 89.20±2.40%, 77.00±6.20% and 62.60±1.20% at 0, 24, 48 and 72 h, respectively. Indeed, in live sperm, the viability rates were 82.15±1.48%, 77.67±1.74%, 66.56±1.95% and 52.30±1.46 at 0, 24, 48 and 72 h, respectively. Conclusion: This study revealed that epididymal spermatozoa stored at 04°C for 72 h kept their mobility and vitality at nearly a half of their the original parameters.

  12. Chemical control of flowering time

    DEFF Research Database (Denmark)

    Ionescu, Irina Alexandra; Møller, Birger Lindberg; Sánchez Pérez, Raquel

    2017-01-01

    Flowering at the right time is of great importance; it secures seed production and therefore species survival and crop yield. In addition to the genetic network controlling flowering time, there are a number of much less studied metabolites and exogenously applied chemicals that may influence...... on the genetic aspects of flowering time regulation in annuals, but less so in perennials. An alternative to plant breeding approaches is to engineer flowering time chemically via the external application of flower-inducing compounds. This review discusses a variety of exogenously applied compounds used in fruit...

  13. On Time-II: Newton's Time.

    Science.gov (United States)

    Raju, C. K.

    1991-01-01

    A study of time in Newtonian physics is presented. Newton's laws of motion, falsifiability and physical theories, laws of motion and law of gravitation, and Laplace's demon are discussed. Short bibliographic sketches of Laplace and Karl Popper are included. (KR)

  14. Talk of time

    Directory of Open Access Journals (Sweden)

    Johann-Albrecht Meylahn

    2015-03-01

    Full Text Available Maybe, before we speak of time, or maybe whilst we are speaking of time, or maybe after we have spoken of time, in the various modes of time’s insistence to exist, one should give time to the talk of time. There are various different modes of time’s insistence to exist, such as quantum physics in conversation with relativity theory where time is constructed as a fourth dimension of space. Or there are the modes of time in history, religion, psychology and philosophy, and each of these modes is composed, and composes its own specific object called time, and a particular subject who understands and interprets time in that particular mode. Yet, before, whilst or after these modes of time’s insistence to exist, one should maybe give time to time’s time. Give time for the various times to articulate themselves in the various modes of existence, thereby creating both a whole plurality of differing subjects, as well as plurality of differing objects, all called ‘time’. Once time has been given time to talk its talk, to articulate itself within the various modes, it will be interrupted by the articulations of time in various modes of time still to come. These disruptions of time by time always still to come opens the door for a theological narrative – a narrative on time, but created by the coming of messianic times, interpreted in the mode of hope but also in the mode of a promise from the past.

  15. Time and Teaching

    Science.gov (United States)

    McEwan, Anna E.

    2012-01-01

    This essay invites reflection on the phenomena of time as it impacts the day-to-day life of teachers. It also explores assumptions about time and teaching in three areas: first, beliefs about the force of time and the teacher's struggle to control it; second, beliefs about the potential of time and the benefits of its passing for teachers and…

  16. Capgras' syndrome of time.

    Science.gov (United States)

    Aziz, V M; Warner, N J

    2005-01-01

    The delusion that the usual passage of time has been changed and that time has been interfered with or is repeating itself is rare. Four patients with the delusion of warped time are presented and the significance of the symptom is discussed. The perception of the passage of time and its disorders is discussed.

  17. Elementary cycles of time

    Directory of Open Access Journals (Sweden)

    Dolce Donatello

    2013-09-01

    Full Text Available Elementary particles, i.e. the basic constituents of nature, are characterized by quantum recurrences in time. The flow of time of every physical system can be therefore decomposed in elementary cycles of time. This allows us to enforce the local nature of relativistic time, yielding interesting unified descriptions of fundamental aspects of modern physics, as shown in recent publications. Every particle can be regarded as a reference clock with time resolution of the order of the Compton time particle, many orders of magnitude more accurate than the atomic clocks. Here we report basic implications about the resulting notion of time.

  18. Perceptions of Time and Long Time Intervals

    Energy Technology Data Exchange (ETDEWEB)

    Drottz-Sjoeberg, Britt-Marie [Norwegian Univ. of Science and Technology, Trondheim (Norway). Dept. of Psychology

    2006-09-15

    There are certainly many perspectives presented in the literature on time and time perception. This contribution has focused on perceptions of the time frames related to risk and danger of radiation from a planned Swedish repository for spent nuclear fuel. Respondents from two municipalities judged SSI's reviews of the entrepreneur's plans and work of high importance, and more important the closer to our time the estimate was given. Similarly were the consequences of potential leakage from a repository perceived as more serious the closer it would be to our time. Judgements of risks related to the storage of spent nuclear fuel were moderately large on the used measurement scales. Experts are experts because they have more knowledge, and in this context they underlined e.g. the importance of reviews of the radiation situation of time periods up to 100,000 years. It was of interest to note that 55% of the respondents from the municipalities did not believe that the future repository would leak radioactivity. They were much more pessimistic with respect to world politics, i.e. a new world war. However, with respect to the seriousness of the consequences given a leakage from the repository, the public group consistently gave high risk estimates, often significantly higher than those of the expert group. The underestimations of time estimates, as seen in the tasks of pinpointing historic events, provide examples of the difficulty of making estimations involving long times. Similar results showed that thinking of 'the future' most often involved about 30 years. On average, people reported memories of about 2.5 generations back in time, and emotional relationships stretching approximately 2.5 generations into the future; 94% of the responses, with respect to how many future generations one had an emotional relationship, were given in the range of 1-5 generations. Similarly, Svenson and Nilsson found the opinion that the current generations

  19. Time in quantum mechanics

    CERN Document Server

    Mayato, R; Egusquiza, I

    2002-01-01

    The treatment of time in quantum mechanics is still an important and challenging open question in the foundation of the theory. This book describes the problems, and the attempts and achievements in defining, formalizing and measuring different time quantities in quantum theory, such as the parametric (clock) time, tunneling times, decay times, dwell times, delay times, arrival times or jump times. This multiauthored book, written as an introductory guide for the non-initiated as well as a useful source of information for the expert, covers many of the open questions. A brief historical overview is to be found in the introduction. It is followed by 12 chapters devoted to conceptual and theoretical investigations as well as experimental issues in quantum-mechanical time measurements. This unique monograph should attract physicists as well as philosophers of science working in the foundations of quantum physics.

  20. Cosmology and time

    Directory of Open Access Journals (Sweden)

    Balbi Amedeo

    2013-09-01

    Full Text Available Time has always played a crucial role in cosmology. I review some of the aspects of the present cosmological model which are more directly related to time, such as: the definition of a cosmic time; the existence of typical timescales and epochs in an expanding universe; the problem of the initial singularity and the origin of time; the cosmological arrow of time.

  1. Larval food quantity affects development time, survival and adult biological traits that influence the vectorial capacity of Anopheles darlingi under laboratory conditions

    Directory of Open Access Journals (Sweden)

    Araújo Maisa

    2012-08-01

    Full Text Available Abstract Background The incidence of malaria in the Amazon is seasonal and mosquito vectorial capacity parameters, including abundance and longevity, depend on quantitative and qualitative aspects of the larval diet. Anopheles darlingi is a major malaria vector in the Amazon, representing >95% of total Anopheles population present in the Porto Velho region. Despite its importance in the transmission of the Plasmodium parasite, knowledge of the larval biology and ecology is limited. Studies regarding aspects of adult population ecology are more common than studies on larval ecology. However, in order develop effective control strategies and laboratory breeding conditions for this species, more data on the factors affecting vector biology is needed. The aim of the present study is to assess the effects of larval food quantity on the vectorial capacity of An. darling under laboratory conditions. Methods Anopheles darlingi was maintained at 28°C, 80% humidity and exposed to a daily photoperiod of 12 h. Larvae were divided into three experimental groups that were fed either a low, medium, or high food supply (based on the food amounts consumed by other species of culicids. Each experiment was replicated for six times. A cohort of adults were also exposed to each type of diet and assessed for several biological characteristics (e.g. longevity, bite frequency and survivorship, which were used to estimate the vectorial capacity of each experimental group. Results The group supplied with higher food amounts observed a reduction in development time while larval survival increased. In addition to enhanced longevity, increasing larval food quantity was positively correlated with increasing frequency of bites, longer blood meal duration and wing length, resulting in greater vectorial capacity. However, females had greater longevity than males despite having smaller wings. Conclusions Overall, several larval and adult biological traits were significantly

  2. Survival rate and expression of Heat-shock protein 70 and Frost genes after temperature stress in Drosophila melanogaster lines that are selected for recovery time from temperature coma.

    Science.gov (United States)

    Udaka, Hiroko; Ueda, Chiaki; Goto, Shin G

    2010-12-01

    In this study, we investigated the physiological mechanisms underlying temperature tolerance using Drosophila melanogaster lines with rapid, intermediate, or slow recovery from heat or chill coma that were established by artificial selection or by free recombination without selection. Specifically, we focused on the relationships among their recovery from heat or chill coma, survival after severe heat or cold, and survival enhanced by rapid cold hardening (RCH) or heat hardening. The recovery time from heat coma was not related to the survival rate after severe heat. The line with rapid recovery from chill coma showed a higher survival rate after severe cold exposure, and therefore the same mechanisms are likely to underlie these phenotypes. The recovery time from chill coma and survival rate after severe cold were unrelated to RCH-enhanced survival. We also examined the expression of two genes, Heat-shock protein 70 (Hsp70) and Frost, in these lines to understand the contribution of these stress-inducible genes to intraspecific variation in recovery from temperature coma. The line showing rapid recovery from heat coma did not exhibit higher expression of Hsp70 and Frost. In addition, Hsp70 and Frost transcription levels were not correlated with the recovery time from chill coma. Thus, Hsp70 and Frost transcriptional regulation was not involved in the intraspecific variation in recovery from temperature coma. Copyright © 2010 Elsevier Ltd. All rights reserved.

  3. Time, Self & Intertemporal Choice

    Directory of Open Access Journals (Sweden)

    Cintia eRetz Lucci

    2013-05-01

    Full Text Available Neuroscientific studies of intertemporal choice (IC have focused mainly on the neural representation of self-control mechanisms and valuation. This reflects what has been considered as the core of the IC phenomenon. The claim of this paper is that deviations from exponential reward discounting as a function of time might be fully accounted for by the deviation of subjective time from calendar time. This claim is based on evidence that specificities of time perception can modulate discounting. Consequently, time perception is fundamental to IC and it is crucial to understand the mechanisms underlying time processing in different situations; to investigate when human time perception differs from time as represented by the calendar metric system; and to study how time perception predicts choices. This paper surveys the recent literature on time perception in order to discuss the measuring of IC through time-perception specificities. The notion of self is also discussed within this temporal perspective. If time perception modulates discounting, and time perception is related to self, the relationship between self and time perception becomes a new path to be explored in the IC studies.

  4. The direction of time

    CERN Document Server

    Reichenbach, Hans

    1999-01-01

    Ever a source of philosophical conjecture and debate, the concept of time represents the beating heart of physics. This final work by the distinguished physicist Hans Reichenbach represents the culmination and integration of a lifetime's philosophical contributions and inquiries into the analysis of time. The result is an outstanding overview of such qualitative, or topological, attributes of time as order and direction.Beginning with a discussion of the emotive significance of time, Reichenbach turns to an examination of the time order of mechanics, the time direction of thermodynamics and m

  5. Children, Time, and Play

    DEFF Research Database (Denmark)

    Elkind, David; Rinaldi, Carla; Flemmert Jensen, Anne

    Proceedings from the conference "Children, Time, and Play". Danish University of Education, January 30th 2003.......Proceedings from the conference "Children, Time, and Play". Danish University of Education, January 30th 2003....

  6. Pain dilates time perception

    National Research Council Canada - National Science Library

    Amandine E Rey; George A Michael; Corina Dondas; Marvin Thar; Luis Garcia-Larrea; Stéphanie Mazza

    2017-01-01

    .... We show that being in pain leads to an expansion of subjective time whereby a stronger increase in pain perception relative to non-painful stimulation leads to a stronger time-estimate distortion...

  7. Time, Self & Intertemporal Choice

    OpenAIRE

    Cintia eRetz Lucci

    2013-01-01

    Neuroscientific studies of intertemporal choice (IC) have focused mainly on the neural representation of self-control mechanisms and valuation. This reflects what has been considered as the core of the IC phenomenon. The claim of this paper is that deviations from exponential reward discounting as a function of time might be fully accounted for by the deviation of subjective time from calendar time. This claim is based on evidence that specificities of time perception can modulate discounting...

  8. Successful time management

    CERN Document Server

    Forsyth, Patrick

    2016-01-01

    Packed with tips and techniques, Successful Time Management serves as a guide to reviewing and assessing new work practices to improve time management. It includes great time-saving ideas, practical solutions, checklists, and advice on controlling paperwork, delegating and working with others, prioritizing to focus on key issues, and getting and staying organized. This new third edition contains new practical tips on using email in a time effective manner and dealing with other internet-based tools and apps to help productivity.

  9. International atomic time and time transfer

    Science.gov (United States)

    Lewandowski, Wlodzimierz

    Global Navigation Satellite Systems (GNSS) keep a central role in the international timekeeping. American Global Positioning System (GPS) is a navigation system that has proven itself to be a reliable source of positioning for both the military community and the civilian community. But, little known by many, is the fact that GPS has proven itself to be an important and valuabe utility to the timekeeping community (Lewandowski et al. 1999). GPS is a versatile and global tool which can be used to both distribute time to an arbitrary number of users and synchronise clocks over large distances with a high degree of precision and accuracy. Similar performance can be obtained with Russian Global Navigation Satellite System (GLONASS). It is expected in the near future satellites of a new European navigation system GALILEO might bring some important opportunities for international timekeeping. This paper after a brief introduction to international timekeeping focuses on the description of recent progress in time transfer techniques using GNSS satellites.

  10. Discrete-Time Systems

    Indian Academy of Sciences (India)

    systems, robots, space applications, farming, biotech- nology and even medicine. The disciplines of continuous-time and discrete-time sig- nals and systems have become increasingly entwined. Without any doubt, it is advantageous to process conti- nuous-time signals by sampling them. The computer control system for a ...

  11. Toddler Reading Time

    Science.gov (United States)

    ... Food Shopping Healthy Drinks for Kids Toddler Reading Time KidsHealth > For Parents > Toddler Reading Time Print A A A What's in this article? ... Kids make big leaps in vocabulary during this time, and learn about letters, shapes, colors, weather, animals, ...

  12. Time series analysis.

    NARCIS (Netherlands)

    2013-01-01

    Time series analysis can be used to quantitatively monitor, describe, explain, and predict road safety developments. Time series analysis techniques offer the possibility of quantitatively modelling road safety developments in such a way that the dependencies between the observations of time series

  13. Trends in Time

    NARCIS (Netherlands)

    Andries van den Broek; Koen Breedveld; Jos de Haan; Joep de Hart; Frank Huysmans

    2004-01-01

    How do the Dutch spend their time? How much time for example do they devote to remunerated work, care, reading or voluntary work? And: how is time structured in Dutch society? To what extent is Sunday still a special day? The Social and Cultural Planning Office has been participating in a

  14. Testing Timed Automata

    NARCIS (Netherlands)

    Springintveld, Jan; Vaandrager, Frits; d' Argenio, P.R.

    2001-01-01

    We present a generalization of the classical theory of testing for Mealy machines to a setting of dense real-time systems. A model of timed I/O automata is introduced, inspired by the timed automaton model of Alur and Dill, together with a notion of test sequence for this model. Our main

  15. Testing Timed Automata

    NARCIS (Netherlands)

    Springintveld, Jan; Vaandrager, Frits; d' Argenio, P.R.

    We present a generalization of the classical theory of testing for Mealy machines to a setting of dense real-time systems. A model of timed I/O automata is introduced, inspired by the timed automaton model of Alur and Dill, together with a notion of test sequence for this model. Our main

  16. Buying time promotes happiness

    NARCIS (Netherlands)

    Whillans, Ashley; Dunn, Elizabeth; Smeets, Paul M.; Bekkers, R.H.F.P.; Norton, M.I.

    2017-01-01

    Around the world, increases in wealth have produced an unintended consequence: a rising sense of time scarcity. We provide evidence that using money to buy time can provide a buffer against this time famine, thereby promoting happiness. Using large, diverse samples from the United States, Canada,

  17. Modelling urban travel times

    NARCIS (Netherlands)

    Zheng, F.

    2011-01-01

    Urban travel times are intrinsically uncertain due to a lot of stochastic characteristics of traffic, especially at signalized intersections. A single travel time does not have much meaning and is not informative to drivers or traffic managers. The range of travel times is large such that certain

  18. Time and man

    CERN Document Server

    Elton, L. R. B

    1978-01-01

    Time and Man focuses on the endeavors of humans to probe the mysteries of time and to elucidate its properties. The discussions are both philosophical and factual in nature and encompass science as well as the physical sciences, biology and related disciplines (for example, evolution), and the humanities (for example, religion). Factual information is presented to help the reader gain a better understanding of the concepts associated with time.Comprised of nine chapters, this volume first considers the passage of time and the experiences which humans associate with the concept of time before r

  19. Dirac quantum time mirror

    Science.gov (United States)

    Reck, Phillipp; Gorini, Cosimo; Goussev, Arseni; Krueckl, Viktor; Fink, Mathias; Richter, Klaus

    2017-04-01

    Both metaphysical and practical considerations related to time inversion have intrigued scientists for generations. Physicists have strived to devise and implement time-inversion protocols, in particular different forms of "time mirrors" for classical waves. Here we propose an instantaneous time mirror for quantum systems, i.e., a controlled time discontinuity generating wave function echoes with high fidelities. This concept exploits coherent particle-hole oscillations in a Dirac spectrum in order to achieve population reversal, and can be implemented in systems such as (real or artificial) graphene.

  20. THE EFFECT OF KETAMINE AND ITS COMBINATION WITH INDOL-2-CARBOXYLIC ACID AND CAROVERINE ON SURVIVAL TIME OF MICE WITH EXPERIMENTAL TETANUS

    Directory of Open Access Journals (Sweden)

    Indira Mujezinović

    2017-12-01

    Full Text Available Tetanus, also known as lockjaw, is a very dangerous infectious acute, usually afebrile disease characterized by muscle spasms, affecting humans and various animal species. The causative agent of the disease is bacteria Clostridium tetani. This bacteria produces a specific neurotoxin known as Tetanus toxin, which consists of two components: tetanospasmin and tetanolysin. Light (L chains of tetanospamin cleavage synaptobrevin, an integral membrane component of the synaptic vesicles, which in turn prevent release of the inhibitory neurotransmitter γ-aminobutyric acid (GABA into the synaptic cleft. The α- motor neurons are, therefore, under no inhibitory control as a result of which they undergo sustained excitatory discharge causing the characteristic motor spasms of tetanus. In this research, we attempted to normalize the disorders caused by tetanus toxin by using ketamine, a non-competitive antagonist of aspartate (at doses of 5, 10, 44 and 100 mg/kg of body weight – b.w., alone and in combination with indol-2-carboxylic acid, a competitive antagonist of aspartate (at a dose of 10 mg/kg b.w. and caroverine, a non-competitive antagonist of glutamate (at a dose of 1.2 mg/kg b.w.. Experiments were conducted on the albino mice of both sexes, weighing around 20-25 g. Experimental tetanus was induced by application of tetanus toxin. The administration of ketamine, alone and in combination with indol-2-carboxylic acid and caroverine was carried out 24 hours after administration of tetanus toxin once per day, until the mice died. It was found that ketamine had an effect only at a dose of 10 mg/kg b.w., which slightly prolonged the LD50 periodin experimental group of mice, compared to the control group of mice with experimental tetanus. Thus, it can be concluded that administration of ketamine in this dose proved to be only slightly effective. On the other hand, combination of ketamine with indol-2-carboxylic acid slightly extended the survival time

  1. The representation of time.

    Directory of Open Access Journals (Sweden)

    Elena Olivo

    2009-06-01

    Full Text Available The contemporary complexity has changed and conditioned the spatiality. The concept of space is more and more articulated and complex, it is attached to the concept of Time. It is necessary to research constitutives and structural elements of the contemporary Space-Time. The Contemporary needs plan of Time. In the Contemporary “the depth of Time” succeed to the “depth of Space”, and the Project became project of time in different scales, with different shaps, in different ways. In architecture and urbanistic composition everything depends on the measure of time against space. Perhaps, after music, the most perfect metrical expression of time, no other expressive activity requires as specifically characteristic a use of Time, as compositional material, as does the architecture and town-planning scheme.

  2. Buying time promotes happiness.

    Science.gov (United States)

    Whillans, Ashley V; Dunn, Elizabeth W; Smeets, Paul; Bekkers, Rene; Norton, Michael I

    2017-08-08

    Around the world, increases in wealth have produced an unintended consequence: a rising sense of time scarcity. We provide evidence that using money to buy time can provide a buffer against this time famine, thereby promoting happiness. Using large, diverse samples from the United States, Canada, Denmark, and The Netherlands (n = 6,271), we show that individuals who spend money on time-saving services report greater life satisfaction. A field experiment provides causal evidence that working adults report greater happiness after spending money on a time-saving purchase than on a material purchase. Together, these results suggest that using money to buy time can protect people from the detrimental effects of time pressure on life satisfaction.

  3. Where Times Meet

    Directory of Open Access Journals (Sweden)

    Theodore R. Schatzki

    2006-01-01

    Full Text Available This essay pursues two goals: (1 to argue that two fundamental types of time—the time of objective reality and “the time of the soul”—meet in human activity and history and (2 to defend the legitimacy of calling a particular version of the second type a kind of time. The essay begins by criticizing Paul Ricoeur’s version of the claim that times of these two sorts meet in history. It then presents an account of human activity based on Heidegger’s Being and Time, according to which certain times of the two types—existential temporality and succession—meet in human activity. The legitimacy of calling existential temporality a kind of time is then defended via an expanded analysis of activity that examines where the two times meet there. The concluding section briefly considers a conception of historical time due to David Carr before showing why history is a broader domain encompassing human activity where the two times meet.

