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Sample records for randomly selected cohort

  1. Blocked Randomization with Randomly Selected Block Sizes

    Directory of Open Access Journals (Sweden)

    Jimmy Efird

    2010-12-01

    Full Text Available When planning a randomized clinical trial, careful consideration must be given to how participants are selected for various arms of a study. Selection and accidental bias may occur when participants are not assigned to study groups with equal probability. A simple random allocation scheme is a process by which each participant has equal likelihood of being assigned to treatment versus referent groups. However, by chance an unequal number of individuals may be assigned to each arm of the study and thus decrease the power to detect statistically significant differences between groups. Block randomization is a commonly used technique in clinical trial design to reduce bias and achieve balance in the allocation of participants to treatment arms, especially when the sample size is small. This method increases the probability that each arm will contain an equal number of individuals by sequencing participant assignments by block. Yet still, the allocation process may be predictable, for example, when the investigator is not blind and the block size is fixed. This paper provides an overview of blocked randomization and illustrates how to avoid selection bias by using random block sizes.

  2. Minimization over randomly selected lines

    Directory of Open Access Journals (Sweden)

    Ismet Sahin

    2013-07-01

    Full Text Available This paper presents a population-based evolutionary optimization method for minimizing a given cost function. The mutation operator of this method selects randomly oriented lines in the cost function domain, constructs quadratic functions interpolating the cost function at three different points over each line, and uses extrema of the quadratics as mutated points. The crossover operator modifies each mutated point based on components of two points in population, instead of one point as is usually performed in other evolutionary algorithms. The stopping criterion of this method depends on the number of almost degenerate quadratics. We demonstrate that the proposed method with these mutation and crossover operations achieves faster and more robust convergence than the well-known Differential Evolution and Particle Swarm algorithms.

  3. High Entropy Random Selection Protocols

    NARCIS (Netherlands)

    H. Buhrman (Harry); M. Christandl (Matthias); M. Koucky (Michal); Z. Lotker (Zvi); B. Patt-Shamir; M. Charikar; K. Jansen; O. Reingold; J. Rolim

    2007-01-01

    textabstractIn this paper, we construct protocols for two parties that do not trust each other, to generate random variables with high Shannon entropy. We improve known bounds for the trade off between the number of rounds, length of communication and the entropy of the outcome.

  4. Rapid, easy, and cheap randomization: prospective evaluation in a study cohort

    Directory of Open Access Journals (Sweden)

    Parker Melissa J

    2012-06-01

    Full Text Available Abstract Background When planning a randomized controlled trial (RCT, investigators must select randomization and allocation procedures based upon a variety of factors. While third party randomization is cited as being among the most desirable randomization processes, many third party randomization procedures are neither feasible nor cost-effective for small RCTs, including pilot RCTs. In this study we present our experience with a third party randomization and allocation procedure that utilizes current technology to achieve randomization in a rapid, reliable, and cost-effective manner. Methods This method was developed by the investigators for use in a small 48-participant parallel group RCT with four study arms. As a nested study, the reliability of this randomization procedure was prospectively evaluated in this cohort. The primary outcome of this nested study was the proportion of subjects for whom allocation information was obtained by the Research Assistant within 15 min of the initial participant randomization request. A secondary outcome was the average time for communicating participant group assignment back to the Research Assistant. Descriptive information regarding any failed attempts at participant randomization as well as costs attributable to use of this method were also recorded. Statistical analyses included the calculation of simple proportions and descriptive statistics. Results Forty-eight participants were successfully randomized and group allocation instruction was received for 46 (96% within 15 min of the Research Assistant placing the initial randomization request. Time elapsed in minutes until receipt of participant allocation instruction was Mean (SD 3.1 +/− 3.6; Median (IQR 2 (2,3; Range (1–20 for the entire cohort of 48. For the two participants for whom group allocation information was not received by the Research Assistant within the 15-min pass threshold, this information was obtained following a second

  5. 47 CFR 1.1603 - Conduct of random selection.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Conduct of random selection. 1.1603 Section 1.1603 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE Random Selection Procedures for Mass Media Services General Procedures § 1.1603 Conduct of random selection. The...

  6. 47 CFR 1.1602 - Designation for random selection.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Designation for random selection. 1.1602 Section 1.1602 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE Random Selection Procedures for Mass Media Services General Procedures § 1.1602 Designation for random selection...

  7. Testing, Selection, and Implementation of Random Number Generators

    National Research Council Canada - National Science Library

    Collins, Joseph C

    2008-01-01

    An exhaustive evaluation of state-of-the-art random number generators with several well-known suites of tests provides the basis for selection of suitable random number generators for use in stochastic simulations...

  8. Random effect selection in generalised linear models

    DEFF Research Database (Denmark)

    Denwood, Matt; Houe, Hans; Forkman, Björn

    We analysed abattoir recordings of meat inspection codes with possible relevance to onfarm animal welfare in cattle. Random effects logistic regression models were used to describe individual-level data obtained from 461,406 cattle slaughtered in Denmark. Our results demonstrate that the largest...

  9. Interference-aware random beam selection for spectrum sharing systems

    KAUST Repository

    Abdallah, Mohamed M.; Sayed, Mostafa M.; Alouini, Mohamed-Slim; Qaraqe, Khalid A.

    2012-01-01

    . In this paper, we develop interference-aware random beam selection schemes that provide enhanced throughput for the secondary link under the condition that the interference observed at the primary link is within a predetermined acceptable value. For a secondary

  10. Selectivity and sparseness in randomly connected balanced networks.

    Directory of Open Access Journals (Sweden)

    Cengiz Pehlevan

    Full Text Available Neurons in sensory cortex show stimulus selectivity and sparse population response, even in cases where no strong functionally specific structure in connectivity can be detected. This raises the question whether selectivity and sparseness can be generated and maintained in randomly connected networks. We consider a recurrent network of excitatory and inhibitory spiking neurons with random connectivity, driven by random projections from an input layer of stimulus selective neurons. In this architecture, the stimulus-to-stimulus and neuron-to-neuron modulation of total synaptic input is weak compared to the mean input. Surprisingly, we show that in the balanced state the network can still support high stimulus selectivity and sparse population response. In the balanced state, strong synapses amplify the variation in synaptic input and recurrent inhibition cancels the mean. Functional specificity in connectivity emerges due to the inhomogeneity caused by the generative statistical rule used to build the network. We further elucidate the mechanism behind and evaluate the effects of model parameters on population sparseness and stimulus selectivity. Network response to mixtures of stimuli is investigated. It is shown that a balanced state with unselective inhibition can be achieved with densely connected input to inhibitory population. Balanced networks exhibit the "paradoxical" effect: an increase in excitatory drive to inhibition leads to decreased inhibitory population firing rate. We compare and contrast selectivity and sparseness generated by the balanced network to randomly connected unbalanced networks. Finally, we discuss our results in light of experiments.

  11. The signature of positive selection at randomly chosen loci.

    OpenAIRE

    Przeworski, Molly

    2002-01-01

    In Drosophila and humans, there are accumulating examples of loci with a significant excess of high-frequency-derived alleles or high levels of linkage disequilibrium, relative to a neutral model of a random-mating population of constant size. These are features expected after a recent selective sweep. Their prevalence suggests that positive directional selection may be widespread in both species. However, as I show here, these features do not persist long after the sweep ends: The high-frequ...

  12. The reliability of randomly selected final year pharmacy students in ...

    African Journals Online (AJOL)

    Employing ANOVA, factorial experimental analysis, and the theory of error, reliability studies were conducted on the assessment of the drug product chloroquine phosphate tablets. The G–Study employed equal numbers of the factors for uniform control, and involved three analysts (randomly selected final year Pharmacy ...

  13. Local randomization in neighbor selection improves PRM roadmap quality

    KAUST Repository

    McMahon, Troy

    2012-10-01

    Probabilistic Roadmap Methods (PRMs) are one of the most used classes of motion planning methods. These sampling-based methods generate robot configurations (nodes) and then connect them to form a graph (roadmap) containing representative feasible pathways. A key step in PRM roadmap construction involves identifying a set of candidate neighbors for each node. Traditionally, these candidates are chosen to be the k-closest nodes based on a given distance metric. In this paper, we propose a new neighbor selection policy called LocalRand(k,K\\'), that first computes the K\\' closest nodes to a specified node and then selects k of those nodes at random. Intuitively, LocalRand attempts to benefit from random sampling while maintaining the higher levels of local planner success inherent to selecting more local neighbors. We provide a methodology for selecting the parameters k and K\\'. We perform an experimental comparison which shows that for both rigid and articulated robots, LocalRand results in roadmaps that are better connected than the traditional k-closest policy or a purely random neighbor selection policy. The cost required to achieve these results is shown to be comparable to k-closest. © 2012 IEEE.

  14. Local randomization in neighbor selection improves PRM roadmap quality

    KAUST Repository

    McMahon, Troy; Jacobs, Sam; Boyd, Bryan; Tapia, Lydia; Amato, Nancy M.

    2012-01-01

    Probabilistic Roadmap Methods (PRMs) are one of the most used classes of motion planning methods. These sampling-based methods generate robot configurations (nodes) and then connect them to form a graph (roadmap) containing representative feasible pathways. A key step in PRM roadmap construction involves identifying a set of candidate neighbors for each node. Traditionally, these candidates are chosen to be the k-closest nodes based on a given distance metric. In this paper, we propose a new neighbor selection policy called LocalRand(k,K'), that first computes the K' closest nodes to a specified node and then selects k of those nodes at random. Intuitively, LocalRand attempts to benefit from random sampling while maintaining the higher levels of local planner success inherent to selecting more local neighbors. We provide a methodology for selecting the parameters k and K'. We perform an experimental comparison which shows that for both rigid and articulated robots, LocalRand results in roadmaps that are better connected than the traditional k-closest policy or a purely random neighbor selection policy. The cost required to achieve these results is shown to be comparable to k-closest. © 2012 IEEE.

  15. Satisfaction with social networks: an examination of socioemotional selectivity theory across cohorts.

    Science.gov (United States)

    Lansford, J E; Sherman, A M; Antonucci, T C

    1998-12-01

    This study examines L. L. Carstensen's (1993, 1995) socioemotional selectivity theory within and across three cohorts spanning 4 decades. Socioemotional selectivity theory predicts that as individuals age, they narrow their social networks to devote more emotional resources to fewer relationships with close friends and family. Data from 3 cohorts of nationally representative samples were analyzed to determine whether respondents' satisfaction with the size of their social networks differed by age, cohort, or both. Results support socioemotional selectivity theory: More older adults than younger adults were satisfied with the current size of their social networks rather than wanting larger networks. These findings are consistent across all cohorts. Results are discussed with respect to social relationships across the life course.

  16. Person mobility in the design and analysis of cluster-randomized cohort prevention trials.

    Science.gov (United States)

    Vuchinich, Sam; Flay, Brian R; Aber, Lawrence; Bickman, Leonard

    2012-06-01

    Person mobility is an inescapable fact of life for most cluster-randomized (e.g., schools, hospitals, clinic, cities, state) cohort prevention trials. Mobility rates are an important substantive consideration in estimating the effects of an intervention. In cluster-randomized trials, mobility rates are often correlated with ethnicity, poverty and other variables associated with disparity. This raises the possibility that estimated intervention effects may generalize to only the least mobile segments of a population and, thus, create a threat to external validity. Such mobility can also create threats to the internal validity of conclusions from randomized trials. Researchers must decide how to deal with persons who leave study clusters during a trial (dropouts), persons and clusters that do not comply with an assigned intervention, and persons who enter clusters during a trial (late entrants), in addition to the persons who remain for the duration of a trial (stayers). Statistical techniques alone cannot solve the key issues of internal and external validity raised by the phenomenon of person mobility. This commentary presents a systematic, Campbellian-type analysis of person mobility in cluster-randomized cohort prevention trials. It describes four approaches for dealing with dropouts, late entrants and stayers with respect to data collection, analysis and generalizability. The questions at issue are: 1) From whom should data be collected at each wave of data collection? 2) Which cases should be included in the analyses of an intervention effect? and 3) To what populations can trial results be generalized? The conclusions lead to recommendations for the design and analysis of future cluster-randomized cohort prevention trials.

  17. Selection for altruism through random drift in variable size populations

    Directory of Open Access Journals (Sweden)

    Houchmandzadeh Bahram

    2012-05-01

    Full Text Available Abstract Background Altruistic behavior is defined as helping others at a cost to oneself and a lowered fitness. The lower fitness implies that altruists should be selected against, which is in contradiction with their widespread presence is nature. Present models of selection for altruism (kin or multilevel show that altruistic behaviors can have ‘hidden’ advantages if the ‘common good’ produced by altruists is restricted to some related or unrelated groups. These models are mostly deterministic, or assume a frequency dependent fitness. Results Evolutionary dynamics is a competition between deterministic selection pressure and stochastic events due to random sampling from one generation to the next. We show here that an altruistic allele extending the carrying capacity of the habitat can win by increasing the random drift of “selfish” alleles. In other terms, the fixation probability of altruistic genes can be higher than those of a selfish ones, even though altruists have a smaller fitness. Moreover when populations are geographically structured, the altruists advantage can be highly amplified and the fixation probability of selfish genes can tend toward zero. The above results are obtained both by numerical and analytical calculations. Analytical results are obtained in the limit of large populations. Conclusions The theory we present does not involve kin or multilevel selection, but is based on the existence of random drift in variable size populations. The model is a generalization of the original Fisher-Wright and Moran models where the carrying capacity depends on the number of altruists.

  18. Interference-aware random beam selection for spectrum sharing systems

    KAUST Repository

    Abdallah, Mohamed M.

    2012-09-01

    Spectrum sharing systems have been introduced to alleviate the problem of spectrum scarcity by allowing secondary unlicensed networks to share the spectrum with primary licensed networks under acceptable interference levels to the primary users. In this paper, we develop interference-aware random beam selection schemes that provide enhanced throughput for the secondary link under the condition that the interference observed at the primary link is within a predetermined acceptable value. For a secondary transmitter equipped with multiple antennas, our schemes select a random beam, among a set of power- optimized orthogonal random beams, that maximizes the capacity of the secondary link while satisfying the interference constraint at the primary receiver for different levels of feedback information describing the interference level at the primary receiver. For the proposed schemes, we develop a statistical analysis for the signal-to-noise and interference ratio (SINR) statistics as well as the capacity of the secondary link. Finally, we present numerical results that study the effect of system parameters including number of beams and the maximum transmission power on the capacity of the secondary link attained using the proposed schemes. © 2012 IEEE.

  19. Random selection of items. Selection of n1 samples among N items composing a stratum

    International Nuclear Information System (INIS)

    Jaech, J.L.; Lemaire, R.J.

    1987-02-01

    STR-224 provides generalized procedures to determine required sample sizes, for instance in the course of a Physical Inventory Verification at Bulk Handling Facilities. The present report describes procedures to generate random numbers and select groups of items to be verified in a given stratum through each of the measurement methods involved in the verification. (author). 3 refs

  20. Selective reporting bias of harm outcomes within studies: findings from a cohort of systematic reviews.

    Science.gov (United States)

    Saini, Pooja; Loke, Yoon K; Gamble, Carrol; Altman, Douglas G; Williamson, Paula R; Kirkham, Jamie J

    2014-11-21

    To determine the extent and nature of selective non-reporting of harm outcomes in clinical studies that were eligible for inclusion in a cohort of systematic reviews. Cohort study of systematic reviews from two databases. Outcome reporting bias in trials for harm outcomes (ORBIT II) in systematic reviews from the Cochrane Library and a separate cohort of systematic reviews of adverse events. 92 systematic reviews of randomised controlled trials and non-randomised studies published in the Cochrane Library between issue 9, 2012 and issue 2, 2013 (Cochrane cohort) and 230 systematic reviews published between 1 January 2007 and 31 December 2011 in other publications, synthesising data on harm outcomes (adverse event cohort). A 13 point classification system for missing outcome data on harm was developed and applied to the studies. 86% (79/92) of reviews in the Cochrane cohort did not include full data from the main harm outcome of interest of each review for all of the eligible studies included within that review; 76% (173/230) for the adverse event cohort. Overall, the single primary harm outcome was inadequately reported in 76% (705/931) of the studies included in the 92 reviews from the Cochrane cohort and not reported in 47% (4159/8837) of the 230 reviews in the adverse event cohort. In a sample of primary studies not reporting on the single primary harm outcome in the review, scrutiny of the study publication revealed that outcome reporting bias was suspected in nearly two thirds (63%, 248/393). The number of reviews suspected of outcome reporting bias as a result of missing or partially reported harm related outcomes from at least one eligible study is high. The declaration of important harms and the quality of the reporting of harm outcomes must be improved in both primary studies and systematic reviews. © Saini et al 2014.

  1. How to investigate and adjust for selection bias in cohort studies

    DEFF Research Database (Denmark)

    Nohr, Ellen A; Liew, Zeyan

    2018-01-01

    National Birth Cohort (DNBC) as examples on how to quantify selection bias and also understand the underlying selection mechanisms. Although women who chose to participate in the cohort were typically of higher social status, healthier and with less disease than all those eligible for study, differential...... of the presented methods are applicable even with limited data on non-participants and those lost to follow-up, and can also be applied to other study designs such as case-control studies and surveys. This article is protected by copyright. All rights reserved.......Longitudinal cohort studies can provide important evidence about preventable causes of disease, but the success relies heavily on the commitment of their participants, both at recruitment and during follow-up. Initial participation rates have decreased in recent decades as have willingness...

  2. The signature of positive selection at randomly chosen loci.

    Science.gov (United States)

    Przeworski, Molly

    2002-03-01

    In Drosophila and humans, there are accumulating examples of loci with a significant excess of high-frequency-derived alleles or high levels of linkage disequilibrium, relative to a neutral model of a random-mating population of constant size. These are features expected after a recent selective sweep. Their prevalence suggests that positive directional selection may be widespread in both species. However, as I show here, these features do not persist long after the sweep ends: The high-frequency alleles drift to fixation and no longer contribute to polymorphism, while linkage disequilibrium is broken down by recombination. As a result, loci chosen without independent evidence of recent selection are not expected to exhibit either of these features, even if they have been affected by numerous sweeps in their genealogical history. How then can we explain the patterns in the data? One possibility is population structure, with unequal sampling from different subpopulations. Alternatively, positive selection may not operate as is commonly modeled. In particular, the rate of fixation of advantageous mutations may have increased in the recent past.

  3. A Bayesian random effects discrete-choice model for resource selection: Population-level selection inference

    Science.gov (United States)

    Thomas, D.L.; Johnson, D.; Griffith, B.

    2006-01-01

    Modeling the probability of use of land units characterized by discrete and continuous measures, we present a Bayesian random-effects model to assess resource selection. This model provides simultaneous estimation of both individual- and population-level selection. Deviance information criterion (DIC), a Bayesian alternative to AIC that is sample-size specific, is used for model selection. Aerial radiolocation data from 76 adult female caribou (Rangifer tarandus) and calf pairs during 1 year on an Arctic coastal plain calving ground were used to illustrate models and assess population-level selection of landscape attributes, as well as individual heterogeneity of selection. Landscape attributes included elevation, NDVI (a measure of forage greenness), and land cover-type classification. Results from the first of a 2-stage model-selection procedure indicated that there is substantial heterogeneity among cow-calf pairs with respect to selection of the landscape attributes. In the second stage, selection of models with heterogeneity included indicated that at the population-level, NDVI and land cover class were significant attributes for selection of different landscapes by pairs on the calving ground. Population-level selection coefficients indicate that the pairs generally select landscapes with higher levels of NDVI, but the relationship is quadratic. The highest rate of selection occurs at values of NDVI less than the maximum observed. Results for land cover-class selections coefficients indicate that wet sedge, moist sedge, herbaceous tussock tundra, and shrub tussock tundra are selected at approximately the same rate, while alpine and sparsely vegetated landscapes are selected at a lower rate. Furthermore, the variability in selection by individual caribou for moist sedge and sparsely vegetated landscapes is large relative to the variability in selection of other land cover types. The example analysis illustrates that, while sometimes computationally intense, a

  4. Blind Measurement Selection: A Random Matrix Theory Approach

    KAUST Repository

    Elkhalil, Khalil

    2016-12-14

    This paper considers the problem of selecting a set of $k$ measurements from $n$ available sensor observations. The selected measurements should minimize a certain error function assessing the error in estimating a certain $m$ dimensional parameter vector. The exhaustive search inspecting each of the $n\\\\choose k$ possible choices would require a very high computational complexity and as such is not practical for large $n$ and $k$. Alternative methods with low complexity have recently been investigated but their main drawbacks are that 1) they require perfect knowledge of the measurement matrix and 2) they need to be applied at the pace of change of the measurement matrix. To overcome these issues, we consider the asymptotic regime in which $k$, $n$ and $m$ grow large at the same pace. Tools from random matrix theory are then used to approximate in closed-form the most important error measures that are commonly used. The asymptotic approximations are then leveraged to select properly $k$ measurements exhibiting low values for the asymptotic error measures. Two heuristic algorithms are proposed: the first one merely consists in applying the convex optimization artifice to the asymptotic error measure. The second algorithm is a low-complexity greedy algorithm that attempts to look for a sufficiently good solution for the original minimization problem. The greedy algorithm can be applied to both the exact and the asymptotic error measures and can be thus implemented in blind and channel-aware fashions. We present two potential applications where the proposed algorithms can be used, namely antenna selection for uplink transmissions in large scale multi-user systems and sensor selection for wireless sensor networks. Numerical results are also presented and sustain the efficiency of the proposed blind methods in reaching the performances of channel-aware algorithms.

  5. Social selection in cohort studies and later representation of childhood psychiatric diagnoses: The Danish National Birth Cohort

    DEFF Research Database (Denmark)

    Madsen, Kathrine Bang; Hohwü, Lena; Zhu, Jin Liang

    2017-01-01

    AIM: This study aimed to estimate the relative representation of childhood psychiatric diagnoses and use of psychotropic medication in the Danish National Birth Cohort (DNBC) compared to the general population. METHODS: The general population was identified as all childbirths in Denmark during 1998......) with corresponding 95% confidence intervals (CI) were estimated for each psychiatric diagnosis and by sex. Age at first diagnosis presented as means were compared using the one-sample t-test. RESULTS: In the DNBC, the selected childhood psychiatric diagnoses were underrepresented by 3% (PR=0.97, 95% CI 0.......94-0.99), ranging from a 20% underrepresentation for schizophrenia (PR=0.80, 95% CI 0.59-1.09) to a 6% over-representation for anxiety disorder or obsessive-compulsive disorder (PR=1.06, 95% CI 0.97-1.17). The majority of the specific diagnoses were modestly underrepresented in the DNBC compared to the general...

  6. Materials selection for oxide-based resistive random access memories

    International Nuclear Information System (INIS)

    Guo, Yuzheng; Robertson, John

    2014-01-01

    The energies of atomic processes in resistive random access memories (RRAMs) are calculated for four typical oxides, HfO 2 , TiO 2 , Ta 2 O 5 , and Al 2 O 3 , to define a materials selection process. O vacancies have the lowest defect formation energy in the O-poor limit and dominate the processes. A band diagram defines the operating Fermi energy and O chemical potential range. It is shown how the scavenger metal can be used to vary the O vacancy formation energy, via controlling the O chemical potential, and the mean Fermi energy. The high endurance of Ta 2 O 5 RRAM is related to its more stable amorphous phase and the adaptive lattice rearrangements of its O vacancy

  7. Primitive polynomials selection method for pseudo-random number generator

    Science.gov (United States)

    Anikin, I. V.; Alnajjar, Kh

    2018-01-01

    In this paper we suggested the method for primitive polynomials selection of special type. This kind of polynomials can be efficiently used as a characteristic polynomials for linear feedback shift registers in pseudo-random number generators. The proposed method consists of two basic steps: finding minimum-cost irreducible polynomials of the desired degree and applying primitivity tests to get the primitive ones. Finally two primitive polynomials, which was found by the proposed method, used in pseudorandom number generator based on fuzzy logic (FRNG) which had been suggested before by the authors. The sequences generated by new version of FRNG have low correlation magnitude, high linear complexity, less power consumption, is more balanced and have better statistical properties.

  8. Materials selection for oxide-based resistive random access memories

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Yuzheng; Robertson, John [Engineering Department, Cambridge University, Cambridge CB2 1PZ (United Kingdom)

    2014-12-01

    The energies of atomic processes in resistive random access memories (RRAMs) are calculated for four typical oxides, HfO{sub 2}, TiO{sub 2}, Ta{sub 2}O{sub 5}, and Al{sub 2}O{sub 3}, to define a materials selection process. O vacancies have the lowest defect formation energy in the O-poor limit and dominate the processes. A band diagram defines the operating Fermi energy and O chemical potential range. It is shown how the scavenger metal can be used to vary the O vacancy formation energy, via controlling the O chemical potential, and the mean Fermi energy. The high endurance of Ta{sub 2}O{sub 5} RRAM is related to its more stable amorphous phase and the adaptive lattice rearrangements of its O vacancy.

  9. Optimizing Event Selection with the Random Grid Search

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, Pushpalatha C. [Fermilab; Prosper, Harrison B. [Florida State U.; Sekmen, Sezen [Kyungpook Natl. U.; Stewart, Chip [Broad Inst., Cambridge

    2017-06-29

    The random grid search (RGS) is a simple, but efficient, stochastic algorithm to find optimal cuts that was developed in the context of the search for the top quark at Fermilab in the mid-1990s. The algorithm, and associated code, have been enhanced recently with the introduction of two new cut types, one of which has been successfully used in searches for supersymmetry at the Large Hadron Collider. The RGS optimization algorithm is described along with the recent developments, which are illustrated with two examples from particle physics. One explores the optimization of the selection of vector boson fusion events in the four-lepton decay mode of the Higgs boson and the other optimizes SUSY searches using boosted objects and the razor variables.

  10. Selective decontamination in pediatric liver transplants. A randomized prospective study.

    Science.gov (United States)

    Smith, S D; Jackson, R J; Hannakan, C J; Wadowsky, R M; Tzakis, A G; Rowe, M I

    1993-06-01

    Although it has been suggested that selective decontamination of the digestive tract (SDD) decreases postoperative aerobic Gram-negative and fungal infections in orthotopic liver transplantation (OLT), no controlled trials exist in pediatric patients. This prospective, randomized controlled study of 36 pediatric OLT patients examines the effect of short-term SDD on postoperative infection and digestive tract flora. Patients were randomized into two groups. The control group received perioperative parenteral antibiotics only. The SDD group received in addition polymyxin E, tobramycin, and amphotericin B enterally and by oropharyngeal swab postoperatively until oral intake was tolerated (6 +/- 4 days). Indications for operation, preoperative status, age, and intensive care unit and hospital length of stay were no different in SDD (n = 18) and control (n = 18) groups. A total of 14 Gram-negative infections (intraabdominal abscess 7, septicemia 5, pneumonia 1, urinary tract 1) developed in the 36 patients studied. Mortality was not significantly different in the two groups. However, there were significantly fewer patients with Gram-negative infections in the SDD group: 3/18 patients (11%) vs. 11/18 patients (50%) in the control group, P < 0.001. There was also significant reduction in aerobic Gram-negative flora in the stool and pharynx in patients receiving SDD. Gram-positive and anaerobic organisms were unaffected. We conclude that short-term postoperative SDD significantly reduces Gram-negative infections in pediatric OLT patients.

  11. Comparing conVEntional RadioTherapy with stereotactIC body radiotherapy in patients with spinAL metastases: study protocol for an randomized controlled trial following the cohort multiple randomized controlled trial design

    International Nuclear Information System (INIS)

    Velden, Joanne M. van der; Verkooijen, Helena M.; Seravalli, Enrica; Hes, Jochem; Gerlich, A. Sophie; Kasperts, Nicolien; Eppinga, Wietse S. C.; Verlaan, Jorrit-Jan; Vulpen, Marco van

    2016-01-01

    Standard radiotherapy is the treatment of first choice in patients with symptomatic spinal metastases, but is only moderately effective. Stereotactic body radiation therapy is increasingly used to treat spinal metastases, without randomized evidence of superiority over standard radiotherapy. The VERTICAL study aims to quantify the effect of stereotactic radiation therapy in patients with metastatic spinal disease. This study follows the ‘cohort multiple Randomized Controlled Trial’ design. The VERTICAL study is conducted within the PRESENT cohort. In PRESENT, all patients with bone metastases referred for radiation therapy are enrolled. For each patient, clinical and patient-reported outcomes are captured at baseline and at regular intervals during follow-up. In addition, patients give informed consent to be offered experimental interventions. Within PRESENT, 110 patients are identified as a sub cohort of eligible patients (i.e. patients with unirradiated painful, mechanically stable spinal metastases who are able to undergo stereotactic radiation therapy). After a protocol amendment, also patients with non-spinal bony metastases are eligible. From the sub cohort, a random selection of patients is offered stereotactic radiation therapy (n = 55), which patients may accept or refuse. Only patients accepting stereotactic radiation therapy sign informed consent for the VERTICAL trial. Non-selected patients (n = 55) receive standard radiotherapy, and are not aware of them serving as controls. Primary endpoint is pain response after three months. Data will be analyzed by intention to treat, complemented by instrumental variable analysis in case of substantial refusal of the stereotactic radiation therapy in the intervention arm. This study is designed to quantify the treatment response after (stereotactic) radiation therapy in patients with symptomatic spinal metastases. This is the first randomized study in palliative care following the cohort multiple Randomized

  12. Pediatric selective mutism therapy: a randomized controlled trial.

    Science.gov (United States)

    Esposito, Maria; Gimigliano, Francesca; Barillari, Maria R; Precenzano, Francesco; Ruberto, Maria; Sepe, Joseph; Barillari, Umberto; Gimigliano, Raffaele; Militerni, Roberto; Messina, Giovanni; Carotenuto, Marco

    2017-10-01

    Selective mutism (SM) is a rare disease in children coded by DSM-5 as an anxiety disorder. Despite the disabling nature of the disease, there is still no specific treatment. The aims of this study were to verify the efficacy of six-month standard psychomotor treatment and the positive changes in lifestyle, in a population of children affected by SM. Randomized controlled trial registered in the European Clinical Trials Registry (EuDract 2015-001161-36). University third level Centre (Child and Adolescent Neuropsychiatry Clinic). Study population was composed by 67 children in group A (psychomotricity treatment) (35 M, mean age 7.84±1.15) and 71 children in group B (behavioral and educational counseling) (37 M, mean age 7.75±1.36). Psychomotor treatment was administered by trained child therapists in residential settings three times per week. Each child was treated for the whole period by the same therapist and all the therapists shared the same protocol. The standard psychomotor session length is of 45 minutes. At T0 and after 6 months (T1) of treatments, patients underwent a behavioral and SM severity assessment. To verify the effects of the psychomotor management, the Child Behavior Checklist questionnaire (CBCL) and Selective Mutism Questionnaire (SMQ) were administered to the parents. After 6 months of psychomotor treatment SM children showed a significant reduction among CBCL scores such as in social relations, anxious/depressed, social problems and total problems (Pselective mutism, even if further studies are needed. The present study identifies in psychomotricity a safe and efficacy therapy for pediatric selective mutism.

  13. Combining epidemiologic and biostatistical tools to enhance variable selection in HIV cohort analyses.

    Directory of Open Access Journals (Sweden)

    Christopher Rentsch

    Full Text Available BACKGROUND: Variable selection is an important step in building a multivariate regression model for which several methods and statistical packages are available. A comprehensive approach for variable selection in complex multivariate regression analyses within HIV cohorts is explored by utilizing both epidemiological and biostatistical procedures. METHODS: Three different methods for variable selection were illustrated in a study comparing survival time between subjects in the Department of Defense's National History Study and the Atlanta Veterans Affairs Medical Center's HIV Atlanta VA Cohort Study. The first two methods were stepwise selection procedures, based either on significance tests (Score test, or on information theory (Akaike Information Criterion, while the third method employed a Bayesian argument (Bayesian Model Averaging. RESULTS: All three methods resulted in a similar parsimonious survival model. Three of the covariates previously used in the multivariate model were not included in the final model suggested by the three approaches. When comparing the parsimonious model to the previously published model, there was evidence of less variance in the main survival estimates. CONCLUSIONS: The variable selection approaches considered in this study allowed building a model based on significance tests, on an information criterion, and on averaging models using their posterior probabilities. A parsimonious model that balanced these three approaches was found to provide a better fit than the previously reported model.

  14. Blind Measurement Selection: A Random Matrix Theory Approach

    KAUST Repository

    Elkhalil, Khalil; Kammoun, Abla; Al-Naffouri, Tareq Y.; Alouini, Mohamed-Slim

    2016-01-01

    -aware fashions. We present two potential applications where the proposed algorithms can be used, namely antenna selection for uplink transmissions in large scale multi-user systems and sensor selection for wireless sensor networks. Numerical results are also

  15. Fibroid interventions: reducing symptoms today and tomorrow: extending generalizability by using a comprehensive cohort design with a randomized controlled trial.

    Science.gov (United States)

    AbdElmagied, Ahmed M; Vaughan, Lisa E; Weaver, Amy L; Laughlin-Tommaso, Shannon K; Hesley, Gina K; Woodrum, David A; Jacoby, Vanessa L; Kohi, Maureen P; Price, Thomas M; Nieves, Angel; Miller, Michael J; Borah, Bijan J; Gorny, Krzysztof R; Leppert, Phyllis C; Lemens, Maureen A; Stewart, Elizabeth A

    2016-09-01

    Uterine fibroids are an important source of morbidity for reproductive-aged women. Despite an increasing number of alternatives, hysterectomies account for about 75% of all fibroid interventional treatments. Evidence is lacking to help women and their health care providers decide among alternatives to hysterectomy. Fibroid Interventions: Reducing Symptoms Today and Tomorrow (NCT00995878, clinicaltrials.gov) is a randomized controlled trial to compare the safety, efficacy, and economics of 2 minimally invasive alternatives to hysterectomy: uterine artery embolization and magnetic resonance imaging-guided focused ultrasound surgery. Although randomized trials provide the highest level of evidence, they have been difficult to conduct in the United States for interventional fibroid treatments. Thus, contemporaneously recruiting women declining randomization may have value as an alternative strategy for comparative effectiveness research. We sought to compare baseline characteristics of randomized participants with nonrandomized participants meeting the same enrollment criteria and to determine whether combining the 2 cohorts in a comprehensive cohort design would be useful for analysis. Premenopausal women with symptomatic uterine fibroids seeking interventional therapy at 3 US academic medical centers were randomized (1:1) in 2 strata based on calculated uterine volume (<700 and ≥700 cc(3)) to undergo embolization or focused ultrasound surgery. Women who met the same inclusion criteria but declined randomization were offered enrollment in a parallel cohort. Both cohorts were followed up for a maximum of 36 months after treatment. The measures addressed in this report were baseline demographics, symptoms, fibroid and uterine characteristics, and scores on validated quality-of-life measures. Of 723 women screened, 57 were randomized and 49 underwent treatment (27 with focused ultrasound and 22 with embolization). Seven of the 8 women randomized but not treated were

  16. Strategyproof Peer Selection using Randomization, Partitioning, and Apportionment

    OpenAIRE

    Aziz, Haris; Lev, Omer; Mattei, Nicholas; Rosenschein, Jeffrey S.; Walsh, Toby

    2016-01-01

    Peer review, evaluation, and selection is a fundamental aspect of modern science. Funding bodies the world over employ experts to review and select the best proposals of those submitted for funding. The problem of peer selection, however, is much more general: a professional society may want to give a subset of its members awards based on the opinions of all members; an instructor for a MOOC or online course may want to crowdsource grading; or a marketing company may select ideas from group b...

  17. Variable Selection in Time Series Forecasting Using Random Forests

    Directory of Open Access Journals (Sweden)

    Hristos Tyralis

    2017-10-01

    Full Text Available Time series forecasting using machine learning algorithms has gained popularity recently. Random forest is a machine learning algorithm implemented in time series forecasting; however, most of its forecasting properties have remained unexplored. Here we focus on assessing the performance of random forests in one-step forecasting using two large datasets of short time series with the aim to suggest an optimal set of predictor variables. Furthermore, we compare its performance to benchmarking methods. The first dataset is composed by 16,000 simulated time series from a variety of Autoregressive Fractionally Integrated Moving Average (ARFIMA models. The second dataset consists of 135 mean annual temperature time series. The highest predictive performance of RF is observed when using a low number of recent lagged predictor variables. This outcome could be useful in relevant future applications, with the prospect to achieve higher predictive accuracy.

  18. Random-walk simulation of selected aspects of dissipative collisions

    International Nuclear Information System (INIS)

    Toeke, J.; Gobbi, A.; Matulewicz, T.

    1984-11-01

    Internuclear thermal equilibrium effects and shell structure effects in dissipative collisions are studied numerically within the framework of the model of stochastic exchanges by applying the random-walk technique. Effective blocking of the drift through the mass flux induced by the temperature difference, while leaving the variances of the mass distributions unaltered is found possible, provided an internuclear potential barrier is present. Presence of the shell structure is found to lead to characteristic correlations between the consecutive exchanges. Experimental evidence for the predicted effects is discussed. (orig.)

  19. Application of random effects to the study of resource selection by animals.

    Science.gov (United States)

    Gillies, Cameron S; Hebblewhite, Mark; Nielsen, Scott E; Krawchuk, Meg A; Aldridge, Cameron L; Frair, Jacqueline L; Saher, D Joanne; Stevens, Cameron E; Jerde, Christopher L

    2006-07-01

    1. Resource selection estimated by logistic regression is used increasingly in studies to identify critical resources for animal populations and to predict species occurrence. 2. Most frequently, individual animals are monitored and pooled to estimate population-level effects without regard to group or individual-level variation. Pooling assumes that both observations and their errors are independent, and resource selection is constant given individual variation in resource availability. 3. Although researchers have identified ways to minimize autocorrelation, variation between individuals caused by differences in selection or available resources, including functional responses in resource selection, have not been well addressed. 4. Here we review random-effects models and their application to resource selection modelling to overcome these common limitations. We present a simple case study of an analysis of resource selection by grizzly bears in the foothills of the Canadian Rocky Mountains with and without random effects. 5. Both categorical and continuous variables in the grizzly bear model differed in interpretation, both in statistical significance and coefficient sign, depending on how a random effect was included. We used a simulation approach to clarify the application of random effects under three common situations for telemetry studies: (a) discrepancies in sample sizes among individuals; (b) differences among individuals in selection where availability is constant; and (c) differences in availability with and without a functional response in resource selection. 6. We found that random intercepts accounted for unbalanced sample designs, and models with random intercepts and coefficients improved model fit given the variation in selection among individuals and functional responses in selection. Our empirical example and simulations demonstrate how including random effects in resource selection models can aid interpretation and address difficult assumptions

  20. Maternal use of selective serotonin reuptake inhibitors during pregnancy is associated with Hirschsprung's disease in newborns - a nationwide cohort study

    DEFF Research Database (Denmark)

    Nielsen, Sebastian Werngreen; Møller Ljungdalh, Pernille; Nielsen, Jan

    2017-01-01

    of the association between maternal use of selective serotonin reuptake inhibitors (SSRIs) during pregnancy and development of Hirschsprung's Disease in the newborn child. The study examined a nationwide, unselected cohort of children born in Denmark from 1 January 1996 until 12 March 2016 (n = 1,256,317). We...... of Hirschsprung's disease was 16/19.807 (0.08%) compared to 584/1.236.510 (0.05%) in the unexposed cohort. In women who redeemed a minimum of one prescription of selective serotonin reuptake inhibitors, the adjusted odds ratio for development of Hirschsprung's disease was 1.76 (95%CI: 1.07-2.92). In women who...

  1. Interference-aware random beam selection schemes for spectrum sharing systems

    KAUST Repository

    Abdallah, Mohamed; Qaraqe, Khalid; Alouini, Mohamed-Slim

    2012-01-01

    users. In this work, we develop interference-aware random beam selection schemes that provide enhanced performance for the secondary network under the condition that the interference observed by the receivers of the primary network is below a

  2. Assessing the accuracy and stability of variable selection methods for random forest modeling in ecology

    Science.gov (United States)

    Random forest (RF) modeling has emerged as an important statistical learning method in ecology due to its exceptional predictive performance. However, for large and complex ecological datasets there is limited guidance on variable selection methods for RF modeling. Typically, e...

  3. The mathematics of random mutation and natural selection for multiple simultaneous selection pressures and the evolution of antimicrobial drug resistance.

    Science.gov (United States)

    Kleinman, Alan

    2016-12-20

    The random mutation and natural selection phenomenon act in a mathematically predictable behavior, which when understood leads to approaches to reduce and prevent the failure of the use of these selection pressures when treating infections and cancers. The underlying principle to impair the random mutation and natural selection phenomenon is to use combination therapy, which forces the population to evolve to multiple selection pressures simultaneously that invoke the multiplication rule of probabilities simultaneously as well. Recently, it has been seen that combination therapy for the treatment of malaria has failed to prevent the emergence of drug-resistant variants. Using this empirical example and the principles of probability theory, the derivation of the equations describing this treatment failure is carried out. These equations give guidance as to how to use combination therapy for the treatment of cancers and infectious diseases and prevent the emergence of drug resistance. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  4. Acceptance sampling using judgmental and randomly selected samples

    Energy Technology Data Exchange (ETDEWEB)

    Sego, Landon H.; Shulman, Stanley A.; Anderson, Kevin K.; Wilson, John E.; Pulsipher, Brent A.; Sieber, W. Karl

    2010-09-01

    We present a Bayesian model for acceptance sampling where the population consists of two groups, each with different levels of risk of containing unacceptable items. Expert opinion, or judgment, may be required to distinguish between the high and low-risk groups. Hence, high-risk items are likely to be identifed (and sampled) using expert judgment, while the remaining low-risk items are sampled randomly. We focus on the situation where all observed samples must be acceptable. Consequently, the objective of the statistical inference is to quantify the probability that a large percentage of the unsampled items in the population are also acceptable. We demonstrate that traditional (frequentist) acceptance sampling and simpler Bayesian formulations of the problem are essentially special cases of the proposed model. We explore the properties of the model in detail, and discuss the conditions necessary to ensure that required samples sizes are non-decreasing function of the population size. The method is applicable to a variety of acceptance sampling problems, and, in particular, to environmental sampling where the objective is to demonstrate the safety of reoccupying a remediated facility that has been contaminated with a lethal agent.

  5. 40 CFR 761.308 - Sample selection by random number generation on any two-dimensional square grid.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Sample selection by random number... § 761.79(b)(3) § 761.308 Sample selection by random number generation on any two-dimensional square... area created in accordance with paragraph (a) of this section, select two random numbers: one each for...

  6. Exploring Mechanisms of Effective Teacher Coaching: A Tale of Two Cohorts From a Randomized Experiment

    Science.gov (United States)

    Blazar, David; Kraft, Matthew A.

    2015-01-01

    Although previous research has shown that teacher coaching can improve teaching practices and student achievement, little is known about specific features of effective coaching programs. We estimate the impact of MATCH Teacher Coaching (MTC) on a range of teacher practices using a blocked randomized trial and explore how changes in the coaching…

  7. Random Forest ensembles for detection and prediction of Alzheimer's disease with a good between-cohort robustness

    Directory of Open Access Journals (Sweden)

    A.V. Lebedev

    2014-01-01

    In the ADNI set, the best AD/HC sensitivity/specificity (88.6%/92.0% — test set was achieved by combining cortical thickness and volumetric measures. The Random Forest model resulted in significantly higher accuracy compared to the reference classifier (linear Support Vector Machine. The models trained using parcelled and high-dimensional (HD input demonstrated equivalent performance, but the former was more effective in terms of computation/memory and time costs. The sensitivity/specificity for detecting MCI-to-AD conversion (but not AD/HC classification performance was further improved from 79.5%/75%–83.3%/81.3% by a combination of morphometric measurements with ApoE-genotype and demographics (age, sex, education. When applied to the independent AddNeuroMed cohort, the best ADNI models produced equivalent performance without substantial accuracy drop, suggesting good robustness sufficient for future clinical implementation.

  8. Non-random mating for selection with restricted rates of inbreeding and overlapping generations

    NARCIS (Netherlands)

    Sonesson, A.K.; Meuwissen, T.H.E.

    2002-01-01

    Minimum coancestry mating with a maximum of one offspring per mating pair (MC1) is compared with random mating schemes for populations with overlapping generations. Optimum contribution selection is used, whereby $\\\\\\\\Delta F$ is restricted. For schemes with $\\\\\\\\Delta F$ restricted to 0.25% per

  9. Applications of random forest feature selection for fine-scale genetic population assignment.

    Science.gov (United States)

    Sylvester, Emma V A; Bentzen, Paul; Bradbury, Ian R; Clément, Marie; Pearce, Jon; Horne, John; Beiko, Robert G

    2018-02-01

    Genetic population assignment used to inform wildlife management and conservation efforts requires panels of highly informative genetic markers and sensitive assignment tests. We explored the utility of machine-learning algorithms (random forest, regularized random forest and guided regularized random forest) compared with F ST ranking for selection of single nucleotide polymorphisms (SNP) for fine-scale population assignment. We applied these methods to an unpublished SNP data set for Atlantic salmon ( Salmo salar ) and a published SNP data set for Alaskan Chinook salmon ( Oncorhynchus tshawytscha ). In each species, we identified the minimum panel size required to obtain a self-assignment accuracy of at least 90% using each method to create panels of 50-700 markers Panels of SNPs identified using random forest-based methods performed up to 7.8 and 11.2 percentage points better than F ST -selected panels of similar size for the Atlantic salmon and Chinook salmon data, respectively. Self-assignment accuracy ≥90% was obtained with panels of 670 and 384 SNPs for each data set, respectively, a level of accuracy never reached for these species using F ST -selected panels. Our results demonstrate a role for machine-learning approaches in marker selection across large genomic data sets to improve assignment for management and conservation of exploited populations.

  10. 40 CFR 761.306 - Sampling 1 meter square surfaces by random selection of halves.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Sampling 1 meter square surfaces by...(b)(3) § 761.306 Sampling 1 meter square surfaces by random selection of halves. (a) Divide each 1 meter square portion where it is necessary to collect a surface wipe test sample into two equal (or as...

  11. Intake of Total and Subgroups of Fat Minimally Affect the Associations between Selected Single Nucleotide Polymorphisms in the PPARγ Pathway and Changes in Anthropometry among European Adults from Cohorts of the DiOGenes Study

    DEFF Research Database (Denmark)

    Larsen, Sofus C; Ängquist, Lars; Østergaard, Jane N

    2016-01-01

    nucleotide polymorphisms (SNPs) within 4 genes in the PPARγ pathway are associated with the OR of being a BW gainer or with annual changes in anthropometry and whether intake of total fat, monounsaturated fat, polyunsaturated fat, or saturated fat has a modifying effect on these associations. METHODS: A case......-noncase study included 11,048 men and women from cohorts in the European Diet, Obesity and Genes study; 5552 were cases, defined as individuals with the greatest BW gain during follow-up, and 6548 were randomly selected, including 5496 noncases. We selected 4 genes [CCAAT/enhancer binding protein β (CEBPB...

  12. Hebbian Learning in a Random Network Captures Selectivity Properties of the Prefrontal Cortex

    Science.gov (United States)

    Lindsay, Grace W.

    2017-01-01

    Complex cognitive behaviors, such as context-switching and rule-following, are thought to be supported by the prefrontal cortex (PFC). Neural activity in the PFC must thus be specialized to specific tasks while retaining flexibility. Nonlinear “mixed” selectivity is an important neurophysiological trait for enabling complex and context-dependent behaviors. Here we investigate (1) the extent to which the PFC exhibits computationally relevant properties, such as mixed selectivity, and (2) how such properties could arise via circuit mechanisms. We show that PFC cells recorded from male and female rhesus macaques during a complex task show a moderate level of specialization and structure that is not replicated by a model wherein cells receive random feedforward inputs. While random connectivity can be effective at generating mixed selectivity, the data show significantly more mixed selectivity than predicted by a model with otherwise matched parameters. A simple Hebbian learning rule applied to the random connectivity, however, increases mixed selectivity and enables the model to match the data more accurately. To explain how learning achieves this, we provide analysis along with a clear geometric interpretation of the impact of learning on selectivity. After learning, the model also matches the data on measures of noise, response density, clustering, and the distribution of selectivities. Of two styles of Hebbian learning tested, the simpler and more biologically plausible option better matches the data. These modeling results provide clues about how neural properties important for cognition can arise in a circuit and make clear experimental predictions regarding how various measures of selectivity would evolve during animal training. SIGNIFICANCE STATEMENT The prefrontal cortex is a brain region believed to support the ability of animals to engage in complex behavior. How neurons in this area respond to stimuli—and in particular, to combinations of stimuli (

  13. Performance Evaluation of User Selection Protocols in Random Networks with Energy Harvesting and Hardware Impairments

    Directory of Open Access Journals (Sweden)

    Tan Nhat Nguyen

    2016-01-01

    Full Text Available In this paper, we evaluate performances of various user selection protocols under impact of hardware impairments. In the considered protocols, a Base Station (BS selects one of available Users (US to serve, while the remaining USs harvest the energy from the Radio Frequency (RF transmitted by the BS. We assume that all of the US randomly appear around the BS. In the Random Selection Protocol (RAN, the BS randomly selects a US to transmit the data. In the second proposed protocol, named Minimum Distance Protocol (MIND, the US that is nearest to the BS will be chosen. In the Optimal Selection Protocol (OPT, the US providing the highest channel gain between itself and the BS will be served. For performance evaluation, we derive exact and asymptotic closed-form expressions of average Outage Probability (OP over Rayleigh fading channels. We also consider average harvested energy per a US. Finally, Monte-Carlo simulations are then performed to verify the theoretical results.

  14. Simulated Performance Evaluation of a Selective Tracker Through Random Scenario Generation

    DEFF Research Database (Denmark)

    Hussain, Dil Muhammad Akbar

    2006-01-01

    performance assessment. Therefore, a random target motion scenario is adopted. Its implementation in particular for testing the proposed selective track splitting algorithm using Kalman filters is investigated through a number of performance parameters which gives the activity profile of the tracking scenario......  The paper presents a simulation study on the performance of a target tracker using selective track splitting filter algorithm through a random scenario implemented on a digital signal processor.  In a typical track splitting filter all the observation which fall inside a likelihood ellipse...... are used for update, however, in our proposed selective track splitting filter less number of observations are used for track update.  Much of the previous performance work [1] has been done on specific (deterministic) scenarios. One of the reasons for considering the specific scenarios, which were...

  15. TEHRAN AIR POLLUTANTS PREDICTION BASED ON RANDOM FOREST FEATURE SELECTION METHOD

    Directory of Open Access Journals (Sweden)

    A. Shamsoddini

    2017-09-01

    Full Text Available Air pollution as one of the most serious forms of environmental pollutions poses huge threat to human life. Air pollution leads to environmental instability, and has harmful and undesirable effects on the environment. Modern prediction methods of the pollutant concentration are able to improve decision making and provide appropriate solutions. This study examines the performance of the Random Forest feature selection in combination with multiple-linear regression and Multilayer Perceptron Artificial Neural Networks methods, in order to achieve an efficient model to estimate carbon monoxide and nitrogen dioxide, sulfur dioxide and PM2.5 contents in the air. The results indicated that Artificial Neural Networks fed by the attributes selected by Random Forest feature selection method performed more accurate than other models for the modeling of all pollutants. The estimation accuracy of sulfur dioxide emissions was lower than the other air contaminants whereas the nitrogen dioxide was predicted more accurate than the other pollutants.

  16. Tehran Air Pollutants Prediction Based on Random Forest Feature Selection Method

    Science.gov (United States)

    Shamsoddini, A.; Aboodi, M. R.; Karami, J.

    2017-09-01

    Air pollution as one of the most serious forms of environmental pollutions poses huge threat to human life. Air pollution leads to environmental instability, and has harmful and undesirable effects on the environment. Modern prediction methods of the pollutant concentration are able to improve decision making and provide appropriate solutions. This study examines the performance of the Random Forest feature selection in combination with multiple-linear regression and Multilayer Perceptron Artificial Neural Networks methods, in order to achieve an efficient model to estimate carbon monoxide and nitrogen dioxide, sulfur dioxide and PM2.5 contents in the air. The results indicated that Artificial Neural Networks fed by the attributes selected by Random Forest feature selection method performed more accurate than other models for the modeling of all pollutants. The estimation accuracy of sulfur dioxide emissions was lower than the other air contaminants whereas the nitrogen dioxide was predicted more accurate than the other pollutants.

  17. Relationship of Work Hours with Selected Health Behaviors and Academic Progress among a College Student Cohort

    Science.gov (United States)

    Miller, Kim; Danner, Fred; Staten, Ruth

    2008-01-01

    Approximately 57% of college students work while attending school. Health risks related to working while in college have not been widely studied. Objective: The authors' purpose in this study was to determine associations between hours worked, binge drinking, sleep habits, and academic performance among a college student cohort. Participants and…

  18. Continuous-Time Mean-Variance Portfolio Selection with Random Horizon

    International Nuclear Information System (INIS)

    Yu, Zhiyong

    2013-01-01

    This paper examines the continuous-time mean-variance optimal portfolio selection problem with random market parameters and random time horizon. Treating this problem as a linearly constrained stochastic linear-quadratic optimal control problem, I explicitly derive the efficient portfolios and efficient frontier in closed forms based on the solutions of two backward stochastic differential equations. Some related issues such as a minimum variance portfolio and a mutual fund theorem are also addressed. All the results are markedly different from those in the problem with deterministic exit time. A key part of my analysis involves proving the global solvability of a stochastic Riccati equation, which is interesting in its own right

  19. Continuous-Time Mean-Variance Portfolio Selection with Random Horizon

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Zhiyong, E-mail: yuzhiyong@sdu.edu.cn [Shandong University, School of Mathematics (China)

    2013-12-15

    This paper examines the continuous-time mean-variance optimal portfolio selection problem with random market parameters and random time horizon. Treating this problem as a linearly constrained stochastic linear-quadratic optimal control problem, I explicitly derive the efficient portfolios and efficient frontier in closed forms based on the solutions of two backward stochastic differential equations. Some related issues such as a minimum variance portfolio and a mutual fund theorem are also addressed. All the results are markedly different from those in the problem with deterministic exit time. A key part of my analysis involves proving the global solvability of a stochastic Riccati equation, which is interesting in its own right.

  20. Randomized placebo control study of metformin in psoriasis patients with metabolic syndrome (systemic treatment cohort

    Directory of Open Access Journals (Sweden)

    Surjit Singh

    2017-01-01

    Full Text Available Background: Psoriasis has been found to be associated with obesity, metabolic syndrome (MS, diabetes, and cardiovascular risk factors. Metformin treatment showed improvement in cardiovascular risk factors and hyperinsulinemia. Objective: To evaluate the efficacy and safety of metformin in psoriasis patients with MS. Materials and Methods: This was a single-center, parallel-group, randomized, open-label study with blinded end point assessment of metformin (1000 mg once daily for 12 weeks; n = 20 and placebo (n = 18 in psoriasis patients with MS. Total sample size was 38 participants. Results: Statistically significant improvement was observed in mean percentage change in erythema, scaling, and induration (ESI (P = 0.048 in metformin as compared to placebo while mean percentage change in psoriasis area and severity index (PASI and physician global assessment (PGA scores was not significant (PASI - P = 0.215, PGA - P = 0.070. There was a statistically significant difference in percentage of parameters of MS improved following 12 weeks of treatment in metformin (19% as compared to placebo (8.9% group (P = 0.046. Statistically significant difference in percentage of patients achieving 75% reduction in ESI scores (P = 0.024. Significant improvement was observed in mean weight, body mass index (BMI, total cholesterol, and low-density lipoprotein (LDL cholesterol in metformin group as compared to placebo. Improvement in BMI, fasting plasma glucose, serum triglycerides, high-density lipoprotein, LDL, systolic blood pressure, diastolic blood pressure, and total cholesterol was statistically significant in metformin group over the period of 12 weeks. There was no significant difference in adverse events in two groups except weight gain. Conclusion: Metformin has shown improvement in psoriasis and parameters of MS, hence can be used for the benefit of psoriasis patients having MS. Large, controlled studies are needed to confirm.

  1. Emergence of multilevel selection in the prisoner's dilemma game on coevolving random networks

    International Nuclear Information System (INIS)

    Szolnoki, Attila; Perc, Matjaz

    2009-01-01

    We study the evolution of cooperation in the prisoner's dilemma game, whereby a coevolutionary rule is introduced that molds the random topology of the interaction network in two ways. First, existing links are deleted whenever a player adopts a new strategy or its degree exceeds a threshold value; second, new links are added randomly after a given number of game iterations. These coevolutionary processes correspond to the generic formation of new links and deletion of existing links that, especially in human societies, appear frequently as a consequence of ongoing socialization, change of lifestyle or death. Due to the counteraction of deletions and additions of links the initial heterogeneity of the interaction network is qualitatively preserved, and thus cannot be held responsible for the observed promotion of cooperation. Indeed, the coevolutionary rule evokes the spontaneous emergence of a powerful multilevel selection mechanism, which despite the sustained random topology of the evolving network, maintains cooperation across the whole span of defection temptation values.

  2. Impact of sending email reminders of the legal requirement for posting results on ClinicalTrials.gov: cohort embedded pragmatic randomized controlled trial.

    Science.gov (United States)

    Maruani, Annabel; Boutron, Isabelle; Baron, Gabriel; Ravaud, Philippe

    2014-09-19

    To evaluate the impact of sending an email to responsible parties of completed trials that do not comply with the Food and Drug Administration Amendments Act 801 legislation, to remind them of the legal requirement to post results. Cohort embedded pragmatic randomized controlled trial. Trials registered on ClinicalTrials.gov. 190 out of 379 trials randomly selected by computer generated randomization list to receive the intervention (personalized emails structured as a survey and sent by one of us to responsible parties of the trials, indirectly reminding them of the legal requirement and potential penalties for non-compliance). The primary outcome was the proportion of results posted on ClinicalTrials.gov at three months. The secondary outcome was the proportion posted at six months. In a second step, two assessors blinded to the intervention group collected the date of the first results being received on ClinicalTrials.gov. A post hoc sensitivity analysis excluding trials wrongly included was performed. Among 379 trials included, 190 were randomized to receive the email intervention. The rate of posting of results did not differ at three months between trials with or without the intervention: 36/190 (19%) v 24/189 (13%), respectively (relative risk 1.5, 95% confidence interval 0.9 to 2.4, P=0.096) but did at six months: 46/190 (24%) v 27/189 (14%), 1.7, 1.1 to 2.6, P=0.014. In the sensitivity analysis, which excluded 48/379 trials (13%), 26/190 (14%) and 22/189 (12%), respectively, results were significant at three months (relative risk 5.1, 1.1 to 22.9, P=0.02) and at six months (4.1, 1.3 to 10.6, P=0.001). Sending email reminders about the FDA's legal requirement to post results at ClinicalTrials.gov improved significantly the posting rate at six months but not at three months.Trial registration ClinicalTrials.gov NCT01658254. © Maruani et al 2014.

  3. Topology-selective jamming of fully-connected, code-division random-access networks

    Science.gov (United States)

    Polydoros, Andreas; Cheng, Unjeng

    1990-01-01

    The purpose is to introduce certain models of topology selective stochastic jamming and examine its impact on a class of fully-connected, spread-spectrum, slotted ALOHA-type random access networks. The theory covers dedicated as well as half-duplex units. The dominant role of the spatial duty factor is established, and connections with the dual concept of time selective jamming are discussed. The optimal choices of coding rate and link access parameters (from the users' side) and the jamming spatial fraction are numerically established for DS and FH spreading.

  4. Random drift versus selection in academic vocabulary: an evolutionary analysis of published keywords.

    Directory of Open Access Journals (Sweden)

    R Alexander Bentley

    Full Text Available The evolution of vocabulary in academic publishing is characterized via keyword frequencies recorded in the ISI Web of Science citations database. In four distinct case-studies, evolutionary analysis of keyword frequency change through time is compared to a model of random copying used as the null hypothesis, such that selection may be identified against it. The case studies from the physical sciences indicate greater selection in keyword choice than in the social sciences. Similar evolutionary analyses can be applied to a wide range of phenomena; wherever the popularity of multiple items through time has been recorded, as with web searches, or sales of popular music and books, for example.

  5. Random drift versus selection in academic vocabulary: an evolutionary analysis of published keywords.

    Science.gov (United States)

    Bentley, R Alexander

    2008-08-27

    The evolution of vocabulary in academic publishing is characterized via keyword frequencies recorded in the ISI Web of Science citations database. In four distinct case-studies, evolutionary analysis of keyword frequency change through time is compared to a model of random copying used as the null hypothesis, such that selection may be identified against it. The case studies from the physical sciences indicate greater selection in keyword choice than in the social sciences. Similar evolutionary analyses can be applied to a wide range of phenomena; wherever the popularity of multiple items through time has been recorded, as with web searches, or sales of popular music and books, for example.

  6. Comparative Evaluations of Randomly Selected Four Point-of-Care Glucometer Devices in Addis Ababa, Ethiopia.

    Science.gov (United States)

    Wolde, Mistire; Tarekegn, Getahun; Kebede, Tedla

    2018-05-01

    Point-of-care glucometer (PoCG) devices play a significant role in self-monitoring of the blood sugar level, particularly in the follow-up of high blood sugar therapeutic response. The aim of this study was to evaluate blood glucose test results performed with four randomly selected glucometers on diabetes and control subjects versus standard wet chemistry (hexokinase) methods in Addis Ababa, Ethiopia. A prospective cross-sectional study was conducted on randomly selected 200 study participants (100 participants with diabetes and 100 healthy controls). Four randomly selected PoCG devices (CareSens N, DIAVUE Prudential, On Call Extra, i-QARE DS-W) were evaluated against hexokinase method and ISO 15197:2003 and ISO 15197:2013 standards. The minimum and maximum blood sugar values were recorded by CareSens N (21 mg/dl) and hexokinase method (498.8 mg/dl), respectively. The mean sugar values of all PoCG devices except On Call Extra showed significant differences compared with the reference hexokinase method. Meanwhile, all four PoCG devices had strong positive relationship (>80%) with the reference method (hexokinase). On the other hand, none of the four PoCG devices fulfilled the minimum accuracy measurement set by ISO 15197:2003 and ISO 15197:2013 standards. In addition, the linear regression analysis revealed that all four selected PoCG overestimated the glucose concentrations. The overall evaluation of the selected four PoCG measurements were poorly correlated with standard reference method. Therefore, before introducing PoCG devices to the market, there should be a standardized evaluation platform for validation. Further similar large-scale studies on other PoCG devices also need to be undertaken.

  7. Selective Screening Strategies for Gestational Diabetes: A Prospective Cohort Observational Study

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    Sumaiya Adam

    2017-01-01

    Full Text Available Aim. We aimed to develop a prediction model for the diagnosis of gestational diabetes and to evaluate the performance of published prediction tools on our population. Methods. We conducted a cohort study on nondiabetic women  10%, 25.6% of cases were detected without the HbA1c, and 25.8% of cases would have been detected with the HbA1c. The 9 published scoring systems performed poorly. Conclusion. We propose a nomogram-based score that can be used at first antenatal visit to identify women at high risk of GDM.

  8. Selection bias and subject refusal in a cluster-randomized controlled trial

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    Rochelle Yang

    2017-07-01

    Full Text Available Abstract Background Selection bias and non-participation bias are major methodological concerns which impact external validity. Cluster-randomized controlled trials are especially prone to selection bias as it is impractical to blind clusters to their allocation into intervention or control. This study assessed the impact of selection bias in a large cluster-randomized controlled trial. Methods The Improved Cardiovascular Risk Reduction to Enhance Rural Primary Care (ICARE study examined the impact of a remote pharmacist-led intervention in twelve medical offices. To assess eligibility, a standardized form containing patient demographics and medical information was completed for each screened patient. Eligible patients were approached by the study coordinator for recruitment. Both the study coordinator and the patient were aware of the site’s allocation prior to consent. Patients who consented or declined to participate were compared across control and intervention arms for differing characteristics. Statistical significance was determined using a two-tailed, equal variance t-test and a chi-square test with adjusted Bonferroni p-values. Results were adjusted for random cluster variation. Results There were 2749 completed screening forms returned to research staff with 461 subjects who had either consented or declined participation. Patients with poorly controlled diabetes were found to be significantly more likely to decline participation in intervention sites compared to those in control sites. A higher mean diastolic blood pressure was seen in patients with uncontrolled hypertension who declined in the control sites compared to those who declined in the intervention sites. However, these findings were no longer significant after adjustment for random variation among the sites. After this adjustment, females were now found to be significantly more likely to consent than males (odds ratio = 1.41; 95% confidence interval = 1.03, 1

  9. Methodology Series Module 1: Cohort Studies.

    Science.gov (United States)

    Setia, Maninder Singh

    2016-01-01

    Cohort design is a type of nonexperimental or observational study design. In a cohort study, the participants do not have the outcome of interest to begin with. They are selected based on the exposure status of the individual. They are then followed over time to evaluate for the occurrence of the outcome of interest. Some examples of cohort studies are (1) Framingham Cohort study, (2) Swiss HIV Cohort study, and (3) The Danish Cohort study of psoriasis and depression. These studies may be prospective, retrospective, or a combination of both of these types. Since at the time of entry into the cohort study, the individuals do not have outcome, the temporality between exposure and outcome is well defined in a cohort design. If the exposure is rare, then a cohort design is an efficient method to study the relation between exposure and outcomes. A retrospective cohort study can be completed fast and is relatively inexpensive compared with a prospective cohort study. Follow-up of the study participants is very important in a cohort study, and losses are an important source of bias in these types of studies. These studies are used to estimate the cumulative incidence and incidence rate. One of the main strengths of a cohort study is the longitudinal nature of the data. Some of the variables in the data will be time-varying and some may be time independent. Thus, advanced modeling techniques (such as fixed and random effects models) are useful in analysis of these studies.

  10. Methodology series module 1: Cohort studies

    Directory of Open Access Journals (Sweden)

    Maninder Singh Setia

    2016-01-01

    Full Text Available Cohort design is a type of nonexperimental or observational study design. In a cohort study, the participants do not have the outcome of interest to begin with. They are selected based on the exposure status of the individual. They are then followed over time to evaluate for the occurrence of the outcome of interest. Some examples of cohort studies are (1 Framingham Cohort study, (2 Swiss HIV Cohort study, and (3 The Danish Cohort study of psoriasis and depression. These studies may be prospective, retrospective, or a combination of both of these types. Since at the time of entry into the cohort study, the individuals do not have outcome, the temporality between exposure and outcome is well defined in a cohort design. If the exposure is rare, then a cohort design is an efficient method to study the relation between exposure and outcomes. A retrospective cohort study can be completed fast and is relatively inexpensive compared with a prospective cohort study. Follow-up of the study participants is very important in a cohort study, and losses are an important source of bias in these types of studies. These studies are used to estimate the cumulative incidence and incidence rate. One of the main strengths of a cohort study is the longitudinal nature of the data. Some of the variables in the data will be time-varying and some may be time independent. Thus, advanced modeling techniques (such as fixed and random effects models are useful in analysis of these studies.

  11. Fuzzy Random λ-Mean SAD Portfolio Selection Problem: An Ant Colony Optimization Approach

    Science.gov (United States)

    Thakur, Gour Sundar Mitra; Bhattacharyya, Rupak; Mitra, Swapan Kumar

    2010-10-01

    To reach the investment goal, one has to select a combination of securities among different portfolios containing large number of securities. Only the past records of each security do not guarantee the future return. As there are many uncertain factors which directly or indirectly influence the stock market and there are also some newer stock markets which do not have enough historical data, experts' expectation and experience must be combined with the past records to generate an effective portfolio selection model. In this paper the return of security is assumed to be Fuzzy Random Variable Set (FRVS), where returns are set of random numbers which are in turn fuzzy numbers. A new λ-Mean Semi Absolute Deviation (λ-MSAD) portfolio selection model is developed. The subjective opinions of the investors to the rate of returns of each security are taken into consideration by introducing a pessimistic-optimistic parameter vector λ. λ-Mean Semi Absolute Deviation (λ-MSAD) model is preferred as it follows absolute deviation of the rate of returns of a portfolio instead of the variance as the measure of the risk. As this model can be reduced to Linear Programming Problem (LPP) it can be solved much faster than quadratic programming problems. Ant Colony Optimization (ACO) is used for solving the portfolio selection problem. ACO is a paradigm for designing meta-heuristic algorithms for combinatorial optimization problem. Data from BSE is used for illustration.

  12. From Protocols to Publications: A Study in Selective Reporting of Outcomes in Randomized Trials in Oncology

    Science.gov (United States)

    Raghav, Kanwal Pratap Singh; Mahajan, Sminil; Yao, James C.; Hobbs, Brian P.; Berry, Donald A.; Pentz, Rebecca D.; Tam, Alda; Hong, Waun K.; Ellis, Lee M.; Abbruzzese, James; Overman, Michael J.

    2015-01-01

    Purpose The decision by journals to append protocols to published reports of randomized trials was a landmark event in clinical trial reporting. However, limited information is available on how this initiative effected transparency and selective reporting of clinical trial data. Methods We analyzed 74 oncology-based randomized trials published in Journal of Clinical Oncology, the New England Journal of Medicine, and The Lancet in 2012. To ascertain integrity of reporting, we compared published reports with their respective appended protocols with regard to primary end points, nonprimary end points, unplanned end points, and unplanned analyses. Results A total of 86 primary end points were reported in 74 randomized trials; nine trials had greater than one primary end point. Nine trials (12.2%) had some discrepancy between their planned and published primary end points. A total of 579 nonprimary end points (median, seven per trial) were planned, of which 373 (64.4%; median, five per trial) were reported. A significant positive correlation was found between the number of planned and nonreported nonprimary end points (Spearman r = 0.66; P < .001). Twenty-eight studies (37.8%) reported a total of 65 unplanned end points; 52 (80.0%) of which were not identified as unplanned. Thirty-one (41.9%) and 19 (25.7%) of 74 trials reported a total of 52 unplanned analyses involving primary end points and 33 unplanned analyses involving nonprimary end points, respectively. Studies reported positive unplanned end points and unplanned analyses more frequently than negative outcomes in abstracts (unplanned end points odds ratio, 6.8; P = .002; unplanned analyses odd ratio, 8.4; P = .007). Conclusion Despite public and reviewer access to protocols, selective outcome reporting persists and is a major concern in the reporting of randomized clinical trials. To foster credible evidence-based medicine, additional initiatives are needed to minimize selective reporting. PMID:26304898

  13. Causal relationship between obesity and vitamin D status: bi-directional Mendelian randomization analysis of multiple cohorts.

    Directory of Open Access Journals (Sweden)

    Karani S Vimaleswaran

    Full Text Available Obesity is associated with vitamin D deficiency, and both are areas of active public health concern. We explored the causality and direction of the relationship between body mass index (BMI and 25-hydroxyvitamin D [25(OHD] using genetic markers as instrumental variables (IVs in bi-directional Mendelian randomization (MR analysis.We used information from 21 adult cohorts (up to 42,024 participants with 12 BMI-related SNPs (combined in an allelic score to produce an instrument for BMI and four SNPs associated with 25(OHD (combined in two allelic scores, separately for genes encoding its synthesis or metabolism as an instrument for vitamin D. Regression estimates for the IVs (allele scores were generated within-study and pooled by meta-analysis to generate summary effects. Associations between vitamin D scores and BMI were confirmed in the Genetic Investigation of Anthropometric Traits (GIANT consortium (n = 123,864. Each 1 kg/m(2 higher BMI was associated with 1.15% lower 25(OHD (p = 6.52×10⁻²⁷. The BMI allele score was associated both with BMI (p = 6.30×10⁻⁶² and 25(OHD (-0.06% [95% CI -0.10 to -0.02], p = 0.004 in the cohorts that underwent meta-analysis. The two vitamin D allele scores were strongly associated with 25(OHD (p≤8.07×10⁻⁵⁷ for both scores but not with BMI (synthesis score, p = 0.88; metabolism score, p = 0.08 in the meta-analysis. A 10% higher genetically instrumented BMI was associated with 4.2% lower 25(OHD concentrations (IV ratio: -4.2 [95% CI -7.1 to -1.3], p = 0.005. No association was seen for genetically instrumented 25(OHD with BMI, a finding that was confirmed using data from the GIANT consortium (p≥0.57 for both vitamin D scores.On the basis of a bi-directional genetic approach that limits confounding, our study suggests that a higher BMI leads to lower 25(OHD, while any effects of lower 25(OHD increasing BMI are likely to be small. Population level interventions to

  14. Turning point or selection? The effect of rustication on subsequent health for the Chinese Cultural Revolution cohort.

    Science.gov (United States)

    Fan, Wen

    2016-05-01

    During the Chinese Cultural Revolution (1966-76), Chairman Mao sent 17 million urban youth to rural areas to be "reeducated." These "sent-down" youth spent years working alongside peasants, enduring inadequate diets, shelter and medical attention. What were the consequences for subsequent health? Was there a benefit to individuals in the leading or trailing edges of this cohort? Was this a fundamental turning point or were selection process at work? Drawing on the 1994 State and Life Chances in Urban China Survey, I find the health disadvantage at midlife is mostly borne by members of the trailing-edge sub-cohort who lived in the countryside for more than five years. Results from propensity-score analysis indicate a selection process: those who suffered most came from disadvantaged backgrounds. Life chances following the rusticates' return home, however, either do not differ from those who stayed in cities or do not relate to health, refuting the turning-point view, at least in terms of midlife health. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Optimization of the Dutch Matrix Test by Random Selection of Sentences From a Preselected Subset

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    Rolph Houben

    2015-04-01

    Full Text Available Matrix tests are available for speech recognition testing in many languages. For an accurate measurement, a steep psychometric function of the speech materials is required. For existing tests, it would be beneficial if it were possible to further optimize the available materials by increasing the function’s steepness. The objective is to show if the steepness of the psychometric function of an existing matrix test can be increased by selecting a homogeneous subset of recordings with the steepest sentence-based psychometric functions. We took data from a previous multicenter evaluation of the Dutch matrix test (45 normal-hearing listeners. Based on half of the data set, first the sentences (140 out of 311 with a similar speech reception threshold and with the steepest psychometric function (≥9.7%/dB were selected. Subsequently, the steepness of the psychometric function for this selection was calculated from the remaining (unused second half of the data set. The calculation showed that the slope increased from 10.2%/dB to 13.7%/dB. The resulting subset did not allow the construction of enough balanced test lists. Therefore, the measurement procedure was changed to randomly select the sentences during testing. Random selection may interfere with a representative occurrence of phonemes. However, in our material, the median phonemic occurrence remained close to that of the original test. This finding indicates that phonemic occurrence is not a critical factor. The work highlights the possibility that existing speech tests might be improved by selecting sentences with a steep psychometric function.

  16. Using Random Forests to Select Optimal Input Variables for Short-Term Wind Speed Forecasting Models

    Directory of Open Access Journals (Sweden)

    Hui Wang

    2017-10-01

    Full Text Available Achieving relatively high-accuracy short-term wind speed forecasting estimates is a precondition for the construction and grid-connected operation of wind power forecasting systems for wind farms. Currently, most research is focused on the structure of forecasting models and does not consider the selection of input variables, which can have significant impacts on forecasting performance. This paper presents an input variable selection method for wind speed forecasting models. The candidate input variables for various leading periods are selected and random forests (RF is employed to evaluate the importance of all variable as features. The feature subset with the best evaluation performance is selected as the optimal feature set. Then, kernel-based extreme learning machine is constructed to evaluate the performance of input variables selection based on RF. The results of the case study show that by removing the uncorrelated and redundant features, RF effectively extracts the most strongly correlated set of features from the candidate input variables. By finding the optimal feature combination to represent the original information, RF simplifies the structure of the wind speed forecasting model, shortens the training time required, and substantially improves the model’s accuracy and generalization ability, demonstrating that the input variables selected by RF are effective.

  17. From Protocols to Publications: A Study in Selective Reporting of Outcomes in Randomized Trials in Oncology.

    Science.gov (United States)

    Raghav, Kanwal Pratap Singh; Mahajan, Sminil; Yao, James C; Hobbs, Brian P; Berry, Donald A; Pentz, Rebecca D; Tam, Alda; Hong, Waun K; Ellis, Lee M; Abbruzzese, James; Overman, Michael J

    2015-11-01

    The decision by journals to append protocols to published reports of randomized trials was a landmark event in clinical trial reporting. However, limited information is available on how this initiative effected transparency and selective reporting of clinical trial data. We analyzed 74 oncology-based randomized trials published in Journal of Clinical Oncology, the New England Journal of Medicine, and The Lancet in 2012. To ascertain integrity of reporting, we compared published reports with their respective appended protocols with regard to primary end points, nonprimary end points, unplanned end points, and unplanned analyses. A total of 86 primary end points were reported in 74 randomized trials; nine trials had greater than one primary end point. Nine trials (12.2%) had some discrepancy between their planned and published primary end points. A total of 579 nonprimary end points (median, seven per trial) were planned, of which 373 (64.4%; median, five per trial) were reported. A significant positive correlation was found between the number of planned and nonreported nonprimary end points (Spearman r = 0.66; P medicine, additional initiatives are needed to minimize selective reporting. © 2015 by American Society of Clinical Oncology.

  18. Transarterial Therapy for Hepatocellular Carcinoma: Which Technique Is More Effective? A Systematic Review of Cohort and Randomized Studies

    International Nuclear Information System (INIS)

    Marelli, Laura; Stigliano, Rosa; Triantos, Christos; Senzolo, Marco; Cholongitas, Evangelos; Davies, Neil; Tibballs, Jonathan; Meyer, Tim; Patch, David W.; Burroughs, Andrew K.

    2007-01-01

    Background. Chemoembolization (TACE) improves survival in cirrhotic patients with hepatocellular carcinoma (HCC). The optimal schedule, or whether embolization (TAE) alone gives the same survival advantage, is not known. Purpose. To evaluate whether specific patient characteristics and/or radiological transarterial techniques result in better outcomes. Method. A PubMed search was carried out for cohort and randomized trials (n = 175) testing transarterial therapies; meta-analysis was performed where appropriate. Results. Anticancer drugs were used as sole agent in 75% of cases (double 15% and triple 6%): doxorubicin (36%), cisplatin (31%), epirubicin (12%), mitoxantrone (8%), mitomycin (8%), and SMANCS (5%). Embolizing agents used were: gelatin sponge particles (71%), polyvinyl alcohol (PVA) particles (8%), degradable starch microspheres (DSM) (4%), and embospheres (4%). Sessions per patient were 2.5 ± 1.5 (interval: 2 months). Objective response was 40 ± 20%; survival rates at 1, 2, 3, and 5 years were: 62 ± 20%, 42 ± 17%, 30 ± 15%, and 19 ± 16%, respectively, and survival time was 18 ± 9.5 months. The post-TACE complications were: acute liver failure, 7.5% (range 0-49%); acute renal failure, 1.8% (0-13%); encephalopathy, 1.8% (0-16%); ascites, 8.3% (0-52%); upper gastrointestinal bleeding; 3% (0-22%); and hepatic or splenic abscess, 1.3% (0-2.5%). Treatment-related mortality was 2.4% (0-9.5%), mainly due to acute liver failure. Our meta-analysis of nine randomized controlled trials (RCTs) confirmed that TACE improves survival; but a meta-analysis of TACE versus TAE alone (3 RCTs, 412 patients) demonstrated no survival difference. Conclusions. No chemotherapeutic agent appears better than any other. There is no evidence for benefit with lipiodol. Gelatin sponge is the most used embolic agent, but PVA particles may be better. TAE appears as effective as TACE. New strategies to reduce the risk of post-TACE complications are required

  19. On theoretical models of gene expression evolution with random genetic drift and natural selection.

    Directory of Open Access Journals (Sweden)

    Osamu Ogasawara

    2009-11-01

    Full Text Available The relative contributions of natural selection and random genetic drift are a major source of debate in the study of gene expression evolution, which is hypothesized to serve as a bridge from molecular to phenotypic evolution. It has been suggested that the conflict between views is caused by the lack of a definite model of the neutral hypothesis, which can describe the long-run behavior of evolutionary change in mRNA abundance. Therefore previous studies have used inadequate analogies with the neutral prediction of other phenomena, such as amino acid or nucleotide sequence evolution, as the null hypothesis of their statistical inference.In this study, we introduced two novel theoretical models, one based on neutral drift and the other assuming natural selection, by focusing on a common property of the distribution of mRNA abundance among a variety of eukaryotic cells, which reflects the result of long-term evolution. Our results demonstrated that (1 our models can reproduce two independently found phenomena simultaneously: the time development of gene expression divergence and Zipf's law of the transcriptome; (2 cytological constraints can be explicitly formulated to describe long-term evolution; (3 the model assuming that natural selection optimized relative mRNA abundance was more consistent with previously published observations than the model of optimized absolute mRNA abundances.The models introduced in this study give a formulation of evolutionary change in the mRNA abundance of each gene as a stochastic process, on the basis of previously published observations. This model provides a foundation for interpreting observed data in studies of gene expression evolution, including identifying an adequate time scale for discriminating the effect of natural selection from that of random genetic drift of selectively neutral variations.

  20. A Signal Detection Approach in a Multiple Cohort Study: Different Admission Tools Uniquely Select Different Successful Students

    Directory of Open Access Journals (Sweden)

    Linda van Ooijen-van der Linden

    2018-05-01

    Full Text Available Using multiple admission tools in university admission procedures is common practice. This is particularly useful if different admission tools uniquely select different subgroups of students who will be successful in university programs. A signal-detection approach was used to investigate the accuracy of Secondary School grade point average (SSGPA, an admission test score (ACS, and a non-cognitive score (NCS in uniquely selecting successful students. This was done for three consecutive first year cohorts of a broad psychology program. Each applicant's score on SSGPA, ACS, or NCS alone—and on seven combinations of these scores, all considered separate “admission tools”—was compared at two different (medium and high cut-off scores (criterion levels. Each of the tools selected successful students who were not selected by any of the other tools. Both sensitivity and specificity were enhanced by implementing multiple tools. The signal-detection approach distinctively provided useful information for decisions on admission instruments and cut-off scores.

  1. Assessing the accuracy and stability of variable selection methods for random forest modeling in ecology.

    Science.gov (United States)

    Fox, Eric W; Hill, Ryan A; Leibowitz, Scott G; Olsen, Anthony R; Thornbrugh, Darren J; Weber, Marc H

    2017-07-01

    Random forest (RF) modeling has emerged as an important statistical learning method in ecology due to its exceptional predictive performance. However, for large and complex ecological data sets, there is limited guidance on variable selection methods for RF modeling. Typically, either a preselected set of predictor variables are used or stepwise procedures are employed which iteratively remove variables according to their importance measures. This paper investigates the application of variable selection methods to RF models for predicting probable biological stream condition. Our motivating data set consists of the good/poor condition of n = 1365 stream survey sites from the 2008/2009 National Rivers and Stream Assessment, and a large set (p = 212) of landscape features from the StreamCat data set as potential predictors. We compare two types of RF models: a full variable set model with all 212 predictors and a reduced variable set model selected using a backward elimination approach. We assess model accuracy using RF's internal out-of-bag estimate, and a cross-validation procedure with validation folds external to the variable selection process. We also assess the stability of the spatial predictions generated by the RF models to changes in the number of predictors and argue that model selection needs to consider both accuracy and stability. The results suggest that RF modeling is robust to the inclusion of many variables of moderate to low importance. We found no substantial improvement in cross-validated accuracy as a result of variable reduction. Moreover, the backward elimination procedure tended to select too few variables and exhibited numerous issues such as upwardly biased out-of-bag accuracy estimates and instabilities in the spatial predictions. We use simulations to further support and generalize results from the analysis of real data. A main purpose of this work is to elucidate issues of model selection bias and instability to ecologists interested in

  2. Analysis and applications of a frequency selective surface via a random distribution method

    International Nuclear Information System (INIS)

    Xie Shao-Yi; Huang Jing-Jian; Yuan Nai-Chang; Liu Li-Guo

    2014-01-01

    A novel frequency selective surface (FSS) for reducing radar cross section (RCS) is proposed in this paper. This FSS is based on the random distribution method, so it can be called random surface. In this paper, the stacked patches serving as periodic elements are employed for RCS reduction. Previous work has demonstrated the efficiency by utilizing the microstrip patches, especially for the reflectarray. First, the relevant theory of the method is described. Then a sample of a three-layer variable-sized stacked patch random surface with a dimension of 260 mm×260 mm is simulated, fabricated, and measured in order to demonstrate the validity of the proposed design. For the normal incidence, the 8-dB RCS reduction can be achieved both by the simulation and the measurement in 8 GHz–13 GHz. The oblique incidence of 30° is also investigated, in which the 7-dB RCS reduction can be obtained in a frequency range of 8 GHz–14 GHz. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  3. Out-of-pocket costs, primary care frequent attendance and sample selection: Estimates from a longitudinal cohort design.

    Science.gov (United States)

    Pymont, Carly; McNamee, Paul; Butterworth, Peter

    2018-03-20

    This paper examines the effect of out-of-pocket costs on subsequent frequent attendance in primary care using data from the Personality and Total Health (PATH) Through Life Project, a representative community cohort study from Canberra, Australia. The analysis sample comprised 1197 respondents with two or more GP consultations, and uses survey data linked to administrative health service use (Medicare) data which provides data on the number of consultations and out-of-pocket costs. Respondents identified in the highest decile of GP use in a year were defined as Frequent Attenders (FAs). Logistic regression models that did not account for potential selection effects showed that out-of-pocket costs incurred during respondents' prior two consultations were significantly associated with subsequent FA status. Respondents who incurred higher costs ($15-$35; or >$35) were less likely to become FAs than those who incurred no or low (attenders. Copyright © 2018. Published by Elsevier B.V.

  4. Children born by women with rheumatoid arthritis have increased susceptibility for selected chronic diseases – a nationwide cohort study

    DEFF Research Database (Denmark)

    Jølving, Line Riis; Nielsen, Jan; Kesmodel, Ulrik Schiøler

    2018-01-01

    OBJECTIVE: Fetal exposure to maternal rheumatoid arthritis (RA) might impact the long-term risk of disease in the offspring. We examined a possible association between maternal RA and 15 selected groups of chronic diseases in the offspring. METHODS: This nationwide cohort study was based...... used, taking a large range of confounders into consideration, computing the Hazard Ratios (HR) of child- and adolescence diseases. RESULTS: In children being exposed to maternal RA in utero, the HR's of thyroid diseases was 2.19 (95% CI, 1.14 - 4.21), epilepsy 1.61 (95% CI, 1.16 - 2.25), and RA 2.......89 (95% CI, 2.06 - 4.05). The HR's for anxiety and personality disorders and chronic lung disease including asthma were in the range of 1.15 - 1.16, but these were not statistically significant. CONCLUSIONS: Our results suggest that in utero exposure to maternal RA is associated with an increased risk...

  5. Selective oropharyngeal decontamination versus selective digestive decontamination in critically ill patients: a meta-analysis of randomized controlled trials

    Directory of Open Access Journals (Sweden)

    Zhao D

    2015-07-01

    Full Text Available Di Zhao,1,* Jian Song,2,* Xuan Gao,3 Fei Gao,4 Yupeng Wu,2 Yingying Lu,5 Kai Hou1 1Department of Neurosurgery, The First Hospital of Hebei Medical University, 2Department of Neurosurgery, 3Department of Neurology, The Second Hospital of Hebei Medical University, 4Hebei Provincial Procurement Centers for Medical Drugs and Devices, 5Department of Neurosurgery, The Second Hospital of Hebei Medical University, Shijiazhuang People’s Republic of China *These authors contributed equally to this work Background: Selective digestive decontamination (SDD and selective oropharyngeal decontamination (SOD are associated with reduced mortality and infection rates among patients in intensive care units (ICUs; however, whether SOD has a superior effect than SDD remains uncertain. Hence, we conducted a meta-analysis of randomized controlled trials (RCTs to compare SOD with SDD in terms of clinical outcomes and antimicrobial resistance rates in patients who were critically ill. Methods: RCTs published in PubMed, Embase, and Web of Science were systematically reviewed to compare the effects of SOD and SDD in patients who were critically ill. Outcomes included day-28 mortality, length of ICU stay, length of hospital stay, duration of mechanical ventilation, ICU-acquired bacteremia, and prevalence of antibiotic-resistant Gram-negative bacteria. Results were expressed as risk ratio (RR with 95% confidence intervals (CIs, and weighted mean differences (WMDs with 95% CIs. Pooled estimates were performed using a fixed-effects model or random-effects model, depending on the heterogeneity among studies. Results: A total of four RCTs involving 23,822 patients met the inclusion criteria and were included in this meta-analysis. Among patients whose admitting specialty was surgery, cardiothoracic surgery (57.3% and neurosurgery (29.7% were the two main types of surgery being performed. Pooled results showed that SOD had similar effects as SDD in day-28 mortality (RR =1

  6. Geography and genography: prediction of continental origin using randomly selected single nucleotide polymorphisms

    Directory of Open Access Journals (Sweden)

    Ramoni Marco F

    2007-03-01

    Full Text Available Abstract Background Recent studies have shown that when individuals are grouped on the basis of genetic similarity, group membership corresponds closely to continental origin. There has been considerable debate about the implications of these findings in the context of larger debates about race and the extent of genetic variation between groups. Some have argued that clustering according to continental origin demonstrates the existence of significant genetic differences between groups and that these differences may have important implications for differences in health and disease. Others argue that clustering according to continental origin requires the use of large amounts of genetic data or specifically chosen markers and is indicative only of very subtle genetic differences that are unlikely to have biomedical significance. Results We used small numbers of randomly selected single nucleotide polymorphisms (SNPs from the International HapMap Project to train naïve Bayes classifiers for prediction of ancestral continent of origin. Predictive accuracy was tested on two independent data sets. Genetically similar groups should be difficult to distinguish, especially if only a small number of genetic markers are used. The genetic differences between continentally defined groups are sufficiently large that one can accurately predict ancestral continent of origin using only a minute, randomly selected fraction of the genetic variation present in the human genome. Genotype data from only 50 random SNPs was sufficient to predict ancestral continent of origin in our primary test data set with an average accuracy of 95%. Genetic variations informative about ancestry were common and widely distributed throughout the genome. Conclusion Accurate characterization of ancestry is possible using small numbers of randomly selected SNPs. The results presented here show how investigators conducting genetic association studies can use small numbers of arbitrarily

  7. Random forest variable selection in spatial malaria transmission modelling in Mpumalanga Province, South Africa

    Directory of Open Access Journals (Sweden)

    Thandi Kapwata

    2016-11-01

    Full Text Available Malaria is an environmentally driven disease. In order to quantify the spatial variability of malaria transmission, it is imperative to understand the interactions between environmental variables and malaria epidemiology at a micro-geographic level using a novel statistical approach. The random forest (RF statistical learning method, a relatively new variable-importance ranking method, measures the variable importance of potentially influential parameters through the percent increase of the mean squared error. As this value increases, so does the relative importance of the associated variable. The principal aim of this study was to create predictive malaria maps generated using the selected variables based on the RF algorithm in the Ehlanzeni District of Mpumalanga Province, South Africa. From the seven environmental variables used [temperature, lag temperature, rainfall, lag rainfall, humidity, altitude, and the normalized difference vegetation index (NDVI], altitude was identified as the most influential predictor variable due its high selection frequency. It was selected as the top predictor for 4 out of 12 months of the year, followed by NDVI, temperature and lag rainfall, which were each selected twice. The combination of climatic variables that produced the highest prediction accuracy was altitude, NDVI, and temperature. This suggests that these three variables have high predictive capabilities in relation to malaria transmission. Furthermore, it is anticipated that the predictive maps generated from predictions made by the RF algorithm could be used to monitor the progression of malaria and assist in intervention and prevention efforts with respect to malaria.

  8. Distribution of orientation selectivity in recurrent networks of spiking neurons with different random topologies.

    Science.gov (United States)

    Sadeh, Sadra; Rotter, Stefan

    2014-01-01

    Neurons in the primary visual cortex are more or less selective for the orientation of a light bar used for stimulation. A broad distribution of individual grades of orientation selectivity has in fact been reported in all species. A possible reason for emergence of broad distributions is the recurrent network within which the stimulus is being processed. Here we compute the distribution of orientation selectivity in randomly connected model networks that are equipped with different spatial patterns of connectivity. We show that, for a wide variety of connectivity patterns, a linear theory based on firing rates accurately approximates the outcome of direct numerical simulations of networks of spiking neurons. Distance dependent connectivity in networks with a more biologically realistic structure does not compromise our linear analysis, as long as the linearized dynamics, and hence the uniform asynchronous irregular activity state, remain stable. We conclude that linear mechanisms of stimulus processing are indeed responsible for the emergence of orientation selectivity and its distribution in recurrent networks with functionally heterogeneous synaptic connectivity.

  9. Interference-aware random beam selection schemes for spectrum sharing systems

    KAUST Repository

    Abdallah, Mohamed

    2012-10-19

    Spectrum sharing systems have been recently introduced to alleviate the problem of spectrum scarcity by allowing secondary unlicensed networks to share the spectrum with primary licensed networks under acceptable interference levels to the primary users. In this work, we develop interference-aware random beam selection schemes that provide enhanced performance for the secondary network under the condition that the interference observed by the receivers of the primary network is below a predetermined/acceptable value. We consider a secondary link composed of a transmitter equipped with multiple antennas and a single-antenna receiver sharing the same spectrum with a primary link composed of a single-antenna transmitter and a single-antenna receiver. The proposed schemes select a beam, among a set of power-optimized random beams, that maximizes the signal-to-interference-plus-noise ratio (SINR) of the secondary link while satisfying the primary interference constraint for different levels of feedback information describing the interference level at the primary receiver. For the proposed schemes, we develop a statistical analysis for the SINR statistics as well as the capacity and bit error rate (BER) of the secondary link.

  10. Joint random beam and spectrum selection for spectrum sharing systems with partial channel state information

    KAUST Repository

    Abdallah, Mohamed M.

    2013-11-01

    In this work, we develop joint interference-aware random beam and spectrum selection scheme that provide enhanced performance for the secondary network under the condition that the interference observed at the primary receiver is below a predetermined acceptable value. We consider a secondary link composed of a transmitter equipped with multiple antennas and a single-antenna receiver sharing the same spectrum with a set of primary links composed of a single-antenna transmitter and a single-antenna receiver. The proposed schemes jointly select a beam, among a set of power-optimized random beams, as well as the primary spectrum that maximizes the signal-to-interference-plus-noise ratio (SINR) of the secondary link while satisfying the primary interference constraint. In particular, we consider the case where the interference level is described by a q-bit description of its magnitude, whereby we propose a technique to find the optimal quantizer thresholds in a mean square error (MSE) sense. © 2013 IEEE.

  11. Joint random beam and spectrum selection for spectrum sharing systems with partial channel state information

    KAUST Repository

    Abdallah, Mohamed M.; Sayed, Mostafa M.; Alouini, Mohamed-Slim; Qaraqe, Khalid A.

    2013-01-01

    In this work, we develop joint interference-aware random beam and spectrum selection scheme that provide enhanced performance for the secondary network under the condition that the interference observed at the primary receiver is below a predetermined acceptable value. We consider a secondary link composed of a transmitter equipped with multiple antennas and a single-antenna receiver sharing the same spectrum with a set of primary links composed of a single-antenna transmitter and a single-antenna receiver. The proposed schemes jointly select a beam, among a set of power-optimized random beams, as well as the primary spectrum that maximizes the signal-to-interference-plus-noise ratio (SINR) of the secondary link while satisfying the primary interference constraint. In particular, we consider the case where the interference level is described by a q-bit description of its magnitude, whereby we propose a technique to find the optimal quantizer thresholds in a mean square error (MSE) sense. © 2013 IEEE.

  12. Network meta-analysis incorporating randomized controlled trials and non-randomized comparative cohort studies for assessing the safety and effectiveness of medical treatments: challenges and opportunities

    OpenAIRE

    Cameron, Chris; Fireman, Bruce; Hutton, Brian; Clifford, Tammy; Coyle, Doug; Wells, George; Dormuth, Colin R.; Platt, Robert; Toh, Sengwee

    2015-01-01

    Network meta-analysis is increasingly used to allow comparison of multiple treatment alternatives simultaneously, some of which may not have been compared directly in primary research studies. The majority of network meta-analyses published to date have incorporated data from randomized controlled trials (RCTs) only; however, inclusion of non-randomized studies may sometimes be considered. Non-randomized studies can complement RCTs or address some of their limitations, such as short follow-up...

  13. Evaluation of recruitment and selection for specialty training in public health: interim results of a prospective cohort study to measure the predictive validity of the selection process.

    Science.gov (United States)

    Pashayan, Nora; Gray, Selena; Duff, Celia; Parkes, Julie; Williams, David; Patterson, Fiona; Koczwara, Anna; Fisher, Grant; Mason, Brendan W

    2016-06-01

    The recruitment process for public health specialty training includes an assessment centre (AC) with three components, Rust Advanced Numerical Reasoning Appraisal (RANRA), Watson-Glaser Critical Thinking Appraisal (WGCT) and a Situation Judgement Test (SJT), which determines invitation to a selection centre (SC). The scores are combined into a total recruitment (TR) score that determines the offers of appointment. A prospective cohort study using anonymous record linkage to investigate the association between applicant's scores in the recruitment process and registrar's progress through training measured by results of Membership Faculty Public Health (MFPH) examinations and outcomes of the Annual Review of Competence Progression (ARCP). Higher scores in RANRA, WGCT, AC, SC and TR were all significantly associated with higher adjusted odds of passing Part A MFPH exam at the first attempt. Higher scores in AC, SC and TR were significantly associated with passing Part B exam at the first attempt. Higher scores in SJT, AC and SC were significantly associated with satisfactory ARCP outcomes. The current UK national recruitment and selection process for public health specialty training has good predictive validity. The individual components of the process are testing different skills and abilities and together they are providing additive value. © The Author 2015. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Treatment selection in a randomized clinical trial via covariate-specific treatment effect curves.

    Science.gov (United States)

    Ma, Yunbei; Zhou, Xiao-Hua

    2017-02-01

    For time-to-event data in a randomized clinical trial, we proposed two new methods for selecting an optimal treatment for a patient based on the covariate-specific treatment effect curve, which is used to represent the clinical utility of a predictive biomarker. To select an optimal treatment for a patient with a specific biomarker value, we proposed pointwise confidence intervals for each covariate-specific treatment effect curve and the difference between covariate-specific treatment effect curves of two treatments. Furthermore, to select an optimal treatment for a future biomarker-defined subpopulation of patients, we proposed confidence bands for each covariate-specific treatment effect curve and the difference between each pair of covariate-specific treatment effect curve over a fixed interval of biomarker values. We constructed the confidence bands based on a resampling technique. We also conducted simulation studies to evaluate finite-sample properties of the proposed estimation methods. Finally, we illustrated the application of the proposed method in a real-world data set.

  15. Integrated Behavior Therapy for Selective Mutism: a randomized controlled pilot study.

    Science.gov (United States)

    Bergman, R Lindsey; Gonzalez, Araceli; Piacentini, John; Keller, Melody L

    2013-10-01

    To evaluate the feasibility, acceptability, and preliminary efficacy of a novel behavioral intervention for reducing symptoms of selective mutism and increasing functional speech. A total of 21 children ages 4 to 8 with primary selective mutism were randomized to 24 weeks of Integrated Behavior Therapy for Selective Mutism (IBTSM) or a 12-week Waitlist control. Clinical outcomes were assessed using blind independent evaluators, parent-, and teacher-report, and an objective behavioral measure. Treatment recipients completed a three-month follow-up to assess durability of treatment gains. Data indicated increased functional speaking behavior post-treatment as rated by parents and teachers, with a high rate of treatment responders as rated by blind independent evaluators (75%). Conversely, children in the Waitlist comparison group did not experience significant improvements in speaking behaviors. Children who received IBTSM also demonstrated significant improvements in number of words spoken at school compared to baseline, however, significant group differences did not emerge. Treatment recipients also experienced significant reductions in social anxiety per parent, but not teacher, report. Clinical gains were maintained over 3 month follow-up. IBTSM appears to be a promising new intervention that is efficacious in increasing functional speaking behaviors, feasible, and acceptable to parents and teachers. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Two-year Randomized Clinical Trial of Self-etching Adhesives and Selective Enamel Etching.

    Science.gov (United States)

    Pena, C E; Rodrigues, J A; Ely, C; Giannini, M; Reis, A F

    2016-01-01

    The aim of this randomized, controlled prospective clinical trial was to evaluate the clinical effectiveness of restoring noncarious cervical lesions with two self-etching adhesive systems applied with or without selective enamel etching. A one-step self-etching adhesive (Xeno V(+)) and a two-step self-etching system (Clearfil SE Bond) were used. The effectiveness of phosphoric acid selective etching of enamel margins was also evaluated. Fifty-six cavities were restored with each adhesive system and divided into two subgroups (n=28; etch and non-etch). All 112 cavities were restored with the nanohybrid composite Esthet.X HD. The clinical effectiveness of restorations was recorded in terms of retention, marginal integrity, marginal staining, caries recurrence, and postoperative sensitivity after 3, 6, 12, 18, and 24 months (modified United States Public Health Service). The Friedman test detected significant differences only after 18 months for marginal staining in the groups Clearfil SE non-etch (p=0.009) and Xeno V(+) etch (p=0.004). One restoration was lost during the trial (Xeno V(+) etch; p>0.05). Although an increase in marginal staining was recorded for groups Clearfil SE non-etch and Xeno V(+) etch, the clinical effectiveness of restorations was considered acceptable for the single-step and two-step self-etching systems with or without selective enamel etching in this 24-month clinical trial.

  17. Investigating the debate of home birth safety: A critical review of cohort studies focusing on selected infant outcomes.

    Science.gov (United States)

    Elder, Heather R; Alio, Amina P; Fisher, Susan G

    2016-07-01

    There is a debate within the medical community regarding the safety of planned home births. The presumption of increased risk of maternal and infant morbidity and mortality at home due to limited access to life-saving interventions is not clearly supported by research. The aim of the present study was to assess strengths and limitations of the methodological approaches of cohort studies that compare home births with hospital births by focusing on selected infant outcomes. Studies were identified that assess the risk for at least one of three infant outcomes (mortality, Apgar score, and admission to the neonatal intensive care unit [NICU]) of home births compared with hospital births. Fifteen cohort studies were included. Two studies of low-risk births and two including higher risk births found home births to be at an increased risk of neonatal mortality. However, mortality is rare in developed nations and may not be the best measure of safety. When studies focused on low-risk pregnancies, planned birth location, and well-trained birth attendants, there was no difference in neonatal morbidity (Apgar score and NICU admission). Many methodological challenges were identified among these studies. This review contributes to the home birth published work by identifying key strengths and limitations that need to be accounted for in the interpretation of study findings and the development of future studies. Based on this review, the key variables that would strengthen future studies are birth attendant identification, documented planned birth location, and specification of the birth risk level. Uniformity of data collection and minimizing missing data are also critical. © 2016 Japan Academy of Nursing Science.

  18. Selecting Optimal Parameters of Random Linear Network Coding for Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Heide, J; Zhang, Qi; Fitzek, F H P

    2013-01-01

    This work studies how to select optimal code parameters of Random Linear Network Coding (RLNC) in Wireless Sensor Networks (WSNs). With Rateless Deluge [1] the authors proposed to apply Network Coding (NC) for Over-the-Air Programming (OAP) in WSNs, and demonstrated that with NC a significant...... reduction in the number of transmitted packets can be achieved. However, NC introduces additional computations and potentially a non-negligible transmission overhead, both of which depend on the chosen coding parameters. Therefore it is necessary to consider the trade-off that these coding parameters...... present in order to obtain the lowest energy consumption per transmitted bit. This problem is analyzed and suitable coding parameters are determined for the popular Tmote Sky platform. Compared to the use of traditional RLNC, these parameters enable a reduction in the energy spent per bit which grows...

  19. Implications of structural genomics target selection strategies: Pfam5000, whole genome, and random approaches

    Energy Technology Data Exchange (ETDEWEB)

    Chandonia, John-Marc; Brenner, Steven E.

    2004-07-14

    The structural genomics project is an international effort to determine the three-dimensional shapes of all important biological macromolecules, with a primary focus on proteins. Target proteins should be selected according to a strategy which is medically and biologically relevant, of good value, and tractable. As an option to consider, we present the Pfam5000 strategy, which involves selecting the 5000 most important families from the Pfam database as sources for targets. We compare the Pfam5000 strategy to several other proposed strategies that would require similar numbers of targets. These include including complete solution of several small to moderately sized bacterial proteomes, partial coverage of the human proteome, and random selection of approximately 5000 targets from sequenced genomes. We measure the impact that successful implementation of these strategies would have upon structural interpretation of the proteins in Swiss-Prot, TrEMBL, and 131 complete proteomes (including 10 of eukaryotes) from the Proteome Analysis database at EBI. Solving the structures of proteins from the 5000 largest Pfam families would allow accurate fold assignment for approximately 68 percent of all prokaryotic proteins (covering 59 percent of residues) and 61 percent of eukaryotic proteins (40 percent of residues). More fine-grained coverage which would allow accurate modeling of these proteins would require an order of magnitude more targets. The Pfam5000 strategy may be modified in several ways, for example to focus on larger families, bacterial sequences, or eukaryotic sequences; as long as secondary consideration is given to large families within Pfam, coverage results vary only slightly. In contrast, focusing structural genomics on a single tractable genome would have only a limited impact in structural knowledge of other proteomes: a significant fraction (about 30-40 percent of the proteins, and 40-60 percent of the residues) of each proteome is classified in small

  20. A prospective randomized cohort study evaluating 3 weeks vs 6 weeks of oral antibiotic treatment in the setting of "maximal medical therapy" for chronic rhinosinusitis.

    Science.gov (United States)

    Sreenath, Satyan B; Taylor, Robert J; Miller, Justin D; Ambrose, Emily C; Rawal, Rounak B; Ebert, Charles S; Senior, Brent A; Zanation, Adam M

    2015-09-01

    Surprisingly, little literature exists evaluating the optimal duration of antibiotic treatment in "maximal medical therapy" for chronic rhinosinusitis (CRS). As such, we investigated whether 3 weeks vs 6 weeks of antibiotic therapy resulted in significant differences in clinical response. A prospective, randomized cohort study was performed with patients assigned to 3-week or 6-week cohorts. Our primary outcome was failure of "maximal medical therapy" and surgical recommendation. Secondary outcomes included changes in pretherapy and posttherapy scores for the Rhinosinusitis Disability Index (RSDI), Chronic Sinusitis Survey (CSS), and computed tomography (CT)-based Lund-Mackay (LM) evaluation. Analyses were substratified based on presence of nasal polyps. Forty patients were randomized to the 3-week or 6-week treatment cohorts, with near-complete clinical follow-up achieved. No significant difference was found between the proportion of patients who failed medical therapy and were deemed surgical candidates between the 2 cohorts (71% vs 68%, p = 1.000). No significant difference was found in the change of RSDI or CSS scores in the 3 vs 6 weeks of treatment groups (mean ± standard error of the mean [SEM]; RSDI: 9.62 ± 4.14 vs 1.53 ± 4.01, p = 0.868; CSS: 5.75 ± 4.36 vs 9.65 ± 5.34, p = 0.573). Last, no significant difference was found in the change of LM scores (3.35 ± 1.11 vs 1.53 ± 0.81, p = 0.829). Based on this data, there is little difference in clinical outcomes between 3 weeks vs 6 weeks of antibiotic treatment as part of "maximal medical therapy" for CRS. Increased duration of antibiotic treatment theoretically may increase risk from side effects and creates higher healthcare costs. © 2015 ARS-AAOA, LLC.

  1. Day-ahead load forecast using random forest and expert input selection

    International Nuclear Information System (INIS)

    Lahouar, A.; Ben Hadj Slama, J.

    2015-01-01

    Highlights: • A model based on random forests for short term load forecast is proposed. • An expert feature selection is added to refine inputs. • Special attention is paid to customers behavior, load profile and special holidays. • The model is flexible and able to handle complex load signal. • A technical comparison is performed to assess the forecast accuracy. - Abstract: The electrical load forecast is getting more and more important in recent years due to the electricity market deregulation and integration of renewable resources. To overcome the incoming challenges and ensure accurate power prediction for different time horizons, sophisticated intelligent methods are elaborated. Utilization of intelligent forecast algorithms is among main characteristics of smart grids, and is an efficient tool to face uncertainty. Several crucial tasks of power operators such as load dispatch rely on the short term forecast, thus it should be as accurate as possible. To this end, this paper proposes a short term load predictor, able to forecast the next 24 h of load. Using random forest, characterized by immunity to parameter variations and internal cross validation, the model is constructed following an online learning process. The inputs are refined by expert feature selection using a set of if–then rules, in order to include the own user specifications about the country weather or market, and to generalize the forecast ability. The proposed approach is tested through a real historical set from the Tunisian Power Company, and the simulation shows accurate and satisfactory results for one day in advance, with an average error exceeding rarely 2.3%. The model is validated for regular working days and weekends, and special attention is paid to moving holidays, following non Gregorian calendar

  2. Field-based random sampling without a sampling frame: control selection for a case-control study in rural Africa.

    Science.gov (United States)

    Crampin, A C; Mwinuka, V; Malema, S S; Glynn, J R; Fine, P E

    2001-01-01

    Selection bias, particularly of controls, is common in case-control studies and may materially affect the results. Methods of control selection should be tailored both for the risk factors and disease under investigation and for the population being studied. We present here a control selection method devised for a case-control study of tuberculosis in rural Africa (Karonga, northern Malawi) that selects an age/sex frequency-matched random sample of the population, with a geographical distribution in proportion to the population density. We also present an audit of the selection process, and discuss the potential of this method in other settings.

  3. Longitudinal analysis of the strengths and difficulties questionnaire scores of the Millennium Cohort Study children in England using M-quantile random-effects regression.

    Science.gov (United States)

    Tzavidis, Nikos; Salvati, Nicola; Schmid, Timo; Flouri, Eirini; Midouhas, Emily

    2016-02-01

    Multilevel modelling is a popular approach for longitudinal data analysis. Statistical models conventionally target a parameter at the centre of a distribution. However, when the distribution of the data is asymmetric, modelling other location parameters, e.g. percentiles, may be more informative. We present a new approach, M -quantile random-effects regression, for modelling multilevel data. The proposed method is used for modelling location parameters of the distribution of the strengths and difficulties questionnaire scores of children in England who participate in the Millennium Cohort Study. Quantile mixed models are also considered. The analyses offer insights to child psychologists about the differential effects of risk factors on children's outcomes.

  4. Modified random hinge transport mechanics and multiple scattering step-size selection in EGS5

    International Nuclear Information System (INIS)

    Wilderman, S.J.; Bielajew, A.F.

    2005-01-01

    The new transport mechanics in EGS5 allows for significantly longer electron transport step sizes and hence shorter computation times than required for identical problems in EGS4. But as with all Monte Carlo electron transport algorithms, certain classes of problems exhibit step-size dependencies even when operating within recommended ranges, sometimes making selection of step-sizes a daunting task for novice users. Further contributing to this problem, because of the decoupling of multiple scattering and continuous energy loss in the dual random hinge transport mechanics of EGS5, there are two independent step sizes in EGS5, one for multiple scattering and one for continuous energy loss, each of which influences speed and accuracy in a different manner. Further, whereas EGS4 used a single value of fractional energy loss (ESTEPE) to determine step sizes at all energies, to increase performance by decreasing the amount of effort expended simulating lower energy particles, EGS5 permits the fractional energy loss values which are used to determine both the multiple scattering and continuous energy loss step sizes to vary with energy. This results in requiring the user to specify four fractional energy loss values when optimizing computations for speed. Thus, in order to simplify step-size selection and to mitigate step-size dependencies, a method has been devised to automatically optimize step-size selection based on a single material dependent input related to the size of problem tally region. In this paper we discuss the new transport mechanics in EGS5 and describe the automatic step-size optimization algorithm. (author)

  5. Perceived neighborhood partner availability, partner selection, and risk for sexually transmitted infections within a cohort of adolescent females.

    Science.gov (United States)

    Matson, Pamela A; Chung, Shang-En; Ellen, Jonathan M

    2014-07-01

    This research examined the association between a novel measure of perceived partner availability and discordance between ideal and actual partner characteristics as well as trajectories of ideal partner preferences and perceptions of partner availability over time. A clinic-recruited cohort of adolescent females (N = 92), aged 1619 years, were interviewed quarterly for 12 months using audio computer-assisted self-interview. Participants ranked the importance of characteristics for their ideal main sex partner and then reported on these characteristics for their current main partner. Participants reported on perceptions of availability of ideal sex partners in their neighborhood. Paired t-tests examined discordance between ideal and actual partner characteristics. Random-intercept regression models examined repeated measures. Actual partner ratings were lower than ideal partner preferences for fidelity, equaled ideal preferences for emotional support and exceeded ideal preferences for social/economic status and physical attractiveness. Discordance on emotional support and social/economic status was associated with sex partner concurrency. Participants perceived low availability of ideal sex partners. Those who perceived more availability were less likely to be ideal/actual discordant on fidelity [OR = .88, 95% CI: .78, 1.0]. Neither ideal partner preferences nor perceptions of partner availability changed over 12 months. Current main sex partners met or exceeded ideal partner preferences in all domains except fidelity. If emotional needs are met, adolescents may tolerate partner concurrency in areas of limited partner pools. Urban adolescent females who perceive low availability may be at increased risk for sexually transmitted infection (STI) because they may be more likely to have nonmonogamous partners. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  6. The adverse effect of selective cyclooxygenase-2 inhibitor on random skin flap survival in rats.

    Directory of Open Access Journals (Sweden)

    Haiyong Ren

    Full Text Available BACKGROUND: Cyclooxygenase-2(COX-2 inhibitors provide desired analgesic effects after injury or surgery, but evidences suggested they also attenuate wound healing. The study is to investigate the effect of COX-2 inhibitor on random skin flap survival. METHODS: The McFarlane flap model was established in 40 rats and evaluated within two groups, each group gave the same volume of Parecoxib and saline injection for 7 days. The necrotic area of the flap was measured, the specimens of the flap were stained with haematoxylin-eosin(HE for histologic analysis. Immunohistochemical staining was performed to analyse the level of VEGF and COX-2 . RESULTS: 7 days after operation, the flap necrotic area ratio in study group (66.65 ± 2.81% was significantly enlarged than that of the control group(48.81 ± 2.33%(P <0.01. Histological analysis demonstrated angiogenesis with mean vessel density per mm(2 being lower in study group (15.4 ± 4.4 than in control group (27.2 ± 4.1 (P <0.05. To evaluate the expression of COX-2 and VEGF protein in the intermediate area II in the two groups by immunohistochemistry test .The expression of COX-2 in study group was (1022.45 ± 153.1, and in control group was (2638.05 ± 132.2 (P <0.01. The expression of VEGF in the study and control groups were (2779.45 ± 472.0 vs (4938.05 ± 123.6(P <0.01.In the COX-2 inhibitor group, the expressions of COX-2 and VEGF protein were remarkably down-regulated as compared with the control group. CONCLUSION: Selective COX-2 inhibitor had adverse effect on random skin flap survival. Suppression of neovascularization induced by low level of VEGF was supposed to be the biological mechanism.

  7. Application of random coherence order selection in gradient-enhanced multidimensional NMR

    International Nuclear Information System (INIS)

    Bostock, Mark J.; Nietlispach, Daniel

    2016-01-01

    Development of multidimensional NMR is essential to many applications, for example in high resolution structural studies of biomolecules. Multidimensional techniques enable separation of NMR signals over several dimensions, improving signal resolution, whilst also allowing identification of new connectivities. However, these advantages come at a significant cost. The Fourier transform theorem requires acquisition of a grid of regularly spaced points to satisfy the Nyquist criterion, while frequency discrimination and acquisition of a pure phase spectrum require acquisition of both quadrature components for each time point in every indirect (non-acquisition) dimension, adding a factor of 2 N -1 to the number of free- induction decays which must be acquired, where N is the number of dimensions. Compressed sensing (CS) ℓ 1 -norm minimisation in combination with non-uniform sampling (NUS) has been shown to be extremely successful in overcoming the Nyquist criterion. Previously, maximum entropy reconstruction has also been used to overcome the limitation of frequency discrimination, processing data acquired with only one quadrature component at a given time interval, known as random phase detection (RPD), allowing a factor of two reduction in the number of points for each indirect dimension (Maciejewski et al. 2011 PNAS 108 16640). However, whilst this approach can be easily applied in situations where the quadrature components are acquired as amplitude modulated data, the same principle is not easily extended to phase modulated (P-/N-type) experiments where data is acquired in the form exp (iωt) or exp (-iωt), and which make up many of the multidimensional experiments used in modern NMR. Here we demonstrate a modification of the CS ℓ 1 -norm approach to allow random coherence order selection (RCS) for phase modulated experiments; we generalise the nomenclature for RCS and RPD as random quadrature detection (RQD). With this method, the power of RQD can be extended

  8. Random genetic drift, natural selection, and noise in human cranial evolution.

    Science.gov (United States)

    Roseman, Charles C

    2016-08-01

    This study assesses the extent to which relationships among groups complicate comparative studies of adaptation in recent human cranial variation and the extent to which departures from neutral additive models of evolution hinder the reconstruction of population relationships among groups using cranial morphology. Using a maximum likelihood evolutionary model fitting approach and a mixed population genomic and cranial data set, I evaluate the relative fits of several widely used models of human cranial evolution. Moreover, I compare the goodness of fit of models of cranial evolution constrained by genomic variation to test hypotheses about population specific departures from neutrality. Models from population genomics are much better fits to cranial variation than are traditional models from comparative human biology. There is not enough evolutionary information in the cranium to reconstruct much of recent human evolution but the influence of population history on cranial variation is strong enough to cause comparative studies of adaptation serious difficulties. Deviations from a model of random genetic drift along a tree-like population history show the importance of environmental effects, gene flow, and/or natural selection on human cranial variation. Moreover, there is a strong signal of the effect of natural selection or an environmental factor on a group of humans from Siberia. The evolution of the human cranium is complex and no one evolutionary process has prevailed at the expense of all others. A holistic unification of phenome, genome, and environmental context, gives us a strong point of purchase on these problems, which is unavailable to any one traditional approach alone. Am J Phys Anthropol 160:582-592, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  9. Multi-Label Learning via Random Label Selection for Protein Subcellular Multi-Locations Prediction.

    Science.gov (United States)

    Wang, Xiao; Li, Guo-Zheng

    2013-03-12

    Prediction of protein subcellular localization is an important but challenging problem, particularly when proteins may simultaneously exist at, or move between, two or more different subcellular location sites. Most of the existing protein subcellular localization methods are only used to deal with the single-location proteins. In the past few years, only a few methods have been proposed to tackle proteins with multiple locations. However, they only adopt a simple strategy, that is, transforming the multi-location proteins to multiple proteins with single location, which doesn't take correlations among different subcellular locations into account. In this paper, a novel method named RALS (multi-label learning via RAndom Label Selection), is proposed to learn from multi-location proteins in an effective and efficient way. Through five-fold cross validation test on a benchmark dataset, we demonstrate our proposed method with consideration of label correlations obviously outperforms the baseline BR method without consideration of label correlations, indicating correlations among different subcellular locations really exist and contribute to improvement of prediction performance. Experimental results on two benchmark datasets also show that our proposed methods achieve significantly higher performance than some other state-of-the-art methods in predicting subcellular multi-locations of proteins. The prediction web server is available at http://levis.tongji.edu.cn:8080/bioinfo/MLPred-Euk/ for the public usage.

  10. Policy-into-practice for rheumatoid arthritis: randomized controlled trial and cohort study of e-learning targeting improved physiotherapy management.

    Science.gov (United States)

    Fary, Robyn E; Slater, Helen; Chua, Jason; Ranelli, Sonia; Chan, Madelynn; Briggs, Andrew M

    2015-07-01

    To examine the effectiveness of a physiotherapy-specific, web-based e-learning platform, "RAP-el," in best-practice management of rheumatoid arthritis (RA) using a single-blind, randomized controlled trial (RCT) and prospective cohort study. Australian-registered physiotherapists were electronically randomized into intervention and control groups. The intervention group accessed RAP-eL over 4 weeks. Change in self-reported confidence in knowledge and skills was compared between groups at the end of the RCT using linear regression conditioned for baseline scores by a blinded assessor, using intent-to-treat analysis. Secondary outcomes included physiotherapists' satisfaction with RA management and responses to RA-relevant clinical statements and practice-relevant vignettes. Retention was evaluated in a cohort study 8 weeks after the RCT. Eighty physiotherapists were randomized into the intervention and 79 into the control groups. Fifty-six and 48, respectively, provided baseline data. Significant between-group differences were observed for change in confidence in knowledge (mean difference 8.51; 95% confidence interval [95% CI] 6.29, 10.73; effect size 1.62) and skills (mean difference 7.26; 95% CI 5.1, 9.4; effect size 1.54), with the intervention group performing better. Satisfaction in ability to manage RA, 4 of the 6 clinical statements, and responses to vignettes demonstrated significant improvement in the intervention group. Although 8-week scores showed declines in most outcomes, their clinical significance remains uncertain. RAP-eL can improve self-reported confidence, likely practice behaviors and satisfaction in physiotherapists' ability to manage people with RA, and improve their clinical knowledge in several areas of best-practice RA management in the short term. © 2015, American College of Rheumatology.

  11. Advanced Choice Employment (ACE) factors influencing PGY-1 workplace selection and future career intentions of a cohort of doctors in Waikato.

    Science.gov (United States)

    Clark, Helen; de Beer, Wayne; Gibbons, Veronique

    2017-01-27

    To assess whether or not a sample of PGY-1 doctors in the Waikato region remained satisfied with the ACE system for employment 12 years after its inception. An anonymous paper-based survey was completed by a cohort (n=60) of 2015 and 2016 PGY-1 doctors based at the Waikato DHB. Questions were based around reasons for selecting the DHB, satisfaction with the ACE process and future career intentions. Overall satisfaction with the ACE selection process was reasonable (63%). Over 60% of the 2015 and 2016 cohorts chose Waikato as their first choice DHB, and of those, over 90% intended to carry on through to at least PGY2 level at the DHB. An overwhelming majority (93-96%) intended to continue practicing in New Zealand. Consistent trends were observed across the two cohorts in regards to their reasons for selecting the DHB, satisfaction with ACE and future intentions, with some differences observed with familial background and interest in pursuing hospital-based specialties. Our findings suggest that ACE remains a satisfactory recruiting system for postgraduate junior doctors, however, motives around initial DHB selection and future vocational intentions remain unclear and warrant further investigation.

  12. Differential privacy-based evaporative cooling feature selection and classification with relief-F and random forests.

    Science.gov (United States)

    Le, Trang T; Simmons, W Kyle; Misaki, Masaya; Bodurka, Jerzy; White, Bill C; Savitz, Jonathan; McKinney, Brett A

    2017-09-15

    Classification of individuals into disease or clinical categories from high-dimensional biological data with low prediction error is an important challenge of statistical learning in bioinformatics. Feature selection can improve classification accuracy but must be incorporated carefully into cross-validation to avoid overfitting. Recently, feature selection methods based on differential privacy, such as differentially private random forests and reusable holdout sets, have been proposed. However, for domains such as bioinformatics, where the number of features is much larger than the number of observations p≫n , these differential privacy methods are susceptible to overfitting. We introduce private Evaporative Cooling, a stochastic privacy-preserving machine learning algorithm that uses Relief-F for feature selection and random forest for privacy preserving classification that also prevents overfitting. We relate the privacy-preserving threshold mechanism to a thermodynamic Maxwell-Boltzmann distribution, where the temperature represents the privacy threshold. We use the thermal statistical physics concept of Evaporative Cooling of atomic gases to perform backward stepwise privacy-preserving feature selection. On simulated data with main effects and statistical interactions, we compare accuracies on holdout and validation sets for three privacy-preserving methods: the reusable holdout, reusable holdout with random forest, and private Evaporative Cooling, which uses Relief-F feature selection and random forest classification. In simulations where interactions exist between attributes, private Evaporative Cooling provides higher classification accuracy without overfitting based on an independent validation set. In simulations without interactions, thresholdout with random forest and private Evaporative Cooling give comparable accuracies. We also apply these privacy methods to human brain resting-state fMRI data from a study of major depressive disorder. Code

  13. Bayesian dose selection design for a binary outcome using restricted response adaptive randomization.

    Science.gov (United States)

    Meinzer, Caitlyn; Martin, Renee; Suarez, Jose I

    2017-09-08

    In phase II trials, the most efficacious dose is usually not known. Moreover, given limited resources, it is difficult to robustly identify a dose while also testing for a signal of efficacy that would support a phase III trial. Recent designs have sought to be more efficient by exploring multiple doses through the use of adaptive strategies. However, the added flexibility may potentially increase the risk of making incorrect assumptions and reduce the total amount of information available across the dose range as a function of imbalanced sample size. To balance these challenges, a novel placebo-controlled design is presented in which a restricted Bayesian response adaptive randomization (RAR) is used to allocate a majority of subjects to the optimal dose of active drug, defined as the dose with the lowest probability of poor outcome. However, the allocation between subjects who receive active drug or placebo is held constant to retain the maximum possible power for a hypothesis test of overall efficacy comparing the optimal dose to placebo. The design properties and optimization of the design are presented in the context of a phase II trial for subarachnoid hemorrhage. For a fixed total sample size, a trade-off exists between the ability to select the optimal dose and the probability of rejecting the null hypothesis. This relationship is modified by the allocation ratio between active and control subjects, the choice of RAR algorithm, and the number of subjects allocated to an initial fixed allocation period. While a responsive RAR algorithm improves the ability to select the correct dose, there is an increased risk of assigning more subjects to a worse arm as a function of ephemeral trends in the data. A subarachnoid treatment trial is used to illustrate how this design can be customized for specific objectives and available data. Bayesian adaptive designs are a flexible approach to addressing multiple questions surrounding the optimal dose for treatment efficacy

  14. Using ArcMap, Google Earth, and Global Positioning Systems to select and locate random households in rural Haiti.

    Science.gov (United States)

    Wampler, Peter J; Rediske, Richard R; Molla, Azizur R

    2013-01-18

    A remote sensing technique was developed which combines a Geographic Information System (GIS); Google Earth, and Microsoft Excel to identify home locations for a random sample of households in rural Haiti. The method was used to select homes for ethnographic and water quality research in a region of rural Haiti located within 9 km of a local hospital and source of health education in Deschapelles, Haiti. The technique does not require access to governmental records or ground based surveys to collect household location data and can be performed in a rapid, cost-effective manner. The random selection of households and the location of these households during field surveys were accomplished using GIS, Google Earth, Microsoft Excel, and handheld Garmin GPSmap 76CSx GPS units. Homes were identified and mapped in Google Earth, exported to ArcMap 10.0, and a random list of homes was generated using Microsoft Excel which was then loaded onto handheld GPS units for field location. The development and use of a remote sensing method was essential to the selection and location of random households. A total of 537 homes initially were mapped and a randomized subset of 96 was identified as potential survey locations. Over 96% of the homes mapped using Google Earth imagery were correctly identified as occupied dwellings. Only 3.6% of the occupants of mapped homes visited declined to be interviewed. 16.4% of the homes visited were not occupied at the time of the visit due to work away from the home or market days. A total of 55 households were located using this method during the 10 days of fieldwork in May and June of 2012. The method used to generate and field locate random homes for surveys and water sampling was an effective means of selecting random households in a rural environment lacking geolocation infrastructure. The success rate for locating households using a handheld GPS was excellent and only rarely was local knowledge required to identify and locate households. This

  15. Using ArcMap, Google Earth, and Global Positioning Systems to select and locate random households in rural Haiti

    Directory of Open Access Journals (Sweden)

    Wampler Peter J

    2013-01-01

    Full Text Available Abstract Background A remote sensing technique was developed which combines a Geographic Information System (GIS; Google Earth, and Microsoft Excel to identify home locations for a random sample of households in rural Haiti. The method was used to select homes for ethnographic and water quality research in a region of rural Haiti located within 9 km of a local hospital and source of health education in Deschapelles, Haiti. The technique does not require access to governmental records or ground based surveys to collect household location data and can be performed in a rapid, cost-effective manner. Methods The random selection of households and the location of these households during field surveys were accomplished using GIS, Google Earth, Microsoft Excel, and handheld Garmin GPSmap 76CSx GPS units. Homes were identified and mapped in Google Earth, exported to ArcMap 10.0, and a random list of homes was generated using Microsoft Excel which was then loaded onto handheld GPS units for field location. The development and use of a remote sensing method was essential to the selection and location of random households. Results A total of 537 homes initially were mapped and a randomized subset of 96 was identified as potential survey locations. Over 96% of the homes mapped using Google Earth imagery were correctly identified as occupied dwellings. Only 3.6% of the occupants of mapped homes visited declined to be interviewed. 16.4% of the homes visited were not occupied at the time of the visit due to work away from the home or market days. A total of 55 households were located using this method during the 10 days of fieldwork in May and June of 2012. Conclusions The method used to generate and field locate random homes for surveys and water sampling was an effective means of selecting random households in a rural environment lacking geolocation infrastructure. The success rate for locating households using a handheld GPS was excellent and only

  16. Moderate alcohol consumption, adiponectin, inflammation and type 2 diabetes risk : prospective cohort studies and randomized crossover trials

    OpenAIRE

    Joosten, M.M.

    2011-01-01

    Background: Moderate alcohol consumption has been associated with a lower risk of type 2 diabetes in various populations. However, the underlying mechanisms are not entirely clear. The aims of this thesis were 1) to substantiate the evidence of the association between alcohol consumption and type 2 diabetes in observational research and 2) to examine physiological mechanisms in randomized trials with specific attention to adiponectin, inflammation and insulin sensitivity which may mediate the...

  17. Peculiarities of the statistics of spectrally selected fluorescence radiation in laser-pumped dye-doped random media

    Science.gov (United States)

    Yuvchenko, S. A.; Ushakova, E. V.; Pavlova, M. V.; Alonova, M. V.; Zimnyakov, D. A.

    2018-04-01

    We consider the practical realization of a new optical probe method of the random media which is defined as the reference-free path length interferometry with the intensity moments analysis. A peculiarity in the statistics of the spectrally selected fluorescence radiation in laser-pumped dye-doped random medium is discussed. Previously established correlations between the second- and the third-order moments of the intensity fluctuations in the random interference patterns, the coherence function of the probe radiation, and the path difference probability density for the interfering partial waves in the medium are confirmed. The correlations were verified using the statistical analysis of the spectrally selected fluorescence radiation emitted by a laser-pumped dye-doped random medium. Water solution of Rhodamine 6G was applied as the doping fluorescent agent for the ensembles of the densely packed silica grains, which were pumped by the 532 nm radiation of a solid state laser. The spectrum of the mean path length for a random medium was reconstructed.

  18. Long-term effects of weight reduction on the severity of psoriasis in a cohort derived from a randomized trial

    DEFF Research Database (Denmark)

    Jensen, Peter; Christensen, Robin; Zachariae, Claus

    2016-01-01

    randomized phase with an LED for 8 wk and 8 wk of normal food intake combined with 2 LED products/d, followed by a 48-wk period of weight maintenance with the latter diet. After the randomization phase, the control group received the same 8 + 8-wk LED intervention, and all patients were then followed for 48...... who were allocated to a control group or a low-energy diet (LED) group. Here we followed the participants for an additional 48-wk period. In total, 56 patients with psoriasis [mean ± SD body mass index (in kg/m(2)): 34.4 ± 5.3] underwent a 64-wk weight-loss program consisting of an initial 16-wk...... wk while on the weight-loss maintenance diet. The main outcome was the Psoriasis Area and Severity Index (PASI), and secondary outcome was the Dermatology Life Quality Index (DLQI). RESULTS: For the present study, 56 patients were eligible, 38 agreed to participate, and 32 completed. After the 16-wk...

  19. Academic and Behavioral Design Parameters for Cluster Randomized Trials in Kindergarten: An Analysis of the Early Childhood Longitudinal Study 2011 Kindergarten Cohort (ECLS-K 2011).

    Science.gov (United States)

    Hedberg, E C

    2016-06-28

    There is an increased focus on randomized trials for proximal behavioral outcomes in early childhood research. However, planning sample sizes for such designs requires extant information on the size of effect, variance decomposition, and effectiveness of covariates. The purpose of this article is to employ a recent large representative sample of early childhood longitudinal study kindergartners to estimate design parameters for use in planning cluster randomized trials. A secondary objective is to compare the results of math and reading with the previous kindergartner cohort of 1999. For each measure, fall-spring gains in effect size units are calculated. In addition, multilevel models are fit to estimate variance components that are used to calculate intraclass correlations (ICCs) and R 2 statistics. The implications of the reported parameters are summarized in tables of required school sample sizes to detect small effects. The outcomes include information about student scores regarding learning behaviors, general behaviors, and academic abilities. Aside from math and reading, there were small gains in these measures from fall to spring, leading to effect sizes between about .1 and .2. In addition, the nonacademic ICCs are smaller than the academic ICCs but are still nontrivial. Use of a pretest covariate is generally effective in reducing the required sample size in power analyses. The ICCs for math and reading are smaller for the current sample compared with the 1999 sample. © The Author(s) 2016.

  20. An empirically derived dietary pattern associated with breast cancer risk is validated in a nested case-control cohort from a randomized primary prevention trial.

    Science.gov (United States)

    Hidaka, Brandon H; Kimler, Bruce F; Fabian, Carol J; Carlson, Susan E

    2017-02-01

    We reported an association between cytologic atypia, a reversible biomarker of breast cancer risk, and lower omega-3/omega-6 fatty acid ratio in blood and breast tissue. Our goal was to develop and validate a dietary pattern index in this high-risk sample of U.S. women, and test its capacity to predict incidence in a nested case-control cohort of Canadian women from a randomized trial of a low-fat dietary intervention for primary prevention of breast cancer. Food intake was measured by food frequency questionnaire in the U.S. sample (n = 65) and multiple dietary recalls in the Canadian sample (n = 220 cases; 440 controls). Principal component analysis identified a dietary pattern associated with atypia. We measured differences among dietary pattern tertiles in (a) fatty acid composition in blood lipids and breast tissue in the U.S. sample, and (b) risk of breast cancer subtypes in the Canadian cohort. Registered under ClinicalTrials.gov Identifier: NCT00148057. A Modern diet was characterized as consuming more grains, dairy, and sugar and less vegetables, fish and poultry; these women had lower tissue omega-3 fatty acids and higher omega-6 and trans fatty acids. The low-fat intervention increased the likelihood of a Modern diet after randomization. A Modern diet at baseline and post-randomization was associated with estrogen-receptor negative (ER-) breast cancer risk among those at least 160 cm tall. A Traditional diet (the reciprocal of Modern) at baseline was associated with lower ER-positive (ER+) risk in the comparison group, but not the low-fat intervention group. A Modern diet (high in grains, dairy, and sugar and low in vegetables, fish, and poultry) is associated with ER- breast cancer risk among taller women. Recommending dietary fat reduction may have untoward effects on breast cancer risk. Copyright © 2016 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.

  1. The basic science and mathematics of random mutation and natural selection.

    Science.gov (United States)

    Kleinman, Alan

    2014-12-20

    The mutation and natural selection phenomenon can and often does cause the failure of antimicrobial, herbicidal, pesticide and cancer treatments selection pressures. This phenomenon operates in a mathematically predictable behavior, which when understood leads to approaches to reduce and prevent the failure of the use of these selection pressures. The mathematical behavior of mutation and selection is derived using the principles given by probability theory. The derivation of the equations describing the mutation and selection phenomenon is carried out in the context of an empirical example. Copyright © 2014 John Wiley & Sons, Ltd.

  2. Selecting for Fast Protein-Protein Association As Demonstrated on a Random TEM1 Yeast Library Binding BLIP.

    Science.gov (United States)

    Cohen-Khait, Ruth; Schreiber, Gideon

    2018-04-27

    Protein-protein interactions mediate the vast majority of cellular processes. Though protein interactions obey basic chemical principles also within the cell, the in vivo physiological environment may not allow for equilibrium to be reached. Thus, in vitro measured thermodynamic affinity may not provide a complete picture of protein interactions in the biological context. Binding kinetics composed of the association and dissociation rate constants are relevant and important in the cell. Therefore, changes in protein-protein interaction kinetics have a significant impact on the in vivo activity of the proteins. The common protocol for the selection of tighter binders from a mutant library selects for protein complexes with slower dissociation rate constants. Here we describe a method to specifically select for variants with faster association rate constants by using pre-equilibrium selection, starting from a large random library. Toward this end, we refine the selection conditions of a TEM1-β-lactamase library against its natural nanomolar affinity binder β-lactamase inhibitor protein (BLIP). The optimal selection conditions depend on the ligand concentration and on the incubation time. In addition, we show that a second sort of the library helps to separate signal from noise, resulting in a higher percent of faster binders in the selected library. Fast associating protein variants are of particular interest for drug development and other biotechnological applications.

  3. Research Data Explorer: Lessons Learned in Design and Development of Context-based Cohort Definition and Selection.

    Science.gov (United States)

    Wilcox, Adam; Vawdrey, David; Weng, Chunhua; Velez, Mark; Bakken, Suzanne

    2015-01-01

    Research Data eXplorer (RedX) was designed to support self-service research data queries and cohort identification from clinical research databases. The primary innovation of RedX was the electronic health record view of patient data, to provide better contextual understanding for non-technical users in building complex data queries. The design of RedX around this need identified multiple functions that would use individual patient views to better understand population-based data, and vice-versa. During development, the more necessary and valuable components of RedX were refined, leading to a functional self-service query and cohort identification tool. However, with the improved capabilities and extensibility of other applications for data querying and navigation, our long-term implementation and dissemination plans have moved towards consolidation and alignment of RedX functions as enhancements in these other initiatives.

  4. r2VIM: A new variable selection method for random forests in genome-wide association studies.

    Science.gov (United States)

    Szymczak, Silke; Holzinger, Emily; Dasgupta, Abhijit; Malley, James D; Molloy, Anne M; Mills, James L; Brody, Lawrence C; Stambolian, Dwight; Bailey-Wilson, Joan E

    2016-01-01

    Machine learning methods and in particular random forests (RFs) are a promising alternative to standard single SNP analyses in genome-wide association studies (GWAS). RFs provide variable importance measures (VIMs) to rank SNPs according to their predictive power. However, in contrast to the established genome-wide significance threshold, no clear criteria exist to determine how many SNPs should be selected for downstream analyses. We propose a new variable selection approach, recurrent relative variable importance measure (r2VIM). Importance values are calculated relative to an observed minimal importance score for several runs of RF and only SNPs with large relative VIMs in all of the runs are selected as important. Evaluations on simulated GWAS data show that the new method controls the number of false-positives under the null hypothesis. Under a simple alternative hypothesis with several independent main effects it is only slightly less powerful than logistic regression. In an experimental GWAS data set, the same strong signal is identified while the approach selects none of the SNPs in an underpowered GWAS. The novel variable selection method r2VIM is a promising extension to standard RF for objectively selecting relevant SNPs in GWAS while controlling the number of false-positive results.

  5. Physical self-concept changes in a selective sport high school: a longitudinal cohort-sequence analysis of the big-fish-little-pond effect.

    Science.gov (United States)

    Marsh, Herbert W; Morin, Alexandre J; Parker, Philip D

    2015-04-01

    Elite athletes and nonathletes (N = 1,268) attending the same selective sport high school (4 high school age cohorts, grades 7-10, mean ages varying from 10.9 to 14.1) completed the same physical self-concept instrument 4 times over a 2-year period (multiple waves). We introduce a latent cohort-sequence analysis that provides a stronger basis for assessing developmental stability/change than either cross-sectional (multicohort, single occasion) or longitudinal (single-cohort, multiple occasion) designs, allowing us to evaluate latent means across 10 waves spanning a 5-year period (grades 7-11), although each participant contributed data for only 4 waves, spanning 2 of the 5 years. Consistent with the frame-of-reference effects embodied in the big-fish-little-pond effect (BFLPE), physical self-concepts at the start of high school were much higher for elite athletes than for nonathlete classmates, but the differences declined over time so that by the end of high school there were no differences in the 2 groups. Gender differences in favor of males had a negative linear and quadratic trajectory over time, but the consistently smaller gender differences for athletes than for nonathletes did not vary with time.

  6. Can marital selection explain the differences in health between married and divorced people? From a longitudinal study of a British birth cohort.

    Science.gov (United States)

    Cheung, Y B

    1998-03-01

    In view of the rising divorce rates, the impact of divorce on health has an increasing importance in public health. The differentials in health between the married and the divorced may be explained by 'marital selection' and 'marital protection'. Using longitudinal data from a study of the 1958 British birth cohort, factors that select people into divorce were identified from the areas of socio-economic status, health, and attractiveness, which included physical attractiveness, health-related behaviour and temperament. Evidence for both positive and adverse selection is found. The different sets of selection factors for females and males appear to be in line with gender role expectations. The health differentials between married and divorced men were weak and can be explained away by the selection factors. Having controlled for the selection effects, there were still significant associations between divorce and physical and psychological health in women. Though these unexplained differentials cannot be definitely interpreted as the consequences of marital dissolution, this interpretation remains plausible.

  7. Feature selection and classification of mechanical fault of an induction motor using random forest classifier

    OpenAIRE

    Patel, Raj Kumar; Giri, V.K.

    2016-01-01

    Fault detection and diagnosis is the most important technology in condition-based maintenance (CBM) system for rotating machinery. This paper experimentally explores the development of a random forest (RF) classifier, a recently emerged machine learning technique, for multi-class mechanical fault diagnosis in bearing of an induction motor. Firstly, the vibration signals are collected from the bearing using accelerometer sensor. Parameters from the vibration signal are extracted in the form of...

  8. Effects of fixed orthodontic treatment and two new mouth rinses on gingival health: A prospective cohort followed by a single-blind placebo-controlled randomized clinical trial.

    Science.gov (United States)

    Sobouti, Farhad; Rakhshan, Vahid; Heydari, Mohaddeseh; Keikavusi, Shohreh; Dadgar, Sepideh; Shariati, Mahsa

    2018-03-01

    Routine brushing protocols might not suffice to reduce the increased plaque accumulation in orthodontic patients. Antimicrobial mouth rinses are favorable in this regard. This two-phase study evaluated the effects of orthodontic treatment and the application of two mouthwashes not studied before on oral health indices. In this two-phase study (a prospective cohort followed by a parallel randomized controlled trial), plaque index (PI), gingival index (GI), gingival bleeding index (GBI), and pocket probing depth (PPD) were measured in 54 orthodontic patients before orthodontic treatment and 4 months later. Then patients were randomized into three groups of mouthrinses: Persica (herbal), Ortho-Kin (containing diluted chlorhexidine), and Placebo (n=18×3). The effects of orthodontic treatment and mouthrinses were analyzed statistically (α=0.05). All the 4 indices increased between the baseline and 4th month of treatment (P values<0.01, paired t-test). They decreased back to baseline levels or below them, after one month of mouthwash application (P values<0.002). Both mouthwashes showed therapeutic effects compared to placebo in terms of PI and GBI. In the case of GI, only Persica showed significantly better results compared to placebo. Regarding PPD, only Ortho-Kin acted better than placebo (P values≤0.05, Tukey). Lack of positive control (regular chlorhexidine mouth rinse) and negative control (a group with no mouthwashes, even without the placebo). Lack of sample size predetermination based on a priori power calculations. The difference between the regime of Persica with that of Ortho-Kin and placebo (which had similar application protocols) disallowed perfectly effective blinding of the patients (hence, single-blind). Fixed orthodontic treatment might disrupt gingival health. Antimicrobial mouthwashes might reverse this. Both evaluated mouthwashes might have therapeutic effects. Copyright © 2018 CEO. Published by Elsevier Masson SAS. All rights reserved.

  9. Comparison of confirmed inactive and randomly selected compounds as negative training examples in support vector machine-based virtual screening.

    Science.gov (United States)

    Heikamp, Kathrin; Bajorath, Jürgen

    2013-07-22

    The choice of negative training data for machine learning is a little explored issue in chemoinformatics. In this study, the influence of alternative sets of negative training data and different background databases on support vector machine (SVM) modeling and virtual screening has been investigated. Target-directed SVM models have been derived on the basis of differently composed training sets containing confirmed inactive molecules or randomly selected database compounds as negative training instances. These models were then applied to search background databases consisting of biological screening data or randomly assembled compounds for available hits. Negative training data were found to systematically influence compound recall in virtual screening. In addition, different background databases had a strong influence on the search results. Our findings also indicated that typical benchmark settings lead to an overestimation of SVM-based virtual screening performance compared to search conditions that are more relevant for practical applications.

  10. Comparison of topical versus intravenous tranexamic acid in primary total knee arthroplasty: a meta-analysis of randomized controlled and prospective cohort trials.

    Science.gov (United States)

    Wang, Hao; Shen, Bin; Zeng, Yi

    2014-12-01

    There has been much debate and controversy about the optimal regimen of tranexamic acid in primary total knee arthroplasty. The purpose of this study was to undertake a meta-analysis to compare the efficacy of topical and intravenous regimen of tranexamic acid in primary total knee arthroplasty. A systematic review of the electronic databases PubMed, CENTRAL, Web of Science, and Embase was undertaken. All randomized controlled trials and prospective cohort studies evaluating the effectiveness of topical and intravenous tranexamic acid during primary total knee arthroplasty were included. The focus of the analysis was on the outcomes of blood loss, transfusion rate, and thromboembolic complications. Subgroup analysis was performed when possible. Of 328 papers identified, six trials were eligible for data extraction and meta-analysis comprising 679 patients (739 knees). We found no statistically significant difference between topical and intravenous administration of tranexamic acid in terms of blood loss, transfusion requirements and thromboembolic complications. Topical tranexamic acid has a similar efficacy to intravenous tranexamic acid in reducing both blood loss and transfusion rate without sacrificing safety in primary total knee arthroplasty. II. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Novel Zn2+-chelating peptides selected from a fimbria-displayed random peptide library

    DEFF Research Database (Denmark)

    Kjærgaard, Kristian; Schembri, Mark; Klemm, Per

    2001-01-01

    The display of peptide sequences on the surface of bacteria is a technology that offers exciting applications in biotechnology and medical research. Type 1 fimbriae are surface organelles of Escherichia coli which mediate D-mannose-sensitive binding to different host surfaces by virtue of the Fim......H adhesin. FimH is a component of the fimbrial organelle that can accommodate and display a diverse range of peptide sequences on the E. coli cell surface. In this study we have constructed a random peptide library in FimH. The library, consisting of similar to 40 million individual clones, was screened...

  12. Retrospective Methods Analysis of Semiautomated Intracerebral Hemorrhage Volume Quantification From a Selection of the STICH II Cohort (Early Surgery Versus Initial Conservative Treatment in Patients With Spontaneous Supratentorial Lobar Intracerebral Haematomas).