  4. Where Times Meet

    Directory of Open Access Journals (Sweden)

    Theodore R. Schatzki

    2005-01-01

    Full Text Available This essay pursues two goals: (1 to argue that two fundamental types of time—the time of objective reality and “the time of the soul”—meet in human activity and history and (2 to defend the legitimacy of calling a particular version of the second type a kind of time. The essay begins by criticizing Paul Ricoeur’s version of the claim that times of these two sorts meet in history. It then presents an account of human activity based on Heidegger’s Being and Time, according to which certain times of the two types—existential temporality and succession—meet in human activity. The legitimacy of calling existential temporality a kind of time is then defended via an expanded analysis of activity that examines where the two times meet there. The concluding section briefly considers a conception of historical time due to David Carr before showing why history is a broader domain encompassing human activity where the two times meet.

  5. General regression neural network and Monte Carlo simulation model for survival and growth of Salmonella on raw chicken skin as a function of serotype, temperature and time for use in risk assessment

    Science.gov (United States)

    A general regression neural network and Monte Carlo simulation model for predicting survival and growth of Salmonella on raw chicken skin as a function of serotype (Typhimurium, Kentucky, Hadar), temperature (5 to 50C) and time (0 to 8 h) was developed. Poultry isolates of Salmonella with natural r...

  6. Time Perception and Psychiatric Disorders

    Directory of Open Access Journals (Sweden)

    Hatice Ceviz

    2013-09-01

    Full Text Available Time perception is an ability which we use in every moment of daily life, that guides the formation and continuation of our behaviors and from an evolutionary perspective ensures survival. Internal clock models help us to understand time perception. Time perception is known to vary between individuals and particular situations. This variability is explained with the mechanisms which is associated with the processes related to attention, the speed of the internal clock and the memory unit. It is suggested that time perception is mainly associated with the activities of dopamine and acetylcholine. Some dopaminergic psychoactive substances like cocaine and amphetamine have all been shown to change time perception by increasing the speed of internal clock while on the other hand some antipsychotic drugs make an opposite change in time perception by descreasing the speed of the clock. Similarly, time perception is affected in some psychiatric disorders and an ethiopathological relationship between time perception disturbances and psychiatric disorders is suggested. In this article time perception changes in schizophrenia, attention deficit/hyperactivity syndrome, depression, anxiety disorders and personality disorders are briefly reviewed.

  7. Differential inequality trends over time in survival among U.S. children with acute lymphoblastic leukemia by race/ethnicity, age at diagnosis, and sex

    National Research Council Canada - National Science Library

    Wang, Linwei; Bhatia, Smita; Gomez, Scarlett Lin; Yasui, Yutaka

    2015-01-01

    ...) have changed over time in different race/ethnicity groups. Children diagnosed with a first primary malignant ALL at ages 0 to 19 years in 1975-2010 in the nine Surveillance, Epidemiology, and End Results cancer registries were included...

  8. The Oppressor School Time

    Directory of Open Access Journals (Sweden)

    Nuno Vieira

    2013-11-01

    Full Text Available Time conceptions have had an evolution along the time, defining itself as one key element for both social and scientific activities. Nowadays time studies does not belong to a specific scientific subject, it has a multi-referential status and its study must be based on multidisciplinary perspectives. Even our circadian times are ruled by external entities such as work, and we learn to walk by the (temporal rhythms at school. Time rulers, like clocks, bells, rings, defines our lives and the way we live them, undertaken by a global synchronism. This synchronic activities oppresses (Freire our lives because it overrules our inner time and dictates the way we live in the moment that we start going to school.

  9. Time-Darts

    DEFF Research Database (Denmark)

    Jørgensen, Kenneth Yrke; Larsen, Kim Guldstrand; Srba, Jiri

    2012-01-01

    in order to compare the performance of time-darts and the complete discretization. The main conclusion is that in all our experiments the time-dart method outperforms the complete discretization and it scales significantly better for models with larger constants. [45] Verification of Liveness Properties......Symbolic data structures for model checking timed systems have been subject to a significant research, with Difference Bound Matrices (DBMs) still being the preferred data structure in several mature verification tools. In comparison, discretization offers an easy alternative, with all operations...... having linear-time complexity in the number of clocks, and yet valid for a large class of closed systems. Unfortunately, fine-grained discretization causes itself a state-space explosion. We introduce a new data structure called time-darts for the symbolic representation of state-spaces of timed automata...

  10. Identifying Some Risk Factors for the Time to Death of the Elderly Using the Semi-Parametric Blended Model of Survival Analysis With Competing Risks

    Directory of Open Access Journals (Sweden)

    Samane Hajiabbasi

    2018-01-01

    Conclusion In single-variable fitting, age, history of myocardial infarction, history of stroke, and kidney problems were identified to have significant effects on the time to death of the elderly. Based on one-variable semi-parametric competing risk mixture fitted models, more significant risk factors for the time to death of elderly was identified when compared with a fitted multivariate mode to the data. This implies that the role of some independent variables can be explained by other independent variables.

  11. Happiness and time allocation

    OpenAIRE

    Baucells, Manel; Sarin, Rakesh K.

    2007-01-01

    We consider a resource allocation problem in which time is the principal resource. Utility is derived from time-consuming leisure activities, as well as from consumption. To acquire consumption, time needs to be allocated to income generating activities (i.e., work). Leisure (e.g., social relationships, family and rest) is considered a basic good, and its utility is evaluated using the Discounted Utility Model. Consumption is adaptive and its utility is evaluated using a reference-dependent m...

  12. TIME MANAGEMENT FOR ACCOUNTANTS

    Directory of Open Access Journals (Sweden)

    Cristina Elena BIGIOI

    2016-06-01

    Full Text Available Time is money. Every accountant knows that. In our country, the taxes are changing frequently. The accountants have to update their fiscal knowledge. The purpose of the article is to find how the accountants manage their time, taking into consideration the number of fiscal declarations and the fiscal changes. In this article we present some ways to improve time management for accountants.

  13. Timed Extensions for SDL

    OpenAIRE

    Bozga, Marius; Graf, Susanne; Mounier, Laurent; Ober, Iulian; Roux, Jean-Luc; Vincent, Daniel

    2001-01-01

    International audience; In this paper we propose some extensions necessary to enable the specification and description language SDL to become an appropriate formalism for the design of real-time and embedded systems. The extensions we envisage concern both roles of SDL: First, in order to make SDL a real-time specification language, allowing to correctly simulate and verify real-time specifications, we propose a set of annotations to express in a flexible way assumptions and assertions on tim...

  14. Characteristic Time Model Validation

    Science.gov (United States)

    1988-09-01

    Characteristic Time Model Validation Final Technical Report .’ ". Tallio, R.C. Prior, Jr., and A. M. Mellor* U.S. Army Research Office Contract...Park, NC 27709-2211 I N I 11, TITLE (Include Securrty Cassification) Characteristic Time Model Validation (unclassified)512 PERSONAL AUTHOR(S) Tallio...number) FIELD GROUP SUB-GROUP Two-dimensional confined shear layers; two-dimensional prefilming airblast atomizers; characteristic time model; finite

  15. Ensemble Pulsar Time Scale

    Science.gov (United States)

    Yin, Dong-shan; Gao, Yu-ping; Zhao, Shu-hong

    2017-07-01

    Millisecond pulsars can generate another type of time scale that is totally independent of the atomic time scale, because the physical mechanisms of the pulsar time scale and the atomic time scale are quite different from each other. Usually the pulsar timing observations are not evenly sampled, and the internals between two data points range from several hours to more than half a month. Further more, these data sets are sparse. All this makes it difficult to generate an ensemble pulsar time scale. Hence, a new algorithm to calculate the ensemble pulsar time scale is proposed. Firstly, a cubic spline interpolation is used to densify the data set, and make the intervals between data points uniform. Then, the Vondrak filter is employed to smooth the data set, and get rid of the high-frequency noises, and finally the weighted average method is adopted to generate the ensemble pulsar time scale. The newly released NANOGRAV (North American Nanohertz Observatory for Gravitational Waves) 9-year data set is used to generate the ensemble pulsar time scale. This data set includes the 9-year observational data of 37 millisecond pulsars observed by the 100-meter Green Bank telescope and the 305-meter Arecibo telescope. It is found that the algorithm used in this paper can reduce effectively the influence caused by the noises in pulsar timing residuals, and improve the long-term stability of the ensemble pulsar time scale. Results indicate that the long-term (> 1 yr) stability of the ensemble pulsar time scale is better than 3.4 × 10-15.

  16. Utilizing Fractal Time

    Science.gov (United States)

    Marks-Tarlow, Terry

    Linear concepts of time plus the modern capacity to track history emerged out of circular conceptions characteristic of ancient and traditional cultures. A fractal concept of time lies implicitly within the analog clock, where each moment is treated as unique. With fractal geometry the best descriptor of nature, qualities of self-similarity and scale invariance easily model her endless variety and recursive patterning, both in time and across space. To better manage temporal aspects of our lives, a fractal concept of time is non-reductive, based more on the fullness of being than on fragments of doing. By using a fractal concept of time, each activity or dimension of life is multiply and vertically nested. Each nested cycle remains simultaneously present, operating according to intrinsic dynamics and time scales. By adding the vertical axis of simultaneity to the horizontal axis of length, time is already full and never needs to be filled. To attend to time's vertical dimension is to tap into the imaginary potential for infinite depth. To switch from linear to fractal time allows us to relax into each moment while keeping in mind the whole.

  17. Variable camshaft timing system

    Energy Technology Data Exchange (ETDEWEB)

    Butterfield, R.P.; Smith, F.R.

    1989-09-05

    This patent describes an improvement in a variable camshaft timing system for an internal combustion engine having intake and exhaust valves and a camshaft for each of the intake and exhaust valves, an intake sprocket and an exhaust sprocket keyed to their respective camshaft, only one of the camshafts being directly driven by an engine crankshaft, and a timing chain engaging both sprockets. The improvement comprising a single bracket carrying at least one idler sprocket engaging the timing chain, the bracket being mounted for movement to alter the timing relationship between the intake and exhaust sprockets.

  18. Environmental stress and flowering time

    OpenAIRE

    Riboni, Matteo; Robustelli Test, Alice; Galbiati, Massimo; Tonelli, Chiara; Conti, Lucio

    2014-01-01

    Plants maximize their chances to survive adversities by reprogramming their development according to environmental conditions. Adaptive variations in the timing to flowering reflect the need for plants to set seeds under the most favorable conditions. A complex network of genetic pathways allows plants to detect and integrate external (e.g., photoperiod and temperature) and/or internal (e.g., age) information to initiate the floral transition. Furthermore different types of environmental stre...

  19. Time Functions as Utilities

    Science.gov (United States)

    Minguzzi, E.

    2010-09-01

    Every time function on spacetime gives a (continuous) total preordering of the spacetime events which respects the notion of causal precedence. The problem of the existence of a (semi-)time function on spacetime and the problem of recovering the causal structure starting from the set of time functions are studied. It is pointed out that these problems have an analog in the field of microeconomics known as utility theory. In a chronological spacetime the semi-time functions correspond to the utilities for the chronological relation, while in a K-causal (stably causal) spacetime the time functions correspond to the utilities for the K + relation (Seifert’s relation). By exploiting this analogy, we are able to import some mathematical results, most notably Peleg’s and Levin’s theorems, to the spacetime framework. As a consequence, we prove that a K-causal (i.e. stably causal) spacetime admits a time function and that the time or temporal functions can be used to recover the K + (or Seifert) relation which indeed turns out to be the intersection of the time or temporal orderings. This result tells us in which circumstances it is possible to recover the chronological or causal relation starting from the set of time or temporal functions allowed by the spacetime. Moreover, it is proved that a chronological spacetime in which the closure of the causal relation is transitive (for instance a reflective spacetime) admits a semi-time function. Along the way a new proof avoiding smoothing techniques is given that the existence of a time function implies stable causality, and a new short proof of the equivalence between K-causality and stable causality is given which takes advantage of Levin’s theorem and smoothing techniques.

  20. Time Here, Time There, Time Everywhere: Teaching Young Children Time through Daily Routine

    Science.gov (United States)

    Lee, Joohi; Lee, Joo Ok; Fox, Jill

    2009-01-01

    According to Piaget, 5- or 6-year-old children gradually acquire the concept of time based on events (Piaget, 1969). In his experiment of investigating children's time concepts, Piaget found that children of these ages were able to place pictures based on sequential events with some errors; the younger children made more errors. The National…

  1. Time and Teaching

    Science.gov (United States)

    Zielinski, Theresa Julia; Brooks, David W.; Crippen, Kent J.; March, Joe L.

    2001-06-01

    Time management is an important issue for teachers and students. This article discusses teachers' use of time from the perspective of curriculum and instruction. Average high school students spend fewer than 5 hours per week in outside-of-class study; average college students spend about 20 hours. Procrastination, often viewed in a negative light by teachers, usually pays off so well for college students that seniors become better at it than freshmen. Three suggestions for designing instruction are: test early and often; do not waste the best students' time in an effort to improve overall performance; and use engaging activities that motivate students to give of their time. The impact of computers on curricula is a double-edged sword. Time must be devoted to teaching the use of applications, but the programs reduce busywork. Will this turn out to be a simple tradeoff, or will the programs make us much more efficient so that less time is required? Will computer programs ultimately lead to an expanded criterion for expertise, thus demanding even more time to become an expert? These issues are described and suggestions for controlling time during instruction are provided.

  2. Peircean diagrams of time

    DEFF Research Database (Denmark)

    Øhrstrøm, Peter

    2011-01-01

    Some very good arguments can be given in favor of the Augustinean wisdom, according to which it is impossible to provide a satisfactory definition of the concept of time. However, even in the absence of a proper definition, it is possible to deal with conceptual problems regarding time. It can be...

  3. Time Distortions in Mind

    OpenAIRE

    Vatakis, A.; Allman, M.

    2015-01-01

    Time Distortions in Mind brings together current research on temporal processing in clinical populations to elucidate the interdependence between perturbations in timing and disturbances in the mind and brain. For the student, the scientist, and the stepping-stone for further research.

  4. Shackle in Time

    DEFF Research Database (Denmark)

    Madsen, Mogens Ove

    2016-01-01

    GLS Shackle got much and the crucial inspiration from John Maynard Keynes. But that’s not all. He took a number of further consequences of Keynes’ thoughts. This implies for example ideal claims to economists — having to deal with both mechanical time and expectational time. In consequence the idea...

  5. Timing of breastfeeding

    Science.gov (United States)

    ... the breast for longer periods of time. Frequent nursing for growth spurts is temporary. After a few days, your milk supply will increase to provide enough milk at each feeding. Then your baby will eat less often and for shorter periods of time.

  6. Trauma resuscitation time.

    NARCIS (Netherlands)

    Olden, G.D.J. van; Vugt, A.B. van; Biert, J.; Goris, R.J.A.

    2003-01-01

    Documenting the timing and organisation of trauma resuscitation can be utilised to assess performance standards, and to ensure a high quality of trauma resuscitation procedures. Since there is no European literature available on trauma resuscitation time (TRT) in the emergency room, the aim of this

  7. Time Will Tell

    DEFF Research Database (Denmark)

    Dalsgård, Anne Line

    2017-01-01

    in the neighbourhood, as credit credit cards are locked in a punctuated time, where dates are crucial. Using an episode that I happened to be part of as point of departure, I argue that decepção is the estrangement experienced, when a moment of trust is thrown back upon you, distorted by the process of time....

  8. Babies Need Tummy Time

    Science.gov (United States)

    ... Look Like? How Can Caregivers Create a Safe Sleep Environment? Babies Need Tummy Time! FAQs Myths and Facts ​​​​​​​​​​​​​​​​​​​​​​​​​​​ Printer-Friendly Email Page Skip sharing on social media links Babies Need Tummy Time! Page Content Tummy ...

  9. Time management and procrastination

    NARCIS (Netherlands)

    van Eerde, W.; Mumford, M.D.; Frese, M.

    2015-01-01

    This chapter combines the topics time management and procrastination. Time management is an overarching term derived from popular notions on how to be effective at work. Procrastination has been mainly researched from a personality perspective, addressing the emotional and psychological issues of

  10. Real Time Systems

    DEFF Research Database (Denmark)

    Christensen, Knud Smed

    2000-01-01

    Describes fundamentals of parallel programming and a kernel for that. Describes methods for modelling and checking parallel problems. Real time problems.......Describes fundamentals of parallel programming and a kernel for that. Describes methods for modelling and checking parallel problems. Real time problems....

  11. Dwell-time switching

    NARCIS (Netherlands)

    Cao, Ming; Morse, A. Stephen

    Dwell-time switching is a logic for orchestrating the switching between controllers in a family of candidate controllers in order to control a process with a highly uncertain model. An analysis is given of dwell-time switching which is appropriate to a variety of control problems in which the class

  12. Time - A Traveler's Guide

    Science.gov (United States)

    Pickover, Clifford A.

    1999-09-01

    "Bucky Fuller thought big," Wired magazine recently noted, "Arthur C. Clarke thinks big, but Cliff Pickover outdoes them both." In his newest book, Cliff Pickover outdoes even himself, probing a mystery that has baffled mystics, philosophers, and scientists throughout history--What is the nature of time?In Time: A Traveler's Guide , Pickover takes readers to the forefront of science as he illuminates the most mysterious phenomenon in the universe--time itself. Is time travel possible? Is time real? Does it flow in one direction only? Does it have a beginning and an end? What is eternity? Pickover's book offers a stimulating blend of Chopin, philosophy, Einstein, and modern physics, spiced with diverting side-trips to such topics as the history of clocks, the nature of free will, and the reason gold glitters. Numerous diagrams ensure readers will have no trouble following along.By the time we finish this book, we understand a wide variety of scientific concepts pertaining to time. And most important, we will understand that time travel is, indeed, possible.

  13. Real-Time Evaluations

    Directory of Open Access Journals (Sweden)

    UNHCR

    2002-07-01

    Full Text Available A real-time evaluation (RTE is a timely, rapid andinteractive review of a fast evolving humanitarianoperation undertaken at an early phase. Its broadobjectives are to gauge the effectiveness and impactof a given UNHCR response and to ensure that itsfindings are used as an immediate catalyst fororganisational and operational change.

  14. ZERO-TIME INDICATOR

    Science.gov (United States)

    Sander, H.H.

    1960-08-30

    The travel time of a nuclear shock wave from its point of origin to a location can be determined accurately by an apparatus for noting and comparably recording both zerotime, as indicated by the electromagnetic transient associated with the nuclear detonation, and shock wave arrival time.

  15. The commuting time paradox

    NARCIS (Netherlands)

    van Ommeren, J.N.; Rietveld, P.

    2005-01-01

    We examine the conditions for the 'commuting time paradox' which states that the average commuting time does not vary between different periods. We develop therefore an equilibrium job search model with endogenously chosen commuting costs. Presuming wage bargaining between workers and firms, the

  16. Transition path time distributions

    Science.gov (United States)

    Laleman, M.; Carlon, E.; Orland, H.

    2017-12-01

    Biomolecular folding, at least in simple systems, can be described as a two state transition in a free energy landscape with two deep wells separated by a high barrier. Transition paths are the short part of the trajectories that cross the barrier. Average transition path times and, recently, their full probability distribution have been measured for several biomolecular systems, e.g., in the folding of nucleic acids or proteins. Motivated by these experiments, we have calculated the full transition path time distribution for a single stochastic particle crossing a parabolic barrier, including inertial terms which were neglected in previous studies. These terms influence the short time scale dynamics of a stochastic system and can be of experimental relevance in view of the short duration of transition paths. We derive the full transition path time distribution as well as the average transition path times and discuss the similarities and differences with the high friction limit.

  17. Leisure Time Invention

    DEFF Research Database (Denmark)

    Davis, Lee N.; Davis, Jerome D.; Hoisl, Karin

    2013-01-01

    This paper studies the contextual factors that influence whether invention occurs during work time or leisure time. Leisure time invention, a potentially important but thus far largely unexplored source of employee creativity, refers to invention where the main underlying idea occurs while...... the employee is away from the workplace. We build on existing theory in the fields of organizational creativity and knowledge recombination, especially work relating context to creativity. The paper’s main theoretical contribution is to extend our understanding of the boundaries of employee creativity...... by adding to the discussion of how access to and exploitation of different types of resources—during work hours or during leisure time — may affect creativity. Based on survey data from more than 3,000 inventions from German employee inventors, we find that leisure time inventions are more frequently...

  18. Time for memory

    DEFF Research Database (Denmark)

    Murakami, Kyoko

    2012-01-01

    This article is a continuous dialogue on memory triggered by Brockmeier’s (2010) article. I drift away from the conventionalization of the archive as a spatial metaphor for memory in order to consider the greater possibility of “time” for conceptualizing memory. The concept of time is central...... to understanding the nature of human experience as a process in which a constant flux of change in organism, cultural and social practices is observed. Two categories of time have been explored, firstly the Aristotelian, physical time for an experimental paradigm, and secondly, the way in which we experience time...... in terms of autobiographical memory. The second category of time is discussed, drawing on Augustine and Bergson amongst others. Bergson’s notion of duration has been considered as a promising concept for a better understanding of autobiographical memory. Psychological phenomena such as autobiographical...

  19. Time, money, and morality.

    Science.gov (United States)

    Gino, Francesca; Mogilner, Cassie

    2014-02-01

    Money, a resource that absorbs much daily attention, seems to be involved in much unethical behavior, which suggests that money itself may corrupt. This research examined a way to offset such potentially deleterious effects-by focusing on time, a resource that tends to receive less attention than money but is equally ubiquitous in daily life. Across four experiments, we examined whether shifting focus onto time can salvage individuals' ethicality. We found that implicitly activating the construct of time, rather than money, leads individuals to behave more ethically by cheating less. We further found that priming time reduces cheating by making people reflect on who they are. Implications for the use of time primes in discouraging dishonesty are discussed.