    Science.gov (United States)

    Haley, Mark D; Gregson, Barbara A; Mould, W Andrew; Hanley, Daniel F; Mendelow, Alexander David

    2018-02-01

    The ABC/2 method for calculating intracerebral hemorrhage (ICH) volume has been well validated. However, the formula, derived from the volume of an ellipse, assumes the shape of ICH is elliptical. We sought to compare the agreement of the ABC/2 formula with other methods through retrospective analysis of a selection of the STICH II cohort (Early Surgery Versus Initial Conservative Treatment in Patients With Spontaneous Supratentorial Lobar Intracerebral Haematomas). From 390 patients, 739 scans were selected from the STICH II image archive based on the availability of a CT scan compatible with OsiriX DICOM viewer. ICH volumes were calculated by the reference standard semiautomatic segmentation in OsiriX software and compared with calculated arithmetic methods (ABC/2, ABC/2.4, ABC/3, and 2/3SC) volumes. Volumes were compared by difference plots for specific groups: randomization ICH (n=374), 3- to 7-day postsurgical ICH (n=206), antithrombotic-associated ICH (n=79), irregular-shape ICH (n=703) and irregular-density ICH (n=650). Density and shape were measured by the Barras ordinal shape and density groups (1-5). The ABC/2.4 method had the closest agreement to the semiautomatic segmentation volume in all groups, except for the 3- to 7-day postsurgical ICH group where the ABC/3 method was superior. Although the ABC/2 formula for calculating elliptical ICH is well validated, it must be used with caution in ICH scans where the elliptical shape of ICH is a false assumption. We validated the adjustment of the ABC/2.4 method in randomization, antithrombotic-associated, heterogeneous-density, and irregular-shape ICH. URL: http://www.isrctn.com/ISRCTN22153967. Unique identifier: ISRCTN22153967. © 2018 American Heart Association, Inc.

  13. Thyroid Cancer Incidences From Selected South America Population-Based Cancer Registries: An Age-Period-Cohort Study

    Directory of Open Access Journals (Sweden)

    Anne Karin da Mota Borges

    2017-08-01

    Full Text Available Purpose: The incidence of thyroid cancer (TC has increased substantially worldwide. However, there is a lack of knowledge about age-period-cohort (APC effects on incidence rates in South American countries. This study describes the TC incidence trends and analyzes APC effects in Cali, Colombia; Costa Rica; Goiânia, Brazil; and Quito, Ecuador. Materials and Methods: Data were obtained from the Cancer Incidence in Five Continents series, and the crude and age-standardized incidence rates were calculated. Trends were assessed using the estimated annual percentage change, and APC models were estimated using Poisson regression for individuals between age 20 and 79 years. Results: An increasing trend in age-standardized incidence rates was observed among women from Goiânia (9.2%, Costa Rica (5.7%, Quito (4.0%, and Cali (3.4%, and in men from Goiânia (10.0% and Costa Rica (3.4%. The APC modeling showed that there was a period effect in all regions and for both sexes. Increasing rate ratios were observed among women over the periods. The best fit model was the APC model in women from all regions and in men from Quito, whereas the age-cohort model showed a better fit in men from Cali and Costa Rica, and the age-drift model showed a better fit among men from Goiânia. Conclusion: These findings suggest that overdiagnosis is a possible explanation for the observed increasing pattern of TC incidence. However, some environmental exposures may also have contributed to the observed increase.

  14. Predictive Validity of an Empirical Approach for Selecting Promising Message Topics: A Randomized-Controlled Study

    Science.gov (United States)

    Lee, Stella Juhyun; Brennan, Emily; Gibson, Laura Anne; Tan, Andy S. L.; Kybert-Momjian, Ani; Liu, Jiaying; Hornik, Robert

    2016-01-01

    Several message topic selection approaches propose that messages based on beliefs pretested and found to be more strongly associated with intentions will be more effective in changing population intentions and behaviors when used in a campaign. This study aimed to validate the underlying causal assumption of these approaches which rely on cross-sectional belief–intention associations. We experimentally tested whether messages addressing promising themes as identified by the above criterion were more persuasive than messages addressing less promising themes. Contrary to expectations, all messages increased intentions. Interestingly, mediation analyses showed that while messages deemed promising affected intentions through changes in targeted promising beliefs, messages deemed less promising also achieved persuasion by influencing nontargeted promising beliefs. Implications for message topic selection are discussed. PMID:27867218

  15. Oracle Efficient Variable Selection in Random and Fixed Effects Panel Data Models

    DEFF Research Database (Denmark)

    Kock, Anders Bredahl

    This paper generalizes the results for the Bridge estimator of Huang et al. (2008) to linear random and fixed effects panel data models which are allowed to grow in both dimensions. In particular we show that the Bridge estimator is oracle efficient. It can correctly distinguish between relevant...... and irrelevant variables and the asymptotic distribution of the estimators of the coefficients of the relevant variables is the same as if only these had been included in the model, i.e. as if an oracle had revealed the true model prior to estimation. In the case of more explanatory variables than observations......, we prove that the Marginal Bridge estimator can asymptotically correctly distinguish between relevant and irrelevant explanatory variables. We do this without restricting the dependence between covariates and without assuming sub Gaussianity of the error terms thereby generalizing the results...

  16. Presence of psychoactive substances in oral fluid from randomly selected drivers in Denmark

    DEFF Research Database (Denmark)

    Simonsen, K. Wiese; Steentoft, A.; Hels, Tove

    2012-01-01

    . The percentage of drivers positive for medicinal drugs above the Danish legal concentration limit was 0.4%; while, 0.3% of the drivers tested positive for one or more illicit drug at concentrations exceeding the Danish legal limit. Tetrahydrocannabinol, cocaine, and amphetamine were the most frequent illicit......This roadside study is the Danish part of the EU-project DRUID (Driving under the Influence of Drugs, Alcohol, and Medicines) and included three representative regions in Denmark. Oral fluid samples (n = 3002) were collected randomly from drivers using a sampling scheme stratified by time, season......, and road type. The oral fluid samples were screened for 29 illegal and legal psychoactive substances and metabolites as well as ethanol. Fourteen (0.5%) drivers were positive for ethanol alone or in combination with drugs) at concentrations above 0.53 g/l (0.5 mg/g), which is the Danish legal limit...

  17. Correlates of smoking with socioeconomic status, leisure time physical activity and alcohol consumption among Polish adults from randomly selected regions.

    Science.gov (United States)

    Woitas-Slubowska, Donata; Hurnik, Elzbieta; Skarpańska-Stejnborn, Anna

    2010-12-01

    To determine the association between smoking status and leisure time physical activity (LTPA), alcohol consumption, and socioeconomic status (SES) among Polish adults. 466 randomly selected men and women (aged 18-66 years) responded to an anonymous questionnaire regarding smoking, alcohol consumption, LTPA, and SES. Multiple logistic regression was used to examine the association of smoking status with six socioeconomic measures, level of LTPA, and frequency and type of alcohol consumed. Smokers were defined as individuals smoking occasionally or daily. The odds of being smoker were 9 times (men) and 27 times (women) higher among respondents who drink alcohol several times/ week or everyday in comparison to non-drinkers (p times higher compared to those with the high educational attainment (p = 0.007). Among women we observed that students were the most frequent smokers. Female students were almost three times more likely to smoke than non-professional women, and two times more likely than physical workers (p = 0.018). The findings of this study indicated that among randomly selected Polish man and women aged 18-66 smoking and alcohol consumption tended to cluster. These results imply that intervention strategies need to target multiple risk factors simultaneously. The highest risk of smoking was observed among low educated men, female students, and both men and women drinking alcohol several times a week or every day. Information on subgroups with the high risk of smoking will help in planning future preventive strategies.

  18. Genome-wide association data classification and SNPs selection using two-stage quality-based Random Forests.

    Science.gov (United States)

    Nguyen, Thanh-Tung; Huang, Joshua; Wu, Qingyao; Nguyen, Thuy; Li, Mark

    2015-01-01

    Single-nucleotide polymorphisms (SNPs) selection and identification are the most important tasks in Genome-wide association data analysis. The problem is difficult because genome-wide association data is very high dimensional and a large portion of SNPs in the data is irrelevant to the disease. Advanced machine learning methods have been successfully used in Genome-wide association studies (GWAS) for identification of genetic variants that have relatively big effects in some common, complex diseases. Among them, the most successful one is Random Forests (RF). Despite of performing well in terms of prediction accuracy in some data sets with moderate size, RF still suffers from working in GWAS for selecting informative SNPs and building accurate prediction models. In this paper, we propose to use a new two-stage quality-based sampling method in random forests, named ts-RF, for SNP subspace selection for GWAS. The method first applies p-value assessment to find a cut-off point that separates informative and irrelevant SNPs in two groups. The informative SNPs group is further divided into two sub-groups: highly informative and weak informative SNPs. When sampling the SNP subspace for building trees for the forest, only those SNPs from the two sub-groups are taken into account. The feature subspaces always contain highly informative SNPs when used to split a node at a tree. This approach enables one to generate more accurate trees with a lower prediction error, meanwhile possibly avoiding overfitting. It allows one to detect interactions of multiple SNPs with the diseases, and to reduce the dimensionality and the amount of Genome-wide association data needed for learning the RF model. Extensive experiments on two genome-wide SNP data sets (Parkinson case-control data comprised of 408,803 SNPs and Alzheimer case-control data comprised of 380,157 SNPs) and 10 gene data sets have demonstrated that the proposed model significantly reduced prediction errors and outperformed

  19. Infant and Young Child Feeding Practices in Infants Receiving Skin to Skin Care at Birth: Follow-up of Randomized Cohort.

    Science.gov (United States)

    Nimbalkar, Archana Somashekhar; Patel, Dipen Vasudev; Nimbalkar, Somashekhar Marutirao; Patel, Vijay Karshanbhai; Patel, Dhaval Nileshbhai; Phatak, Ajay Gajanan

    2016-12-01

    Skin to Skin Care (SSC) in neonatal period influences immediate breastfeeding outcomes in early childhood, especially the duration of exclusive breastfeeding. We investigated influence of 17 hours of SSC given from day one of life on Infant and Young Child Feeding (IYCF) practices through one year of life. Follow-up of a Superiority Randomized Control Trial (RCT) (CTRI/2013/06/003790) conducted in a teaching hospital located in central Gujarat. Mothers of 100 neonates (48 girls, 52 boys) from previous study cohort of RCT on SSC were followed. A survey on IYCF practices during the first year of life was administered after the end of infancy. In RCT, 50 neonates had received SSC beginning of 30 min- 1 hour after birth for average 17 hours on day 1 of life. In the control group, 50 newborn were placed next to the mother and conventional care was provided. There was a significant difference between hypothermia incidences in these groups in the first two days of life. There was no difference in the groups as far as the duration of exclusive breastfeeding, number of times breastfed per day, or stoppage of night feeds. No baby in either group received bottled feeds but about 53 received some form of extra lacteal feeds in the first 6 months without significant group difference. Fewer SSC mothers reported difficulties with breastfeeding or extra lacteal supplementation. All mothers who faced problems contacted physicians for advice and 20 were advised top milk and 6 given other foods. At one year of life 66% mothers were giving less than the recommended five food servings. There was no difference in practices related to hand washing, food preparation and storage, feeding habits of child and illness episodes in the children. IYCF practices in this small group were not as per guidelines. Few positive trends were seen with fewer SSC mothers facing problems related to breastfeeding. The study was underpowered to detect differences in IYCF practices in relation to SSC.

  20. Two-stage revision surgery with preformed spacers and cementless implants for septic hip arthritis: a prospective, non-randomized cohort study

    Directory of Open Access Journals (Sweden)

    Logoluso Nicola

    2011-05-01

    Full Text Available Abstract Background Outcome data on two-stage revision surgery for deep infection after septic hip arthritis are limited and inconsistent. This study presents the medium-term results of a new, standardized two-stage arthroplasty with preformed hip spacers and cementless implants in a consecutive series of adult patients with septic arthritis of the hip treated according to a same protocol. Methods Nineteen patients (20 hips were enrolled in this prospective, non-randomized cohort study between 2000 and 2008. The first stage comprised femoral head resection, debridement, and insertion of a preformed, commercially available, antibiotic-loaded cement hip spacer. After eradication of infection, a cementless total hip arthroplasty was implanted in the second stage. Patients were assessed for infection recurrence, pain (visual analog scale [VAS] and hip joint function (Harris Hip score. Results The mean time between first diagnosis of infection and revision surgery was 5.8 ± 9.0 months; the average duration of follow up was 56.6 (range, 24 - 104 months; all 20 hips were successfully converted to prosthesis an average 22 ± 5.1 weeks after spacer implantation. Reinfection after total hip joint replacement occurred in 1 patient. The mean VAS pain score improved from 48 (range, 35 - 84 pre-operatively to 18 (range, 0 - 38 prior to spacer removal and to 8 (range, 0 - 15 at the last follow-up assessment after prosthesis implantation. The average Harris Hip score improved from 27.5 before surgery to 61.8 between the two stages to 92.3 at the final follow-up assessment. Conclusions Satisfactory outcomes can be obtained with two-stage revision hip arthroplasty using preformed spacers and cementless implants for prosthetic hip joint infections of various etiologies.

  1. Capturing the Flatness of a peer-to-peer lending network through random and selected perturbations

    Science.gov (United States)

    Karampourniotis, Panagiotis D.; Singh, Pramesh; Uparna, Jayaram; Horvat, Emoke-Agnes; Szymanski, Boleslaw K.; Korniss, Gyorgy; Bakdash, Jonathan Z.; Uzzi, Brian

    Null models are established tools that have been used in network analysis to uncover various structural patterns. They quantify the deviance of an observed network measure to that given by the null model. We construct a null model for weighted, directed networks to identify biased links (carrying significantly different weights than expected according to the null model) and thus quantify the flatness of the system. Using this model, we study the flatness of Kiva, a large international crownfinancing network of borrowers and lenders, aggregated to the country level. The dataset spans the years from 2006 to 2013. Our longitudinal analysis shows that flatness of the system is reducing over time, meaning the proportion of biased inter-country links is growing. We extend our analysis by testing the robustness of the flatness of the network in perturbations on the links' weights or the nodes themselves. Examples of such perturbations are event shocks (e.g. erecting walls) or regulatory shocks (e.g. Brexit). We find that flatness is unaffected by random shocks, but changes after shocks target links with a large weight or bias. The methods we use to capture the flatness are based on analytics, simulations, and numerical computations using Shannon's maximum entropy. Supported by ARL NS-CTA.

  2. Participant-selected music and physical activity in older adults following cardiac rehabilitation: a randomized controlled trial.

    Science.gov (United States)

    Clark, Imogen N; Baker, Felicity A; Peiris, Casey L; Shoebridge, Georgie; Taylor, Nicholas F

    2017-03-01

    To evaluate effects of participant-selected music on older adults' achievement of activity levels recommended in the physical activity guidelines following cardiac rehabilitation. A parallel group randomized controlled trial with measurements at Weeks 0, 6 and 26. A multisite outpatient rehabilitation programme of a publicly funded metropolitan health service. Adults aged 60 years and older who had completed a cardiac rehabilitation programme. Experimental participants selected music to support walking with guidance from a music therapist. Control participants received usual care only. The primary outcome was the proportion of participants achieving activity levels recommended in physical activity guidelines. Secondary outcomes compared amounts of physical activity, exercise capacity, cardiac risk factors, and exercise self-efficacy. A total of 56 participants, mean age 68.2 years (SD = 6.5), were randomized to the experimental ( n = 28) and control groups ( n = 28). There were no differences between groups in proportions of participants achieving activity recommended in physical activity guidelines at Week 6 or 26. Secondary outcomes demonstrated between-group differences in male waist circumference at both measurements (Week 6 difference -2.0 cm, 95% CI -4.0 to 0; Week 26 difference -2.8 cm, 95% CI -5.4 to -0.1), and observed effect sizes favoured the experimental group for amounts of physical activity (d = 0.30), exercise capacity (d = 0.48), and blood pressure (d = -0.32). Participant-selected music did not increase the proportion of participants achieving recommended amounts of physical activity, but may have contributed to exercise-related benefits.

  3. Mirnacle: machine learning with SMOTE and random forest for improving selectivity in pre-miRNA ab initio prediction.

    Science.gov (United States)

    Marques, Yuri Bento; de Paiva Oliveira, Alcione; Ribeiro Vasconcelos, Ana Tereza; Cerqueira, Fabio Ribeiro

    2016-12-15

    MicroRNAs (miRNAs) are key gene expression regulators in plants and animals. Therefore, miRNAs are involved in several biological processes, making the study of these molecules one of the most relevant topics of molecular biology nowadays. However, characterizing miRNAs in vivo is still a complex task. As a consequence, in silico methods have been developed to predict miRNA loci. A common ab initio strategy to find miRNAs in genomic data is to search for sequences that can fold into the typical hairpin structure of miRNA precursors (pre-miRNAs). The current ab initio approaches, however, have selectivity issues, i.e., a high number of false positives is reported, which can lead to laborious and costly attempts to provide biological validation. This study presents an extension of the ab initio method miRNAFold, with the aim of improving selectivity through machine learning techniques, namely, random forest combined with the SMOTE procedure that copes with imbalance datasets. By comparing our method, termed Mirnacle, with other important approaches in the literature, we demonstrate that Mirnacle substantially improves selectivity without compromising sensitivity. For the three datasets used in our experiments, our method achieved at least 97% of sensitivity and could deliver a two-fold, 20-fold, and 6-fold increase in selectivity, respectively, compared with the best results of current computational tools. The extension of miRNAFold by the introduction of machine learning techniques, significantly increases selectivity in pre-miRNA ab initio prediction, which optimally contributes to advanced studies on miRNAs, as the need of biological validations is diminished. Hopefully, new research, such as studies of severe diseases caused by miRNA malfunction, will benefit from the proposed computational tool.

  4. Reduced plasma aldosterone concentrations in randomly selected patients with insulin-dependent diabetes mellitus.

    LENUS (Irish Health Repository)

    Cronin, C C

    2012-02-03

    Abnormalities of the renin-angiotensin system have been reported in patients with diabetes mellitus and with diabetic complications. In this study, plasma concentrations of prorenin, renin, and aldosterone were measured in a stratified random sample of 110 insulin-dependent (Type 1) diabetic patients attending our outpatient clinic. Fifty-four age- and sex-matched control subjects were also examined. Plasma prorenin concentration was higher in patients without complications than in control subjects when upright (geometric mean (95% confidence intervals (CI): 75.9 (55.0-105.6) vs 45.1 (31.6-64.3) mU I-1, p < 0.05). There was no difference in plasma prorenin concentration between patients without and with microalbuminuria and between patients without and with background retinopathy. Plasma renin concentration, both when supine and upright, was similar in control subjects, in patients without complications, and in patients with varying degrees of diabetic microangiopathy. Plasma aldosterone was suppressed in patients without complications in comparison to control subjects (74 (58-95) vs 167 (140-199) ng I-1, p < 0.001) and was also suppressed in patients with microvascular disease. Plasma potassium was significantly higher in patients than in control subjects (mean +\\/- standard deviation: 4.10 +\\/- 0.36 vs 3.89 +\\/- 0.26 mmol I-1; p < 0.001) and plasma sodium was significantly lower (138 +\\/- 4 vs 140 +\\/- 2 mmol I-1; p < 0.001). We conclude that plasma prorenin is not a useful early marker for diabetic microvascular disease. Despite apparently normal plasma renin concentrations, plasma aldosterone is suppressed in insulin-dependent diabetic patients.

  5. A Permutation Importance-Based Feature Selection Method for Short-Term Electricity Load Forecasting Using Random Forest

    Directory of Open Access Journals (Sweden)

    Nantian Huang

    2016-09-01

    Full Text Available The prediction accuracy of short-term load forecast (STLF depends on prediction model choice and feature selection result. In this paper, a novel random forest (RF-based feature selection method for STLF is proposed. First, 243 related features were extracted from historical load data and the time information of prediction points to form the original feature set. Subsequently, the original feature set was used to train an RF as the original model. After the training process, the prediction error of the original model on the test set was recorded and the permutation importance (PI value of each feature was obtained. Then, an improved sequential backward search method was used to select the optimal forecasting feature subset based on the PI value of each feature. Finally, the optimal forecasting feature subset was used to train a new RF model as the final prediction model. Experiments showed that the prediction accuracy of RF trained by the optimal forecasting feature subset was higher than that of the original model and comparative models based on support vector regression and artificial neural network.

  6. Classifying Pediatric Central Nervous System Tumors through near Optimal Feature Selection and Mutual Information: A Single Center Cohort

    Directory of Open Access Journals (Sweden)

    Mohammad Faranoush

    2013-10-01

    Full Text Available Background: Labeling, gathering mutual information, clustering and classificationof central nervous system tumors may assist in predicting not only distinct diagnosesbased on tumor-specific features but also prognosis. This study evaluates the epidemi-ological features of central nervous system tumors in children who referred to Mahak’sPediatric Cancer Treatment and Research Center in Tehran, Iran.Methods: This cohort (convenience sample study comprised 198 children (≤15years old with central nervous system tumors who referred to Mahak's PediatricCancer Treatment and Research Center from 2007 to 2010. In addition to the descriptiveanalyses on epidemiological features and mutual information, we used the LeastSquares Support Vector Machines method in MATLAB software to propose apreliminary predictive model of pediatric central nervous system tumor feature-labelanalysis. Results:Of patients, there were 63.1% males and 36.9% females. Patients' mean±SDage was 6.11±3.65 years. Tumor location was as follows: supra-tentorial (30.3%, infra-tentorial (67.7% and 2% (spinal. The most frequent tumors registered were: high-gradeglioma (supra-tentorial in 36 (59.99% patients and medulloblastoma (infra-tentorialin 65 (48.51% patients. The most prevalent clinical findings included vomiting,headache and impaired vision. Gender, age, ethnicity, tumor stage and the presence ofmetastasis were the features predictive of supra-tentorial tumor histology.Conclusion: Our data agreed with previous reports on the epidemiology of centralnervous system tumors. Our feature-label analysis has shown how presenting features maypartially predict diagnosis. Timely diagnosis and management of central nervous systemtumors can lead to decreased disease burden and improved survival. This may be furtherfacilitated through development of partitioning, risk prediction and prognostic models.

  7. SAT0125 The impact of selected comorbidities on treatment outcome in patients with rheumatoid arthritis: an exploratory cohort study

    DEFF Research Database (Denmark)

    Emamifar, Amir; Jensen Hansen, Inger Marie

    2018-01-01

    diagnosed rheumatoid arthritis is associated with poor initial treatment response evaluated by disease activity score in 28 joints-C-reactive protein (DAS28- CRP): An observational cohort study. Medicine (Baltimore) 2017;96:e8357. [2] Emamifar A, et al. Patients with newly diagnosed Rheumatoid Arthritis......Background: Patients with Rheumatoid Arthritis (RA) may present with various comorbidities resulting in worse treatment response.[1-2] Objectives: To investigate the impact of selected comorbid diseases on RA outcome with the aim of Disease Activity Score in 28 joints-C-Reactive Protein (DAS28-CRP......). Methods: All our RA patients were included in this study. Patients’ demographics, serology results and DAS28-CRP at the time of diagnosis and after 4 months of treatment initiation were collected. Patients’ electronic hospital records were evaluated for a positive history of thyroid diseases, Diabetes...

  8. Nitrates and bone turnover (NABT) - trial to select the best nitrate preparation: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Bucur, Roxana C; Reid, Lauren S; Hamilton, Celeste J; Cummings, Steven R; Jamal, Sophie A

    2013-09-08

    comparisons with the best' approach for data analyses, as this strategy allows practical considerations of ease of use and tolerability to guide selection of the preparation for future studies. Data from this protocol will be used to develop a randomized, controlled trial of nitrates to prevent osteoporotic fractures. ClinicalTrials.gov Identifier: NCT01387672. Controlled-Trials.com: ISRCTN08860742.

  9. Non-Random Inversion Landscapes in Prokaryotic Genomes Are Shaped by Heterogeneous Selection Pressures.

    Science.gov (United States)

    Repar, Jelena; Warnecke, Tobias

    2017-08-01

    Inversions are a major contributor to structural genome evolution in prokaryotes. Here, using a novel alignment-based method, we systematically compare 1,651 bacterial and 98 archaeal genomes to show that inversion landscapes are frequently biased toward (symmetric) inversions around the origin-terminus axis. However, symmetric inversion bias is not a universal feature of prokaryotic genome evolution but varies considerably across clades. At the extremes, inversion landscapes in Bacillus-Clostridium and Actinobacteria are dominated by symmetric inversions, while there is little or no systematic bias favoring symmetric rearrangements in archaea with a single origin of replication. Within clades, we find strong but clade-specific relationships between symmetric inversion bias and different features of adaptive genome architecture, including the distance of essential genes to the origin of replication and the preferential localization of genes on the leading strand. We suggest that heterogeneous selection pressures have converged to produce similar patterns of structural genome evolution across prokaryotes. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  10. Quality of life after antegrade intramedullary nail fixation of humeral fractures: a survey in a selected cohort of Brazilian patients.

    Science.gov (United States)

    Cocco, Luiz Fernando; Ejnisman, Benno; Belangero, Paulo Santoro; Cohen, Moises; Dos Reis, Fernando Baldy

    2018-01-01

    The treatment of humeral fractures remains controversial. Systematic reviews demonstrate similar results between dynamic compression plating and locked intramedullary nailing in the surgical treatment of these fractures. However, it appears that antegrade intramedullary nailing causes higher residual pain in the shoulder. The proposal of this work is to evaluate through the WORC protocol (Western Ontario Rotator Cuff Index) the consequences in the quality of life of patients submitted to osteosynthesis of the humerus with antegrade locked intramedullary nailing. This work is a cohort retrospective study in addition to the application of a questionnaire for self-rated quality of life with its 05 domains (WORC - Western Ontario Rotator Cuff Index) for patients ( N  = 26) classified in the Trauma Sector of the Department of Orthopedics and Traumatology of the Federal University of São Paulo (DOT/UNIFESP) submitted to Humerus Osteosynthesis with Antegrade Locked Intramedullary Nailing. There was also the inclusion of data related to the time since surgery, age, sex, surgical laterality, dominance among members and work leave, which were not considered in the original protocol. After, the data were statistically assessed to evaluate the association between numerical and categorical variables. The overall WORC score was 82.75 ± 17.00 (Mean ± SD) and was not different considering sex, age and postoperative period. Among the WORC domains, both Work and Sport / Recreation Protocols were the most unfavorable factors in the evaluation of patients. Although not statistically significant, those who had the procedure on the dominant side presented a lower quality of life score than those who had the surgery on the non-dominant side. Although non-significant again, those who were away from work had an overall lower quality of life score than those who were not. The WORC Quality of Life Protocol shows good results for evaluating patients submitted to humerus

  11. Fast selection of miRNA candidates based on large-scale pre-computed MFE sets of randomized sequences.

    Science.gov (United States)

    Warris, Sven; Boymans, Sander; Muiser, Iwe; Noback, Michiel; Krijnen, Wim; Nap, Jan-Peter

    2014-01-13

    Small RNAs are important regulators of genome function, yet their prediction in genomes is still a major computational challenge. Statistical analyses of pre-miRNA sequences indicated that their 2D structure tends to have a minimal free energy (MFE) significantly lower than MFE values of equivalently randomized sequences with the same nucleotide composition, in contrast to other classes of non-coding RNA. The computation of many MFEs is, however, too intensive to allow for genome-wide screenings. Using a local grid infrastructure, MFE distributions of random sequences were pre-calculated on a large scale. These distributions follow a normal distribution and can be used to determine the MFE distribution for any given sequence composition by interpolation. It allows on-the-fly calculation of the normal distribution for any candidate sequence composition. The speedup achieved makes genome-wide screening with this characteristic of a pre-miRNA sequence practical. Although this particular property alone will not be able to distinguish miRNAs from other sequences sufficiently discriminative, the MFE-based P-value should be added to the parameters of choice to be included in the selection of potential miRNA candidates for experimental verification.

  12. Selecting Optimal Random Forest Predictive Models: A Case Study on Predicting the Spatial Distribution of Seabed Hardness

    Science.gov (United States)

    Li, Jin; Tran, Maggie; Siwabessy, Justy

    2016-01-01

    Spatially continuous predictions of seabed hardness are important baseline environmental information for sustainable management of Australia’s marine jurisdiction. Seabed hardness is often inferred from multibeam backscatter data with unknown accuracy and can be inferred from underwater video footage at limited locations. In this study, we classified the seabed into four classes based on two new seabed hardness classification schemes (i.e., hard90 and hard70). We developed optimal predictive models to predict seabed hardness using random forest (RF) based on the point data of hardness classes and spatially continuous multibeam data. Five feature selection (FS) methods that are variable importance (VI), averaged variable importance (AVI), knowledge informed AVI (KIAVI), Boruta and regularized RF (RRF) were tested based on predictive accuracy. Effects of highly correlated, important and unimportant predictors on the accuracy of RF predictive models were examined. Finally, spatial predictions generated using the most accurate models were visually examined and analysed. This study confirmed that: 1) hard90 and hard70 are effective seabed hardness classification schemes; 2) seabed hardness of four classes can be predicted with a high degree of accuracy; 3) the typical approach used to pre-select predictive variables by excluding highly correlated variables needs to be re-examined; 4) the identification of the important and unimportant predictors provides useful guidelines for further improving predictive models; 5) FS methods select the most accurate predictive model(s) instead of the most parsimonious ones, and AVI and Boruta are recommended for future studies; and 6) RF is an effective modelling method with high predictive accuracy for multi-level categorical data and can be applied to ‘small p and large n’ problems in environmental sciences. Additionally, automated computational programs for AVI need to be developed to increase its computational efficiency and

  13. A psycho-educational HIV/STI prevention intervention for internally displaced women in Leogane, Haiti: results from a non-randomized cohort pilot study.

    Science.gov (United States)

    Logie, Carmen H; Daniel, CarolAnn; Newman, Peter A; Weaver, James; Loutfy, Mona R

    2014-01-01

    Little evidence exists regarding efficacious HIV and sexually transmitted infections (STI) prevention interventions with internally displaced populations. Internally displaced women are at elevated risk for HIV/STI due to limited access to health services, heightened poverty and social network breakdown. The FASY (Famn an Aksyon Pou Sante' Yo) (Women Taking Action For Their Health) study examined the effectiveness of a peer health worker (PHW) delivered psycho-educational HIV/STI pilot study with internally displaced women in Leogane, Haiti. This was a non-randomized cohort pilot study. Participants completed a computer-assisted pre-test programmed on Android tablet PCs followed by an HIV/STI educational video-based session and a 6-week psycho-educational group program of weekly meetings. Participants completed a post-test upon completion of group sessions. The primary outcome was HIV knowledge; our pre-specified index of clinically significant change was an effect size of 0.30. Secondary outcomes included: STI knowledge, condom use, social support, resilient coping, depression and relationship control. We used mixed-effects regression to calculate mean outcome pre-post score change. This study was registered (clinicaltrials.gov, NCT01492829). Between January 1-April 30, 2012 we assigned 200 participants to the study. The majority of participants (n = 176, 88%) completed the study and were followed up at 8 weeks, finishing April 30, 2012. Adjusted for socio-demographic characteristics, HIV knowledge (β = 4.81; 95% CI 4.36-5.26), STI knowledge (β = 0.84; 95% CI 0.70-0.99), condom use (AOR = 4.05, 95% CI 1.86-8.83), and depression (β = -0.63, 95% CI -0.88--0.39) scores showed statistically significant change post-intervention (pHaiti. Pilot studies are an important approach to understand feasibility and scientific impacts of HIV prevention strategies in disaster contexts. Study results may inform HIV prevention interventions among internally displaced women in

  14. A psycho-educational HIV/STI prevention intervention for internally displaced women in Leogane, Haiti: results from a non-randomized cohort pilot study.

    Directory of Open Access Journals (Sweden)

    Carmen H Logie

    Full Text Available Little evidence exists regarding efficacious HIV and sexually transmitted infections (STI prevention interventions with internally displaced populations. Internally displaced women are at elevated risk for HIV/STI due to limited access to health services, heightened poverty and social network breakdown. The FASY (Famn an Aksyon Pou Sante' Yo (Women Taking Action For Their Health study examined the effectiveness of a peer health worker (PHW delivered psycho-educational HIV/STI pilot study with internally displaced women in Leogane, Haiti.This was a non-randomized cohort pilot study. Participants completed a computer-assisted pre-test programmed on Android tablet PCs followed by an HIV/STI educational video-based session and a 6-week psycho-educational group program of weekly meetings. Participants completed a post-test upon completion of group sessions. The primary outcome was HIV knowledge; our pre-specified index of clinically significant change was an effect size of 0.30. Secondary outcomes included: STI knowledge, condom use, social support, resilient coping, depression and relationship control. We used mixed-effects regression to calculate mean outcome pre-post score change. This study was registered (clinicaltrials.gov, NCT01492829.Between January 1-April 30, 2012 we assigned 200 participants to the study. The majority of participants (n = 176, 88% completed the study and were followed up at 8 weeks, finishing April 30, 2012. Adjusted for socio-demographic characteristics, HIV knowledge (β = 4.81; 95% CI 4.36-5.26, STI knowledge (β = 0.84; 95% CI 0.70-0.99, condom use (AOR = 4.05, 95% CI 1.86-8.83, and depression (β = -0.63, 95% CI -0.88--0.39 scores showed statistically significant change post-intervention (p<0.05.This pilot study evaluated a PHW psycho-educational HIV/STI prevention intervention among internally displaced women in post-earthquake Haiti. Pilot studies are an important approach to understand feasibility and scientific

  15. Performance of Universal Adhesive in Primary Molars After Selective Removal of Carious Tissue: An 18-Month Randomized Clinical Trial.

    Science.gov (United States)

    Lenzi, Tathiane Larissa; Pires, Carine Weber; Soares, Fabio Zovico Maxnuck; Raggio, Daniela Prócida; Ardenghi, Thiago Machado; de Oliveira Rocha, Rachel

    2017-09-15

    To evaluate the 18-month clinical performance of a universal adhesive, applied under different adhesion strategies, after selective carious tissue removal in primary molars. Forty-four subjects (five to 10 years old) contributed with 90 primary molars presenting moderately deep dentin carious lesions on occlusal or occluso-proximal surfaces, which were randomly assigned following either self-etch or etch-and-rinse protocol of Scotchbond Universal Adhesive (3M ESPE). Resin composite was incrementally inserted for all restorations. Restorations were evaluated at one, six, 12, and 18 months using the modified United States Public Health Service criteria. Survival estimates for restorations' longevity were evaluated using the Kaplan-Meier method. Multivariate Cox regression analysis with shared frailty to assess the factors associated with failures (Padhesion strategy did not influence the restorations' longevity (P=0.06; 72.2 percent and 89.7 percent with etch-and-rinse and self-etch mode, respectively). Self-etch and etch-and-rinse strategies did not influence the clinical behavior of universal adhesive used in primary molars after selective carious tissue removal; although there was a tendency for better outcome of the self-etch strategy.

  16. DNABP: Identification of DNA-Binding Proteins Based on Feature Selection Using a Random Forest and Predicting Binding Residues.

    Science.gov (United States)

    Ma, Xin; Guo, Jing; Sun, Xiao

    2016-01-01

    DNA-binding proteins are fundamentally important in cellular processes. Several computational-based methods have been developed to improve the prediction of DNA-binding proteins in previous years. However, insufficient work has been done on the prediction of DNA-binding proteins from protein sequence information. In this paper, a novel predictor, DNABP (DNA-binding proteins), was designed to predict DNA-binding proteins using the random forest (RF) classifier with a hybrid feature. The hybrid feature contains two types of novel sequence features, which reflect information about the conservation of physicochemical properties of the amino acids, and the binding propensity of DNA-binding residues and non-binding propensities of non-binding residues. The comparisons with each feature demonstrated that these two novel features contributed most to the improvement in predictive ability. Furthermore, to improve the prediction performance of the DNABP model, feature selection using the minimum redundancy maximum relevance (mRMR) method combined with incremental feature selection (IFS) was carried out during the model construction. The results showed that the DNABP model could achieve 86.90% accuracy, 83.76% sensitivity, 90.03% specificity and a Matthews correlation coefficient of 0.727. High prediction accuracy and performance comparisons with previous research suggested that DNABP could be a useful approach to identify DNA-binding proteins from sequence information. The DNABP web server system is freely available at http://www.cbi.seu.edu.cn/DNABP/.

  17. Selective Intermittent Preventive Treatment of Vivax Malaria: Reduction of Malaria Incidence in an Open Cohort Study in Brazilian Amazon

    Science.gov (United States)

    Gil, Luiz Herman Soares; de Lima, Alzemar Alves; Freitag, Elci Marlei; dos Santos, Tatiana Marcondes; do Nascimento Filha, Maria Teixeira; dos Santos Júnior, Alcides Procópio Justiniano; da Silva, Josiane Mendes; Rodrigues, Aline de Freitas; Tada, Mauro Shugiro; Fontes, Cor Jesus Fernandes; Pereira da Silva, Luiz Hildebrando

    2013-01-01

    In children, the Intermittent Preventive Treatment (IPTc), currently called Seasonal Malaria Chemoprevention (SMC), was considered effective on malaria control due to the reduction of its incidence in Papua New Guinea and in some areas with seasonal malaria in Africa. However, the IPT has not been indicated because of its association with drug resistance and for hindering natural immunity development. Thus, we evaluated the alternative IPT impact on malaria incidence in three riverside communities on Madeira River, in the municipality of Porto Velho, RO. We denominate this scheme Selective Intermittent Preventive Treatment (SIPT). The SIPT consists in a weekly dose of two 150 mg chloroquine tablets for 12 weeks, for adults, and an equivalent dose for children, after complete supervised treatment for P. vivax infection. This scheme is recommend by Brazilian Health Ministry to avoid frequent relapses. The clinic parasitological and epidemiological surveillance showed a significant reduction on vivax malaria incidence. The results showed a reduction on relapses and recurrence of malaria after SIPT implementation. The SIPT can be effective on vivax malaria control in localities with high transmission risk in the Brazilian Amazon. PMID:23577276

  18. Selective Intermittent Preventive Treatment of Vivax Malaria: Reduction of Malaria Incidence in an Open Cohort Study in Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Tony Hiroshi Katsuragawa

    2013-01-01

    Full Text Available In children, the Intermittent Preventive Treatment (IPTc, currently called Seasonal Malaria Chemoprevention (SMC, was considered effective on malaria control due to the reduction of its incidence in Papua New Guinea and in some areas with seasonal malaria in Africa. However, the IPT has not been indicated because of its association with drug resistance and for hindering natural immunity development. Thus, we evaluated the alternative IPT impact on malaria incidence in three riverside communities on Madeira River, in the municipality of Porto Velho, RO. We denominate this scheme Selective Intermittent Preventive Treatment (SIPT. The SIPT consists in a weekly dose of two 150 mg chloroquine tablets for 12 weeks, for adults, and an equivalent dose for children, after complete supervised treatment for P. vivax infection. This scheme is recommend by Brazilian Health Ministry to avoid frequent relapses. The clinic parasitological and epidemiological surveillance showed a significant reduction on vivax malaria incidence. The results showed a reduction on relapses and recurrence of malaria after SIPT implementation. The SIPT can be effective on vivax malaria control in localities with high transmission risk in the Brazilian Amazon.

  19. Risk of preeclampsia after gestational exposure to selective serotonin reuptake inhibitors and other antidepressants: A study from The Norwegian Mother and Child Cohort Study.

    Science.gov (United States)

    Lupattelli, Angela; Wood, Mollie; Lapane, Kate; Spigset, Olav; Nordeng, Hedvig

    2017-10-01

    To describe the risk of early- and late-onset preeclampsia across pregnancies exposed to antidepressants and to evaluate the impact of timing and length of gestational exposure to antidepressants, particularly selective serotonin reuptake inhibitors (SSRIs), on preeclampsia. The Norwegian Mother and Child Cohort, a prospective population-based study, and the Medical Birth Registry of Norway provided information on antidepressant exposure, depression, and anxiety symptoms in pregnancy, preeclampsia diagnoses, and important covariates. Within a pregnancy cohort of depressed women, we compared the risk of late-onset preeclampsia between SSRI-exposed and nonmedicated pregnancies using marginal structural models (weighted) and modified Poisson regression models. Of the 5887 pregnancies included, 11.1% were exposed at any time before week 34 to SSRIs, 1.3% to serotonin-norepinephrine reuptake inhibitors, 0.4% to tricyclic antidepressants, and 0.5% to other antidepressants. The risks of early- and late-onset preeclampsia by exposure status in pregnancy were 0.3% and 3.6% (nonmedicated), 0.4% and 3.7% (SSRIs), 1.5% and 4.1% (serotonin-norepinephrine reuptake inhibitors), and 7.1% and 10.0% (tricyclic antidepressants). Compared with nonmedicated pregnancies, SSRI-exposed in mid and late gestation had adjusted relative risks for late-onset mild preeclampsia of 0.76 (95% confidence interval, 0.38-1.53) and 1.56 (0.71-3.44) (weighted models), respectively. There was no association between SSRI exposure in pregnancy and severe late-onset preeclampsia. We have provided evidence that SSRI use in early and midpregnancy does not substantially increase the risk of late-onset preeclampsia. © 2017 The Authors. Pharmacoepidemiology & Drug Safety published by John Wiley & Sons Ltd.

  20. Habitat selection and quality for multiple cohorts of young-of-the-year bluefish ( Pomatomus saltatrix): Comparisons between estuarine and ocean beaches in southern New Jersey

    Science.gov (United States)

    Taylor, David L.; Nichols, Ryan S.; Able, Kenneth W.

    2007-07-01

    In this study, seasonal and annual variability in the use of estuarine and ocean beaches by young-of-the-year bluefish, Pomatomus saltatrix, was evaluated by indices of abundance in coastal areas of southern New Jersey (1998-2000). Biological and physical factors measured at specific sites were correlated with bluefish abundance to determine the mechanisms underlying habitat selection. In addition, integrative and discrete indicators of bluefish growth were used to examine spatio-temporal dynamics in habitat quality and its effect on habitat selection by multiple cohorts of bluefish. Intra-annual recruitment to coastal areas of southern New Jersey was episodic, and resulted from the ingress of spring-spawned bluefish (hatch-date ˜April) to estuarine beaches in late May to early June, followed by the recruitment of summer-spawned fish (hatch-date ˜early July) to ocean beaches from July to October. Bluefish utilized estuarine and ocean beaches in a facultative manner that was responsive to dynamics in prey composition and temperature conditions. The recruitment and residency of bluefish in the estuary (1998-1999) and ocean beaches (1998), for example, was coincidental with the presence of the Atlantic silverside Menidia menidia and bay anchovy Anchoa mitchilli, the principal prey species for bluefish occupying these respective habitat-types. Bluefish abundance in the estuary (2000) and ocean beaches (1999-2000) was also correlated with water temperature, with the greatest catches of juveniles coinciding with their optimal growth temperature (24 °C). Bluefish growth, estimated as the slope of age-length relationships and daily specific growth rates, equaled 1.27-2.63 mm fork length (FL) d -1 and 3.8-8.7% body length increase d -1, respectively. The growth of sagittal otoliths was also used as a proxy for changes in bluefish size during and shortly before their time of capture. Accordingly, otolith growth rates of summer-spawned bluefish were greater at ocean

  1. Cohort Coefficients

    DEFF Research Database (Denmark)

    Kristensen, Gustav

    2013-01-01

    Cohorts are the aggregate of individuals who experience the same event within the same time interval. Cohorts can be based on people born in a given year, for example in 1940 or within a span of years, e.g. born in 1940-1944. The year of birth is here the defining event for cohorts. The health di...... differs between cohorts. This article focuses on the protective and detrimental cohort effect in relation to the risk of death from apoplexy. A dummy variable method is recommended to describe the changing cohort effect over a century....

  2. Secondary Analysis under Cohort Sampling Designs Using Conditional Likelihood

    Directory of Open Access Journals (Sweden)

    Olli Saarela

    2012-01-01

    Full Text Available Under cohort sampling designs, additional covariate data are collected on cases of a specific type and a randomly selected subset of noncases, primarily for the purpose of studying associations with a time-to-event response of interest. With such data available, an interest may arise to reuse them for studying associations between the additional covariate data and a secondary non-time-to-event response variable, usually collected for the whole study cohort at the outset of the study. Following earlier literature, we refer to such a situation as secondary analysis. We outline a general conditional likelihood approach for secondary analysis under cohort sampling designs and discuss the specific situations of case-cohort and nested case-control designs. We also review alternative methods based on full likelihood and inverse probability weighting. We compare the alternative methods for secondary analysis in two simulated settings and apply them in a real-data example.

  3. A randomized control trial to establish the feasibility and safety of rapamycin treatment in an older human cohort: Immunological, physical performance, and cognitive effects.

    Science.gov (United States)

    Kraig, Ellen; Linehan, Leslie A; Liang, Hanyu; Romo, Terry Q; Liu, Qianqian; Wu, Yubo; Benavides, Adriana D; Curiel, Tyler J; Javors, Martin A; Musi, Nicolas; Chiodo, Laura; Koek, Wouter; Gelfond, Jonathan A L; Kellogg, Dean L

    2018-05-01

    Inhibition of the mechanistic target of rapamycin (mTOR) pathway by rapamycin (RAPA), an FDA-approved immunosuppressive drug used as a clinical therapy to prevent solid organ allograft rejection, enhances longevity in mice. Importantly, RAPA was efficacious even when initiated in relatively old animals, suggesting that mTOR inhibition could potentially slow the progression of aging-associated pathologies in older humans (Harrison et al., 2009; Miller et al., 2011). However, the safety and tolerability of RAPA in older human subjects have not yet been demonstrated. Towards this end, we undertook a placebo-controlled pilot study in 25 generally healthy older adults (aged 70-95 years); subjects were randomized to receive either 1 mg RAPA or placebo daily. Although three subjects withdrew, 11 RAPA and 14 controls completed at least 8 weeks of treatment and were included in the analysis. We monitored for changes that would indicate detrimental effects of RAPA treatment on metabolism, including both standard clinical laboratory assays (CBC, CMP, HbA1c) and oral glucose tolerance tests (OGTTs). We also monitored parameters typically associated with aging that could potentially be modified by RAPA; these included cognitive function which was assessed by three different tools: Executive Interview-25 (EXIT25); Saint Louis University Mental Status Exam (SLUMS); and Texas Assessment of Processing Speed (TAPS). In addition, physical performance was measured by handgrip strength and 40-foot timed walks. Lastly, changes in general parameters of healthy immune aging, including serum pro-inflammatory cytokine levels and blood cell subsets, were assessed. Five subjects reported potential adverse side effects; in the RAPA group, these were limited to facial rash (1 subject), stomatitis (1 subject) and gastrointestinal issues (2 subjects) whereas placebo treated subjects only reported stomatitis (1 subject). Although no other adverse events were reported, statistically

  4. Biased random key genetic algorithm with insertion and gender selection for capacitated vehicle routing problem with time windows

    Science.gov (United States)

    Rochman, Auliya Noor; Prasetyo, Hari; Nugroho, Munajat Tri

    2017-06-01

    Vehicle Routing Problem (VRP) often occurs when the manufacturers need to distribute their product to some customers/outlets. The distribution process is typically restricted by the capacity of the vehicle and the working hours at the distributor. This type of VRP is also known as Capacitated Vehicle Routing Problem with Time Windows (CVRPTW). A Biased Random Key Genetic Algorithm (BRKGA) was designed and coded in MATLAB to solve the CVRPTW case of soft drink distribution. The standard BRKGA was then modified by applying chromosome insertion into the initial population and defining chromosome gender for parent undergoing crossover operation. The performance of the established algorithms was then compared to a heuristic procedure for solving a soft drink distribution. Some findings are revealed (1) the total distribution cost of BRKGA with insertion (BRKGA-I) results in a cost saving of 39% compared to the total cost of heuristic method, (2) BRKGA with the gender selection (BRKGA-GS) could further improve the performance of the heuristic method. However, the BRKGA-GS tends to yield worse results compared to that obtained from the standard BRKGA.

  5. Sequence-Based Prediction of RNA-Binding Proteins Using Random Forest with Minimum Redundancy Maximum Relevance Feature Selection

    Directory of Open Access Journals (Sweden)

    Xin Ma

    2015-01-01

    Full Text Available The prediction of RNA-binding proteins is one of the most challenging problems in computation biology. Although some studies have investigated this problem, the accuracy of prediction is still not sufficient. In this study, a highly accurate method was developed to predict RNA-binding proteins from amino acid sequences using random forests with the minimum redundancy maximum relevance (mRMR method, followed by incremental feature selection (IFS. We incorporated features of conjoint triad features and three novel features: binding propensity (BP, nonbinding propensity (NBP, and evolutionary information combined with physicochemical properties (EIPP. The results showed that these novel features have important roles in improving the performance of the predictor. Using the mRMR-IFS method, our predictor achieved the best performance (86.62% accuracy and 0.737 Matthews correlation coefficient. High prediction accuracy and successful prediction performance suggested that our method can be a useful approach to identify RNA-binding proteins from sequence information.

  6. Optimal Subset Selection of Time-Series MODIS Images and Sample Data Transfer with Random Forests for Supervised Classification Modelling.

    Science.gov (United States)

    Zhou, Fuqun; Zhang, Aining

    2016-10-25

    Nowadays, various time-series Earth Observation data with multiple bands are freely available, such as Moderate Resolution Imaging Spectroradiometer (MODIS) datasets including 8-day composites from NASA, and 10-day composites from the Canada Centre for Remote Sensing (CCRS). It is challenging to efficiently use these time-series MODIS datasets for long-term environmental monitoring due to their vast volume and information redundancy. This challenge will be greater when Sentinel 2-3 data become available. Another challenge that researchers face is the lack of in-situ data for supervised modelling, especially for time-series data analysis. In this study, we attempt to tackle the two important issues with a case study of land cover mapping using CCRS 10-day MODIS composites with the help of Random Forests' features: variable importance, outlier identification. The variable importance feature is used to analyze and select optimal subsets of time-series MODIS imagery for efficient land cover mapping, and the outlier identification feature is utilized for transferring sample data available from one year to an adjacent year for supervised classification modelling. The results of the case study of agricultural land cover classification at a regional scale show that using only about a half of the variables we can achieve land cover classification accuracy close to that generated using the full dataset. The proposed simple but effective solution of sample transferring could make supervised modelling possible for applications lacking sample data.

  7. Selective serotonin reuptake inhibitors (SSRIs) for post-partum depression (PPD): a systematic review of randomized clinical trials.

    Science.gov (United States)

    De Crescenzo, Franco; Perelli, Federica; Armando, Marco; Vicari, Stefano

    2014-01-01

    The treatment of postpartum depression with selective serotonin reuptake inhibitors (SSRIs) has been claimed to be both efficacious and well tolerated, but no recent systematic reviews have been conducted. A qualitative systematic review of randomized clinical trials on women with postpartum depression comparing SSRIs to placebo and/or other treatments was performed. A comprehensive literature search of online databases, the bibliographies of published articles and grey literature were conducted. Data on efficacy, acceptability and tolerability were extracted and the quality of the trials was assessed. Six randomised clinical trials, comprising 595 patients, met quality criteria for inclusion in the analysis. Cognitive-behavioural intervention, psychosocial community-based intervention, psychodynamic therapy, cognitive behavioural therapy, a second-generation tricyclic antidepressant and placebo were used as comparisons. All studies demonstrated higher response and remission rates among those treated with SSRIs and greater mean changes on depression scales, although findings were not always statistically significant. Dropout rates were high in three of the trials but similar among treatment and comparison groups. In general, SSRIs were well tolerated and trial quality was good. There are few trials, patients included in the trials were not representative of all patients with postpartum depression, dropout rates in three trials were high, and long-term efficacy and tolerability were assessed in only two trials. SSRIs appear to be efficacious and well tolerated in the treatment of postpartum depression, but the available evidence fails to demonstrate a clear superiority over other treatments. © 2013 Elsevier B.V. All rights reserved.

  8. Effectiveness of selective risk based screening for Gestational Diabetes (GDM) in Malaysia: A retrospective cohort study based on the National Obstetric Registry (NOR) of Malaysia.

    Science.gov (United States)

    Muniswaran, G; Soelar, S A; Karalasingam, S D; Bujang, M A; Jeganathan, R; Suharjono, H

    2017-02-01

    Gestational diabetes (GDM) has significant maternal and foetal implications. screening allows active interventions which significantly improves pregnancy outcomes. Despite World Health Organization (WHO), FIGO and National Institute of clinical Excellence (NIcE) recommendations for universal screening especially among high risk population; Malaysia currently adopts a selective risk based screening for GDM. the objective is to audit the effectiveness of the current practice of selective risk based screening in detection of GDM in Malaysia. this is a retrospective cohort study based on the National Obstetric Registry (NOR) which comprises of 14 major tertiary hospitals in Malaysia. the study period was from 1st January 2011 till 31st December 2012 and a total of 22,044 patients with GDM were analysed. Logistic regression analysis was used to calculate the crude odd ratio. the incidence of GDM in Malaysia is 8.4%. Maternal age of ≥25, booking bMI ≥27kg/m2, booking weight ≥80kg and previous hypertension are non-significant risk of developing GDM in Malaysia. Parity 5 and more was only associated with an odds-ratio of 1.02 (95% confidence Interval: 0.90-1.17) as compared to parity below 5. the association of women with previous stillbirth with GDM was not significant. current risk based screening for GDM based on maternal age, booking bMI, weight and hypertension is inappropriate. An ideal screening tool should precede disease complications, which is the novel objective of screening. Universal screening for GDM in Malaysia may be a more accurate measure, especially with regards to reducing maternal and foetal complications.

  9. The Long-Term Effectiveness of a Selective, Personality-Targeted Prevention Program in Reducing Alcohol Use and Related Harms: A Cluster Randomized Controlled Trial

    Science.gov (United States)

    Newton, Nicola C.; Conrod, Patricia J.; Slade, Tim; Carragher, Natacha; Champion, Katrina E.; Barrett, Emma L.; Kelly, Erin V.; Nair, Natasha K.; Stapinski, Lexine; Teesson, Maree

    2016-01-01

    Background: This study investigated the long-term effectiveness of Preventure, a selective personality-targeted prevention program, in reducing the uptake of alcohol, harmful use of alcohol, and alcohol-related harms over a 3-year period. Methods: A cluster randomized controlled trial was conducted to assess the effectiveness of Preventure.…

  10. Evaluation of Randomly Selected Completed Medical Records Sheets in Teaching Hospitals of Jahrom University of Medical Sciences, 2009

    Directory of Open Access Journals (Sweden)

    Mohammad Parsa Mahjob

    2011-06-01

    Full Text Available Background and objective: Medical record documentation, often use to protect the patients legal rights, also providing information for medical researchers, general studies, education of health care staff and qualitative surveys is used. There is a need to control the amount of data entered in the medical record sheets of patients, considering the completion of these sheets is often carried out after completion of service delivery to the patients. Therefore, in this study the prevalence of completeness of medical history, operation reports, and physician order sheets by different documentaries in Jahrom teaching hospitals during year 2009 was analyzed. Methods and Materials: In this descriptive / retrospective study, the 400 medical record sheets of the patients from two teaching hospitals affiliated to Jahrom medical university was randomly selected. The tool of data collection was a checklist based on the content of medical history sheet, operation report and physician order sheets. The data were analyzed by SPSS (Version10 software and Microsoft Office Excel 2003. Results: Average of personal (Demography data entered in medical history, physician order and operation report sheets which is done by department's secretaries were 32.9, 35.8 and 40.18 percent. Average of clinical data entered by physician in medical history sheet is 38 percent. Surgical data entered by the surgeon in operation report sheet was 94.77 percent. Average of data entered by operation room's nurse in operation report sheet was 36.78 percent; Average of physician order data in physician order sheet entered by physician was 99.3 percent. Conclusion: According to this study, the rate of completed record papers reviewed by documentary in Jahrom teaching hospitals were not desirable and in some cases were very weak and incomplete. This deficiency was due to different reason such as medical record documentaries negligence, lack of adequate education for documentaries, High work

  11. Water chemistry in 179 randomly selected Swedish headwater streams related to forest production, clear-felling and climate.

    Science.gov (United States)

    Löfgren, Stefan; Fröberg, Mats; Yu, Jun; Nisell, Jakob; Ranneby, Bo

    2014-12-01

    From a policy perspective, it is important to understand forestry effects on surface waters from a landscape perspective. The EU Water Framework Directive demands remedial actions if not achieving good ecological status. In Sweden, 44 % of the surface water bodies have moderate ecological status or worse. Many of these drain catchments with a mosaic of managed forests. It is important for the forestry sector and water authorities to be able to identify where, in the forested landscape, special precautions are necessary. The aim of this study was to quantify the relations between forestry parameters and headwater stream concentrations of nutrients, organic matter and acid-base chemistry. The results are put into the context of regional climate, sulphur and nitrogen deposition, as well as marine influences. Water chemistry was measured in 179 randomly selected headwater streams from two regions in southwest and central Sweden, corresponding to 10 % of the Swedish land area. Forest status was determined from satellite images and Swedish National Forest Inventory data using the probabilistic classifier method, which was used to model stream water chemistry with Bayesian model averaging. The results indicate that concentrations of e.g. nitrogen, phosphorus and organic matter are related to factors associated with forest production but that it is not forestry per se that causes the excess losses. Instead, factors simultaneously affecting forest production and stream water chemistry, such as climate, extensive soil pools and nitrogen deposition, are the most likely candidates The relationships with clear-felled and wetland areas are likely to be direct effects.

  12. Exposure–response relationships for select cancer and non-cancer health outcomes in a cohort of US firefighters from San Francisco, Chicago and Philadelphia (1950–2009)

    Science.gov (United States)

    Daniels, Robert D.; Bertke, Stephen; Dahm, Matthew M.; Yiin, James H.; Kubale, Travis L.; Hales, Thomas R.; Baris, Dalsu; Zahm, Shelia H.; Beaumont, James J.; Waters, Kathleen M.; Pinkerton, Lynne E.

    2015-01-01

    Objectives To examine exposure–response relationships between surrogates of firefighting exposure and select outcomes among previously studied US career firefighters. Methods Eight cancer and four non-cancer outcomes were examined using conditional logistic regression. Incidence density sampling was used to match each case to 200 controls on attained age. Days accrued in firefighting assignments (exposed-days), run totals (fire-runs) and run times (fire-hours) were used as exposure surrogates. HRs comparing 75th and 25th centiles of lagged cumulative exposures were calculated using loglinear, linear, log-quadratic, power and restricted cubic spline general relative risk models. Piecewise constant models were used to examine risk differences by time since exposure, age at exposure and calendar period. Results Among 19 309 male firefighters eligible for the study, there were 1333 cancer deaths and 2609 cancer incidence cases. Significant positive associations between fire-hours and lung cancer mortality and incidence were evident. A similar relation between leukaemia mortality and fire-runs was also found. The lung cancer associations were nearly linear in cumulative exposure, while the association with leukaemia mortality was attenuated at higher exposure levels and greater for recent exposures. Significant negative associations were evident for the exposure surrogates and colorectal and prostate cancers, suggesting a healthy worker survivor effect possibly enhanced by medical screening. Conclusions Lung cancer and leukaemia mortality risks were modestly increasing with firefighter exposures. These findings add to evidence of a causal association between firefighting and cancer. Nevertheless, small effects merit cautious interpretation. We plan to continue to follow the occurrence of disease and injury in this cohort. PMID:25673342

  13. Association of lactase persistence genotype with milk consumption, obesity and blood pressure: a Mendelian randomization study in the 1982 Pelotas (Brazil) Birth Cohort, with a systematic review and meta-analysis.

    Science.gov (United States)

    Hartwig, Fernando Pires; Horta, Bernardo Lessa; Smith, George Davey; de Mola, Christian Loret; Victora, Cesar Gomes

    2016-10-01

    Milk intake has been associated with lower blood pressure (BP) in observational studies, and randomized controlled trials suggested that milk-derived tripeptides have BP-lowering effects. Milk intake has also been associated with body mass index (BMI). Nevertheless, it is unclear whether increasing milk consumption would reduce BP in the general population. We investigated the association of milk intake with obesity and BP using genetically-defined lactase persistence (LP) based on the rs4988235 polymorphism in a Mendelian randomization design in the 1982 Pelotas (Southern Brazil) Birth Cohort. These results were combined with published reports identified through a systematic review using meta-analysis. In the 1982 Pelotas Birth Cohort, milk intake was 42 [95% confidence interval (CI): 18; 67) ml/day higher in LP individuals. In conventional observational analysis, each 1-dl/day increase in milk intake was associated with -0.26 (95% CI: -0.33; -0.19) kg/m 2 in BMI and -0.31 (95% CI: -0.46; -0.16) and -0.35 (95% CI: -0.46; -0.23) mmHg in systolic and diastolic BP, respectively. These results were not corroborated when analysing LP status, but confidence intervals were large. In random effects meta-analysis, LP individuals presented higher BMI [0.17 (95% CI: 0.07; 0.27) kg/m 2 ] and higher odds of overweight-obesity [1.09 (95% CI: 1.02; 1.17)]. There were no reliable associations for BP. Our study supports that LP is positively associated with obesity, suggesting that the negative association of milk intake with obesity is likely due to limitations of conventional observational studies. Our findings also do not support that increased milk intake leads to lower BP. © The Author 2016. Published by Oxford University Press on behalf of the International Epidemiological Association.

  14. 10-Year Mortality Outcome of a Routine Invasive Strategy Versus a Selective Invasive Strategy in Non-ST-Segment Elevation Acute Coronary Syndrome: The British Heart Foundation RITA-3 Randomized Trial.

    Science.gov (United States)

    Henderson, Robert A; Jarvis, Christopher; Clayton, Tim; Pocock, Stuart J; Fox, Keith A A

    2015-08-04

    The RITA-3 (Third Randomised Intervention Treatment of Angina) trial compared outcomes of a routine early invasive strategy (coronary arteriography and myocardial revascularization, as clinically indicated) to those of a selective invasive strategy (coronary arteriography for recurrent ischemia only) in patients with non-ST-segment elevation acute coronary syndrome (NSTEACS). At a median of 5 years' follow-up, the routine invasive strategy was associated with a 24% reduction in the odds of all-cause mortality. This study reports 10-year follow-up outcomes of the randomized cohort to determine the impact of a routine invasive strategy on longer-term mortality. We randomized 1,810 patients with NSTEACS to receive routine invasive or selective invasive strategies. All randomized patients had annual follow-up visits up to 5 years, and mortality was documented thereafter using data from the Office of National Statistics. Over 10 years, there were no differences in mortality between the 2 groups (all-cause deaths in 225 [25.1%] vs. 232 patients [25.4%]: p = 0.94; and cardiovascular deaths in 135 [15.1%] vs. 147 patients [16.1%]: p = 0.65 in the routine invasive and selective invasive groups, respectively). Multivariate analysis identified several independent predictors of 10-year mortality: age, previous myocardial infarction, heart failure, smoking status, diabetes, heart rate, and ST-segment depression. A modified post-discharge Global Registry of Acute Coronary Events (GRACE) score was used to calculate an individual risk score for each patient and to form low-risk, medium-risk, and high-risk groups. Risk of death within 10 years varied markedly from 14.4 % in the low-risk group to 56.2% in the high-risk group. This mortality trend did not depend on the assigned treatment strategy. The advantage of reduced mortality of routine early invasive strategy seen at 5 years was attenuated during later follow-up, with no evidence of a difference in outcome at 10 years

  15. Convergence analysis for Latin-hypercube lattice-sample selection strategies for 3D correlated random hydraulic-conductivity fields

    OpenAIRE

    Simuta-Champo, R.; Herrera-Zamarrón, G. S.

    2010-01-01

    The Monte Carlo technique provides a natural method for evaluating uncertainties. The uncertainty is represented by a probability distribution or by related quantities such as statistical moments. When the groundwater flow and transport governing equations are solved and the hydraulic conductivity field is treated as a random spatial function, the hydraulic head, velocities and concentrations also become random spatial functions. When that is the case, for the stochastic simulation of groundw...

  16. Two simple strategies (adding a logo or a senior faculty's signature) failed to improve patient participation rates in a cohort study: randomized trial

    NARCIS (Netherlands)

    van Wonderen, Karina E.; Mohrs, Jacob; Jff, Machteld I.; Bindels, Patrick J. E.; ter Riet, Gerben

    2008-01-01

    Background: Patient participation in research studies is often difficult to achieve, and efforts to increase participation rates fail frequently. Given the paucity of evidence on interventions aimed at improving patient participation, we conducted a randomized trial. Objectives: The first was to

  17. A comparison of random forest and its Gini importance with standard chemometric methods for the feature selection and classification of spectral data

    Directory of Open Access Journals (Sweden)

    Himmelreich Uwe

    2009-07-01

    Full Text Available Abstract Background Regularized regression methods such as principal component or partial least squares regression perform well in learning tasks on high dimensional spectral data, but cannot explicitly eliminate irrelevant features. The random forest classifier with its associated Gini feature importance, on the other hand, allows for an explicit feature elimination, but may not be optimally adapted to spectral data due to the topology of its constituent classification trees which are based on orthogonal splits in feature space. Results We propose to combine the best of both approaches, and evaluated the joint use of a feature selection based on a recursive feature elimination using the Gini importance of random forests' together with regularized classification methods on spectral data sets from medical diagnostics, chemotaxonomy, biomedical analytics, food science, and synthetically modified spectral data. Here, a feature selection using the Gini feature importance with a regularized classification by discriminant partial least squares regression performed as well as or better than a filtering according to different univariate statistical tests, or using regression coefficients in a backward feature elimination. It outperformed the direct application of the random forest classifier, or the direct application of the regularized classifiers on the full set of features. Conclusion The Gini importance of the random forest provided superior means for measuring feature relevance on spectral data, but – on an optimal subset of features – the regularized classifiers might be preferable over the random forest classifier, in spite of their limitation to model linear dependencies only. A feature selection based on Gini importance, however, may precede a regularized linear classification to identify this optimal subset of features, and to earn a double benefit of both dimensionality reduction and the elimination of noise from the classification task.

  18. Affinity selection of Nipah and Hendra virus-related vaccine candidates from a complex random peptide library displayed on bacteriophage virus-like particles

    Energy Technology Data Exchange (ETDEWEB)

    Peabody, David S.; Chackerian, Bryce; Ashley, Carlee; Carnes, Eric; Negrete, Oscar

    2017-01-24

    The invention relates to virus-like particles of bacteriophage MS2 (MS2 VLPs) displaying peptide epitopes or peptide mimics of epitopes of Nipah Virus envelope glycoprotein that elicit an immune response against Nipah Virus upon vaccination of humans or animals. Affinity selection on Nipah Virus-neutralizing monoclonal antibodies using random sequence peptide libraries on MS2 VLPs selected peptides with sequence similarity to peptide sequences found within the envelope glycoprotein of Nipah itself, thus identifying the epitopes the antibodies recognize. The selected peptide sequences themselves are not necessarily identical in all respects to a sequence within Nipah Virus glycoprotein, and therefore may be referred to as epitope mimics VLPs displaying these epitope mimics can serve as vaccine. On the other hand, display of the corresponding wild-type sequence derived from Nipah Virus and corresponding to the epitope mapped by affinity selection, may also be used as a vaccine.

  19. Cohort profile

    DEFF Research Database (Denmark)

    Tollånes, Mette C; Strandberg-Larsen, Katrine; Forthun, Ingeborg

    2016-01-01

    PURPOSE: The purpose of MOthers and BAbies in Norway and Denmark cerebral palsy (MOBAND-CP) was to study CP aetiology in a prospective design. PARTICIPANTS: MOBAND-CP is a cohort of more than 210 000 children, created as a collaboration between the world's two largest pregnancy cohorts-the Norweg......PURPOSE: The purpose of MOthers and BAbies in Norway and Denmark cerebral palsy (MOBAND-CP) was to study CP aetiology in a prospective design. PARTICIPANTS: MOBAND-CP is a cohort of more than 210 000 children, created as a collaboration between the world's two largest pregnancy cohorts......-the Norwegian Mother and Child Cohort study (MoBa) and the Danish National Birth Cohort. MOBAND-CP includes maternal interview/questionnaire data collected during pregnancy and follow-up, plus linked information from national health registries. FINDINGS TO DATE: Initial harmonisation of data from the 2 cohorts...... has created 140 variables for children and their mothers. In the MOBAND-CP cohort, 438 children with CP have been identified through record linkage with validated national registries, providing by far the largest such sample with prospectively collected detailed pregnancy data. Several studies...

  20. Low body weight and type of protease inhibitor predict discontinuation and treatment-limiting adverse drug reactions among HIV-infected patients starting a protease inhibitor regimen: consistent results from a randomized trial and an observational cohort

    DEFF Research Database (Denmark)

    Kirk, O; Gerstoft, J; Pedersen, C

    2001-01-01

    OBJECTIVES: To assess predictors for discontinuation and treatment-limiting adverse drug reactions (TLADR) among patients starting their first protease inhibitor (PI). METHODS: Data on patients starting a PI regimen (indinavir, ritonavir, ritonavir/saquinavir and saquinavir hard gel) in a randomi......OBJECTIVES: To assess predictors for discontinuation and treatment-limiting adverse drug reactions (TLADR) among patients starting their first protease inhibitor (PI). METHODS: Data on patients starting a PI regimen (indinavir, ritonavir, ritonavir/saquinavir and saquinavir hard gel....... Low body weight and initiation of ritonavir relative to other PIs were associated with an increased risk of TLADRs. Very consistent results were found in a randomized trial and an observational cohort....

  1. Selective cyclooxygenase-2 inhibitor use and progression of renal function in patients with chronic kidney disease: a single-center retrospective cohort study

    Directory of Open Access Journals (Sweden)

    Kaewput W

    2016-11-01

    Full Text Available Wisit Kaewput,1,2 Preedee Disorn,2 Bancha Satirapoj2 1Department of Military and Community Medicine, Phramongkutklao College of Medicine, 2Department of Medicine, Phramongkutklao Hospital and College of Medicine, Bangkok, Thailand Background: The use of selective COX-2 (sCOX-2 inhibitors with acute kidney injury, salt water retention, and cardiovascular events have been correlated in subjects with normal kidney function, but sCOX-2 inhibitor use concerning the progression of chronic kidney disease (CKD remains uncertain. Objectives: To determine the progression of renal function and electrolyte abnormalities among CKD patients after using sCOX-2 inhibitors during short- and long-term periods. Methods: The study employed a retrospective cohort design comprising all types of CKD patients with and without sCOX-2 inhibitors (celecoxib and etoricoxib. Data collected included medical data, estimated glomerular filtration rate (eGFR, and serum electrolytes at 3 and 6 months between January 2009 and January 2014. Subjects attended the outpatient clinic and were then followed up until discontinuation of the drugs at years 1 and 2 until May 2016. Results: Ninety-two CKD patients on sCOX-2 inhibitors and 92 CKD patients without sCOX-2 inhibitors were included. The sCOX-2 inhibitor group showed more decline in eGFR than the control group at 3 and 6 months of follow-up (–8.27±9.75 vs –1.64±6.05 mL/min/1.73 m2, P<0.001 and –12.36±6.48 vs –4.31±5.11 mL/min/1.73 m2, P=0.001, respectively and at 1 and 2 years of follow-up after subjects discontinued sCOX-2 (–6.84±10.34 vs –1.61±8.93 mL/min/1.73 m2, P=0.004 and –10.26±10.19 vs –5.12±8.61 mL/min/1.73 m2, P=0.005, respectively. In addition, the sCOX-2 inhibitor group had significantly more increased serum potassium during the study follow-up than the control group. Conclusion: The sCOX-2 inhibitors are associated with an increased risk for rapid eGFR decline and hyperkalemia in both the

  2. Randomized trial of switching from prescribed non-selective non-steroidal anti-inflammatory drugs to prescribed celecoxib

    DEFF Research Database (Denmark)

    Macdonald, Thomas M; Hawkey, Chris J; Ford, Ian

    2017-01-01

    BACKGROUND: Selective cyclooxygenase-2 inhibitors and conventional non-selective non-steroidal anti-inflammatory drugs (nsNSAIDs) have been associated with adverse cardiovascular (CV) effects. We compared the CV safety of switching to celecoxib vs. continuing nsNSAID therapy in a European setting...

  3. Empirical versus Random Item Selection in the Design of Intelligence Test Short Forms--The WISC-R Example.

    Science.gov (United States)

    Goh, David S.

    1979-01-01

    The advantages of using psychometric thoery to design short forms of intelligence tests are demonstrated by comparing such usage to a systematic random procedure that has previously been used. The Wechsler Intelligence Scale for Children Revised (WISC-R) Short Form is presented as an example. (JKS)

  4. Diagnosing gestational diabetes mellitus in the Danish National Birth Cohort.

    Science.gov (United States)

    Olsen, Sjurdur F; Houshmand-Oeregaard, Azedeh; Granström, Charlotta; Langhoff-Roos, Jens; Damm, Peter; Bech, Bodil H; Vaag, Allan A; Zhang, Cuilin

    2017-05-01

    The Danish National Birth Cohort (DNBC) contains comprehensive information on diet, lifestyle, constitutional and other major characteristics of women during pregnancy. It provides a unique source for studies on health consequences of gestational diabetes mellitus. Our aim was to identify and validate the gestational diabetes mellitus cases in the cohort. We extracted clinical information from hospital records for 1609 pregnancies included in the Danish National Birth Cohort with a diagnosis of diabetes during or before pregnancy registered in the Danish National Patient Register and/or from a Danish National Birth Cohort interview during pregnancy. We further validated the diagnosis of gestational diabetes mellitus in 2126 randomly selected pregnancies from the entire Danish National Birth Cohort. From the individual hospital records, an expert panel evaluated gestational diabetes mellitus status based on results from oral glucose tolerance tests, fasting blood glucose and Hb1c values, as well as diagnoses made by local obstetricians. The audit categorized 783 pregnancies as gestational diabetes mellitus, corresponding to 0.89% of the 87 792 pregnancies for which a pregnancy interview for self-reported diabetes in pregnancy was available. From the randomly selected group the combined information from register and interviews could correctly identify 96% (95% CI 80-99.9%) of all cases in the entire Danish National Birth Cohort population. Positive predictive value, however, was only 59% (56-61%). The combined use of data from register and interview provided a high sensitivity for gestational diabetes mellitus diagnosis. The low positive predictive value, however, suggests that systematic validation by hospital record review is essential not to underestimate the health consequences of gestational diabetes mellitus in future studies. © 2016 Nordic Federation of Societies of Obstetrics and Gynecology.