  20. Modeling Complex Time Limits

    Directory of Open Access Journals (Sweden)

    Oleg Svatos

    2013-01-01

    Full Text Available In this paper we analyze complexity of time limits we can find especially in regulated processes of public administration. First we review the most popular process modeling languages. There is defined an example scenario based on the current Czech legislature which is then captured in discussed process modeling languages. Analysis shows that the contemporary process modeling languages support capturing of the time limit only partially. This causes troubles to analysts and unnecessary complexity of the models. Upon unsatisfying results of the contemporary process modeling languages we analyze the complexity of the time limits in greater detail and outline lifecycles of a time limit using the multiple dynamic generalizations pattern. As an alternative to the popular process modeling languages there is presented PSD process modeling language, which supports the defined lifecycles of a time limit natively and therefore allows keeping the models simple and easy to understand.

  1. The Design and Analysis of Salmonid Tagging Studies in the Columbia Basin : Volume XVII : Effects of Ocean Covariates and Release Timing on First Ocean-Year Survival of Fall Chinook Salmon from Oregon and Washington Coastal Hatcheries.

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, Caitlin; Skalski, John R.

    2001-05-01

    Effects of oceanographic conditions, as well as effects of release-timing and release-size, on first ocean-year survival of subyearling fall chinook salmon were investigated by analyzing CWT release and recovery data from Oregon and Washington coastal hatcheries. Age-class strength was estimated using a multinomial probability likelihood which estimated first-year survival as a proportional hazards regression against ocean and release covariates. Weight-at-release and release-month were found to significantly effect first year survival (p < 0.05) and ocean effects were therefore estimated after adjusting for weight-at-release. Negative survival trend was modeled for sea surface temperature (SST) during 11 months of the year over the study period (1970-1992). Statistically significant negative survival trends (p < 0.05) were found for SST during April, June, November and December. Strong pairwise correlations (r > 0.6) between SST in April/June, April/November and April/December suggest the significant relationships were due to one underlying process. At higher latitudes (45{sup o} and 48{sup o}N), summer upwelling (June-August) showed positive survival trend with survival and fall (September-November) downwelling showed positive trend with survival, indicating early fall transition improved survival. At 45{sup o} and 48{sup o}, during spring, alternating survival trends with upwelling were observed between March and May, with negative trend occurring in March and May, and positive trend with survival occurring in April. In January, two distinct scenarios of improved survival were linked to upwelling conditions, indicated by (1) a significant linear model effect (p < 0.05) showing improved survival with increasing upwelling, and (2) significant bowl-shaped curvature (p < 0.05) of survival with upwelling. The interpretation of the effects is that there was (1) significantly improved survival when downwelling conditions shifted to upwelling conditions in January (i

  2. Design and Analysis of Salmonid Tagging Studies in the Columbia Basin : Evaluating Wetland Restoration Projects in the Columbia River Estuary using Hydroacoustic Telemetry Arrays to Estimate Movement, Survival, and Residence Times of Juvenile Salmonids, Volume XXII (22).

    Energy Technology Data Exchange (ETDEWEB)

    Perry, Russell W.; Skalski, John R.

    2008-08-01

    Wetlands in the Columbia River estuary are actively being restored by reconnecting these habitats to the estuary, making more wetland habitats available to rearing and migrating juvenile salmon. Concurrently, thousands of acoustically tagged juvenile salmonids are released into the Columbia River to estimate their survival as they migrate through the estuary. Here, we develop a release-recapture model that makes use of these tagged fish to measure the success of wetland restoration projects in terms of their contribution to populations of juvenile salmon. Specifically, our model estimates the fraction of the population that enter the wetland, survival within the wetland, and the mean residence time of fish within the wetland. Furthermore, survival in mainstem Columbia River downstream of the wetland can be compared between fish that remained the mainstem and entered the wetland. These conditional survival estimates provide a means of testing whether the wetland improves the subsequent survival of juvenile salmon by fostering growth or improving their condition. Implementing such a study requires little additional cost because it takes advantage of fish already released to estimate survival through the estuary. Thus, such a study extracts the maximum information at minimum cost from research projects that typically cost millions of dollars annually.

  3. Construction time of PWRs

    Energy Technology Data Exchange (ETDEWEB)

    Carajilescov, Pedro; Moreira, Joao M.L., E-mail: pedro.carajilescov@ufabc.edu.b, E-mail: joao.moreira@ufabc.edu.b [Universidade Federal do ABC (UFABC), Santo Andre, SP (Brazil). Center of Engineering, Modeling and Applied Social Sciences

    2011-07-01

    The cost of electricity generated by nuclear power is greatly affected by the capital cost, which is dependent on the construction time of the plant. This work analyses the construction time of PWRs in several countries with different market structure and licensing experience. Countries which succeeded to establish a more collaborative environment among utilities, constructors, regulators, and energy planners through effective partnerships were able to build PWRs in shorter times. The construction time in Germany, France and Russia was around 80 months and in Japan, about 60 months. The envelope of 95% of the cases includes a range between 50 and 250 months of construction time. The evaluations show that construction time of PWRs has been longer for countries that did not hold the technology to build their own reactors, and depended on contracts with foreign suppliers. The nominal power of the reactors was considered a measure of plant size, technology complexity and standardization. Countries with standardized reactor designs (France, Japan and Russia) were able to build plants in shorter times. (author)

  4. Time Asymmetric Quantum Mechanics

    Directory of Open Access Journals (Sweden)

    Arno R. Bohm

    2011-09-01

    Full Text Available The meaning of time asymmetry in quantum physics is discussed. On the basis of a mathematical theorem, the Stone-von Neumann theorem, the solutions of the dynamical equations, the Schrödinger equation (1 for states or the Heisenberg equation (6a for observables are given by a unitary group. Dirac kets require the concept of a RHS (rigged Hilbert space of Schwartz functions; for this kind of RHS a mathematical theorem also leads to time symmetric group evolution. Scattering theory suggests to distinguish mathematically between states (defined by a preparation apparatus and observables (defined by a registration apparatus (detector. If one requires that scattering resonances of width Γ and exponentially decaying states of lifetime τ=h/Γ should be the same physical entities (for which there is sufficient evidence one is led to a pair of RHS's of Hardy functions and connected with it, to a semigroup time evolution t_0≤t<∞, with the puzzling result that there is a quantum mechanical beginning of time, just like the big bang time for the universe, when it was a quantum system. The decay of quasi-stable particles is used to illustrate this quantum mechanical time asymmetry. From the analysis of these processes, we show that the properties of rigged Hilbert spaces of Hardy functions are suitable for a formulation of time asymmetry in quantum mechanics.

  5. Real-time shadows

    CERN Document Server

    Eisemann, Elmar; Assarsson, Ulf; Wimmer, Michael

    2011-01-01

    Important elements of games, movies, and other computer-generated content, shadows are crucial for enhancing realism and providing important visual cues. In recent years, there have been notable improvements in visual quality and speed, making high-quality realistic real-time shadows a reachable goal. Real-Time Shadows is a comprehensive guide to the theory and practice of real-time shadow techniques. It covers a large variety of different effects, including hard, soft, volumetric, and semi-transparent shadows.The book explains the basics as well as many advanced aspects related to the domain

  6. Time in physics

    CERN Document Server

    Stupar, Sandra

    2017-01-01

    One of the most important questions concerning the foundations of physics, especially since the discovery of relativity and quantum theory, is the nature and role of time. In this book we bring together researchers from different areas of physics, mathematics, computer science and philosophy to discuss the role time plays in physics. There have been few books on this topic to date, and two of the key aims of the workshop and this book are to encourage more researchers to explore this area, and to pique students’ interest in the different roles time plays in physics.

  7. Priced Timed Automata

    DEFF Research Database (Denmark)

    Behrmann, Gerd; Larsen, Kim Guldstrand; Rasmussen, Jacob Illum

    2004-01-01

    This contribution reports on the considerable effort made recently towards extending and applying well-established timed automata technology to optimal scheduling and planning problems. The effort of the authors in this direction has to a large extent been carried out as part of the European...... projects VHS [22] and AMETIST [17] and are available in the recently released UPPAAL CORA [12], a variant of the real-time verification tool UPPAAL [20,5] specialized for cost-optimal reachability for the extended model of priced timed automata....

  8. Time Series Momentum

    DEFF Research Database (Denmark)

    Moskowitz, Tobias J.; Ooi, Yao Hua; Heje Pedersen, Lasse

    2012-01-01

    We document significant “time series momentum” in equity index, currency, commodity, and bond futures for each of the 58 liquid instruments we consider. We find persistence in returns for one to 12 months that partially reverses over longer horizons, consistent with sentiment theories of initial...... under-reaction and delayed over-reaction. A diversified portfolio of time series momentum strategies across all asset classes delivers substantial abnormal returns with little exposure to standard asset pricing factors and performs best during extreme markets. Examining the trading activities...... of speculators and hedgers, we find that speculators profit from time series momentum at the expense of hedgers....

  9. Time Use and Happiness

    OpenAIRE

    Galay, Karma

    2008-01-01

    The study of time use in different Bhutanese regions presents a wide array of information related to public policy issues. For instance it was found that rural people spend quite a substantial amount of time on travel and commute as well as waiting for services to be delivered. This amounts to a waste of people's precious time since they are not able to work in their farms during such days. Such information could be very useful to our policy makers involved in planning rural roads and transpo...

  10. Smartphones and Time Zones

    Science.gov (United States)

    Baird, William; Secrest, Jeffery; Padgett, Clifford; Johnson, Wayne; Hagrelius, Claire

    2016-09-01

    Using the Sun to tell time is an ancient idea, but we can take advantage of modern technology to bring it into the 21st century for students in astronomy, physics, or physical science classes. We have employed smartphones, Google Earth, and 3D printing to find the moment of local noon at two widely separated locations. By reviewing GPS time-stamped photos from each place, we are able to illustrate that local noon is longitude-dependent and therefore explain the need for time zones.

  11. Real-time specifications

    DEFF Research Database (Denmark)

    David, A.; Larsen, K.G.; Legay, A.

    2015-01-01

    A specification theory combines notions of specifications and implementations with a satisfaction relation, a refinement relation, and a set of operators supporting stepwise design. We develop a specification framework for real-time systems using Timed I/O Automata as the specification formalism......, with the semantics expressed in terms of Timed I/O Transition Systems. We provide constructs for refinement, consistency checking, logical and structural composition, and quotient of specifications-all indispensable ingredients of a compositional design methodology. The theory is implemented in the new tool Ecdar...

  12. Epidemiological Methods: About Time

    Directory of Open Access Journals (Sweden)

    Helena Chmura Kraemer

    2009-12-01

    Full Text Available Epidemiological studies often produce false positive results due to use of statistical approaches that either ignore or distort time. The three time-related issues of focus in this discussion are: (1 cross-sectional vs. cohort studies, (2 statistical significance vs. public health significance, and (3, how risk factors "work together" to impact public health significance. The issue of time should be central to all thinking in epidemiology research, affecting sampling, measurement, design, analysis and, perhaps most important, the interpretation of results that might influence clinical and public-health decision-making and subsequent clinical research.

  13. Identity/Time

    Directory of Open Access Journals (Sweden)

    Nancy J. Knauer

    2013-09-01

    Full Text Available This paper engages the unspoken fourth dimension of intersectionality—time. Using the construction of lesbian, gay, bisexual, and transgender (LGBT identities as an example, it establishes that identity, as it is lived and experienced, is not only multivalent, but also historically contingent. It then raises a number of points regarding the temporal locality of identity—the influence of time on issues of identity and understanding, its implications for legal interventions, social movement building, and paradigms of progressive change. As the title suggests, the paper asks us to consider the frame of identity over time.

  14. Risk of early onset substance use among students with and without mild academic disabilities : Results of a discrete-time survival analysis

    NARCIS (Netherlands)

    Kepper, Annelies; Koning, Ina; Vollebergh, Wilma; Monshouwer, Karin

    2014-01-01

    This study investigated the age of onset of substance use among 536 students with mild academic disabilities and 906 students without academic disabilities, and the extent to which emotional, conduct, and hyperactivity problems explain the differences between these two groups. Using discrete-time

  15. Percutaneous coronary intervention-related time delay, patient's risk profile, and survival benefits of primary angioplasty vs lytic therapy in ST-segment elevation myocardial infarction.

    Science.gov (United States)

    De Luca, Giuseppe; Cassetti, Ettore; Marino, Paolo

    2009-07-01

    Previous reports have suggested an impact of patient's risk profile and percutaneous coronary intervention (PCI)-related time delay on the benefits of primary angioplasty as compared with fibrinolysis. However, several factors, such as inappropriate interpretation and definition of delays, missing currently available trials, and arguable risk-benefit analysis, limit the value of these reports. Thus, the aim of the current review is to assess whether the prognostic impact of PCI-related time delay may vary according to patient's risk profile, presentation delay, and type of lytic therapy. We obtained results from all randomized trials comparing fibrinolysis and primary angioplasty in ST-segment elevation myocardial infarction. The literature was scanned by formal searches of electronic databases (MEDLINE and CENTRAL) for papers published from January 1990 to April 2007. The following key words were used: randomized trial, myocardial infarction, reperfusion, primary angioplasty, rescue angioplasty, fibrinolysis, thrombolysis, duteplase, reteplase, tenecteplase, and alteplase. Major clinical end point assessed was mortality at 30-day follow-up. The relationship between mortality benefits from primary angioplasty, patient's risk profile, and PCI-related time delay was evaluated by using a weighted least-square regression in which results from each trial were weighted by the square root of the number of patients of each trial. A total of 27 trials were finally included, with 4399 patients randomized to primary angioplasty and 4474 patients randomized to fibrinolysis. The relationship between the benefits from primary angioplasty and PCI-related time changed according to risk profile. The higher the risk profile, the larger the reduction in mortality benefits from primary angioplasty as compared with fibrinolysis per each 10 minutes of PCI-related time delay (0.75%, 0.45%, and 0%, in high-, medium-, and low-risk patients, respectively). Furthermore, the impact was

  16. Musical and film time

    Directory of Open Access Journals (Sweden)

    Kulezić-Wilson Danijela

    2008-01-01

    Full Text Available Comparative analysis of linear, non-linear and multiple temporal dimensions in music and film reveals that the understanding and utilisation of time in these two arts reflect not only the aesthetic inclinations of its creators and their subjective experiences of temporality but also their philosophical views and, sometimes, spiritual beliefs. Viewed in the context of contemporary theories about Time, particularly Shallis' interpretation of different temporalities as symbolic of various levels of reality and J. T. Fraser's concept of time as a hierarchical nest of different temporalities or Umwelts, the results of this comparison lead to the conclusion that the time in which music and film unfold belongs to a separate, artificial Umwelt of its own - art-temporality.

  17. ALICE Time Projection Chamber

    CERN Multimedia

    Lippmann, C

    2013-01-01

    The Time Projection Chamber (TPC) is the main device in the ALICE 'central barrel' for the tracking and identification (PID) of charged particles. It has to cope with unprecedented densities of charges particles.

  18. Sedentary Time in Children

    DEFF Research Database (Denmark)

    Atkin, Andrew J; Ekelund, Ulf; Møller, Niels Christian

    2013-01-01

    , 800, 1100 counts-per-minute) and non-wear criteria (10-, 20-, 60-, 100-min consecutive zeros). Adiposity was assessed by sum of four skin-fold thickness measures. A clustered metabolic risk score was calculated as the mean of standardised metabolic syndrome components, including blood pressure......, insulin resistance, and inverted fasting HDL-cholesterol. Analyses were conducted using multi-level cross-sectional time-series regression, adjusted for overall physical activity (accelerometer counts per minute). Meta-analysis was used to obtain pooled estimates of the exposure-outcome association over...... on associations of sedentary time with adiposity and clustered metabolic risk. METHODS: Data were from the European Youth Heart Study, which included assessment of sedentary time by accelerometer. Sixteen sedentary time variables were constructed based upon combinations of frequently used cut-points (100, 500...

  19. Finding Time for Fitness

    Science.gov (United States)

    ... your daily exercise goal. Kicking it into high gear. If your activity sessions are vigorous, you only ... 24, 2016. No time for exercise? Try our top 10 tips to get more! American Heart Association. ...

  20. As time goes by ..

    CERN Document Server

    Nanopoulos, Dimitri V.

    1994-01-01

    A rather simple and non-technical exposition of our new approach to {\\em Time, Quantum Physics, Black-Hole dynamics}, and {\\em Cosmology}, based on non-critical string theory, is provided. A new fundamental principle, the {\\em Procrustean Principle}, that catches the essence of our approach is postulated: the low-energy world is {\\em unavoidably} an ``open" system due to the spontaneous truncation of the {\\em delocalized, topological} string modes in continuous interaction with the low-lying-{\\em localized} string modes. The origin of space-time, the expansion of the Universe, the entropy increase and accompanied irreversibility of time, as well as the collapse of the wavefunction are all very neatly tied together. Possible observable consequences include: quantum relaxation with time of the Universal, fundamental constants, like the velocity of light c and the Planck constant \\hbar decreasing towards their asymptotic values, and the cosmological constant \\Lambda_C diminishing towards zero; possible violation...

  1. Make Time for Breakfast

    Science.gov (United States)

    ... is a perfect time to enjoy fruits and vegetables children need for optimal health. Try fresh seasonal fruit alone or in cereal, add frozen fruits to yogurt or toss chopped vegetables into an omelet. Pack your breakfast to go. ...

  2. Chemistry space–time

    Directory of Open Access Journals (Sweden)

    David A. Winkler

    2015-12-01

    Full Text Available As Einstein identified so clearly, space and time are intimately related. We discuss the relationship between time and Euclidean space using spectroscopic and radioastronomical studies of interstellar chemistry as an example. Given the finite speed of light, we are clearly studying chemical reactions occurring tens of thousands of years ago that may elucidate the primordial chemistry of this planet several billion years ago. We also explore space of a different kind – chemical space, with many more dimensions than the four we associate as space–time. Vast chemical spaces also need very efficient (computational methods for their exploration to overcome this ‘curse of dimensionality’. We discuss methods by which the time to explore these new spaces can be very substantially reduced, opening the discovery useful new materials that are the key to our future.

  3. Drug Retention Times

    Energy Technology Data Exchange (ETDEWEB)

    Center for Human Reliability Studies

    2007-05-01

    The purpose of this monograph is to provide information on drug retention times in the human body. The information provided is based on plausible illegal drug use activities that might be engaged in by a recreational drug user.

  4. Musical and film time

    National Research Council Canada - National Science Library

    Kulezic-Wilson, Danijela

    2008-01-01

    Comparative analysis of linear, non-linear and multiple temporal dimensions in music and film reveals that the understanding and utilisation of time in these two arts reflect not only the aesthetic...

  5. Real-Time Logistics

    National Research Council Canada - National Science Library

    Agnes Shanley

    2017-01-01

    .... Working with T-Systems, a vendor of private cloud hosting, the companies are developing a proof of concept that would use blockchain-based smart contracts, with Roambee offering real-time product...

  6. ECAL Timing Performance

    CERN Document Server

    CMS Collaboration

    2014-01-01

    The CMS electromagnetic calorimeter (ECAL) is made of about 75000 scintillating lead tungstate crystals arranged in a barrel and two endcaps. The scintillation light is read out by avalanche photodiodes in the barrel and vacuum phototriodes in the endcaps, at which point the scintillation pulse is amplified and sampled at 40 MHz by the on-detector electronics. The fast signal from the crystal scintillation enables energy as well as timing measurements from the data collected in proton-proton collisions with high energy electrons and photons. The stability of the timing measurement required to maintain the energy resolution is on the order of 1ns. The single-channel time resolution of ECAL measured at beam tests for high energy showers is better than 100 ps. The timing resolution achieved with the data collected in proton-proton collisions at the LHC is presented.

  7. Time in the Making

    DEFF Research Database (Denmark)

    Dirckinck-Holmfeld, Katrine Remmen

    ? These are research questions Katrine Dirckinck - Holmfeld explores in the artistic research project Time in the Making: Rehearsing Reparative Critical Practices. Through the development of video installations Leap into Colour (20 12 - 2015) and movement (2012) and in dialogue with the work of artists Rania & Raed...... Rafei, Julie Ault and the cabaret Metro Al Madina in Beirut, Time in the Making investigates how to shift Sedgwick’s concept of the reparative practice from a hermeneutic reading practice to artistic practices and an image in itself. Time in the Making articulates an understanding of the reparative...... as artistic practices that style new forms of subjectivity through a complex engagement with affect, materiality and time. The Ph D project contributes to the “reparative turn” in queer feminist scholarship (Robyn Wiegman) by interweaving reparative critical practices with artistic research, as an emerging...

  8. How emotions change time.

    Science.gov (United States)

    Schirmer, Annett

    2011-01-01

    Experimental evidence suggests that emotions can both speed-up and slow-down the internal clock. Speeding up has been observed for to-be-timed emotional stimuli that have the capacity to sustain attention, whereas slowing down has been observed for to-be-timed neutral stimuli that are presented in the context of emotional distractors. These effects have been explained by mechanisms that involve changes in bodily arousal, attention, or sentience. A review of these mechanisms suggests both merits and difficulties in the explanation of the emotion-timing link. Therefore, a hybrid mechanism involving stimulus-specific sentient representations is proposed as a candidate for mediating emotional influences on time. According to this proposal, emotional events enhance sentient representations, which in turn support temporal estimates. Emotional stimuli with a larger share in ones sentience are then perceived as longer than neutral stimuli with a smaller share.

  9. Time dimension of marketing

    Directory of Open Access Journals (Sweden)

    Uzelac Nikola

    2004-01-01

    Full Text Available Time dimension of marketing has got its place in literature. For example, the time is basic independent variable in widely accepted concepts of product life cycle and diffusion of innovation. In addition, efforts have been made to bring this issue to the theoretic basis of the discipline. But, some important areas are still under researched, or even disregarded. Moreover, projects directed at investigation of the real behavior of marketing managers are rare, and in normative sense very few options have been advocated. This particularly pertains to the issues of time horizon, durability of relations with customers, timeliness of decision-making, and time allocation by managers and customers. In this regard, the literature of strategic management contains solutions which might be useful, and the ideas of some authors from marketing deserve support.

  10. How emotions change time

    Directory of Open Access Journals (Sweden)

    Annett eSchirmer

    2011-10-01

    Full Text Available Experimental evidence suggests that emotions can both speed-up and slow-down the internal clock. Speeding-up has been observed for to-be-timed emotional stimuli that have the capacity to sustain attention, whereas slowing-down has been observed for to-be-timed neutral stimuli that are presented in the context of emotional distractors. These effects have been explained by mechanisms that involve changes in bodily arousal, attention or sentience. A review of these mechanisms suggests both merits and difficulties in the explanation of the emotion-timing link. Therefore, a hybrid mechanism involving stimulus-specific sentient representations is proposed as a candidate for mediating emotional influences on time. According to this proposal, emotional events enhance sentient representations, which in turn support temporal estimates. Emotional stimuli with a larger share in ones sentience are then perceived as longer than neutral stimuli with a smaller share.

  11. Multivariate Time Series Search

    Data.gov (United States)

    National Aeronautics and Space Administration — Multivariate Time-Series (MTS) are ubiquitous, and are generated in areas as disparate as sensor recordings in aerospace systems, music and video streams, medical...

  12. Time-predictable architectures

    CERN Document Server

    Rochange, Christine; Uhrig , Sascha

    2014-01-01

    Building computers that can be used to design embedded real-time systems is the subject of this title. Real-time embedded software requires increasingly higher performances. The authors therefore consider processors that implement advanced mechanisms such as pipelining, out-of-order execution, branch prediction, cache memories, multi-threading, multicorearchitectures, etc. The authors of this book investigate the timepredictability of such schemes.

  13. Time of Open Knowledge

    OpenAIRE

    Žarnić, Berislav

    2016-01-01

    In this paper the minimal theory of temporal order has been defined and axiomatically presented. The concept of time captured by the minimal theory has been termed ‘basic time’. The concept of basic time has been divided into four types with respect to criteria of uniqueness and totality of temporal order. The exemplar scientific concepts corresponding to the three of four types have been found in the history of ideas (Newton, Kant, Einstein) and classified (strong temporal monism, weak tempo...

  14. LEADERSHIP AND TIME MANAGEMENT

    OpenAIRE

    Nikezic, Srdan; BATAVELJIC2 Dragan; NIKEZIC Stefan; BATAVELJIC Branka

    2014-01-01

    When it comes to resources, it is primarily referred to material and financial and rarely human. It is assumed that human resources are used in the right way that their involvement, measured in time and intensity, is properly set to goals and tasks. Practice, unfortunately disproves this assumption. Employees spend too much time for unnecessary and low-priority activities, not realizing that the implementation of certain, key activities the requirement for achieving the ...

  15. Time dependence of ICD

    Science.gov (United States)

    Dorner, Reinhard

    2014-05-01

    We will discuss experimental studies of ICD in van der Vaals dimers of rare gas atoms and small molecules using the COLTRIMS technique. The talk will cover ICD after resonant Auger excitation (Nature 505, 664 (2014)) and two studies unveiling the time dependence of ICD in the energy (PRL 111, 233004 (2013)) and in the time domain (PRL 111, 093401 (2013)). A new technique to make ultrafast movies without the use of short pulses will be discussed.

  16. Long time series

    DEFF Research Database (Denmark)

    Hisdal, H.; Holmqvist, E.; Hyvärinen, V.

    Awareness that emission of greenhouse gases will raise the global temperature and change the climate has led to studies trying to identify such changes in long-term climate and hydrologic time series. This report, written by the......Awareness that emission of greenhouse gases will raise the global temperature and change the climate has led to studies trying to identify such changes in long-term climate and hydrologic time series. This report, written by the...

  17. Remarriage Timing: Does Religion Matter?

    Directory of Open Access Journals (Sweden)

    Xiaohe Xu

    2017-08-01

    Full Text Available Using pooled data from the National Survey of Family Growth (NSFG 2006–2010, we examine the effects of denominational affiliation, worship service attendance, and religious salience on remarriage timing. Survival analyses indicate that both men and women affiliated with conservative Protestant faith traditions are significantly more likely than their unaffiliated and Catholic counterparts to remarry at an accelerated pace following divorce. Results further show that, net of religious affiliation and socio-demographic characteristics, worship service attendance accelerates remarriage timing, whereas the effects of religious salience are weaker or unobserved. These results are largely consistent with prior research on denominational variations in the timing of first marriage and underscore the robust influence of religion on the institution of marriage.

  18. Keeping time - Performing Place

    DEFF Research Database (Denmark)

    Dvinge, Anne Christine

    2012-01-01

    Candace Allen’s novel Valaida (2004) illustrates the migratory patterns of early 20th century jazz music and musicians, positing the art form and its performers as “heterotopians”; simultaneously in and outside of the power relations of hegemonic time-space compression, travelling in an alternate...... and performance offers an alternate space, where the radical potential lies in the moment of communication and community, constituting a diasporic practice and heterutopian spaces of sound and time.......Candace Allen’s novel Valaida (2004) illustrates the migratory patterns of early 20th century jazz music and musicians, positing the art form and its performers as “heterotopians”; simultaneously in and outside of the power relations of hegemonic time-space compression, travelling in an alternate...... and reactionary and suggests that the way time is employed in a heterotopic space determines its progressive potential. Spaces of accumulative, static, or frozen time refuse to yield any utopian promise, whereas fluid, dynamic, and ephemeral time offers moments of agency. In the case of Valaida, music...

  19. Emotion and Implicit Timing.

    Directory of Open Access Journals (Sweden)

    Sylvie Droit-Volet

    Full Text Available This study examined the effects of emotion on implicit timing. In the implicit timing task used, the participants did not receive any temporal instructions. Instead they were simply asked and trained to press a key as quickly as possible after a stimulus (response stimulus that was separated from a preceding stimulus by a given temporal interval (reference interval duration. However, in the testing phase, the interval duration was the reference interval duration or a shorter or longer interval duration. In addition, the participants attended two sessions: a first baseline session in which no stimulus was presented during the inter-stimulus intervals, and a second emotional session in which emotional facial expressions (angry, neutral and sad facial expressions were presented during these intervals. Results showed faster RTs for interval durations close to the reference duration in both the baseline and the emotional conditions and yielded a U-shaped curve. This suggests that implicit processing of time persists in emotional contexts. In addition, the RT was faster for the facial expressions of anger than for those of neutrality and sadness. However, the U-shaped RT curve did not peak clearly at a shorter interval duration for the angry than for the other facial expressions. This lack of time distortion in an implicit timing task in response to arousing emotional stimuli questions the idea of an automatic speeding-up of the interval clock system involved in the representation of time.

  20. Emotion and Implicit Timing.

    Science.gov (United States)

    Droit-Volet, Sylvie

    2016-01-01

    This study examined the effects of emotion on implicit timing. In the implicit timing task used, the participants did not receive any temporal instructions. Instead they were simply asked and trained to press a key as quickly as possible after a stimulus (response stimulus) that was separated from a preceding stimulus by a given temporal interval (reference interval duration). However, in the testing phase, the interval duration was the reference interval duration or a shorter or longer interval duration. In addition, the participants attended two sessions: a first baseline session in which no stimulus was presented during the inter-stimulus intervals, and a second emotional session in which emotional facial expressions (angry, neutral and sad facial expressions) were presented during these intervals. Results showed faster RTs for interval durations close to the reference duration in both the baseline and the emotional conditions and yielded a U-shaped curve. This suggests that implicit processing of time persists in emotional contexts. In addition, the RT was faster for the facial expressions of anger than for those of neutrality and sadness. However, the U-shaped RT curve did not peak clearly at a shorter interval duration for the angry than for the other facial expressions. This lack of time distortion in an implicit timing task in response to arousing emotional stimuli questions the idea of an automatic speeding-up of the interval clock system involved in the representation of time.

  1. Time dependent seismic hazard

    Science.gov (United States)

    Polidoro, B.; Iervolino, I.; Chioccarelli, E.; Giorgio, M.

    2012-04-01

    Probabilistic seismic hazard is usually computed trough a homogeneous Poisson process that even though it is a time-independent process it is widely used for its very convenient properties. However, when a single fault is of concern and/or the time scale is different from that of the long term, time-dependent processes are required. In this paper, different time-dependent models are reviewed with working examples. In fact, the Paganica fault (in central Italy) has been considered to compute both the probability of occurrence of at least one event in the lifespan of the structure, as well as the seismic hazard expressed in terms of probability of exceedance of an intensity value in a given time frame causing the collapse of the structure. Several models, well known or novel application to engineering hazard have been considered, limitation and issues in their applications are also discussed. The Brownian Passage Time (BPT) model is based on a stochastic modification of the deterministic stick-slip oscillator model for characteristic earthquakes; i.e., based on the addition of random perturbations (a Gaussian white noise) to the deterministic load path predicted by elastic rebound theory. This model assumes that the load state is at some ground level immediately after an event, increases steadly over time, reaches a failure threshold and relaxes instantaneously back to the ground level. For this model also a variable threshold has been considered to take into account the uncertainty of the threshold value. For the slip-predictable model it is assumed that the stress accumulates at a constant rate starting from some initial stress level. Stress is assumed to accumulate for a random period of time until an earthquake occurs. The size of the earthquake is governed by the stress release and it is a function of the elapsed time since the last event. In the time-predictable model stress buildup occurs at a constant rate until the accumulated stress reaches a threshold

  2. Quantitative real-time RT-PCR in sentinel lymph nodes from melanoma patients. Detection of melanocytic mRNA predicts disease-free survival

    DEFF Research Database (Denmark)

    Riber-Hansen, Rikke; Abrahamsen, Helene Nortvig; Sorensen, Boe Sandahl

    2008-01-01

    Quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR) for specific melanoma markers is more sensitive than histology for detecting cells of melanocytic origin in sentinel lymph nodes (SLNs) in cutaneous melanoma. The clinical significance of a positive qRT-PCR analysis...... is unclear. We performed qRT-PCR for the presence of MART-1 and tyrosinase in SLNs from 93 melanoma patients, and then followed these patients clinically (median follow-up time 43.5 months). We found a significant correlation between disease progression and presence of MART-1 mRNA in SLNs (p=0.......02), but no correlation with the amount of MART-1 mRNA as measured by qRT-PCR. No correlation between histology and recurrence was detected, recurrence rates being low in both histology-negative (12%) and -positive (15%) patients. We found a significant difference in disease recurrence between patients positive by both...

  3. Effect of the radiation intensity, water turbidity and exposure time on the survival of Cryptosporidium during simulated solar disinfection of drinking water.

    Science.gov (United States)

    Gómez-Couso, Hipólito; Fontán-Sainz, María; McGuigan, Kevin G; Ares-Mazás, Elvira

    2009-10-01

    The solar disinfection (SODIS) technique is a highly effective process that makes use of solar energy to inactivate pathogenic microorganisms in drinking water in developing countries. The pathogenic protozoan parasite Cryptosporidium parvum is often found in surface waters and is associated with waterborne outbreaks of cryptosporidiosis. In the present study, a complete multi-factorial mathematical model was used to investigate the combined effects of the intensity of solar radiation (200, 600 and 900W/m(2) in the 320nm to 10microm range), water turbidity (5, 100 and 300 NTU) and exposure time (4, 8 and 12h) on the viability and infectivity of C. parvum oocysts during simulated SODIS procedures at a constant temperature of 30 degrees C. All three factors had significant effects (p or =600W/m(2) and times of exposure between 8 and 12h were required to reduce the oocyst infectivity in water samples with different degrees of turbidity.

  4. SNS Diagnostics Timing Integration

    CERN Document Server

    Long, Cary D; Murphy, Darryl J; Pogge, James; Purcell, John D; Sundaram, Madhan

    2005-01-01

    The Spallation Neutron Source (SNS) accelerator systems will deliver a 1.0 GeV, 1.4 MW proton beam to a liquid mercury target for neutron scattering research. The accelerator complex consists of a 1 GeV linear accelerator, an accumulator ring and associated transport lines. The SNS diagnostics platform is PC-based running Windows XP Embedded for its OS and LabVIEW as its programming language. Coordinating timing among the various diagnostics instruments with the generation of the beam pulse is a challenging task that we have chosen to divide into three phases. First, timing was derived from VME based systems. In the second phase, described in this paper, timing pulses are generated by an in house designed PCI timing card installed in ten diagnostics PCs. Using fan-out modules, enough triggers were generated for all instruments. This paper describes how the Timing NAD (Network Attached Device) was rapidly developed using our NAD template, LabVIEW's PCI driver wizard, and LabVIEW Channel Access library. The NAD...

  5. Time travel a history

    CERN Document Server

    Gleick, James

    2016-01-01

    From the acclaimed author of The Information and Chaos, here is a mind-bending exploration of time travel: its subversive origins, its evolution in literature and science, and its influence on our understanding of time itself. The story begins at the turn of the previous century, with the young H. G. Wells writing and rewriting the fantastic tale that became his first book and an international sensation: The Time Machine. It was an era when a host of forces was converging to transmute the human understanding of time, some philosophical and some technological: the electric telegraph, the steam railroad, the discovery of buried civilizations, and the perfection of clocks. James Gleick tracks the evolution of time travel as an idea that becomes part of contemporary culture—from Marcel Proust to Doctor Who, from Jorge Luis Borges to Woody Allen. He investigates the inevitable looping paradoxes and examines the porous boundary between pulp fiction and modern physics. Finally, he delves into a temporal shift that...

  6. The Time of Materiality

    Directory of Open Access Journals (Sweden)

    Estrid Sørensen

    2007-01-01

    Full Text Available While time and space form a classic duality in social science, this article demonstrates a perspective on time, space and materiality as a core trinity. As a prominent figure in contemporary discussions on materiality in the social sciences Science and Technology Studies (STS emphasizes relational approaches. STS however lacks a clear relational definition of materiality and tends instead to focus on the agency of entities, on for instance material agency. The article suggests a relational definition of materiality and notes that this move implies turning the question of the time of materiality into an empirical question. It is argued that relational materiality must be studied spatially, and thus a spatial approach describing patterns of relations is presented. Based on field work in a primary school classroom and computer lab, three materials are analyzed: the blackboard, a bed-loft and an online 3D virtual environment. The empirical descriptions depict three different materialities, and it is shown how time is formed differently in each of them. Time, it is argued, is an emergent and characterizing aspect of materialities as spatial formations. URN: urn:nbn:de:0114-fqs070122

  7. Agency, time and causality

    Directory of Open Access Journals (Sweden)

    Thomas eWidlok

    2014-11-01

    Full Text Available Cognitive Scientists interested in causal cognition increasingly search for evidence from non-WEIRD people but find only very few cross-cultural studies that specifically target causal cognition. This article suggests how information about causality can be retrieved from ethnographic monographs, specifically from ethnographies that discuss agency and concepts of time. Many apparent cultural differences with regard to causal cognition dissolve when cultural extensions of agency and personhood to non-humans are taken into account. At the same time considerable variability remains when we include notions of time, linearity and sequence. The article focuses on ethnographic case studies from Africa but provides a more general perspective on the role of ethnography in research on the diversity and universality of causal cognition.

  8. Into the Wild Time

    DEFF Research Database (Denmark)

    Berg Johansen, Christina

    2017-01-01

    I want to feel the temporalities I am theorizing and writing about. To feel, explore, be moved through, tugged under by my research subject, to not know where my explorations will take me. How does time appear when I take responsibility for it instead of placing it as and with the Other? Can my...... temporal research emerge in symbiotic play with other human and non-human entities? In this essay, I will share how a methodological breakdown opened to me a net of (auto-)ethnographic wo/anderings, dialogical interviews and performative time-laboratories. I do not know where I am headed, but every...... sensuous memory lies in store, waiting for its time....

  9. Creating Space and Time

    DEFF Research Database (Denmark)

    Sandvik, Kjetil; Refslund Christensen, Dorthe

    This paper explores relations between ritualized spatiality and the conceptions of time reflected in memorial websites such as the Danish site Mindet.dk, a narrowly framed, socially protective online community in which individuals can perform their grief through design of individual entries...... (‘memories’) for their deceased loved ones and get personal, social support in their mourning processes through communication with other mourners, through mutual appreciation of each other’s postings and through emotional labor reflected on the individual sites. The main focus in this paper is how online...... referred to through accounts of ‘how death occurred’; second, a present time constituted by emotional and social stress and, thirdly, a wishful time or subjunctive mode articulating relational potentialities of these children and inventing memories with them (“I wish you would have lived to….”). We analyze...

  10. Accelerating time to benefit

    DEFF Research Database (Denmark)

    Svejvig, Per; Geraldi, Joana; Grex, Sara

    Despite the ubiquitous pressure for speed, our approaches to accelerate projects remain constrained to the old-fashioned understanding of the project as a vehicle to deliver products and services, not value. This article explores an attempt to accelerate time to benefit. We describe and deconstruct...... of the time. Although all cases valued speed and speed to benefit, and implemented most practices proposed by the methodology, only three of the five projects were more successful in decreasing time to speed. Based on a multi-case study comparison between these five different projects and their respective...... the implementation of a large intervention undertaken in five project-based organizations in Denmark – the Project Half Double where the same project methodology has been applied in five projects, each of them in five distinct organizations in Denmark, as a bold attempt to realize double the benefit in half...

  11. Time Domain Induced Polarization

    DEFF Research Database (Denmark)

    Fiandaca, Gianluca; Auken, Esben; Christiansen, Anders Vest

    2012-01-01

    Time-domain-induced polarization has significantly broadened its field of reference during the last decade, from mineral exploration to environmental geophysics, e.g., for clay and peat identification and landfill characterization. Though, insufficient modeling tools have hitherto limited the use......%. Furthermore, the presence of low-pass filters in time-domain-induced polarization instruments affects the early times of the acquired decays (typically up to 100 ms) and has to be modeled in the forward response to avoid significant loss of resolution. The developed forward code has been implemented in a 1D...... polarization response when compared to traditional integral chargeability inversion. The quality of the inversion results has been assessed by a complete uncertainty analysis of the model parameters; furthermore, borehole information confirm the outcomes of the field interpretations. With this new accurate...

  12. Drug Retention Times

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2007-05-01

    The purpose of this monograph is to provide information on drug retention times in the human body. The information provided is based on plausible illegal drug use activities that might be engaged in by a recreational drug user. Based on anecdotal evidence, most people “party” during extended time away from the work environment. Therefore, the following scenarios were envisioned: (1) a person uses an illicit drug at a party on Saturday night (infrequent user); (2) a person uses a drug one time on Friday night and once again on Saturday night (infrequent user); and (3) a person uses a drug on Friday night, uses a drug twice on Saturday night, and once again on Sunday (frequent user).

  13. Time Discretization Techniques

    KAUST Repository

    Gottlieb, S.

    2016-10-12

    The time discretization of hyperbolic partial differential equations is typically the evolution of a system of ordinary differential equations obtained by spatial discretization of the original problem. Methods for this time evolution include multistep, multistage, or multiderivative methods, as well as a combination of these approaches. The time step constraint is mainly a result of the absolute stability requirement, as well as additional conditions that mimic physical properties of the solution, such as positivity or total variation stability. These conditions may be required for stability when the solution develops shocks or sharp gradients. This chapter contains a review of some of the methods historically used for the evolution of hyperbolic PDEs, as well as cutting edge methods that are now commonly used.

  14. Probing human response times

    Science.gov (United States)

    Johansen, Anders

    2004-07-01

    In a recent preprint (Dialog in e-mail traffic, preprint cond-mat/0304433), the temporal dynamics of an e-mail network has been investigated by Eckmann, Moses and Sergi. Specifically, the time period between an e-mail message and its reply were recorded. It will be shown here that their data agrees quantitatively with the frame work proposed to explain a recent experiment on the response of “internauts” to a news publication (Physica A 296(3-4) (2001) 539) despite differences in communication channels, topics, time-scale and socio-economic characteristics of the two population. This suggest a generalized response time distribution ∼ t-1 for human populations in the absence of deadlines with important implications for psychological and social studies as well the study of dynamical networks.

  15. Potential factors affecting survival differ by run-timing and location: linear mixed-effects models of Pacific salmonids (Oncorhynchus spp. in the Klamath River, California.

    Directory of Open Access Journals (Sweden)

    Rebecca M Quiñones

    Full Text Available Understanding factors influencing survival of Pacific salmonids (Oncorhynchus spp. is essential to species conservation, because drivers of mortality can vary over multiple spatial and temporal scales. Although recent studies have evaluated the effects of climate, habitat quality, or resource management (e.g., hatchery operations on salmonid recruitment and survival, a failure to look at multiple factors simultaneously leaves open questions about the relative importance of different factors. We analyzed the relationship between ten factors and survival (1980-2007 of four populations of salmonids with distinct life histories from two adjacent watersheds (Salmon and Scott rivers in the Klamath River basin, California. The factors were ocean abundance, ocean harvest, hatchery releases, hatchery returns, Pacific Decadal Oscillation, North Pacific Gyre Oscillation, El Niño Southern Oscillation, snow depth, flow, and watershed disturbance. Permutation tests and linear mixed-effects models tested effects of factors on survival of each taxon. Potential factors affecting survival differed among taxa and between locations. Fall Chinook salmon O. tshawytscha survival trends appeared to be driven partially or entirely by hatchery practices. Trends in three taxa (Salmon River spring Chinook salmon, Scott River fall Chinook salmon; Salmon River summer steelhead trout O. mykiss were also likely driven by factors subject to climatic forcing (ocean abundance, summer flow. Our findings underscore the importance of multiple factors in simultaneously driving population trends in widespread species such as anadromous salmonids. They also show that the suite of factors may differ among different taxa in the same location as well as among populations of the same taxa in different watersheds. In the Klamath basin, hatchery practices need to be reevaluated to protect wild salmonids.