  5. Comparison of Low-Dose Rosuvastatin with Atorvastatin in Lipid-Lowering Efficacy and Safety in a High-Risk Pakistani Cohort: An Open-Label Randomized Trial

    Directory of Open Access Journals (Sweden)

    Abdul Rehman Arshad

    2014-01-01

    Full Text Available Background. Treatment of hyperlipidemia is helpful in both primary and secondary prevention of coronary heart disease and stroke. Aim. To compare lipid-lowering efficacy of rosuvastatin with atorvastatin. Methodology. This open-label randomized controlled trial was carried out at 1 Mountain Medical Battalion from September 2012 to August 2013 on patients with type 2 diabetes, hypertension, myocardial infarction, or stroke, meriting treatment with a statin. Those with secondary causes of dyslipidemia were excluded. Blood samples for estimation of serum total cholesterol, triglycerides, HDL-C, and LDL-C were collected after a 12-hour fast. Patients were randomly allocated to receive either atorvastatin 10 mg HS or rosuvastatin 5 mg HS daily. Lipid levels were rechecked after six weeks. Results. Atorvastatin was used in 63 patients and rosuvastatin in 66. There was a greater absolute and percent reduction in serum LDL-C levels with rosuvastatin as compared to atorvastatin (0.96 versus 0.54 mg/dL; P=0.011 and 24.34 versus 13.66%; P=0.045, whereas reduction in all other fractions was equal. Myalgias were seen in 5 (7.94% patients treated with atorvastatin and 8 (12.12% patients treated with rosuvastatin (P: 0.432. Conclusion. Rosuvastatin produces a greater reduction in serum LDL-C levels and should therefore be preferred over atorvastatin.

  6. Do vouchers lead to sorting under random private-school selection? Evidence from the Milwaukee voucher program

    OpenAIRE

    Chakrabarti, Rajashri

    2009-01-01

    This paper analyzes the effect of school vouchers on student sorting - defined as a flight to private schools by high-income and committed public-school students - and whether vouchers can be designed to reduce or eliminate it. Much of the existing literature investigates sorting in cases where private schools can screen students. However, publicly funded U.S. voucher programs require a private school to accept all students unless it is oversubscribed and to pick students randomly if it is ov...

  7. The Danish National Birth Cohort

    DEFF Research Database (Denmark)

    Andersen, Anne-Marie Nybo; Olsen, Jørn

    2011-01-01

    , physical exercise, working conditions, medication and infections during pregnancy, and environmental possible toxins. The study designs cover straightforward cohort analyses, case-control studies and sub-cohort analyses with enriched data collection. CONCLUSION: So far, the Danish National Birth Cohort has......INTRODUCTION: In this review a selection of studies published during the period 2002-2010, based on data from the Danish National Birth Cohort linked with other health registers, is described. Illustrative examples of studies addressing perinatal health outcomes (pregnancy complications and fetal...... that this investment in epidemiologic infrastructure was well spent. The existence of the Danish National Birth Cohort together with other cohorts and national registers has given Denmark a leading position in reproductive epidemiology....

  8. SNPs selected by information content outperform randomly selected microsatellite loci for delineating genetic identification and introgression in the endangered dark European honeybee (Apis mellifera mellifera).

    Science.gov (United States)

    Muñoz, Irene; Henriques, Dora; Jara, Laura; Johnston, J Spencer; Chávez-Galarza, Julio; De La Rúa, Pilar; Pinto, M Alice

    2017-07-01

    The honeybee (Apis mellifera) has been threatened by multiple factors including pests and pathogens, pesticides and loss of locally adapted gene complexes due to replacement and introgression. In western Europe, the genetic integrity of the native A. m. mellifera (M-lineage) is endangered due to trading and intensive queen breeding with commercial subspecies of eastern European ancestry (C-lineage). Effective conservation actions require reliable molecular tools to identify pure-bred A. m. mellifera colonies. Microsatellites have been preferred for identification of A. m. mellifera stocks across conservation centres. However, owing to high throughput, easy transferability between laboratories and low genotyping error, SNPs promise to become popular. Here, we compared the resolving power of a widely utilized microsatellite set to detect structure and introgression with that of different sets that combine a variable number of SNPs selected for their information content and genomic proximity to the microsatellite loci. Contrary to every SNP data set, microsatellites did not discriminate between the two lineages in the PCA space. Mean introgression proportions were identical across the two marker types, although at the individual level, microsatellites' performance was relatively poor at the upper range of Q-values, a result reflected by their lower precision. Our results suggest that SNPs are more accurate and powerful than microsatellites for identification of A. m. mellifera colonies, especially when they are selected by information content. © 2016 John Wiley & Sons Ltd.

  9. Effects of one versus two bouts of moderate intensity physical activity on selective attention during a school morning in Dutch primary schoolchildren: A randomized controlled trial.

    Science.gov (United States)

    Altenburg, Teatske M; Chinapaw, Mai J M; Singh, Amika S

    2016-10-01

    Evidence suggests that physical activity is positively related to several aspects of cognitive functioning in children, among which is selective attention. To date, no information is available on the optimal frequency of physical activity on cognitive functioning in children. The current study examined the acute effects of one and two bouts of moderate-intensity physical activity on children's selective attention. Randomized controlled trial (ISRCTN97975679). Thirty boys and twenty-six girls, aged 10-13 years, were randomly assigned to three conditions: (A) sitting all morning working on simulated school tasks; (B) one 20-min physical activity bout after 90min; and (C) two 20-min physical activity bouts, i.e. at the start and after 90min. Selective attention was assessed at five time points during the morning (i.e. at baseline and after 20, 110, 130 and 220min), using the 'Sky Search' subtest of the 'Test of Selective Attention in Children'. We used GEE analysis to examine differences in Sky Search scores between the three experimental conditions, adjusting for school, baseline scores, self-reported screen time and time spent in sports. Children who performed two 20-min bouts of moderate-intensity physical activity had significantly better Sky Search scores compared to children who performed one physical activity bout or remained seated the whole morning (B=-0.26; 95% CI=[-0.52; -0.00]). Our findings support the importance of repeated physical activity during the school day for beneficial effects on selective attention in children. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  10. Neonatal Vitamin D Levels in Relation to Risk of Overweight at 7 Years in the Danish D-Tect Case-Cohort Study

    DEFF Research Database (Denmark)

    Jensen, Camilla B.; Lundqvist, Marika; Sørensen, Thorkild I. A.

    2017-01-01

    Background: Vitamin D level in pregnancy may be associated with risk of overweight in the offspring later in life. Methods: In a case-cohort study based on Danish biobanks and registers we examined the association between 25-hydroxy-vitamin D (25(OH)D) level at birth and overweight at 7 years....... Cases of overweight (n = 871) were randomly selected among 7-year-old children from the Copenhagen School Health Records Register (CSHRR) with a BMI above the 90th percentile. The cohort (n = 1,311) was a random sample selected among all Danish children born during the same period. Neonatal 25(OH...

  11. The concentration of heavy metals: zinc, cadmium, lead, copper, mercury, iron and calcium in head hair of a randomly selected sample of Kenyan people

    International Nuclear Information System (INIS)

    Wandiga, S.O.; Jumba, I.O.

    1982-01-01

    An intercomparative analysis of the concentration of heavy metals:zinc, cadmium, lead, copper, mercury, iron and calcium in head hair of a randomly selected sample of Kenyan people using the techniques of atomic absorption spectrophotometry (AAS) and differential pulse anodic stripping voltammetry (DPAS) has been undertaken. The percent relative standard deviation for each sample analysed using either of the techniques show good sensitivity and correlation between the techniques. The DPAS was found to be slightly sensitive than the AAs instrument used. The recalculated body burden rations of Cd to Zn, Pb to Fe reveal no unusual health impairement symptoms and suggest a relatively clean environment in Kenya.(author)

  12. Cohort profile: the National Health Insurance Service-National Health Screening Cohort (NHIS-HEALS) in Korea.

    Science.gov (United States)

    Seong, Sang Cheol; Kim, Yeon-Yong; Park, Sue K; Khang, Young Ho; Kim, Hyeon Chang; Park, Jong Heon; Kang, Hee-Jin; Do, Cheol-Ho; Song, Jong-Sun; Lee, Eun-Joo; Ha, Seongjun; Shin, Soon Ae; Jeong, Seung-Lyeal

    2017-09-24

    The National Health Insurance Service-Health Screening Cohort (NHIS-HEALS) is a cohort of participants who participated in health screening programmes provided by the NHIS in the Republic of Korea. The NHIS constructed the NHIS-HEALS cohort database in 2015. The purpose of this cohort is to offer relevant and useful data for health researchers, especially in the field of non-communicable diseases and health risk factors, and policy-maker. To construct the NHIS-HEALS database, a sample cohort was first selected from the 2002 and 2003 health screening participants, who were aged between 40 and 79 in 2002 and followed up through 2013. This cohort included 514 866 health screening participants who comprised a random selection of 10% of all health screening participants in 2002 and 2003. The age-standardised prevalence of anaemia, diabetes mellitus, hypertension, obesity, hypercholesterolaemia and abnormal urine protein were 9.8%, 8.2%, 35.6%, 2.7%, 14.2% and 2.0%, respectively. The age-standardised mortality rate for the first 2 years (through 2004) was 442.0 per 100 000 person-years, while the rate for 10 years (through 2012) was 865.9 per 100 000 person-years. The most common cause of death was malignant neoplasm in both sexes (364.1 per 100 000 person-years for men, 128.3 per 100 000 person-years for women). This database can be used to study the risk factors of non-communicable diseases and dental health problems, which are important health issues that have not yet been fully investigated. The cohort will be maintained and continuously updated by the NHIS. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  13. Cohort profile

    DEFF Research Database (Denmark)

    Maret-Ouda, John; Wahlin, Karl; Artama, Miia

    2017-01-01

    Purpose: To describe a newly created all-Nordic cohort of patients with gastro-oesophageal reflux disease (GORD), entitled the Nordic Antireflux Surgery Cohort (NordASCo), which will be used to compare participants having undergone antireflux surgery with those who have not regarding risk...... age at primary antireflux surgery ranged from 47 to 52 years in the different countries. The coding practices of GORD seem to have differed between the Nordic countries. Future plans: The NordASCo will initially be used to analyse the risk of developing known or potential GORD-related cancers, that is......, tumours of the oesophagus, stomach, larynx, pharynx and lung, and to evaluate the mortality in the short-term and long-term perspectives. Additionally, the cohort will be used to evaluate the risk of non-malignant respiratory conditions that might be caused by aspiration of gastric contents....

  14. Media Coverage, Journal Press Releases and Editorials Associated with Randomized and Observational Studies in High-Impact Medical Journals: A Cohort Study.

    Directory of Open Access Journals (Sweden)

    Michael T M Wang

    Full Text Available Publication of clinical research findings in prominent journals influences health beliefs and medical practice, in part by engendering news coverage. Randomized controlled trials (RCTs should be most influential in guiding clinical practice. We determined whether study design of clinical research published in high-impact journals influences media coverage.We compared the incidence and amount of media coverage of RCTs with that of observational studies published in the top 7 medical journals between 1 January 2013 and 31 March 2013. We specifically assessed media coverage of the most rigorous RCTs, those with >1000 participants that reported 'hard' outcomes. There was no difference between RCTs and observational studies in coverage by major newspapers or news agencies, or in total number of news stories generated (all P>0.63. Large RCTs reporting 'hard' outcomes did not generate more news coverage than small RCTs that reported surrogate outcomes and observational studies (all P>0.32. RCTs were more likely than observational studies to attract a journal editorial (70% vs 46%, P = 0.003, but less likely to be the subject of a journal press release (17% vs 50%, P0.99, nor were they more likely to be the subject of a journal press release (14% vs 38%, P = 0.14.The design of clinical studies whose results are published in high-impact medical journals is not associated with the likelihood or amount of ensuing news coverage.

  15. Cohort Profile

    DEFF Research Database (Denmark)

    Jespersen, Sanne; Hønge, Bo Langhoff; Oliveira, Inés

    2014-01-01

    The West African country Guinea-Bissau is home to the world’s highest prevalence of HIV-2, and its HIV-1 prevalence is rising. Other chronic viral infections like human T-lymphotropic virus type 1 (HTLV-1) and hepatitis B virus are common as well. The Bissau HIV Cohort was started in 2007 to gain...... new insights into the overall effect of introducing antiretroviral treatment in a treatment-naı ̈ve population with concomitant infection with three retroviruses (HIV-1, HIV-2 and HTLV-1) and tuberculosis. The cohort includes patients from the HIV clinic at Hospital Nacional Sima ̃ o Mendes, the main...

  16. "Open mesh" or "strictly selected population" recruitment? The experience of the randomized controlled MeMeMe trial

    Directory of Open Access Journals (Sweden)

    Cortellini M

    2017-07-01

    Full Text Available Mauro Cortellini, Franco Berrino, Patrizia Pasanisi Department of Preventive & Predictive Medicine, Foundation IRCCS National Cancer Institute of Milan, Milan, Italy Abstract: Among randomized controlled trials (RCTs, trials for primary prevention require large samples and long follow-up to obtain a high-quality outcome; therefore the recruitment process and the drop-out rates largely dictate the adequacy of the results. We are conducting a Phase III trial on persons with metabolic syndrome to test the hypothesis that comprehensive lifestyle changes and/or metformin treatment prevents age-related chronic diseases (the MeMeMe trial, EudraCT number: 2012-005427-32, also registered on ClinicalTrials.gov [NCT02960711]. Here, we briefly analyze and discuss the reasons which may lead to participants dropping out from trials. In our experience, participants may back out of a trial for different reasons. Drug-induced side effects are certainly the most compelling reason. But what are the other reasons, relating to the participants’ perception of the progress of the trial which led them to withdraw after randomization? What about the time-dependent drop-out rate in primary prevention trials? The primary outcome of this analysis is the point of drop-out from trial, defined as the time from the randomization date to the withdrawal date. Survival functions were non-parametrically estimated using the product-limit estimator. The curves were statistically compared using the log-rank test (P=0.64, not significant. Researchers involved in primary prevention RCTs seem to have to deal with the paradox of the proverbial “short blanket syndrome”. Recruiting only highly motivated candidates might be useful for the smooth progress of the trial but it may lead to a very low enrollment rate. On the other hand, what about enrolling all the eligible subjects without considering their motivation? This might boost the enrollment rate, but it can lead to biased

  17. "Open mesh" or "strictly selected population" recruitment? The experience of the randomized controlled MeMeMe trial.

    Science.gov (United States)

    Cortellini, Mauro; Berrino, Franco; Pasanisi, Patrizia

    2017-01-01

    Among randomized controlled trials (RCTs), trials for primary prevention require large samples and long follow-up to obtain a high-quality outcome; therefore the recruitment process and the drop-out rates largely dictate the adequacy of the results. We are conducting a Phase III trial on persons with metabolic syndrome to test the hypothesis that comprehensive lifestyle changes and/or metformin treatment prevents age-related chronic diseases (the MeMeMe trial, EudraCT number: 2012-005427-32, also registered on ClinicalTrials.gov [NCT02960711]). Here, we briefly analyze and discuss the reasons which may lead to participants dropping out from trials. In our experience, participants may back out of a trial for different reasons. Drug-induced side effects are certainly the most compelling reason. But what are the other reasons, relating to the participants' perception of the progress of the trial which led them to withdraw after randomization? What about the time-dependent drop-out rate in primary prevention trials? The primary outcome of this analysis is the point of drop-out from trial, defined as the time from the randomization date to the withdrawal date. Survival functions were non-parametrically estimated using the product-limit estimator. The curves were statistically compared using the log-rank test ( P =0.64, not significant). Researchers involved in primary prevention RCTs seem to have to deal with the paradox of the proverbial "short blanket syndrome". Recruiting only highly motivated candidates might be useful for the smooth progress of the trial but it may lead to a very low enrollment rate. On the other hand, what about enrolling all the eligible subjects without considering their motivation? This might boost the enrollment rate, but it can lead to biased results on account of large proportions of drop-outs. Our experience suggests that participants do not change their mind depending on the allocation group (intervention or control). There is no single

  18. Evolution of Randomized Trials in Advanced/Metastatic Soft Tissue Sarcoma: End Point Selection, Surrogacy, and Quality of Reporting.

    Science.gov (United States)

    Zer, Alona; Prince, Rebecca M; Amir, Eitan; Abdul Razak, Albiruni

    2016-05-01

    Randomized controlled trials (RCTs) in soft tissue sarcoma (STS) have used varying end points. The surrogacy of intermediate end points, such as progression-free survival (PFS), response rate (RR), and 3-month and 6-month PFS (3moPFS and 6moPFS) with overall survival (OS), remains unknown. The quality of efficacy and toxicity reporting in these studies is also uncertain. A systematic review of systemic therapy RCTs in STS was performed. Surrogacy between intermediate end points and OS was explored using weighted linear regression for the hazard ratio for OS with the hazard ratio for PFS or the odds ratio for RR, 3moPFS, and 6moPFS. The quality of reporting for efficacy and toxicity was also evaluated. Fifty-two RCTs published between 1974 and 2014, comprising 9,762 patients, met the inclusion criteria. There were significant correlations between PFS and OS (R = 0.61) and between RR and OS (R = 0.51). Conversely, there were nonsignificant correlations between 3moPFS and 6moPFS with OS. A reduction in the use of RR as the primary end point was observed over time, favoring time-based events (P for trend = .02). In 14% of RCTs, the primary end point was not met, but the study was reported as being positive. Toxicity was comprehensively reported in 47% of RCTs, whereas 14% inadequately reported toxicity. In advanced STS, PFS and RR seem to be appropriate surrogates for OS. There is poor correlation between OS and both 3moPFS and 6moPFS. As such, caution is urged with the use of these as primary end points in randomized STS trials. The quality of toxicity reporting and interpretation of results is suboptimal. © 2016 by American Society of Clinical Oncology.

  19. Cohort profile

    DEFF Research Database (Denmark)

    Kreiberg, Michael; Bandak, Mikkel; Lauritsen, Jakob

    2018-01-01

    The cohort was set up in order to analyze late effects in long-term testicular cancer survivors (TCS) and to contribute to the design of future follow-up programs addressing and potentially preventing late effects. Data for this cross-sectional study were collected between January 1, 2014, and De...

  20. Selected ABCB1, ABCB4 and ABCC2 Polymorphisms Do Not Enhance the Risk of Drug-Induced Hepatotoxicity in a Spanish Cohort

    OpenAIRE

    Ulzurrun, Eugenia; Stephens, Camilla; Ruiz-Cabello, Francisco; Robles-Diaz, Mercedes; Saenz-López, Pablo; Hallal, Hacibe; Soriano, German; Roman, Eva; Fernandez, M. Carmen; Lucena, M. Isabel; Andrade, Raúl J.

    2014-01-01

    [Background and Aims] Flawed ABC transporter functions may contribute to increased risk of drug-induced liver injury (DILI). We aimed to analyse the influence of genetic variations in ABC transporters on the risk of DILI development and clinical presentations in a large Spanish DILI cohort. [Methods] A total of ten polymorphisms in ABCB1 (1236T>C, 2677G>T,A, 3435T>C), ABCB4 (1954A>G) and ABCC2 (???1774G>del, ???1549A>G, ???24C>T, 1249G>A, 3972C>T and 4544G>A) were genotyped using T...

  1. Organic Ferroelectric-Based 1T1T Random Access Memory Cell Employing a Common Dielectric Layer Overcoming the Half-Selection Problem.

    Science.gov (United States)

    Zhao, Qiang; Wang, Hanlin; Ni, Zhenjie; Liu, Jie; Zhen, Yonggang; Zhang, Xiaotao; Jiang, Lang; Li, Rongjin; Dong, Huanli; Hu, Wenping

    2017-09-01

    Organic electronics based on poly(vinylidenefluoride/trifluoroethylene) (P(VDF-TrFE)) dielectric is facing great challenges in flexible circuits. As one indispensable part of integrated circuits, there is an urgent demand for low-cost and easy-fabrication nonvolatile memory devices. A breakthrough is made on a novel ferroelectric random access memory cell (1T1T FeRAM cell) consisting of one selection transistor and one ferroelectric memory transistor in order to overcome the half-selection problem. Unlike complicated manufacturing using multiple dielectrics, this system simplifies 1T1T FeRAM cell fabrication using one common dielectric. To achieve this goal, a strategy for semiconductor/insulator (S/I) interface modulation is put forward and applied to nonhysteretic selection transistors with high performances for driving or addressing purposes. As a result, high hole mobility of 3.81 cm 2 V -1 s -1 (average) for 2,6-diphenylanthracene (DPA) and electron mobility of 0.124 cm 2 V -1 s -1 (average) for N,N'-1H,1H-perfluorobutyl dicyanoperylenecarboxydiimide (PDI-FCN 2 ) are obtained in selection transistors. In this work, we demonstrate this technology's potential for organic ferroelectric-based pixelated memory module fabrication. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Varying levels of difficulty index of skills-test items randomly selected by examinees on the Korean emergency medical technician licensing examination

    Directory of Open Access Journals (Sweden)

    Bongyeun Koh

    2016-01-01

    Full Text Available Purpose: The goal of this study was to characterize the difficulty index of the items in the skills test components of the class I and II Korean emergency medical technician licensing examination (KEMTLE, which requires examinees to select items randomly. Methods: The results of 1,309 class I KEMTLE examinations and 1,801 class II KEMTLE examinations in 2013 were subjected to analysis. Items from the basic and advanced skills test sections of the KEMTLE were compared to determine whether some were significantly more difficult than others. Results: In the class I KEMTLE, all 4 of the items on the basic skills test showed significant variation in difficulty index (P<0.01, as well as 4 of the 5 items on the advanced skills test (P<0.05. In the class II KEMTLE, 4 of the 5 items on the basic skills test showed significantly different difficulty index (P<0.01, as well as all 3 of the advanced skills test items (P<0.01. Conclusion: In the skills test components of the class I and II KEMTLE, the procedure in which examinees randomly select questions should be revised to require examinees to respond to a set of fixed items in order to improve the reliability of the national licensing examination.

  3. Varying levels of difficulty index of skills-test items randomly selected by examinees on the Korean emergency medical technician licensing examination.

    Science.gov (United States)

    Koh, Bongyeun; Hong, Sunggi; Kim, Soon-Sim; Hyun, Jin-Sook; Baek, Milye; Moon, Jundong; Kwon, Hayran; Kim, Gyoungyong; Min, Seonggi; Kang, Gu-Hyun

    2016-01-01

    The goal of this study was to characterize the difficulty index of the items in the skills test components of the class I and II Korean emergency medical technician licensing examination (KEMTLE), which requires examinees to select items randomly. The results of 1,309 class I KEMTLE examinations and 1,801 class II KEMTLE examinations in 2013 were subjected to analysis. Items from the basic and advanced skills test sections of the KEMTLE were compared to determine whether some were significantly more difficult than others. In the class I KEMTLE, all 4 of the items on the basic skills test showed significant variation in difficulty index (P<0.01), as well as 4 of the 5 items on the advanced skills test (P<0.05). In the class II KEMTLE, 4 of the 5 items on the basic skills test showed significantly different difficulty index (P<0.01), as well as all 3 of the advanced skills test items (P<0.01). In the skills test components of the class I and II KEMTLE, the procedure in which examinees randomly select questions should be revised to require examinees to respond to a set of fixed items in order to improve the reliability of the national licensing examination.

  4. Effects of choice architecture and chef-enhanced meals on the selection and consumption of healthier school foods: a randomized clinical trial.

    Science.gov (United States)

    Cohen, Juliana F W; Richardson, Scott A; Cluggish, Sarah A; Parker, Ellen; Catalano, Paul J; Rimm, Eric B

    2015-05-01

    Little is known about the long-term effect of a chef-enhanced menu on healthier food selection and consumption in school lunchrooms. In addition, it remains unclear if extended exposure to other strategies to promote healthier foods (eg, choice architecture) also improves food selection or consumption. To evaluate the short- and long-term effects of chef-enhanced meals and extended exposure to choice architecture on healthier school food selection and consumption. A school-based randomized clinical trial was conducted during the 2011-2012 school year among 14 elementary and middle schools in 2 urban, low-income school districts (intent-to-treat analysis). Included in the study were 2638 students in grades 3 through 8 attending participating schools (38.4% of eligible participants). Schools were first randomized to receive a professional chef to improve school meal palatability (chef schools) or to a delayed intervention (control group). To assess the effect of choice architecture (smart café), all schools after 3 months were then randomized to the smart café intervention or to the control group. School food selection was recorded, and consumption was measured using plate waste methods. After 3 months, vegetable selection increased in chef vs control schools (odds ratio [OR], 1.75; 95% CI, 1.36-2.24), but there was no effect on the selection of other components or on meal consumption. After long-term or extended exposure to the chef or smart café intervention, fruit selection increased in the chef (OR, 3.08; 95% CI, 2.23-4.25), smart café (OR, 1.45; 95% CI, 1.13-1.87), and chef plus smart café (OR, 3.10; 95% CI, 2.26-4.25) schools compared with the control schools, and consumption increased in the chef schools (OR, 0.17; 95% CI, 0.03-0.30 cups/d). Vegetable selection increased in the chef (OR, 2.54; 95% CI, 1.83-3.54), smart café (OR, 1.91; 95% CI, 1.46-2.50), and chef plus smart café schools (OR, 7.38, 95% CI, 5.26-10.35) compared with the control schools

  5. A randomized trial on mineralocorticoid receptor blockade in men: effects on stress responses, selective attention, and memory.

    Science.gov (United States)

    Cornelisse, Sandra; Joëls, Marian; Smeets, Tom

    2011-12-01

    Corticosteroids, released in high amounts after stress, exert their effects via two different receptors in the brain: glucocorticoid receptors (GRs) and mineralocorticoid receptors (MRs). GRs have a role in normalizing stress-induced effects and promoting consolidation, while MRs are thought to be important in determining the threshold for activation of the hypothalamic-pituitary-adrenal (HPA) axis. We investigated the effects of MR blockade on HPA axis responses to stress and stress-induced changes in cognitive function. In a double-blind, placebo-controlled study, 64 healthy young men received 400 mg of the MR antagonist spironolactone or placebo. After 1.5 h, they were exposed to either a Trier Social Stress Test or a non-stressful control task. Responses to stress were evaluated by hormonal, subjective, and physiological measurements. Afterwards, selective attention, working memory, and long-term memory performance were assessed. Spironolactone increased basal salivary cortisol levels as well as cortisol levels in response to stress. Furthermore, spironolactone significantly impaired selective attention, but only in the control group. The stress group receiving spironolactone showed impaired working memory performance. By contrast, long-term memory was enhanced in this group. These data support a role of MRs in the regulation of the HPA axis under basal conditions as well as in response to stress. The increased availability of cortisol after spironolactone treatment implies enhanced GR activation, which, in combination with MR blockade, presumably resulted in a decreased MR/GR activation ratio. This condition influences both selective attention and performance in various memory tasks.

  6. EcmPred: Prediction of extracellular matrix proteins based on random forest with maximum relevance minimum redundancy feature selection

    KAUST Repository

    Kandaswamy, Krishna Kumar Umar

    2013-01-01

    The extracellular matrix (ECM) is a major component of tissues of multicellular organisms. It consists of secreted macromolecules, mainly polysaccharides and glycoproteins. Malfunctions of ECM proteins lead to severe disorders such as marfan syndrome, osteogenesis imperfecta, numerous chondrodysplasias, and skin diseases. In this work, we report a random forest approach, EcmPred, for the prediction of ECM proteins from protein sequences. EcmPred was trained on a dataset containing 300 ECM and 300 non-ECM and tested on a dataset containing 145 ECM and 4187 non-ECM proteins. EcmPred achieved 83% accuracy on the training and 77% on the test dataset. EcmPred predicted 15 out of 20 experimentally verified ECM proteins. By scanning the entire human proteome, we predicted novel ECM proteins validated with gene ontology and InterPro. The dataset and standalone version of the EcmPred software is available at http://www.inb.uni-luebeck.de/tools-demos/Extracellular_matrix_proteins/EcmPred. © 2012 Elsevier Ltd.

  7. Food pantry selection solutions: a randomized controlled trial in client-choice food pantries to nudge clients to targeted foods.

    Science.gov (United States)

    Wilson, Norbert L W; Just, David R; Swigert, Jeffery; Wansink, Brian

    2017-06-01

    Food pantries and food banks are interested in cost-effective methods to encourage the selection of targeted foods without restricting choices. Thus, this study evaluates the effectiveness of nudges toward targeted foods. In October/November 2014, we manipulated the display of a targeted product in a New York State food pantry. We evaluated the binary choice of the targeted good when we placed it in the front or the back of the category line (placement order) and when we presented the product in its original box or unboxed (packaging). The average uptake proportion for the back treatment was 0.231, 95% CI = 0.179, 0.29, n = 205, and for the front treatment, the proportion was 0.337, 95% CI = 0.272, 0.406, n = 238 with an odds ratio of 1.688, 95% CI = 1.088, 2.523. The average uptake for the unboxed treatment was 0.224, 95% CI = 0.174, 0.280, n = 255, and for the boxed intervention, the proportion was 0.356, 95% CI = 0.288, 0.429, n = 188 with an odds ratio of 1.923, 95% CI = 1.237, 2.991. Nudges increased uptake of the targeted food. The findings also hold when we control for a potential confounder. Low cost and unobtrusive nudges can be effective tools for food pantry organizers to encourage the selection of targeted foods. NCT02403882. © The Author 2016. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. Recruitment strategies should not be randomly selected: empirically improving recruitment success and diversity in developmental psychology research

    Science.gov (United States)

    Sugden, Nicole A.; Moulson, Margaret C.

    2015-01-01

    Psychological and developmental research have been critiqued for the lack of diversity of research samples. Because differences in culture, race, and ethnicity can influence participant behavior, limited diversity limits the generalizability of the findings. These differences may also impact how participants behave in response to recruitment attempts, which suggests that recruitment itself may be leveraged to increase sample diversity. The goal of the current study was to determine what factors, within a recruitment interaction, could be leveraged to increase success and diversity when recruiting families with children for developmental research. Study 1 found three factors influenced success: (1) recruitment was more successful when other potential participants were also interested (i.e., recruiters were busy), (2) recruiters of particular races were more successful than recruiters of other races, and (3) differences in success were related to what the recruiter said to engage the potential participant (i.e., the script). The latter two factors interacted, suggesting some recruiters were using less optimal scripts. To improve success rates, study 2 randomly assigned scripts to recruiters and encouraged them to recruit more vigorously during busy periods. Study 2 found that two factors influenced success: (1) some scripts were more successful than others and (2) we were more successful at recruiting non-White potential participants than White participants. These two interacted, with some scripts being more successful with White and other scripts being more successful with non-White families. This intervention significantly increased recruitment success rate by 8.1% and the overall number of families recruited by 15.3%. These findings reveal that empirically evaluating and tailoring recruitment efforts based on the most successful strategies is effective in boosting diversity through increased participation of children from non-White families. PMID:25972829

  9. Suicide in Nepal: a modified psychological autopsy investigation from randomly selected police cases between 2013 and 2015.

    Science.gov (United States)

    Hagaman, Ashley K; Khadka, S; Lohani, S; Kohrt, B

    2017-12-01

    Yearly, 600,000 people complete suicide in low- and middle-income countries, accounting for 75% of the world's burden of suicide mortality. The highest regional rates are in South and East Asia. Nepal has one of the highest suicide rates in the world; however, few investigations exploring patterns surrounding both male and female suicides exist. This study used psychological autopsies to identify common factors, precipitating events, and warning signs in a diverse sample. Randomly sampled from 302 police case reports over 24 months, psychological autopsies were conducted for 39 completed suicide cases in one urban and one rural region of Nepal. In the total police sample (n = 302), 57.0% of deaths were male. Over 40% of deaths were 25 years or younger, including 65% of rural and 50.8% of female suicide deaths. We estimate the crude urban and rural suicide rates to be 16.1 and 22.8 per 100,000, respectively. Within our psychological autopsy sample, 38.5% met criteria for depression and only 23.1% informants believed that the deceased had thoughts of self-harm or suicide before death. Important warning signs include recent geographic migration, alcohol abuse, and family history of suicide. Suicide prevention strategies in Nepal should account for the lack of awareness about suicide risk among family members and early age of suicide completion, especially in rural and female populations. Given the low rates of ideation disclosure to friends and family, educating the general public about other signs of suicide may help prevention efforts in Nepal.

  10. Risk of infection and adverse outcomes among pregnant working women in selected occupational groups: A study in the Danish National Birth Cohort

    Directory of Open Access Journals (Sweden)

    Llopis-González Agustín

    2010-11-01

    Full Text Available Abstract Background Exposure to infectious pathogens is a frequent occupational hazard for women who work with patients, children, animals or animal products. The purpose of the present study is to investigate if women working in occupations where exposure to infections agents is common have a high risk of infections and adverse pregnancy outcomes. Methods We used data from the Danish National Birth Cohort, a population-based cohort study and studied the risk of Infection and adverse outcomes in pregnant women working with patients, with children, with food products or with animals. The regression analysis were adjusted for the following covariates: maternal age, parity, history of miscarriage, socio-occupational status, pre-pregnancy body mass index, smoking habit, alcohol consumption. Results Pregnant women who worked with patients or children or food products had an excess risk of sick leave during pregnancy for more than three days. Most of negative reproductive outcomes were not increased in these occupations but the prevalence of congenital anomalies (CAs was slightly higher in children of women who worked with patients. The prevalence of small for gestational age infants was higher among women who worked with food products. There was no association between occupation infections during pregnancy and the risk of reproductive failures in the exposed groups. However, the prevalence of CAs was slightly higher among children of women who suffered some infection during pregnancy but the numbers were small. Conclusion Despite preventive strategies, working in specific jobs during pregnancy may impose a higher risk of infections, and working in some of these occupations may impose a slightly higher risk of CAs in their offspring. Most other reproductive failures were not increased in these occupations.

  11. Selection of drug resistant mutants from random library of Plasmodium falciparum dihydrofolate reductase in Plasmodium berghei model

    Directory of Open Access Journals (Sweden)

    Yuthavong Yongyuth

    2011-05-01

    Full Text Available Abstract Background The prevalence of drug resistance amongst the human malaria Plasmodium species has most commonly been associated with genomic mutation within the parasites. This phenomenon necessitates evolutionary predictive studies of possible resistance mutations, which may occur when a new drug is introduced. Therefore, identification of possible new Plasmodium falciparum dihydrofolate reductase (PfDHFR mutants that confer resistance to antifolate drugs is essential in the process of antifolate anti-malarial drug development. Methods A system to identify mutations in Pfdhfr gene that confer antifolate drug resistance using an animal Plasmodium parasite model was developed. By using error-prone PCR and Plasmodium transfection technologies, libraries of Pfdhfr mutant were generated and then episomally transfected to Plasmodium berghei parasites, from which pyrimethamine-resistant PfDHFR mutants were selected. Results The principal mutation found from this experiment was S108N, coincident with the first pyrimethamine-resistance mutation isolated from the field. A transgenic P. berghei, in which endogenous Pbdhfr allele was replaced with the mutant PfdhfrS108N, was generated and confirmed to have normal growth rate comparing to parental non-transgenic parasite and also confer resistance to pyrimethamine. Conclusion This study demonstrated the power of the transgenic P. berghei system to predict drug-resistant Pfdhfr mutations in an in vivo parasite/host setting. The system could be utilized for identification of possible novel drug-resistant mutants that could arise against new antifolate compounds and for prediction the evolution of resistance mutations.

  12. Managing salinity in Upper Colorado River Basin streams: Selecting catchments for sediment control efforts using watershed characteristics and random forests models

    Science.gov (United States)

    Tillman, Fred; Anning, David W.; Heilman, Julian A.; Buto, Susan G.; Miller, Matthew P.

    2018-01-01

    Elevated concentrations of dissolved-solids (salinity) including calcium, sodium, sulfate, and chloride, among others, in the Colorado River cause substantial problems for its water users. Previous efforts to reduce dissolved solids in upper Colorado River basin (UCRB) streams often focused on reducing suspended-sediment transport to streams, but few studies have investigated the relationship between suspended sediment and salinity, or evaluated which watershed characteristics might be associated with this relationship. Are there catchment properties that may help in identifying areas where control of suspended sediment will also reduce salinity transport to streams? A random forests classification analysis was performed on topographic, climate, land cover, geology, rock chemistry, soil, and hydrologic information in 163 UCRB catchments. Two random forests models were developed in this study: one for exploring stream and catchment characteristics associated with stream sites where dissolved solids increase with increasing suspended-sediment concentration, and the other for predicting where these sites are located in unmonitored reaches. Results of variable importance from the exploratory random forests models indicate that no simple source, geochemical process, or transport mechanism can easily explain the relationship between dissolved solids and suspended sediment concentrations at UCRB monitoring sites. Among the most important watershed characteristics in both models were measures of soil hydraulic conductivity, soil erodibility, minimum catchment elevation, catchment area, and the silt component of soil in the catchment. Predictions at key locations in the basin were combined with observations from selected monitoring sites, and presented in map-form to give a complete understanding of where catchment sediment control practices would also benefit control of dissolved solids in streams.

  13. Effect of a Counseling Session Bolstered by Text Messaging on Self-Selected Health Behaviors in College Students: A Preliminary Randomized Controlled Trial.

    Science.gov (United States)

    Sandrick, Janice; Tracy, Doreen; Eliasson, Arn; Roth, Ashley; Bartel, Jeffrey; Simko, Melanie; Bowman, Tracy; Harouse-Bell, Karen; Kashani, Mariam; Vernalis, Marina

    2017-05-17

    The college experience is often the first time when young adults live independently and make their own lifestyle choices. These choices affect dietary behaviors, exercise habits, techniques to deal with stress, and decisions on sleep time, all of which direct the trajectory of future health. There is a need for effective strategies that will encourage healthy lifestyle choices in young adults attending college. This preliminary randomized controlled trial tested the effect of coaching and text messages (short message service, SMS) on self-selected health behaviors in the domains of diet, exercise, stress, and sleep. A second analysis measured the ripple effect of the intervention on health behaviors not specifically selected as a goal by participants. Full-time students aged 18-30 years were recruited by word of mouth and campuswide advertisements (flyers, posters, mailings, university website) at a small university in western Pennsylvania from January to May 2015. Exclusions included pregnancy, eating disorders, chronic medical diagnoses, and prescription medications other than birth control. Of 60 participants, 30 were randomized to receive a single face-to-face meeting with a health coach to review results of behavioral questionnaires and to set a health behavior goal for the 8-week study period. The face-to-face meeting was followed by SMS text messages designed to encourage achievement of the behavioral goal. A total of 30 control subjects underwent the same health and behavioral assessments at intake and program end but did not receive coaching or SMS text messages. The texting app showed that 87.31% (2187/2505) of messages were viewed by intervention participants. Furthermore, 28 of the 30 intervention participants and all 30 control participants provided outcome data. Among intervention participants, 22 of 30 (73%) showed improvement in health behavior goal attainment, with the whole group (n=30) showing a mean improvement of 88% (95% CI 39-136). Mean

  14. A theory for the origin of a self-replicating chemical system. I - Natural selection of the autogen from short, random oligomers

    Science.gov (United States)

    White, D. H.

    1980-01-01

    A general theory is presented for the origin of a self-replicating chemical system, termed an autogen, which is capable of both crude replication and translation (protein synthesis). The theory requires the availability of free energy and monomers to the system, a significant background low-yield synthesis of kinetically stable oligopeptides and oligonucleotides, the localization of the oligomers, crude oligonucleotide selectivity of amino acids during oligopeptide synthesis, crude oligonucleotide replication, and two short peptide families which catalyze replication and translation, to produce a localized group of at least one copy each of two protogenes and two protoenzymes. The model posits a process of random oligomerization, followed by the random nucleation of functional components and the rapid autocatalytic growth of the functioning autogen to macroscopic amounts, to account for the origin of the first self-replicating system. Such a process contains steps of such high probability and short time periods that it is suggested that the emergence of an autogen in a laboratory experiment of reasonable time scale may be possible.

  15. Effects of Video Game Training on Measures of Selective Attention and Working Memory in Older Adults: Results from a Randomized Controlled Trial

    Science.gov (United States)

    Ballesteros, Soledad; Mayas, Julia; Prieto, Antonio; Ruiz-Marquez, Eloísa; Toril, Pilar; Reales, José M.

    2017-01-01

    Video game training with older adults potentially enhances aspects of cognition that decline with aging and could therefore offer a promising training approach. Although, previous published studies suggest that training can produce transfer, many of them have certain shortcomings. This randomized controlled trial (RCT; Clinicaltrials.gov ID: NCT02796508) tried to overcome some of these limitations by incorporating an active control group and the assessment of motivation and expectations. Seventy-five older volunteers were randomly assigned to the experimental group trained for 16 sessions with non-action video games from Lumosity, a commercial platform (http://www.lumosity.com/) or to an active control group trained for the same number of sessions with simulation strategy games. The final sample included 55 older adults (30 in the experimental group and 25 in the active control group). Participants were tested individually before and after training to assess working memory (WM) and selective attention and also reported their perceived improvement, motivation and engagement. The results showed improved performance across the training sessions. The main results were: (1) the experimental group did not show greater improvements in measures of selective attention and working memory than the active control group (the opposite occurred in the oddball task); (2) a marginal training effect was observed for the N-back task, but not for the Stroop task while both groups improved in the Corsi Blocks task. Based on these results, one can conclude that training with non-action games provide modest benefits for untrained tasks. The effect is not specific for that kind of training as a similar effect was observed for strategy video games. Groups did not differ in motivation, engagement or expectations. PMID:29163136

  16. Effects of Video Game Training on Measures of Selective Attention and Working Memory in Older Adults: Results from a Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Soledad Ballesteros

    2017-11-01

    Full Text Available Video game training with older adults potentially enhances aspects of cognition that decline with aging and could therefore offer a promising training approach. Although, previous published studies suggest that training can produce transfer, many of them have certain shortcomings. This randomized controlled trial (RCT; Clinicaltrials.gov ID: NCT02796508 tried to overcome some of these limitations by incorporating an active control group and the assessment of motivation and expectations. Seventy-five older volunteers were randomly assigned to the experimental group trained for 16 sessions with non-action video games from Lumosity, a commercial platform (http://www.lumosity.com/ or to an active control group trained for the same number of sessions with simulation strategy games. The final sample included 55 older adults (30 in the experimental group and 25 in the active control group. Participants were tested individually before and after training to assess working memory (WM and selective attention and also reported their perceived improvement, motivation and engagement. The results showed improved performance across the training sessions. The main results were: (1 the experimental group did not show greater improvements in measures of selective attention and working memory than the active control group (the opposite occurred in the oddball task; (2 a marginal training effect was observed for the N-back task, but not for the Stroop task while both groups improved in the Corsi Blocks task. Based on these results, one can conclude that training with non-action games provide modest benefits for untrained tasks. The effect is not specific for that kind of training as a similar effect was observed for strategy video games. Groups did not differ in motivation, engagement or expectations.

  17. Effects of Video Game Training on Measures of Selective Attention and Working Memory in Older Adults: Results from a Randomized Controlled Trial.

    Science.gov (United States)

    Ballesteros, Soledad; Mayas, Julia; Prieto, Antonio; Ruiz-Marquez, Eloísa; Toril, Pilar; Reales, José M

    2017-01-01

    Video game training with older adults potentially enhances aspects of cognition that decline with aging and could therefore offer a promising training approach. Although, previous published studies suggest that training can produce transfer, many of them have certain shortcomings. This randomized controlled trial (RCT; Clinicaltrials.gov ID: NCT02796508) tried to overcome some of these limitations by incorporating an active control group and the assessment of motivation and expectations. Seventy-five older volunteers were randomly assigned to the experimental group trained for 16 sessions with non-action video games from Lumosity , a commercial platform (http://www.lumosity.com/) or to an active control group trained for the same number of sessions with simulation strategy games. The final sample included 55 older adults (30 in the experimental group and 25 in the active control group). Participants were tested individually before and after training to assess working memory (WM) and selective attention and also reported their perceived improvement, motivation and engagement. The results showed improved performance across the training sessions. The main results were: (1) the experimental group did not show greater improvements in measures of selective attention and working memory than the active control group (the opposite occurred in the oddball task); (2) a marginal training effect was observed for the N -back task, but not for the Stroop task while both groups improved in the Corsi Blocks task. Based on these results, one can conclude that training with non-action games provide modest benefits for untrained tasks. The effect is not specific for that kind of training as a similar effect was observed for strategy video games. Groups did not differ in motivation, engagement or expectations.

  18. A patient and community-centered approach selecting endpoints for a randomized trial of a novel advance care planning tool

    Directory of Open Access Journals (Sweden)

    Bridges JFP

    2018-02-01

    Full Text Available John FP Bridges,1,2 Norah L Crossnohere,2 Anne L Schuster,1 Judith A Miller,3 Carolyn Pastorini,3,† Rebecca A Aslakson2,4,5 1Department of Health Policy and Management, The Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 2Department of Health, Behavior, and Society, The Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 3Patient-Centered Outcomes Research Institute (PCORI Project, Baltimore, MD, 4Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins School of Medicine, Baltimore, MD, 5Armstrong Institute for Patient Safety and Quality, The Johns Hopkins School of Medicine, Baltimore, MD, USA †Carolyn Pastorini passed away on August 24, 2015 Background: Despite a movement toward patient-centered outcomes, best practices on how to gather and refine patients’ perspectives on research endpoints are limited. Advanced care planning (ACP is inherently patient centered and would benefit from patient prioritization of endpoints for ACP-related tools and studies.Objective: This investigation sought to prioritize patient-centered endpoints for the content and evaluation of an ACP video being developed for patients undergoing major surgery. We also sought to highlight an approach using complementary engagement and research strategies to document priorities and preferences of patients and other stakeholders.Materials and methods: Endpoints identified from a previously published environmental scan were operationalized following rating by a caregiver co-investigator, refinement by a patient co-investigator, review by a stakeholder committee, and validation by patients and family members. Finalized endpoints were taken to a state fair where members of the public who indicated that they or a loved one had undergone major surgery prioritized their most relevant endpoints and provided comments.Results: Of the initial 50 ACP endpoints identified from the review, 12 endpoints were selected for public

  19. A randomized controlled trial investigating the use of a predictive nomogram for the selection of the FSH starting dose in IVF/ICSI cycles.

    Science.gov (United States)

    Allegra, Adolfo; Marino, Angelo; Volpes, Aldo; Coffaro, Francesco; Scaglione, Piero; Gullo, Salvatore; La Marca, Antonio

    2017-04-01

    The number of oocytes retrieved is a relevant intermediate outcome in women undergoing IVF/intracytoplasmic sperm injection (ICSI). This trial compared the efficiency of the selection of the FSH starting dose according to a nomogram based on multiple biomarkers (age, day 3 FSH, anti-Müllerian hormone) versus an age-based strategy. The primary outcome measure was the proportion of women with an optimal number of retrieved oocytes defined as 8-14. At their first IVF/ICSI cycle, 191 patients underwent a long gonadotrophin-releasing hormone agonist protocol and were randomized to receive a starting dose of recombinant (human) FSH, based on their age (150 IU if ≤35 years, 225 IU if >35 years) or based on the nomogram. Optimal response was observed in 58/92 patients (63%) in the nomogram group and in 42/99 (42%) in the control group (+21%, 95% CI = 0.07 to 0.35, P = 0.0037). No significant differences were found in the clinical pregnancy rate or the number of embryos cryopreserved per patient. The study showed that the FSH starting dose selected according to ovarian reserve is associated with an increase in the proportion of patients with an optimal response: large trials are recommended to investigate any possible effect on the live-birth rate. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  20. Novel β-lactamase-random peptide fusion libraries for phage display selection of cancer cell-targeting agents suitable for enzyme prodrug therapy

    Science.gov (United States)

    Shukla, Girja S.; Krag, David N.

    2010-01-01

    Novel phage-displayed random linear dodecapeptide (X12) and cysteine-constrained decapeptide (CX10C) libraries constructed in fusion to the amino-terminus of P99 β-lactamase molecules were used for identifying β-lactamase-linked cancer cell-specific ligands. The size and quality of both libraries were comparable to the standards of other reported phage display systems. Using the single-round panning method based on phage DNA recovery, we identified severalβ-lactamase fusion peptides that specifically bind to live human breast cancer MDA-MB-361 cells. The β-lactamase fusion to the peptides helped in conducting the enzyme activity-based clone normalization and cell-binding screening in a very time- and cost-efficient manner. The methods were suitable for 96-well readout as well as microscopic imaging. The success of the biopanning was indicated by the presence of ~40% cancer cell-specific clones among recovered phages. One of the binding clones appeared multiple times. The cancer cell-binding fusion peptides also shared several significant motifs. This opens a new way of preparing and selecting phage display libraries. The cancer cell-specific β-lactamase-linked affinity reagents selected from these libraries can be used for any application that requires a reporter for tracking the ligand molecules. Furthermore, these affinity reagents have also a potential for their direct use in the targeted enzyme prodrug therapy of cancer. PMID:19751096

  1. Mucositis reduction by selective elimination of oral flora in irradiated cancers of the head and neck: a placebo-controlled double-blind randomized study

    International Nuclear Information System (INIS)

    Wijers, Oda B.; Levendag, Peter C.; Harms, Erik; Gan-Teng, A.M.; Schmitz, Paul I.M.; Hendriks, W.D.H.; Wilms, Erik B.; Est, Henri van der; Visch, Leo L.

    2001-01-01

    Purpose: The aim of the study was to test the hypothesis that aerobic Gram-negative bacteria (AGNB) play a crucial role in the pathogenesis of radiation-induced mucositis; consequently, selective elimination of these bacteria from the oral flora should result in a reduction of the mucositis. Methods and Materials: Head-and-neck cancer patients, when scheduled for treatment by external beam radiation therapy (EBRT), were randomized for prophylactic treatment with an oral paste containing either a placebo or a combination of the antibiotics polymyxin E, tobramycin, and amphotericin B (PTA group). Weekly, the objective and subjective mucositis scores and microbiologic counts of the oral flora were noted. The primary study endpoint was the mucositis grade after 3 weeks of EBRT. Results: Seventy-seven patients were evaluable. No statistically significant difference for the objective and subjective mucositis scores was observed between the two study arms (p=0.33). The percentage of patients with positive cultures of AGNB was significantly reduced in the PTA group (p=0.01). However, complete eradication of AGNB was not achieved. Conclusions: Selective elimination of AGNB of the oral flora did not result in a reduction of radiation-induced mucositis and therefore does not support the hypothesis that these bacteria play a crucial role in the pathogenesis of mucositis

  2. Arthroscopic Surgical Procedures Versus Sham Surgery for Patients With Femoroacetabular Impingement and/or Labral Tears: Study Protocol for a Randomized Controlled Trial (HIPARTI) and a Prospective Cohort Study (HARP).

    Science.gov (United States)

    Risberg, May Arna; Ageberg, Eva; Nilstad, Agnethe; Lund, Bent; Nordsletten, Lars; Løken, Sverre; Ludvigsen, Tom; Kierkegaard, Signe; Carsen, Sasha; Kostogiannis, Ioannis; Crossley, Kay M; Glyn-Jones, Sion; Kemp, Joanne L

    2018-04-01

    Study Design Study protocol for a randomized controlled trial and a prospective cohort. Background The number of arthroscopic surgical procedures for patients with femoroacetabular impingement syndrome (FAIS) has significantly increased worldwide, but high-quality evidence of the effect of such interventions is lacking. Objectives The primary objective will be to determine the efficacy of hip arthroscopic procedures compared to sham surgery on patient-reported outcomes for patients with FAIS (HIP ARThroscopy International [HIPARTI] Study). The secondary objective will be to evaluate prognostic factors for long-term outcome after arthroscopic surgical interventions in patients with FAIS (Hip ARthroscopy Prospective [HARP] Study). Methods The HIPARTI Study will include 140 patients and the HARP Study will include 100 patients. The international Hip Outcome Tool-33 will be the primary outcome measure at 1 year. Secondary outcome measures will be the Hip disability and Osteoarthritis Outcome Score, Arthritis Self-Efficacy Scale, fear of movement (Tampa Scale of Kinesiophobia), Patient-Specific Functional Scale, global rating of change score, and expectations. Other outcomes will include active hip range of motion, hip muscle strength tests, functional performance tests, as well as radiological assessments using radiographs and magnetic resonance imaging. Conclusion To determine the true effect of surgery, beyond that of placebo, double-blinded placebo-controlled trials including sham surgery are needed. The HIPARTI Study will direct future evidence-based treatment of FAIS. Predictors for long-term development and progression of degenerative changes in the hip are also needed for this young patient group with FAIS; hence, responders and nonresponders to treatment could be determined. J Orthop Sports Phys Ther 2018;48(4):325-335. doi:10.2519/jospt.2018.7931.

  3. Treatment of pregnancy-related pelvic girdle and/or low back pain after delivery design of a randomized clinical trial within a comprehensive prognostic cohort study [ISRCTN08477490

    Directory of Open Access Journals (Sweden)

    Klabbers Aldegonda BA

    2004-12-01

    Full Text Available Abstract Background Pregnancy-related pelvic girdle and/or low back pain is a controversial syndrome because insight in etiology and prognosis is lacking. The controversy relates to factors eliciting pain and some prognostic factors such as the interpretation of pain at the symphysis. Recent research about treatment strategies also reflects those various opinions, in fact suggesting there is professional uncertainty about the optimal approach. Currently, physiotherapists often prescribe a pain-contingent treatment regime of relative rest and avoiding several day-to-day activities. Additionally, treatment more often includes an exercise program to guide rectification of the muscle imbalance and alignment of the pelvic girdle. Effectiveness of those interventions is not proven and the majority of the studies are methodologically flawed. Investigators draw particular attention to biomedical factors but there is growing evidence that important prognostic issues such as biopsychosocial factors appear to be even more important as point of action in a treatment program. Methods/design This pragmatic randomized controlled trial is designed to evaluate the effectiveness of a tailor-made treatment program with respect to biopsychosocial factors in primary care. The effect of the experimental intervention and usual care are evaluated as they are applied in primary health care. The trial is embedded in a cohort study that is designed as a longitudinal, prospective study, which studies prevalence, etiology, severity and prognosis during pregnancy until one year after delivery. The present paper focuses on choices regarding recruitment procedures, in-/exclusion criteria and the development of a well-timed intervention. Discussion This section briefly discusses the actions taken to minimize bias in the design, the proper time-window for the experimental intervention and the contrast between the experimental intervention and usual care.

  4. Prevalence of at-risk genotypes for genotoxic effects decreases with age in a randomly selected population in Flanders: a cross sectional study

    Directory of Open Access Journals (Sweden)

    van Delft Joost HM

    2011-10-01

    Full Text Available Abstract Background We hypothesized that in Flanders (Belgium, the prevalence of at-risk genotypes for genotoxic effects decreases with age due to morbidity and mortality resulting from chronic diseases. Rather than polymorphisms in single genes, the interaction of multiple genetic polymorphisms in low penetrance genes involved in genotoxic effects might be of relevance. Methods Genotyping was performed on 399 randomly selected adults (aged 50-65 and on 442 randomly selected adolescents. Based on their involvement in processes relevant to genotoxicity, 28 low penetrance polymorphisms affecting the phenotype in 19 genes were selected (xenobiotic metabolism, oxidative stress defense and DNA repair, respectively 13, 6 and 9 polymorphisms. Polymorphisms which, based on available literature, could not clearly be categorized a priori as leading to an 'increased risk' or a 'protective effect' were excluded. Results The mean number of risk alleles for all investigated polymorphisms was found to be lower in the 'elderly' (17.0 ± 2.9 than the 'adolescent' (17.6 ± 3.1 subpopulation (P = 0.002. These results were not affected by gender nor smoking. The prevalence of a high (> 17 = median number of risk alleles was less frequent in the 'elderly' (40.6% than the 'adolescent' (51.4% subpopulation (P = 0.002. In particular for phase II enzymes, the mean number of risk alleles was lower in the 'elderly' (4.3 ± 1.6 than the 'adolescent' age group (4.8 ± 1.9 P 4 = median number of risk alleles was less frequent in the 'elderly' (41.3% than the adolescent subpopulation (56.3%, P 8 = median number of risk alleles for DNA repair enzyme-coding genes was lower in the 'elderly' (37,3% than the 'adolescent' subpopulation (45.6%, P = 0.017. Conclusions These observations are consistent with the hypothesis that, in Flanders, the prevalence of at-risk alleles in genes involved in genotoxic effects decreases with age, suggesting that persons carrying a higher number of

  5. PONTIAC (NT-proBNP selected prevention of cardiac events in a population of diabetic patients without a history of cardiac disease): a prospective randomized controlled trial.

    Science.gov (United States)

    Huelsmann, Martin; Neuhold, Stephanie; Resl, Michael; Strunk, Guido; Brath, Helmut; Francesconi, Claudia; Adlbrecht, Christopher; Prager, Rudolf; Luger, Anton; Pacher, Richard; Clodi, Martin

    2013-10-08

    The study sought to assess the primary preventive effect of neurohumoral therapy in high-risk diabetic patients selected by N-terminal pro-B-type natriuretic peptide (NT-proBNP). Few clinical trials have successfully demonstrated the prevention of cardiac events in patients with diabetes. One reason for this might be an inaccurate selection of patients. NT-proBNP has not been assessed in this context. A total of 300 patients with type 2 diabetes, elevated NT-proBNP (>125 pg/ml) but free of cardiac disease were randomized. The "control" group was cared for at 4 diabetes care units; the "intensified" group was additionally treated at a cardiac outpatient clinic for the up-titration of renin-angiotensin system (RAS) antagonists and beta-blockers. The primary endpoint was hospitalization/death due to cardiac disease after 2 years. At baseline, the mean age of the patients was 67.5 ± 9 years, duration of diabetes was 15 ± 12 years, 37% were male, HbA1c was 7 ± 1.1%, blood pressure was 151 ± 22 mm Hg, heart rate was 72 ± 11 beats/min, median NT-proBNP was 265.5 pg/ml (interquartile range: 180.8 to 401.8 pg/ml). After 12 months there was a significant difference between the number of patients treated with a RAS antagonist/beta-blocker and the dosage reached between groups (p titration of RAS antagonists and beta-blockers to maximum tolerated dosages is an effective and safe intervention for the primary prevention of cardiac events for diabetic patients pre-selected using NT-proBNP. (Nt-proBNP Guided Primary Prevention of CV Events in Diabetic Patients [PONTIAC]; NCT00562952). Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  6. Cohort description

    DEFF Research Database (Denmark)

    Dantoft, Thomas Meinertz; Ebstrup, Jeanette Frost; Linneberg, Allan

    2017-01-01

    -76 years from the general population examined from 2011 to 2015. The survey comprises screening questionnaires for five types of FSS, ie, fibromyalgia, whiplash-associated disorder, multiple chemical sensitivity, irritable bowel syndrome, and chronic fatigue syndrome, and for the unifying diagnostic......The Danish study of Functional Disorders (DanFunD) cohort was initiated to outline the epidemiology of functional somatic syndromes (FSS) and is the first larger coordinated epidemiological study focusing exclusively on FSS. FSS are prevalent in all medical settings and can be defined as syndromes...... category of bodily distress syndrome. Additional data included a telephone-based diagnostic interview assessment for FSS, questionnaires on physical and mental health, personality traits, lifestyle, use of health care services and social factors, and a physical examination with measures...

  7. Investigation of selection bias in the association of race with prevalent atrial fibrillation in a national cohort study: REasons for Geographic And Racial Differences in Stroke (REGARDS).

    Science.gov (United States)

    Thacker, Evan L; Soliman, Elsayed Z; Pulley, LeaVonne; Safford, Monika M; Howard, George; Howard, Virginia J

    2016-08-01

    Atrial fibrillation (AF) is diagnosed more commonly in whites than blacks in the United States. In epidemiologic studies, selection bias could induce a noncausal positive association of white race with prevalent AF if voluntary enrollment was influenced by both race and AF status. We investigated whether nonrandom enrollment biased the association of race with prevalent self-reported AF in the US-based REasons for Geographic And Racial Differences in Stroke Study (REGARDS). REGARDS had a two-stage enrollment process, allowing us to compare 30,183 fully enrolled REGARDS participants with 12,828 people who completed the first-stage telephone survey but did not complete the second-stage in-home visit to finalize their REGARDS enrollment (telephone-only participants). REGARDS enrollment was higher among whites (77.1%) than among blacks (62.3%) but did not differ by self-reported AF status. The prevalence of AF was 8.45% in whites and 5.86% in blacks adjusted for age, sex, income, education, and perceived general health. The adjusted white/black prevalence ratio of self-reported AF was 1.43 (95% CI, 1.32-1.56) among REGARDS participants and 1.38 (1.22-1.55) among telephone-only participants. These findings suggest that selection bias is not a viable explanation for the higher prevalence of self-reported AF among whites in population studies such as REGARDS. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Common selective serotonin reuptake inhibitor side effects in older adults associated with genetic polymorphisms in the serotonin transporter and receptors: data from a randomized controlled trial.

    Science.gov (United States)

    Garfield, Lauren D; Dixon, David; Nowotny, Petra; Lotrich, Francis E; Pollock, Bruce G; Kristjansson, Sean D; Doré, Peter M; Lenze, Eric J

    2014-10-01

    Antidepressant side effects are a significant public health issue, associated with poor adherence, premature treatment discontinuation, and, rarely, significant harm. Older adults assume the largest and most serious burden of medication side effects. We investigated the association between antidepressant side effects and genetic variation in the serotonin system in anxious, older adults participating in a randomized, placebo-controlled trial of the selective serotonin reuptake inhibitor (SSRI) escitalopram. Adults (N = 177) aged ≥ 60 years were randomized to active treatment or placebo for 12 weeks. Side effects were assessed using the Udvalg fur Kliniske Undersøgelser side-effect rating scale. Genetic polymorphisms were putative functional variants in the promoters of the serotonin transporter and 1A and 2A receptors (5-HTTLPR [L/S + rs25531], HTR1A rs6295, HTR2A rs6311, respectively). Four significant drug-placebo side-effect differences were found: increased duration of sleep, dry mouth, diarrhea, and diminished sexual desire. Analyses using putative high- versus low-transcription genotype groupings revealed six pharmacogenetic effects: greater dry mouth and decreased sexual desire for the low- and high-expressing serotonin transporter genotypes, respectively, and greater diarrhea with the 1A receptor low-transcription genotype. Diminished sexual desire was experienced significantly more by high-expressing genotypes in the serotonin transporter, 1A, or 2A receptors. There was not a significant relationship between drug concentration and side effects nor a mean difference in drug concentration between low- and high-expressing genotypes. Genetic variation in the serotonin system may predict who develops common SSRI side effects and why. More work is needed to further characterize this genetic modulation and to translate research findings into strategies useful for more personalized patient care. Published by Elsevier Inc.

  9. CONSTANCES: a general prospective population-based cohort for occupational and environmental epidemiology: cohort profile.

    Science.gov (United States)

    Goldberg, Marcel; Carton, Matthieu; Descatha, Alexis; Leclerc, Annette; Roquelaure, Yves; Santin, Gaëlle; Zins, Marie

    2017-01-01

    WHY THE COHORT WAS SET UP?: CONSTANCES is a general-purpose cohort with a focus on occupational and environmental factors. CONSTANCES was designed as a randomly selected sample of French adults aged 18-69 years at inception; 200 000 participants will be included. At enrolment, the participants are invited to complete questionnaires and to attend a health screening centre (HSC) for a health examination. A biobank will be set up. The follow-up includes an yearly self-administered questionnaire, a periodic visit to an HSC and linkage to social and national health administrative databases. Data collected for participants include social and demographic characteristics, socioeconomic status, life events and behaviours. Regarding occupational and environmental factors, a wealth of data on organisational, chemical, biological, biomechanical and psychosocial lifelong exposure, as well as residential characteristics, are collected at enrolment and during follow-up. The health data cover a wide spectrum: self-reported health scales, reported prevalent and incident diseases, long-term chronic diseases and hospitalisations, sick-leaves, handicaps, limitations, disabilities and injuries, healthcare usage and services provided, and causes of death. To take into account non-participation and attrition, a random cohort of non-participants was set up and will be followed through the same national databases as participants. Inclusions begun at the end of 2012 and more than 110 000 participants were already included by September 2016. Several projects on occupational and environmental risks already applied to a public call for nested research projects. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  10. Maternal Use of Selective Serotonin Reuptake Inhibitors and Lengthening of the Umbilical Cord: Indirect Evidence of Increased Foetal Activity-A Retrospective Cohort Study.

    Directory of Open Access Journals (Sweden)

    Julia Kivistö

    Full Text Available Antenatal depression affects up to 19% of pregnant women. Some of these women are also in need of antidepressant treatment. Nevertheless, the impact of maternal antidepressant treatment and prenatal depression on the course of pregnancy, foetal development and delivery outcomes is not fully understood.We analysed data from 24 818 women who gave birth at Kuopio University Hospital between 2002-2012. Logistic regression analysis was used to estimate associations between the use of selective serotonin reuptake inhibitors (SSRIs during pregnancy and the progression of pregnancy, development of the foetus and delivery outcomes.Altogether, 369 (1.5% women used SSRIs. A regression model adjusted for age, overweight, nulliparity, prior termination, miscarriages, smoking, maternal alcohol consumption, chronic illness and polyhydramnion showed that pregnant women exposed to SSRI medication had significantly lower Apgar scores at 1 minute (p < 0.0001 and 5 minutes (p < 0.0001 and more admissions to the neonatal intensive care unit (p < 0.0001 than unexposed pregnant women. In addition, exposed newborns had longer umbilical cords (p < 0.0001 than non-exposed newborns.In addition to the previously known associates with maternal SSRI exposure, such as lowered Apgar scores, SSRI exposure appeared to be associated with increased umbilical cord length. The observation related to increased umbilical cord length may be explained by an SSRI-induced increase in the movements of the developing foetus.

  11. On the role of heat and mass transfer into laser processability during selective laser melting AlSi12 alloy based on a randomly packed powder-bed

    Science.gov (United States)

    Wang, Lianfeng; Yan, Biao; Guo, Lijie; Gu, Dongdong

    2018-04-01

    A newly transient mesoscopic model with a randomly packed powder-bed has been proposed to investigate the heat and mass transfer and laser process quality between neighboring tracks during selective laser melting (SLM) AlSi12 alloy by finite volume method (FVM), considering the solid/liquid phase transition, variable temperature-dependent properties and interfacial force. The results apparently revealed that both the operating temperature and resultant cooling rate were obviously elevated by increasing the laser power. Accordingly, the resultant viscosity of liquid significantly reduced under a large laser power and was characterized with a large velocity, which was prone to result in a more intensive convection within pool. In this case, the sufficient heat and mass transfer occurred at the interface between the previously fabricated tracks and currently building track, revealing a strongly sufficient spreading between the neighboring tracks and a resultant high-quality surface without obvious porosity. By contrast, the surface quality of SLM-processed components with a relatively low laser power notably weakened due to the limited and insufficient heat and mass transfer at the interface of neighboring tracks. Furthermore, the experimental surface morphologies of the top surface were correspondingly acquired and were in full accordance to the calculated results via simulation.

  12. Selection of single blastocysts for fresh transfer via standard morphology assessment alone and with array CGH for good prognosis IVF patients: results from a randomized pilot study

    Directory of Open Access Journals (Sweden)

    Yang Zhihong

    2012-05-01

    Full Text Available Abstract Background Single embryo transfer (SET remains underutilized as a strategy to reduce multiple gestation risk in IVF, and its overall lower pregnancy rate underscores the need for improved techniques to select one embryo for fresh transfer. This study explored use of comprehensive chromosomal screening by array CGH (aCGH to provide this advantage and improve pregnancy rate from SET. Methods First-time IVF patients with a good prognosis (age Results For patients in Group A (n = 55, 425 blastocysts were biopsied and analyzed via aCGH (7.7 blastocysts/patient. Aneuploidy was detected in 191/425 (44.9% of blastocysts in this group. For patients in Group B (n = 48, 389 blastocysts were microscopically examined (8.1 blastocysts/patient. Clinical pregnancy rate was significantly higher in the morphology + aCGH group compared to the morphology-only group (70.9 and 45.8%, respectively; p = 0.017; ongoing pregnancy rate for Groups A and B were 69.1 vs. 41.7%, respectively (p = 0.009. There were no twin pregnancies. Conclusion Although aCGH followed by frozen embryo transfer has been used to screen at risk embryos (e.g., known parental chromosomal translocation or history of recurrent pregnancy loss, this is the first description of aCGH fully integrated with a clinical IVF program to select single blastocysts for fresh SET in good prognosis patients. The observed aneuploidy rate (44.9% among biopsied blastocysts highlights the inherent imprecision of SET when conventional morphology is used alone. Embryos randomized to the aCGH group implanted with greater efficiency, resulted in clinical pregnancy more often, and yielded a lower miscarriage rate than those selected without aCGH. Additional studies are needed to verify our pilot data and confirm a role for on-site, rapid aCGH for IVF patients contemplating fresh SET.

  13. Early prevention of antisocial personality: long-term follow-up of two randomized controlled trials comparing indicated and selective approaches.

    Science.gov (United States)

    Scott, Stephen; Briskman, Jackie; O'Connor, Thomas G

    2014-06-01

    Antisocial personality is a common adult problem that imposes a major public health burden, but for which there is no effective treatment. Affected individuals exhibit persistent antisocial behavior and pervasive antisocial character traits, such as irritability, manipulativeness, and lack of remorse. Prevention of antisocial personality in childhood has been advocated, but evidence for effective interventions is lacking. The authors conducted two follow-up studies of randomized trials of group parent training. One involved 120 clinic-referred 3- to 7-year-olds with severe antisocial behavior for whom treatment was indicated, 93 of whom were reassessed between ages 10 and 17. The other involved 109 high-risk 4- to 6-year-olds with elevated antisocial behavior who were selectively screened from the community, 90 of whom were reassessed between ages 9 and 13. The primary psychiatric outcome measures were the two elements of antisocial personality, namely, antisocial behavior (assessed by a diagnostic interview) and antisocial character traits (assessed by a questionnaire). Also assessed were reading achievement (an important domain of youth functioning at work) and parent-adolescent relationship quality. In the indicated sample, both elements of antisocial personality were improved in the early intervention group at long-term follow-up compared with the control group (antisocial behavior: odds ratio of oppositional defiant disorder=0.20, 95% CI=0.06, 0.69; antisocial character traits: B=-4.41, 95% CI=-1.12, -8.64). Additionally, reading ability improved (B=9.18, 95% CI=0.58, 18.0). Parental expressed emotion was warmer (B=0.86, 95% CI=0.20, 1.41) and supervision was closer (B=-0.43, 95% CI=-0.11, -0.75), but direct observation of parenting showed no differences. Teacher-rated and self-rated antisocial behavior were unchanged. In contrast, in the selective high-risk sample, early intervention was not associated with improved long-term outcomes. Early intervention with

  14. Mortality of first world war military personnel: comparison of two military cohorts.

    Science.gov (United States)

    Wilson, Nick; Clement, Christine; Summers, Jennifer A; Bannister, John; Harper, Glyn

    2014-12-16

    To identify the impact of the first world war on the lifespan of participating military personnel (including in veterans who survived the war). Comparison of two cohorts of military personnel, followed to death. Military personnel leaving New Zealand to participate in the first world war. From a dataset of the New Zealand Expeditionary Forces, we randomly selected participants who embarked on troopships in 1914 and a comparison non-combat cohort who departed on troopships in late 1918 (350 in each group). Lifespan based on dates of birth and death from a range of sources (such as individual military files and an official database of birth and death records). A quarter of the 1914 cohort died during the war, with deaths from injury predominating (94%) over deaths from disease (6%). This cohort had a significantly shorter lifespan than the late 1918 "non-combat" cohort, with median ages of death being 65.9 versus 74.2, respectively (a difference of 8.3 years shown also in Kaplan-Meier survival curves, log rank Pworld war in 1914 from New Zealand lost around eight years of life (relative to a comparable military cohort). In the postwar period they continued to have an increased risk of premature death. © Wilson et al 2014.

  15. The effects of the adjunctive bupropion on male sexual dysfunction induced by a selective serotonin reuptake inhibitor: a double-blind placebo-controlled and randomized study.

    Science.gov (United States)

    Safarinejad, Mohammad Reza

    2010-09-01

    To determine the safety and efficacy of adjunctive bupropion sustained-release (SR) on male sexual dysfunction (SD) induced by a selective serotonin reuptake inhibitor (SSRI), as SD is a common side-effect of SSRIs and the most effective treatments have yet to be determined. The randomized sample consisted of 234 euthymic men who were receiving some type of SSRI. The men were randomly assigned to bupropion SR (150 mg twice daily, 117) or placebo (twice daily, 117) for 12 weeks. Efficacy was evaluated using the Clinical Global Impression-Sexual Function (CGI-SF; the primary outcome measure), the International Index of Erectile Function (IIEF), Arizona Sexual Experience Scale (ASEX), and Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) (secondary outcome measures). Participants were followed biweekly during study period. After 12 weeks of treatment, the mean (sd) scores for CGI-SF were significantly lower, i.e. better, in patients on bupropion SR, at 2.4 (1.2), than in the placebo group, at 3.9 (1.1) (P= 0.01). Men who received bupropion had a significant increase in the total IIEF score (54.4% vs 1.2%; P= 0.003), and in the five different domains of the IIEF. Total ASEX scores were significantly lower, i.e. better, among men who received bupropion than placebo, at 15.5 (4.3) vs 21.5 (4.7) (P= 0.002). The EDITS scores were 67.4 (10.2) for the bupropion and 36.3 (11.7) for the placebo group (P= 0.001). The ASEX score and CGI-SF score were correlated (P= 0.003). In linear regression analyses the CGI-SF score was not affected significantly by the duration of SD, type of SSRI used and age. Bupropion is an effective treatment for male SD induced by SSRIs. These results provide empirical support for conducting a further study of bupropion.

  16. High mortality in the Thule cohort

    DEFF Research Database (Denmark)

    Juel, K

    1994-01-01

    The objective was to study mortality in the Thule cohort in order to clarify whether it is a selected population and to ascertain the possibility of misinterpretation when national mortality rates are used as reference in the analysis of occupational mortality.......The objective was to study mortality in the Thule cohort in order to clarify whether it is a selected population and to ascertain the possibility of misinterpretation when national mortality rates are used as reference in the analysis of occupational mortality....