  16. Relational time in physics

    Energy Technology Data Exchange (ETDEWEB)

    Assis, A.K.T. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil)

    2011-07-01

    Full text: Isaac Newton (1642-1727) defended in his book Mathematical Principles of Natural Philosophy, also know as Principia, published in 1687, the utilization of absolute time in physics. According to him 'absolute, true, and mathematical time, of itself, and from its own nature, flows equably without relation to anything external'. Leibniz (1646-1716), on the other hand, was against this concept and proposed relative time to replace it: 'As for my opinion, I have said more than once, that I hold space to be something merely relative, as time is; that I hold it to be an order of coexistence, as time is an order of successions'. Leibniz ideas were accepted and developed by Ernst Mach (1838-1916) in his book The Science of Mechanics, published in 1883. In this work we consider the implementation of relational time, as proposed by Leibniz and Mach, and the consequences this implementation will mean for physics as a whole. We consider some specific examples related to mechanics (Newton's bucket experiment, the flattening of the Earth, Foucault's pendulum experiment) and to electromagnetism (Ampere's force between current carrying wires, an electric charge describing a Larmor radius due to a nearby large magnet, two charges orbiting around one another). We generalize these ideas considering the principle of physical proportions (PPP), according to which no absolute magnitudes should appear in the laws of physics. We present some laws satisfying this principle and others which do not comply with it. The laws which do not satisfy the PPP should be based upon incomplete theories. We present the consequences of complete theories complying with this fundamental principle of nature. (author)

  17. Time series analysis

    CERN Document Server

    Madsen, Henrik

    2007-01-01

    ""In this book the author gives a detailed account of estimation, identification methodologies for univariate and multivariate stationary time-series models. The interesting aspect of this introductory book is that it contains several real data sets and the author made an effort to explain and motivate the methodology with real data. … this introductory book will be interesting and useful not only to undergraduate students in the UK universities but also to statisticians who are keen to learn time-series techniques and keen to apply them. I have no hesitation in recommending the book.""-Journa

  18. Applied time series analysis

    CERN Document Server

    Woodward, Wayne A; Elliott, Alan C

    2011-01-01

    ""There is scarcely a standard technique that the reader will find left out … this book is highly recommended for those requiring a ready introduction to applicable methods in time series and serves as a useful resource for pedagogical purposes.""-International Statistical Review (2014), 82""Current time series theory for practice is well summarized in this book.""-Emmanuel Parzen, Texas A&M University""What an extraordinary range of topics covered, all very insightfully. I like [the authors'] innovations very much, such as the AR factor table.""-David Findley, U.S. Census Bureau (retired)""…

  19. Science of Time

    Science.gov (United States)

    Vedavyas

    A Multi-disciplinary Research into the Chronologies of Ancient Nations -- like the Vedas of India Rishies, the Chaldeans, Babylonians, Egyptians and the Chinese. Which traces how the "Measurement of Time" -- which began with the observations of sunrise and Sunset, Full-Moons, eclipses, the movement of stars and the Discovery of the Zodiac that starry pathway of sun in his annual Cycle of the 12-Zodiacal months, the Measurement of Time by planetary Cycles the Discovery of Astronomy and Symbolic or Kabalistic Astrology of the Bible's Old Testament; the Epics of Babylonians and 'Cosmic Cycles' of Chaldeans and Egyptians also the Ancient "Four Yugas" or Hindu Vedic Cycles.

  20. general dispatching time

    Directory of Open Access Journals (Sweden)

    Ho Woo Lee

    2000-01-01

    Full Text Available In this paper, we analyze a production system with a finite feedback buffer and dispatching time. Parts enter a “main buffer” before they are processed. Processed parts leave the system with probability 1−p or are fed back to a “feedback buffer” with probability p. As soon as the feedback buffer becomes full, the parts in the feedback buffer are dispatched, all at once, to the main buffer by the server for reprocessing. The dispatching time follows a general distribution. Thus the server is engaged either in one of the following states: idle, processing, dispatching.

  1. Time and Logic

    DEFF Research Database (Denmark)

    Øhrstrøm, Peter

    2009-01-01

    This paper deals with A.N. Prior's analysis of the concepts of dynamic and static time, i.e. McTaggart's so-called A- and B-concepts. The relations and mutual dependencies between these temporal concepts are investigated, and Prior's response to McTaggart's views is discussed. Futhermore, Prior......'s notion of branching time is analysed. It is argued that Prior can be criticized for identifying 'plain future'. Finally, Prior's four grades of tense-logical involvement are introduced and discussed. It is argued that the third grade is the most attractive form a philosophical point of view....

  2. Correlation of [11C]choline PET-CT with time to treatment and disease-specific survival in men with recurrent prostate cancer after radical prostatectomy

    NARCIS (Netherlands)

    Breeuwsma, A.J.; Rybalov, M; Leliveld, AM; Pruim, J; de Jong, Igle Jan

    2012-01-01

    Aim: Radiotherapy following radical prostatectomy should be considered in men with high risk features who have a life expectancy of more than 10 years. So far no effect on prostate cancer specific survival has been proven by 3 randomized controlled trials (RCTs) on adjuvant radiotherapy. At present

  3. Long-Term Survival of Dental Implants with Different Prosthetic Loading Times in Healthy Patients: A 5-Year Retrospective Clinical Study.

    Science.gov (United States)

    Muelas-Jiménez, M Isabel; Olmedo-Gaya, Maria Victoria; Manzano-Moreno, Francisco J; Reyes-Botella, Candela; Vallecillo-Capilla, Manuel

    2017-02-01

    To compare survival rates among dental implants restored with immediate, early, and conventional loading protocols, also comparing between maxillary and mandibular implants, and to evaluate the influence of implant length and diameter and the type of prosthesis on treatment outcomes. This retrospective cohort study initially included all 52 patients receiving dental implants between July 2006 and February 2008 at a private oral surgery clinic in Granada (Southern Spain). Clinical and radiographic examinations were performed, including periapical or panoramic radiographs, and incidences during completion of the restoration were recorded at 1 week, 3 months, 6 months, and at 1, 2, 3, 4, and 5 years. After a 5-year follow-up, 1 patient had died, 3 were lost to follow-up, and 6 required grafting before implant placement; therefore, the final study sample comprised 42 patients with 164 implants. Variables associated with the survival/failure of the restoration were: number of implants (higher failure rate with fewer implants), bone type (higher failure rate in type III or IV bone), and type of prosthesis (higher failure rate with single crowns). No significant association was found in univariate or multivariate analyses between survival rate and the loading protocol, implant length or diameter, or maxillary/mandibular location. Immediate occlusal loading, immediate provisionalization without occlusal loading, and early loading are viable treatment options with similar survival rates to those obtained with conventional loading. Bone quality and number of implants per patient were the most influential factors. © 2015 by the American College of Prosthodontists.

  4. Time for Reading?

    Science.gov (United States)

    Fowler, William R.

    1989-01-01

    Reading for pleasure and enlightenment is a critical, and endangered, element in a well-informed citizenry. As a basis for intellectual growth, reading is threatened by media misuse and lack of encouragement of recreational reading. Solutions include emphasis on integrated skills, improved time allocation, and cooperation among parents, teachers,…

  5. DELPHI time projection chamber

    CERN Multimedia

    1989-01-01

    The time projection chamber is inserted inside the central detector of the DELPHI experiment. Gas is ionised in the chamber as a charged particle passes through, producing an electric signal from which the path of the particle can be found. DELPHI, which ran from 1989 to 2000 on the LEP accelerator, was primarily concerned with particle identification.

  6. Swinging in Imaginary Time

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 2. Swinging in Imaginary Time - More on the Not-So-Simple Pendulum. Cihan Saclioglu. General Article Volume 15 Issue 2 February 2010 pp 104-115. Fulltext. Click here to view fulltext PDF. Permanent link:

  7. Improving Hospital Discharge Time

    Science.gov (United States)

    El-Eid, Ghada R.; Kaddoum, Roland; Tamim, Hani; Hitti, Eveline A.

    2015-01-01

    Abstract Delays in discharging patients can impact hospital and emergency department (ED) throughput. The discharge process is complex and involves setting specific challenges that limit generalizability of solutions. The aim of this study was to assess the effectiveness of using Six Sigma methods to improve the patient discharge process. This is a quantitative pre and post-intervention study. Three hundred and eighty-six bed tertiary care hospital. A series of Six Sigma driven interventions over a 10-month period. The primary outcome was discharge time (time from discharge order to patient leaving the room). Secondary outcome measures included percent of patients whose discharge order was written before noon, percent of patients leaving the room by noon, hospital length of stay (LOS), and LOS of admitted ED patients. Discharge time decreased by 22.7% from 2.2 hours during the preintervention period to 1.7 hours post-intervention (P discharge. Hospital LOS dropped from 3.4 to 3.1 days postintervention (P hospital was significantly lower in the postintervention period (6.9 ± 7.8 vs 5.9 ± 7.7 hours; P discharge time. The focus of institutions aspiring to tackle delays in the discharge process should be on adopting the core principles of Six Sigma rather than specific interventions that may be institution-specific. PMID:25816029

  8. The SIM Time Network.

    Science.gov (United States)

    Lombardi, Michael A; Novick, Andrew N; Lopez R, J Mauricio; Jimenez, Francisco; de Carlos Lopez, Eduardo; Boulanger, Jean-Simon; Pelletier, Raymond; de Carvalho, Ricardo J; Solis, Raul; Sanchez, Harold; Quevedo, Carlos Andres; Pascoe, Gregory; Perez, Daniel; Bances, Eduardo; Trigo, Leonardo; Masi, Victor; Postigo, Henry; Questelles, Anthony; Gittens, Anselm

    2011-01-01

    The Sistema Interamericano de Metrologia (SIM) is a regional metrology organization (RMO) whose members are the national metrology institutes (NMIs) located in the 34 nations of the Organization of American States (OAS). The SIM/OAS region extends throughout North, Central, and South America and the Caribbean Islands. About half of the SIM NMIs maintain national standards of time and frequency and must participate in international comparisons in order to establish metrological traceability to the International System (SI) of units. The SIM time network (SIMTN) was developed as a practical, cost effective, and technically sound way to automate these comparisons. The SIMTN continuously compares the time standards of SIM NMIs and produces measurement results in near real-time by utilizing the Internet and the Global Positioning System (GPS). Fifteen SIM NMIs have joined the network as of December 2010. This paper provides a brief overview of SIM and a technical description of the SIMTN. It presents international comparison results and examines the measurement uncertainties. It also discusses the metrological benefits that the network provides to its participants.

  9. Visual time series analysis

    DEFF Research Database (Denmark)

    Fischer, Paul; Hilbert, Astrid

    2012-01-01

    commands, our application is select-and-click-driven. It allows to derive many different sequences of deviations for a given time series and to visualize them in different ways in order to judge their expressive power and to reuse the procedure found. For many transformations or model-ts, the user may...

  10. Reflections on time

    Science.gov (United States)

    Swist, Fred

    2012-08-01

    The ArcheTime conference was completely unlike most meetings attended by physicists. Organized by conceptual artist Olga Ast, the June 2009 event brought together more than 70 people from a wide range of backgrounds, including artists, philosophers, writers, photographers and filmmakers as well as scientists.

  11. Space, Time and Relativity

    Indian Academy of Sciences (India)

    Special Relativity is now a hundred years old, and Gen- eral Relativity is just ten years younger. Even the gen- eral literate public probably knows that these two the- ories of physics - STR and GTR - profoundly altered previous conceptions and understanding of space and time in physics. We will try to describe these ...

  12. Smartphones and Time Zones

    Science.gov (United States)

    Baird, William; Secrest, Jeffery; Padgett, Clifford; Johnson, Wayne; Hagrelius, Claire

    2016-01-01

    Using the Sun to tell time is an ancient idea, but we can take advantage of modern technology to bring it into the 21st century for students in astronomy, physics, or physical science classes. We have employed smartphones, Google Earth, and 3D printing to find the moment of local noon at two widely separated locations. By reviewing GPS…

  13. Falling out of time

    DEFF Research Database (Denmark)

    Oldrup, Helene

    2017-01-01

    on data from a Danish study of mothers and children, aged 5–27, whose father/stepfather was incarcerated. Findings show the significance of a multifaceted understanding of time showing the implications of fathers’ imprisonment for children, suggesting that policy initiatives would be enriched by a focus...

  14. Equal Time for Women.

    Science.gov (United States)

    Kolata, Gina

    1984-01-01

    Examines social influences which discourage women from pursuing studies in computer science, including monopoly of computer time by boys at the high school level, sexual harassment in college, movies, and computer games. Describes some initial efforts to encourage females of all ages to study computer science. (JM)

  15. Good Times in Tiibingen

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 8. Good Times in Tübingen. Wolfgang Engelmann. Book Review Volume 11 Issue 8 August 2006 pp 101-102. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/011/08/0101-0102. Author Affiliations.

  16. Travel time reliability modeling.

    Science.gov (United States)

    2011-07-01

    This report includes three papers as follows: : 1. Guo F., Rakha H., and Park S. (2010), "A Multi-state Travel Time Reliability Model," : Transportation Research Record: Journal of the Transportation Research Board, n 2188, : pp. 46-54. : 2. Park S.,...

  17. Video time encoding machines.

    Science.gov (United States)

    Lazar, Aurel A; Pnevmatikakis, Eftychios A

    2011-03-01

    We investigate architectures for time encoding and time decoding of visual stimuli such as natural and synthetic video streams (movies, animation). The architecture for time encoding is akin to models of the early visual system. It consists of a bank of filters in cascade with single-input multi-output neural circuits. Neuron firing is based on either a threshold-and-fire or an integrate-and-fire spiking mechanism with feedback. We show that analog information is represented by the neural circuits as projections on a set of band-limited functions determined by the spike sequence. Under Nyquist-type and frame conditions, the encoded signal can be recovered from these projections with arbitrary precision. For the video time encoding machine architecture, we demonstrate that band-limited video streams of finite energy can be faithfully recovered from the spike trains and provide a stable algorithm for perfect recovery. The key condition for recovery calls for the number of neurons in the population to be above a threshold value.

  18. On Space and Time

    Science.gov (United States)

    Majid, Shahn; Polkinghorne, With contributions by John; Penrose, Roger; Taylor, Andrew; Connes, Alain; Heller, Michael

    2012-03-01

    Preface; 1. The dark universe A. N. Taylor; 2. Quantum spacetime and physical reality S. Majid; 3. Causality, quantum theory and cosmology R. Penrose; 4. On the fine structure of spacetime A. Connes; 5. Where physics meets metaphysics M. Heller; 6. The nature of time J. C. Polkinghorne; Index.

  19. "Time" in China.

    Science.gov (United States)

    Weland, James E.

    1982-01-01

    Discusses how the Chinese have recorded their history by dynasties, the length of time any one imperial clan could retain its hold on the Dragon Throne. Dynastic histories were used to instruct rulers in the ways ethical problems of government had been dealt with in the past. (AM)

  20. Space-time structure

    CERN Document Server

    Schrödinger, Erwin

    1985-01-01

    In response to repeated requests this classic book on space-time structure by Professor Erwin Schrödinger is now available in the Cambridge Science Classics series. First published in 1950, and reprinted in 1954 and 1960, this lucid and profound exposition of Einstein's 1915 theory of gravitation still provides valuable reading for students and research workers in the field.

  1. Fontan Circulation over Time

    NARCIS (Netherlands)

    Wolff, Djoeke; van Melle, Joost P.; Bartelds, Beatrijs; Ridderbos, Floris-Jan S.; Eshuis, Graziella; van Stratum, Elisabeth B. H. J.; Recinos, Salvador J.; Willemse, Brigitte W. M.; Hillege, Hans; Willems, Tineke P.; Ebels, Tjark; Berger, Rolf M. F.

    2017-01-01

    The unique, unphysiological Fontan circulation is associated with an impaired functional status of the patients that is suggested to deteriorate over time. Unfortunately, previous studies did not integrate both pulmonary and cardiac determinants of functional status. In addition, a comparison with

  2. The dance of time

    CERN Document Server

    Aparici, Irene; Brokenbrow, Jon

    2014-01-01

    Winner at the 2014 Living Now Book Awards The Dance of Time is a book full of imagination and information, which will be useful for parents and teachers looking to accompany children on a different kind of journey through our solar system. Guided Reading Level: P, Lexile Level: 830L.

  3. Time reversal communication system

    Science.gov (United States)

    Candy, James V.; Meyer, Alan W.

    2008-12-02

    A system of transmitting a signal through a channel medium comprises digitizing the signal, time-reversing the digitized signal, and transmitting the signal through the channel medium. The channel medium may be air, earth, water, tissue, metal, and/or non-metal.

  4. Survival of time-evolved quantum correlations depending on whether quenching is across a critical point in an X Y spin chain

    Science.gov (United States)

    Mishra, Utkarsh; Rakshit, Debraj; Prabhu, R.

    2016-04-01

    The time dynamics of quantum correlations in the quantum transverse anisotropic X Y spin chain of infinite length is studied at zero and finite temperatures. The evolution occurs due to the instantaneous quenching of the coupling constant between the nearest-neighbor spins of the model, which is performed either within the same phase or across the quantum phase-transition point connecting the order-disorder phases of the model. We characterize the time-evolved quantum correlations, viz., entanglement and quantum discord, which exhibit varying behavior depending on the initial state and the quenching scheme. We show that the system is endowed with enhanced nearest-neighbor bipartite quantum correlations compared to that of the initial state, when quenched from the ordered to the deep disordered phase. However, nearest-neighbor quantum correlations are almost washed out when the system is quenched from the disordered to the ordered phase with the initial state being at the zero temperature. We also identify the condition for the occurrence of enhanced bipartite correlations when the system is quenched within the same phase. Moreover, we investigate the bipartite quantum correlations when the initial state is a thermal equilibrium state with finite temperature, which reveals the effects of thermal fluctuation on the phenomena observed at zero temperature. Finally, an analogous analysis is carried out for zero-temperature next-nearest-neighbor quantum correlations.

  5. Time and Measurement Days

    Science.gov (United States)

    Scargle, Jeffrey D.

    2017-01-01

    Questions in data analysis involving the concepts of time and measurement are often pushed into the background or reserved for a philosophical discussion. Some examples are: a) Is causality a consequence of the laws of physics, or can the arrow of time be reversed? b) Can we determine the arrow of time of an event? c) Do we need the continuum hypothesis for the underlying function in any measurement process? d) Can we say anything about the analyticity of the underlying process of an event? e) Would it be valid to model a non-analytical process as function of time? f) What are the implications of all these questions for classical Fourier techniques? However, in the age of big data gathered either from space missions supplying ultra-precise long time series, or e.g. LIGO data from the ground, the moment to bring these questions to the foreground seems arrived. The limitations of our understanding of some fundamental processes is emphasized by the lack of solution for problems open for more than 2 decades, such as the non-detection of solar g-modes, or the modal identification of main sequence stellar pulsators like delta Scuti stars. Flicker noise or 1/f noise, for example, attributed in solar-like stars to granulation, is analyzed mostly only to apply noise reduction techniques, neither considering the classical problem of 1/f noise that was introduced a 100 years ago, nor taking into account ergodic or non-ergodic solutions that make inapplicable spectral analysis techniques in practice. This topic was discussed by Nicholas W. Watkins during the ITISE meeting held in Granada in 2016. There he presented preliminary results of his research on Mandelbrot's related work. We reproduce here his quotation of Mandelbrot (1999) "There is a sharp contrast between a highly anomalous ("non-white") noise that proceeds in ordinary clock time and a noise whose principal anomaly is that it is restricted to fractal time", suggesting a connection with the above proposed topics that

  6. Stop wasting valuable time.

    Science.gov (United States)

    Mankins, Michael C

    2004-09-01

    Companies routinely squander their most precious resource--the time of their top executives. In the typical company, senior executives meet to discuss strategy for only three hours a month. And that time is poorly spent in diffuse discussions never even meant to result in any decision. The price of misused executive time is high. Delayed strategic decisions lead to overlooked waste and high costs, harmful cost reductions, missed new product and business development opportunities, and poor long-term investments. But a few deceptively simple changes in the way top management teams set agendas and structure team meetings can make an enormous difference in their effectiveness. Efficient companies use seven techniques to make the most of the time their top executives spend together. They keep strategy meetings separate from meetings focused on operations. They explore issues through written communications before they meet, so that meeting time is used solely for reaching decisions. In setting agendas, they rank the importance of each item according to its potential to create value for the company. They seek to get issues not only on, but also off, the agenda quickly, keeping to a clear implementation timetable. They make sure they have considered all viable alternatives before deciding a course of action. They use a common language and methodology for reaching decisions. And they insist that, once a decision is made, they stick to it--that there be no more debate or mere grudging compliance. Once leadership teams get the basics right, they can make more fundamental changes in the way they work together. Strategy making can be transformed from a series of fragmented and unproductive events into a streamlined, effective, and continuing management dialogue. In companies that have done this, management meetings aren't a necessary evil; they're a source of real competitive advantage.