  17. Sequence based prediction of DNA-binding proteins based on hybrid feature selection using random forest and Gaussian naïve Bayes.

    Directory of Open Access Journals (Sweden)

    Wangchao Lou

    Full Text Available Developing an efficient method for determination of the DNA-binding proteins, due to their vital roles in gene regulation, is becoming highly desired since it would be invaluable to advance our understanding of protein functions. In this study, we proposed a new method for the prediction of the DNA-binding proteins, by performing the feature rank using random forest and the wrapper-based feature selection using forward best-first search strategy. The features comprise information from primary sequence, predicted secondary structure, predicted relative solvent accessibility, and position specific scoring matrix. The proposed method, called DBPPred, used Gaussian naïve Bayes as the underlying classifier since it outperformed five other classifiers, including decision tree, logistic regression, k-nearest neighbor, support vector machine with polynomial kernel, and support vector machine with radial basis function. As a result, the proposed DBPPred yields the highest average accuracy of 0.791 and average MCC of 0.583 according to the five-fold cross validation with ten runs on the training benchmark dataset PDB594. Subsequently, blind tests on the independent dataset PDB186 by the proposed model trained on the entire PDB594 dataset and by other five existing methods (including iDNA-Prot, DNA-Prot, DNAbinder, DNABIND and DBD-Threader were performed, resulting in that the proposed DBPPred yielded the highest accuracy of 0.769, MCC of 0.538, and AUC of 0.790. The independent tests performed by the proposed DBPPred on completely a large non-DNA binding protein dataset and two RNA binding protein datasets also showed improved or comparable quality when compared with the relevant prediction methods. Moreover, we observed that majority of the selected features by the proposed method are statistically significantly different between the mean feature values of the DNA-binding and the non DNA-binding proteins. All of the experimental results indicate that

  18. The CAP study, evaluation of integrated universal and selective prevention strategies for youth alcohol misuse: study protocol of a cluster randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Newton Nicola C

    2012-08-01

    Full Text Available Abstract Background Alcohol misuse amongst young people is a serious concern. The need for effective prevention is clear, yet there appear to be few evidenced-based programs that prevent alcohol misuse and none that target both high and low-risk youth. The CAP study addresses this gap by evaluating the efficacy of an integrated approach to alcohol misuse prevention, which combines the effective universal internet-based Climate Schools program with the effective selective personality-targeted Preventure program. This article describes the development and protocol of the CAP study which aims to prevent alcohol misuse and related harms in Australian adolescents. Methods/Design A cluster randomized controlled trial (RCT is being conducted with Year 8 students aged 13 to 14-years-old from 27 secondary schools in New South Wales and Victoria, Australia. Blocked randomisation was used to assign schools to one of four groups; Climate Schools only, Preventure only, CAP (Climate Schools and Preventure, or Control (alcohol, drug and health education as usual. The primary outcomes of the trial will be the uptake and harmful use of alcohol and alcohol related harms. Secondary outcomes will include alcohol and cannabis related knowledge, cannabis related harms, intentions to use, and mental health symptomatology. All participants will complete assessments on five occasions; baseline; immediately post intervention, and at 12, 24 and 36 months post baseline. Discussion This study protocol presents the design and current implementation of a cluster RCT to evaluate the efficacy of the CAP study; an integrated universal and selective approach to prevent alcohol use and related harms among adolescents. Compared to students who receive the stand-alone universal Climate Schools program or alcohol and drug education as usual (Controls, we expect the students who receive the CAP intervention to have significantly less uptake of alcohol use, a reduction in average

  19. Spatial and simultaneous seroepidemiology of anti-Leishmania spp. antibodies in dog owners and their dogs from randomly selected households in a major city of southern Brazil.

    Science.gov (United States)

    Benitez, Aline do Nascimento; Martins, Felippe Danyel Cardoso; Mareze, Marcelle; Nino, Beatriz de Souza Lima; Caldart, Eloiza Teles; Ferreira, Fernanda Pinto; Mitsuka-Breganó, Regina; Freire, Roberta Lemos; Galhardo, Juliana Arena; Martins, Camila Marinelli; Biondo, Alexander Welker; Navarro, Italmar Teodorico

    2018-06-01

    Although leishmaniasis has been described as a classic example of a zoonosis requiring a comprehensive approach for control, to date, no study has been conducted on the spatial distribution of simultaneous Leishmania spp. seroprevalence in dog owners and dogs from randomly selected households in urban settings. Accordingly, the present study aimed to simultaneously identify the seroprevalence, spatial distribution and associated factors of infection with Leishmania spp. in dog owners and their dogs in the city of Londrina, a county seat in southern Brazil with a population of half a million people and ranked 18th in population and 145th in the human development index (HDI) out of 5570 Brazilian cities. Overall, 564 households were surveyed and included 597 homeowners and their 729 dogs. Anti-Leishmania spp. antibodies were detected by ELISA in 9/597 (1.50%) dog owners and in 32/729 (4.38%) dogs, with significantly higher prevalence (p = 0.0042) in dogs. Spatial analysis revealed associations between seropositive dogs and households located up to 500 m from the local railway. No clusters were found for either owner or dog case distributions. In summary, the seroepidemiological and spatial results collectively show a lack of association of the factors for infection, and the results demonstrated higher exposure for dogs than their owners. However, railway areas may provide favorable conditions for the maintenance of infected phlebotomines, thereby causing infection in nearby domiciled dogs. In such an urban scenario, local sanitary barriers should be focused on the terrestrial routes of people and surrounding areas, particularly railways, via continuous vector surveillance and identification of phlebotomines infected by Leishmania spp. Copyright © 2018. Published by Elsevier B.V.

  20. An assessment of the quality of care for children in eighteen randomly selected district and sub-district hospitals in Bangladesh

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    Hoque Dewan ME

    2012-12-01

    Full Text Available Abstract Background Quality hospital care is important in ensuring that the needs of severely ill children are met to avert child mortality. However, the quality of hospital care for children in developing countries has often been found poor. As the first step of a country road map for improving hospital care for children, we assessed the baseline situation with respect to the quality of care provided to children under-five years age in district and sub-district level hospitals in Bangladesh. Methods Using adapted World Health Organization (WHO hospital assessment tools and standards, an assessment of 18 randomly selected district (n=6 and sub-district (n=12 hospitals was undertaken. Teams of trained assessors used direct case observation, record review, interviews, and Management Information System (MIS data to assess the quality of clinical case management and monitoring; infrastructure, processes and hospital administration; essential hospital and laboratory supports, drugs and equipment. Results Findings demonstrate that the overall quality of care provided in these hospitals was poor. No hospital had a functioning triage system to prioritise those children most in need of immediate care. Laboratory supports and essential equipment were deficient. Only one hospital had all of the essential drugs for paediatric care. Less than a third of hospitals had a back-up power supply, and just under half had functioning arrangements for safe-drinking water. Clinical case management was found to be sub-optimal for prevalent illnesses, as was the quality of neonatal care. Conclusion Action is needed to improve the quality of paediatric care in hospital settings in Bangladesh, with a particular need to invest in improving newborn care.

  1. Effectiveness of a selective intervention program targeting personality risk factors for alcohol misuse among young adolescents: results of a cluster randomized controlled trial

    NARCIS (Netherlands)

    Lammers, J.; Goossens, F.; Conrod, P.; Engels, R.C.M.E.; Wiers, R.W.H.J.; Kleinjan, M.

    2015-01-01

    Aim The effectiveness of Preventure was tested on drinking behaviour of young adolescents in secondary education in the Netherlands. Design A cluster randomized controlled trial was carried out, with participants assigned randomly to a two-session coping skills intervention or a control

  2. Randomizing Roaches: Exploring the "Bugs" of Randomization in Experimental Design

    Science.gov (United States)

    Wagler, Amy; Wagler, Ron

    2014-01-01

    Understanding the roles of random selection and random assignment in experimental design is a central learning objective in most introductory statistics courses. This article describes an activity, appropriate for a high school or introductory statistics course, designed to teach the concepts, values and pitfalls of random selection and assignment…

  3. Brief Report: Estimated Prevalence of a Community Diagnosis of Autism Spectrum Disorder by Age 4 Years in Children from Selected Areas in the United States in 2010--Evaluation of Birth Cohort Effects

    Science.gov (United States)

    Soke, Gnakub N.; Maenner, M. J.; Christensen, D.; Kurzius-Spencer, M.; Schieve, L. A.

    2017-01-01

    We compared early-diagnosed autism spectrum disorder (ASD) (defined as diagnosis by age 4 years) between the 2002 and 2006 birth cohorts, in five sites of the Autism and Developmental Disabilities Monitoring Network. In the 2002 cohort, the prevalence/1000 of early-diagnosed ASD was half the 8-year-old prevalence (7.2 vs. 14.7, prevalence ratio…

  4. A randomized control trial to evaluate the effect of adjuvant selective laser trabeculoplasty versus medication alone in primary open-angle glaucoma: preliminary results

    Directory of Open Access Journals (Sweden)

    Lee JWY

    2014-09-01

    Full Text Available Jacky WY Lee,1,2 Catherine WS Chan,2 Mandy OM Wong,3 Jonathan CH Chan,3 Qing Li,2 Jimmy SM Lai2 1The Department of Ophthalmology, Caritas Medical Centre, 2The Department of Ophthalmology, The University of Hong Kong, 3The Department of Ophthalmology, Queen Mary Hospital, Hong Kong Background: The objective of this study was to investigate the effects of adjuvant selective laser trabeculoplasty (SLT versus medication alone on intraocular pressure (IOP control, medication use, and quality of life in patients with primary open-angle glaucoma.Methods: This prospective, randomized control study recruited 41 consecutive primary open-angle glaucoma subjects with medically-controlled IOP ≤21 mmHg. The SLT group (n=22 received a single 360-degree SLT treatment. The medication-only group (n=19 continued with their usual treatment regimen. In both groups, medication was titrated to maintain a target IOP defined as a 25% reduction from baseline IOP without medication, or <18 mmHg, whichever was lower. Outcomes, which were measured at baseline and at 6 months, included the Glaucoma Quality of Life-15 (GQL-15 and Comparison of Ophthalmic Medications for Tolerability (COMTOL survey scores, IOP, and the number of antiglaucoma medicines. Results: The baseline IOP was 15.8±2.7 mmHg and 14.5±2.5 mmHg in the SLT and medication-only groups, respectively (P=0.04. Both groups had a comparable number of baseline medication (P=0.2, GQL-15 (P=0.3 and COMTOL scores (P=0.7. At 6 months, the SLT group had a lower IOP (P=0.03 and required fewer medications compared with both baseline (P<0.0001 and with the medication-only group (P=0.02. There was no statistically significant difference in the 6-month GQL-15 or COMTOL score as compared to baseline (P≥0.4 or between the two treatment groups (P≥0.2.Conclusion: A single session of adjuvant SLT provided further reductions in IOP and medication without substantial changes in quality of life or medication tolerability at 6

  5. On Random Numbers and Design

    Science.gov (United States)

    Ben-Ari, Morechai

    2004-01-01

    The term "random" is frequently used in discussion of the theory of evolution, even though the mathematical concept of randomness is problematic and of little relevance in the theory. Therefore, since the core concept of the theory of evolution is the non-random process of natural selection, the term random should not be used in teaching the…

  6. Risk of thyroid cancer in patients with thyroiditis: a population-based cohort study.

    Science.gov (United States)

    Liu, Chien-Liang; Cheng, Shih-Ping; Lin, Hui-Wen; Lai, Yuen-Liang

    2014-03-01

    The causative relationship between autoimmune thyroiditis and thyroid cancer remains a controversial issue. The aim of this population-based study was to investigate the risk of thyroid cancer in patients with thyroiditis. From the Longitudinal Health Insurance Database 2005 (LHID2005) of Taiwan, we identified adult patients newly diagnosed with thyroiditis between 2004 and 2009 (n = 1,654). The comparison cohort (n = 8,270) included five randomly selected age- and sex-matched controls for each patient in the study cohort. All patients were followed up from the date of cohort entry until they developed thyroid cancer or to the end of 2010. Multivariate Cox regression was used to assess the risk of developing thyroid cancer. A total of 1,000 bootstrap replicates were created for internal validation. A total of 35 patients developed thyroid cancer during the study period, of whom 24 were from the thyroiditis cohort and 11 were from the comparison cohort (incidence 353 and 22 per 100,000 person-years, respectively). After adjusting for potential confounding factors, the hazard ratio (HR) for thyroid cancer in patients with thyroiditis was 13.24 (95 % CI 6.40-27.39). Excluding cancers occurring within 1 year of follow-up, the HR remained significantly increased (6.64; 95 % CI 2.35-18.75). Hypothyroidism was not an independent factor associated with the occurrence of thyroid cancer. We found an increased risk for the development of thyroid cancer after a diagnosis of thyroiditis, independent of comorbidities.

  7. Exposure-response relationships for select cancer and non-cancer health outcomes in a cohort of U.S. firefighters from San Francisco, Chicago and Philadelphia (1950-2009).

    Science.gov (United States)

    Daniels, Robert D; Bertke, Stephen; Dahm, Matthew M; Yiin, James H; Kubale, Travis L; Hales, Thomas R; Baris, Dalsu; Zahm, Shelia H; Beaumont, James J; Waters, Kathleen M; Pinkerton, Lynne E

    2015-10-01

    To examine exposure-response relationships between surrogates of firefighting exposure and select outcomes among previously studied US career firefighters. Eight cancer and four non-cancer outcomes were examined using conditional logistic regression. Incidence density sampling was used to match each case to 200 controls on attained age. Days accrued in firefighting assignments (exposed-days), run totals (fire-runs) and run times (fire-hours) were used as exposure surrogates. HRs comparing 75th and 25th centiles of lagged cumulative exposures were calculated using loglinear, linear, log-quadratic, power and restricted cubic spline general relative risk models. Piecewise constant models were used to examine risk differences by time since exposure, age at exposure and calendar period. Among 19,309 male firefighters eligible for the study, there were 1333 cancer deaths and 2609 cancer incidence cases. Significant positive associations between fire-hours and lung cancer mortality and incidence were evident. A similar relation between leukaemia mortality and fire-runs was also found. The lung cancer associations were nearly linear in cumulative exposure, while the association with leukaemia mortality was attenuated at higher exposure levels and greater for recent exposures. Significant negative associations were evident for the exposure surrogates and colorectal and prostate cancers, suggesting a healthy worker survivor effect possibly enhanced by medical screening. Lung cancer and leukaemia mortality risks were modestly increasing with firefighter exposures. These findings add to evidence of a causal association between firefighting and cancer. Nevertheless, small effects merit cautious interpretation. We plan to continue to follow the occurrence of disease and injury in this cohort. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  8. Influence of motor skills training on children's development evaluated in the Motor skills in PreSchool (MiPS) study-DK: study protocol for a randomized controlled trial, nested in a cohort study.

    Science.gov (United States)

    Hestbaek, Lise; Andersen, Sarah Thurøe; Skovgaard, Thomas; Olesen, Line Groenholt; Elmose, Mette; Bleses, Dorthe; Andersen, Simon Calmar; Lauridsen, Henrik Hein

    2017-08-29

    Good motor skills are considered important for children's physical, social, and psychological development, but the relationship is still poorly understood. Preschool age seems to be decisive for the development of motor skills and probably the most promising time-window in relation to preventive strategies based on improved motor skills. This research program has four overall aims: (1) investigation of the effect of a structured program aimed at improving motor skills in 3-6-year-old children on current and future motor skills, health, cognition, and wellbeing; (2) establish reference data on motor skills in 3-6-year-olds; (3) description of early development of musculoskeletal problems; and (4) establishment of a population-based cohort of 3-6-year-olds. Over a four-year period, all preschools in a Danish municipality, Svendborg, will implement a new program aimed at optimizing children's motor skills. By introducing the program into a subset of the preschools at onset and comparing these children to another subset (control) that will not receive the intervention the first three years, it is possible to document a potential effect of the intervention. At the same time, a cohort will be established including all children attending preschools in the municipality with extensive baseline data collection: gross and fine motor skills; movement patterns; musculoskeletal complaints; physical activity; anthropometry; general wellbeing; cognitive abilities; language status; medical history; demographic background; and more. The children are aged 3-6 years at baseline. A total of 1461 children have been invited into the cohort, 368 to the intervention arm and 359 to the control arm. Follow-up time for the trial is 2.5 years. The cohort is planned to run at least until the children leave school at age 15-16 years. Longer follow-up will depend on future funding. If the results of the trial are positive, the intervention can be implemented in other similar settings with

  9. Pharmacodynamics and safety of the novel selective progesterone receptor modulator vilaprisan: a double-blind, randomized, placebo-controlled phase 1 trial in healthy women.

    Science.gov (United States)

    Schütt, Barbara; Kaiser, Andreas; Schultze-Mosgau, Marcus-Hillert; Seitz, Christian; Bell, David; Koch, Manuela; Rohde, Beate

    2016-08-01

    Does administration of vilaprisan (VPR) to healthy women for 12 weeks reduce menstrual bleeding? In this 12-week proof-of-concept phase 1 trial, most women (30/33, 90%) who received VPR at daily doses of 1-5 mg reported the absence of menstrual bleeding. Vilaprisan (BAY 1002670) is a novel, highly potent selective progesterone receptor modulator that markedly reduces the growth of human leiomyoma tissue in a preclinical model of uterine fibroids (UFs). In this double-blind, parallel-group study, of the 163 healthy women enrolled 73 were randomized to daily VPR 0.1 mg (n = 12), 0.5 mg (n = 12), 1 mg (n = 13), 2 mg (n = 12), 5 mg (n = 12) or placebo tablets (n = 12) for 12 weeks. Participants were followed up until the start of the second menstrual bleeding after the end of treatment. Trial simulations were used to determine the minimum sample size required to estimate the non-bleeding rate (i.e. self-assessed bleeding intensity of 'none' or 'spotting') using Bayesian dose-response estimation with incorporated prior information. It was estimated that 48 participants in the per-protocol analysis population would be sufficient. Women aged 18-45 years who had been sterilized by tubal ligation were enrolled between November 2011 and May 2012. Participants kept a daily diary of bleeding intensity. Blood and urine samples were taken, and transvaginal ultrasound was performed before treatment, during treatment and follow-up. Endometrial biopsies were obtained during the pretreatment cycle, at the end of the treatment period and during the follow-up phase. The primary outcome was the estimated dose-response curve of the observed non-bleeding rate during Days 10-84 of treatment, excluding the endometrial biopsy day and 2 days after biopsy. Secondary outcomes included return of bleeding during follow-up, size of follicle-like structures and serum hormone levels. Safety assessments included adverse events (AEs), endometrial thickness and histology, laboratory parameters, vital

  10. Effectiveness of adjuvant radiotherapy in patients with oropharyngeal and floor of mouth squamous cell carcinoma and concomitant histological verification of singular ipsilateral cervical lymph node metastasis (pN1-state - A prospective multicenter randomized controlled clinical trial using a comprehensive cohort design

    Directory of Open Access Journals (Sweden)

    Wendt Thomas G

    2009-12-01

    Full Text Available Abstract Background Modern radiotherapy plays an important role in therapy of advanced head and neck carcinomas. However, no clinical studies have been published addressing the effectiveness of postoperative radiotherapy in patients with small tumor (pT1, pT2 and concomitant ipsilateral metastasis of a single lymph node (pN1, which would provide a basis for a general treatment recommendation. Methods/Design The present study is a non-blinded, prospective, multi-center randomized controlled trial (RCT. As the primary clinical endpoint, overall-survival in patients receiving postoperative radiation therapy vs. patients without adjuvant therapy following curative intended surgery is compared. The aim of the study is to enroll 560 adult males and females for 1:1 randomization to one of the two treatment arms (irradiation/no irradiation. Since patients with small tumor (T1/T2 but singular lymph node metastasis are rare and the amount of patients consenting to randomization is not predictable in advance, all patients rejecting randomization will be treated as preferred and enrolled in a prospective observational study (comprehensive cohort design after giving informed consent. This observational part of the trial will be performed with maximum consistency to the treatment and observation protocol of the RCT. Because the impact of patient preference for a certain treatment option is not calculable, parallel design of RCT and observational study may provide a maximum of evidence and efficacy for evaluation of treatment outcome. Secondary clinical endpoints are as follows: incidence and time to tumor relapse (locoregional relapse, lymph node involvement and distant metastatic spread, Quality of life as reported by EORTC (QLQ-C30 with H&N 35 module, and time from operation to orofacial rehabilitation. All tumors represent a homogeneous clinical state and therefore additional investigation of protein expression levels within resection specimen may serve

  11. Effectiveness of adjuvant radiotherapy in patients with oropharyngeal and floor of mouth squamous cell carcinoma and concomitant histological verification of singular ipsilateral cervical lymph node metastasis (pN1-state) - A prospective multicenter randomized controlled clinical trial using a comprehensive cohort design

    Science.gov (United States)

    2009-01-01

    Background Modern radiotherapy plays an important role in therapy of advanced head and neck carcinomas. However, no clinical studies have been published addressing the effectiveness of postoperative radiotherapy in patients with small tumor (pT1, pT2) and concomitant ipsilateral metastasis of a single lymph node (pN1), which would provide a basis for a general treatment recommendation. Methods/Design The present study is a non-blinded, prospective, multi-center randomized controlled trial (RCT). As the primary clinical endpoint, overall-survival in patients receiving postoperative radiation therapy vs. patients without adjuvant therapy following curative intended surgery is compared. The aim of the study is to enroll 560 adult males and females for 1:1 randomization to one of the two treatment arms (irradiation/no irradiation). Since patients with small tumor (T1/T2) but singular lymph node metastasis are rare and the amount of patients consenting to randomization is not predictable in advance, all patients rejecting randomization will be treated as preferred and enrolled in a prospective observational study (comprehensive cohort design) after giving informed consent. This observational part of the trial will be performed with maximum consistency to the treatment and observation protocol of the RCT. Because the impact of patient preference for a certain treatment option is not calculable, parallel design of RCT and observational study may provide a maximum of evidence and efficacy for evaluation of treatment outcome. Secondary clinical endpoints are as follows: incidence and time to tumor relapse (locoregional relapse, lymph node involvement and distant metastatic spread), Quality of life as reported by EORTC (QLQ-C30 with H&N 35 module), and time from operation to orofacial rehabilitation. All tumors represent a homogeneous clinical state and therefore additional investigation of protein expression levels within resection specimen may serve for establishment of

  12. Effectiveness of adjuvant radiotherapy in patients with oropharyngeal and floor of mouth squamous cell carcinoma and concomitant histological verification of singular ipsilateral cervical lymph node metastasis (pN1-state)--a prospective multicenter randomized controlled clinical trial using a comprehensive cohort design.

    Science.gov (United States)

    Moergel, Maximilian; Jahn-Eimermacher, Antje; Krummenauer, Frank; Reichert, Torsten E; Wagner, Wilfried; Wendt, Thomas G; Werner, Jochen A; Al-Nawas, Bilal

    2009-12-23

    Modern radiotherapy plays an important role in therapy of advanced head and neck carcinomas. However, no clinical studies have been published addressing the effectiveness of postoperative radiotherapy in patients with small tumor (pT1, pT2) and concomitant ipsilateral metastasis of a single lymph node (pN1), which would provide a basis for a general treatment recommendation. The present study is a non-blinded, prospective, multi-center randomized controlled trial (RCT). As the primary clinical endpoint, overall-survival in patients receiving postoperative radiation therapy vs. patients without adjuvant therapy following curative intended surgery is compared. The aim of the study is to enroll 560 adult males and females for 1:1 randomization to one of the two treatment arms (irradiation/no irradiation). Since patients with small tumor (T1/T2) but singular lymph node metastasis are rare and the amount of patients consenting to randomization is not predictable in advance, all patients rejecting randomization will be treated as preferred and enrolled in a prospective observational study (comprehensive cohort design) after giving informed consent. This observational part of the trial will be performed with maximum consistency to the treatment and observation protocol of the RCT. Because the impact of patient preference for a certain treatment option is not calculable, parallel design of RCT and observational study may provide a maximum of evidence and efficacy for evaluation of treatment outcome. Secondary clinical endpoints are as follows: incidence and time to tumor relapse (locoregional relapse, lymph node involvement and distant metastatic spread), Quality of life as reported by EORTC (QLQ-C30 with H&N 35 module), and time from operation to orofacial rehabilitation. All tumors represent a homogeneous clinical state and therefore additional investigation of protein expression levels within resection specimen may serve for establishment of surrogate parameters of

  13. Randomization tests

    CERN Document Server

    Edgington, Eugene

    2007-01-01

    Statistical Tests That Do Not Require Random Sampling Randomization Tests Numerical Examples Randomization Tests and Nonrandom Samples The Prevalence of Nonrandom Samples in Experiments The Irrelevance of Random Samples for the Typical Experiment Generalizing from Nonrandom Samples Intelligibility Respect for the Validity of Randomization Tests Versatility Practicality Precursors of Randomization Tests Other Applications of Permutation Tests Questions and Exercises Notes References Randomized Experiments Unique Benefits of Experiments Experimentation without Mani

  14. Academic Performance in Adolescence after Inguinal Hernia Repair in Infancy: A Nationwide Cohort Study

    DEFF Research Database (Denmark)

    Hansen, Tom G; Pedersen, Jacob K; Henneberg, Steen W

    2011-01-01

    for inguinal hernia repair in infancy and subsequent academic performance. METHODS:: Using Danish birth cohorts from 1986-1990, we compared the academic performance of all children who had undergone inguinal hernia repair in infancy to a randomly selected, age-matched 5% population sample. Primary analysis...... found no evidence that a single, relatively brief anesthetic exposure in connection with hernia repair in infancy reduced academic performance at age 15 or 16 yr after adjusting for known confounding factors. However, the higher test score nonattainment rate among the hernia group could suggest...... repair in infancy. A randomly selected, age-matched 5% population sample consists of 14,575 individuals. Although the exposure group performed worse than the control group (average score 0.26 lower; 95% CI, 0.21-0.31), after adjusting for known confounders, no statistically significant difference (-0...

  15. Academic Performance in Adolescence after Inguinal Hernia Repair in Infancy: A Nationwide Cohort Study

    DEFF Research Database (Denmark)

    Hansen, Tom G; Pedersen, Jacob K; Henneberg, Steen Winther

    2011-01-01

    for inguinal hernia repair in infancy and subsequent academic performance. METHODS:: Using Danish birth cohorts from 1986-1990, we compared the academic performance of all children who had undergone inguinal hernia repair in infancy to a randomly selected, age-matched 5% population sample. Primary analysis...... compared average test scores at ninth grade adjusting for sex, birth weight, and paternal and maternal age and education. Secondary analysis compared the proportions of children not attaining test scores between the two groups. RESULTS:: From 1986-1990 in Denmark, 2,689 children underwent inguinal hernia...... repair in infancy. A randomly selected, age-matched 5% population sample consists of 14,575 individuals. Although the exposure group performed worse than the control group (average score 0.26 lower; 95% CI, 0.21-0.31), after adjusting for known confounders, no statistically significant difference (-0...

  16. Selepressin, a novel selective vasopressin V1A agonist, is an effective substitute for norepinephrine in a phase IIa randomized, placebo-controlled trial in septic shock patients

    DEFF Research Database (Denmark)

    Russell, James A; Vincent, Jean-Louis; Kjølbye, Anne Louise

    2017-01-01

    BACKGROUND: Vasopressin is widely used for vasopressor support in septic shock patients, but experimental evidence suggests that selective V1A agonists are superior. The initial pharmacodynamic effects, pharmacokinetics, and safety of selepressin, a novel V1A-selective vasopressin analogue, was e...

  17. The effect of barusiban, a selective oxytocin antagonist, in threatened preterm labor at late gestational age: a randomized, double-blind, placebo-controlled trial

    DEFF Research Database (Denmark)

    Thornton, Steven; Goodwin, Thomas M; Greisen, Gorm

    2009-01-01

    OBJECTIVE: The objective of the study was to compare barusiban with placebo in threatened preterm labor. STUDY DESIGN: This was a randomized, double-blind, placebo-controlled, multicenter study. One hundred sixty-three women at 34-35 weeks plus 6 days, and with 6 or more contractions of 30 seconds...

  18. NWHSS Implement Family Member Assessment Component in the Millennium Cohort Study

    Science.gov (United States)

    2012-10-01

    Response and Referral Rates (McMaster) Panel 4 Impact of Cognitive Dissonance Improvement Strategies *Open Discussion* Family Improvement... Cognitive Dissonance (Via Effort Justification) Study  This pilot study utilized a random selection of married Panel 4 Millennium Cohort members taking...Spousal and family  functioning  Determine service member  factors that are associated  with spouse reports of  marital  satisfaction  and  family

  19. [Comparison on Endoscopic Hemoclip and Hemoclip Combination Therapy in Non-variceal Upper Gastrointestinal Bleeding Patients Based on Clinical Practice Data: Is There Difference between Prospective Cohort Study and Randomized Study?].

    Science.gov (United States)

    Lee, Su Hyun; Jung, Jin Tae; Lee, Dong Wook; Ha, Chang Yoon; Park, Kyung Sik; Lee, Si Hyung; Yang, Chang Heon; Park, Youn Sun; Jeon, Seong Woo

    2015-08-01

    Endoscopic hemoclip application is an effective and safe method of endoscopic hemostasis. We conducted a multicenter retrospective study on hemoclip and hemoclip combination therapy based on prospective cohort database in terms of hemostatic efficacy not in clinical trial but in real clinical practice. Data on endoscopic hemostasis for non-variceal upper gastrointestinal bleeding (NVUGIB) were prospectively collected from February 2011 to December 2013. Among 1,584 patients with NVUGIB, 186 patients treated with hemoclip were enrolled in this study. Subjects were divided into three groups: Group 1 (n = 62), hemoclipping only; group 2 (n = 88), hemoclipping plus epinephrine injection; and group 3 (n = 36), hemocliping and epinephrine injection plus other endoscopic hemostatic modalities. Primary outcomes included rebleeding, other therapeutic management, hospitalization period, fasting period and mortality. Secondary outcomes were bleeding associated mortality and overall mortality. Active bleeding and peptic ulcer bleeding were more common in group 3 than in group 1 and in group 2 (p bleeding associated mortality and total mortality) were not different among groups. Combination therapy of epinephrine injection and other modalities with hemoclips did not show advantage over hemoclipping alone in this prospective cohort study. However, there is a tendency to perform combination therapy in active bleeding which resulted in equivalent hemostatic success rate, and this reflects the role of combination therapy in clinical practice.

  20. Prevalence, diagnostics and management of musculoskeletal disorders in primary health care in Sweden : an investigation of 2000 randomly selected patient records

    OpenAIRE

    Wiitavaara, Birgitta; Fahlström, Martin; Djupsjöbacka, Mats

    2017-01-01

    Abstract Rationale, aims and objectives The aims of this study is to investigate the prevalence of patients seeking care due to different musculoskeletal disorders (MSDs) at primary health care centres (PHCs), to chart different factors such as symptoms, diagnosis and actions prescribed for patients that visited the PHCs due to MSD and to make comparisons regarding differences due to gender, age and rural or urban PHC. Methods Patient records (2000) for patients in working age were randomly s...

  1. Treatment of Implant Exposure due to Skin Necroses after Skin Sparing Mastectomy: Initial Experiences Using a Not Selective Random Epigastric Flap.

    Science.gov (United States)

    Echazarreta-Gallego, Estíbaliz; Pola-Bandrés, Guillermo; Arribas-Del Amo, María Dolores; Gil-Romea, Ismael; Sousa-Domínguez, Ramón; Güemes-Sánchez, Antonio

    2017-10-01

    Breast prostheses exposure is probably the most devastating complication after a skin sparing mastectomy (SSM) and implant-based, one-stage, breast reconstruction. This complication may occur in the immediate post-operative period or in the weeks and even months after the procedure. In most cases, the cause is poor skin coverage of the implant due to skin necrosis. Eight consecutive cases of implant exposure (or risk of exposure) due to skin necrosis in SSM patients over a period of 5 years, all patients were treated using a random epigastric rotation flap, executed by the same medical team. A random epigastric flap (island or conventional rotation flap) was used to cover the skin defect. All the patients completed the procedure and all prostheses were saved; there were no cases of flap necrosis or infection. Cases of skin necrosis after SSM and immediate implant reconstruction, in which the implant is at risk of exposure, can be successfully treated with a random epigastric rotation flap.

  2. Oral clefts and life style factors - a case-cohort study based on prospective Danish data

    DEFF Research Database (Denmark)

    Bille, Camilla; Olsen, Jørn; Vach, Werner

    2007-01-01

    supplementation with > or =400 mcg folic acid daily during the entire first trimester (OR: 0.75; CIs: 0.46, 1.22) suggested an inverse associated with oral clefts, similar to our results on coffee drinking. No effects were found for smaller doses of folic acid, vitamin A, B6 or B12 in this study. The present......This study examines the association between oral clefts and first trimester maternal lifestyle factors based on prospective data from the Danish National Birth Cohort. The cohort includes approximately 100,000 pregnancies. In total 192 mothers gave birth to child with an oral cleft during 1997......-2003. Information on risk factors such as smoking, alcohol consumption, tea, coffee, cola, and food supplements was obtained during pregnancy for these and 828 randomly selected controls. We found that first trimester maternal smoking was associated with an increased risk of oral clefts (odds ratio (OR): 1.50; 95...

  3. Effect of mirtazapine versus selective serotonin reuptake inhibitors on benzodiazepine use in patients with major depressive disorder: a pragmatic, multicenter, open-label, randomized, active-controlled, 24-week trial.

    Science.gov (United States)

    Hashimoto, Tasuku; Shiina, Akihiro; Hasegawa, Tadashi; Kimura, Hiroshi; Oda, Yasunori; Niitsu, Tomihisa; Ishikawa, Masatomo; Tachibana, Masumi; Muneoka, Katsumasa; Matsuki, Satoshi; Nakazato, Michiko; Iyo, Masaomi

    2016-01-01

    This study aimed to evaluate whether selecting mirtazapine as the first choice for current depressive episode instead of selective serotonin reuptake inhibitors (SSRIs) reduces benzodiazepine use in patients with major depressive disorder (MDD). We concurrently examined the relationship between clinical responses and serum mature brain-derived neurotrophic factor (BDNF) and its precursor, proBDNF. We conducted an open-label randomized trial in routine psychiatric practice settings. Seventy-seven MDD outpatients were randomly assigned to the mirtazapine or predetermined SSRIs groups, and investigators arbitrarily selected sertraline or paroxetine. The primary outcome was the proportion of benzodiazepine users at weeks 6, 12, and 24 between the groups. We defined patients showing a ≥50 % reduction in Hamilton depression rating scale (HDRS) scores from baseline as responders. Blood samples were collected at baseline, weeks 6, 12, and 24. Sixty-five patients prescribed benzodiazepines from prescription day 1 were analyzed for the primary outcome. The percentage of benzodiazepine users was significantly lower in the mirtazapine than in the SSRIs group at weeks 6, 12, and 24 (21.4 vs. 81.8 %; 11.1 vs. 85.7 %, both P  depressive episodes may reduce benzodiazepine use in patients with MDD. Trial registration UMIN000004144. Registered 2nd September 2010. The date of enrolment of the first participant to the trial was 24th August 2010. This study was retrospectively registered 9 days after the first participant was enrolled.

  4. Influence of motor skills training on children’s development evaluated in the Motor skills in PreSchool (MiPS) study-DK: study protocol for a randomized controlled trial, nested in a cohort study

    DEFF Research Database (Denmark)

    Hestbaek, Lise; Andersen, Sara Thurøe; Skovgaard, Thomas

    2017-01-01

    BACKGROUND: Good motor skills are considered important for children's physical, social, and psychological development, but the relationship is still poorly understood. Preschool age seems to be decisive for the development of motor skills and probably the most promising time-window in relation...... to preventive strategies based on improved motor skills. This research program has four overall aims: (1) investigation of the effect of a structured program aimed at improving motor skills in 3-6-year-old children on current and future motor skills, health, cognition, and wellbeing; (2) establish reference...... data on motor skills in 3-6-year-olds; (3) description of early development of musculoskeletal problems; and (4) establishment of a population-based cohort of 3-6-year-olds. METHODS: Over a four-year period, all preschools in a Danish municipality, Svendborg, will implement a new program aimed...

  5. Selected CD133⁺ progenitor cells to promote angiogenesis in patients with refractory angina: final results of the PROGENITOR randomized trial.

    Science.gov (United States)

    Jimenez-Quevedo, Pilar; Gonzalez-Ferrer, Juan Jose; Sabate, Manel; Garcia-Moll, Xavier; Delgado-Bolton, Roberto; Llorente, Leopoldo; Bernardo, Esther; Ortega-Pozzi, Aranzazu; Hernandez-Antolin, Rosana; Alfonso, Fernando; Gonzalo, Nieves; Escaned, Javier; Bañuelos, Camino; Regueiro, Ander; Marin, Pedro; Fernandez-Ortiz, Antonio; Neves, Barbara Das; Del Trigo, Maria; Fernandez, Cristina; Tejerina, Teresa; Redondo, Santiago; Garcia, Eulogio; Macaya, Carlos

    2014-11-07

    Refractory angina constitutes a clinical problem. The aim of this study was to assess the safety and the feasibility of transendocardial injection of CD133(+) cells to foster angiogenesis in patients with refractory angina. In this randomized, double-blinded, multicenter controlled trial, eligible patients were treated with granulocyte colony-stimulating factor, underwent an apheresis and electromechanical mapping, and were randomized to receive treatment with CD133(+) cells or no treatment. The primary end point was the safety of transendocardial injection of CD133(+) cells, as measured by the occurrence of major adverse cardiac and cerebrovascular event at 6 months. Secondary end points analyzed the efficacy. Twenty-eight patients were included (n=19 treatment; n=9 control). At 6 months, 1 patient in each group had ventricular fibrillation and 1 patient in each group died. One patient (treatment group) had a cardiac tamponade during mapping. There were no significant differences between groups with respect to efficacy parameters; however, the comparison within groups showed a significant improvement in the number of angina episodes per month (median absolute difference, -8.5 [95% confidence interval, -15.0 to -4.0]) and in angina functional class in the treatment arm but not in the control group. At 6 months, only 1 simple-photon emission computed tomography (SPECT) parameter: summed score improved significantly in the treatment group at rest and at stress (median absolute difference, -1.0 [95% confidence interval, -1.9 to -0.1]) but not in the control arm. Our findings support feasibility and safety of transendocardial injection of CD133(+) cells in patients with refractory angina. The promising clinical results and favorable data observed in SPECT summed score may set up the basis to test the efficacy of cell therapy in a larger randomized trial. © 2014 American Heart Association, Inc.

  6. The selective serotonin reuptake inhibitor fluoxetine does not change rectal sensitivity and symptoms in patients with irritable bowel syndrome: a double blind, randomized, placebo-controlled study

    NARCIS (Netherlands)

    Kuiken, Sjoerd D.; Tytgat, Guido N. J.; Boeckxstaens, Guy E. E.

    2003-01-01

    BACKGROUND & AIMS: Although widely prescribed, the evidence for the use of antidepressants for the treatment of irritable bowel syndrome (IBS) is limited. In this study, we hypothesized that fluoxetine (Prozac), a selective serotonin reuptake inhibitor, has visceral analgesic properties, leading to

  7. A sequential logic circuit for coincidences randomly distributed in 'time' and 'duration', with selection and total sampling

    International Nuclear Information System (INIS)

    Carnet, Bernard; Delhumeau, Michel

    1971-06-01

    The principles of binary analysis applied to the investigation of sequential circuits were used to design a two way coincidence circuit whose input may be, random or periodic variables of constant or variable duration. The output signal strictly reproduces the characteristics of the input signal triggering the coincidence. A coincidence between input signals does not produce any output signal if one of the signals has already triggered the output signal. The characteristics of the output signal in relation to those of the input signal are: minimum time jitter, excellent duration reproducibility and maximum efficiency. Some rules are given for achieving these results. The symmetry, transitivity and non-transitivity characteristics of the edges on the primitive graph are analyzed and lead to some rules for positioning the states on a secondary graph. It is from this graph that the equations of the circuits can be calculated. The development of the circuit and its dynamic testing are discussed. For this testing, the functioning of the circuit is simulated by feeding into the input randomly generated signals

  8. Impact of selected magnetic fields on the therapeutic effect in patients with lumbar discopathy: A prospective, randomized, single-blinded, and placebo-controlled clinical trial.

    Science.gov (United States)

    Taradaj, Jakub; Ozon, Marcin; Dymarek, Robert; Bolach, Bartosz; Walewicz, Karolina; Rosińczuk, Joanna

    2018-03-23

    Interdisciplinary physical therapy together with pharmacological treatment constitute conservative treatment strategies related to low back pain (LBP). There is still a lack of high quality studies aimed at an objective evaluation of physiotherapeutic procedures according to their effectiveness in LBP. The aim of this study is to carry out a prospective, randomized, single-blinded, and placebocontrolled clinical trial to evaluate the effectiveness of magnetic fields in discopathy-related LBP. A group of 177 patients was assessed for eligibility based on inclusion and exclusion criteria. In the end, 106 patients were randomly assigned into 5 comparative groups: A (n = 23; magnetic therapy: 10 mT, 50 Hz); B (n = 23; magnetic therapy: 5 mT, 50 Hz); C (n = 20; placebo magnetic therapy); D (n = 20; magnetic stimulation: 49.2 μT, 195 Hz); and E (n = 20; placebo magnetic stimulation). All patients were assessed using tests for pain intensity, degree of disability and range of motion. Also, postural stability was assessed using a stabilographic platform. In this study, positive changes in all clinical outcomes were demonstrated in group A (p 0.05). It was determined that the application of magnetic therapy (10 mT, 50 Hz, 20 min) significantly reduces pain symptoms and leads to an improvement of functional ability in patients with LBP.

  9. The RANDOM computer program: A linear congruential random number generator

    Science.gov (United States)

    Miles, R. F., Jr.

    1986-01-01

    The RANDOM Computer Program is a FORTRAN program for generating random number sequences and testing linear congruential random number generators (LCGs). The linear congruential form of random number generator is discussed, and the selection of parameters of an LCG for a microcomputer described. This document describes the following: (1) The RANDOM Computer Program; (2) RANDOM.MOD, the computer code needed to implement an LCG in a FORTRAN program; and (3) The RANCYCLE and the ARITH Computer Programs that provide computational assistance in the selection of parameters for an LCG. The RANDOM, RANCYCLE, and ARITH Computer Programs are written in Microsoft FORTRAN for the IBM PC microcomputer and its compatibles. With only minor modifications, the RANDOM Computer Program and its LCG can be run on most micromputers or mainframe computers.

  10. Random walk on random walks

    NARCIS (Netherlands)

    Hilário, M.; Hollander, den W.Th.F.; Sidoravicius, V.; Soares dos Santos, R.; Teixeira, A.

    2014-01-01

    In this paper we study a random walk in a one-dimensional dynamic random environment consisting of a collection of independent particles performing simple symmetric random walks in a Poisson equilibrium with density ¿¿(0,8). At each step the random walk performs a nearest-neighbour jump, moving to

  11. Efficacy of a long-term secondary prevention programme following inpatient cardiovascular rehabilitation on risk and health-related quality of life in a low-education cohort: a randomized controlled study.

    Science.gov (United States)

    Mayer-Berger, Wolfgang; Simic, Dusan; Mahmoodzad, Jawad; Burtscher, Ralph; Kohlmeyer, Martin; Schwitalla, Birgitta; Redaèlli, Marcus

    2014-02-01

    The aim of this study was to evaluate the efficacy of a long-term secondary prevention programme following inpatient cardiovascular rehabilitation on cardiovascular risk and health-related quality of life in a cohort of middle-aged (≤58 years) coronary artery disease (CAD) patients of low educational level compared to usual care. The study included 600 patients with CAD, with 271 in the intervention group (IG) and 329 in the control group (CG). The average age was nearly 50 years in both groups, nearly 90% were male, and 77% had less than 10 years of school education. No significant differences existed between the groups at baseline. Both groups had a 3-week comprehensive cardiovascular inpatient rehabilitation programme at the beginning, the intervention consisted of one further rehabilitation session in hospital after 6 months and regular telephone reminders over a period of 36 months. Analyses were conducted on an intention-to-treat basis. To evaluate the individual risk level, we used the PROCAM score and intima-media thickness (IMT) was measured at the common carotid artery on both sides following international standards. Health-related quality of life was assessed with the EUROQOL and HADS. Patients in the IG showed better 3-year risk profile outcomes. The PROCAM score increased by 3.0 (IG) and by 3.7 (CG) from the beginning to after 3 years (p > 0.05 intention-to-treat). The average IMT increased by 0.04 mm in the CG and was reduced by 0.03 mm in the IG (p = 0.014 for the difference). The IG had a significant improvement in health-related quality of life. Mortality, myocardial infarction, and stroke were not different although 'other cardiac events' (cardiac surgery or intervention) were significantly lower in the IG than the CG patients (p quality of life between the IG and CG, despite the relatively positive outcomes in the CG. In this low-education (predominantly male), middle-aged cohort, the positive impact on cardiovascular risk was

  12. Copenhagen Airport Cohort

    DEFF Research Database (Denmark)

    Møller, Karina Lauenborg; Brauer, Charlotte; Mikkelsen, Sigurd

    2017-01-01

    PURPOSE: Copenhagen Airport Cohort 1990-2012 presents a unique data source for studies of health effects of occupational exposure to air pollution (ultrafine particles) and manual baggage handling among airport employees. We describe the extent of information in the cohort and in the follow...... covers 69 175 men in unskilled positions. The exposed cohort includes men in unskilled jobs employed at Copenhagen Airport in the period 1990-2012 either as baggage handlers or in other outdoor work. The reference cohort includes men in unskilled jobs working in the greater Copenhagen area. FINDINGS...... TO DATE: The cohort includes environmental Global Positioning System (GPS) measurements in Copenhagen Airport, information on job function/task for each calendar year of employment between 1990 and 2012, exposure to air pollution at residence, average weight of baggage lifted per day and lifestyle...

  13. Cohort profile: Ho Chi Minh City Youth Cohort--changes in diet, physical activity, sedentary behaviour and relationship with overweight/obesity in adolescents.

    Science.gov (United States)

    Trang, Nguyen Hoang Hanh Doan; Hong, Tang Kim; Dibley, Michael John

    2012-01-01

    The Ho Chi Minh Youth cohort study aimed to assess the change in nutritional status; indicators of adiposity; diet; physical activity and sedentary behaviours; home, neighbourhood and school microenvironments and their complex relationships in adolescents in urban areas of Ho Chi Minh City. Prospective 5-year cohort. Systematic random sampling was used to select 18 schools in urban districts. Children were followed up over 5 years with an assessment in each year. Consent, from both adolescents and their parents, was required. At baseline, 759 students were recruited into the cohort, and of these students, 740 remained in the cohort for the first round, 712 for the second round, 630 for the third round and 585 for the last round of follow-up. Anthropometric measurements were taken using established guidelines. Six main groups of exposure factors including dietary intake and behaviours, physical activity and sedentary behaviours, family social and physical environment, school environment, socioeconomic status and parental characteristics were measured. Retention rate was high (77%). Within 5-year period, the prevalence of combined overweight and obesity using International Obesity Task Force cut-off values increased from 14.2% to 21.8%. Time spent on physical activity decreased significantly in the 5-year period from 87 to 50 min/day. Time spent on sedentary behaviours increased in the 5-year period from 512 to 600 min/day. The complete data analysis of this cohort study will allow a full exploration of the role of environmental and lifestyle behaviours on adolescent overweight and obesity and also identify the factors most strongly associated with excess weight gain and the appearance of overweight and obesity in different age groups of adolescents from this large city in Vietnam.

  14. Randomized Comparison of Selective Internal Radiotherapy (SIRT) Versus Drug-Eluting Bead Transarterial Chemoembolization (DEB-TACE) for the Treatment of Hepatocellular Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Pitton, Michael B., E-mail: michael.pitton@unimedizin-mainz.de; Kloeckner, Roman [Johannes Gutenberg University Medical Center, Department of Diagnostic and Interventional Radiology (Germany); Ruckes, Christian [Johannes Gutenberg University Medical Center, IZKS (Germany); Wirth, Gesine M. [Johannes Gutenberg University Medical Center, Department of Diagnostic and Interventional Radiology (Germany); Eichhorn, Waltraud [Johannes Gutenberg University Medical Center, Department of Nuclear Medicine (Germany); Wörns, Marcus A.; Weinmann, Arndt [Johannes Gutenberg University Medical Center, Department of Internal Medicine (Germany); Schreckenberger, Mathias [Johannes Gutenberg University Medical Center, Department of Nuclear Medicine (Germany); Galle, Peter R. [Johannes Gutenberg University Medical Center, Department of Internal Medicine (Germany); Otto, Gerd [Johannes Gutenberg University Medical Center, Department of Transplantation Surgery (Germany); Dueber, Christoph [Johannes Gutenberg University Medical Center, Department of Diagnostic and Interventional Radiology (Germany)

    2015-04-15

    PurposeTo prospectively compare SIRT and DEB-TACE for treating hepatocellular carcinoma (HCC).MethodsFrom 04/2010–07/2012, 24 patients with histologically proven unresectable N0, M0 HCCs were randomized 1:1 to receive SIRT or DEB-TACE. SIRT could be repeated once in case of recurrence; while, TACE was repeated every 6 weeks until no viable tumor tissue was detected by MRI or contraindications prohibited further treatment. Patients were followed-up by MRI every 3 months; the final evaluation was 05/2013.ResultsBoth groups were comparable in demographics (SIRT: 8males/4females, mean age 72 ± 7 years; TACE: 10males/2females, mean age 71 ± 9 years), initial tumor load (1 patient ≥25 % in each group), and BCLC (Barcelona Clinic Liver Cancer) stage (SIRT: 12×B; TACE 1×A, 11×B). Median progression-free survival (PFS) was 180 days for SIRT versus 216 days for TACE patients (p = 0.6193) with a median TTP of 371 days versus 336 days, respectively (p = 0.5764). Median OS was 592 days for SIRT versus 788 days for TACE patients (p = 0.9271). Seven patients died in each group. Causes of death were liver failure (n = 4 SIRT group), tumor progression (n = 4 TACE group), cardiovascular events, and inconclusive (n = 1 in each group).ConclusionsNo significant differences were found in median PFS, OS, and TTP. The lower rate of tumor progression in the SIRT group was nullified by a greater incidence of liver failure. This pilot study is the first prospective randomized trial comparing SIRT and TACE for treating HCC, and results can be used for sample size calculations of future studies.

  15. Randomized Comparison of Selective Internal Radiotherapy (SIRT) Versus Drug-Eluting Bead Transarterial Chemoembolization (DEB-TACE) for the Treatment of Hepatocellular Carcinoma

    International Nuclear Information System (INIS)

    Pitton, Michael B.; Kloeckner, Roman; Ruckes, Christian; Wirth, Gesine M.; Eichhorn, Waltraud; Wörns, Marcus A.; Weinmann, Arndt; Schreckenberger, Mathias; Galle, Peter R.; Otto, Gerd; Dueber, Christoph

    2015-01-01

    PurposeTo prospectively compare SIRT and DEB-TACE for treating hepatocellular carcinoma (HCC).MethodsFrom 04/2010–07/2012, 24 patients with histologically proven unresectable N0, M0 HCCs were randomized 1:1 to receive SIRT or DEB-TACE. SIRT could be repeated once in case of recurrence; while, TACE was repeated every 6 weeks until no viable tumor tissue was detected by MRI or contraindications prohibited further treatment. Patients were followed-up by MRI every 3 months; the final evaluation was 05/2013.ResultsBoth groups were comparable in demographics (SIRT: 8males/4females, mean age 72 ± 7 years; TACE: 10males/2females, mean age 71 ± 9 years), initial tumor load (1 patient ≥25 % in each group), and BCLC (Barcelona Clinic Liver Cancer) stage (SIRT: 12×B; TACE 1×A, 11×B). Median progression-free survival (PFS) was 180 days for SIRT versus 216 days for TACE patients (p = 0.6193) with a median TTP of 371 days versus 336 days, respectively (p = 0.5764). Median OS was 592 days for SIRT versus 788 days for TACE patients (p = 0.9271). Seven patients died in each group. Causes of death were liver failure (n = 4 SIRT group), tumor progression (n = 4 TACE group), cardiovascular events, and inconclusive (n = 1 in each group).ConclusionsNo significant differences were found in median PFS, OS, and TTP. The lower rate of tumor progression in the SIRT group was nullified by a greater incidence of liver failure. This pilot study is the first prospective randomized trial comparing SIRT and TACE for treating HCC, and results can be used for sample size calculations of future studies

  16. Selection of peripheral intravenous catheters with 24-gauge side-holes versus those with 22-gauge end-hole for MDCT: A prospective randomized study

    Energy Technology Data Exchange (ETDEWEB)

    Tamura, Akio, E-mail: a.akahane@gmail.com [Department of Radiology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka 020-8505 (Japan); Kato, Kenichi, E-mail: kkato@iwate-med.ac.jp [Department of Radiology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka 020-8505 (Japan); Kamata, Masayoshi, E-mail: kamataaoi@yahoo.co.jp [Iwate Medical University Hospital, 19-1 Uchimaru, Morioka 020-8505 (Japan); Suzuki, Tomohiro, E-mail: suzukitomohiro123@gmail.com [Department of Radiology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka 020-8505 (Japan); Suzuki, Michiko, E-mail: mamimichiko@me.com [Department of Radiology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka 020-8505 (Japan); Nakayama, Manabu, E-mail: gakuymgt@yahoo.co.jp [Department of Radiology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka 020-8505 (Japan); Tomabechi, Makiko, E-mail: mtomabechi@mac.com [Department of Radiology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka 020-8505 (Japan); Nakasato, Tatsuhiko, E-mail: nakasato77@gmail.com [Department of Radiology, Southern Tohoku Research Institute for Neuroscience, 7-115 Yatsuyamada, Koriyama 963-8563 (Japan); Ehara, Shigeru, E-mail: ehara@iwate-med.ac.jp [Department of Radiology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka 020-8505 (Japan)

    2017-02-15

    Highlights: • We compared 24-gauge side-hole and conventional 22-gauge end-hole catheters in MDCT. • The 24-gauge side-hole catheter is noninferior to the 22-gauge end-hole catheter. • The 24-gauge side-hole catheter is safe and facilitates optimal enhancement quality. • The 24-gauge side-hole catheter is suitable for patients with narrow or fragile veins. - Abstract: Purpose: To compare the 24-gauge side-holes catheter and conventional 22-gauge end-hole catheter in terms of safety, injection pressure, and contrast enhancement on multi-detector computed tomography (MDCT). Materials & methods: In a randomized single-center study, 180 patients were randomized to either the 24-gauge side-holes catheter or the 22-gauge end-hole catheter groups. The primary endpoint was safety during intravenous administration of contrast material for MDCT, using a non-inferiority analysis (lower limit 95% CI greater than −10% non-inferiority margin for the group difference). The secondary endpoints were injection pressure and contrast enhancement. Results: A total of 174 patients were analyzed for safety during intravenous contrast material administration for MDCT. The overall extravasation rate was 1.1% (2/174 patients); 1 (1.2%) minor episode occurred in the 24-gauge side-holes catheter group and 1 (1.1%) in the 22-gauge end-hole catheter group (difference: 0.1%, 95% CI: −3.17% to 3.28%, non-inferiority P = 1). The mean maximum pressure was higher with the 24-gauge side-holes catheter than with the 22-gauge end-hole catheter (8.16 ± 0.95 kg/cm{sup 2} vs. 4.79 ± 0.63 kg/cm{sup 2}, P < 0.001). The mean contrast enhancement of the abdominal aorta, celiac artery, superior mesenteric artery, and pancreatic parenchyma in the two groups were not significantly different. Conclusion: In conclusion, our study showed that the 24-gauge side-holes catheter is safe and suitable for delivering iodine with a concentration of 300 mg/mL at a flow-rate of 3 mL/s, and it may contribute to

  17. Optimal dose selection accounting for patient subpopulations in a randomized Phase II trial to maximize the success probability of a subsequent Phase III trial.

    Science.gov (United States)

    Takahashi, Fumihiro; Morita, Satoshi

    2018-02-08

    Phase II clinical trials are conducted to determine the optimal dose of the study drug for use in Phase III clinical trials while also balancing efficacy and safety. In conducting these trials, it may be important to consider subpopulations of patients grouped by background factors such as drug metabolism and kidney and liver function. Determining the optimal dose, as well as maximizing the effectiveness of the study drug by analyzing patient subpopulations, requires a complex decision-making process. In extreme cases, drug development has to be terminated due to inadequate efficacy or severe toxicity. Such a decision may be based on a particular subpopulation. We propose a Bayesian utility approach (BUART) to randomized Phase II clinical trials which uses a first-order bivariate normal dynamic linear model for efficacy and safety in order to determine the optimal dose and study population in a subsequent Phase III clinical trial. We carried out a simulation study under a wide range of clinical scenarios to evaluate the performance of the proposed method in comparison with a conventional method separately analyzing efficacy and safety in each patient population. The proposed method showed more favorable operating characteristics in determining the optimal population and dose.

  18. Cohort Analysis of a 24-Week Randomized Controlled Trial to Assess the Efficacy of a Novel, Partial Meal Replacement Program Targeting Weight Loss and Risk Factor Reduction in Overweight/Obese Adults.

    Science.gov (United States)

    Brindal, Emily; Hendrie, Gilly A; Taylor, Pennie; Freyne, Jill; Noakes, Manny

    2016-05-04

    Our aim was to design and evaluate a weight-loss program, including a partial meal replacement program, point-of-care testing and face-to-face and smartphone app support, appropriate for delivery in a community pharmacy setting. Overweight or obese adults (n = 146, 71.2% female, 48.18 ± 11.75 years old) were recruited to participate in a 24-week weight loss study and randomised to two app conditions. The dietary intervention was consistent regardless of app. Twelve weeks of clinic appointments with a trained consultant were followed by only app support for an additional 12 weeks. By week 24, retention was 57.5%. There were no differences between app conditions. Based on a cohort analysis of the trial, the mean decrease in weight from baseline to week 24 was 6.43 ± 1.06 kg for males (p < 0.001) and 5.66 ± 0.70 kg for females (p < 0.001). Mixed models also revealed decreases for LDL Cholesterol (-0.13 ± 0.08 mmol/L, nonsignificant), triglycerides (-0.08 ± 0.05 mmol/L, nonsignificant) and an increase in HDL cholesterol (+0.08 ± 0.04 mmol/L, ns) were not significant by week 24. Blood glucose (-0.23 ± 0.08 mmol/L, p = 0.040) and blood pressure (Systolic blood pressure -5.77 ± 1.21 Hg/mm, p < 0.001) were significantly lower at week 24 compared to baseline. Weight loss self-efficacy increased and remained significantly higher than baseline at week 24 (16.85 ± 2.93, p < 0.001). Overall, the program supported participants and was successful in achieving significant weight loss and improvements in health outcomes over 24 weeks.

  19. Copenhagen Airport Cohort

    DEFF Research Database (Denmark)

    Møller, Karina Lauenborg; Brauer, Charlotte; Mikkelsen, Sigurd

    2017-01-01

    TO DATE: The cohort includes environmental Global Positioning System (GPS) measurements in Copenhagen Airport, information on job function/task for each calendar year of employment between 1990 and 2012, exposure to air pollution at residence, average weight of baggage lifted per day and lifestyle...... covers 69 175 men in unskilled positions. The exposed cohort includes men in unskilled jobs employed at Copenhagen Airport in the period 1990-2012 either as baggage handlers or in other outdoor work. The reference cohort includes men in unskilled jobs working in the greater Copenhagen area. FINDINGS...

  20. Random magnetism

    International Nuclear Information System (INIS)

    Tahir-Kheli, R.A.

    1975-01-01

    A few simple problems relating to random magnetic systems are presented. Translational symmetry, only on the macroscopic scale, is assumed for these systems. A random set of parameters, on the microscopic scale, for the various regions of these systems is also assumed. A probability distribution for randomness is obeyed. Knowledge of the form of these probability distributions, is assumed in all cases [pt

  1. Comparison between paricalcitol and active non-selective vitamin D receptor activator for secondary hyperparathyroidism in chronic kidney disease: a systematic review and meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Cai, Panpan; Tang, Xiaohong; Qin, Wei; Ji, Ling; Li, Zi

    2016-04-01

    The goal of this systematic review is to evaluate the efficacy and safety of paricalcitol versus active non-selective vitamin D receptor activators (VDRAs) for secondary hyperparathyroidism (SHPT) management in chronic kidney disease (CKD) patients. PubMed, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), clinicaltrials.gov (inception to September 2015), and ASN Web site were searched for relevant studies. A meta-analysis of randomized controlled trials (RCTs) and quasi-RCTs that assessed the effects and adverse events of paricalcitol and active non-selective VDRA in adult CKD patients with SHPT was performed using Review Manager 5.2. A total of 10 trials involving 734 patients were identified for this review. The quality of included trials was limited, and very few trials reported all-cause mortality or cardiovascular calcification without any differences between two groups. Compared with active non-selective VDRAs, paricalcitol showed no significant difference in both PTH reduction (MD -7.78, 95% CI -28.59-13.03, P = 0.46) and the proportion of patients who achieved the target reduction of PTH (OR 1.27, 95% CI 0.87-1.85, P = 0.22). In addition, no statistical differences were found in terms of serum calcium, episodes of hypercalcemia, serum phosphorus, calcium × phosphorus products, and bone metabolism index. Current evidence is insufficient, showing paricalcitol is superior to active non-selective VDRAs in lowering PTH or reducing the burden of mineral loading. Further trials are required to prove the tissue-selective effect of paricalcitol and to overcome the limitation of current research.

  2. Trigemino-gustatory interactions: a randomized controlled clinical trial assessing the effects of selective anesthesia of dental afferents on taste thresholds.

    Science.gov (United States)

    Lecor, Papa Abdou; Touré, Babacar; Boucher, Yves

    2018-03-01

    This study aimed at analyzing the effect of the temporary removal of trigeminal dental afferents on electrogustometric thresholds (EGMt). EGMt were measured in 300 healthy subjects randomized in three groups, in nine loci on the right and left side (RS, LS) of the tongue surface before and after anesthesia. Group IAN (n = 56 RS, n = 44 LS) received intraosseous local anesthesia of the inferior alveolar nerve (IAN). Group MdN received mandibular nerve (MdN) block targeting IAN before its entrance into the mandibular foramen (n = 60, RS, and n = 40, LS); group MxN receiving maxillary nerve (MxN) anesthesia (n = 56 RS and n = 44 LS) was the control group. Differences between mean EGMt were analyzed with the Wilcoxon test; correlation between type of anesthesia and EGMt was performed with Spearman's rho, all with a level of significance set at p ≤ 0.05. Significant EGMt (μA) differences before and after anesthesia were found in all loci with MdN and IAN on the ipsilateral side (p Anesthesia of the MdN was positively correlated with the increase in EGMt (p anesthesia of IAN was positively correlated only with the increase in EGMt measured at posterior and dorsal loci of the tongue surface (p anesthesia suggests a participation of dental afferents in taste perception. Extraction of teeth may impair food intake not only due to impaired masticatory ability but also to alteration of neurological trigemino-gustatory interactions. PACTR201602001452260.

  3. The Role of Preference on Outcomes of People Receiving Evidence-Informed Community Wound Care in Their Home or in a Nurse-Clinic Setting: A Cohort Study (n = 230)

    OpenAIRE

    Harrison, Margaret B.; VanDenKerkhof, Elizabeth G.; Hopman, Wilma M.; Carley, Meg E.

    2014-01-01

    This study followed a cohort of community-dwelling individuals receiving wound-care in a large urban-rural region. During a randomized control trial (RCT) evaluating outcomes of receiving care in a nurse-clinic or at home, many approached were willing to participate if they could choose their location of care. This provided a unique opportunity to enroll them as a “choice” cohort, following them in the same manner as the trial participants but allowing them to select their setting of care. Th...

  4. Shaping the ROTC Cohort

    National Research Council Canada - National Science Library

    Rittenhouse, Wiley P; Kwinn, Jr, Michael J

    2005-01-01

    ...) - to meet the future needs of the Army for commissioned officers. It is designed to shape each cohort to meet the Army's specific needs in terms of component, academic disciplines, race/ethnic makeup goals, gender, and targeted missions...

  5. Cancer Epidemiology Cohorts

    Science.gov (United States)

    Cohort studies are fundamental for epidemiological research by helping researchers better understand the etiology of cancer and provide insights into the key determinants of this disease and its outcomes.

  6. Long-Term Melatonin Therapy for Adolescents and Young Adults with Chronic Sleep Onset Insomnia and Late Melatonin Onset: Evaluation of Sleep Quality, Chronotype, and Lifestyle Factors Compared to Age-Related Randomly Selected Population Cohorts.

    Science.gov (United States)

    Zwart, Tom C; Smits, Marcel G; Egberts, Toine C G; Rademaker, Carin M A; van Geijlswijk, Ingeborg M

    2018-03-02

    The extent of continuance of melatonin therapy initiated in pre-pubertal children with chronic sleep onset insomnia (CSOI) was investigated in young adult life. Sleep timing, sleep quality, adverse events, reasons for cessation of therapy, and patient characteristics with regard to therapy regimen, chronotype and lifestyle factors possibly influencing sleeping behavior were assessed. With an online survey using questionnaires (Pittsburgh Sleep Quality Index, Insomnia Severity Index, Morningness-Eveningness Questionnaire, and Munich Chronotype Questionnaire), outcomes were measured and compared with age-related controls. These controls were extracted from published epidemiological research programs applying the same questionnaires. At the moment of the survey, melatonin was still continued by 27.3% of the patients, with a mean treatment duration of 10.8 years. The overall average treatment duration was 7.1 years. Sleep quality of both discontinued and persistent melatonin users did not deviate from controls. Sleep timing and chronotype scores indicated evening type preference in all responders. Adverse events were scarce but the perceived timing of pubertal development suggested a tendency towards delayed puberty in former and current users of melatonin. This study may underestimate the number of children that are able to stop using melatonin due to the response rate (47.8%) and appeal for continuing users. Sleep timing parameters were based on self-reported estimates. Control populations were predominantly students and were of varying nationalities. The statistical power of this study is low due to the limited sample size. Melatonin therapy sustained for 7.1 years does not result in substantial deviations of sleep quality as compared to controls and appears to be safe. The evening type preference suggests a causal relation with CSOI. This study shows that ten years after initiation of treatment with melatonin for CSOI, approximately 75% of the patients will have normal sleep quality without medication.

  7. Long-Term Melatonin Therapy for Adolescents and Young Adults with Chronic Sleep Onset Insomnia and Late Melatonin Onset : Evaluation of Sleep Quality, Chronotype, and Lifestyle Factors Compared to Age-Related Randomly Selected Population Cohorts

    NARCIS (Netherlands)

    Zwart, Tom; Smits, Marcel G; Egberts, Toine C G; Rademaker, Carin M A; van Geijlswijk, Ingeborg M

    2018-01-01

    The extent of continuance of melatonin therapy initiated in pre-pubertal children with chronic sleep onset insomnia (CSOI) was investigated in young adult life. Sleep timing, sleep quality, adverse events, reasons for cessation of therapy, and patient characteristics with regard to therapy regimen,

  8. The selective beta 1-blocking agent metoprolol compared with antithyroid drug and thyroxine as preoperative treatment of patients with hyperthyroidism. Results from a prospective, randomized study.

    Science.gov (United States)

    Adlerberth, A; Stenström, G; Hasselgren, P O

    1987-01-01

    Despite the increasing use of beta-blocking agents alone as preoperative treatment of patients with hyperthyroidism, there are no controlled clinical studies in which this regimen has been compared with a more conventional preoperative treatment. Thirty patients with newly diagnosed and untreated hyperthyroidism were randomized to preoperative treatment with methimazole in combination with thyroxine (Group I) or the beta 1-blocking agent metoprolol (Group II). Metoprolol was used since it has been demonstrated that the beneficial effect of beta-blockade in hyperthyroidism is mainly due to beta 1-blockade. The preoperative, intraoperative, and postoperative courses in the two groups were compared, and patients were followed up for 1 year after thyroidectomy. At the time of diagnosis, serum concentration of triiodothyronine (T3) was 6.1 +/- 0.59 nmol/L in Group I and 5.7 +/- 0.66 nmol/L in Group II (reference interval 1.5-3.0 nmol/L). Clinical improvement during preoperative treatment was similar in the two groups of patients, but serum T3 was normalized only in Group I. The median length of preoperative treatment was 12 weeks in Group I and 5 weeks in Group II (p less than 0.01). There were no serious adverse effects of the drugs during preoperative preparation in either treatment group. Operating time, consistency and vascularity of the thyroid gland, and intraoperative blood loss were similar in the two groups. No anesthesiologic or cardiovascular complications occurred during operation in either group. One patient in Group I (7%) and three patients in Group II (20%) had clinical signs of hyperthyroid function during the first postoperative day. These symptoms were abolished by the administration of small doses of metoprolol, and no case of thyroid storm occurred. Postoperative hypocalcemia or recurrent laryngeal nerve paralysis did not occur in either group. During the first postoperative year, hypothyroidism developed in two patients in Group I (13%) and in six

  9. Promoting mobility after hip fracture (ProMo: study protocol and selected baseline results of a year-long randomized controlled trial among community-dwelling older people

    Directory of Open Access Journals (Sweden)

    Sipilä Sarianna

    2011-12-01

    Full Text Available Abstract Background To cope at their homes, community-dwelling older people surviving a hip fracture need a sufficient amount of functional ability and mobility. There is a lack of evidence on the best practices supporting recovery after hip fracture. The purpose of this article is to describe the design, intervention and demographic baseline results of a study investigating the effects of a rehabilitation program aiming to restore mobility and functional capacity among community-dwelling participants after hip fracture. Methods/Design Population-based sample of over 60-year-old community-dwelling men and women operated for hip fracture (n = 81, mean age 79 years, 78% were women participated in this study and were randomly allocated into control (Standard Care and ProMo intervention groups on average 10 weeks post fracture and 6 weeks after discharged to home. Standard Care included written home exercise program with 5-7 exercises for lower limbs. Of all participants, 12 got a referral to physiotherapy. After discharged to home, only 50% adhered to Standard Care. None of the participants were followed-up for Standard Care or mobility recovery. ProMo-intervention included Standard Care and a year-long program including evaluation/modification of environmental hazards, guidance for safe walking, pain management, progressive home exercise program and physical activity counseling. Measurements included a comprehensive battery of laboratory tests and self-report on mobility limitation, disability, physical functional capacity and health as well as assessments for the key prerequisites for mobility, disability and functional capacity. All assessments were performed blinded at the research laboratory. No significant differences were observed between intervention and control groups in any of the demographic variables. Discussion Ten weeks post hip fracture only half of the participants were compliant to Standard Care. No follow-up for Standard Care or

  10. 1970 British Cohort Study

    Directory of Open Access Journals (Sweden)

    Matt Brown

    2014-10-01

    Full Text Available The 1970 British Cohort Study (BCS70 is one of Britain’s world famous national longitudinal birth cohort studies, three of which are run by the Centre for Longitudinal Studies at the Institute of Education, University of London.  BCS70 follows the lives of more than 17,000 people born in England, Scotland and Wales in a single week of 1970. Over the course of cohort members lives, the BCS70 has collected information on health, physical, educational and social development, and economic circumstances among other factors. Since the birth survey in 1970, there have been nine ‘sweeps’ of all cohort members at ages 5, 10, 16, 26, 30, 34, 38 and most recently at 42. Data has been collected from a number of different sources (the midwife present at birth, parents of the cohort members, head and class teachers, school health service personnel and the cohort members themselves. The data has been collected in a variety of ways including via paper and electronic questionnaires, clinical records, medical examinations, physical measurements, tests of ability, educational assessments and diaries. The majority of BCS70 survey data can be accessed by bona fide researchers through the UK Data Service at the University of Essex.

  11. Randomized random walk on a random walk

    International Nuclear Information System (INIS)

    Lee, P.A.

    1983-06-01

    This paper discusses generalizations of the model introduced by Kehr and Kunter of the random walk of a particle on a one-dimensional chain which in turn has been constructed by a random walk procedure. The superimposed random walk is randomised in time according to the occurrences of a stochastic point process. The probability of finding the particle in a particular position at a certain instant is obtained explicitly in the transform domain. It is found that the asymptotic behaviour for large time of the mean-square displacement of the particle depends critically on the assumed structure of the basic random walk, giving a diffusion-like term for an asymmetric walk or a square root law if the walk is symmetric. Many results are obtained in closed form for the Poisson process case, and these agree with those given previously by Kehr and Kunter. (author)

  12. Selective mutism.

    Science.gov (United States)

    Hua, Alexandra; Major, Nili

    2016-02-01

    Selective mutism is a disorder in which an individual fails to speak in certain social situations though speaks normally in other settings. Most commonly, this disorder initially manifests when children fail to speak in school. Selective mutism results in significant social and academic impairment in those affected by it. This review will summarize the current understanding of selective mutism with regard to diagnosis, epidemiology, cause, prognosis, and treatment. Studies over the past 20 years have consistently demonstrated a strong relationship between selective mutism and anxiety, most notably social phobia. These findings have led to the recent reclassification of selective mutism as an anxiety disorder in the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition. In addition to anxiety, several other factors have been implicated in the development of selective mutism, including communication delays and immigration/bilingualism, adding to the complexity of the disorder. In the past few years, several randomized studies have supported the efficacy of psychosocial interventions based on a graduated exposure to situations requiring verbal communication. Less data are available regarding the use of pharmacologic treatment, though there are some studies that suggest a potential benefit. Selective mutism is a disorder that typically emerges in early childhood and is currently conceptualized as an anxiety disorder. The development of selective mutism appears to result from the interplay of a variety of genetic, temperamental, environmental, and developmental factors. Although little has been published about selective mutism in the general pediatric literature, pediatric clinicians are in a position to play an important role in the early diagnosis and treatment of this debilitating condition.

  13. Selective enhancement of Selényi rings induced by the cross-correlation between the interfaces of a two-dimensional randomly rough dielectric film

    Science.gov (United States)

    Banon, J.-P.; Hetland, Ø. S.; Simonsen, I.

    2018-02-01

    By the use of both perturbative and non-perturbative solutions of the reduced Rayleigh equation, we present a detailed study of the scattering of light from two-dimensional weakly rough dielectric films. It is shown that for several rough film configurations, Selényi interference rings exist in the diffusely scattered light. For film systems supported by dielectric substrates where only one of the two interfaces of the film is weakly rough and the other planar, Selényi interference rings are observed at angular positions that can be determined from simple phase arguments. For such single-rough-interface films, we find and explain by a single scattering model that the contrast in the interference patterns is better when the top interface of the film (the interface facing the incident light) is rough than when the bottom interface is rough. When both film interfaces are rough, Selényi interference rings exist but a potential cross-correlation of the two rough interfaces of the film can be used to selectively enhance some of the interference rings while others are attenuated and might even disappear. This feature may in principle be used in determining the correlation properties of interfaces of films that otherwise would be difficult to access.

  14. Drop-out from cardiovascular magnetic resonance in a randomized controlled trial of ST-elevation myocardial infarction does not cause selection bias on endpoints

    DEFF Research Database (Denmark)

    Laursen, Peter Nørkjær; Holmvang, L.; Kelbæk, H.

    2017-01-01

    Background: The extent of selection bias due to drop-out in clinical trials of ST-elevation myocardial infarction (STEMI) using cardiovascular magnetic resonance (CMR) as surrogate endpoints is unknown. We sought to interrogate the characteristics and prognosis of patients who dropped out before...... years of follow-up were assessed and compared between CMR-drop-outs and CMR-participants using the trial screening log and the Eastern Danish Heart Registry. Results: The drop-out rate from acute CMR was 28% (n = 92). These patients had a significantly worse clinical risk profile upon admission...... as evaluated by the TIMI-risk score (3.7 (± 2.1) vs 4.0 (± 2.6), p = 0.043) and by left ventricular ejection fraction (43 (± 9) vs. 47 (± 10), p = 0.029). CMR drop-outs had a higher incidence of known hypertension (39% vs. 35%, p = 0.043), known diabetes (14% vs. 7%, p = 0.025), known cardiac disease (11% vs...

  15. Indirect language therapy for children with persistent language impairment in mainstream primary schools: outcomes from a cohort intervention.

    Science.gov (United States)

    McCartney, Elspeth; Boyle, James; Ellis, Sue; Bannatyne, Susan; Turnbull, Mary

    2011-01-01

    A manualized language therapy developed via a randomized controlled trial had proved efficacious in the short-term in developing expressive language for mainstream primary school children with persistent language impairment. This therapy had been delivered to a predetermined schedule by speech and language therapists or speech and language therapy assistants to children individually or in groups. However, this model of service delivery is no longer the most common model in UK schools, where indirect consultancy approaches with intervention delivered by school staff are often used. A cohort study was undertaken to investigate whether the therapy was equally efficacious when delivered to comparable children by school staff, rather than speech and language therapists or speech and language therapy assistants. Children in the cohort study were selected using the same criteria as in the randomized controlled trial, and the same manualized therapy was used, but delivered by mainstream school staff using a consultancy model common in the UK. Outcomes were compared with those of randomized controlled trial participants. The gains in expressive language measured in the randomized controlled trial were not replicated in the cohort study. Less language-learning activity was recorded than had been planned, and less than was delivered in the randomized controlled trial. Implications for 'consultancy' speech and language therapist service delivery models in mainstream schools are outlined. At present, the more efficacious therapy is that delivered by speech and language therapists or speech and language therapy assistants to children individually or in groups. This may be related to more faithful adherence to the interventions schedule, and to a probably greater amount of language-learning activity undertaken. Intervention delivered via school-based 'consultancy' approaches in schools will require to be carefully monitored by schools and SLT services. © 2010 Royal College of

  16. Dynamic models for estimating the effect of HAART on CD4 in observational studies: Application to the Aquitaine Cohort and the Swiss HIV Cohort Study.

    Science.gov (United States)

    Prague, Mélanie; Commenges, Daniel; Gran, Jon Michael; Ledergerber, Bruno; Young, Jim; Furrer, Hansjakob; Thiébaut, Rodolphe

    2017-03-01

    Highly active antiretroviral therapy (HAART) has proved efficient in increasing CD4 counts in many randomized clinical trials. Because randomized trials have some limitations (e.g., short duration, highly selected subjects), it is interesting to assess the effect of treatments using observational studies. This is challenging because treatment is started preferentially in subjects with severe conditions. This general problem had been treated using Marginal Structural Models (MSM) relying on the counterfactual formulation. Another approach to causality is based on dynamical models. We present three discrete-time dynamic models based on linear increments models (LIM): the first one based on one difference equation for CD4 counts, the second with an equilibrium point, and the third based on a system of two difference equations, which allows jointly modeling CD4 counts and viral load. We also consider continuous-time models based on ordinary differential equations with non-linear mixed effects (ODE-NLME). These mechanistic models allow incorporating biological knowledge when available, which leads to increased statistical evidence for detecting treatment effect. Because inference in ODE-NLME is numerically challenging and requires specific methods and softwares, LIM are a valuable intermediary option in terms of consistency, precision, and complexity. We compare the different approaches in simulation and in illustration on the ANRS CO3 Aquitaine Cohort and the Swiss HIV Cohort Study. © 2016, The International Biometric Society.

  17. Use of selective serotonin reuptake inhibitors and risk of re-operation due to post-surgical bleeding in breast cancer patients: a Danish population-based cohort study

    DEFF Research Database (Denmark)

    Gärtner, Rune; Cronin-Fenton, Deirdre; Hundborg, Heidi Holmager

    2010-01-01

    Selective serotonin reuptake inhibitors (SSRI) decrease platelet-function, which suggests that SSRI use may increase the risk of post-surgical bleeding. Few studies have investigated this potential association.......Selective serotonin reuptake inhibitors (SSRI) decrease platelet-function, which suggests that SSRI use may increase the risk of post-surgical bleeding. Few studies have investigated this potential association....

  18. The design and protocol of heat-sensitive moxibustion for knee osteoarthritis: a multicenter randomized controlled trial on the rules of selecting moxibustion location

    Directory of Open Access Journals (Sweden)

    Chi Zhenhai

    2010-06-01

    Full Text Available Abstract Background Knee osteoarthritis is a major cause of pain and functional limitation. Complementary and alternative medical approaches have been employed to relieve symptoms and to avoid the side effects of conventional medication. Moxibustion has been widely used to treat patients with knee osteoarthritis. Our past researches suggested heat-sensitive moxibustion might be superior to the conventional moxibustion. Our objective is to investigate the effectiveness of heat-sensitive moxibustion compared with conventional moxibustion or conventional drug treatment. Methods This study consists of a multi-centre (four centers in China, randomised, controlled trial with three parallel arms (A: heat-sensitive moxibustion; B: conventional moxibustion; C: conventional drug group. The moxibustion locations are different from A and B. Group A selects heat-sensitization acupoint from the region consisting of Yin Lingquan(SP9, Yang Lingquan(GB34, Liang Qiu(ST34, and Xue Hai (SP10. Meanwhile, fixed acupoints are used in group B, that is Xi Yan (EX-LE5 and He Ding (EX-LE2. The conventional drug group treats with intra-articular Sodium Hyaluronate injection. The outcome measures above will be assessed before the treatment, the 30 days of the last moxibustion session and 6 months after the last moxibustion session. Discussion This trial will utilize high quality trial methodologies in accordance with CONSORT guidelines. It will provide evidence for the effectiveness of moxibustion as a treatment for moderate and severe knee osteoarthritis. Moreover, the result will clarify the rules of heat-sensitive moxibustion location to improve the therapeutic effect with suspended moxibustion, and propose a new concept and a new theory of moxibustion to guide clinical practices. Trial Registration The trial is registered at Controlled Clinical Trials: ChiCTR-TRC-00000600.

  19. Primary Sjogren's syndrome and the risk of acute pancreatitis: a nationwide cohort study.

    Science.gov (United States)

    Chang, Chi-Ching; Chang, Yu-Sheng; Wang, Shu-Hung; Lin, Shyr-Yi; Chen, Yi-Hsuan; Chen, Jin Hua

    2017-08-11

    Studies on the risk of acute pancreatitis in patients with primary Sjogren's syndrome (pSS) are limited. We evaluated the effects of pSS on the risk of acute pancreatitis in a nationwide, population-based cohort in Taiwan. Population-based retrospective cohort study. We studied the claims data of the >97% Taiwan population from 2002 to 2012. We identified 9468 patients with pSS by using the catastrophic illness registry of the National Health Insurance Database in Taiwan. We also selected 37 872 controls that were randomly frequency matched by age (in 5 year bands), sex and index year from the general population. We analysed the risk of acute pancreatitis by using Cox proportional hazards regression models including sex, age and comorbidities. From 23.74 million people in the cohort, 9468 patients with pSS (87% women, mean age=55.6 years) and 37 872 controls were followed-up for 4.64 and 4.74 years, respectively. A total of 44 cases of acute pancreatitis were identified in the pSS cohort versus 105 cases in the non-pSS cohort. Multivariate Cox regression analysis indicated that the incidence rate of acute pancreatitis was significantly higher in the pSS cohort than in the non-pSS cohort (adjusted HR (aHR) 1.48, 95% CI 1.03 to 2.12). Cyclophosphamide use increased the risk of acute pancreatitis (aHR 5.27, 95% CI 1.16 to 23.86). By contrast, hydroxychloroquine reduced the risk of acute pancreatitis (aHR 0.23, 95% CI 0.09 to 0.55). This nationwide, retrospective cohort study demonstrated that the risk of acute pancreatitis was significantly higher in patients with pSS than in the general population. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  20. Risk of Nephrotic Syndrome following Enteroviral Infection in Children: A Nationwide Retrospective Cohort Study.

    Science.gov (United States)

    Lin, Jiun-Nong; Lin, Cheng-Li; Yang, Chi-Hui; Lin, Ming-Chia; Lai, Chung-Hsu; Lin, Hsi-Hsun; Kao, Chia-Hung

    2016-01-01

    Nephrotic syndrome is a common chronic illness encountered during childhood. Infections have been identified as a cause of nephrotic syndrome. The aim of this study was to evaluate the association between enteroviral infection and nephrotic syndrome. A nationwide retrospective cohort study was conducted by analyzing data from the National Health Insurance Research Database in Taiwan. Children aged children were randomly selected as the comparison cohort. The primary endpoint was the occurrence of nephrotic syndrome. This study included 280,087 enterovirus-infected children and 280,085 non-enterovirus-infected children. The mean age of the enterovirus-infected children was 2.38 years, and 53.7% of these children were boys. The overall incidence densities of nephrotic syndrome for enterovirus- and non-enterovirus-infected children were 2.65 and 2.21 per 10,000 person-years, respectively. The enterovirus-infected cohort had a higher cumulative incidence of nephrotic syndrome than did the non-enterovirus-infected cohort (log-rank test, p = 0.01). Multivariable analyses revealed that children with enteroviral infection were significantly associated with an increased risk of nephrotic syndrome compared with those without enteroviral infection (adjusted hazard ratio, 1.20; 95% confidence interval, 1.04-1.39; p = 0.01), particularly in children infected with coxsackievirus. Subgroup analyses revealed that enterovirus-infected girls, children of blue-collar workers, and children without allergies had a higher risk of nephrotic syndrome than did children in the non-enterovirus-infected cohort. This study revealed a significant association between enteroviral infection and nephrotic syndrome. Additional studies elucidating the role and pathogenesis of enterovirus in nephrotic syndrome are warranted.

  1. Effects on heart function of neoadjuvant chemotherapy and chemoradiotherapy in patients with cancer in the esophagus or gastroesophageal junction – a prospective cohort pilot study within a randomized clinical trial

    International Nuclear Information System (INIS)

    Lund, Mikael; Alexandersson von Döbeln, Gabriella; Nilsson, Magnus; Winter, Reidar; Lundell, Lars; Tsai, Jon A; Kalman, Sigridur

    2015-01-01

    Neoadjuvant therapy for cancer of the esophagus or gastroesophageal (GE)-junction is well established. The pros and cons of chemoradiotherapy and chemotherapy are debated. Chemoradiotherapy might impair cardiac function eliciting postoperative morbidity. The aim of this pilot study was to describe acute changes in left ventricular function following chemoradiotherapy or chemotherapy. Patients with esophageal and (GE)-junction cancer enrolled at our center into a multicenter trial comparing neoadjuvant chemoradiotherapy and chemotherapy were eligible. Patients were randomized to receive cisplatin and 5-fluorouracil with or without the addition of 40 Gy radiotherapy prior to surgery. Left ventricular function was evaluated using echocardiography and plasma N-Terminal Pro-B-Type Natriuretic Peptide (NT-proBNP) before and after neoadjuvant treatment. The primary outcome measure was left ventricular global strain (GS). Clinical effects were assessed using repeated exercise tests. Linear mixed models were used to analyze the effects of treatment group, and the interaction between groups. 40 patients participated (chemoradiotherapy, n = 17; chemotherapy, n = 23). In the chemoradiotherapy group there was no change in left ventricular global strain but mitral annular plane systolic excursion (MAPSE) of the ventricular septum, early diastolic filling velocity (E-velocity), and the ratio of early to late ventricular filling velocities (E/A ratio) decreased significantly (p = 0.02, p = 0.01, and p = 0.03, respectively). No changes were observed in the chemotherapy group. There was a trend towards an interaction effect for MAPSE sept and E (p = 0.09 and p = 0.09). NT-proBNP increased following chemoradiotherapy (p = 0.05) but not after chemotherapy (p > 0.99), and there was a trend towards an interaction effect (p = 0.07). Working capacity decreased following neoadjuvant treatment (chemoradiotherapy p = 0.001, chemotherapy p = 0.03) and was more pronounced after

  2. The Transeurope Footrace Project: longitudinal data acquisition in a cluster randomized mobile MRI observational cohort study on 44 endurance runners at a 64-stage 4,486km transcontinental ultramarathon

    Directory of Open Access Journals (Sweden)

    Schütz Uwe HW

    2012-07-01

    Full Text Available Abstract Background The TransEurope FootRace 2009 (TEFR09 was one of the longest transcontinental ultramarathons with an extreme endurance physical load of running nearly 4,500 km in 64 days. The aim of this study was to assess the wide spectrum of adaptive responses in humans regarding the different tissues, organs and functional systems being exposed to such chronic physical endurance load with limited time for regeneration and resulting negative energy balance. A detailed description of the TEFR project and its implemented measuring methods in relation to the hypotheses are presented. Methods The most important research tool was a 1.5 Tesla magnetic resonance imaging (MRI scanner mounted on a mobile unit following the ultra runners from stage to stage each day. Forty-four study volunteers (67% of the participants were cluster randomized into two groups for MRI measurements (22 subjects each according to the project protocol with its different research modules: musculoskeletal system, brain and pain perception, cardiovascular system, body composition, and oxidative stress and inflammation. Complementary to the diverse daily mobile MR-measurements on different topics (muscle and joint MRI, T2*-mapping of cartilage, MR-spectroscopy of muscles, functional MRI of the brain, cardiac and vascular cine MRI, whole body MRI other methods were also used: ice-water pain test, psychometric questionnaires, bioelectrical impedance analysis (BIA, skinfold thickness and limb circumference measurements, daily urine samples, periodic blood samples and electrocardiograms (ECG. Results Thirty volunteers (68% reached the finish line at North Cape. The mean total race speed was 8.35 km/hour. Finishers invested 552 hours in total. The completion rate for planned MRI investigations was more than 95%: 741 MR-examinations with 2,637 MRI sequences (more than 200,000 picture data, 5,720 urine samples, 244 blood samples, 205 ECG, 1,018 BIA, 539 anthropological

  3. Maternal vitamin D supplementation during pregnancy and lactation to prevent acute respiratory infections in infancy in Dhaka, Bangladesh (MDARI trial): protocol for a prospective cohort study nested within a randomized controlled trial.

    Science.gov (United States)

    Morris, Shaun K; Pell, Lisa G; Rahman, Mohammed Ziaur; Dimitris, Michelle C; Mahmud, Abdullah; Islam, M Munirul; Ahmed, Tahmeed; Pullenayegum, Eleanor; Kashem, Tahmid; Shanta, Shaila S; Gubbay, Jonathan; Papp, Eszter; Science, Michelle; Zlotkin, Stanley; Roth, Daniel E

    2016-10-13

    Early infancy is a high-risk period for severe acute respiratory infection (ARI), particularly in low-income countries with resource-limited health systems. Lower respiratory tract infection (LRTI) is commonly preceded by upper respiratory infection (URTI), and often caused by respiratory syncytial virus (RSV), influenza and other common community-acquired viral pathogens. Vitamin D status is a candidate modifiable early-life determinant of the host antiviral immune response and thus may influence the risk of ARI-associated morbidity in high-risk populations. In the Maternal Vitamin D for Infant Growth (MDIG) study in Dhaka, Bangladesh (NCT01924013), 1300 pregnant women are randomized to one of five groups: placebo, 4200 IU/week, 16,800 IU/week, or 28,000 IU/week from 2 nd trimester to delivery plus placebo from 0-6 months postpartum; or, 28,000 IU/week prenatal and until 6-months postpartum. In the Maternal Vitamin D for ARI in Infancy (MDARI) sub-study nested within the MDIG trial, trained personnel conduct weekly postnatal home visits to inquire about ARI symptoms and conduct a standardized clinical assessment. Supplementary home visits between surveillance visits are conducted when caregivers make phone notifications of new infant symptoms. Mid-turbinate nasal swab samples are obtained from infants who meet standardized clinical ARI criteria. Specimens are tested by polymerase chain reaction (PCR) for 8 viruses (influenza A/B, parainfluenza 1/2/3, RSV, adenovirus, and human metapneumovirus), and nasal carriage density of Streptococcus pneumoniae. The primary outcome is the incidence rate of microbiologically-positive viral ARI, using incidence rate ratios to estimate between-group differences. We hypothesize that among infants 0-6 months of age, the incidence of microbiologically-confirmed viral ARI will be significantly lower in infants whose mothers received high-dose prenatal/postpartum vitamin D supplements versus placebo. Secondary outcomes include

  4. A shared frailty model for case-cohort samples: parent and offspring relations in an adoption study

    DEFF Research Database (Denmark)

    Petersen, Liselotte; Sørensen, Thorkild I A; Andersen, Per Kragh

    2010-01-01

    of their biological and adoptive parents were collected with the purpose of studying the association of survival between the adoptee and his/her biological or adoptive parents. Motivated by this study, we explored how to make inference in a shared frailty model for case-cohort data. Our approach was to use inverse......The Danish adoption register contains data on the 12 301 Danish nonfamilial adoptions during 1924-1947. From that register a case-cohort sample was selected consisting of all case adoptees, that is those adoptees dying before age 70 years, and a random sample of 1683 adoptees. The survival data...... probability weighting to account for the sampling in a conditional, shared frailty Poisson model and to use the robust variance estimator proposed by Moger et al. (Statist. Med. 2008; 27:1062-1074).To explore the performance of the estimation procedure, a simulation study was conducted. We studied situations...

  5. Bayesian Age-Period-Cohort Modeling and Prediction - BAMP

    Directory of Open Access Journals (Sweden)

    Volker J. Schmid

    2007-10-01

    Full Text Available The software package BAMP provides a method of analyzing incidence or mortality data on the Lexis diagram, using a Bayesian version of an age-period-cohort model. A hierarchical model is assumed with a binomial model in the first-stage. As smoothing priors for the age, period and cohort parameters random walks of first and second order, with and without an additional unstructured component are available. Unstructured heterogeneity can also be included in the model. In order to evaluate the model fit, posterior deviance, DIC and predictive deviances are computed. By projecting the random walk prior into the future, future death rates can be predicted.

  6. Random Fields

    Science.gov (United States)

    Vanmarcke, Erik

    1983-03-01

    Random variation over space and time is one of the few attributes that might safely be predicted as characterizing almost any given complex system. Random fields or "distributed disorder systems" confront astronomers, physicists, geologists, meteorologists, biologists, and other natural scientists. They appear in the artifacts developed by electrical, mechanical, civil, and other engineers. They even underlie the processes of social and economic change. The purpose of this book is to bring together existing and new methodologies of random field theory and indicate how they can be applied to these diverse areas where a "deterministic treatment is inefficient and conventional statistics insufficient." Many new results and methods are included. After outlining the extent and characteristics of the random field approach, the book reviews the classical theory of multidimensional random processes and introduces basic probability concepts and methods in the random field context. It next gives a concise amount of the second-order analysis of homogeneous random fields, in both the space-time domain and the wave number-frequency domain. This is followed by a chapter on spectral moments and related measures of disorder and on level excursions and extremes of Gaussian and related random fields. After developing a new framework of analysis based on local averages of one-, two-, and n-dimensional processes, the book concludes with a chapter discussing ramifications in the important areas of estimation, prediction, and control. The mathematical prerequisite has been held to basic college-level calculus.

  7. Risk of Periodontal Disease in Patients With Asthma: A Nationwide Population-Based Retrospective Cohort Study.

    Science.gov (United States)

    Shen, Te-Chun; Chang, Pei-Ying; Lin, Cheng-Li; Wei, Chang-Ching; Tu, Chih-Yen; Hsia, Te-Chun; Shih, Chuen-Ming; Hsu, Wu-Huei; Sung, Fung-Chang; Kao, Chia-Hung

    2017-08-01

    Studies have reported an association between asthma and oral diseases, including periodontal diseases. The aim of this retrospective study is to investigate risk of periodontal diseases for patients with asthma. Using the claims data of National Health Insurance of Taiwan and patients without a history of periodontal diseases, 19,206 asthmatic patients, who were newly diagnosed from 2000 through 2010, were identified. For each case, four comparison individuals without history of asthma and periodontal disease were randomly selected from the general population and frequency matched (categorical matched) by sex, age, and year of diagnosis (n = 76,824). Both cohorts were followed to the end of 2011 to monitor occurrence of periodontal diseases. Adjusted hazard ratios (aHRs) of periodontal disease were estimated using Cox proportional hazards regression analysis. Overall incidence of periodontal diseases was 1.18-fold greater in the asthma cohort than in the comparison cohort (P periodontal diseases compared with those with a mean of less than one visit. Patients with at least three admissions annually also had a similar aHR (51.8) for periodontal disease. In addition, asthmatic patients on inhaled corticosteroid (ICS) therapy had greater aHRs than non-users (aHR = 1.12; 95% CI = 1.03 to 1.23). In the studied population, asthmatic patients are at an elevated risk of developing periodontal diseases. The risk is much greater for those with emergency medical demands or hospital admissions and those on ICS treatment.

  8. Commentary: considerations for using the 'Trials within Cohorts' design in a clinical trial of an investigational medicinal product.

    Science.gov (United States)

    Bibby, Anna C; Torgerson, David J; Leach, Samantha; Lewis-White, Helen; Maskell, Nick A

    2018-01-08

    The 'trials within cohorts' (TwiC) design is a pragmatic approach to randomised trials in which trial participants are randomly selected from an existing cohort. The design has multiple potential benefits, including the option of conducting multiple trials within the same cohort. To date, the TwiC design methodology been used in numerous clinical settings but has never been applied to a clinical trial of an investigational medicinal product (CTIMP). We have recently secured the necessary approvals to undertake the first CTIMP using the TwiC design. In this paper, we describe some of the considerations and modifications required to ensure such a trial is compliant with Good Clinical Practice and international clinical trials regulations. We advocate using a two-stage consent process and using the consent stages to explicitly differentiate between trial participants and cohort participants who are providing control data. This distinction ensured compliance but had consequences with respect to costings, recruitment and the trial assessment schedule. We have demonstrated that it is possible to secure ethical and regulatory approval for a CTIMP TwiC. By including certain considerations at the trial design stage, we believe this pragmatic and efficient methodology could be utilised in other CTIMPs in future.

  9. Secure Path Selection under Random Fading

    Directory of Open Access Journals (Sweden)

    Furqan Jameel

    2017-05-01

    Full Text Available Application-oriented Wireless Sensor Networks (WSNs promises to be one of the most useful technologies of this century. However, secure communication between nodes in WSNs is still an unresolved issue. In this context, we propose two protocols (i.e. Optimal Secure Path (OSP and Sub-optimal Secure Path (SSP to minimize the outage probability of secrecy capacity in the presence of multiple eavesdroppers. We consider dissimilar fading at the main and wiretap link and provide detailed evaluation of the impact of Nakagami-m and Rician-K factors on the secrecy performance of WSNs. Extensive simulations are performed to validate our findings. Although the optimal scheme ensures more security, yet the sub-optimal scheme proves to be a more practical approach to secure wireless links.

  10. Nested Cohort - R software package

    Science.gov (United States)

    NestedCohort is an R software package for fitting Kaplan-Meier and Cox Models to estimate standardized survival and attributable risks for studies where covariates of interest are observed on only a sample of the cohort.

  11. International Childhood Cancer Cohort Consortium

    Science.gov (United States)

    An alliance of several large-scale prospective cohort studies of children to pool data and biospecimens from individual cohorts to study various modifiable and genetic factors in relation to cancer risk

  12. [Scrotal temperature in 258 healthy men, randomly selected from a population of men aged 18 to 23 years old. Statistical analysis, epidemiologic observations, and measurement of the testicular diameters].

    Science.gov (United States)

    Valeri, A; Mianné, D; Merouze, F; Bujan, L; Altobelli, A; Masson, J

    1993-06-01

    Scrotal hyperthermia can induce certain alterations in spermatogenesis. The basal scrotal temperature used to define hyperthermia is usually 33 degrees C. However, no study, conducted according to a strict methodology has validated this mean measurement. We therefore randomly selected 258 men between the ages of 18 and 23 years from a population of 2,000 young French men seen at the National Service Selection Centre in order to measure the scrotal temperature over each testis and in the median raphe in order to determine the mean and median values for these temperatures. For a mean room temperature of 23 +/- 0.5 degrees C with a range of 18 to 31 degrees C, the mean right and left scrotal temperature was 34.2 +/- 0.1 degree C and the mean medioscrotal temperature was 34.4 +/- 0.1 degree C. Scrotal temperature was very significantly correlated to room temperature and its variations. It was therefore impossible to define a normal value for scrotal temperature. Only measurement of scrotal temperature at neutral room temperature, between 21 and 25 degrees C, is able to provide a reference value for scrotal temperature. In this study, the mean scrotal temperature under these conditions was 34.4 +/- 0.2 degree C, i.e. 2.5 degrees C less than body temperature. In the 12.9% of cases with left varicocele, left scrotal temperature was significantly higher than in the absence of varicocele and was also higher than right Scrotal temperature. The authors also determined the dimensions of the testes.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Evaluation of the effect of aromatherapy with Rosa damascena Mill. on postoperative pain intensity in hospitalized children in selected hospitals affiliated to Isfahan University of Medical Sciences in 2013: A randomized clinical trial

    Science.gov (United States)

    Marofi, Maryam; Sirousfard, Motahareh; Moeini, Mahin; Ghanadi, Alireza

    2015-01-01

    Background: Pain is the common complication after a surgery. The aim of this study was to evaluate the effect of aromatherapy with Rosa damascena Mill. on the postoperative pain in children. Materials and Methods: In a double-blind, placebo-controlled clinical trial, we selected 64 children of 3–6 years of age through convenient sampling and divided them randomly into two groups. Patients in group A were given inhalation aromatherapy with R. damascena Mill., and in group B, the patients were given almond oil as a placebo. Inhalation aromatherapy was used at the first time of subjects’ arrival to the ward and then at 3, 6, 9, and 12 h afterward. Common palliative treatments to relieve pain were used in both groups. Thirty minutes after aromatherapy, the postoperative pain in children was evaluated with the Toddler Preschooler Postoperative Pain Scale (TPPPS). Data were statistically analyzed using Chi-square test, one-way analysis of variance (ANOVA), and repeated measures ANOVA. Results: There was no significant difference in pain scores at the first time of subjects’ arrival to the ward (before receiving any aromatherapy or palliative care) between the two groups. After each time of aromatherapy and at the end of treatment, the pain score was significantly reduced in the aromatherapy group with R. damascena Mill. compared to the placebo group. Conclusions: According to our results, aromatherapy with R. damascena Mill. can be used in postoperative pain in children, together with other common treatments without any significant side effects. PMID:25878704

  14. Evaluating the effectiveness of selected community-level interventions on key maternal, child health, and prevention of mother-to-child transmission of HIV outcomes in three countries (the ACCLAIM Project): a study protocol for a randomized controlled trial.

    Science.gov (United States)

    Woelk, Godfrey B; Kieffer, Mary Pat; Walker, Damilola; Mpofu, Daphne; Machekano, Rhoderick

    2016-02-16

    original study design. We purposively selected facilities in the districts/regions though originally the study clusters were to be randomly selected. Lifelong antiretroviral therapy for all HIV positive pregnant and lactating women, Option B+, was implemented in the three countries during the study period, with the potential for a differential impact by study arm. Implementation however, was rapidly done across the districts/regions, so that there is unlikely be this potential confounding. We developed a system of monitoring and documentation of potential confounding activities or actions, and these data will be incorporated into analyses at the conclusion of the project. Strengthens of the study are that it tests multilevel interventions, utilizes program as well as study specific and individual data, and it is conducted under "real conditions" leading to more robust findings. Limitations of the protocol include the lack of a true control arm and inadequate control for the potential effect of Option B+, such as the intensification of messages as the importance of early ANC and male partner testing. ClinicalTrials.gov (study ID: NCT01971710) Protocol version 5, 30 July 2013, registered 13 August 2013.

  15. Using Random Numbers in Science Research Activities.

    Science.gov (United States)

    Schlenker, Richard M.; And Others

    1996-01-01

    Discusses the importance of science process skills and describes ways to select sets of random numbers for selection of subjects for a research study in an unbiased manner. Presents an activity appropriate for grades 5-12. (JRH)

  16. Risk of Parkinson's disease following zolpidem use: a retrospective, population-based cohort study.

    Science.gov (United States)

    Huang, Hui-Chun; Tsai, Chon-Haw; Muo, Chih-Hsin; Lin, Kang-Hsu; Lu, Ming-Kuei; Sung, Fung-Chang; Kao, Chia-Hung

    2015-01-01

    To evaluate the influence of long-term zolpidem use on the incidence of developing Parkinson's disease. 2,961 subjects who used zolpidem for the first time longer than 3 months between 1998 and 2000 were identified in the National Health Insurance system of Taiwan. Subjects without a history of zolpidem use were randomly selected as a comparison cohort and frequency matched to zolpidem users based on age, sex, and index date. The diagnosis of Parkinson's disease was based on the criteria of the International Classification of Diseases, Ninth Revision, Clinical Modification. Its incidence until the end of 2009 was calculated and its hazard ratios (HRs) and 95% CIs were estimated using Cox proportional hazards regression models and Kaplan-Meier analysis. The overall incidence of Parkinson's disease was greater among zolpidem users than in the comparison cohort (HR = 1.88; 95% CI, 1.45-2.45). However, there was no difference in Parkinson's disease incidence between these 2 cohorts after 5 years of observation. The risk of Parkinson's disease increased with increasing zolpidem dose, with an HR of 0.70 for low-dose users (zolpidem only (HR = 2.35; 95% CI, 1.66-3.33) compared to those using benzodiazepines only (HR = 1.31; 95% CI, 0.91-1.90). By stratified analysis, zolpidem use with concurrent depression (HR = 4.79) increased the risk of Parkinson's disease compared to that of zolpidem users without concurrent depression. Zolpidem use might unmask preclinical Parkinson's disease, especially in patients with depression. However, large population-based, unbiased, randomized trials are warranted to confirm this finding. © Copyright 2015 Physicians Postgraduate Press, Inc.

  17. New Delhi Birth Cohort

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. New Delhi Birth Cohort. In childhood Less than 1% were obese (IOTF 30 kg/m2). Mean BMI SD ranged from –0.4 to –1.0 (CDC). At 26-32 years 10% were obese (BMI >30 kg/m2). ~50% overweight (BMI > 25 kg/m2);. ~65% overweight (BMI > 23 kg/m2). 10% had IGT.

  18. Efficacy and tolerability balance of oxycodone/naloxone and tapentadol in chronic low back pain with a neuropathic component: a blinded end point analysis of randomly selected routine data from 12-week prospective open-label observations.

    Science.gov (United States)

    Ueberall, Michael A; Mueller-Schwefe, Gerhard H H

    2016-01-01

    To evaluate the benefit-risk profile (BRP) of oxycodone/naloxone (OXN) and tapentadol (TAP) in patients with chronic low back pain (cLBP) with a neuropathic component (NC) in routine clinical practice. This was a blinded end point analysis of randomly selected 12-week routine/open-label data of the German Pain Registry on adult patients with cLBP-NC who initiated an index treatment in compliance with the current German prescribing information between 1st January and 31st October 2015 (OXN/TAP, n=128/133). Primary end point was defined as a composite of three efficacy components (≥30% improvement of pain, pain-related disability, and quality of life each at the end of observation vs baseline) and three tolerability components (normal bowel function, absence of either central nervous system side effects, and treatment-emergent adverse event [TEAE]-related treatment discontinuation during the observation period) adopted to reflect BRP assessments under real-life conditions. Demographic as well as baseline and pretreatment characteristics were comparable for the randomly selected data sets of both index groups without any indicators for critical selection biases. Treatment with OXN resulted formally in a BRP noninferior to that of TAP and showed a significantly higher primary end point response vs TAP (39.8% vs 25.6%, odds ratio: 1.93; P =0.014), due to superior analgesic effects. Between-group differences increased with stricter response definitions for all three efficacy components in favor of OXN: ≥30%/≥50%/≥70% response rates for OXN vs TAP were seen for pain intensity in 85.2%/67.2%/39.1% vs 83.5%/54.1%/15.8% ( P = ns/0.031/<0.001), for pain-related disability in 78.1%/64.8%/43.8% vs 66.9%/50.4%/24.8% ( P =0.043/0.018/0.001), and for quality of life in 76.6%/68.0%/50.0% vs 63.9%/54.1%/34.6% ( P =0.026/0.022/0.017). Overall, OXN vs TAP treatments were well tolerated, and proportions of patients who either maintained a normal bowel function (68.0% vs 72

  19. Cohort profile: Pacific Islands Families (PIF) growth study, Auckland, New Zealand

    Science.gov (United States)

    Rush, E; Oliver, M; Plank, L D; Taylor, S; Iusitini, L; Jalili-Moghaddam, S; Savila, F; Paterson, J; Tautolo, E

    2016-01-01

    Purpose This article profiles a birth cohort of Pacific children participating in an observational prospective study and describes the study protocol used at ages 14–15 years to investigate how food and activity patterns, metabolic risk and family and built environment are related to rates of physical growth of Pacific children. Participants From 2000 to 2015, the Pacific Islands Families Study has followed, from birth, the growth and development of over 1000 Pacific children born in Auckland, New Zealand. In 2014, 931 (66%) of the original cohort had field measures of body composition, blood pressure and glycated haemoglobin. A nested subsample (n=204) was drawn by randomly selecting 10 males and 10 females from each decile of body weight. These participants had measurement of body composition by dual-energy X-ray absorptiometry, food frequency, 6 min walk test and accelerometer-determined physical activity and sedentary behaviours, and blood biomarkers for metabolic disease such as diabetes. Built environment variables were generated from individual addresses. Findings to date Compared to the Centres for Disease Control and Prevention (CDC) reference population with mean SD scores (SDS) of 0, this cohort of 931 14-year-olds was taller, weighed more and had a higher body mass index (BMI) (mean SDS height >0.6, weight >1.6 and BMI >1.4). 7 of 10 youth were overweight or obese. The nested-sampling frame achieved an even distribution by body weight. Future plans Cross-sectional relationships between body size, fatness and growth rate, food patterns, activity patterns, pubertal development, risks for diabetes and hypertension and the family and wider environment will be examined. In addition, analyses will investigate relationships with data collected earlier in the life course and measures of the cohort in the future. Understanding past and present influences on child growth and health will inform timely interventions to optimise future health and reduce

  20. Random magnetism

    International Nuclear Information System (INIS)

    Tsallis, C.

    1980-03-01

    The 'ingredients' which control a phase transition in well defined system as well as in random ones (e.g. random magnetic systems) are listed and discussed within a somehow unifying perspective. Among these 'ingredients' we find the couplings and elements responsible for the cooperative phenomenon, the topological connectivity as well as possible topological incompatibilities, the influence of new degrees of freedom, the order parameter dimensionality, the ground state degeneracy and finally the 'quanticity' of the system. The general trends, though illustrated in magnetic systems, essentially hold for all phase transitions, and give a basis for connection of this area with Field theory, Theory of dynamical systems, etc. (Author) [pt

  1. Random magnetism

    International Nuclear Information System (INIS)

    Tsallis, C.

    1981-01-01

    The 'ingredients' which control a phase transition in well defined systems as well as in random ones (e.q. random magnetic systems) are listed and discussed within a somehow unifying perspective. Among these 'ingredients' the couplings and elements responsible for the cooperative phenomenon, the topological connectivity as well as possible topological incompatibilities, the influence of new degrees of freedom, the order parameter dimensionality, the ground state degeneracy and finally the 'quanticity' of the system are found. The general trends, though illustrated in magnetic systems, essentially hold for all phase transitions, and give a basis for connection of this area with Field theory, Theory of dynamical systems, etc. (Author) [pt

  2. Implementing multifactorial psychotherapy research in online virtual environments (IMPROVE-2): study protocol for a phase III trial of the MOST randomized component selection method for internet cognitive-behavioural therapy for depression.

    Science.gov (United States)

    Watkins, Edward; Newbold, Alexandra; Tester-Jones, Michelle; Javaid, Mahmood; Cadman, Jennifer; Collins, Linda M; Graham, John; Mostazir, Mohammod

    2016-10-06

    Depression is a global health challenge. Although there are effective psychological and pharmaceutical interventions, our best treatments achieve remission rates less than 1/3 and limited sustained recovery. Underpinning this efficacy gap is limited understanding of how complex psychological interventions for depression work. Recent reviews have argued that the active ingredients of therapy need to be identified so that therapy can be made briefer, more potent, and to improve scalability. This in turn requires the use of rigorous study designs that test the presence or absence of individual therapeutic elements, rather than standard comparative randomised controlled trials. One such approach is the Multiphase Optimization Strategy, which uses efficient experimentation such as factorial designs to identify active factors in complex interventions. This approach has been successfully applied to behavioural health but not yet to mental health interventions. A Phase III randomised, single-blind balanced fractional factorial trial, based in England and conducted on the internet, randomized at the level of the patient, will investigate the active ingredients of internet cognitive-behavioural therapy (CBT) for depression. Adults with depression (operationalized as PHQ-9 score ≥ 10), recruited directly from the internet and from an UK National Health Service Improving Access to Psychological Therapies service, will be randomized across seven experimental factors, each reflecting the presence versus absence of specific treatment components (activity scheduling, functional analysis, thought challenging, relaxation, concreteness training, absorption, self-compassion training) using a 32-condition balanced fractional factorial design (2 IV 7-2 ). The primary outcome is symptoms of depression (PHQ-9) at 12 weeks. Secondary outcomes include symptoms of anxiety and process measures related to hypothesized mechanisms. Better understanding of the active ingredients of

  3. Implementing multifactorial psychotherapy research in online virtual environments (IMPROVE-2: study protocol for a phase III trial of the MOST randomized component selection method for internet cognitive-behavioural therapy for depression

    Directory of Open Access Journals (Sweden)

    Edward Watkins

    2016-10-01

    Full Text Available Abstract Background Depression is a global health challenge. Although there are effective psychological and pharmaceutical interventions, our best treatments achieve remission rates less than 1/3 and limited sustained recovery. Underpinning this efficacy gap is limited understanding of how complex psychological interventions for depression work. Recent reviews have argued that the active ingredients of therapy need to be identified so that therapy can be made briefer, more potent, and to improve scalability. This in turn requires the use of rigorous study designs that test the presence or absence of individual therapeutic elements, rather than standard comparative randomised controlled trials. One such approach is the Multiphase Optimization Strategy, which uses efficient experimentation such as factorial designs to identify active factors in complex interventions. This approach has been successfully applied to behavioural health but not yet to mental health interventions. Methods/Design A Phase III randomised, single-blind balanced fractional factorial trial, based in England and conducted on the internet, randomized at the level of the patient, will investigate the active ingredients of internet cognitive-behavioural therapy (CBT for depression. Adults with depression (operationalized as PHQ-9 score ≥ 10, recruited directly from the internet and from an UK National Health Service Improving Access to Psychological Therapies service, will be randomized across seven experimental factors, each reflecting the presence versus absence of specific treatment components (activity scheduling, functional analysis, thought challenging, relaxation, concreteness training, absorption, self-compassion training using a 32-condition balanced fractional factorial design (2IV 7-2. The primary outcome is symptoms of depression (PHQ-9 at 12 weeks. Secondary outcomes include symptoms of anxiety and process measures related to hypothesized mechanisms

  4. A protocol for a three-arm cluster randomized controlled superiority trial investigating the effects of two pedagogical methodologies in Swedish preschool settings on language and communication, executive functions, auditive selective attention, socioemotional skills and early maths skills.

    Science.gov (United States)

    Gerholm, Tove; Hörberg, Thomas; Tonér, Signe; Kallioinen, Petter; Frankenberg, Sofia; Kjällander, Susanne; Palmer, Anna; Taguchi, Hillevi Lenz

    2018-06-19

    During the preschool years, children develop abilities and skills in areas crucial for later success in life. These abilities include language, executive functions, attention, and socioemotional skills. The pedagogical methods used in preschools hold the potential to enhance these abilities, but our knowledge of which pedagogical practices aid which abilities, and for which children, is limited. The aim of this paper is to describe an intervention study designed to evaluate and compare two pedagogical methodologies in terms of their effect on the above-mentioned skills in Swedish preschool children. The study is a randomized control trial (RCT) where two pedagogical methodologies were tested to evaluate how they enhanced children's language, executive functions and attention, socioemotional skills, and early maths skills during an intensive 6-week intervention. Eighteen preschools including 28 units and 432 children were enrolled in a municipality close to Stockholm, Sweden. The children were between 4;0 and 6;0 years old and each preschool unit was randomly assigned to either of the interventions or to the control group. Background information on all children was collected via questionnaires completed by parents and preschools. Pre- and post-intervention testing consisted of a test battery including tests on language, executive functions, selective auditive attention, socioemotional skills and early maths skills. The interventions consisted of 6 weeks of intensive practice of either a socioemotional and material learning paradigm (SEMLA), for which group-based activities and interactional structures were the main focus, or an individual, digitally implemented attention and math training paradigm, which also included a set of self-regulation practices (DIL). All preschools were evaluated with the ECERS-3. If this intervention study shows evidence of a difference between group-based learning paradigms and individual training of specific skills in terms of

  5. Parental separation and pediatric cancer: a Danish cohort study.

    Science.gov (United States)

    Grant, Sally; Carlsen, Kathrine; Bidstrup, Pernille Envold; Bastian, Gro Samsø; Lund, Lasse Wegener; Dalton, Susanne Oksbjerg; Johansen, Christoffer

    2012-05-01

    The purpose of this study was to determine the risk for separation (ending cohabitation) of the parents of a child with a diagnosis of cancer. In a nationwide cohort, we compared the risk for ending cohabitation of the parents of 2450 children (aged 0-20 years) given a diagnosis of cancer with the risk of parents of 44 853 randomly selected, gender- and age-matched cancer-free children. We adjusted for socioeconomic position and demographic factors. Rate ratios and 95% confidence intervals for separation were estimated in a Cox proportional hazards model. The parents of children with cancer did not have a higher risk for separation than the general population (rate ratio: 1.00 [95% confidence interval: 0.91-1.10]). Separate analyses according to type of cancer and survival of the child similarly yielded null results. Experiencing cancer in a child does not seem to be a risk factor for separation. Our study will allow clinicians to reassure parents and to support them in facing the trauma of cancer in their child.

  6. Random Decrement

    DEFF Research Database (Denmark)

    Asmussen, J.C.; Ibrahim, S.R.; Brincker, Rune

    Abstraet Thispaper demansirates how to use the Random Decrement (RD) technique for identification o flinear structures subjected to ambient excitation. The theory behind the technique will be presented and guidelines how to choose the different variables will be given. This is done by introducing...

  7. Random Decrement

    DEFF Research Database (Denmark)

    Asmussen, J. C.; Ibrahim, S. R.; Brincker, Rune

    This paper demonstrates how to use the Random Decrement (RD) technique for identification of linear structures subjected to ambient excitation. The theory behind the technique will be presented and guidelines how to choose the different variables will be given. This is done by introducing a new...

  8. Random Decrement

    DEFF Research Database (Denmark)

    Asmussen, J. C.; Ibrahim, R.; Brincker, Rune

    1998-01-01

    This paper demonstrates how to use the Random Decrement (RD) technique for identification of linear structures subjected to ambient excitation. The theory behind the technique will be presented and guidelines how to choose the different variables will be given. This is done by introducing a new...

  9. Random dynamics

    International Nuclear Information System (INIS)

    Bennett, D.L.; Brene, N.; Nielsen, H.B.

    1986-06-01

    The goal of random dynamics is the derivation of the laws of Nature as we know them (standard model) from inessential assumptions. The inessential assumptions made here are expressed as sets of general models at extremely high energies: gauge glass and spacetime foam. Both sets of models lead tentatively to the standard model. (orig.)

  10. Random dynamics

    International Nuclear Information System (INIS)

    Bennett, D.L.

    1987-01-01

    The goal of random dynamics is the derivation of the laws of Nature as we know them (standard model) from inessential assumptions. The inessential assumptions made here are expressed as sets of general models at extremely high energies: Gauge glass and spacetime foam. Both sets of models lead tentatively to the standard model. (orig.)

  11. Random Dynamics

    Science.gov (United States)

    Bennett, D. L.; Brene, N.; Nielsen, H. B.

    1987-01-01

    The goal of random dynamics is the derivation of the laws of Nature as we know them (standard model) from inessential assumptions. The inessential assumptions made here are expressed as sets of general models at extremely high energies: gauge glass and spacetime foam. Both sets of models lead tentatively to the standard model.

  12. Cancer and the risk for taking early retirement pension: a Danish cohort study

    DEFF Research Database (Denmark)

    Carlsen, Kathrine; Oksbjerg Dalton, Susanne; Frederiksen, Kirsten

    2008-01-01

    , physical and psychological comorbidity, low education and low income. Three risk categories were identified (high, medium and low) by cancer site and we found that in the high risk category, people diagnosed with leukemia, prostate cancer or ovary cancer had a more than two-fold increased risk for ERP......AIMS: The purpose of this study was to determine the risk for taking early retirement pension (ERP) in cancer survivors who were working at the time of diagnosis. METHODS: We conducted a nationwide and population based cohort study including 44,905 persons aged 30-60 years diagnosed with selected...... cancers in the period 1981-2000 and 211,562 randomly sampled cancer-free controls. Information on socioeconomic status, demography and physical and psychiatric comorbidity was obtained from Danish administrative registries. RESULTS: We analyzed the risk for ERP adjusted for known risk factors and found...

  13. Increased dementia risk predominantly in diabetes mellitus rather than in hypertension or hyperlipidemia: a population-based cohort study.

    Science.gov (United States)

    Fan, Yen-Chun; Hsu, Jung-Lung; Tung, Hong-Yi; Chou, Chia-Chi; Bai, Chyi-Huey

    2017-02-06

    The pathophysiology of insulin resistance-induced hypertension and hyperlipidemia might entail differences in dementia risk in cases with hypertension and hyperlipidemia without prior diabetes mellitus (DM). This study investigated whether incident hypertension, incident hyperlipidemia, or both, increased the dementia risk in patients with and without DM. A nationwide retrospective cohort study was conducted. The study sample was obtained from the National Health Insurance Research Database. We enrolled 10,316 patients with a new diagnosis of DM between 2000 and 2002 in the DM cohort. For the same period, we randomly selected 41,264 patients without DM in the non-DM cohort (matched by age and sex at a 1:4 ratio with the DM cohort). Both cohorts were then separately divided into four groups on the basis of incident hypertension or incident hyperlipidemia status. In total, 51,580 patients aged between 20 and 99 years were enrolled. The dementia risk was higher in the DM cohort than in the non-DM cohort (adjusted hazard ratio (HR) = 1.47, 95% confidence interval (CI) = 1.30-1.67, p hypertension and hyperlipidemia did not significantly increase compared with that in those without hypertension and hyperlipidemia (p = 0.529). Similar results were observed in those with either hypertension (p = 0.341) or hyperlipidemia (p = 0.189). In the non-DM cohort, patients with both hypertension and hyperlipidemia had a higher dementia risk (adjusted HR = 1.33, 95% CI = 1.09-1.63, p = 0.006). The results remained largely unchanged in patients with only hypertension (adjusted HR = 1.22, 95% CI = 1.05-1.40, p = 0.008). However, the dementia risk did not increase significantly in patients with only hyperlipidemia (p = 0.187). The development of hypertension, hyperlipidemia, or both, following a diagnosis of incident diabetes is secondary to diabetes onset and likely mediated through insulin resistance associated with diabetes, which

  14. Direct random insertion mutagenesis of Helicobacter pylori.

    NARCIS (Netherlands)

    Jonge, de R.; Bakker, D.; Vliet, van AH; Kuipers, E.J.; Vandenbroucke-Grauls, C.M.J.E.; Kusters, J.G.

    2003-01-01

    Random insertion mutagenesis is a widely used technique for the identification of bacterial virulence genes. Most strategies for random mutagenesis involve cloning in Escherichia coli for passage of plasmids or for phenotypic selection. This can result in biased selection due to restriction or

  15. Direct random insertion mutagenesis of Helicobacter pylori

    NARCIS (Netherlands)

    de Jonge, Ramon; Bakker, Dennis; van Vliet, Arnoud H. M.; Kuipers, Ernst J.; Vandenbroucke-Grauls, Christina M. J. E.; Kusters, Johannes G.

    2003-01-01

    Random insertion mutagenesis is a widely used technique for the identification of bacterial virulence genes. Most strategies for random mutagenesis involve cloning in Escherichia coli for passage of plasmids or for phenotypic selection. This can result in biased selection due to restriction or

  16. Statins and Hip Fracture Prevention – A Population Based Cohort Study in Women

    Science.gov (United States)

    Helin-Salmivaara, Arja; Korhonen, Maarit J.; Lehenkari, Petri; Junnila, Seppo Y. T.; Neuvonen, Pertti J.; Ruokoniemi, Päivi; Huupponen, Risto

    2012-01-01

    Objective To study the association of long-term statin use and the risk of low-energy hip fractures in middle-aged and elderly women. Design A register-based cohort study. Setting Finland. Participants Women aged 45–75 years initiating statin therapy between 1996 and 2001 with adherence to statins ≥80% during the subsequent five years (n = 40 254), a respective cohort initiating hypertension drugs (n = 41 610), and women randomly selected from the population (n = 62 585). Main Outcome Measures Incidence rate of and hazard ratio (HR) for low-energy hip fracture during the follow-up extending up to 7 years after the 5-year exposure period. Results Altogether 199 low-energy hip fractures occurred during the 135 330 person-years (py) of follow-up in the statin cohort, giving an incidence rate of 1.5 hip fractures per 1000 py. In the hypertension and the population cohorts, the rates were 2.0 per 1000 py (312 fractures per 157 090 py) and 1.0 per 1000 py (212 fractures per 216 329 py), respectively. Adjusting for a propensity score and individual variables strongly predicting the outcome, good adherence to statins for five years was associated with a 29% decreased risk (HR 0.71; 95% CI 0.58–0.86) of a low-energy hip fracture in comparison with adherent use of hypertension drugs. The association was of the same magnitude when comparing the statin users with the population cohort, the HR being 0.69 (0.55–0.87). When women with poor (statins were compared to those with good adherence to hypertension drugs (≥80%) or to the population cohort, the protective effect associated with statin use attenuated with the decreasing level of adherence. Conclusions 5-year exposure to statins is associated with a reduced risk of low-energy hip fracture in women aged 50–80 years without prior hospitalizations for fractures. PMID:23144731

  17. Association between adult otitis media and nasopharyngeal cancer: A nationwide population-based cohort study

    International Nuclear Information System (INIS)

    Huang, Wen-Yen; Lin, Che-Chen; Jen, Yee-Min; Lin, Kuen-Tze; Yang, Muh-Hwa; Chen, Chang-Ming; Chang, Ying-Nan; Sung, Fung-Chang; Kao, Chia-Hung

    2012-01-01

    Purpose: To determine whether the diagnosis of otitis media (OM) in adults is associated with an increased risk for the subsequent development of nasopharyngeal cancer (NPC) using a nationwide population-based retrospective study. Methods and materials: We selected 13,513 adult patients that had been previously diagnosed with OM between 2000 and 2005 from the Taiwan Longitudinal Health Insurance Database 2000 as the study cohort, and randomly extracted the data of 135,130 participants matched by sex, age, and baseline year for the comparison cohort. The follow-up period was terminated upon developing NPC, withdrawal from the national health insurance system, or the end of 2009. Cumulative incidences and hazard ratios (HRs) of NPC development were determined. Results: The subsequent NPC incidence rates in the OM and comparison cohorts were 6.41 and 0.58 per 10 000 person-years, respectively (adjusted HR, 11.04; 95% CI, 7.68–5.87; P < 0.0001). The NPC risk for males was significantly higher than that for females (adjusted HR = 3.24; 95% CI, 2.16–4.85). In both female and male patients, the diagnosis of OM was associated with a significantly increased risk for NPC (adjusted HR, 11.91 vs. 10.78, respectively). Among the OM cohort, 62 participants were subsequently diagnosed with NPC, with 71% of them occurring within 1 year following the diagnosis of OM. However, even after 5-year follow-up, the OM cohort still displayed a higher risk for NPC (adjusted HR = 2.50). Stratified by the frequency of OM episodes, more than one episode per year had a significantly greater risk of developing NPC, compared with the comparison cohort (HR = 29.22; 95% CI, 20.19–42.27). Conclusion: We found that adult OM is a warning sign for the development of NPC in Taiwan, with approximately an 11-fold higher risk for adult OM patients. We recommend that OM patients undergo follow-up examinations for at least 5 years. To extrapolate our findings, further studies are warranted in other

  18. The Odense Child Cohort

    DEFF Research Database (Denmark)

    Kyhl, Henriette Boye; Jensen, Tina Kold; Barington, Torben

    2015-01-01

    , the Odense Childhood Cohort (OCC) study aims to provide new information about the environmental impact on child health by sequential follow-up to 18 years of age among children born between 2010 and 2012. METHODS: A total of 2874 of 6707 pregnancies (43%) were recruited between January 2010 and December 2012...... provides material for in-depth analysis of environmental and genetic factors that are important for child health and disease. Registry data from non-participating women and infants are available which ensures a high degree of comparable data....

  19. Lack of efficacy of resveratrol on C-reactive protein and selected cardiovascular risk factors--Results from a systematic review and meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Sahebkar, Amirhossein; Serban, Corina; Ursoniu, Sorin; Wong, Nathan D; Muntner, Paul; Graham, Ian M; Mikhailidis, Dimitri P; Rizzo, Manfredi; Rysz, Jacek; Sperling, Laurence S; Lip, Gregory Y H; Banach, Maciej

    2015-01-01

    Numerous studies have suggested that oral supplementation with resveratrol exerts cardioprotective effects, but evidence of the effects on C-reactive protein (CRP) plasma levels and other cardiovascular (CV) risk factors is inconclusive. Therefore, we performed a meta-analysis to evaluate the efficacy of resveratrol supplementation on plasma CRP concentrations and selected predictors of CV risk. The search included PUBMED, Cochrane Library, Web of Science, Scopus, and EMBASE (up to August 31, 2014) to identify RCTs investigating the effects of resveratrol supplementation on selected CV risk factors. Quantitative data synthesis was performed using a random-effects model, with weighted mean difference (WMD) and 95% confidence intervals (CI) as summary statistics. Meta-analysis of data from 10 RCTs (11 treatment arms) did not support a significant effect of resveratrol supplementation in altering plasma CRP concentrations (WMD: -0.144 mg/L, 95% CI: -0.968-0.680, p = 0.731). Resveratrol supplementation was not found to alter plasma levels of total cholesterol (WMD: 1.49 mg/dL, 95% CI: -14.96-17.93, p = 0.859), low density lipoprotein cholesterol (WMD: -0.31 mg/dL, 95% CI: -9.57-8.95, p = 0.948), triglycerides (WMD: 2.67 mg/dL, 95% CI: -28.34-33.67, p = 0.866), and glucose (WMD: 1.28 mg/dL, 95% CI: -5.28-7.84, p = 0.703). It also slightly reduced high density lipoprotein cholesterol concentrations (WMD: -4.18 mg/dL, 95% CI: -6.54 to -1.82, p = 0.001). Likewise, no significant effect was observed on systolic (WMD: 0.82 mmHg, 95% CI: -8.86-10.50, p = 0.868) and diastolic blood pressure (WMD: 1.72 mm Hg, 95% CI: -6.29-9.73, p=0.674). This meta-analysis of available RCTs does not suggest any benefit of resveratrol supplementation on CV risk factors. Larger, well-designed trials are necessary to confirm these results. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  20. Polymorphisms in NFKB1 and TLR4 and Interaction with Dietary and Life Style Factors in Relation to Colorectal Cancer in a Danish Prospective Case-Cohort Study

    DEFF Research Database (Denmark)

    Kopp, Tine Iskov; Andersen, Vibeke; Tjoøneland, Anne

    2015-01-01

    Maintenance of a balance between commensal bacteria and the mucosal immune system is crucial and intestinal dysbiosis may be a key event in the pathogenesis of colorectal cancer (CRC). The toll-like receptor 4 (TLR4) is an important pattern-recognition receptor that regulates inflammation...... and barrier function in the gut by a mechanism that involves activation of the nuclear factor-kappa B (NF-kappa B) transcription factor. Dietary and life style factors may impact these functions. We therefore used a Danish prospective case-cohort study of 1010 CRC cases and 1829 randomly selected participants...... from the Danish Diet, Cancer and Health cohort to investigate three polymorphisms in NFKB1 and TLR4 and their possible interactions with diet and life style factors in relation to risk of CRC. Homozygous carriage of the variant allele of the TLR4/rs5030728 polymorphism was associated with increased...

  1. Use of selective serotonin reuptake inhibitors and risk of re-operation due to post-surgical bleeding in breast cancer patients: a Danish population-based cohort study

    Directory of Open Access Journals (Sweden)

    Lash Timothy L

    2010-01-01

    Full Text Available Abstract Background Selective serotonin reuptake inhibitors (SSRI decrease platelet-function, which suggests that SSRI use may increase the risk of post-surgical bleeding. Few studies have investigated this potential association. Methods We conducted a population-based study of the risk of re-operation due to post-surgical bleeding within two weeks of primary surgery among Danish women with primary breast cancer. Patients were categorised according to their use of SSRI: never users, current users (SSRI prescription within 30 days of initial breast cancer surgery, and former users (SSRI prescription more than 30 days before initial breast cancer surgery. We calculated the risk of re-operation due to post-surgical bleeding within 14 days of initial surgery, and the relative risk (RR of re-operation comparing SSRI users with never users of SSRI adjusting for potential confounders. Results 389 of 14,464 women (2.7% were re-operated. 1592 (11% had a history of SSRI use. Risk of re-operation was 2.6% among never users, 7.0% among current SSRI users, and 2.7% among former users. Current users thus had an increased risk of re-operation due to post-operative bleeding (adjusted relative risk = 2.3; 95% confidence interval (CI = 1.4, 3.9 compared with never users. There was no increased risk of re-operation associated with former use of SSRI (RR = 0.93, 95% CI = 0.66, 1.3. Conclusions Current use of SSRI is associated with an increased risk of re-operation due to bleeding after surgery for breast cancer.

  2. Clinical variables serve as prognostic factors in a model for survival from glioblastoma multiforme: an observational study of a cohort of consecutive non-selected patients from a single institution

    International Nuclear Information System (INIS)

    Michaelsen, Signe Regner; Christensen, Ib Jarle; Grunnet, Kirsten; Stockhausen, Marie-Thérése; Broholm, Helle; Kosteljanetz, Michael; Poulsen, Hans Skovgaard

    2013-01-01

    Although implementation of temozolomide (TMZ) as a part of primary therapy for glioblastoma multiforme (GBM) has resulted in improved patient survival, the disease is still incurable. Previous studies have correlated various parameters to survival, although no single parameter has yet been identified. More studies and new approaches to identify the best and worst performing patients are therefore in great demand. This study examined 225 consecutive, non-selected GBM patients with performance status (PS) 0–2 receiving postoperative radiotherapy with concomitant and adjuvant TMZ as primary therapy. At relapse, patients with PS 0–2 were mostly treated by reoperation and/or combination with bevacizumab/irinotecan (BEV/IRI), while a few received TMZ therapy if the recurrence-free period was >6 months. Median overall survival and time to progression were 14.3 and 8.0 months, respectively. Second-line therapy indicated that reoperation and/or BEV/IRI increased patient survival compared with untreated patients and that BEV/IRI was more effective than reoperation alone. Patient age, ECOG PS, and use of corticosteroid therapy were significantly correlated with patient survival and disease progression on univariate analysis, whereas p53, epidermal growth factor receptor, and O 6 -methylguanine-DNA methyltransferase expression (all detected by immunohistochemistry), tumor size or multifocality, and extent of primary operation were not. A model based on age, ECOG PS, and corticosteroids use was able to predict survival probability for an individual patient. The survival of RT/TMZ-treated GBM patients can be predicted based on patient age, ECOG PS, and corticosteroid therapy status

  3. Frequency distribution of gastro esophageal reflux disease in inhalation injury: A historical cohort study.

    Science.gov (United States)

    Karbasi, Ashraf; Aliannejad, Rasoul; Ghanei, Mostafa; Sanamy, Mehran Noory; Alaeddini, Farshid; Harandi, Ali Amini

    2015-07-01

    There is no data on the prevalence and the association of gastro esophageal reflux disease (GERD) with toxic fume inhalation. Therefore, we aimed to evaluate the frequency distribution of GERD symptoms among the individuals with mild respiratory disorder due to the past history of toxic fume exposure to sulfur mustard (SM). In a historical cohort study, subjects were randomly selected from 7000 patients in a database of all those who had a history of previous exposure to a single high dose of SM gas during war. The control group was randomly selected from adjacent neighbors of the patients, and two healthy male subjects were chosen per patient. In this study, we used the validated Persian translation of Mayo Gastroesophageal Reflux Questionnaire to assess the frequency distribution of reflux disease. Relative frequency of GERD symptoms, was found to be significantly higher in the inhalation injury patients with an odds ratio of 8.30 (95% confidence interval [CI]: 4.73-14.55), and after adjustment for cigarette smoking, tea consumption, age, and body mass index, aspirin and chronic cough the odds ratio was found to be 4.41 (95% CI: 1.61-12.07). The most important finding of our study was the major GERD symptoms (heartburn and/or acid regurgitation once or more per week) among the individuals with the past history of exposure to SM toxic gas is substantially higher (4.4-fold) than normal populations.

  4. Random number generation and creativity.

    Science.gov (United States)

    Bains, William

    2008-01-01

    A previous paper suggested that humans can generate genuinely random numbers. I tested this hypothesis by repeating the experiment with a larger number of highly numerate subjects, asking them to call out a sequence of digits selected from 0 through 9. The resulting sequences were substantially non-random, with an excess of sequential pairs of numbers and a deficit of repeats of the same number, in line with previous literature. However, the previous literature suggests that humans generate random numbers with substantial conscious effort, and distractions which reduce that effort reduce the randomness of the numbers. I reduced my subjects' concentration by asking them to call out in another language, and with alcohol - neither affected the randomness of their responses. This suggests that the ability to generate random numbers is a 'basic' function of the human mind, even if those numbers are not mathematically 'random'. I hypothesise that there is a 'creativity' mechanism, while not truly random, provides novelty as part of the mind's defence against closed programming loops, and that testing for the effects seen here in people more or less familiar with numbers or with spontaneous creativity could identify more features of this process. It is possible that training to perform better at simple random generation tasks could help to increase creativity, through training people to reduce the conscious mind's suppression of the 'spontaneous', creative response to new questions.

  5. Risk of leukaemia in children infected with enterovirus: a nationwide, retrospective, population-based, Taiwanese-registry, cohort study.

    Science.gov (United States)

    Lin, Jiun-Nong; Lin, Cheng-Li; Lin, Ming-Chia; Lai, Chung-Hsu; Lin, Hsi-Hsun; Yang, Chih-Hui; Sung, Fung-Chang; Kao, Chia-Hung

    2015-10-01

    The association between enterovirus infections in children and risk of leukaemia is unclear. We aimed to assess the risk of leukaemia after enterovirus infection in children. We did a nationwide retrospective cohort study by analysing data from the National Health Insurance Research Database (NHIRD) in Taiwan. Children with enterovirus infections aged younger than 18 years were identified. With use of computer-generated random numbers, children not infected with enterovirus were randomly selected and frequency matched (1:1) with children infected with enterovirus by sex, age, urbanisation level, parental occupation, and index year of enterovirus infection. We only included children with complete baseline data for age and sex and who had at least three clinic visits with the diagnosis of enterovirus infection. The diagnosis date of the first clinic visit for the enterovirus infection was defined as the index date for initiation of follow-up person-year measurement and participants. All study patients were followed up until they developed leukaemia, were lost to follow-up, withdrew from the NHI programme, or until the end of the study without leukaemia (censored). Our primary endpoint was a diagnosis of leukaemia during follow-up. Insurance claims data for 3 054 336 children younger than 18 years were randomly selected from all insured children in the NHIRD. We identified 282 360 children infected with enterovirus and 282 355 children not infected with enterovirus between Jan 1, 2000, and Dec 31, 2007. The incidence density rates of leukaemia were 3·26 per 100 000 person-years for the enterovirus-infected and 5·84 per 100 000 person-years for the non-enterovirus-infected cohorts. The risk of leukaemia was significantly lower in the enterovirus-infected cohort than in the non-enterovirus-infected cohort (adjusted subhazard ratio [SHR] 0·44, 95% CI 0·31-0·60; penterovirus have a reduced risk of both lymphocytic leukaemia (adjusted SHR 0·44, 0·30-0

  6. Long-term Exposure to Particulate Matter Constituents and the Incidence of Coronary Events in 11 European Cohorts

    DEFF Research Database (Denmark)

    Wolf, Kathrin; Stafoggia, Massimo; Cesaroni, Giulia

    2015-01-01

    with incident coronary events. METHODS: Eleven cohorts from Finland, Sweden, Denmark, Germany, and Italy participated in this analysis. 5,157 incident coronary events were identified within 100,166 persons followed on average for 11.5 years. Long-term residential concentrations of PM PM 2.5 μm...... (PM2.5), and a priori selected constituents (copper, iron, nickel, potassium, silicon, sulfur, vanadium, and zinc) were estimated with land-use regression models. We used Cox proportional hazard models adjusted for a common set of confounders to estimate cohort-specific component effects...... with and without including PM mass, and random effects meta-analyses to pool cohort-specific results. RESULTS: A 100 ng/m³ increase in PM10 K and a 50 ng/m³ increase in PM2.5 K were associated with a 6% (hazard ratio and 95% confidence interval: 1.06 [1.01, 1.12]) and 18% (1.18 [1.06, 1.32]) increase in coronary...

  7. The IDEFICS Cohort

    DEFF Research Database (Denmark)

    Ahrens, Wolfgang; Bammann, Karin; Siani, Alfonso

    2011-01-01

    in eight countries in 2007–2008. Subjects and measurements: Baseline participants of the prospective cohort study were 16 224 children aged 2–9 years. Parents reported sociodemographic, behavioural, medical, nutritional and other lifestyle data for their children and families. Examinations of children...... included anthropometry, blood pressure, fitness, accelerometry, DNA from saliva and physiological markers in blood and urine. The built environment, sensory taste perception and other mechanisms of children's food choices and consumer behaviour were studied in subgroups. Results: Between 1507 and 2567......, children with a mean age of 6.0 years and an even sex distribution were recruited from each country. Of them, 82% lived in two-parent families. The distribution of standardised income levels differed by study sample, with low-income groups being strongly represented in Cyprus, Italy and Germany. At least...

  8. Analysis of Clinical Cohort Data Using Nested Case-control and Case-cohort Sampling Designs. A Powerful and Economical Tool.

    Science.gov (United States)

    Ohneberg, K; Wolkewitz, M; Beyersmann, J; Palomar-Martinez, M; Olaechea-Astigarraga, P; Alvarez-Lerma, F; Schumacher, M

    2015-01-01

    Sampling from a large cohort in order to derive a subsample that would be sufficient for statistical analysis is a frequently used method for handling large data sets in epidemiological studies with limited resources for exposure measurement. For clinical studies however, when interest is in the influence of a potential risk factor, cohort studies are often the first choice with all individuals entering the analysis. Our aim is to close the gap between epidemiological and clinical studies with respect to design and power considerations. Schoenfeld's formula for the number of events required for a Cox' proportional hazards model is fundamental. Our objective is to compare the power of analyzing the full cohort and the power of a nested case-control and a case-cohort design. We compare formulas for power for sampling designs and cohort studies. In our data example we simultaneously apply a nested case-control design with a varying number of controls matched to each case, a case cohort design with varying subcohort size, a random subsample and a full cohort analysis. For each design we calculate the standard error for estimated regression coefficients and the mean number of distinct persons, for whom covariate information is required. The formula for the power of a nested case-control design and the power of a case-cohort design is directly connected to the power of a cohort study using the well known Schoenfeld formula. The loss in precision of parameter estimates is relatively small compared to the saving in resources. Nested case-control and case-cohort studies, but not random subsamples yield an attractive alternative for analyzing clinical studies in the situation of a low event rate. Power calculations can be conducted straightforwardly to quantify the loss of power compared to the savings in the num-ber of patients using a sampling design instead of analyzing the full cohort.

  9. No Association between HMOX1 and Risk of Colorectal Cancer and No Interaction with Diet and Lifestyle Factors in a Prospective Danish Case-Cohort Study

    Directory of Open Access Journals (Sweden)

    Vibeke Andersen

    2015-01-01

    Full Text Available Red meat is a risk factor for colorectal cancer (CRC. We wanted to evaluate whether a functional polymorphism in the HMOX1 gene encoding heme oxygenase modifies risk of CRC or interacts with diet or lifestyle factors because this would identify heme or heme iron as a risk factor of CRC. The HMOX1 A-413T (rs2071746 was assessed in relation to risk of colorectal cancer (CRC and interactions with diet (red meat, fish, fiber, cereals, fruit and vegetables and lifestyle (use of non-steroidal anti-inflammatory drug and smoking status were assessed in a case-cohort study of 928 CRC cases and a comparison group of 1726 randomly selected participants from a prospective study of 57,053 persons. No association between HMOX1 A-413T and CRC risk was found (TT vs. AA + TA; IRR = 1.15, 95% CI: 0.98–1.36, p = 0.10 for the adjusted estimate. No interactions were found between diet or lifestyle and HMOX1 A-413T. HMOX1 A-413T was not associated with CRC risk and no interactions with diet or lifestyle were identified in this large, prospective cohort with high meat intake. The results reproduced the previous findings from the same cohort and did not support a link between heme or heme iron and colorectal cancer. These results should be sought and replicated in other well-characterized cohorts with high meat intake.

  10. Predictors of all-cause mortality among 514,866 participants from the Korean National Health Screening Cohort.

    Directory of Open Access Journals (Sweden)

    Choonghyun Ahn

    Full Text Available There is not enough evidence regarding how information obtained from general health check-ups can predict individual mortality based on long-term follow-ups and large sample sizes. This study evaluated the applicability of various health information and measurements, consisting of self-reported data, anthropometric measurements and laboratory test results, in predicting individual mortality.The National Health Screening Cohort included 514,866 participants (aged 40-79 years who were randomly selected from the overall database of the national health screening program in 2002-2003. Death was determined from causes of death statistics provided by Statistics Korea. We assessed variables that were collected at baseline and repeatedly measured for two consecutive years using traditional and time-variant Cox proportional hazards models in addition to random forest and boosting algorithms to identify predictors of 10-year all-cause mortality. Participants' age at enrollment, lifestyle factors, anthropometric measurements and laboratory test results were included in the prediction models. We used c-statistics to assess the discriminatory ability of the models, their external validity and the ratio of expected to observed numbers to evaluate model calibration. Eligibility of Medicaid and household income levels were used as inequality indexes.After the follow-up by 2013, 38,031 deaths were identified. The risk score based on the selected health information and measurements achieved a higher discriminatory ability for mortality prediction (c-statistics = 0.832, 0.841, 0.893, and 0.712 for Cox model, time-variant Cox model, random forest and boosting, respectively than that of the previous studies. The results were externally validated using the community-based cohort data (c-statistics = 0.814.Individuals' health information and measurements based on health screening can provide early indicators of their 10-year death risk, which can be useful for health

  11. Random tensors

    CERN Document Server

    Gurau, Razvan

    2017-01-01

    Written by the creator of the modern theory of random tensors, this book is the first self-contained introductory text to this rapidly developing theory. Starting from notions familiar to the average researcher or PhD student in mathematical or theoretical physics, the book presents in detail the theory and its applications to physics. The recent detections of the Higgs boson at the LHC and gravitational waves at LIGO mark new milestones in Physics confirming long standing predictions of Quantum Field Theory and General Relativity. These two experimental results only reinforce today the need to find an underlying common framework of the two: the elusive theory of Quantum Gravity. Over the past thirty years, several alternatives have been proposed as theories of Quantum Gravity, chief among them String Theory. While these theories are yet to be tested experimentally, key lessons have already been learned. Whatever the theory of Quantum Gravity may be, it must incorporate random geometry in one form or another....