  7. Time processing in dyscalculia

    Directory of Open Access Journals (Sweden)

    marinella eCappelletti

    2011-12-01

    Full Text Available To test whether atypical number development may affect other types of quantity processing, we investigated temporal discrimination in adults with developmental dyscalculia (DD. This also allowed us to test whether (1 number and time may be sub-served by a common quantity system or decision mechanisms –in which case they may both be impaired, or (2 whether number and time are distinct –and therefore they may dissociate. Participants judged which of two successively presented horizontal lines was longer in duration, the first line being preceded by either a small or a large number prime (‘1’ or ‘9’ or by a neutral symbol (‘#’, or in third task decide which of two Arabic numbers (either ‘1’, ‘5’, ’9’ lasted longer. Results showed that (i DD’s temporal discriminability was normal as long as numbers were not part of the experimental design even as task-irrelevant stimuli; however (ii task-irrelevant numbers dramatically disrupted DD’s temporal discriminability, the more their salience increased, though the actual magnitude of the numbers had no effect; and in contrast (iii controls’ time perception was robust to the presence of numbers but modulated by numerical quantity such that small number primes or numerical stimuli made durations appear shorter than veridical and the opposite for larger numerical prime or numerical stimuli. This study is the first to investigate continuous quantity as time in a population with a congenital number impairment and to show that atypical development of numerical competence leaves continuous quantity processing spared. Our data support the idea of a partially shared quantity system across numerical and temporal dimensions, which allows dissociations and interactions among dimensions; furthermore, they suggest that impaired number in DD is unlikely to originate from systems initially dedicated to continuous quantity processing like time.

  8. Averaging Satellite Timing Data for National and International Time Coordination

    National Research Council Canada - National Science Library

    Levine, Judah

    2005-01-01

    The International Bureau of Weights and Measures "BIPM" calculates International Atomic Time "TAI" and Coordinated Universal Time "UTC" using data from many national metrology institutes and timing laboratories...

  9. Immortal time bias in pharmacoepidemiological studies on cancer patient survival: empirical illustration for beta-blocker use in four cancers with different prognosis.

    Science.gov (United States)

    Weberpals, Janick; Jansen, Lina; van Herk-Sukel, Myrthe P P; Kuiper, Josephina G; Aarts, Mieke J; Vissers, Pauline A J; Brenner, Hermann

    2017-11-01

    Immortal time bias (ITB) is still seen frequently in medical literature. However, not much is known about this bias in the field of cancer (pharmaco-)epidemiology. In context of a hypothetical beneficial beta-blocker use among cancer patients, we aimed to demonstrate the magnitude of ITB among 9876 prostate, colorectal, lung and pancreatic cancer patients diagnosed between 1998 and 2011, which were selected from a database linkage of the Netherlands Cancer Registry and the PHARMO Database Network. Hazard ratios (HR) and 95% confidence intervals from three ITB scenarios, defining exposure at a defined point after diagnosis (model 1), at any point after diagnosis (model 2) and as multiple exposures after diagnosis (model 3), were calculated to investigate the association between beta-blockers and cancer prognosis using Cox proportional hazards regression. Results were compared to unbiased estimates derived from the Mantel-Byar model. Ignoring ITB led to substantial smaller HRs for beta-blocker use proposing a significant protective association in all cancer types [e.g. HR 0.18 (0.07-0.43) for pancreatic cancer in model 1], whereas estimates derived from the Mantel-Byar model were mainly suggesting no association [e.g. HR 1.10 (0.84-1.44)]. The magnitude of bias was consistently larger among cancer types with worse prognosis [overall median HR differences between all scenarios in model 1 and Mantel-Byar model of 0.56 (prostate), 0.72 (colorectal), 0.77 (lung) and 0.85 (pancreas)]. In conclusion, ITB led to spurious beneficial associations of beta-blocker use among cancer patients. The magnitude of ITB depends on the duration of excluded immortal time and the prognosis of each cancer.

  10. Tracking change over time

    Science.gov (United States)

    ,

    2011-01-01

    Landsat satellites capture images of Earth from space-and have since 1972! These images provide a long-term record of natural and human-induced changes on the global landscape. Comparing images from multiple years reveals slow and subtle changes as well as rapid and devastating ones. Landsat images are available over the Internet at no charge. Using the free software MultiSpec, students can track changes to the landscape over time-just like remote sensing scientists do! The objective of the Tracking Change Over Time lesson plan is to get students excited about studying the changing Earth. Intended for students in grades 5-8, the lesson plan is flexible and may be used as a student self-guided tutorial or as a teacher-led class lesson. Enhance students' learning of geography, map reading, earth science, and problem solving by seeing landscape changes from space.

  11. Student progression on time

    DEFF Research Database (Denmark)

    Sarauw, Laura Louise

    The paper discusses and problematizes the ways, in which recent Danish university reform challenges the ideals of the ‘Nordic model’. The aim of the so-called ‘speed-up’ reform (in Danish ‘studiefremdriftsreformen’) is to cut the time available for students to complete their university studies...... of the Bologna process. As a consequence of the reform, however, students in Denmark can no longer chose not to transfer credits outside of her main program. At the same time the existing requirements for supplying courses to enroll on a MA in a different subject area will be abolished. In total, the reform...... access and social mobility? The paper sets out from a mixed constructivist approach to policy that aims at exploring different empirical levels. In line with new constructivist theories of policy it is argued that reforms such as the speed up reform is a continuous contestation that must be studied...

  12. Optimising Lecture Time

    DEFF Research Database (Denmark)

    Holst-Christensen, Bo

    the students more actively in choosing teaching techniques - on a day to day basis. The result is that I now have more active students, that help me to ensure that they get the information and help they need. This also results in a much more efficient use of the time we spend together.......This paper presents the results of using different teaching techniques I have been experimenting with when teaching practice oriented subjects to Enginering students at the Technical University of Denmark. The primary problem I have encountered is that although students - as a rule - have a keen...... interest in getting a degree, they prefer the educators to do the work for them. The focus of my experiments have therefore been to develop teaching techniques that ensures that the students study efficiently and at the same time moves the task of identifying which parts of the subjects that are giving...

  13. Real Time Processing

    CERN Multimedia

    CERN. Geneva; ANDERSON, Dustin James; DOGLIONI, Caterina

    2015-01-01

    The LHC provides experiments with an unprecedented amount of data. Experimental collaborations need to meet storage and computing requirements for the analysis of this data: this is often a limiting factor in the physics program that would be achievable if the whole dataset could be analysed. In this talk, I will describe the strategies adopted by the LHCb, CMS and ATLAS collaborations to overcome these limitations and make the most of LHC data: data parking, data scouting, and real-time analysis.

  14. Gravity, Time, and Lagrangians

    Science.gov (United States)

    Huggins, Elisha

    2010-01-01

    Feynman mentioned to us that he understood a topic in physics if he could explain it to a college freshman, a high school student, or a dinner guest. Here we will discuss two topics that took us a while to get to that level. One is the relationship between gravity and time. The other is the minus sign that appears in the Lagrangian. (Why would one…

  15. Strange science takes time

    CERN Multimedia

    2008-01-01

    The late astronomer Carl Sagan popularized the saying that "extraordinary claims require extraordinary evidence," in reference to reports of alien visitations. Generating low-cost commercial fusion power, isolating antimatter and tracing reverse-time causality aren't as far out there as UFOs, but a similar rule might well apply: Extraordinary science requires extraordinary effort. With that in mind, here's a progress report on three extraordinary science projects that have popped up in the news...

  16. Time and human knowledge

    OpenAIRE

    Prigogine, I.

    1985-01-01

    The conflicting views of time proposed by nineteenth century classical science on the one hand and by biological and cultural evolution on the other are examined in the light of recent discoveries concerning nonequilibrium systems. A new view emerges of the evolution of complex systems, one where determinism and chance both play important roles, and where man begins to find his real place in a creative universe.

  17. Time to move on?

    CERN Document Server

    Ellis, John

    2017-01-01

    Cosmology and particle physics have long been dominated by theoretical paradigms: Einstein's general theory of relativity in cosmology and the Standard Model of particle physics. The time may have come for paradigm shifts. Does cosmological inflation require a modification of Einstein's gravity? Have experiments at the LHC discovered a new particle beyond the Standard Model? It is premature to answer these questions, but we theorists can dream about the possibilities.

  18. Real Time Baseball Database

    Science.gov (United States)

    Fukue, Yasuhiro

    The author describes the system outline, features and operations of "Nikkan Sports Realtime Basaball Database" which was developed and operated by Nikkan Sports Shimbun, K. K. The system enables to input numerical data of professional baseball games as they proceed simultaneously, and execute data updating at realtime, just-in-time. Other than serving as supporting tool for prepareing newspapers it is also available for broadcasting media, general users through NTT dial Q2 and others.

  19. Deep Time Contagion

    Directory of Open Access Journals (Sweden)

    Andy Weir

    2012-11-01

    Full Text Available An artist from London researching the effects of deprioritised subjectivity and contemporary art, Weir presents acoustic recordings made in deep geological repository sites. Repurposing these sites from their typical use as storage space for nuclear waste, Weir addresses the extra-human scale of Deep Time through sonic-fiction. Inhumanly enduring and impinging upon humanity largely imperceptibly, what agency—at what scale—is present?

  20. Discrete-Time Systems

    Indian Academy of Sciences (India)

    net immigrants entering the country in year k. We leave it to the reader to model the vacillating mathe- matician problem [3] as a discrete-time system. General Forms of Difference Equations. An nth order difference equation may be written, typically, either as y(k + n) + an-l y(k + n - 1) + + aO y(k) = bm u(k + m) + bm-l u(k + m ...

  1. Time at the beginning

    Energy Technology Data Exchange (ETDEWEB)

    Michael S. Turner

    2002-10-11

    Age consistency for the Universe today has been an important cosmological test. Even more powerful consistency tests at times as early as 10{sup -32} sec lie ahead in the precision era of cosmology. I outline tests based upon cosmic microwave background (CMB) anisotropy, big-bang nucleosynthesis (BBN), particle dark matter, phase transitions, and inflation. The ultimate cosmic timescale--the fate of the Universe--will be in doubt until the mystery of the dark energy is unraveled.

  2. Music in Galileo's Time

    Science.gov (United States)

    Petrobelli, P.

    2011-06-01

    Claudio Monteverdi appears as the key personality of the music in Galileo's time. His revolution in format and function of the musical language-from an essentially edonistic creation of purely sonorous images to a musical language consciously "expressive" of the content of the words on which it is based-is similar in character to the influential innovations in scientific thinking operated by Galileo.

  3. Time processing in dyscalculia.

    Science.gov (United States)

    Cappelletti, Marinella; Freeman, Elliot D; Butterworth, Brian L

    2011-01-01

    To test whether atypical number development may affect other types of quantity processing, we investigated temporal discrimination in adults with developmental dyscalculia (DD). This also allowed us to test whether number and time may be sub-served by a common quantity system or decision mechanisms: if they do, both should be impaired in dyscalculia, but if number and time are distinct they should dissociate. Participants judged which of two successively presented horizontal lines was longer in duration, the first line being preceded by either a small or a large number prime ("1" or "9") or by a neutral symbol ("#"), or in a third task participants decided which of two Arabic numbers (either "1," "5," "9") lasted longer. Results showed that (i) DD's temporal discriminability was normal as long as numbers were not part of the experimental design, even as task-irrelevant stimuli; however (ii) task-irrelevant numbers dramatically disrupted DD's temporal discriminability the more their salience increased, though the actual magnitude of the numbers had no effect; in contrast (iii) controls' time perception was robust to the presence of numbers but modulated by numerical quantity: therefore small number primes or numerical stimuli seemed to make durations appear shorter than veridical, but longer for larger numerical prime or numerical stimuli. This study is the first to show spared temporal discrimination - a dimension of continuous quantity - in a population with a congenital number impairment. Our data reinforce the idea of a partially shared quantity system across numerical and temporal dimensions, which supports both dissociations and interactions among dimensions; however, they suggest that impaired number in DD is unlikely to originate from systems initially dedicated to continuous quantity processing like time.

  4. Timing Foreign Exchange Markets

    Directory of Open Access Journals (Sweden)

    Samuel W. Malone

    2016-03-01

    Full Text Available To improve short-horizon exchange rate forecasts, we employ foreign exchange market risk factors as fundamentals, and Bayesian treed Gaussian process (BTGP models to handle non-linear, time-varying relationships between these fundamentals and exchange rates. Forecasts from the BTGP model conditional on the carry and dollar factors dominate random walk forecasts on accuracy and economic criteria in the Meese-Rogoff setting. Superior market timing ability for large moves, more than directional accuracy, drives the BTGP’s success. We explain how, through a model averaging Monte Carlo scheme, the BTGP is able to simultaneously exploit smoothness and rough breaks in between-variable dynamics. Either feature in isolation is unable to consistently outperform benchmarks throughout the full span of time in our forecasting exercises. Trading strategies based on ex ante BTGP forecasts deliver the highest out-of-sample risk-adjusted returns for the median currency, as well as for both predictable, traded risk factors.

  5. Time Reversal Violation

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, H; /SLAC

    2009-01-27

    This talk briefly reviews three types of time-asymmetry in physics, which I classify as universal, macroscopic and microscopic. Most of the talk is focused on the latter, namely the violation of T-reversal invariance in particle physics theories. In sum tests of microscopic T-invariance, or observations of its violation, are limited by the fact that, while we can measure many processes, only in very few cases can we construct a matched pair of process and inverse process and observe it with sufficient sensitivity to make a test. In both the cases discussed here we can achieve an observable T violation making use of flavor tagging, and in the second case also using the quantum properties of an antisymmetric coherent state of two B mesons to construct a CP-tag. Both these tagging properties depend only on very general properties of the flavor and/or CP quantum numbers and so provide model independent tests for T-invariance violations. The microscopic laws of physics are very close to T-symmetric. There are small effects that give CP- and T-violating processes in three-generation-probing weak decays. Where a T-violating observable can be constructed we see the relationships between T-violation and CP-violation expected in a CPT conserving theory. These microscopic effects are unrelated to the 'arrow of time' that is defined by increasing entropy, or in the time direction defined by the expansion of our Universe.

  6. Commission 31: Time

    Science.gov (United States)

    Matsakis, Demetrios; Defraigne, Pascale; Hosokawa, M.; Leschiutta, S.; Petit, G.; Zhai, Z.-C.

    2007-03-01

    The most intensely discussed and controversial issue in time keeping has been the proposal before the International Telecommunications Union (ITU) to redefine Coordinated Universal Time (UTC) so as to replace leap seconds by leap hours. Should this proposal be adopted, the practice of inserting leap seconds would cease after a specific date. Should the Earth's rotation continue to de-accelerate at its historical rate, the next discontinuity in UTC would be an hour inserted several centuries from now. Advocates of this proposal cite the need to synchronize satellite and other systems, such as GPS, Galileo, and GLONASS, which did not exist and were not envisioned when the current system was adopted. They note that leap second insertions can be and have been incorrectly implemented or accounted for. Such errors have to date had localized impact, but they could cause serious mishaps involving loss of life. For example, some GPS receivers have been known to fail simply because there was no leap second after a long enough interval, other GPS receivers failed because the leap second information was broadcast more than three months in advance, and some commercial software used for internet time-transfer Network Time Protocol (NTP) could either discard all data received after a leap second or interpret it as a frequency change. The ambiguity associated with the extra second could also disrupt financial accounting and certain forms of encryption. Those opposed to the proposal question the need for a change, and also point out the costs of adjusting to the proposed change and its inconvenience to amateur astronomers and others who rely upon astronomical calculations published in advance. Reports have been circulated that the cost of checking and correcting software to accommodate the new definition of UTC would be many millions of dollars for some systems. In October 2005 American Astronomical Society asked the ITU for a year's time to study the issue. This commission has

  7. Explaining time's arrow

    Science.gov (United States)

    Callender, Craig Adam

    This thesis is an attempt to accurately formulate and solve one of the problems associated with the direction of time. Processes in nature appear to be 'irreversible', for instance, heat flows from hot to cold but never from cold to hot. The problem of the direction of time, roughly put, is the difficulty of squaring this irreversible behavior with the apparent fact that the fundamental laws of physics are completely reversible. In the first three chapters I critically review the foundations of statistical mechanics. After arguing that entropy is an objective property of the thermodynamic world, I contrast the 'Boltzmannian' single-system approach to statistical mechanics with the 'Gibbsian' many-system approach. Based in part on its ability to handle irreversibility, I judge the Boltzmann approach to be superior from a philosophical perspective. I argue, however, that the statistical mechanical probabilities cannot be interpreted in such a way as to allow the theory to give the sort of explanation originally desired. The next four chapters are devoted to the direction of time. Chapters four and five attempt to provide the problem with the philosophically mature geography that has so far eluded it. Chapter six discusses the problem in the context of quantum mechanics, and chapter seven criticizes the problem's standard formulation. I show that the problem is really a much more general one than has previously been appreciated; indeed, I try to show that it is a problem (if it is one) afflicting all the special sciences. Finally, the remaining three chapters investigate three separate issues. Chapter eight discusses the tensed theory of time. I claim the best argument for the tensed theory relies on various temporal asymmetries, e.g., the asymmetry of causation. I provide reasons for not being persuaded by this argument. The tensed theory, I conclude, is not incoherent, as many have claimed, instead it is simply an implausible explanation of our experience. Chapter

  8. Timing of Seasonal Sales.

    OpenAIRE

    Courty, Pascal; Hao, Li

    1999-01-01

    We present a model of timing of seasonal sales where stores choose several designs at the beginning of the season without knowing wich one, if any, will be fashionable. Fashionable designs have a chance to fetch high prices in fashion markets while non-fashionable ones must be sold in a discount market. In the beginning of the season, stores charge high prices in the hope of capturing their fashion market. As the end of the season approaches with goods still on the shelves, stores adjust down...

  9. Knowledge and time

    CERN Document Server

    2017-01-01

    This is a unique volume by a unique scientist, which combines conceptual, formal, and engineering approaches in a way that is rarely seen. Its core is the relation between ways of learning and knowing on the one hand and different modes of time on the other. Partial Boolean logic and the associated notion of complementarity are used to express this relation, and mathematical tools of fundamental physics are used to formalize it. Along the way many central philosophical problems are touched and addressed, above all the mind-body problem. Completed only shortly before the death of the author, the text has been edited and annotated by the author's close collaborator Harald Atmanspacher.

  10. Aid Supplies Over Time

    DEFF Research Database (Denmark)

    Jones, Edward Samuel

    2015-01-01

    What determines how much foreign aid donors provide? Existing answers to this question point to a complex range of influences. However, the tasks of distinguishing between long- and short-run factors, as well as differences between donors, have not been adequately addressed. Taking advantage...... of data spanning nearly 50 years, this paper uses panel cointegration techniques to consider these issues. The analysis provides clear evidence for heterogeneity both between donors and over time, bandwagon effects, and a growing influence of security considerations in aid provision. Domestic...

  11. A Dialogue on Time

    DEFF Research Database (Denmark)

    Kofod, Julie Lundbak

    2017-01-01

    here are inconclusive, as it is possible for both logics to represent the sen- tences, so this experiment does not reveal a similar distinction in physics. However this test also reveals some properties of the logics: tense logic holds a local view on time while first order logic holds a global view......, on the other hand, possible to see the correspondence while looking at the property of being fundamental. Through a presentation of Onsager's re- ciprocal relation, reversibility is shown to be fundamental. In logic, fundamentality of first order logic is argued for through the standard translation. Finally...

  12. Ideologies of Time

    DEFF Research Database (Denmark)

    Berg Johansen, Christina; De Cock, Christian

    2017-01-01

    are ideologically marked. This ideological dimension offers a common sense frame that is structured around a perceived inevitability of capitalism, a market economy as the basic organizational structure of the social and economic order, and an assumption of confident access to the future. Managers envisage...... their organization’s future and make plans for organizational action in a space where ‘business as usual’ reigns, and there is little engagement with the future as fundamentally open – as a time-yet-to-come. In using a conceptual lens inspired by the work of Fredric Jameson, we first explore the details...

  13. Time to experiment…

    Directory of Open Access Journals (Sweden)

    Gráinne Conole

    2002-12-01

    Full Text Available In the last edition of ALT-J, the editorial team decided to try an experiment by creating a more interactive and critical debate on a particular article with the journal. Readers were invited to submit comments on an article by Davis and Denning entitled: 'Almost as helpful as good theory: some conceptual possibilities for the online classroom' (Davis and Denning, 2000. Summarized below are some of the key comments raised about the paper. Many thanks to everyone who took the time to send in these comments; individual acknowledgements have not been included for reasons of confidentiality.

  14. Discounting in Time

    DEFF Research Database (Denmark)

    Fahrenberg, Uli; Larsen, Kim Guldstrand

    2009-01-01

    This paper deals with the issue of discounting in weighted timed transition systems. Discounting provides a way to model optimal-cost problems for infinite runs and has applications in optimal scheduling and other areas. We show that when postulating a certain natural additivity property...... for the discounted weights of runs, there is essentially only one possible way to introduce a discounting semantics. Our proof relies on the fact that a certain functional equation essentially only has one solution, for which we provide an elementary proof....

  15. Times of interregnum

    OpenAIRE

    Bauman, Zygmunt

    2012-01-01

    Sometime in the late 1920s or early 1930s of the last century, Antonio Gramsci recorded in one of the many notebooks he filled during his long incarceration in the Turi prison1: ‘The crisis consists precisely in the fact that the old is dying and the new cannot be born; in this interregnum a great variety of morbid symptoms appear’. The term ‘interregnum’ was originally used to denote a time-lag separating the death of one royal sovereign from the enthronement of the successor. These used to ...

  16. Aid Supplies Over Time

    DEFF Research Database (Denmark)

    Jones, Edward Samuel

    The recent financial crisis has rekindled interest in the foreign aid supply behaviour of bilateral donors. Using the latest data covering the period 1960-2009, this paper examines how such behaviour is related to domestic factors. Based on a simple empirical model, a distinction is made between ...... substantial heterogeneity between countries. There is also good evidence that donor behaviour continues to evolve over time. As such, past trends in aid supplies are unlikely to provide a good guide to those of the future....

  17. Complexity, time and music

    OpenAIRE

    JEAN PIERRE BOON

    2009-01-01

    The concept of complexity as considered in terms of its algorithmic definition proposed by G.J. Chaitin and A.N. Kolmogorov is revisited for the dynamical complexity of music. When music pieces are cast in the form of time series of pitch variations, concepts of dynamical systems theory can be used to define new quantities such as the {\\em dimensionality} as a measure of the {\\em global temporal dynamics} of a music piece, and the Shanon {\\em entropy} as an evaluation of its {\\em local dynami...