  12. Sleep apnea and risk of vertigo: A nationwide population-based cohort study.

    Science.gov (United States)

    Tsai, Ming-Shao; Lee, Li-Ang; Tsai, Yao-Te; Yang, Yao-Hsu; Liu, Chia-Yen; Lin, Meng-Hung; Hsu, Cheng-Ming; Chen, Chin-Kuo; Li, Hsueh-Yu

    2018-03-01

    To investigate the risk of vertigo in patients with sleep apnea. Retrospective cohort study. This study used data from the National Health Insurance Research Database of Taiwan, a population-based database. A total of 5,025 patients who were newly diagnosed with sleep apnea between January 1, 1997, and December 31, 2012, were identified from the Longitudinal Health Insurance Database 2000, a nationally representative database of 1 million randomly selected patients. Moreover, 20,100 patients without sleep apnea were matched at a 1:4 ratio by age, sex, socioeconomic status, and urbanization level. Patients were followed up until death or the end of the study period (December 31, 2013). The primary outcome was the occurrence of vertigo. Patients with sleep apnea had a significantly higher cumulative incidence of vertigo than those without sleep apnea (P vertigo (hazard ratio, 1.71; 95% confidence interval [CI], 1.48-1.97; P diabetes mellitus, hypertension, stroke, and obesity. Sleep apnea was demonstrated to be an independent risk factor for vertigo. This is the first nationwide population-based cohort study to investigate the association between sleep apnea and vertigo. The findings strongly support that sleep apnea is an independent risk factor for vertigo. Based on the study results, physicians should be aware of potential vertigo occurrence following sleep apnea. 4. Laryngoscope, 128:763-768, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  13. SNRFCB: sub-network based random forest classifier for predicting chemotherapy benefit on survival for cancer treatment.

    Science.gov (United States)

    Shi, Mingguang; He, Jianmin

    2016-04-01

    Adjuvant chemotherapy (CTX) should be individualized to provide potential survival benefit and avoid potential harm to cancer patients. Our goal was to establish a computational approach for making personalized estimates of the survival benefit from adjuvant CTX. We developed Sub-Network based Random Forest classifier for predicting Chemotherapy Benefit (SNRFCB) based gene expression datasets of lung cancer. The SNRFCB approach was then validated in independent test cohorts for identifying chemotherapy responder cohorts and chemotherapy non-responder cohorts. SNRFCB involved the pre-selection of gene sub-network signatures based on the mutations and on protein-protein interaction data as well as the application of the random forest algorithm to gene expression datasets. Adjuvant CTX was significantly associated with the prolonged overall survival of lung cancer patients in the chemotherapy responder group (P = 0.008), but it was not beneficial to patients in the chemotherapy non-responder group (P = 0.657). Adjuvant CTX was significantly associated with the prolonged overall survival of lung cancer squamous cell carcinoma (SQCC) subtype patients in the chemotherapy responder cohorts (P = 0.024), but it was not beneficial to patients in the chemotherapy non-responder cohorts (P = 0.383). SNRFCB improved prediction performance as compared to the machine learning method, support vector machine (SVM). To test the general applicability of the predictive model, we further applied the SNRFCB approach to human breast cancer datasets and also observed superior performance. SNRFCB could provide recurrent probability for individual patients and identify which patients may benefit from adjuvant CTX in clinical trials.

  14. Benzodiazepines and risk of all cause mortality in adults: cohort study.

    Science.gov (United States)

    Patorno, Elisabetta; Glynn, Robert J; Levin, Raisa; Lee, Moa P; Huybrechts, Krista F

    2017-07-06

    Objectives  To evaluate the risk of all cause mortality associated with initiating compared with not initiating benzodiazepines in adults, and to address potential treatment barriers and confounding related to the use of a non-active comparator group. Design  Retrospective cohort study. Setting  Large de-identified US commercial healthcare database (Optum Clinformatics Datamart). Participants  1:1 high dimensional propensity score matched cohort of benzodiazepine initiators, and randomly selected benzodiazepine non-initiators with a medical visit within 14 days of the start of benzodiazepine treatment (n=1 252 988), between July 2004 and December 2013. To address treatment barriers and confounding, patients were required to have filled one or more prescriptions for any medication in the 90 days and 91-180 days before the index date (ie, the date of starting benzodiazepine treatment for initiators and the date of the selected medical visit for benzodiazepine non-initiators) and the high dimensional propensity score was estimated on the basis of more than 300 covariates. Main outcome measure  All cause mortality, determined by linkage with the Social Security Administration Death Master File. Results  Over a six month follow-up period, 5061 and 4691 deaths occurred among high dimensional propensity score matched benzodiazepine initiators versus non-initiators (9.3 v 9.4 events per 1000 person years; hazard ratio 1.00, 95% confidence interval 0.96 to 1.04). A 4% (95% confidence interval 1% to 8%) to 9% (2% to 7%) increase in mortality risk was observed associated with the start of benzodiazepine treatment for follow-ups of 12 and 48 months and in subgroups of younger patients and patients initiating short acting agents. In secondary analyses comparing 1:1 high dimensional propensity score matched patients initiating benzodiazepines with an active comparator, ie, patients starting treatment with selective serotonin reuptake inhibitor antidepressants

  15. Cohort: critical science

    Science.gov (United States)

    Digney, Bruce L.

    2007-04-01

    Unmanned vehicle systems is an attractive technology for the military, but whose promises have remained largely undelivered. There currently exist fielded remote controlled UGVs and high altitude UAV whose benefits are based on standoff in low complexity environments with sufficiently low control reaction time requirements to allow for teleoperation. While effective within there limited operational niche such systems do not meet with the vision of future military UxV scenarios. Such scenarios envision unmanned vehicles operating effectively in complex environments and situations with high levels of independence and effective coordination with other machines and humans pursing high level, changing and sometimes conflicting goals. While these aims are clearly ambitious they do provide necessary targets and inspiration with hopes of fielding near term useful semi-autonomous unmanned systems. Autonomy involves many fields of research including machine vision, artificial intelligence, control theory, machine learning and distributed systems all of which are intertwined and have goals of creating more versatile broadly applicable algorithms. Cohort is a major Applied Research Program (ARP) led by Defence R&D Canada (DRDC) Suffield and its aim is to develop coordinated teams of unmanned vehicles (UxVs) for urban environments. This paper will discuss the critical science being addressed by DRDC developing semi-autonomous systems.

  16. Gingival profiles in a select Asian cohort: A pilot study.

    Science.gov (United States)

    Lee, Wan Zhen; Ong, Marianne M A; Yeo, Alvin B-K

    2018-02-01

    The aim of the present study was to determine the facial gingival profiles of teeth with a healthy periodontium in an Asian population. A total of 51 patients with a healthy periodontium were examined. Gingival thickness (GT) and gingival width (GW) were assessed at the maxillary and mandibular incisors to the first molars. GT was measured by transgingival probing (GT-TGP), and probe visibility through the marginal gingiva (GT-TRAN) was assessed. Results between groups (anterior and posterior, tooth types) were analyzed using one-way analysis of variance and t-test. The mean age was 30.3±11.4 years, with 27 females and 24 males. The mean GT-TGP was 1.39±52 mm, while the mean GW was 4.59±1.34 mm. Considerable intra-individual and interindividual variation in GT (TGP and TRAN) was noted. GT increased from the anterior to posterior, and was thinnest at the mandibular centrals to the first premolars and maxillary canines. GT-TGP and GW were influenced by tooth type, plaque, recession, and TRAN, but not age, sex, or ethnicity. GW were recorded lowest at the mandibular canines and all premolars. Thin gingiva was recorded at 63.8%-92% (GT-TGPTGP and GT-TRAN. © 2017 John Wiley & Sons Australia, Ltd.

  17. Cholecystectomy can increase the risk of colorectal cancer: A meta-analysis of 10 cohort studies.

    Directory of Open Access Journals (Sweden)

    Yong Zhang

    Full Text Available This study aimed to elucidate the effects of cholecystectomy on the risk of colorectal cancer (CRC by conducting a meta-analysis of 10 cohort studies.The eligible cohort studies were selected by searching the PubMed and EMBASE databases from their origination to June 30, 2016, as well as by consulting the reference lists of the selected articles. Two authors individually collected the data from the 10 papers. When the data showed marked heterogeneity, we used a random-effects model to estimate the overall pooled risk; otherwise, a fixed effects model was employed.The final analysis included ten cohort studies. According to the Newcastle-Ottawa Scale (NOS, nine papers were considered high quality. After the data of these 9 studies were combined, an increased risk of CRC was found among the individuals who had undergone cholecystectomy (risk ratio (RR 1.22; 95% confidence interval (CI 1.08-1.38. In addition, we also found a promising increased risk for colon cancer (CC (RR 1.30, 95% CI 1.07-1.58, but no relationship between cholecystectomy and rectum cancer (RC (RR 1.09; 95% CI 0.89-1.34 was observed. Additionally, in the sub-group analysis of the tumor location in the colon, a positive risk for ascending colon cancer (ACC was found (RR 1.18, 95% CI 1.11-1.26. After combining the ACC, transverse colon cancer (TCC, sigmoid colon cancer (SCC and descending colon cancer (DCC patients, we found a positive relationship with cholecystectomy (RR 1.18, 95% CI 1.11-1.26. Furthermore, after combining the ACC and DCC patients, we also found a positive relationship with cholecystectomy (RR 1.28; 95% CI 1.11-1.26 in the sub-group analysis. In an additional sub-group analysis of patients from Western countries, there was a positive relationship between cholecystectomy and the risk of CRC (RR 1.20; 95% CI 1.05-1.36. Furthermore, a positive relationship between female gender and CRC was also found (RR 1.17; 95% CI 1.03-1.34. However, there was no relationship

  18. Incidence of Otitis Media in a Contemporary Danish National Birth Cohort

    DEFF Research Database (Denmark)

    Todbjerg, Tanja; Koch, Anders; Andersson, Mikael

    2014-01-01

    OBJECTIVES: In recent years welfare in Denmark has increased which might be expected to reduce otitis media (OM) incidence. We examined the age-specific incidence of OM in a nation-wide cohort of children aged 0-7 years born in 1996-2003 (Danish National Birth Cohort, DNBC). Only selection...

  19. Dietary pattern and 20 year mortality in elderly men in Finland, Italy and the Netherlands: Longitudinal cohort study.

    NARCIS (Netherlands)

    Huijbregts, P.; Feskens, E.J.M.; Résénen, L.; Fidanza, F.; Nissinen, A.; Menotti, A.; Kromhout, D.

    1997-01-01

    OBJECTIVE: To investigate the association of dietary pattern and mortality in international data. DESIGN: Cohort study with 20 years' follow up of mortality. SETTING: Five cohorts in Finland, the Netherlands, and Italy. SUBJECTS: Population based random sample of 3045 men aged 50-70 years in 1970.

  20. Pseudo-Random Number Generators

    Science.gov (United States)

    Howell, L. W.; Rheinfurth, M. H.

    1984-01-01

    Package features comprehensive selection of probabilistic distributions. Monte Carlo simulations resorted to whenever systems studied not amenable to deterministic analyses or when direct experimentation not feasible. Random numbers having certain specified distribution characteristic integral part of simulations. Package consists of collector of "pseudorandom" number generators for use in Monte Carlo simulations.

  1. Random pulse generator

    International Nuclear Information System (INIS)

    Guo Ya'nan; Jin Dapeng; Zhao Dixin; Liu Zhen'an; Qiao Qiao; Chinese Academy of Sciences, Beijing

    2007-01-01

    Due to the randomness of radioactive decay and nuclear reaction, the signals from detectors are random in time. But normal pulse generator generates periodical pulses. To measure the performances of nuclear electronic devices under random inputs, a random generator is necessary. Types of random pulse generator are reviewed, 2 digital random pulse generators are introduced. (authors)

  2. Random matrices and random difference equations

    International Nuclear Information System (INIS)

    Uppuluri, V.R.R.

    1975-01-01

    Mathematical models leading to products of random matrices and random difference equations are discussed. A one-compartment model with random behavior is introduced, and it is shown how the average concentration in the discrete time model converges to the exponential function. This is of relevance to understanding how radioactivity gets trapped in bone structure in blood--bone systems. The ideas are then generalized to two-compartment models and mammillary systems, where products of random matrices appear in a natural way. The appearance of products of random matrices in applications in demography and control theory is considered. Then random sequences motivated from the following problems are studied: constant pulsing and random decay models, random pulsing and constant decay models, and random pulsing and random decay models

  3. Assessment of fracture risk: value of random population-based samples--the Geelong Osteoporosis Study.

    Science.gov (United States)

    Henry, M J; Pasco, J A; Seeman, E; Nicholson, G C; Sanders, K M; Kotowicz, M A

    2001-01-01

    Fracture risk is determined by bone mineral density (BMD). The T-score, a measure of fracture risk, is the position of an individual's BMD in relation to a reference range. The aim of this study was to determine the magnitude of change in the T-score when different sampling techniques were used to produce the reference range. Reference ranges were derived from three samples, drawn from the same region: (1) an age-stratified population-based random sample, (2) unselected volunteers, and (3) a selected healthy subset of the population-based sample with no diseases or drugs known to affect bone. T-scores were calculated using the three reference ranges for a cohort of women who had sustained a fracture and as a group had a low mean BMD (ages 35-72 yr; n = 484). For most comparisons, the T-scores for the fracture cohort were more negative using the population reference range. The difference in T-scores reached 1.0 SD. The proportion of the fracture cohort classified as having osteoporosis at the spine was 26, 14, and 23% when the population, volunteer, and healthy reference ranges were applied, respectively. The use of inappropriate reference ranges results in substantial changes to T-scores and may lead to inappropriate management.

  4. Possibilities and considerations when merging dietary data from the world's two largest pregnancy cohorts: the Danish National Birth Cohort and the Norwegian Mother and Child Cohort Study.

    Science.gov (United States)

    Olsen, Sjurdur F; Birgisdottir, Bryndis Eva; Halldorsson, Thorhallur I; Brantsaeter, Anne Lise; Haugen, Margaretha; Torjusen, Hanne; Petersen, Sesilje B; Strøm, Marin; Meltzer, Helle Margrete

    2014-11-01

    To elucidate the research possibilities when merging data on maternal diet from the Danish National Birth Cohort (DNBC) and the Norwegian Mother and Child Cohort Study (MoBa), through comparison of (i) the methodology used for dietary assessment and (ii) the estimated intake of selected food groups in the two cohorts. Qualitative and quantitative comparison of the two dietary databases. Two national prospective pregnancy cohorts. Denmark, Norway. Comparison of food intake using food frequency questionnaires (FFQs). The FFQs had overlapping time windows and a majority of the questions in the two FFQs were comparable. Calculation principles shared similar features, including the software used and use of global questions to calibrate intakes of different food groups. A total of 63 food groups were defined that could be compared across the two cohorts; these were further aggregated down to 31 broader groups. A comparison of food intakes (grams/d) showed 39, 74 and 141% lower daily intakes of fish, potatoes and rice, respectively, in DNBC vs. MoBa and 39, 54 and 65% higher daily intakes of milk, butter and potatoes in DNBC vs. MoBa. For most other food groups, differences in consumption data were below 20%. The two FFQs are to a large extent compatible and substantial differences in dietary habits were observed between the two cohorts. This may strengthen studies using pooled analysis to examine diet-disease relations. This is a conclusion of great importance given the colossal and costly task involved to establish each of these two cohorts. © 2014 Nordic Federation of Societies of Obstetrics and Gynecology.

  5. Rationale and Design of a Randomized Clinical Comparison of Everolimus-Eluting (Xience V/Promus) and Sirolimus-Eluting (Cypher Select+) Coronary Stents in Unselected Patients with Coronary Heart Disease

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Thayssen, Per; Tilsted, Hans Henrik

    2010-01-01

    with Clinical Outcome (SORT OUT) IV trial was designed as a prospective, multi-center, open-label, all-comer, two-arm, randomized, non-inferiority study comparing the everolimus-eluting stent with the sirolimus-eluting stent in the treatment of atherosclerotic coronary artery lesions. Based on a non...

  6. Anesthesia and Poliomyelitis: A Matched Cohort Study.

    Science.gov (United States)

    Van Alstine, Luke W; Gunn, Paul W; Schroeder, Darrell R; Hanson, Andrew C; Sorenson, Eric J; Martin, David P

    2016-06-01

    Poliomyelitis is a viral infectious disease caused by 1 of the 3 strains of poliovirus. The World Health Organization launched an eradication campaign in 1988. Although the number of cases of poliomyelitis has drastically declined, eradication has not yet been achieved, and there are a substantial number of survivors of the disease. Survivors of poliomyelitis present a unique set of challenges to the anesthesiologist. The scientific literature regarding the anesthetic management of survivors of poliomyelitis, however, is limited and primarily experiential in nature. Using a retrospective, matched cohort study, we sought to more precisely characterize the anesthetic implications of poliomyelitis and to determine what risks, if any, may be present for patients with a history of the disease. Using the Mayo Clinic Life Sciences System Data Discovery and Query Builder, study subjects were identified as those with a history of paralytic poliomyelitis who had undergone major surgery at Mayo Clinic Rochester between 2005 and 2009. For each case, 2 sex- and age-matched controls that underwent the same surgical procedure during the study period were randomly selected from a pool of possible controls. Medical records were manually interrogated with respect to demographic variables, comorbid conditions, operative and anesthetic course, and postoperative course. We analyzed 100 cases with 2:1 matched controls and found that the peri- and postoperative courses were very similar for both groups of patients. Pain scores, postanesthesia care unit admission, length of postanesthesia care unit stay, intensive care unit admission, length of intensive care unit stay, and initial extubation location were not significantly different between the 2 groups. Looking at pulmonary complications in our primary outcome, there was no significant difference between the 2 groups (17% vs 14% for polio versus control, respectively; conditional logistic regression odds ratio = 1.5; 95% confidence

  7. Cohort Profile: Antiretroviral Therapy Cohort Collaboration (ART-CC)

    Science.gov (United States)

    May, Margaret T; Ingle, Suzanne M; Costagliola, Dominique; Justice, Amy C; de Wolf, Frank; Cavassini, Matthias; D’Arminio Monforte, Antonella; Casabona, Jordi; Hogg, Robert S; Mocroft, Amanda; Lampe, Fiona C; Dabis, François; Fätkenheuer, Gerd; Sterling, Timothy R; del Amo, Julia; Gill, M John; Crane, Heidi M; Saag, Michael S; Guest, Jodie; Brodt, Hans-Reinhard; Sterne, Jonathan AC

    2014-01-01

    The advent of effective combination antiretroviral therapy (ART) in 1996 resulted in fewer patients experiencing clinical events, so that some prognostic analyses of individual cohort studies of human immunodeficiency virus-infected individuals had low statistical power. Because of this, the Antiretroviral Therapy Cohort Collaboration (ART-CC) of HIV cohort studies in Europe and North America was established in 2000, with the aim of studying the prognosis for clinical events in acquired immune deficiency syndrome (AIDS) and the mortality of adult patients treated for HIV-1 infection. In 2002, the ART-CC collected data on more than 12,000 patients in 13 cohorts who had begun combination ART between 1995 and 2001. Subsequent updates took place in 2004, 2006, 2008, and 2010. The ART-CC data base now includes data on more than 70 000 patients participating in 19 cohorts who began treatment before the end of 2009. Data are collected on patient demographics (e.g. sex, age, assumed transmission group, race/ethnicity, geographical origin), HIV biomarkers (e.g. CD4 cell count, plasma viral load of HIV-1), ART regimen, dates and types of AIDS events, and dates and causes of death. In recent years, additional data on co-infections such as hepatitis C; risk factors such as smoking, alcohol and drug use; non-HIV biomarkers such as haemoglobin and liver enzymes; and adherence to ART have been collected whenever available. The data remain the property of the contributing cohorts, whose representatives manage the ART-CC via the steering committee of the Collaboration. External collaboration is welcomed. Details of contacts are given on the ART-CC website (www.art-cohort-collaboration.org). PMID:23599235

  8. Mortality in patients with psoriasis. A retrospective cohort study.

    Science.gov (United States)

    Masson, Walter; Rossi, Emiliano; Galimberti, María Laura; Krauss, Juan; Navarro Estrada, José; Galimberti, Ricardo; Cagide, Arturo

    2017-06-07

    The immune and inflammatory pathways involved in psoriasis could favor the development of atherosclerosis, consequently increasing mortality. The objectives of this study were: 1) to assess the mortality of a population with psoriasis compared to a control group, and 2) to assess the prevalence of cardiovascular risk factors. A retrospective cohort was analyzed from a secondary database (electronic medical record). All patients with a diagnosis of psoriasis at 1-01-2010 were included in the study and compared to a control group of the same health system, selected randomly (1:1). Subjects with a history of cardiovascular disease were excluded from the study. A survival analysis was performed considering death from any cause as an event. Follow-up was extended until 30-06-2015. We included 1,481 subjects with psoriasis and 1,500 controls. Prevalence of cardiovascular risk factors was higher in the group with psoriasis. The average follow-up time was 4.6±1.7 years. Mortality was higher in psoriasis patients compared to controls (15.1 vs. 9.6 events per 1,000 person-year, PPsoriasis was seen to be significantly associated with increased mortality rates compared to the control group in the univariate analysis (HR 1.58, 95% CI 1.16-2.15, P=.004) and after adjusting for cardiovascular risk factors (HR 1.48, 95% CI 1.08-2.3, P=.014). In this population, patients with psoriasis showed a higher prevalence for the onset of cardiovascular risk factors as well as higher mortality rates during follow-up. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

  9. Placental concentrations of heavy metals in a mother-child cohort

    Energy Technology Data Exchange (ETDEWEB)

    Amaya, E., E-mail: eamayag@ugr.es [Laboratory of Medical Investigations, San Cecilio University Hospital, University of Granada, 18071 Granada (Spain); Gil, F. [Department of Legal Medicine, Toxicology and Physic Anthropology, Faculty of Medicine, University of Granada, 18071 Granada (Spain); Freire, C. [Laboratory of Medical Investigations, San Cecilio University Hospital, University of Granada, 18071 Granada (Spain); National School of Public Health, Oswaldo Cruz Foundation (FIOCRUZ), 21041-210 Rio de Janeiro (Brazil); Olmedo, P. [Department of Legal Medicine, Toxicology and Physic Anthropology, Faculty of Medicine, University of Granada, 18071 Granada (Spain); Fernandez-Rodriguez, M. [Laboratory of Medical Investigations, San Cecilio University Hospital, University of Granada, 18071 Granada (Spain); Fernandez, M.F.; Olea, N. [Laboratory of Medical Investigations, San Cecilio University Hospital, University of Granada, 18071 Granada (Spain); CIBER de Epidemiologia y Salud Publica (CIBERESP) (Spain)

    2013-01-15

    Heavy metals are environmental contaminants with properties known to be toxic for wildlife and humans. Despite strong concerns about their harmful effects, little information is available on intrauterine exposure in humans. The aim of this study was to evaluate prenatal exposure to As, Cd, Cr, Hg, Mn, and Pb and its association with maternal factors in a population-based mother-child cohort in Southern Spain. Between 2000 and 2002, 700 pregnant women were recruited and 137 placentas from the cohort were randomly selected and analyzed for the selected metals by atomic absorption. Maternal sociodemographic and lifestyle factors were obtained by questionnaire after delivery. Bivariate analysis and multivariate linear regression were performed. Cd and Mn concentrations were detected in all placentas, while Cr, Pb, and Hg were found in 98.5%, 35.0%, and 30.7% of samples, respectively. The highest concentrations were observed for Pb (mean: 94.80 ng/g wet weight of placenta), followed by Mn (63.80 ng/g), Cr (63.70 ng/g), Cd (3.45 ng/g), and Hg (0.024 ng/g). Arsenic was not detected in any sample. Gestational age and smoking during pregnancy were associated with placental Cd concentrations, while no factor appeared to influence concentrations of Cr, Hg, Mn, or Pb. In comparison to results of European studies, these concentrations are in a low-intermediate position. Studies are required to investigate the factors contributing to early exposure to heavy metals and to determine how placental transfer of these toxic compounds may affect children's health.

  10. Placental concentrations of heavy metals in a mother–child cohort

    International Nuclear Information System (INIS)

    Amaya, E.; Gil, F.; Freire, C.; Olmedo, P.; Fernández-Rodríguez, M.; Fernández, M.F.; Olea, N.

    2013-01-01

    Heavy metals are environmental contaminants with properties known to be toxic for wildlife and humans. Despite strong concerns about their harmful effects, little information is available on intrauterine exposure in humans. The aim of this study was to evaluate prenatal exposure to As, Cd, Cr, Hg, Mn, and Pb and its association with maternal factors in a population-based mother–child cohort in Southern Spain. Between 2000 and 2002, 700 pregnant women were recruited and 137 placentas from the cohort were randomly selected and analyzed for the selected metals by atomic absorption. Maternal sociodemographic and lifestyle factors were obtained by questionnaire after delivery. Bivariate analysis and multivariate linear regression were performed. Cd and Mn concentrations were detected in all placentas, while Cr, Pb, and Hg were found in 98.5%, 35.0%, and 30.7% of samples, respectively. The highest concentrations were observed for Pb (mean: 94.80 ng/g wet weight of placenta), followed by Mn (63.80 ng/g), Cr (63.70 ng/g), Cd (3.45 ng/g), and Hg (0.024 ng/g). Arsenic was not detected in any sample. Gestational age and smoking during pregnancy were associated with placental Cd concentrations, while no factor appeared to influence concentrations of Cr, Hg, Mn, or Pb. In comparison to results of European studies, these concentrations are in a low-intermediate position. Studies are required to investigate the factors contributing to early exposure to heavy metals and to determine how placental transfer of these toxic compounds may affect children's health.

  11. Topics in random walks in random environment

    International Nuclear Information System (INIS)

    Sznitman, A.-S.

    2004-01-01

    Over the last twenty-five years random motions in random media have been intensively investigated and some new general methods and paradigms have by now emerged. Random walks in random environment constitute one of the canonical models of the field. However in dimension bigger than one they are still poorly understood and many of the basic issues remain to this day unresolved. The present series of lectures attempt to give an account of the progresses which have been made over the last few years, especially in the study of multi-dimensional random walks in random environment with ballistic behavior. (author)

  12. The Patient Deficit Model Overturned: a qualitative study of patients' perceptions of invitation to participate in a randomized controlled trial comparing selective bladder preservation against surgery in muscle invasive bladder cancer (SPARE, CRUK/07/011

    Directory of Open Access Journals (Sweden)

    Moynihan Clare

    2012-11-01

    Full Text Available Abstract Background Evidence suggests that poor recruitment into clinical trials rests on a patient ‘deficit’ model – an inability to comprehend trial processes. Poor communication has also been cited as a possible barrier to recruitment. A qualitative patient interview study was included within the feasibility stage of a phase III non-inferiority Randomized Controlled Trial (RCT (SPARE, CRUK/07/011 in muscle invasive bladder cancer. The aim was to illuminate problems in the context of randomization. Methods The qualitative study used a ‘Framework Analysis’ that included ‘constant comparison’ in which semi-structured interviews are transcribed, analyzed, compared and contrasted both between and within transcripts. Three researchers coded and interpreted data. Results Twenty-four patients agreed to enter the interview study; 10 decliners of randomization and 14 accepters, of whom 2 subsequently declined their allocated treatment. The main theme applying to the majority of the sample was confusion and ambiguity. There was little indication that confusion directly impacted on decisions to enter the SPARE trial. However, confusion did appear to impact on ethical considerations surrounding ‘informed consent’, as well as cause a sense of alienation between patients and health personnel. Sub-optimal communication in many guises accounted for the confusion, together with the logistical elements of a trial that involved treatment options delivered in a number of geographical locations. Conclusions These data highlight the difficulty of providing balanced and clear trial information within the UK health system, despite best intentions. Involvement of multiple professionals can impact on communication processes with patients who are considering participation in RCTs. Our results led us to question the ‘deficit’ model of patient behavior. It is suggested that health professionals might consider facilitating a context in which patients

  13. Predicting readmission risk of patients with diabetes hospitalized for cardiovascular disease: a retrospective cohort study.

    Science.gov (United States)

    Rubin, Daniel J; Golden, Sherita Hill; McDonnell, Marie E; Zhao, Huaqing

    2017-08-01

    To develop and validate a tool that predicts 30d readmission risk of patients with diabetes hospitalized for cardiovascular disease (CVD), the Diabetes Early Readmission Risk Indicator-CVD (DERRI-CVD™). A cohort of 8189 discharges was retrospectively selected from electronic records of adult patients with diabetes hospitalized for CVD. Discharges of 60% of the patients (n=4950) were randomly selected as a training sample and the remaining 40% (n=3219) were the validation sample. Statistically significant predictors of all-cause 30d readmission risk were identified by multivariable logistic regression modeling: education level, employment status, living within 5miles of the hospital, pre-admission diabetes therapy, macrovascular complications, admission serum creatinine and albumin levels, having a hospital discharge within 90days pre-admission, and a psychiatric diagnosis. Model discrimination and calibration were good (C-statistic 0.71). Performance in the validation sample was comparable. Predicted 30d readmission risk was similar in the training and validation samples (38.6% and 35.1% in the highest quintiles). The DERRI-CVD™ may be a valid tool to predict all-cause 30d readmission risk of patients with diabetes hospitalized for CVD. Identifying high-risk patients may encourage the use of interventions targeting those at greatest risk, potentially leading to better outcomes and lower healthcare costs. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Cohort profile: Pacific Islands Families (PIF) growth study, Auckland, New Zealand.

    Science.gov (United States)

    Rush, E; Oliver, M; Plank, L D; Taylor, S; Iusitini, L; Jalili-Moghaddam, S; Savila, F; Paterson, J; Tautolo, E

    2016-11-02

    This article profiles a birth cohort of Pacific children participating in an observational prospective study and describes the study protocol used at ages 14-15 years to investigate how food and activity patterns, metabolic risk and family and built environment are related to rates of physical growth of Pacific children. From 2000 to 2015, the Pacific Islands Families Study has followed, from birth, the growth and development of over 1000 Pacific children born in Auckland, New Zealand. In 2014, 931 (66%) of the original cohort had field measures of body composition, blood pressure and glycated haemoglobin. A nested subsample (n=204) was drawn by randomly selecting 10 males and 10 females from each decile of body weight. These participants had measurement of body composition by dual-energy X-ray absorptiometry, food frequency, 6 min walk test and accelerometer-determined physical activity and sedentary behaviours, and blood biomarkers for metabolic disease such as diabetes. Built environment variables were generated from individual addresses. Compared to the Centres for Disease Control and Prevention (CDC) reference population with mean SD scores (SDS) of 0, this cohort of 931 14-year-olds was taller, weighed more and had a higher body mass index (BMI) (mean SDS height >0.6, weight >1.6 and BMI >1.4). 7 of 10 youth were overweight or obese. The nested-sampling frame achieved an even distribution by body weight. Cross-sectional relationships between body size, fatness and growth rate, food patterns, activity patterns, pubertal development, risks for diabetes and hypertension and the family and wider environment will be examined. In addition, analyses will investigate relationships with data collected earlier in the life course and measures of the cohort in the future. Understanding past and present influences on child growth and health will inform timely interventions to optimise future health and reduce inequalities for Pacific people. Published by the BMJ

  15. Incidence of obesity during childhood and adolescence in a large contemporary cohort.

    Science.gov (United States)

    Hughes, Adrienne R; Sherriff, Andrea; Lawlor, Debbie A; Ness, Andrew R; Reilly, John J

    2011-05-01

    Timing of obesity development during childhood and adolescence is unclear, hindering preventive strategies. The primary aim of the present study was to quantify the incidence of overweight and obesity throughout childhood and adolescence in a large contemporary cohort of English children (the Avon Longitudinal Study of Parents and Children, ALSPAC; children born 1991-1992). A secondary aim was to examine the persistence of overweight and obesity. Longitudinal data on weight and height were collected annually from age 7-15 years in the entire ALSPAC cohort (n=4283), and from 3 to 15 years in a randomly selected subsample of the cohort (n=549; 'Children in Focus' CiF). Incidence of overweight and obesity (BMI (Body mass index) at or above the 85th and 95th centiles relative to U.K. reference data) was calculated. Risk ratios (RR) for overweight and obesity at 15 years based on weight status at 3, 7, and 11 years were also calculated. In the entire cohort, four-year incidence of obesity was higher between ages 7 and 11 years than between 11 and 15 years (5.0% vs. 1.4% respectively). In the CiF sub-sample, four-year incidence of obesity was also highest during mid-childhood (age 7-11years, 6.7%), slightly lower during early childhood (3-7 years, 5.1%) and lowest during adolescence (11-15 years 1.6%). Overweight and obesity at all ages had a strong tendency to persist to age 15 years as indicated by risk ratios (95% CI (Confidence interval)) for overweight and obesity at 15 years from overweight and obesity (relative to healthy weight status) at 3 years (2.4, 1.8-3.1), 7 years (4.6, 3.6-5.8), and 11 years (9.3, 6.5-13.2). Mid-late childhood (around age 7-11 years) may merit greater attention in future obesity prevention interventions. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Cohort profile: seek, test, treat and retain United States criminal justice cohort.

    Science.gov (United States)

    Chandler, Redonna; Gordon, Michael S; Kruszka, Bridget; Strand, Lauren N; Altice, Frederick L; Beckwith, Curt G; Biggs, Mary L; Cunningham, William; Chris Delaney, J A; Flynn, Patrick M; Golin, Carol E; Knight, Kevin; Kral, Alex H; Kuo, Irene; Lorvick, Jennifer; Nance, Robin M; Ouellet, Lawrence J; Rich, Josiah D; Sacks, Stanley; Seal, David; Spaulding, Anne; Springer, Sandra A; Taxman, Faye; Wohl, David; Young, Jeremy D; Young, Rebekah; Crane, Heidi M

    2017-05-16

    The STTR treatment cascade provides a framework for research aimed at improving the delivery of services, care and outcomes of PLWH. The development of effective approaches to increase HIV diagnoses and engage PLWH in subsequent steps of the treatment cascade could lead to earlier and sustained ART treatment resulting in viral suppression. There is an unmet need for research applying the treatment cascade to improve outcomes for those with criminal justice involvement. The Seek, Test, Treat, and Retain (STTR) criminal justice (CJ) cohort combines data from 11 studies across the HIV treatment cascade that focused on persons involved in the criminal justice system, often but not exclusively for reasons related to substance use. The studies were conducted in a variety of CJ settings and collected information across 11 pre-selected domains: demographic characteristics, CJ involvement, HIV risk behaviors, HIV and/or Hepatitis C infections, laboratory measures of CD4 T-cell count (CD4) and HIV RNA viral load (VL), mental illness, health related quality of life (QoL), socioeconomic status, health care access, substance use, and social support. The STTR CJ cohort includes data on 11,070 individuals with and without HIV infection who range in age from 18 to 77 years, with a median age at baseline of 37 years. The cohort reflects racial, ethnic and gender distributions in the U.S. CJ system, and 64% of participants are African-American, 12% are Hispanic and 83% are men. Cohort members reported a wide range of HIV risk behaviors including history of injection drug use and, among those who reported on pre-incarceration sexual behaviors, the prevalence of unprotected sexual intercourse ranged across studies from 4% to 79%. Across all studies, 53% percent of the STTR CJ cohort reported recent polysubstance use. The STTR CJ cohort is comprised of participants from a wide range of CJ settings including jail, prison, and community supervision who report considerable diversity in

  17. The Netherlands Cohort Study−Meat Investigation Cohort; a population-based cohort over-represented with vegetarians, pescetarians and low meat consumers.

    Science.gov (United States)

    Gilsing, Anne M J; Weijenberg, Matty P; Goldbohm, R Alexandra; Dagnelie, Pieter C; van den Brandt, Piet A; Schouten, Leo J

    2013-11-29

    Vegetarian diets have been associated with lower risk of chronic disease, but little is known about the health effects of low meat diets and the reliability of self-reported vegetarian status. We aimed to establish an analytical cohort over-represented with vegetarians, pescetarians and 1 day/week meat consumers, and to describe their lifestyle and dietary characteristics. In addition, we were able to compare self-reported vegetarians with vegetarians whose status has been confirmed by their response on the extensive food frequency questionnaire (FFQ). Embedded within the Netherlands Cohort Study (n = 120,852; including 1150 self-reported vegetarians), the NLCS-Meat Investigation Cohort (NLCS-MIC) was defined by combining all FFQ-confirmed-vegetarians (n = 702), pescetarians (n = 394), and 1 day/week meat consumers (n = 1,396) from the total cohort with a random sample of 2-5 days/week- and 6-7 days/week meat consumers (n = 2,965 and 5,648, respectively). Vegetarians, pescetarians, and 1 day/week meat consumers had more favorable dietary intakes (e.g., higher fiber/vegetables) and lifestyle characteristics (e.g. lower smoking rates) compared to regular meat consumers in both sexes. Vegetarians adhered to their diet longer than pescetarians and 1 day/week meat consumers. 75% of vegetarians with a prevalent cancer at baseline had changed to this diet after diagnosis. 50% of self-reported vegetarians reported meat or fish consumption on the FFQ. Although the misclassification that occurred in terms of diet and lifestyle when merely relying on self-reporting was relatively small, the impact on associations with disease risk remains to be studied. We established an analytical cohort over-represented with persons at the lower end of the meat consumption spectrum which should facilitate prospective studies of major cancers and causes of death using ≥20.3 years of follow-up.

  18. RANDOM WALK HYPOTHESIS IN FINANCIAL MARKETS

    Directory of Open Access Journals (Sweden)

    Nicolae-Marius JULA

    2017-05-01

    Full Text Available Random walk hypothesis states that the stock market prices do not follow a predictable trajectory, but are simply random. If you are trying to predict a random set of data, one should test for randomness, because, despite the power and complexity of the used models, the results cannot be trustworthy. There are several methods for testing these hypotheses and the use of computational power provided by the R environment makes the work of the researcher easier and with a cost-effective approach. The increasing power of computing and the continuous development of econometric tests should give the potential investors new tools in selecting commodities and investing in efficient markets.

  19. Fragmentation of random trees

    International Nuclear Information System (INIS)

    Kalay, Z; Ben-Naim, E

    2015-01-01

    We study fragmentation of a random recursive tree into a forest by repeated removal of nodes. The initial tree consists of N nodes and it is generated by sequential addition of nodes with each new node attaching to a randomly-selected existing node. As nodes are removed from the tree, one at a time, the tree dissolves into an ensemble of separate trees, namely, a forest. We study statistical properties of trees and nodes in this heterogeneous forest, and find that the fraction of remaining nodes m characterizes the system in the limit N→∞. We obtain analytically the size density ϕ s of trees of size s. The size density has power-law tail ϕ s ∼s −α with exponent α=1+(1/m). Therefore, the tail becomes steeper as further nodes are removed, and the fragmentation process is unusual in that exponent α increases continuously with time. We also extend our analysis to the case where nodes are added as well as removed, and obtain the asymptotic size density for growing trees. (paper)

  20. Random ancestor trees

    International Nuclear Information System (INIS)

    Ben-Naim, E; Krapivsky, P L

    2010-01-01

    We investigate a network growth model in which the genealogy controls the evolution. In this model, a new node selects a random target node and links either to this target node, or to its parent, or to its grandparent, etc; all nodes from the target node to its most ancient ancestor are equiprobable destinations. The emerging random ancestor tree is very shallow: the fraction g n of nodes at distance n from the root decreases super-exponentially with n, g n = e −1 /(n − 1)!. We find that a macroscopic hub at the root coexists with highly connected nodes at higher generations. The maximal degree of a node at the nth generation grows algebraically as N 1/β n , where N is the system size. We obtain the series of nontrivial exponents which are roots of transcendental equations: β 1 ≅1.351 746, β 2 ≅1.682 201, etc. As a consequence, the fraction p k of nodes with degree k has an algebraic tail, p k ∼ k −γ , with γ = β 1 + 1 = 2.351 746

  1. Competing events and costs of clinical trials: Analysis of a randomized trial in prostate cancer

    International Nuclear Information System (INIS)

    Zakeri, Kaveh; Rose, Brent S.; D’Amico, Anthony V.; Jeong, Jong-Hyeon; Mell, Loren K.

    2015-01-01

    Background: Clinical trial costs may be reduced by identifying enriched subpopulations of patients with favorable risk profiles for the events of interest. However, increased selectivity affects accrual rates, with uncertain impact on clinical trial cost. Methods: We conducted a secondary analysis of Southwest Oncology Group (SWOG) 8794 randomized trial of adjuvant radiotherapy for high-risk prostate cancer. The primary endpoint was metastasis-free survival (MFS), defined as time to metastasis or death from any cause (competing mortality). We used competing risks regression models to identify an enriched subgroup at high risk for metastasis and low risk for competing mortality. We applied a cost model to estimate the impact of enrichment on trial cost and duration. Results: The treatment effect on metastasis was similar in the enriched subgroup (HR, 0.42; 95% CI, 0.23–0.76) compared to the whole cohort (HR, 0.50; 95% CI, 0.30–0.81) while the effect on competing mortality was not significant in the subgroup or the whole cohort (HR 0.70; 95% CI 0.39–1.23, vs. HR 0.94; 95% CI, 0.68–1.31). Due to the higher incidence of metastasis relative to competing mortality in the enriched subgroup, the treatment effect on MFS was greater in the subgroup compared to the whole cohort (HR 0.55; 95% CI 0.36–0.82, vs. HR 0.77; 95% CI, 0.58–1.01). Trial cost was 75% less in the subgroup compared to the whole cohort ($1.7 million vs. $6.8 million), and the trial duration was 30% shorter (8.4 vs. 12.0 years). Conclusion: Competing event enrichment can reduce clinical trial cost and duration, without sacrificing generalizability

  2. Lung cancer risk comparison among male smokers between the "six-prefecture cohort" in Japan and the British physicians' cohort.

    Science.gov (United States)

    Mizuno, S; Akiba, S; Hirayama, T

    1989-12-01

    We estimated the effective duration of cigarette smoking using the data of lung cancer mortality among male smokers of a large-scale cohort study in Japan and evaluated its role in the lung cancer risk difference between male smokers of the Japanese cohort and the British physicians' cohort. By selecting male cohort members who answered that they had started smoking at ages 18-22 (average = 20.3), the subjects of our analysis, which numbered 49,013, were made relatively homogeneous in terms of age at which smoking was started. Assuming lung cancer mortality to be proportional to the 4.5th power of the effective duration of cigarette smoking, i.e., (age-theta)4.5, as was proposed on the basis of the British cohort study by Doll and Peto, the parameter theta was estimated to be 29.4 for male smokers aged 40-64 in 1966; therefore, the estimated duration of cigarette smoking was, on average, 9.1 years (95% confidence interval = 5.8-11.6) shorter than that calculated from the reported age at which smoking was started. Our findings suggested that the low lung cancer mortality relative to daily cigarette consumption in Japan resulted from the shorter duration of cigarette smoking in the Japanese cohort, possibly due to the severe shortage of cigarettes during and shortly after World War II. Once the effective duration of cigarette smoking was adjusted, lung cancer mortality in the range of 5-34 cigarettes per day was fairly comparable to that observed among the cohort of male British physicians.

  3. Health and aging in elderly farmers: the AMI cohort

    Directory of Open Access Journals (Sweden)

    Pérès Karine

    2012-07-01

    Full Text Available Abstract Background The health of the agricultural population has been previously explored, particularly in relation to the farming exposures and among professionally active individuals. However, few studies specifically focused on health and aging among elders retired from agriculture. Yet, this population faces the long-term effects of occupational exposures and multiple difficulties related to living and aging in rural area (limited access to shops, services, and practitioners. However, these difficulties may be counter-balanced by advantages related to healthier lifestyle, richer social support and better living environment. The general aim of the AMI cohort was to study health and aging in elderly farmers living in rural area through a multidisciplinary approach, with a main focus on dementia. Methods/design The study initially included 1 002 participants, randomly selected from the Farmer Health Insurance rolls. Selection criteria were: being 65 years and older; living in rural area in Gironde (South-Western France; being retired from agriculture after at least 20 years of activity and being affiliated to the Health Insurance under own name. The study started in 2007, with two follow-up visits over 5 years. Baseline visits were conducted at home by a neuropsychologist then by a geriatrician for all cases suspected of dementia, Parkinson’s disease and depression (to confirm the diagnosis, and by a nurse for others. A large panel of data were collected through standardised questionnaires: complete neuropsychological assessment, material and social living environment, psychological transition to retirement, lifestyle (smoking, alcohol and diet, medications, disability in daily living, sensory impairments and some clinical measures (blood pressure, depression symptomatology, anxiety, visual test, anthropometry…. A blood sampling was performed with biological measurements and constitution of a biological bank, including DNA. Brain MRI

  4. An assessment of organisational justice perceptions across three generational cohorts

    Directory of Open Access Journals (Sweden)

    Ophillia Ledimo

    2015-09-01

    Full Text Available Despite several reviews of generational differences across cohorts regarding their career stages in organisations, relatively few empirical investigations have been conducted to understand these cohorts’s behaviour and perceptions. Hence there is paucity of studies that explored the generational differences on the construct organisational justice across generational cohorts. The objective of this study was to assess the differences across three generational cohorts (Millennials, Generation X, and Baby Boomers on dimensions of the organisational justice construct using the Organisational Justice Measurement Instrument (OJMI. Data was collected through the administration of OJMI to a random sample size of organisational employees (n=289. Descriptive statistics and analysis of variance were conducted to interpret the data. These findings provide evidence that differences do exist across cohorts on dimensions of organisational justice, and some differences may be a result of respondents’ different perception of their organisation’s practices and processes. In terms of contributions and practical implications, insight gained from the findings may be used in proposing organisational development interventions to manage multigenerational employees as well as to conduct future research.

  5. Random survival forests for competing risks

    DEFF Research Database (Denmark)

    Ishwaran, Hemant; Gerds, Thomas A; Kogalur, Udaya B

    2014-01-01

    We introduce a new approach to competing risks using random forests. Our method is fully non-parametric and can be used for selecting event-specific variables and for estimating the cumulative incidence function. We show that the method is highly effective for both prediction and variable selection...

  6. Subclinical Hyperthyroidism-A Cohort Study

    International Nuclear Information System (INIS)

    Hashim, R.; Anwer, M. S.; Khan, F. A.; Ijaz, A.

    2013-01-01

    Objective: To compare the development of overt hyperthyroidism in a cohort of patients of subclinical hyperthyroidism (SCR) and in subjects with normal thyroid function tests. Study Design: A cohort study. Place and Duration of study: The study was conducted in the department of Chemical Pathology and Endocrinology, Armed Forces Institute of Pathology, Rawalpindi from Sept 2006 to Sept 2007. Patients and Methods: Fifty patients of SCR and almost equal number of age and sex-matched subjects with normal Thyroid function test (TFT) were included in the study as controls. Subclinical hyperthyroid patients and controls were followed for a period of one year on a six monthly basis. The patients were examined for signs and symptoms of hyperthyroidism and serum TSH, total T3 and free T4 were estimated. The clinical history, physical examination and TFT results were recorded. Five ml of blood was collected for serum thyroid profile in plain tube. Hormonal analysis(TSH, T4 and T3) was done for the patients and the controls enrolled in the study. The TFTs was analyzed using Chemiluminescence Immunoassay technique on Immulite 2000 an automated, random access, immunoassay analyzer. Results: Six (12%) out of 50 cases of the SCR patients and 2 (4%) out of 50 controls developed overt hyperthyroidism. SCR had no significant risk for conversion to overt hyperthyroidism as compared to healthy controls in this study. In addition to initial levels of serum TSH were one of important predictor for conversion of SCR to overt hyperthyroidism. Conclusion: Patients with SCR have no significant risk but showed an increase in frequency of conversion to overt hyperthyroidism (12% in this study) as compared to controls. (author)

  7. Design, methods and demographics from phase I of Alberta's Tomorrow Project cohort: a prospective cohort profile.

    Science.gov (United States)

    Robson, Paula J; Solbak, Nathan M; Haig, Tiffany R; Whelan, Heather K; Vena, Jennifer E; Akawung, Alianu K; Rosner, William K; Brenner, Darren R; Cook, Linda S; Csizmadi, Ilona; Kopciuk, Karen A; McGregor, S Elizabeth; Friedenreich, Christine M

    2016-01-01

    Prospective cohorts have the potential to support multifactorial, health-related research, particularly if they are drawn from the general population, incorporate active and passive follow-up and permission is obtained to allow access by researchers to data repositories. This paper describes Phase I of the Alberta's Tomorrow Project cohort, a broad-based research platform designed to support investigations into factors that influence cancer and chronic disease risk. Adults aged 35-69 years living in Alberta, Canada, with no previous cancer diagnosis other than nonmelanoma skin cancer were recruited to the project by telephone-based random digit dialling. Participants were enrolled if they returned a Health and Lifestyle Questionnaire. Past year diet and physical activity questionnaires were mailed 3 months after enrolment. Consent was sought for active follow-up and linkage with administrative databases. Depending on enrolment date, participants were invited to complete up to 2 follow-up questionnaires (2004 and 2008). Between 2001 and 2009, 31 072 (39% men) participants (mean age 50.2 [± 9.2] yr) were enrolled and 99% consented to linkage with administrative databases. Participants reported a wide range of educational attainment and household income. Compared with provincial surveillance data from the Canadian Community Health Survey, Alberta's Tomorrow Project participants had higher body mass index, lower prevalence of smoking and similar distribution of chronic health conditions. Follow-up questionnaires were completed by 83% and 72% of participants in 2004 and 2008, respectively. Robust quality control measures resulted in low frequencies of missing data. Alberta's Tomorrow Project provides a robust platform, based on a prospective cohort design, to support research into risk factors for cancer and chronic disease.

  8. CONCLUSIONS New Delhi Birth Cohort

    Indian Academy of Sciences (India)

    CONCLUSIONS New Delhi Birth Cohort. Crossing BMI centiles and early adiposity rebound associated with adult metabolic syndrome. BMI gain in infancy and early childhood – associated more with adult lean mass. BMI gain in later childhood / adolescence – associated more with adult fat mass and constituents of ...

  9. Cohort Default Rates in Context

    Science.gov (United States)

    Looney, Shannon M.

    2011-01-01

    Burgeoning student loan debt indicates problems not only for the country's borrowers but also for the postsecondary system. The rise in student loan defaults signifies a rise in institutional cohort default rates (CDRs)--a measure of accountability that informs the government and the general public how well an institution prepares its students for…

  10. Evaluation of physiotherapy in a prospective cohort of early axial spondyloarthritis. Data from the DESIR cohort.

    Science.gov (United States)

    Escalas, Cécile; Dalichampt, Marie; Dougados, Maxime; Poiraudeau, Serge

    2016-03-01

    To evaluate the effect of physiotherapy on functional limitation in an observational cohort of early axial spondyloarthritis. prospective population-based cohort study. 708 patients with early axial spondyloarthritis between 2007 and 2010 naive of TNF blockers. early physiotherapy defined by at least eight supervised sessions of physical therapy during the first six months. the primary outcome was functional improvement defined by a relative improvement of at least 20% in BASFI at six months. Secondary outcomes were improvement in BASFI at one and two years and ASAS20 response criteria at six months. a propensity score of having physiotherapy was developed and multivariate analysis using propensity score weighting were used to assess the effect of physiotherapy on outcome. Overall, 166 (24%) patients had physiotherapy during the first six months. After using propensity score weighting, there was no functional improvement on the primary outcome in patients treated with early physical therapy (relative risk [IC95%]: 1.15 [0.91-1.45]). No differences were observed on secondary outcomes (relative risk [IC95%]: 0.94 [0.80-1.11]). It seems there is no functional benefit for patients with early spondyloarthritis to be treated early by physiotherapy in daily practice, even though the efficacy of physiotherapy has been shown in several randomized controlled studies. Copyright © 2015 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.

  11. Biomarker analyses and final overall survival results from a phase III, randomized, open-label, first-line study of gefitinib versus carboplatin/paclitaxel in clinically selected patients with advanced non-small-cell lung cancer in Asia (IPASS).

    Science.gov (United States)

    Fukuoka, Masahiro; Wu, Yi-Long; Thongprasert, Sumitra; Sunpaweravong, Patrapim; Leong, Swan-Swan; Sriuranpong, Virote; Chao, Tsu-Yi; Nakagawa, Kazuhiko; Chu, Da-Tong; Saijo, Nagahiro; Duffield, Emma L; Rukazenkov, Yuri; Speake, Georgina; Jiang, Haiyi; Armour, Alison A; To, Ka-Fai; Yang, James Chih-Hsin; Mok, Tony S K

    2011-07-20

    The results of the Iressa Pan-Asia Study (IPASS), which compared gefitinib and carboplatin/paclitaxel in previously untreated never-smokers and light ex-smokers with advanced pulmonary adenocarcinoma were published previously. This report presents overall survival (OS) and efficacy according to epidermal growth factor receptor (EGFR) biomarker status. In all, 1,217 patients were randomly assigned. Biomarkers analyzed were EGFR mutation (amplification mutation refractory system; 437 patients evaluable), EGFR gene copy number (fluorescent in situ hybridization; 406 patients evaluable), and EGFR protein expression (immunohistochemistry; 365 patients evaluable). OS analysis was performed at 78% maturity. A Cox proportional hazards model was used to assess biomarker status by randomly assigned treatment interactions for progression-free survival (PFS) and OS. OS (954 deaths) was similar for gefitinib and carboplatin/paclitaxel with no significant difference between treatments overall (hazard ratio [HR], 0.90; 95% CI, 0.79 to 1.02; P = .109) or in EGFR mutation-positive (HR, 1.00; 95% CI, 0.76 to 1.33; P = .990) or EGFR mutation-negative (HR, 1.18; 95% CI, 0.86 to 1.63; P = .309; treatment by EGFR mutation interaction P = .480) subgroups. A high proportion (64.3%) of EGFR mutation-positive patients randomly assigned to carboplatin/paclitaxel received subsequent EGFR tyrosine kinase inhibitors. PFS was significantly longer with gefitinib for patients whose tumors had both high EGFR gene copy number and EGFR mutation (HR, 0.48; 95% CI, 0.34 to 0.67) but significantly shorter when high EGFR gene copy number was not accompanied by EGFR mutation (HR, 3.85; 95% CI, 2.09 to 7.09). EGFR mutations are the strongest predictive biomarker for PFS and tumor response to first-line gefitinib versus carboplatin/paclitaxel. The predictive value of EGFR gene copy number was driven by coexisting EGFR mutation (post hoc analysis). Treatment-related differences observed for PFS in the EGFR

  12. Nonlinear Pricing with Random Participation

    OpenAIRE

    Jean-Charles Rochet; Lars A. Stole

    2002-01-01

    The canonical selection contracting programme takes the agent's participation decision as deterministic and finds the optimal contract, typically satisfying this constraint for the worst type. Upon weakening this assumption of known reservation values by introducing independent randomness into the agents' outside options, we find that some of the received wisdom from mechanism design and nonlinear pricing is not robust and the richer model which allows for stochastic participation affords a m...

  13. Early mortality after radical radiotherapy for non-small-cell lung cancer: comparison of PET-staged and conventionally staged cohorts treated at a large tertiary referral center

    International Nuclear Information System (INIS)

    Mac Manus, Michael P.; Wong, Kevin; Hicks, Rodney J.; Matthews, Jane P.; Wirth, Andrew; Ball, David L.

    2002-01-01

    Purpose: At our center, approximately 30% of radical radiotherapy (RRT) candidates become ineligible for RRT for non-small-cell lung cancer (NSCLC) after positron emission tomography (PET). We hypothesized that early cancer death rates would be lower in patients receiving RRT after PET staging compared with conventionally staged patients. Methods and Materials: Two prospective cohorts were compared. Cohort 1 consisted of all participants in an Australian randomized trial from our center given 60 Gy conventionally fractionated RRT with or without concurrent carboplatin from 1989 to 1995. Eligible patients had Stage I-III, Eastern Cooperative Oncology Group status 0 or 1, <10% weight loss, and had not undergone PET. Cohort 2 included all RRT candidates between November 1996 and April 1999 who received RRT after PET staging and fulfilled the above criteria for stage, Eastern Cooperative Oncology Group status, and weight loss. Results: Eighty and 77 eligible patients comprised the PET and non-PET groups, respectively. The PET-selected patients had significantly less weight loss; 73% and 49% of the PET and non-PET patients, respectively, received chemotherapy. The median survival was 31 months for PET patients and 16 months for non-PET patients. Mortality from NSCLC and other causes in the first year was 17% and 8% for PET patients and 32% and 4% for non-PET patients, respectively. The hazard ratio for NSCLC mortality for PET vs. non-PET patients was 0.49 (p=0.0016) on unifactorial analysis and was 0.55 (p = 0.0075) after adjusting for chemotherapy, which significantly improved survival. Conclusion: Patients selected for RRT after PET have lower early cancer mortality than those selected using conventional imaging

  14. Random broadcast on random geometric graphs

    Energy Technology Data Exchange (ETDEWEB)

    Bradonjic, Milan [Los Alamos National Laboratory; Elsasser, Robert [UNIV OF PADERBORN; Friedrich, Tobias [ICSI/BERKELEY; Sauerwald, Tomas [ICSI/BERKELEY

    2009-01-01

    In this work, we consider the random broadcast time on random geometric graphs (RGGs). The classic random broadcast model, also known as push algorithm, is defined as: starting with one informed node, in each succeeding round every informed node chooses one of its neighbors uniformly at random and informs it. We consider the random broadcast time on RGGs, when with high probability: (i) RGG is connected, (ii) when there exists the giant component in RGG. We show that the random broadcast time is bounded by {Omicron}({radical} n + diam(component)), where diam(component) is a diameter of the entire graph, or the giant component, for the regimes (i), or (ii), respectively. In other words, for both regimes, we derive the broadcast time to be {Theta}(diam(G)), which is asymptotically optimal.

  15. Quantumness, Randomness and Computability

    International Nuclear Information System (INIS)

    Solis, Aldo; Hirsch, Jorge G

    2015-01-01

    Randomness plays a central role in the quantum mechanical description of our interactions. We review the relationship between the violation of Bell inequalities, non signaling and randomness. We discuss the challenge in defining a random string, and show that algorithmic information theory provides a necessary condition for randomness using Borel normality. We close with a view on incomputablity and its implications in physics. (paper)

  16. How random is a random vector?

    Science.gov (United States)

    Eliazar, Iddo

    2015-12-01

    Over 80 years ago Samuel Wilks proposed that the "generalized variance" of a random vector is the determinant of its covariance matrix. To date, the notion and use of the generalized variance is confined only to very specific niches in statistics. In this paper we establish that the "Wilks standard deviation" -the square root of the generalized variance-is indeed the standard deviation of a random vector. We further establish that the "uncorrelation index" -a derivative of the Wilks standard deviation-is a measure of the overall correlation between the components of a random vector. Both the Wilks standard deviation and the uncorrelation index are, respectively, special cases of two general notions that we introduce: "randomness measures" and "independence indices" of random vectors. In turn, these general notions give rise to "randomness diagrams"-tangible planar visualizations that answer the question: How random is a random vector? The notion of "independence indices" yields a novel measure of correlation for Lévy laws. In general, the concepts and results presented in this paper are applicable to any field of science and engineering with random-vectors empirical data.

  17. How random is a random vector?

    International Nuclear Information System (INIS)

    Eliazar, Iddo

    2015-01-01

    Over 80 years ago Samuel Wilks proposed that the “generalized variance” of a random vector is the determinant of its covariance matrix. To date, the notion and use of the generalized variance is confined only to very specific niches in statistics. In this paper we establish that the “Wilks standard deviation” –the square root of the generalized variance–is indeed the standard deviation of a random vector. We further establish that the “uncorrelation index” –a derivative of the Wilks standard deviation–is a measure of the overall correlation between the components of a random vector. Both the Wilks standard deviation and the uncorrelation index are, respectively, special cases of two general notions that we introduce: “randomness measures” and “independence indices” of random vectors. In turn, these general notions give rise to “randomness diagrams”—tangible planar visualizations that answer the question: How random is a random vector? The notion of “independence indices” yields a novel measure of correlation for Lévy laws. In general, the concepts and results presented in this paper are applicable to any field of science and engineering with random-vectors empirical data.

  18. Mixed models, linear dependency, and identification in age-period-cohort models.

    Science.gov (United States)

    O'Brien, Robert M

    2017-07-20

    This paper examines the identification problem in age-period-cohort models that use either linear or categorically coded ages, periods, and cohorts or combinations of these parameterizations. These models are not identified using the traditional fixed effect regression model approach because of a linear dependency between the ages, periods, and cohorts. However, these models can be identified if the researcher introduces a single just identifying constraint on the model coefficients. The problem with such constraints is that the results can differ substantially depending on the constraint chosen. Somewhat surprisingly, age-period-cohort models that specify one or more of ages and/or periods and/or cohorts as random effects are identified. This is the case without introducing an additional constraint. I label this identification as statistical model identification and show how statistical model identification comes about in mixed models and why which effects are treated as fixed and which are treated as random can substantially change the estimates of the age, period, and cohort effects. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  19. Cohort Profile: The Danish Testicular Cancer Late Treatment Effects Cohort (DaTeCa-LATE

    Directory of Open Access Journals (Sweden)

    Michael Kreiberg

    2018-02-01

    Full Text Available The cohort was set up in order to analyze late effects in long-term testicular cancer survivors (TCS and to contribute to the design of future follow-up programs addressing and potentially preventing late effects. Data for this cross-sectional study were collected between January 1, 2014, and December 31, 2016, among living Danish TCS and 60% agreed to participate in the cohort (N = 2,572. Mean time since testicular cancer (TC diagnosis was 18 years (range 7–33 and mean age of participants was 53 years (range 25–95. Data consist of results of a questionnaire with patient reported outcomes which covers a broad range of items on late-effects. The study also included data obtained through linkages to Danish registries, a biobank, and clinical data from hospital files and pathology reports originating from the Danish Testicular Cancer Database (DaTeCa. The treatment during the observation period has been nearly the same for all stages of TC and is in agreement with today’s standard treatment, this allows for interesting analysis with a wide timespan. We have extensive data on non-responders and are able to validate our study findings. Data from a Danish reference population (N = 162,283 allow us to compare our findings with a Danish background population. The cohort can easily be extended to access more outcomes, or include new TCS. A limitation of the present study is the cross-sectional design and despite the large sample size, The Danish Testicular Cancer Late Treatment Effects Cohort (DaTeCa-LATE lacks statistical power to study very rare late effects. Since it was voluntary to participate in the study we have some selection bias, for instance, we lack responders who were not in a paired relationship, but we would still argue that this cohort of TCSs is representative for TCSs in Denmark.Collaboration and data accessResearches interested in collaboration with the DaTeCa-LATE study group please contact Professor Gedske Daugaard

  20. Unilateral Vocal Fold Paralysis and Risk of Pneumonia: A Nationwide Population-Based Cohort Study.

    Science.gov (United States)

    Tsai, Ming-Shao; Yang, Yao-Hsu; Liu, Chia-Yen; Lin, Meng-Hung; Chang, Geng-He; Tsai, Yao-Te; Li, Hsueh-Yu; Tsai, Ying-Huang; Hsu, Cheng-Ming

    2018-05-01

    Objective To investigate pneumonia risk among patients with unilateral vocal fold paralysis (UVFP). Study Design Retrospective population-based cohort study. Setting This study used data from the National Health Insurance Research Database of Taiwan, a nationwide population-based database. Subjects and Methods A total of 419 patients newly diagnosed with UVFP between January 1, 1997, and December 31, 2013, were identified from the Longitudinal Health Insurance Database 2000, a nationally representative database of 1 million randomly selected patients. Moreover, 1676 patients without UVFP were matched to patients with UVFP at a 1:4 ratio based on age, sex, socioeconomic status, urbanization level, and site-specific cancers. Patients were followed up until death or the end of the study period (December 31, 2013). The primary outcome was the occurrence of pneumonia. Results The cumulative incidence of pneumonia was significantly higher for patients with UVFP than those without UFVP ( P < .001). The adjusted Cox proportional hazard model showed that UVFP was significantly associated with a higher incidence of pneumonia (hazard ratio, 1.97; 95% CI, 1.35-2.86; P < .001). Subgroup analyses demonstrated that UVFP was an independent risk factor of pneumonia for 4 subgroups: young (18-50 years), older (≥51 years), male, and cancer. Conclusion This is the first nationwide population-based cohort study to investigate the association between UVFP and pneumonia. The findings indicate that UVFP is an independent risk factor of pneumonia. Given the study results, physicians should be aware of the potential for pneumonia occurrence following UVFP.

  1. A case-control study of non-AIDS-defining cancers in a prospective cohort of HIV-infected patients.

    Science.gov (United States)

    Rodríguez Arrondo, Francisco; von Wichmann, Miguel Ángel; Camino, Xabier; Goenaga, Miguel Ángel; Ibarguren, Maialen; Azcune, Harkaitz; Bustinduy, María Jesús; Ferrero, Oscar; Muñoz, Josefa; Ibarra, Sofía; Aguirrebengoa, Koldo; Goicoetxea, Josune; Bereciartua, Elena; Montejo, Miguel; García, M Asunción; Martínez, Eduardo; Portu, Joseba; Metola, Luis; Silvariño, Rafael; Sarasqueta, Cristina; Arrizabalaga, Julio; Iribarren, Jose Antonio

    2018-04-23

    We present a case-control study of non-AIDS-defining cancers (NADCs) in a cohort of HIV-infected patients where we value the incidence, survival and prognostic factors of mortality. All NADCs diagnosis conducted from 2007 to 2011 in 7 hospitals were collected prospectively, with a subsequent follow up until December 2013. A control group of 221 HIV patients without a diagnosis of cancer was randomly selected. Two hundred and twenty-one NADCs were diagnosed in an initial cohort of 7,067 HIV-infected patients. The most common were: hepatocellular carcinoma 20.5%, lung 18.7%, head and neck 11.9% and anal 10.5%. The incidence rate of NADCs development was 7.84/1,000 people-year. In addition to aging and smoking, time on ART (OR 1.11; 95% CI 1.05-1.17) and PI use (OR 1.72; 95% CI 1.0-2.96) increased the risk of developing a NADC. During follow-up 53.42% died, with a median survival time of 199.5 days. In the analysis of the prognostic factors of mortality the low values of CD4 at tumour diagnosis (OR 0.99; 95% CI 0.99-1.0; P=.033), and the previous diagnosis of AIDS (OR 2.06; 95% CI 1.08-3.92) were associated with higher mortality. Predictors of NADCs in our cohort were age, smoking, CD4 lymphocytes and time on ART. Mortality is high, with NADC risk factors being low CD4 count and previous diagnosis of AIDS. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

  2. The Harbin Cohort Study on Diet, Nutrition and Chronic Non-communicable Diseases: study design and baseline characteristics.

    Directory of Open Access Journals (Sweden)

    Lixin Na

    Full Text Available Diet and nutrition have been reported to be associated with many common chronic diseases and blood-based assessment would be vital to investigate the association and mechanism, however, blood-based prospective studies are limited. The Harbin Cohort Study on Diet, Nutrition and Chronic Non-communicable Diseases was set up in 2010. From 2010 to 2012, 9,734 participants completed the baseline survey, including demographic characteristics, dietary intake, lifestyles and physical condition, and anthropometrics. A re-survey on 490 randomly selected participants was done by using the same methods which were employed in the baseline survey. For all participants, the mean age was 50 years and 36% of them were men. Approximately 99.4 % of cohort members donated blood samples. The mean total energy intake was 2671.7 kcal/day in men and 2245.9 kcal/day in women, the mean body mass index was 25.7 kg/m2 in men and 24.6 kg/m2 in women, with 18.4% being obese (≥ 28 kg/m2, 12.7% being diabetic, and 29.5% being hypertensive. A good agreement was obtained for the physical measurements between the baseline survey and re-survey. The resources from the cohort and its fasting and postprandial blood samples collected both at baseline and in each follow-up will be valuable and powerful in investigating relationship between diet, nutrition and chronic diseases and discovering novel blood biomarkers and the metabolism of these biomarkers related to chronic diseases.

  3. Age, period, or birth cohort: What determines demographic differences in seafood consumption?

    DEFF Research Database (Denmark)

    Scholderer, Joachim; Lund, Eiliv; Trondsen, Torbjørn

    Effects of age, period and birth cohort on consumption of fat fish, lean fish and processed fish were estimated based on panel data from the Norwegian Women and Seafood Consumption Study (NOWAC). Cohorts selected for the present analysis were women born between 1951 and 1966. Survey questionnaires...... fish increased between 1996 and 2001, while consumption of lean fish decreased. All three period effects were stable across birth cohorts. Estimation of polynomial contrasts indicated that birth cohort itself had linear effects on consumption, with older generations consuming significantly more fat...... and lean fish, but less processed fish than younger generations. Finally, the effects of cohort and period on consumption of lean and processed fish remained stable when biological age was controlled for, whilst the effect of period on fat fish consumption vanished. Regarding total consumption of fat fish...

  4. Separating the effects of age, period and birth cohort on seafood consumption in Norway

    DEFF Research Database (Denmark)

    Scholderer, Joachim; Trondsen, Torbjørn; Lund, Eiliv

    Effects of age, period and birth cohort on consumption of fat fish, lean fish and processed fish were estimated based on panel data from the Norwegian Women and Seafood Consumption Study (NOWAC). Cohorts selected for the present analysis were women born between 1951 and 1966. Survey questionnaires...... fish increased between 1996 and 2001, while consumption of lean fish decreased. All three period effects were stable across birth cohorts. Estimation of polynomial contrasts indicated that birth cohort itself had linear effects on consumption, with older generations consuming significantly more fat...... and lean fish, but less processed fish than younger generations. Finally, the effects of cohort and period on consumption of lean and processed fish remained stable when biological age was controlled for, whilst the effect of period on fat fish consumption vanished. Regarding total consumption of fat fish...

  5. [Selective mutism].

    Science.gov (United States)

    Ytzhak, A; Doron, Y; Lahat, E; Livne, A

    2012-10-01

    Selective mutism is an uncommon disorder in young children, in which they selectively don't speak in certain social situations, while being capable of speaking easily in other social situations. Many etiologies were proposed for selective mutism including psychodynamic, behavioral and familial etc. A developmental etiology that includes insights from all the above is gaining support. Accordingly, mild language impairment in a child with an anxiety trait may be at the root of developing selective mutism. The behavior will be reinforced by an avoidant pattern in the family. Early treatment and followup for children with selective mutism is important. The treatment includes non-pharmacological therapy (psychodynamic, behavioral and familial) and pharmacologic therapy--mainly selective serotonin reuptake inhibitors (SSRI).

  6. Anonymous non-response analysis in the ABCD cohort study enabled by probabilistic record linkage

    NARCIS (Netherlands)

    Tromp, M.; van Eijsden, M.; Ravelli, A. C. J.; Bonsel, G. J.

    2009-01-01

    Selective non-response is an important threat to study validity as it can lead to selection bias. The Amsterdam Born Children and their Development study (ABCD-study) is a large cohort study addressing the relationship between life style, psychological conditions, nutrition and sociodemographic

  7. Evaluation of cancer mortality in a cohort of workers exposed to low-level radiation

    Energy Technology Data Exchange (ETDEWEB)

    Lea, C.S.

    1995-12-01

    The purpose of this dissertation was to re-analyze existing data to explore methodologic approaches that may determine whether excess cancer mortality in the ORNL cohort can be explained by time-related factors not previously considered; grouping of cancer outcomes; selection bias due to choice of method selected to incorporate an empirical induction period; or the type of statistical model chosen.

  8. Evaluation of cancer mortality in a cohort of workers exposed to low-level radiation

    International Nuclear Information System (INIS)

    Lea, C.S.

    1995-12-01

    The purpose of this dissertation was to re-analyze existing data to explore methodologic approaches that may determine whether excess cancer mortality in the ORNL cohort can be explained by time-related factors not previously considered; grouping of cancer outcomes; selection bias due to choice of method selected to incorporate an empirical induction period; or the type of statistical model chosen

  9. Initial non-participation and loss to follow-up in a Danish youth cohort

    DEFF Research Database (Denmark)

    Winding, Trine Nøhr; Andersen, Johan H; Labriola, Merete

    2014-01-01

    BACKGROUND: Initial non-participation and loss to follow-up in the Danish youth cohort Vestliv could introduce selection bias of the measured risk estimates. OBJECTIVE: To investigate the impact of initial non-participation and loss to follow-up on the validity of descriptive measures and selected...

  10. Liver function tests and risk prediction of incident type 2 diabetes : evaluation in two independent cohorts

    NARCIS (Netherlands)

    Abbasi, Ali; Bakker, Stephan J. L.; Corpeleijn, Eva; van der A, Daphne L.; Gansevoort, Ron T.; Gans, Rijk O. B.; Peelen, Linda M.; van der Schouw, Yvonne T.; Stolk, Ronald P.; Navis, Gerjan; Spijkerman, Annemieke M. W.; Beulens, Joline W. J.

    2012-01-01

    Background: Liver function tests might predict the risk of type 2 diabetes. An independent study evaluating utility of these markers compared with an existing prediction model is yet lacking. Methods and Findings: We performed a case-cohort study, including random subcohort (6.5%) from 38,379

  11. Analysis of polymorphisms and selective pressures on ama1 gene ...

    Indian Academy of Sciences (India)

    Chuen Yang Chua

    2017-09-05

    Sep 5, 2017 ... The presence of purifying selection and low nucleotide diversity ... (2000) studied the gene substitution of ama1 ... in the gene coding for AMA-1 protein in Plasmodium ... Health Malaysia. ...... X. Asembo Bay Cohort Project.