  18. The Timing of Sonoluminescence

    CERN Document Server

    Brennan, Thomas E

    2011-01-01

    We measured the timing of sonoluminescence by observing laser light scattered from a sonoluminescing bubble. We performed this measurement on 17.8 kHz, 13.28 kHz and 7920 Hz systems and found that the flash typically occurs 100 nanoseconds before the minimum radius, contrary to previous claims that the flash always occurs within a nanosecond of the minimum radius. These results imply that hot models of sonoluminescence, which require the flash to occur within a nanosecond of the minimum radius, are wrong. We propose a new model: that the flash results from the discharge of an excited cold condensate, formed during the adiabatic expansion of the bubble.

  19. Real Time Text Analysis

    Science.gov (United States)

    Senthilkumar, K.; Ruchika Mehra Vijayan, E.

    2017-11-01

    This paper aims to illustrate real time analysis of large scale data. For practical implementation we are performing sentiment analysis on live Twitter feeds for each individual tweet. To analyze sentiments we will train our data model on sentiWordNet, a polarity assigned wordNet sample by Princeton University. Our main objective will be to efficiency analyze large scale data on the fly using distributed computation. Apache Spark and Apache Hadoop eco system is used as distributed computation platform with Java as development language

  20. Time and Thermodynamics

    CERN Document Server

    Kirkland, Kyle

    2007-01-01

    Temperature is vital to the health and welfare of all living beings, and Earth's temperature varies considerably from place to place. Early humans could only live in warm areas such as the tropics. Although modern humans have the technology to keep their houses and offices warm even in cold environments, the growth and development of civilization has created unintentional effects. Cities are warmer than their surrounding regions, and on a global scale, Earth is experiencing rising temperatures. Thus, the science of thermodynamics offers an important tool to study these effects. "Time and

  1. Real time Faraday spectrometer

    Science.gov (United States)

    Smith, Jr., Tommy E.; Struve, Kenneth W.; Colella, Nicholas J.

    1991-01-01

    This invention uses a dipole magnet to bend the path of a charged particle beam. As the deflected particles exit the magnet, they are spatially dispersed in the bend-plane of the magnet according to their respective momenta and pass to a plurality of chambers having Faraday probes positioned therein. Both the current and energy distribution of the particles is then determined by the non-intersecting Faraday probes located along the chambers. The Faraday probes are magnetically isolated from each other by thin metal walls of the chambers, effectively providing real time current-versus-energy particle measurements.

  2. Reducing Uncertainty: Predictors of Stopping Chemotherapy Early and Shortened Survival Time in Platinum Resistant/Refractory Ovarian Cancer-The GCIG Symptom Benefit Study.

    Science.gov (United States)

    Roncolato, Felicia T; Joly, Florence; O'Connell, Rachel; Lanceley, Anne; Hilpert, Felix; Buizen, Luke; Okamoto, Aikou; Aotani, Eriko; Pignata, Sandro; Donnellan, Paul; Oza, Amit; Avall-Lundqvist, Elisabeth; Berek, Jonathan S; Heitz, Florian; Feeney, Amanda; Berton-Rigaud, Dominique; Stockler, Martin R; King, Madeleine; Friedlander, Michael

    2017-09-01

    Clinicians and patients often overestimate the benefits of chemotherapy, and overall survival (OS), in platinum resistant/refractory ovarian cancer (PRROC). This study sought to determine aspects of health-related quality of life and clinicopathological characteristics before starting chemotherapy that were associated with stopping chemotherapy early, shortened survival, and death within 30 days of chemotherapy. This study enrolled women with PRROC before starting palliative chemotherapy. Health-related quality of life was measured with EORTC QLQ-C30/QLQ-OV28. Chemotherapy stopped within 8 weeks of starting was defined as stopping early. Logistic regression was used to assess univariable and multivariable associations with stopping chemotherapy early and death within 30 days of chemotherapy; Cox proportional hazards regression was used to assess associations with progression-free and OS. Low baseline global health status (GHS), role function (RF), physical function (PF), and high abdominal/gastrointestinal symptom (AGIS) were associated with stopping chemotherapy early (all p Women with low GHS, RF, or PF before starting chemotherapy were more likely to stop chemotherapy early, with short OS. Self-ratings of GHS, RF, and PF could improve patient-clinician communication regarding prognosis and help decision-making in women considering chemotherapy for PRROC. Measuring aspects of health-related quality of life when considering further chemotherapy in platinum resistant/refractory ovarian cancer (PRROC) could help identify women with a particularly poor prognosis who are unlikely to benefit from chemotherapy and could therefore be spared unnecessary treatment and toxicity in their last months of life. Self-ratings of global health status, role function, and physical function could improve patient-clinician communication regarding prognosis and help decision-making in women considering chemotherapy for PRROC. © AlphaMed Press 2017.

  3. The Sun in Time

    Science.gov (United States)

    Adams, Mitzi L.; Bero, Elizabeth; Sever, Thomas L.

    1999-01-01

    Leveraging funds from NASA's Initiative to Develop Education through Astronomy and Space Science (IDEAS) program, we combined the expertise of an archaeoastronomer, a solar scientist, and a teacher to trace humankind's view of the Sun and how that has changed, from the time of Stonehenge in about 1800 B.C.E., to the time of the Maya in 700 C.E., up to the modem era. Our program was aimed at middle-school students in an attempt to explain not only how science is done today, but how science has evolved from the observations of ancient societies. From these varied cultures, we touched on methods of observing the Sun, ideas of the composition of the Sun, and the relationship of the Sun to everyday life. Further, using the von Braun Astronomical Society's Planetarium in Huntsville, Alabama as a test-bed for the program, we illustrated concepts such as solstices, equinoxes, and local noon with approximately 800 eighth grade students from the local area. Our presentation to SEPA will include a description of NASA's IDEAS program and how to go about partnering with a NASA astronomer, some slides from our planetarium program and web-site, and some hands-on activities.

  4. Is Time's Arrow Perspectival?

    CERN Document Server

    Rovelli, Carlo

    2015-01-01

    We observe entropy decrease towards the past. Does this imply that in the past the world was in a non-generic microstate? I point out an alternative. The subsystem to which we belong interacts with the universe via a relatively small number of quantities, which define a coarse graining. Entropy happens to depends on coarse-graining. Therefore the entropy we ascribe to the universe depends on the peculiar coupling between us and the rest of the universe. Low past entropy may be due to the fact that this coupling (rather than microstate of the universe) is non-generic. I argue that for any generic microstate of a sufficiently rich system there are always special subsystems defining a coarse graining for which the entropy of the rest is low in one time direction (the "past"). These are the subsystems allowing creatures that "live in time" ---such as those in the biosphere--- to exist. I reply to some objections raised to an earlier presentation of this idea, in particular by Bob Wald, David Albert and Jim Hartle...

  5. Physics Back in TIME

    Science.gov (United States)

    Korsunsky, Boris

    2014-03-01

    Recently, I came into possession of an unusual item: a collection of 1928 TIME magazines. I began flipping through the pages out of sheer curiosity—and was soon astonished by the scale and the depth of their physics coverage. Back then, TIME had a special "Science" section in almost every issue and devoted quite a bit of space to the events that would hardly be mentioned in any popular magazine these days. Some of them were fleeting and merely curious, some truly timeless. Many of the articles and notes were devoted to physics: the people, the discoveries, the inventions, the conventions. I found the reading both entertaining and enlightening and would like to offer a sampler here. I hope that these little tidbits of history will lighten up the classroom discussions and help inspire your students by reminding them that physics is a dynamic, ever-changing field to which they may well contribute one day. I have found that my own students love it when a little bit of history is brought up; it always generates interesting questions and seems to spark the students' interest in the topic.

  6. Moments in time

    Directory of Open Access Journals (Sweden)

    Marc eWittmann

    2011-10-01

    Full Text Available It has been suggested that perception and action can be understood as evolving in temporal epochs or sequential processing units. Successive events are fused into units forming a unitary experience or ‘psychological present’. Studies have identified several temporal integration levels on different time scales which are fundamental for our understanding of behaviour and subjective experience. In recent literature concerning the philosophy and neuroscience of consciousness these separate temporal processing levels are not always precisely distinguished. Therefore, empirical evidence from psychophysics and neuropsychology on these distinct temporal processing levels is presented and discussed within philosophical conceptualizations of time experience. On an elementary level, one can identify a functional moment, a basic temporal building block of perception in the range of milliseconds that defines simultaneity and succession. Below a certain threshold temporal order is not perceived, individual events are processed as co-temporal. On a second level, an experienced moment, which is based on temporal integration of up to a few seconds, has been reported in many qualitatively different experiments in perception and action. It has been suggested that this segmental processing mechanism creates temporal windows that provide a logistical basis for conscious representation and the experience of nowness. On a third level of integration, continuity of experience is enabled by working-memory in the range of multiple seconds allowing the maintenance of cognitive operations and emotional feelings, leading to mental presence, a temporal window of an individual’s experienced presence.

  7. Timing of cyber conflict.

    Science.gov (United States)

    Axelrod, Robert; Iliev, Rumen

    2014-01-28

    Nations are accumulating cyber resources in the form of stockpiles of zero-day exploits as well as other novel methods of engaging in future cyber conflict against selected targets. This paper analyzes the optimal timing for the use of such cyber resources. A simple mathematical model is offered to clarify how the timing of such a choice can depend on the stakes involved in the present situation, as well as the characteristics of the resource for exploitation. The model deals with the question of when the resource should be used given that its use today may well prevent it from being available for use later. The analysis provides concepts, theory, applications, and distinctions to promote the understanding strategy aspects of cyber conflict. Case studies include the Stuxnet attack on Iran's nuclear program, the Iranian cyber attack on the energy firm Saudi Aramco, the persistent cyber espionage carried out by the Chinese military, and an analogous case of economic coercion by China in a dispute with Japan. The effects of the rapidly expanding market for zero-day exploits are also analyzed. The goal of the paper is to promote the understanding of this domain of cyber conflict to mitigate the harm it can do, and harness the capabilities it can provide.

  8. Prime time sexual harrassment.

    Science.gov (United States)

    Grauerholz, E; King, A

    1997-04-01

    This study explores the explicit and implicit messages of sexual harassment that viewers receive when viewing prime-time television in the US. A content analysis of 48 hours of prime-time television reveals that sexual harassment on television is both highly visible and invisible. Sexual harassment is rendered visible simply by its prominence in these programs. Incidents involving quid-pro-quo harassment and environmental harassment occur with regularity on television. Furthermore, about 84% of the shows studied contained at least one incident of sexual harassment; yet these acts of sexual harassment remained largely invisible because none of the behaviors were labeled as sexual harassment. These incidents are presented in humorous ways, and victims are generally unharmed and very effective at ending the harassment. Although such programs may actually reflect the reality of many women's lives in terms of prevalence of sexual harassment, they perpetuate several myths about sexual harassment, such as that sexual harassment is not serious and that victims should be able to handle the situations themselves.

  9. Time-Delay Interferometry

    Directory of Open Access Journals (Sweden)

    Massimo Tinto

    2014-08-01

    Full Text Available Equal-arm detectors of gravitational radiation allow phase measurements many orders of magnitude below the intrinsic phase stability of the laser injecting light into their arms. This is because the noise in the laser light is common to both arms, experiencing exactly the same delay, and thus cancels when it is differenced at the photo detector. In this situation, much lower level secondary noises then set the overall performance. If, however, the two arms have different lengths (as will necessarily be the case with space-borne interferometers, the laser noise experiences different delays in the two arms and will hence not directly cancel at the detector. In order to solve this problem, a technique involving heterodyne interferometry with unequal arm lengths and independent phase-difference readouts has been proposed. It relies on properly time-shifting and linearly combining independent Doppler measurements, and for this reason it has been called time-delay interferometry (TDI. This article provides an overview of the theory, mathematical foundations, and experimental aspects associated with the implementation of TDI. Although emphasis on the application of TDI to the Laser Interferometer Space Antenna (LISA mission appears throughout this article, TDI can be incorporated into the design of any future space-based mission aiming to search for gravitational waves via interferometric measurements. We have purposely left out all theoretical aspects that data analysts will need to account for when analyzing the TDI data combinations.

  10. The little book of time

    CERN Document Server

    Mainzer, Klaus

    2002-01-01

    chapter 1 Time in the Classical and Medieval Worldviews From the Beginnings to the Pre-Socratic School Zeno's Time Arrow and Aristotle's Continuum 6 Time and Creation According to Saint Augustine 15 Time and Medieval Astronomy 18 20 Calendars and Clocks chapter 2 Time in the Worldview of Classical Physics 25 Absolute Time According to Newton 26 Relational Time According to Leibniz 30 Time in Classical Mechanics 31 Time in Kant's Epistemology 35 chapter 3 Relativistic Spacetime 43 Time in Special Relativity Theory 44 Time in General Relativity Theory 50 Time in Relativistic Cosmology 54 chapter 4 Time and the Quantum World 61 Time in Quantum Mechanics 62 Time in Quantum Field Theories 70 Time, Black Holes, and the Anthropic Principle 78 Time and Thermodynamics chapter 5 83 Time in Equilibrium Thermodynamics 84 Time in Nonequilibrium Thermodynamics 2 9 Time, Irreversibility, and Self-Organization 100 chapter 6 Time and Life 107 Time in Darwin's Theory of Evolution 108 Time in Molecular Evolution 111 Time Hierar...

  11. TIME: MEANINGS, PERSPECTIVES AND APPROACHES

    OpenAIRE

    Hanen KHANCHEL; Karim BEN KAHLA

    2012-01-01

    This paper provides a brief review of the literature related to time. First, the paper discusses ways that individuals represent time. Then the quantitative and the qualitative perspectives of time are discussed. Temporal dimensions in organizations, such as time orientation, polychronicity, and time urgency, are described. The paper may provide implications for academics whose research is related to behaviour over time

  12. Minor regression and long-time survival (56 months) in a patient with malignant pleural mesothelioma under Viscum album and Helleborus niger extracts-a case report.

    Science.gov (United States)

    Werthmann, Paul G; Saltzwedel, Gerhard; Kienle, Gunver S

    2017-12-01

    Malignant pleural mesothelioma (MPM) is a rare cancer with a dismal prognosis. Viscum album extracts (VAE) have strong immune stimulatory properties, cytotoxic effects, can downregulate cancer genes and inhibit angiogenesis. VAE are often used as an adjunct treatment in cancer patients but have rarely been investigated in MPM. Helleborus niger extracts (HNE) have been used in anticancer therapy since antiquity, and also show tumor specific cytotoxic effects. We present a case of a 64-year old woman with epithelioid MPM of the right chest with node involvement (T2N1M0, stage III). Deciding against the recommended radio-chemotherapy, surgery and pleurodesis, she opted for an integrative treatment approach and was treated with VAE and HNE. After 6 weeks' treatment, the pleural and nodal MPM manifestations were reduced by about 15%. Subsequent tumor growth was slow, and the patient remained in good health, enabling her to remain physically active until shortly before her death 56 months after the initial diagnosis. This is a rare case of an MPM patient not receiving any standard anticancer treatment; it still shows an extraordinary long survival and good performance status. We presume that VAE and HNE might had an impact on this clinically relevant outcome and therefore should be further investigated in MPM.

  13. Timing is everything :

    Energy Technology Data Exchange (ETDEWEB)

    Kobos, Peter Holmes; Walker, La Tonya Nicole; Malczynski, Leonard A.

    2013-10-01

    People save for retirement throughout their career because it is virtually impossible to save all youll need in retirement the year before you retire. Similarly, without installing incremental amounts of clean fossil, renewable or transformative energy technologies throughout the coming decades, a radical and immediate change will be near impossible the year before a policy goal is set to be in place. Therefore, our research question is, To meet our desired technical and policy goals, what are the factors that affect the rate we must install technology to achieve these goals in the coming decades? Existing models do not include full regulatory constraints due to their often complex, and inflexible approaches to solve for optimal engineering instead of robust and multidisciplinary solutions. This project outlines the theory and then develops an applied software tool to model the laboratory-to-market transition using the traditional technology readiness level (TRL) framework, but develops subsequent and a novel regulatory readiness level (RRL) and market readiness level (MRL). This tool uses the ideally-suited system dynamics framework to incorporate feedbacks and time delays. Future energy-economic-environment models, regardless of their programming platform, may adapt this software model component framework or module to further vet the likelihood of new or innovative technology moving through the laboratory, regulatory and market space. The prototype analytical framework and tool, called the Technology, Regulatory and Market Readiness Level simulation model (TRMsim) illustrates the interaction between technology research, application, policy and market dynamics as they relate to a new or innovative technology moving from the theoretical stage to full market deployment. The initial results that illustrate the models capabilities indicate for a hypothetical technology, that increasing the

  14. Technology Time Machine 2012

    DEFF Research Database (Denmark)

    Lehner, Wolfgang; Fettweis, Gerhard; Fitzek, Frank

    2013-01-01

    interaction between attendees, senior business leaders, world-renowned innovators, and the press. The goal of the Symposium is to discover key critical innovations across technologies which will alter the research and application space of the future. Topics covered the future of Wireless Technology, Smart......The IEEE Technology Time Machine (TTM) is a unique event for industry leaders, academics, and decision making government officials who direct R&D activities, plan research programs or manage portfolios of research activities. This report covers the main topics of the 2nd Symposium of future...... technologies. The Symposium brought together world renowned experts to discuss the evolutionary and revolutionary advances in technology landscapes as we look towards 2020 and beyond. TTM facilitated informal discussions among the participants and speakers thus providing an excellent opportunity for informal...

  15. High Time Resolution Astrophysics

    CERN Document Server

    Phelan, Don; Shearer, Andrew

    2008-01-01

    High Time Resolution Astrophysics (HTRA) is an important new window to the universe and a vital tool in understanding a range of phenomena from diverse objects and radiative processes. This importance is demonstrated in this volume with the description of a number of topics in astrophysics, including quantum optics, cataclysmic variables, pulsars, X-ray binaries and stellar pulsations to name a few. Underlining this science foundation, technological developments in both instrumentation and detectors are described. These instruments and detectors combined cover a wide range of timescales and can measure fluxes, spectra and polarisation. These advances make it possible for HTRA to make a big contribution to our understanding of the Universe in the next decade.

  16. Time well spent

    DEFF Research Database (Denmark)

    Fallesen, Peter

    2013-01-01

    Individuals who spent time in foster care as children fare on average worse than non-placed peers in early adult life. Recent research on the effect of foster care placement on early adult life outcomes provides mixed evidence. Some studies suggest negative effects of foster care placement on early...... adult outcomes, others find null effects. This study shows that differences in the average duration of foster care stays explain parts of these discordant findings and then test how foster care duration shapes later life outcomes using administrative data on 7 220 children. The children experienced...... different average durations of foster care because of differences in exposure to a reform. Later born cohorts spent on average 3 months longer in foster care than earlier born cohorts. Isolating exogenous variation in duration of foster care, the study finds positive effects of increased duration of foster...

  17. Intrinsic Time Quantum Gravity

    CERN Document Server

    Yu, Hoi Lai

    2016-01-01

    Correct identification of the true gauge symmetry of General Relativity being 3d spatial diffeomorphism invariant(3dDI) (not the conventional infinite tensor product group with principle fibre bundle structure), together with intrinsic time extracted from clean decomposition of the canonical structure yields a self-consistent theory of quantum gravity. A new set of fundamental commutation relations is also presented. The basic variables are the eight components of the unimodular part of the spatial dreibein and eight SU(3) generators which correspond to Klauder's momentric variables that characterize a free theory of quantum gravity. The commutation relations are not canonical, but have well defined group theoretical meanings. All fundamental entities are dimensionless; and the quantum wave functionals are preferentially in the dreibein representation. The successful quantum theory of gravity involves only broad spectrum of knowledge and deep insights but no exotic idea.

  18. Learning during stressful times.

    Science.gov (United States)

    Shors, Tracey J

    2004-01-01

    Stressful life events can have profound effects on our cognitive and motor abilities, from those that could be construed as adaptive to those not so. In this review, I discuss the general notion that acute stressful experience necessarily impairs our abilities to learn and remember. The effects of stress on operant conditioning, that is, learned helplessness, as well as those on classical conditioning procedures are discussed in the context of performance and adaptation. Studies indicating sex differences in learning during stressful times are discussed, as are those attributing different responses to the existence of multiple memory systems and nonlinear relationships. The intent of this review is to highlight the apparent plasticity of the stress response, how it might have evolved to affect both performance and learning processes, and the potential problems with interpreting stress effects on learning as either good or bad. An appreciation for its plasticity may provide new avenues for investigating its underlying neuronal mechanisms.

  19. Cell complexes through time

    Science.gov (United States)

    Klette, Reinhard

    2000-10-01

    The history of cell complexes is closely related to the birth and development of topology in general. Johann Benedict Listing (1802 - 1882) introduced the term 'topology' into mathematics in a paper published in 1847, and he also defined cell complexes for the first time in a paper published in 1862. Carl Friedrich Gauss (1777 - 1855) is often cited as the one who initiated these ideas, but he did not publish either on topology or on cell complexes. The pioneering work of Leonhard Euler (1707 - 1783) on graphs is also often cited as the birth of topology, and Euler's work was cited by Listing in 1862 as a stimulus for his research on cell complexes. There are different branches in topology which have little in common: point set topology, algebraic topology, differential topology etc. Confusion may arise if just 'topology' is specified, without clarifying the used concept. Topological subjects in mathematics are often related to continuous models, and therefore quite irrelevant to computer based solutions in image analysis. Compared to this, only a minority of topology publications in mathematics addresses discrete spaces which are appropriate for computer-based image analysis. In these cases, often the notion of a cell complex plays a crucial role. This paper briefly reports on a few of these publications. This paper is not intended to cover the very lively progress in cell complex studies within the context of image analysis during the last two decades. Basically it stops its historic review at the time when this subject in image analysis research gained speed in 1980 - 1990. As a general point of view, the paper indicates that image analysis contributes to a fusion of topological concepts, the geometric and the abstract cell structure approach and point set topology, which may lead towards new problems for the study of topologies defined on geometric or abstract cell complexes.

  20. "I felt for a long time like everything beautiful in me had been taken out": Women's suffering, remembering, and survival following the loss of child custody.

    Science.gov (United States)

    Kenny, Kathleen S; Barrington, Clare; Green, Sherri L

    2015-11-01

    Child Protective Services' (CPS) placements of children in out-of-home care disproportionately impact families marginalized by poverty, racism and criminalization. CPS' mandate to protect children from neglect and abuse is frequently criticized as failing to address the multiple social and structural domains shaping parents' lives, especially mothers. We conducted a thematic narrative analysis of in-depth interviews to explore the impact of child custody loss on 19 women who use drugs residing in Toronto, Canada. We also assessed the potential roles of intersectional forms of violence and inequities in power that can both give rise to child custody loss and mediate its consequences. Trauma was identified as a key impact of separation, further exacerbated by women's cumulative trauma histories and ongoing mother-child apartness. Women described this trauma as unbearable and reported persistent symptoms of post-traumatic stress disorder and other mental health conditions. Practices of dissociation through increased use of drugs and alcohol were central in tending to the pain of separation, and were often synergistically reinforced by heightened structural vulnerability observed in increased exposure to housing instability, intimate partner violence, and initiation of injection drug use and sex work. Women's survival hinged largely on hopefulness of reuniting with children, a goal pivotal to their sense of future and day-to-day intentions toward ameliorated life circumstances. Findings highlight needs for strategies addressing women's health and structural vulnerability following custody loss and also direct attention to altering institutional processes to support community-based alternatives to parent-child separation. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Timing organization of a real-time multicore processor

    DEFF Research Database (Denmark)

    Schoeberl, Martin; Sparsø, Jens

    2017-01-01

    Real-time systems need a time-predictable computing platform. Computation, communication, and access to shared resources needs to be time-predictable. We use time division multiplexing to statically schedule all computation and communication resources, such as access to main memory or message...... passing over a network-on-chip. We use time-driven communication over an asynchronous network-on-chip to enable time division multiplexing even in a globally asynchronous, locally synchronous multicore architecture. Using time division multiplexing at all levels of the architecture yields in a time......-predictable multicore processor where we can statically analyze the worst-case execution time of tasks....

  2. Time, Quantum and Information

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Leaf [Los Alamos, New Mexico (United States)

    2004-04-09

    Time, Quantum and Information, a paean to Professor Carl Friedrich von Weizsaecker, commemorates his 90th birthday. The range of Professor Weizsaecker's endeavours is an exhilarating example of what can be accomplished by one freely-soaring human spirit, who is at the same time a physicist, a philosopher, and a humanitarian. The editors, Lutz Castell and Otfried Ischebeck, have assembled an admirable collection of essays and articles written by Weizsaecker?s past students, collaborators, colleagues and acquaintances. Time, Quantum and Information offers the reader a panoply of unique insights into twentieth century science and history. Entangled with the stories about Weizsaecker?s influence on the lives of some of the contributors are discussions of the activities of German scientists during and following World War II, emphasizing their reluctance to work on atomic weapons following the war. By outlining Weizsaecker?s role in the early development of numerous tributaries of physical science, the book gives us a new glimpse into the origins of some of its disparate domains, such as nuclear physics, the physics of stellar nucleosynthesis, cosmic ray physics, fluid turbulence, and the formation of the solar system. We physicists have all studied Weizsaecker?s semi-empirical mass formula describing the binding energy of nuclei. We are aware too that both he and Hans Bethe independently discovered the nuclear cycles that provide stars with their enduring energy output. We have studied the Weizsaecker--Williams technique of calculating the bremsstrahlung of relativistic electrons. But how many of us know of Weizsaecker's work in fluid turbulence that he, like Werner Heisenberg under whom he had earned his doctorate, pursued while holed up in Farm Hall? And how many of us are aware of his introduction of turbulent viscosity to account for the origin of planetary orbits, involving the migration of mass inwards and angular momentum outwards? Moreover, before

  3. It's time for psychoneuroimmunology.

    Science.gov (United States)

    Kelley, K W

    2001-03-01

    It is intuitively obvious that the mind and the body are joined in ways that are not yet understood. The mission of the PsychoNeuroImmunology Research Society (PNIRS) is to delineate these relationships, to try to understand their connections at the molecular level and to use this knowledge to prevent and relieve human pain and suffering. Members of our Society have already made substantial and important contributions toward accomplishing these goals. For example, regulation of the neuroendocrine system by proinflammatory cytokines and development of the concept of sickness behavior have now become established and well-accepted tenets in psychoneuroimmunology. Although we possess some of the research tools that are needed to accomplish our goals, we need more. We must continue to apply new information that is constantly being generated in the biological sciences, such as what may be found in the recently completed mapping and sequencing of the human genome. There will always be fundamental discoveries that can and should be used to advance the field of psychoneuroimmunology and to help us accomplish our mission. Our research is needed to minimize human afflictions and to learn how patients can better participate in their own health management. That is why the time for psychoneuroimmunology is now.

  4. Improving theatre turnaround time.

    Science.gov (United States)

    Fletcher, Daniel; Edwards, David; Tolchard, Stephen; Baker, Richard; Berstock, James

    2017-01-01

    The NHS Institute for Innovation and Improvement has determined that a £7 million saving can be achieved per trust by improving theatre efficiency. The aim of this quality improvement project was to improve orthopaedic theatre turnaround without compromising the patient safety. We process mapped all the stages from application of dressing to knife to skin on the next patient in order to identify potential areas for improvement. Several suggestions arose which were tested in multiple PDSA cycles in a single theatre. These changes were either adopted, adapted or rejected on the basis of run chart data and theatre team feedback. Successful ideas which were adopted included, the operating department practitioner (ODP) seeing and completing check-in paperwork during the previous case rather than during turnaround, a 15 minute telephone warning to ensure the next patient was fully ready, a dedicated cleaning team mobilised during wound closure, sending for the next patient as theatre cleaning begins. Run charts demonstrate that as a result of these interventions the mean turnaround time almost halved from 66.5 minutes in July to 36.8 minutes over all PDSA cycles. This improvement has been sustained and rolled out into another theatre. As these improvements become more established we hope that additional cases will be booked, improving theatre output. The PDSA cycle continues as we believe that further gains may yet be made, and our improvements may be rolled out across other surgical specialities.

  5. Time-independent wormholes

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Zicao; Marolf, Donald; Mefford, Eric [Department of Physics, University of California,Santa Barbara, CA 93106 (United States)

    2016-12-06

    We study two-sided static wormholes with an exact Killing symmetry that translates both mouths of the wormhole toward the future. This differs from the familiar Kruskal wormhole whose time translation is future-directed only in one asymptotic region and is instead past-directed in the other. Our spacetimes are solutions to Einstein-Hilbert gravity sourced by scalar domain walls. Explicit examples are found in the thin wall approimation. More generally, we show that such spacetimes can arise in the presence of scalar fields with potentials that are C{sup 1} but not C{sup 2} and find examples numerically. However, solutions with an exact such Killing symmetry are forbidden when the scalar potential is smooth. Finally, we consider the mutual information of boundary regions associated with such wormholes in AdS/CFT. Although the interior of our solutions are unstable, we find that even mutual informations between opposite boundaries are already thermalized at any finite t in the sense that they agree with the t→∞ limit of results from the familiar AdS-Kruskal solution.

  6. Time to gather stones…

    Directory of Open Access Journals (Sweden)

    Elena Lyudvigovna Yakovleva

    2015-03-01

    Full Text Available Objective to search for ways of further development of modern Russia affected by sanctions. Methods dialectical method of cognition of the solitude phenomenon metaphorically transferred from personality to the image of Russia phenomenological method establishing a positive diversity solitude states futurological forecasting method by which the Russia development trends are visualized. Results the situation of the Russian society which appeared in solitude is not a reason for pessimism. This is positive time for reflection on the situation and correcting the errors there is a possibility to recover the Russian identity to form the image of Motherland and inclusive existence based on the culture of partnership and solidarity. Scientific novelty the analysis of the solitude state allows to detect its positive potential associated with correction of errors restoration of the image of Motherland and formation of identity. So that their effectiveness had a lasting effect it is necessary to pay attention to the inclusive education system which brings up a personality included into existence. Practical value the main provisions and conclusions of the article can be used in scientific educational and practical activities in the review and analysis of the state of modern Russian society under sanctions. nbsp

  7. Roe in Turbulent Time

    Directory of Open Access Journals (Sweden)

    Patrizia Gazzola

    2014-01-01

    Full Text Available The aim of the paper is to compare the utility of the net income (NI and of the comprehensive income for the evaluation of financial performance of the company and to verify whether the total comprehensive income (TCI is more value relevant than the net income especially in times of crisis (IAS 1, par. 5.The Financial Accounting Standards Board (FASB has continued to emphasize a financial measure called other comprehensive income (OCI as a valuable financial analysis tool. The FASB’s goal is to issue guidance to improve the comparability, the consistency and the transparency of financial reporting. Especially in the period of financial crises, OCI measure is also quite helpful to understand the company’s situation. The methodology in the elaboration of this article comes from the author’s previous research, which formed the main part of the overall research. The new research was based on the previous one but we have increased the number of financial statements analyzed by including companies of the free market for the year 2011. In the last part of the paper we show the results of empirical research on the income statement of the Czech companies, which adopted IAS/IFRS principles.

  8. Christian reckoning of time

    Directory of Open Access Journals (Sweden)

    Ks. Tomasz Stempa

    2014-12-01

    Full Text Available The issue of the liturgical calendar of the Orthodox Church is one of the topics currently being discussed. Using thejulian or neojulian liturgical calendar raises in faithful not only dilemmas or doubts, but also confusion, as shown by discussionson some social networking sites.The author of this text wants to bring closer reader to the problems of this issue and clarify the liturgical and calendarduality. This paper also develops such topics as the history of the christian calendar, reckoning of years, creation of calendars:julian, gregorian and neojulian, as well as problems arising from using two calendars within one local Church.This work shows that the use of one kind or another calendar is not a violation of dogma, but may lead to a breach ofa rule, established at the time of the Ecumenical Councils. You should be aware that the julian calendar was not strictlya calendar set up for the liturgical aims, but it was adapted for formulating the liturgical order.Experience of the liturgical life shows that, even though type of calendar is not a dogma, entering neojulian calendarpermanently divided some local Orthodox communities. Introduction of neojulian calendar was not necessary, and theevents at the beginning of the twentieth century is warning to refrain from taking radical action to reform liturgical life.Certainly this is a difficult issue that requires common action under the providence of Grace of the Holy Spirit.

  9. Time elements. [for time transformations for satellite equation of motion

    Science.gov (United States)

    Nacozy, P. E.

    1975-01-01

    Time elements are introduced for use with Sundman time transformations for satellite equations of motion. Two time elements are presented, one providing maximum accuracy when the exponent of the governing equation equals 1, the other when the exponent equals 2. Time elements and time transformations reduce local truncation error and Liapunov (in-track) instability, and provide analytical step size control. Numerical results show accuracy improvements of more than one order of magnitude when time elements are employed with time transformations in the numerical integration of the satellite equations, compared with using time transformations alone.

  10. Adenoviral vector-mediated gene transfer: timing of wild-type p53 gene expression in vivo and effect of tumor transduction on survival in a rat glioma brachytherapy model.

    Science.gov (United States)

    Bampoe, J; Glen, J; Hubbard, S L; Salhia, B; Shannon, P; Rutka, J; Bernstein, M

    2000-08-01

    This study sought to investigate modification of the radiation response in a rat 9L brain tumor model in vivo by the wild-type p53 gene (wtp53). Determination of the timing and dose of radiation therapy required the assessment of the duration of the effect of wtp53 expression on 9L tumors after in vivo transfection. Anesthetized male F-344 rats each were stereotactically inoculated with 4 x 10(4) 9L gliosarcoma cells through a skull screw into the cerebrum in the right frontal region. Twelve-day-old tumors were inoculated through the screw with recombinant adenoviral vectors under isoflurane anaesthesia: control rats with Ad5/RSV/GL2 (carrying the luciferase gene), and study rats with Ad5CMV-p53 (carrying the wtp53 gene). Brain tumors removed at specific times after transfection were measured, homogenized, and lysed and wtp53 expression determined by Western blot analysis. Four groups of nine rats were, subsequently, implanted with iodine-125 seeds 15 days post-tumor inoculation to give a minimum tumor dose of 40 or 60 Gy. We demonstrated transfer of wtp53 into rat 9L tumors in vivo using the Ad5CMV-p53 vector. The expression of wtp53 was demonstrated to be maximum between days 1 and 3 post-vector inoculation. Tumors expressing wtp53 were smaller than controls transfected with Ad5/RSV/GL2 but this difference was not statistically significant. Radiation made a significant difference to the survival of tumor-bearing rats. Moreover, wtp53 expression conferred a significant additional survival advantage. The expression of wtp53 significantly improves the survival of irradiated tumor-bearing rats in our model.

  11. Recursive Time-Frequency Reassignment

    OpenAIRE

    Nilsen, Geir Kjetil

    2007-01-01

    A fast algorithm for producing time-frequency representations (TFRs) is proposed. The resulting TFRs have optional time-frequency resolution up to optimality. The algorithm is further extended with a method known as time-frequency reassignment. The main implication is that time-frequency reassignment now becomes well suited for real-time implementations.

  12. SLH Timing Belt Powertrain

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Abe

    2014-04-09

    The main goal of this proposal was to develop and test a novel powertrain solution for the SLH hydroEngine, a low-cost, efficient low-head hydropower technology. Nearly two-thirds of U.S. renewable electricity is produced by hydropower (EIA 2010). According to the U.S. Department of Energy; this amount could be increased by 50% with small hydropower plants, often using already-existing dams (Hall 2004). There are more than 80,000 existing dams, and of these, less than 4% generate power (Blankinship 2009). In addition, there are over 800 irrigation districts in the U.S., many with multiple, non-power, low-head drops. These existing, non-power dams and irrigation drops could be retrofitted to produce distributed, baseload, renewable energy with appropriate technology. The problem is that most existing dams are low-head, or less than 30 feet in height (Ragon 2009). Only about 2% of the available low-head hydropower resource in the U.S. has been developed, leaving more than 70 GW of annual mean potential low-head capacity untapped (Hall 2004). Natel Energy, Inc. is developing a low-head hydropower turbine that operates efficiently at heads less than 6 meters and is cost-effective for deployment across multiple low-head structures. Because of the unique racetrack-like path taken by the prime-movers in the SLH, a flexible powertrain is required. Historically, the only viable technological solution was roller chain. Despite the having the ability to easily attach blades, roller chain is characterized by significant drawbacks, including high cost, wear, and vibration from chordal action. Advanced carbon- fiber-reinforced timing belts have been recently developed which, coupled with a novel belt attachment system developed by Natel Energy, result in a large reduction in moving parts, reduced mass and cost, and elimination of chordal action for increased fatigue life. The work done in this project affirmatively addressed each of the following 3 major uncertainties concerning

  13. Fourteen Times the Earth

    Science.gov (United States)

    2004-08-01

    ESO HARPS Instrument Discovers Smallest Ever Extra-Solar Planet Summary A European team of astronomers [1] has discovered the lightest known planet orbiting a star other than the sun (an "exoplanet"). The new exoplanet orbits the bright star mu Arae located in the southern constellation of the Altar. It is the second planet discovered around this star and completes a full revolution in 9.5 days. With a mass of only 14 times the mass of the Earth, the new planet lies at the threshold of the largest possible rocky planets, making it a possible super Earth-like object. Uranus, the smallest of the giant planets of the Solar System has a similar mass. However Uranus and the new exoplanet differ so much by their distance from the host star that their formation and structure are likely to be very different. This discovery was made possible by the unprecedented accuracy of the HARPS spectrograph on ESO's 3.6-m telescope at La Silla, which allows radial velocities to be measured with a precision better than 1 m/s. It is another clear demonstration of the European leadership in the field of exoplanet research. PR Photo 25a/04: The HARPS Spectrograph and the 3.6m Telescope PR Photo 25b/04: Observed Velocity Variation of mu Arae (3.6m/HARPS, 1.2m Swiss/CORALIE, AAT/UCLES) PR Photo 25c/04: Velocity Variation of mu Arae Observed by HARPS (3.6m/HARPS) PR Photo 25d/04: "Velocity Curve" of mu Arae A unique planet hunting machine ESO PR Photo 25a/04 ESO PR Photo 25a/04 The HARPS Spectrograph and the 3.6m Telescope [Preview - JPEG: 602 x 400 pix - 211k] [Normal - JPEG: 1202 x 800 pix - 645k] Caption: ESO PR Photo 25a/04 represents a montage of the HARPS spectrograph and the 3.6m telescope at La Silla. The upper left shows the dome of the telescope, while the upper right illustrates the telescope itself. The HARPS spectrograph is shown in the lower image during laboratory tests. The vacuum tank is open so that some of the high-precision components inside can be seen. Since the first

  14. Response Features Determining Spike Times

    Directory of Open Access Journals (Sweden)

    Barry J. Richmond

    1999-01-01

    redundant with that carried by the coarse structure. Thus, the existence of precisely timed spike patterns carrying stimulus-related information does not imply control of spike timing at precise time scales.

  15. Prothrombin time in retinitis pigmentosa

    Directory of Open Access Journals (Sweden)

    Vinchurkar Manisha

    1998-01-01

    Full Text Available The prothrombin time was recorded for 87 primary retinitis pigmentosa (RP patients belonging to three different clinical categories. All categories showed prothrombin time higher than normal. There was no correlation between the age of onset and the prothrombin time, nor between duration of disease and the prothrombin time. The high prothrombin time in patients with RP suggests that further study of prothrombin time and related factors may help in better understanding of the pathogenesis of RP.

  16. Prothrombin time in retinitis pigmentosa

    OpenAIRE

    Vinchurkar Manisha

    1998-01-01

    The prothrombin time was recorded for 87 primary retinitis pigmentosa (RP) patients belonging to three different clinical categories. All categories showed prothrombin time higher than normal. There was no correlation between the age of onset and the prothrombin time, nor between duration of disease and the prothrombin time. The high prothrombin time in patients with RP suggests that further study of prothrombin time and related factors may help in better understanding of the pathogenesis of RP.

  17. Reaction Time and Anticipation Time: Effects of Development.

    Science.gov (United States)

    Thomas, Jerry R.; And Others

    1981-01-01

    Results of a study indicated that, as age increased from seven to 20 years, reaction time decreased, with males having a more rapid reaction time than females. Beginning at age 10 or 11, subjects developed better motor plans and relied less on rapid reaction time to achieve good anticipation time. (FG)

  18. Composite continuous time random walks

    Science.gov (United States)

    Hilfer, Rudolf

    2017-12-01

    Random walks in composite continuous time are introduced. Composite time flow is the product of translational time flow and fractional time flow [see Chem. Phys. 84, 399 (2002)]. The continuum limit of composite continuous time random walks gives a diffusion equation where the infinitesimal generator of time flow is the sum of a first order and a fractional time derivative. The latter is specified as a generalized Riemann-Liouville derivative. Generalized and binomial Mittag-Leffler functions are found as the exact results for waiting time density and mean square displacement.

  19. Discovering timing feature interactions with timed UML 2 interactions

    DEFF Research Database (Denmark)

    Störrle, Harald; Knapp, Alexander

    2016-01-01

    patterns of timing specifications and show how they can be translated into UML 2 interactions with time constraints. We define a semantics that allows us to define and check coherence and consistency conditions of timing specifications. RESULTS: We provide a systematic process for mapping timing...... requirements into timed UML interactions and algorithms for checking their coherence and consistency. CONCLUSIONS: With our approach, it becomes easier to check and validate timing specifications. It is not our ambition to achieve complete coverage, i.e., discovering all timing specification defects. Instead...

  20. Tuberculosis in ancient times

    Directory of Open Access Journals (Sweden)

    Louise Cilliers

    2008-09-01

    Full Text Available In spite of an array of effective antibiotics, tuberculosis is still very common in developing countries where overcrowding, malnutrition and poor hygienic conditions prevail. Over the past 30 years associated HIV infection has worsened the situation by increasing the infection rate and mortality of tuberculosis. Of those diseases caused by a single organism only HIV causes more deaths internationally than tuberculosis. The tubercle bacillus probably first infected man in Neolithic times, and then via infected cattle, but the causative Mycobacteriacea have been in existence for 300 million years. Droplet infection is the most common way of acquiring tuberculosis, although ingestion (e.g. of infected cows’ milk may occur. Tuberculosis probably originated in Africa. The earliest path gnomonic evidence of human tuberculosis in man was found in osteo-archaeological findings of bone tuberculosis (Pott’s disease of the spine in the skeleton of anEgyptian priest from the 21st Dynasty (approximately 1 000 BC. Suggestive but not conclusiveevidence of tuberculotic lesions had been found in even earlier skeletons from Egypt and Europe. Medical hieroglyphics from ancient Egypt are silent on the disease, which could be tuberculosis,as do early Indian and Chinese writings. The Old Testament refers to the disease schachapeth, translated as phthisis in the Greek Septuagint. Although the Bible is not specific about this condition, tuberculosis is still called schachapeth in modern Hebrew. In pre-Hippocratic Greece Homer did not mention phthisis, a word meaning non-specific wasting of the body. However. Alexander of Tralles (6th century BC seemed to narrow the concept down to a specific disease, and in the Hippocratic Corpus (5th-4th centuries BC phthisis can be recognised as tuberculosis. It was predominantly a respiratory disease commonly seen and considered to be caused by an imbalance of bodily humours. It was commonest in autumn, winter and spring