  12. The Lausanne cohort Lc65+: a population-based prospective study of the manifestations, determinants and outcomes of frailty

    Directory of Open Access Journals (Sweden)

    Rodondi Nicolas

    2008-08-01

    Full Text Available Abstract Background Frailty is a relatively new geriatric concept referring to an increased vulnerability to stressors. Various definitions have been proposed, as well as a range of multidimensional instruments for its measurement. More recently, a frailty phenotype that predicts a range of adverse outcomes has been described. Understanding frailty is a particular challenge both from a clinical and a public health perspective because it may be a reversible precursor of functional dependence. The Lausanne cohort Lc65+ is a longitudinal study specifically designed to investigate the manifestations of frailty from its first signs in the youngest old, identify medical and psychosocial determinants, and describe its evolution and related outcomes. Methods/Design The Lc65+ cohort was launched in 2004 with the random selection of 3054 eligible individuals aged 65 to 70 (birth year 1934–1938 in the non-institutionalized population of Lausanne (Switzerland. The baseline data collection was completed among 1422 participants in 2004–2005 through questionnaires, examination and performance tests. It comprised a wide range of medical and psychosocial dimensions, including a life course history of adverse events. Outcomes measures comprise subjective health, limitations in activities of daily living, mobility impairments, development of medical conditions or chronic health problems, falls, institutionalization, health services utilization, and death. Two additional random samples of 65–70 years old subjects will be surveyed in 2009 (birth year 1939–1943 and in 2014 (birth year 1944–1948. Discussion The Lc65+ study focuses on the sequence "Determinants → Components → Consequences" of frailty. It currently provides information on health in the youngest old and will allow comparisons to be made between the profiles of aging individuals born before, during and at the end of the Second World War.

  13. Long-term efficacy of modified-release recombinant human TSH (MRrhTSH) augmented radioiodine (131I) therapy for benign multinodular goiter. Results from a multicenter international, randomized, placebo-controlled dose-selection study

    DEFF Research Database (Denmark)

    Fast, Søren; Hegedus, Laszlo; Pacini, Furio

    2014-01-01

    with 131I-therapy. Methods: In this phase II, single-blinded, placebo-controlled study, 95 patients (57.2±9.6 years old, 85% women, 83% Caucasians) with MNG (median size 96.0 ml (31.9 - 242.2 ml)) were randomized to receive placebo (n=32), 0.01 mg MRrhTSH (n=30) or 0.03 mg MRrhTSH (n=33), 24 hours before...... a calculated 131I activity. Thyroid volume (TV) and smallest cross-sectional area of trachea (SCAT) were measured (by CT-scan) at baseline, month 6 and month 36. Thyroid function and quality of life (QoL) was evaluated at 3 month and yearly intervals, respectively. Results: At 6 months, TV reduction...... was enhanced in the 0.03 mg MRrhTSH group (32.9% versus 23.1% in the placebo group, p=0.03), but not in the 0.01 mg MRrhTSH group. At month 36 the mean percent TV reduction from baseline was 44 ± 12.7% (SD) in the placebo group, 41 ± 21.0% in the 0.01 mg MRrhTSH-group and 53 ± 18.6% in the 0.03 mg MRrh...

  14. Risk for unemployment of cancer survivors: A Danish cohort study

    DEFF Research Database (Denmark)

    Carlsen, Kathrine; Dalton, Susanne Oksbjerg; Diderichsen, Finn

    2008-01-01

    AIM: To investigate whether cancer survivors are at an increased risk for unemployment after cancer. MATERIALS AND METHODS: A cohort of 65,510 patients who were part of the workforce in the year before diagnosis and a random sample of 316,925 age and gender-matched controls were followed for up...... that the risk for unemployment was highest amongst persons aged 50-60 years at time of diagnosis. Risk factors for unemployment were found to be manual work, medium income and vocational education. CONCLUSION: Generally, cancer patients were at a small increased risk for unemployment and low socioeconomic...

  15. Generational Differences In Organizational Justice Perceptions: An Exploratory Investigation Across Three Generational Cohorts

    Directory of Open Access Journals (Sweden)

    Ledimo Ophillia

    2015-06-01

    Full Text Available Despite several reviews of generational differences across cohorts regarding their career stages in organizations, relatively few empirical investigations have been conducted to understand cohorts’ perceptions. Hence, there is paucity of studies that explored differences on the construct organizational justice across generational cohorts. The objective of this study was to explore the differences across three generational cohorts (Millennials, Generation X, and Baby Boomers on dimensions of the organizational justice measurement instrument (OJMI. Data was collected through the administration of OJMI to a random sample size of organizational employees (n = 289. Descriptive statistics and analysis of variance were conducted to interpret the data. These findings provide evidence that differences do exist across cohorts on dimensions of organizational justice. In terms of contributions and practical implications, insight gained from the findings may be used in proposing organizational development interventions to manage multigenerational employees as well as to conduct future research.

  16. The effect of selection on genetic parameter estimates

    African Journals Online (AJOL)

    Unknown

    The South African Journal of Animal Science is available online at ... A simulation study was carried out to investigate the effect of selection on the estimation of genetic ... The model contained a fixed effect, random genetic and random.

  17. 47 CFR 1.1604 - Post-selection hearings.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Post-selection hearings. 1.1604 Section 1.1604 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE Random Selection Procedures for Mass Media Services General Procedures § 1.1604 Post-selection hearings. (a) Following the random...

  18. Site selection

    CERN Multimedia

    CERN PhotoLab

    1968-01-01

    To help resolve the problem of site selection for the proposed 300 GeV machine, the Council selected "three wise men" (left to right, J H Bannier of the Netherlands, A Chavanne of Switzerland and L K Boggild of Denmark).

  19. Benchmark selection

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Tvede, Mich

    2002-01-01

    Within a production theoretic framework, this paper considers an axiomatic approach to benchmark selection. It is shown that two simple and weak axioms; efficiency and comprehensive monotonicity characterize a natural family of benchmarks which typically becomes unique. Further axioms are added...... in order to obtain a unique selection...

  20. Characterization of Pharmacologic and Pharmacokinetic Properties of CCX168, a Potent and Selective Orally Administered Complement 5a Receptor Inhibitor, Based on Preclinical Evaluation and Randomized Phase 1 Clinical Study.

    Science.gov (United States)

    Bekker, Pirow; Dairaghi, Daniel; Seitz, Lisa; Leleti, Manmohan; Wang, Yu; Ertl, Linda; Baumgart, Trageen; Shugarts, Sarah; Lohr, Lisa; Dang, Ton; Miao, Shichang; Zeng, Yibin; Fan, Pingchen; Zhang, Penglie; Johnson, Daniel; Powers, Jay; Jaen, Juan; Charo, Israel; Schall, Thomas J

    2016-01-01

    The complement 5a receptor has been an attractive therapeutic target for many autoimmune and inflammatory disorders. However, development of a selective and potent C5aR antagonist has been challenging. Here we describe the characterization of CCX168 (avacopan), an orally administered selective and potent C5aR inhibitor. CCX168 blocked the C5a binding, C5a-mediated migration, calcium mobilization, and CD11b upregulation in U937 cells as well as in freshly isolated human neutrophils. CCX168 retains high potency when present in human blood. A transgenic human C5aR knock-in mouse model allowed comparison of the in vitro and in vivo efficacy of the molecule. CCX168 effectively blocked migration in in vitro and ex vivo chemotaxis assays, and it blocked the C5a-mediated neutrophil vascular endothelial margination. CCX168 was effective in migration and neutrophil margination assays in cynomolgus monkeys. This thorough in vitro and preclinical characterization enabled progression of CCX168 into the clinic and testing of its safety, tolerability, pharmacokinetic, and pharmacodynamic profiles in a Phase 1 clinical trial in 48 healthy volunteers. CCX168 was shown to be well tolerated across a broad dose range (1 to 100 mg) and it showed dose-dependent pharmacokinetics. An oral dose of 30 mg CCX168 given twice daily blocked the C5a-induced upregulation of CD11b in circulating neutrophils by 94% or greater throughout the entire day, demonstrating essentially complete target coverage. This dose regimen is being tested in clinical trials in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis. Trial Registration ISRCTN registry with trial ID ISRCTN13564773.

  1. Characterization of Pharmacologic and Pharmacokinetic Properties of CCX168, a Potent and Selective Orally Administered Complement 5a Receptor Inhibitor, Based on Preclinical Evaluation and Randomized Phase 1 Clinical Study.

    Directory of Open Access Journals (Sweden)

    Pirow Bekker

    Full Text Available The complement 5a receptor has been an attractive therapeutic target for many autoimmune and inflammatory disorders. However, development of a selective and potent C5aR antagonist has been challenging. Here we describe the characterization of CCX168 (avacopan, an orally administered selective and potent C5aR inhibitor. CCX168 blocked the C5a binding, C5a-mediated migration, calcium mobilization, and CD11b upregulation in U937 cells as well as in freshly isolated human neutrophils. CCX168 retains high potency when present in human blood. A transgenic human C5aR knock-in mouse model allowed comparison of the in vitro and in vivo efficacy of the molecule. CCX168 effectively blocked migration in in vitro and ex vivo chemotaxis assays, and it blocked the C5a-mediated neutrophil vascular endothelial margination. CCX168 was effective in migration and neutrophil margination assays in cynomolgus monkeys. This thorough in vitro and preclinical characterization enabled progression of CCX168 into the clinic and testing of its safety, tolerability, pharmacokinetic, and pharmacodynamic profiles in a Phase 1 clinical trial in 48 healthy volunteers. CCX168 was shown to be well tolerated across a broad dose range (1 to 100 mg and it showed dose-dependent pharmacokinetics. An oral dose of 30 mg CCX168 given twice daily blocked the C5a-induced upregulation of CD11b in circulating neutrophils by 94% or greater throughout the entire day, demonstrating essentially complete target coverage. This dose regimen is being tested in clinical trials in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis. Trial Registration ISRCTN registry with trial ID ISRCTN13564773.

  2. A cluster-randomized controlled trial evaluating the effects of delaying onset of adolescent substance abuse on cognitive development and addiction following a selective, personality-targeted intervention programme: the Co-Venture trial.

    Science.gov (United States)

    O'Leary-Barrett, Maeve; Mâsse, Benoit; Pihl, Robert O; Stewart, Sherry H; Séguin, Jean R; Conrod, Patricia J

    2017-10-01

    Substance use and binge drinking during early adolescence are associated with neurocognitive abnormalities, mental health problems and an increased risk for future addiction. The trial aims to evaluate the protective effects of an evidence-based substance use prevention programme on the onset of alcohol and drug use in adolescence, as well as on cognitive, mental health and addiction outcomes over 5 years. Thirty-eight high schools will be recruited, with a final sample of 31 schools assigned to intervention or control conditions (3826 youth). Brief personality-targeted interventions will be delivered to high-risk youth attending intervention schools during the first year of the trial. Control school participants will receive no intervention above what is offered to them in the regular curriculum by their respective schools. Public/private French and English high schools in Montreal (Canada). All grade 7 students (12-13 years old) will be invited to participate. High-risk youth will be identified as those scoring one standard deviation or more above the school mean on one of the four personality subscales of the Substance Use Risk Profile Scale (40-45% youth). Self-reported substance use and mental health symptoms and cognitive functioning measured annually throughout 5 years. Primary outcomes are the onset of substance use disorders at 4 years post-intervention (year 5). Secondary intermediate outcomes are the onset of alcohol and substance use 2 years post-intervention and neuropsychological functions; namely, the protective effects of substance use prevention on cognitive functions generally, and executive functions and reward sensitivity specifically. This longitudinal, cluster-randomized controlled trial will investigate the impact of a brief personality-targeted intervention program on reducing the onset of addiction 4 years-post intervention. Results will tease apart the developmental sequences of uptake and growth in substance use and cognitive

  3. Retention of Statistical Concepts in a Preliminary Randomization-Based Introductory Statistics Curriculum

    Science.gov (United States)

    Tintle, Nathan; Topliff, Kylie; VanderStoep, Jill; Holmes, Vicki-Lynn; Swanson, Todd

    2012-01-01

    Previous research suggests that a randomization-based introductory statistics course may improve student learning compared to the consensus curriculum. However, it is unclear whether these gains are retained by students post-course. We compared the conceptual understanding of a cohort of students who took a randomization-based curriculum (n = 76)…

  4. [Inverse probability weighting (IPW) for evaluating and "correcting" selection bias].

    Science.gov (United States)

    Narduzzi, Silvia; Golini, Martina Nicole; Porta, Daniela; Stafoggia, Massimo; Forastiere, Francesco

    2014-01-01

    the Inverse probability weighting (IPW) is a methodology developed to account for missingness and selection bias caused by non-randomselection of observations, or non-random lack of some information in a subgroup of the population. to provide an overview of IPW methodology and an application in a cohort study of the association between exposure to traffic air pollution (nitrogen dioxide, NO₂) and 7-year children IQ. this methodology allows to correct the analysis by weighting the observations with the probability of being selected. The IPW is based on the assumption that individual information that can predict the probability of inclusion (non-missingness) are available for the entire study population, so that, after taking account of them, we can make inferences about the entire target population starting from the nonmissing observations alone.The procedure for the calculation is the following: firstly, we consider the entire population at study and calculate the probability of non-missing information using a logistic regression model, where the response is the nonmissingness and the covariates are its possible predictors.The weight of each subject is given by the inverse of the predicted probability. Then the analysis is performed only on the non-missing observations using a weighted model. IPW is a technique that allows to embed the selection process in the analysis of the estimates, but its effectiveness in "correcting" the selection bias depends on the availability of enough information, for the entire population, to predict the non-missingness probability. In the example proposed, the IPW application showed that the effect of exposure to NO2 on the area of verbal intelligence quotient of children is stronger than the effect showed from the analysis performed without regard to the selection processes.

  5. Riyadh Mother and Baby Multicenter Cohort Study: The Cohort Profile.

    Directory of Open Access Journals (Sweden)

    Hayfaa Wahabi

    Full Text Available To assess the effects of non-communicable diseases, such as diabetes, hypertension and obesity, on the mother and the infant.A multicentre cohort study was conducted in three hospitals in the city of Riyadh in Saudi Arabia. All Saudi women and their babies who delivered in participating hospitals were eligible for recruitment. Data on socio-demographic characteristics in addition to the maternal and neonatal outcomes of pregnancy were collected. The cohort demographic profile was recorded and the prevalence of maternal conditions including gestational diabetes, pre-gestational diabetes, hypertensive disorders in pregnancy and obesity were estimated.The total number of women who delivered in participating hospitals during the study period was 16,012 of which 14,568 women participated in the study. The mean age of the participants was 29 ± 5.9 years and over 40% were university graduates. Most of the participants were housewives, 70% were high or middle income and 22% were exposed to secondhand smoke. Of the total cohort, 24% were married to a first cousin. More than 68% of the participants were either overweight or obese. The preterm delivery rate was 9%, while 1.5% of the deliveries were postdate. The stillbirth rate was 13/1000 live birth. The prevalence of gestational diabetes was 24% and that of pre-gestational diabetes was 4.3%. The preeclampsia prevalence was 1.1%. The labour induction rate was 15.5% and the cesarean section rate was 25%.Pregnant women in Saudi Arabia have a unique demographic profile. The prevalence of obesity and diabetes in pregnancy are among the highest in the world.

  6. Cohort profile: the Nordic Antireflux Surgery Cohort (NordASCo).

    Science.gov (United States)

    Maret-Ouda, John; Wahlin, Karl; Artama, Miia; Brusselaers, Nele; Färkkilä, Martti; Lynge, Elsebeth; Mattsson, Fredrik; Pukkala, Eero; Romundstad, Pål; Tryggvadóttir, Laufey; Euler-Chelpin, My von; Lagergren, Jesper

    2017-06-08

    To describe a newly created all-Nordic cohort of patients with gastro-oesophageal reflux disease (GORD), entitled the Nordic Antireflux Surgery Cohort (NordASCo), which will be used to compare participants having undergone antireflux surgery with those who have not regarding risk of cancers, other diseases and mortality. Included were individuals with a GORD diagnosis recorded in any of the nationwide patient registries in the Nordic countries (Denmark, Finland, Iceland, Norway and Sweden) in 1964-2014 (with various start and end years in different countries). Data regarding cancer, other diseases and mortality were retrieved from the nationwide registries for cancer, patients and causes of death, respectively. The NordASCo includes 945 153 individuals with a diagnosis of GORD. Of these, 48 433 (5.1%) have undergone primary antireflux surgery. Median age at primary antireflux surgery ranged from 47 to 52 years in the different countries. The coding practices of GORD seem to have differed between the Nordic countries. The NordASCo will initially be used to analyse the risk of developing known or potential GORD-related cancers, that is, tumours of the oesophagus, stomach, larynx, pharynx and lung, and to evaluate the mortality in the short-term and long-term perspectives. Additionally, the cohort will be used to evaluate the risk of non-malignant respiratory conditions that might be caused by aspiration of gastric contents. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  7. The Efficacy of Single-Agent Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor Therapy in Biologically Selected Patients with Non-Small-Cell Lung Cancer: A Meta-Analysis of 19 Randomized Controlled Trials.

    Science.gov (United States)

    Li, Guifang; Gao, Shunji; Sheng, Zhixin; Li, Bin

    2016-01-01

    To determine the efficacy of first-generation single-agent epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) therapy in advanced non-small-cell lung cancer patients with known EGFR mutation status, we undertook this pooled analysis. We searched for randomized controlled trials (RCTs) in Medline, Embase, the Cochrane Controlled Trials Register, the Science Citation Index, and the American Society of Clinical Oncology annual meetings. Out of 2,129 retrieved articles, 19 RCTs enrolling 2,016 patients with wild-type EGFR tumors and 1,034 patients with mutant EGFR tumors were identified. For these EGFR mutant patients, single-agent EGFR-TKI therapy improved progression-free survival (PFS) over chemotherapy: the summary hazard ratios (HRs) were 0.41 (p well as chemotherapy in the first-line setting (HR = 1.65, p = 0.03) and in the second-/third-line setting (HR = 1.27, p = 0.006). No statistically significant difference was observed in terms of overall survival (OS). Using platinum-based doublet chemotherapy as a common comparator, indirect comparison showed the superior efficacy of single-agent EGFR-TKI therapy over EGFR-TKIs added to chemotherapy in PFS [HR = 1.35 (1.03, 1.77), p = 0.03]. Additionally, a marginal trend towards the same direction was found in the OS analysis [HR = 1.16 (0.99, 1.35), p = 0.06]. Interestingly, for those EGFR wild-type tumors, single-agent EGFR-TKI therapy was inferior to EGFR-TKIs added to chemotherapy in PFS [HR = 0.38 (0.33, 0.44), p chemotherapy. However, single-agent EGFR-TKI therapy was inferior to chemotherapy in PFS for those EGFR wild-type patients. Single-agent EGFR-TKI therapy could improve PFS over the combination of EGFR-TKIs and chemotherapy in these EGFR mutant patients. However, EGFR-TKIs combined with chemotherapy could provide additive PFS and OS benefit over single-agent EGFR-TKI therapy in those EGFR wild-type patients. © 2016 S. Karger AG, Basel.

  8. High blood pressure during pregnancy is associated with future cardiovascular disease: an observational cohort study.

    Science.gov (United States)

    Tooher, Jane; Chiu, Christine L; Yeung, Kristen; Lupton, Samantha J; Thornton, Charlene; Makris, Angela; O'Loughlin, Aiden; Hennessy, Annemarie; Lind, Joanne M

    2013-01-01

    The study aimed to determine if having a hypertensive disorder of pregnancy (HDP) is a risk factor for future cardiovascular disease (CVD), independent of age and body mass index (BMI). Data were sourced from the baseline questionnaire of the 45 and Up Study, Australia, an observational cohort study. Participants were randomly selected from the Australian Medicare Database within New South Wales. A total of 84 619 women were eligible for this study, of which 71 819 were included. These women had given birth between the ages of 18 and 45 years, had an intact uterus and ovaries, and had not been diagnosed with high blood pressure prior to their first pregnancy. HDP was associated with higher odds of having high blood pressure (high blood pressure (45.6 vs 54.8 years, phigh blood pressure, compared with women who were normotensive during pregnancy (high blood pressure (<58 years: 12.48, 10.63 to 14.66; p<0.001 and ≥58 years, 5.16, 4.54 to 5.86; p<0.001), compared with healthy weight women with a normotensive pregnancy. HDP is an independent risk factor for future CVD, and this risk is further exacerbated by the presence of overweight or obesity in later life.

  9. The impact of subacute whiplash-associated disorders on functional self-efficacy: a cohort study.

    Science.gov (United States)

    Bunketorp-Käll, Lina Sofia; Andersson, Caroline; Asker, Barbita

    2007-09-01

    Self-efficacy is increasingly being recognized as an important factor to consider in medical research, especially in different pain conditions such as whiplash-associated disorders (WAD). When pain is not effectively treated or relieved, it may negatively affect patients' life situation and cause a decline in perceived self-efficacy. Knowledge of what level of self-efficacy can be considered an actual deficit in patients with WAD is, however, sparse. The purpose of this study is to analyze whether subacute WAD has an impact on self-efficacy beliefs. A cohort study was designed to identify the impact of WAD on self-efficacy beliefs. The exposed group consisted of 47 patients with subacute WAD following a whiplash trauma. The control group representing the general population consisted of 212 participants, and was randomly selected to match the distribution of age and sex in the exposed group. The Self-Efficacy Scale was used to assess the individuals' confidence in their ability to successfully carry out activities of daily living. In the exposed group, 47 responded (100%), and in the control group, 113 (53%) responded. The results show that the total scores on the Self-Efficacy Scale were significantly lower in the exposed group compared with the control group, concerning both the mean (P<0.001) and median (P<0.001) scores. In conclusion, patients with subacute WAD experience a decline in functional self-efficacy, which stresses the importance of incorporating these beliefs in clinical practice and research.

  10. Beyond Meatless, the Health Effects of Vegan Diets: Findings from the Adventist Cohorts

    Directory of Open Access Journals (Sweden)

    Lap Tai Le

    2014-05-01

    Full Text Available Vegetarians, those who avoid meat, and vegans, additionally avoiding dairy and eggs, represent 5% and 2%, respectively, of the US population. The aim of this review is to assess the effects of vegetarian diets, particularly strict vegetarian diets (i.e., vegans on health and disease outcomes. We summarized available evidence from three prospective cohorts of Adventists in North America: Adventist Mortality Study, Adventist Health Study, and Adventist Health Study-2. Non-vegetarian diets were compared to vegetarian dietary patterns (i.e., vegan and lacto-ovo-vegetarian on selected health outcomes. Vegetarian diets confer protection against cardiovascular diseases, cardiometabolic risk factors, some cancers and total mortality. Compared to lacto-ovo-vegetarian diets, vegan diets seem to offer additional protection for obesity, hypertension, type-2 diabetes, and cardiovascular mortality. Males experience greater health benefits than females. Limited prospective data is available on vegetarian diets and body weight change. Large randomized intervention trials on the effects of vegetarian diet patterns on neurological and cognitive functions, obesity, diabetes, and other cardiovascular outcomes are warranted to make meaningful recommendations.

  11. Beyond meatless, the health effects of vegan diets: findings from the Adventist cohorts.

    Science.gov (United States)

    Le, Lap Tai; Sabaté, Joan

    2014-05-27

    Vegetarians, those who avoid meat, and vegans, additionally avoiding dairy and eggs, represent 5% and 2%, respectively, of the US population. The aim of this review is to assess the effects of vegetarian diets, particularly strict vegetarian diets (i.e., vegans) on health and disease outcomes. We summarized available evidence from three prospective cohorts of Adventists in North America: Adventist Mortality Study, Adventist Health Study, and Adventist Health Study-2. Non-vegetarian diets were compared to vegetarian dietary patterns (i.e., vegan and lacto-ovo-vegetarian) on selected health outcomes. Vegetarian diets confer protection against cardiovascular diseases, cardiometabolic risk factors, some cancers and total mortality. Compared to lacto-ovo-vegetarian diets, vegan diets seem to offer additional protection for obesity, hypertension, type-2 diabetes, and cardiovascular mortality. Males experience greater health benefits than females. Limited prospective data is available on vegetarian diets and body weight change. Large randomized intervention trials on the effects of vegetarian diet patterns on neurological and cognitive functions, obesity, diabetes, and other cardiovascular outcomes are warranted to make meaningful recommendations.

  12. Plasma sterols and depressive symptom severity in a population-based cohort.

    Directory of Open Access Journals (Sweden)

    Basar Cenik

    Full Text Available Convergent evidence strongly suggests major depressive disorder is heterogeneous in its etiology and clinical characteristics. Depression biomarkers hold potential for identifying etiological subtypes, improving diagnostic accuracy, predicting treatment response, and personalization of treatment. Human plasma contains numerous sterols that have not been systematically studied. Changes in cholesterol concentrations have been implicated in suicide and depression, suggesting plasma sterols may be depression biomarkers. Here, we investigated associations between plasma levels of 34 sterols (measured by mass spectrometry and scores on the Quick Inventory of Depressive Symptomatology-Self Report (QIDS-SR16 scale in 3117 adult participants in the Dallas Heart Study, an ethnically diverse, population-based cohort. We built a random forest model using feature selection from a pool of 43 variables including demographics, general health indicators, and sterol concentrations. This model comprised 19 variables, 13 of which were sterol concentrations, and explained 15.5% of the variation in depressive symptoms. Desmosterol concentrations below the fifth percentile (1.9 ng/mL, OR 1.9, 95% CI 1.2-2.9 were significantly associated with depressive symptoms of at least moderate severity (QIDS-SR16 score ≥10.5. This is the first study reporting a novel association between plasma concentrations cholesterol precursors and depressive symptom severity.

  13. Dialysis Modality and Readmission Following Hospital Discharge: A Population-Based Cohort Study.

    Science.gov (United States)

    Perl, Jeffrey; McArthur, Eric; Bell, Chaim; Garg, Amit X; Bargman, Joanne M; Chan, Christopher T; Harel, Shai; Li, Lihua; Jain, Arsh K; Nash, Danielle M; Harel, Ziv

    2017-07-01

    Readmissions following hospital discharge among maintenance dialysis patients are common, potentially modifiable, and costly. Compared with patients receiving in-center hemodialysis (HD), patients receiving peritoneal dialysis (PD) have fewer routine dialysis clinic encounters and as a result may be more susceptible to a hospital readmission following discharge. Population-based retrospective-cohort observational study. Patients treated with maintenance dialysis who were discharged following an acute-care hospitalization during January 1, 2003, to December 31, 2013, across 164 acute-care hospitals in Ontario, Canada. For those with multiple hospitalizations, we randomly selected a single hospitalization as the index hospitalization. Dialysis modality PD or in-center HD. Propensity scores were used to match each patient on PD therapy to 2 patients on in-center HD therapy to ensure that baseline indicators of health were similar between the 2 groups. All-cause 30-day readmission following the index hospital discharge. 28,026 dialysis patients were included in the study. 4,013 PD patients were matched to 8,026 in-center HD patients. Among the matched cohort, 30-day readmission rates were 7.1 (95% CI, 6.6-7.6) per 1,000 person-days for patients on PD therapy and 6.0 (95% CI, 5.7-6.3) per 1,000 person-days for patients on in-center HD therapy. The risk for a 30-day readmission among patients on PD therapy was higher compared with those on in-center HD therapy (adjusted HR, 1.19; 95% CI, 1.08-1.31). The primary results were consistent across several key prespecified subgroups. Lack of information for the frequency of nephrology physician encounters following discharge from the hospital in both the PD and in-center HD cohorts. Limited validation of International Classification of Diseases, Tenth Revision codes. The risk for 30-day readmission is higher for patients on home-based PD compared to in-center HD therapy. Interventions to improve transitions in care between the

  14. Randomizer for High Data Rates

    Science.gov (United States)

    Garon, Howard; Sank, Victor J.

    2018-01-01

    NASA as well as a number of other space agencies now recognize that the current recommended CCSDS randomizer used for telemetry (TM) is too short. When multiple applications of the PN8 Maximal Length Sequence (MLS) are required in order to fully cover a channel access data unit (CADU), spectral problems in the form of elevated spurious discretes (spurs) appear. Originally the randomizer was called a bit transition generator (BTG) precisely because it was thought that its primary value was to insure sufficient bit transitions to allow the bit/symbol synchronizer to lock and remain locked. We, NASA, have shown that the old BTG concept is a limited view of the real value of the randomizer sequence and that the randomizer also aids in signal acquisition as well as minimizing the potential for false decoder lock. Under the guidelines we considered here there are multiple maximal length sequences under GF(2) which appear attractive in this application. Although there may be mitigating reasons why another MLS sequence could be selected, one sequence in particular possesses a combination of desired properties which offsets it from the others.

  15. A retrospective cohort study on the association between periapical abscess, advanced periodontal disease, and the national oral health screening program among Korean adults.

    Science.gov (United States)

    Ha, Jung-Eun; Jung, Se-Hwan; Jin, Bo-Hyoung; Lee, Byoung-Jin; Bae, Kwang-Hak

    2013-09-01

    The National Oral Health Screening Program (NOHSP) is a general population-based program in Korea. The objective of this study was to assess the association between participation in the NOHSP and dental visit for periapical abscess (PA) and advanced periodontal disease (APD) among Korean adults. Data were obtained for subjects from the National Health Insurance database. The authors conducted a retrospective cohort study of 9358 randomly selected subjects who were between 40 and 64 years old in 2002. The outcomes of dental visit for PA or APD from the years 2003 to 2007 were compared between the screening and nonscreening groups. The nonscreening group had 19% higher risk of PA and 15% higher risk of APD. This study suggests that the NOHSP may decrease the risk of dental visit because of PA and APD by preventing the progress of lesion to the advanced stage among Korean adults.

  16. Interaction between interleukin-10 (IL-10) polymorphisms and dietary fibre in relation to risk of colorectal cancer in a Danish case-cohort study

    DEFF Research Database (Denmark)

    Andersen, Vibeke; Egeberg, Rikke; Tjonneland, Anne

    2012-01-01

    -inflammatory cytokine. We wanted to test if dietary factors and IL10 polymorphisms interact in relation to colorectal carcinogenesis. Methods: The functional IL10 polymorphism C-592A (rs1800872) and the marker rs3024505 were assessed in relation to diet and lifestyle in a nested case-cohort study of 378 CRC cases...... and 775 randomly selected participants from a prospective study of 57,053 persons. Genotyping data on the IL10 polymorphism C-592A, smoking and nonsteroidal anti-inflammatory drugs (NSAID) was retrieved from Vogel et al. (Mutat Res, 2007; 624: 88). Incidence rate ratios (IRR) and 95% Confidence Interval...... (95% CI) were calculated. Results: No associations were found between the IL10 rs3024505 polymorphism and risk of CRC. There was interaction between rs3024505 and dietary fibre (P-value for interaction = 0.01). IL10 rs3024505 homozygous wildtype carriers were at 27% reduced risk of CRC per 10 g fibre...

  17. Cohort profile: The Limache, Chile, birth cohort study.

    Science.gov (United States)

    Amigo, Hugo; Bustos, Patricia; Zumelzú, Elinor; Rona, Roberto J

    2014-08-01

    The Limache cohort was set up to assess the programming and life course events hypotheses in relation to cardiovascular risk factors and chronic respiratory conditions, especially asthma, in the context of an unprecedented economic growth in Chile. The cohort was a representative sample of 1232 participants born between 1974 and 1978 in the hospital of Limache. The study includes data collected at birth, during the 1st year of life, at 22 to 28 years (collected between 2000 and 2002) and at 32 to 38 years (collected between 2010 and 2012). The data collected include anthropometric measurements at birth, 1st year of life and in adulthood, socio-economic and demographic data, lifestyle information including smoking, alcohol consumption and food intake, respiratory symptoms, lung function, broncho-reactivity to methacholine and skin prick reaction to eight allergens, measurement of cardiovascular risk factors and information on common mental health, mainly in the most recent study. The principal researchers welcome collaborative projects, especially those that will compare similar data sets in other settings. Published by Oxford University Press on behalf of the International Epidemiological Association © The Author 2013; all rights reserved.

  18. Effects of trans fatty acids on glucose homeostasis: a meta-analysis of randomized, placebo-controlled clinical trials123

    OpenAIRE

    Aronis, Konstantinos N; Khan, Sami M; Mantzoros, Christos S

    2012-01-01

    Background: Although evidence from cohort studies has suggested that trans fatty acid (TFA) consumption may be associated with insulin resistance and diabetes, randomized placebo-controlled trials (RCTs) have yielded conflicting results.

  19. The Danish National Birth Cohort

    DEFF Research Database (Denmark)

    Olsen, J; Melbye, M; Olsen, S F

    2001-01-01

    component causes that act early in life. Exposures in this period, which influence fetal growth, cell divisions, and organ functioning, may have long-lasting impact on health and disease susceptibility. METHODS: To investigate these issues the Danish National Birth Cohort (Better health for mother and child...... bank has been set up with blood taken from the mother twice during pregnancy and blood from the umbilical cord taken shortly after birth. Data collection started in 1996 and the project covered all regions in Denmark in 1999. By August 2000. a total of 60,000 pregnant women had been recruited...

  20. Quantification of the heterogeneity of prognostic cellular biomarkers in ewing sarcoma using automated image and random survival forest analysis.

    Directory of Open Access Journals (Sweden)

    Claudia Bühnemann

    Full Text Available Driven by genomic somatic variation, tumour tissues are typically heterogeneous, yet unbiased quantitative methods are rarely used to analyse heterogeneity at the protein level. Motivated by this problem, we developed automated image segmentation of images of multiple biomarkers in Ewing sarcoma to generate distributions of biomarkers between and within tumour cells. We further integrate high dimensional data with patient clinical outcomes utilising random survival forest (RSF machine learning. Using material from cohorts of genetically diagnosed Ewing sarcoma with EWSR1 chromosomal translocations, confocal images of tissue microarrays were segmented with level sets and watershed algorithms. Each cell nucleus and cytoplasm were identified in relation to DAPI and CD99, respectively, and protein biomarkers (e.g. Ki67, pS6, Foxo3a, EGR1, MAPK localised relative to nuclear and cytoplasmic regions of each cell in order to generate image feature distributions. The image distribution features were analysed with RSF in relation to known overall patient survival from three separate cohorts (185 informative cases. Variation in pre-analytical processing resulted in elimination of a high number of non-informative images that had poor DAPI localisation or biomarker preservation (67 cases, 36%. The distribution of image features for biomarkers in the remaining high quality material (118 cases, 104 features per case were analysed by RSF with feature selection, and performance assessed using internal cross-validation, rather than a separate validation cohort. A prognostic classifier for Ewing sarcoma with low cross-validation error rates (0.36 was comprised of multiple features, including the Ki67 proliferative marker and a sub-population of cells with low cytoplasmic/nuclear ratio of CD99. Through elimination of bias, the evaluation of high-dimensionality biomarker distribution within cell populations of a tumour using random forest analysis in quality

  1. Quantification of the heterogeneity of prognostic cellular biomarkers in ewing sarcoma using automated image and random survival forest analysis.

    Science.gov (United States)

    Bühnemann, Claudia; Li, Simon; Yu, Haiyue; Branford White, Harriet; Schäfer, Karl L; Llombart-Bosch, Antonio; Machado, Isidro; Picci, Piero; Hogendoorn, Pancras C W; Athanasou, Nicholas A; Noble, J Alison; Hassan, A Bassim

    2014-01-01

    Driven by genomic somatic variation, tumour tissues are typically heterogeneous, yet unbiased quantitative methods are rarely used to analyse heterogeneity at the protein level. Motivated by this problem, we developed automated image segmentation of images of multiple biomarkers in Ewing sarcoma to generate distributions of biomarkers between and within tumour cells. We further integrate high dimensional data with patient clinical outcomes utilising random survival forest (RSF) machine learning. Using material from cohorts of genetically diagnosed Ewing sarcoma with EWSR1 chromosomal translocations, confocal images of tissue microarrays were segmented with level sets and watershed algorithms. Each cell nucleus and cytoplasm were identified in relation to DAPI and CD99, respectively, and protein biomarkers (e.g. Ki67, pS6, Foxo3a, EGR1, MAPK) localised relative to nuclear and cytoplasmic regions of each cell in order to generate image feature distributions. The image distribution features were analysed with RSF in relation to known overall patient survival from three separate cohorts (185 informative cases). Variation in pre-analytical processing resulted in elimination of a high number of non-informative images that had poor DAPI localisation or biomarker preservation (67 cases, 36%). The distribution of image features for biomarkers in the remaining high quality material (118 cases, 104 features per case) were analysed by RSF with feature selection, and performance assessed using internal cross-validation, rather than a separate validation cohort. A prognostic classifier for Ewing sarcoma with low cross-validation error rates (0.36) was comprised of multiple features, including the Ki67 proliferative marker and a sub-population of cells with low cytoplasmic/nuclear ratio of CD99. Through elimination of bias, the evaluation of high-dimensionality biomarker distribution within cell populations of a tumour using random forest analysis in quality controlled tumour

  2. RESEARCH ARTICLE Analysis of polymorphisms and selective ...

    Indian Academy of Sciences (India)

    2017-01-27

    Jan 27, 2017 ... The presence of purifying selection and low nucleotide diversity indicated that ... protein in Plasmodium spp., and they are mainly due to single nucleotide polymorphisms (SNPs) ... This study was approved by Medical Research & Ethics Committee of the Ministry of. Health ..... X. Asembo Bay Cohort Project.

  3. Attention deficit/hyperactivity disorder and childhood autism in association with prenatal exposure to perfluoroalkyl substances: a nested case-control study in the Danish National Birth Cohort.

    Science.gov (United States)

    Liew, Zeyan; Ritz, Beate; von Ehrenstein, Ondine S; Bech, Bodil Hammer; Nohr, Ellen Aagaard; Fei, Chunyuan; Bossi, Rossana; Henriksen, Tine Brink; Bonefeld-Jørgensen, Eva Cecilie; Olsen, Jørn

    2015-04-01

    Perfluoroalkyl substances (PFASs) are persistent pollutants found to be endocrine disruptive and neurotoxic in animals. Positive correlations between PFASs and neurobehavioral problems in children were reported in cross-sectional data, but findings from prospective studies are limited. We investigated whether prenatal exposure to PFASs is associated with attention deficit/hyperactivity disorder (ADHD) or childhood autism in children. Among 83,389 mother-child pairs enrolled in the Danish National Birth Cohort during 1996-2002, we identified 890 ADHD cases and 301 childhood autism cases from the Danish National Hospital Registry and the Danish Psychiatric Central Registry. From this cohort, we randomly selected 220 cases each of ADHD and autism, and we also randomly selected 550 controls frequency matched by child's sex. Sixteen PFASs were measured in maternal plasma collected in early or mid-pregnancy. We calculated risk ratios (RRs) using generalized linear models, taking into account sampling weights. Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) were detected in all samples; four other PFASs were quantified in ≥ 90% of the samples. We did not find consistent evidence of associations between mother's PFAS plasma levels and ADHD [per natural log nanograms per milliliter increase: PFOS RR = 0.87 (95% CI: 0.74, 1.02); PFOA RR = 0.98 (95% CI: 0.82, 1.16)] or autism [per natural log nanograms per milliliter increase: PFOS RR = 0.92 (95% CI: 0.69, 1.22); PFOA RR = 0.98 (95% CI: 0.73, 1.31)]. We found positive as well as negative associations between higher PFAS quartiles and ADHD in models that simultaneously adjusted for all PFASs, but these estimates were imprecise. In this study we found no consistent evidence to suggest that prenatal PFAS exposure increases the risk of ADHD or childhood autism in children.

  4. Understanding trends in Australian alcohol consumption-an age-period-cohort model.

    Science.gov (United States)

    Livingston, Michael; Raninen, Jonas; Slade, Tim; Swift, Wendy; Lloyd, Belinda; Dietze, Paul

    2016-09-01

    To decompose Australian trends in alcohol consumption into their age, period (survey year) and cohort (birth year/generation) components. In particular, we aimed to test whether recent declines in overall consumption have been influenced by reductions in drinking among recently born cohorts. Seven cross-sectional waves of the Australian National Drug Strategy Household Survey (1995-2013). Age, period and cohort effects were estimated using a linear and logistic cross-classified random-effects models (CCREMs). Australia A total of 124 440 Australians (69 193 females and 55 257 males), aged 14-79 years. Whether or not respondents consumed alcohol in the 12 months prior to the survey and, for those who did, the estimated volume of pure alcohol consumed, derived using standard quantity-frequency survey questions. Controlling for age and period effects, there was significant variation in drinking participation and drinking volume by birth cohort. In particular, male cohorts born between the 1965 and 1974 and female cohorts born between 1955 and 1974 reported higher rates of drinking participation (P women (P < 0.01). Recent birth cohorts (born between 1995 and 1999) in Australia report significantly lower rates of both drinking participation and drinking volume than previous cohorts, controlling for their age distribution and overall changes in population drinking. These findings suggest that the recent decline in alcohol consumption in Australia has been driven by declines in drinking among these recently born cohorts. These trends are consistent with international shifts in youth drinking. © 2016 Society for the Study of Addiction.

  5. The Netherlands Cohort Study – Meat Investigation Cohort; a population-based cohort over-represented with vegetarians, pescetarians and low meat consumers

    Science.gov (United States)

    2013-01-01

    Background Vegetarian diets have been associated with lower risk of chronic disease, but little is known about the health effects of low meat diets and the reliability of self-reported vegetarian status. We aimed to establish an analytical cohort over-represented with vegetarians, pescetarians and 1 day/week meat consumers, and to describe their lifestyle and dietary characteristics. In addition, we were able to compare self-reported vegetarians with vegetarians whose status has been confirmed by their response on the extensive food frequency questionnaire (FFQ). Study methods Embedded within the Netherlands Cohort Study (n = 120,852; including 1150 self-reported vegetarians), the NLCS-Meat Investigation Cohort (NLCS-MIC) was defined by combining all FFQ-confirmed-vegetarians (n = 702), pescetarians (n = 394), and 1 day/week meat consumers (n = 1,396) from the total cohort with a random sample of 2–5 days/week- and 6–7 days/week meat consumers (n = 2,965 and 5,648, respectively). Results Vegetarians, pescetarians, and 1 day/week meat consumers had more favorable dietary intakes (e.g. higher fiber/vegetables) and lifestyle characteristics (e.g. lower smoking rates) compared to regular meat consumers in both sexes. Vegetarians adhered to their diet longer than pescetarians and 1 day/week meat consumers. 75% of vegetarians with a prevalent cancer at baseline had changed to this diet after diagnosis. 50% of self-reported vegetarians reported meat or fish consumption on the FFQ. Although the misclassification that occurred in terms of diet and lifestyle when merely relying on self-reporting was relatively small, the impact on associations with disease risk remains to be studied. Conclusion We established an analytical cohort over-represented with persons at the lower end of the meat consumption spectrum which should facilitate prospective studies of major cancers and causes of death using ≥20.3 years of follow-up. PMID:24289207

  6. On a randomly imperfect spherical cap pressurized by a random ...

    African Journals Online (AJOL)

    On a randomly imperfect spherical cap pressurized by a random dynamic load. ... In this paper, we investigate a dynamical system in a random setting of dual ... characterization of the random process for determining the dynamic buckling load ...

  7. Primary ICD-therapy in patients with advanced heart failure: selection strategies and future trials.

    Science.gov (United States)

    Frankenstein, Lutz; Zugck, Christian; Nelles, Manfred; Schellberg, Dieter; Remppis, Andrew; Katus, Hugo

    2008-09-01

    For allocation of primary ICD-therapy, a possible lower limit of inclusion criteria--defining overly advanced heart failure--is less well investigated. Also, a multi-variable approach to stratification beyond ejection fraction (LVEF) appears warranted. We examined whether adding a selection limit of peak VO(2) cohort. In our prospective clinical registry 1,926 patients with systolic CHF were recruited consecutively since 1994. Of these patients, 292 met the selection criteria described above. The mean age was 57.6 +/- 9.5 years, 83% were male, 37% had ischemic cardiomyopathy and 28% received primary ICD-therapy. All cause mortality was considered as end point. Median follow-up was 45 (18-86) months. ICD was not a significant predictor of outcome either for the entire population, or grouped according to aetiology of CHF. Still, 3-year mortality was 15% (ICD-patients) Vs. 28% (non-ICD-patients); P = 0.05; under combination medical therapy. Inversely, in ICD-patients medical combination therapy conveyed a significant survival benefit (P < 0.001). Consequently, the number-needed-to-treat was eight under combination therapy and the size estimate amounts to 300 patients for a prospective trial in this cohort. A cut-off of LVEF randomized trial in this cohort. The according mortality data and a size estimate are provided.

  8. Random walks, random fields, and disordered systems

    CERN Document Server

    Černý, Jiří; Kotecký, Roman

    2015-01-01

    Focusing on the mathematics that lies at the intersection of probability theory, statistical physics, combinatorics and computer science, this volume collects together lecture notes on recent developments in the area. The common ground of these subjects is perhaps best described by the three terms in the title: Random Walks, Random Fields and Disordered Systems. The specific topics covered include a study of Branching Brownian Motion from the perspective of disordered (spin-glass) systems, a detailed analysis of weakly self-avoiding random walks in four spatial dimensions via methods of field theory and the renormalization group, a study of phase transitions in disordered discrete structures using a rigorous version of the cavity method, a survey of recent work on interacting polymers in the ballisticity regime and, finally, a treatise on two-dimensional loop-soup models and their connection to conformally invariant systems and the Gaussian Free Field. The notes are aimed at early graduate students with a mod...

  9. Relationship of zolpidem and cancer risk: a Taiwanese population-based cohort study.

    Science.gov (United States)

    Kao, Chia-Hung; Sun, Li-Min; Liang, Ji-An; Chang, Shih-Ni; Sung, Fung-Chang; Muo, Chih-Hsin

    2012-05-01

    To evaluate the relationship between the use of zolpidem and subsequent cancer risk in Taiwanese patients. We used data from the National Health Insurance system of Taiwan to investigate whether use of zolpidem was related to cancer risk. For the study cohort, we identified 14,950 patients who had received a first prescription for zolpidem from January 1, 1998, through December 31, 2000. For each zolpidem user, we selected randomly 4 comparison patients without a history of using zolpidem who were frequency-matched by sex, age, and year of the index date. Incidence rates of all cancers and selected site-specific cancers were measured by the end of 2009, and related hazard ratios (HRs) and 95% confidence intervals (CIs) of the cancer were measured as well. The risk of developing any cancer was greater in patients using zolpidem than in nonusers (HR, 1.68; 95% CI, 1.55-1.82). The stratified analysis showed that the overall HR for high-dosage zolpidem (≥300 mg/y) was 2.38. The site-specific cancer risk was the highest for oral cancer (HR, 2.36; 95% CI, 1.57-3.56), followed by kidney cancer, esophageal cancer, breast cancer, liver cancer, lung cancer, and bladder cancer (HR, 1.60; 95% CI, 1.06-2.41). Men were at higher risk than women. This population-based study revealed some unexpected findings, suggesting that the use of zolpidem may be associated with an increased risk of subsequent cancer. Further large-scale and in-depth investigations in this area are warranted. Copyright © 2012 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  10. Chocolate consumption and risk of atrial fibrillation: Two cohort studies and a meta-analysis.

    Science.gov (United States)

    Larsson, Susanna C; Drca, Nikola; Jensen-Urstad, Mats; Wolk, Alicja

    2018-01-01

    Chocolate consumption has been inconsistently associated with risk of atrial fibrillation (AF). We investigated the association between chocolate consumption and risk of AF in Swedish adults from two cohort studies and conducted a meta-analysis to summarize available evidence from cohort studies on this topic. Our study population comprised 40,009 men from the Cohort of Swedish Men and 32,486 women from the Swedish Mammography Cohort. Incident AF cases were ascertained through linkage with the Swedish National Patient Register. Published cohort studies of chocolate consumption in relation to risk of AF were identified by a PubMed search through September 14, 2017. During a mean follow-up of 14.6 years, AF was diagnosed in 9978 Swedish men and women. Compared with non-consumers, the multivariable hazard ratio of AF for those in the highest category of chocolate consumption (≥3-4 servings/week) was 0.96 (95% CI 0.88-1.04). In a random-effects meta-analysis of 5 cohort studies, including 180,454 participants and 16,356 AF cases, the hazard ratios of AF were 0.97 (95% CI 0.94-1.01) per 2 servings/week increase in chocolate consumption and 0.96 (95% CI 0.90-1.03) for the highest versus lowest category of chocolate consumption. Available data provide no evidence of an association of chocolate consumption with risk of AF. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Selective oxidation

    International Nuclear Information System (INIS)

    Cortes Henao, Luis F.; Castro F, Carlos A.

    2000-01-01

    It is presented a revision and discussion about the characteristics and factors that relate activity and selectivity in the catalytic and not catalytic partial oxidation of methane and the effect of variables as the temperature, pressure and others in the methane conversion to methanol. It thinks about the zeolites use modified for the catalytic oxidation of natural gas

  12. Selective gossip

    NARCIS (Netherlands)

    Üstebay, D.; Castro, R.M.; Rabbat, M.

    2009-01-01

    Motivated by applications in compression and distributed transform coding, we propose a new gossip algorithm called Selective Gossip to efficiently compute sparse approximations of network data. We consider running parallel gossip algorithms on the elements of a vector of transform coefficients.

  13. Misuse of randomization

    DEFF Research Database (Denmark)

    Liu, Jianping; Kjaergard, Lise Lotte; Gluud, Christian

    2002-01-01

    The quality of randomization of Chinese randomized trials on herbal medicines for hepatitis B was assessed. Search strategy and inclusion criteria were based on the published protocol. One hundred and seventy-six randomized clinical trials (RCTs) involving 20,452 patients with chronic hepatitis B...... virus (HBV) infection were identified that tested Chinese medicinal herbs. They were published in 49 Chinese journals. Only 10% (18/176) of the studies reported the method by which they randomized patients. Only two reported allocation concealment and were considered as adequate. Twenty percent (30...

  14. Lines of Descent Under Selection

    Science.gov (United States)

    Baake, Ellen; Wakolbinger, Anton

    2017-11-01

    We review recent progress on ancestral processes related to mutation-selection models, both in the deterministic and the stochastic setting. We mainly rely on two concepts, namely, the killed ancestral selection graph and the pruned lookdown ancestral selection graph. The killed ancestral selection graph gives a representation of the type of a random individual from a stationary population, based upon the individual's potential ancestry back until the mutations that define the individual's type. The pruned lookdown ancestral selection graph allows one to trace the ancestry of individuals from a stationary distribution back into the distant past, thus leading to the stationary distribution of ancestral types. We illustrate the results by applying them to a prototype model for the error threshold phenomenon.

  15. Benchmarking Variable Selection in QSAR.

    Science.gov (United States)

    Eklund, Martin; Norinder, Ulf; Boyer, Scott; Carlsson, Lars

    2012-02-01

    Variable selection is important in QSAR modeling since it can improve model performance and transparency, as well as reduce the computational cost of model fitting and predictions. Which variable selection methods that perform well in QSAR settings is largely unknown. To address this question we, in a total of 1728 benchmarking experiments, rigorously investigated how eight variable selection methods affect the predictive performance and transparency of random forest models fitted to seven QSAR datasets covering different endpoints, descriptors sets, types of response variables, and number of chemical compounds. The results show that univariate variable selection methods are suboptimal and that the number of variables in the benchmarked datasets can be reduced with about 60 % without significant loss in model performance when using multivariate adaptive regression splines MARS and forward selection. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Smooth random change point models.

    Science.gov (United States)

    van den Hout, Ardo; Muniz-Terrera, Graciela; Matthews, Fiona E

    2011-03-15

    Change point models are used to describe processes over time that show a change in direction. An example of such a process is cognitive ability, where a decline a few years before death is sometimes observed. A broken-stick model consists of two linear parts and a breakpoint where the two lines intersect. Alternatively, models can be formulated that imply a smooth change between the two linear parts. Change point models can be extended by adding random effects to account for variability between subjects. A new smooth change point model is introduced and examples are presented that show how change point models can be estimated using functions in R for mixed-effects models. The Bayesian inference using WinBUGS is also discussed. The methods are illustrated using data from a population-based longitudinal study of ageing, the Cambridge City over 75 Cohort Study. The aim is to identify how many years before death individuals experience a change in the rate of decline of their cognitive ability. Copyright © 2010 John Wiley & Sons, Ltd.

  17. Association between diverticular disease and Ehlers-Danlos syndrome: a 13-year nationwide population-based cohort study.

    Science.gov (United States)

    Leganger, Julie; Søborg, Marie-Louise Kulas; Mortensen, Laura Quitzau; Gregersen, Rasmus; Rosenberg, Jacob; Burcharth, Jakob

    2016-12-01

    The aim of this study was to examine occurrence and consequences of diverticular disease in patients with Ehlers-Danlos syndrome (EDS) compared with a matched cohort. This nationwide population-based cohort study was conducted using data from medical registers in Denmark from year 2000 to 2012. The EDS cohort was identified using the specific diagnosis code for EDS and was randomly matched in a ratio of 1:20 by sex and date of birth (±1 year) with persons from the Danish general population. The occurrence of diverticular disease and the clinical characteristics of the initial diverticular event were compared between the EDS cohort and the comparison cohort. The first admission with diverticulitis was identified, and severity of diverticulitis, treatment, colonoscopies, length of stay, and 30-day mortality were investigated. We identified 1336 patients with EDS and matched a control cohort of 26,720 patients. The occurrence of diverticular disease in the EDS cohort (2.0 %) and the comparison cohort (0.68 %) differed significantly (p < 0.001). At the first diverticular event, the majority of patients were women (85 % for EDS and 87 % for the comparison cohort). Mean age, localization, and type of contact did not differ significantly. Admission with diverticulitis (1.0 % for EDS and 0.34 % for the comparison cohort) differed significantly (p < 0.001). We found no significant difference in severity of diverticulitis, treatment, length of stay, or 30-day mortality between the EDS and the comparison cohorts. Patients with EDS had an increased occurrence of overall diverticular events and admissions with diverticulitis compared with the general population.

  18. Generating equilateral random polygons in confinement III

    International Nuclear Information System (INIS)

    Diao, Y; Ernst, C; Montemayor, A; Ziegler, U

    2012-01-01

    In this paper we continue our earlier studies (Diao et al 2011 J. Phys. A: Math. Theor. 44 405202, Diao et al J. Phys. A: Math. Theor. 45 275203) on the generation methods of random equilateral polygons confined in a sphere. The first half of this paper is concerned with the generation of confined equilateral random walks. We show that if the selection of a vertex is uniform subject to the position of its previous vertex and the confining condition, then the distributions of the vertices are not uniform, although there exists a distribution such that if the initial vertex is selected following this distribution, then all vertices of the random walk follow this same distribution. Thus in order to generate a confined equilateral random walk, the selection of a vertex cannot be uniform subject to the position of its previous vertex and the confining condition. We provide a simple algorithm capable of generating confined equilateral random walks whose vertex distribution is almost uniform in the confinement sphere. In the second half of this paper we show that any process generating confined equilateral random walks can be turned into a process generating confined equilateral random polygons with the property that the vertex distribution of the polygons approaches the vertex distribution of the walks as the polygons get longer and longer. In our earlier studies, the starting point of the confined polygon is fixed at the center of the sphere. The new approach here allows us to move the starting point of the confined polygon off the center of the sphere. (paper)

  19. Pregnancy and birth cohort resources in Europe

    DEFF Research Database (Denmark)

    Larsen, Pernille Stemann; Kamper-Jørgensen, Mads; Adamson, Ashley

    2013-01-01

    During the past 25 years, many pregnancy and birth cohorts have been established. Each cohort provides unique opportunities for examining associations of early-life exposures with child development and health. However, to fully exploit the large amount of available resources and to facilitate cross...

  20. A Chinese Birth Cohort: Theoretical Implications

    Science.gov (United States)

    Friday, Paul C.; Ren, Xin; Weitekamp, Elmar; Kerner, Hans-Jurgen; Taylor, Terrance

    2005-01-01

    Research on delinquency has shown consistent results across Western industrialized countries. Few studies have been done in non-Western cultures. This study reports on the results of a birth cohort study in China, which was started by Marvin Wolfgang but never completed. The cohort, born in 1973, was traced through official and community files.…

  1. Pooling birth cohorts in allergy and asthma

    DEFF Research Database (Denmark)

    Bousquet, Jean; Anto, Josep; Sunyer, Jordi

    2013-01-01

    Long-term birth cohort studies are essential to understanding the life course and childhood predictors of allergy and the complex interplay between genes and the environment (including lifestyle and socioeconomic determinants). Over 100 cohorts focusing on asthma and allergy have been initiated...

  2. Delay to mental healthcare in a cohort of Canadian Armed Forces personnel with deployment-related mental disorders, 2002–2011: a retrospective cohort study

    Science.gov (United States)

    Boulos, David; Zamorski, Mark A

    2016-01-01

    Objective To assess whether the delay to care among Canadian Armed Forces (CAF) personnel who sought care for a mental disorder changed over time and in association with CAF mental health system augmentations. Design A stratified, random sample (n=2014) was selected for study from an Afghanistan-deployed cohort (N=30 513) and the 415 (weighted N=4108) individuals diagnosed with an Afghanistan service-related mental disorder were further assessed. Diagnosis-related data were abstracted from medical records (22 June 2010 to 30 May 2011). Other data were extracted from administrative databases. Delay to care was assessed across five mental health system eras: 2002/2004, 2005/2006, 2007, 2008 and 2009/2010. Weighted Cox proportional hazards regression assessed the association between era, handled as a time-dependent covariate, and the outcome while controlling for a broad range of potential confounders (ie, sociodemographic, military and clinical characteristics). Taylor series linearisation methods and sample design weights were applied in generating descriptive and regression analysis statistics. Primary outcome The outcome was the delay to mental healthcare, defined as the latency from most recent Afghanistan deployment return date to diagnosis date, among individuals with an Afghanistan service-related mental disorder diagnosis. Results Mean delay to care was 551 days (95% CI 501 to 602); the median was 400 days. Delay to care decreased in subsequent eras relative to 2002/2004; however, only the most recent era (2009/2010) was statistically significant (adjusted HR (aHR): 3.01 (95% CI 1.91 to 4.73)). Men, operations support occupations, higher ranks, non-musculoskeletal comorbidities and fewer years of military service were also independently associated with longer delays to care. Conclusions CAF mental health system changes were associated with reduced delays to mental healthcare. Further evaluation research is needed to identify the key system changes that

  3. [The PreFord Study. A prospective cohort study to evaluate the risk of a cardiovascular event (overall-collective) as well as a prospective, randomized, controlled, multicentre clinical intervention study (high-risk-collective) on primary prevention of cardiovascular diseases in the Ford Motor Company employees in Germany].

    Science.gov (United States)

    Gysan, D B; Latsch, J; Bjarnason-Wehrens, B; Albus, C; Falkowski, G; Herold, G; Mey, E; Heinzler, R; Montiel, G; Schneider, C A; Stützer, H; Türk, S; Weisbrod, M; Predel, H G

    2004-02-01

    The PreFord Study is a multicenter prospective cohort study to evaluate guideline based risk management on primary prevention of cardiovascular diseases. Furthermore a randomised controlled trial (RCT) will be designed to analyse the effect of a special intervention program. 40,000 employees of the Ford Motor Company, Visteon Company and Deutz Company in Germany will be included, monitored for ten years and the following primary endpoints will be investigated: 1. evaluation and comparison of established and newly developed risk-scores, 2. the relative impact of single and combined cardiovascular risk factors on cardiovascular diseases, 3. the influence of a novel occupationally integrated ambulant rehabilitation program in combination with a guideline oriented optimal drug therapy within a high risk group on the primary endpoint: risk reduction by, 4. the influence of this intervention on secondary endpoints: death, myocardial infarction and stroke, combined appearance of angina pectoris and hospitalisation, occurrence of cerebral circulatory disorder and hospitalisation, occurrence of peripheral occlusive arterial disease and hospitalisation and single cardiovascular risk factors and cost-benefit-analysis. Beginning with an cross sectional study there will be a systemic screening of cardiovascular risk profiles, of anthropometric data and different lifestyle-factors. Based on these data participants will be differentiated into three risk-groups according to the risk score of the European Society of Cardiology (risk of a lethal primary acute cardiovascular event: I 1- or = 5%). In the following longitudinal study different strategies will be applied: Group I: low risk ( 1.5% per year or >15% within the next 10 years) will be randomised into two interventional groups. The first one, the intervention-group "PreFord" will perform an occupational integrated rehabilitation program (2,5-3 hours twice a week, for 15 weeks according to the BAR guidelines) with a following

  4. Ricardian selection

    OpenAIRE

    Finicelli, Andrea; Pagano, Patrizio; Sbracia, Massimo

    2009-01-01

    We analyze the foundations of the relationship between trade and total factor productivity (TFP) in the Ricardian model. Under general assumptions about the autarky distributions of industry productivities, trade openness raises TFP. This is due to the selection effect of international competition � driven by comparative advantages � which makes "some" high- and "many" low-productivity industries exit the market. We derive a model-based measure of this effect that requires only production...

  5. Randomized Prediction Games for Adversarial Machine Learning.

    Science.gov (United States)

    Rota Bulo, Samuel; Biggio, Battista; Pillai, Ignazio; Pelillo, Marcello; Roli, Fabio

    In spam and malware detection, attackers exploit randomization to obfuscate malicious data and increase their chances of evading detection at test time, e.g., malware code is typically obfuscated using random strings or byte sequences to hide known exploits. Interestingly, randomization has also been proposed to improve security of learning algorithms against evasion attacks, as it results in hiding information about the classifier to the attacker. Recent work has proposed game-theoretical formulations to learn secure classifiers, by simulating different evasion attacks and modifying the classification function accordingly. However, both the classification function and the simulated data manipulations have been modeled in a deterministic manner, without accounting for any form of randomization. In this paper, we overcome this limitation by proposing a randomized prediction game, namely, a noncooperative game-theoretic formulation in which the classifier and the attacker make randomized strategy selections according to some probability distribution defined over the respective strategy set. We show that our approach allows one to improve the tradeoff between attack detection and false alarms with respect to the state-of-the-art secure classifiers, even against attacks that are different from those hypothesized during design, on application examples including handwritten digit recognition, spam, and malware detection.In spam and malware detection, attackers exploit randomization to obfuscate malicious data and increase their chances of evading detection at test time, e.g., malware code is typically obfuscated using random strings or byte sequences to hide known exploits. Interestingly, randomization has also been proposed to improve security of learning algorithms against evasion attacks, as it results in hiding information about the classifier to the attacker. Recent work has proposed game-theoretical formulations to learn secure classifiers, by simulating different

  6. Random surfaces and strings

    International Nuclear Information System (INIS)

    Ambjoern, J.

    1987-08-01

    The theory of strings is the theory of random surfaces. I review the present attempts to regularize the world sheet of the string by triangulation. The corresponding statistical theory of triangulated random surfaces has a surprising rich structure, but the connection to conventional string theory seems non-trivial. (orig.)

  7. Derandomizing from random strings

    NARCIS (Netherlands)

    Buhrman, H.; Fortnow, L.; Koucký, M.; Loff, B.

    2010-01-01

    In this paper we show that BPP is truth-table reducible to the set of Kolmogorov random strings R(K). It was previously known that PSPACE, and hence BPP is Turing-reducible to R(K). The earlier proof relied on the adaptivity of the Turing-reduction to find a Kolmogorov-random string of polynomial

  8. Non-cancer morbidity among Estonian Chernobyl cleanup workers: a register-based cohort study.

    Science.gov (United States)

    Rahu, Kaja; Bromet, Evelyn J; Hakulinen, Timo; Auvinen, Anssi; Uusküla, Anneli; Rahu, Mati

    2014-05-14

    To examine non-cancer morbidity in the Estonian Chernobyl cleanup workers cohort compared with the population sample with special attention to radiation-related diseases and mental health disorders. Register-based cohort study. Estonia. An exposed cohort of 3680 men (cleanup workers) and an unexposed cohort of 7631 men (population sample) were followed from 2004 to 2012 through the Population Registry and Health Insurance Fund database. Morbidity in the exposed cohort compared with the unexposed controls was estimated in terms of rate ratio (RR) with 95% CIs using Poisson regression models. Elevated morbidity in the exposed cohort was found for diseases of the nervous system, digestive system, musculoskeletal system, ischaemic heart disease and for external causes. The most salient excess risk was observed for thyroid diseases (RR=1.69; 95% CI 1.38 to 2.07), intentional self-harm (RR=1.47; 95% CI 1.04 to 2.09) and selected alcohol-related diagnoses (RR=1.25; 95% CI 1.12 to 1.39). No increase in morbidity for stress reactions, depression, headaches or sleep disorders was detected. No obvious excess morbidity consistent with biological effects of radiation was seen in the exposed cohort, with the possible exception of benign thyroid diseases. Increased alcohol-induced morbidity may reflect alcohol abuse, and could underlie some of the higher morbidity rates. Mental disorders in the exposed cohort were probably under-reported. The future challenge will be to study mental and physical comorbidities in the Chernobyl cleanup workers cohort. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  9. Correlated randomness and switching phenomena

    Science.gov (United States)

    Stanley, H. E.; Buldyrev, S. V.; Franzese, G.; Havlin, S.; Mallamace, F.; Kumar, P.; Plerou, V.; Preis, T.

    2010-08-01

    One challenge of biology, medicine, and economics is that the systems treated by these serious scientific disciplines have no perfect metronome in time and no perfect spatial architecture-crystalline or otherwise. Nonetheless, as if by magic, out of nothing but randomness one finds remarkably fine-tuned processes in time and remarkably fine-tuned structures in space. Further, many of these processes and structures have the remarkable feature of “switching” from one behavior to another as if by magic. The past century has, philosophically, been concerned with placing aside the human tendency to see the universe as a fine-tuned machine. Here we will address the challenge of uncovering how, through randomness (albeit, as we shall see, strongly correlated randomness), one can arrive at some of the many spatial and temporal patterns in biology, medicine, and economics and even begin to characterize the switching phenomena that enables a system to pass from one state to another. Inspired by principles developed by A. Nihat Berker and scores of other statistical physicists in recent years, we discuss some applications of correlated randomness to understand switching phenomena in various fields. Specifically, we present evidence from experiments and from computer simulations supporting the hypothesis that water’s anomalies are related to a switching point (which is not unlike the “tipping point” immortalized by Malcolm Gladwell), and that the bubbles in economic phenomena that occur on all scales are not “outliers” (another Gladwell immortalization). Though more speculative, we support the idea of disease as arising from some kind of yet-to-be-understood complex switching phenomenon, by discussing data on selected examples, including heart disease and Alzheimer disease.

  10. Distributional and efficiency results for subset selection

    NARCIS (Netherlands)

    Laan, van der P.

    1996-01-01

    Assume k (??k \\geq 2) populations are given. The associated independent random variables have continuous distribution functions with an unknown location parameter. The statistical selec??tion goal is to select a non??empty subset which contains the best population,?? that is the pop??ulation with

  11. Analysis of swaps in Radix selection

    DEFF Research Database (Denmark)

    Elmasry, Amr Ahmed Abd Elmoneim; Mahmoud, Hosam

    2011-01-01

    Radix Sort is a sorting algorithm based on analyzing digital data. We study the number of swaps made by Radix Select (a one-sided version of Radix Sort) to find an element with a randomly selected rank. This kind of grand average provides a smoothing over all individual distributions for specific...

  12. Selection and characterization of DNA aptamers

    NARCIS (Netherlands)

    Ruigrok, V.J.B.

    2013-01-01

    This thesis focusses on the selection and characterisation of DNA aptamers and the various aspects related to their selection from large pools of randomized oligonucleotides. Aptamers are affinity tools that can specifically recognize and bind predefined target molecules; this ability, however,

  13. Quantum random number generator

    Science.gov (United States)

    Soubusta, Jan; Haderka, Ondrej; Hendrych, Martin

    2001-03-01

    Since reflection or transmission of a quantum particle on a beamsplitter is inherently random quantum process, a device built on this principle does not suffer from drawbacks of neither pseudo-random computer generators or classical noise sources. Nevertheless, a number of physical conditions necessary for high quality random numbers generation must be satisfied. Luckily, in quantum optics realization they can be well controlled. We present an easy random number generator based on the division of weak light pulses on a beamsplitter. The randomness of the generated bit stream is supported by passing the data through series of 15 statistical test. The device generates at a rate of 109.7 kbit/s.

  14. Quantum random number generator

    Science.gov (United States)

    Pooser, Raphael C.

    2016-05-10

    A quantum random number generator (QRNG) and a photon generator for a QRNG are provided. The photon generator may be operated in a spontaneous mode below a lasing threshold to emit photons. Photons emitted from the photon generator may have at least one random characteristic, which may be monitored by the QRNG to generate a random number. In one embodiment, the photon generator may include a photon emitter and an amplifier coupled to the photon emitter. The amplifier may enable the photon generator to be used in the QRNG without introducing significant bias in the random number and may enable multiplexing of multiple random numbers. The amplifier may also desensitize the photon generator to fluctuations in power supplied thereto while operating in the spontaneous mode. In one embodiment, the photon emitter and amplifier may be a tapered diode amplifier.

  15. Autonomous Byte Stream Randomizer

    Science.gov (United States)

    Paloulian, George K.; Woo, Simon S.; Chow, Edward T.

    2013-01-01

    Net-centric networking environments are often faced with limited resources and must utilize bandwidth as efficiently as possible. In networking environments that span wide areas, the data transmission has to be efficient without any redundant or exuberant metadata. The Autonomous Byte Stream Randomizer software provides an extra level of security on top of existing data encryption methods. Randomizing the data s byte stream adds an extra layer to existing data protection methods, thus making it harder for an attacker to decrypt protected data. Based on a generated crypto-graphically secure random seed, a random sequence of numbers is used to intelligently and efficiently swap the organization of bytes in data using the unbiased and memory-efficient in-place Fisher-Yates shuffle method. Swapping bytes and reorganizing the crucial structure of the byte data renders the data file unreadable and leaves the data in a deconstructed state. This deconstruction adds an extra level of security requiring the byte stream to be reconstructed with the random seed in order to be readable. Once the data byte stream has been randomized, the software enables the data to be distributed to N nodes in an environment. Each piece of the data in randomized and distributed form is a separate entity unreadable on its own right, but when combined with all N pieces, is able to be reconstructed back to one. Reconstruction requires possession of the key used for randomizing the bytes, leading to the generation of the same cryptographically secure random sequence of numbers used to randomize the data. This software is a cornerstone capability possessing the ability to generate the same cryptographically secure sequence on different machines and time intervals, thus allowing this software to be used more heavily in net-centric environments where data transfer bandwidth is limited.

  16. The frequency of drugs in randomly selected drivers in Denmark

    DEFF Research Database (Denmark)

    Simonsen, Kirsten Wiese; Steentoft, Anni; Hels, Tove

    is the Danish legal limit. The percentage of drivers positive for medicinal drugs above the Danish legal concentration limit was 0.4%; while, 0.3% of the drivers tested positive for one or more illicit drug at concentrations exceeding the Danish legal limit. Tetrahydrocannabinol, cocaine, and amphetamine were...... the most frequent illicit drugs detected above the limit of quantitation (LOQ); while, codeine, tramadol, zopiclone, and benzodiazepines were the most frequent legal drugs. Middle aged men (median age 47.5 years) dominated the drunk driving group, while the drivers positive for illegal drugs consisted......Introduction Driving under the influence of alcohol and drugs is a global problem. In Denmark as well as in other countries there is an increasing focus on impaired driving. Little is known about the occurrence of psychoactive drugs in the general traffic. Therefore the European commission...

  17. Model Selection with the Linear Mixed Model for Longitudinal Data

    Science.gov (United States)

    Ryoo, Ji Hoon

    2011-01-01

    Model building or model selection with linear mixed models (LMMs) is complicated by the presence of both fixed effects and random effects. The fixed effects structure and random effects structure are codependent, so selection of one influences the other. Most presentations of LMM in psychology and education are based on a multilevel or…

  18. Conversion of the random amplified polymorphic DNA (RAPD ...

    African Journals Online (AJOL)

    Conversion of the random amplified polymorphic DNA (RAPD) marker UBC#116 linked to Fusarium crown and root rot resistance gene (Frl) into a co-dominant sequence characterized amplified region (SCAR) marker for marker-assisted selection of tomato.

  19. Randomized phase II study of paclitaxel/carboplatin intercalated with gefitinib compared to paclitaxel/carboplatin alone for chemotherapy-naïve non-small cell lung cancer in a clinically selected population excluding patients with non-smoking adenocarcinoma or mutated EGFR

    International Nuclear Information System (INIS)

    Choi, Yoon Ji; Lee, Dae Ho; Choi, Chang Min; Lee, Jung Shin; Lee, Seung Jin; Ahn, Jin-Hee; Kim, Sang-We

    2015-01-01

    Considering cell cycle dependent cytotoxicity, intercalation of chemotherapy and epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) may be a treatment option in non-small cell lung cancer (NSCLC). This randomized phase 2 study compared the efficacy of paclitaxel and carboplatin (PC) intercalated with gefitinib (G) versus PC alone in a selected, chemotherapy-naïve population of advanced NSCLC patients with a history of smoking or wild-type EGFR. Eligible patients were chemotherapy-naïve advanced NSCLC patients with Eastern Cooperative Oncology Group performance status of 0—2. Non-smoking patients with adenocarcinoma or patients with activating EGFR mutation were excluded because they could benefit from gefitinib alone. Eligible patients were randomized to one of the following treatment arms: PCG, P 175 mg/m 2 , and C AUC 5 administered intravenously on day 1 intercalated with G 250 mg orally on days 2 through 15 every 3 weeks for four cycles followed by G 250 mg orally until progressive disease; or PC, same dosing schedule for four cycles only. The primary endpoint was the objective response rate (ORR), and the secondary endpoints included progression-free survival (PFS), overall survival (OS), and toxicity profile. A total of 90 patients participated in the study. The ORRs were 41.9 % (95 % confidence interval (CI) 27.0–57.9 %) for the PCG arm and 39.5 % (95 % CI 25.0–55.6 %) for the PC arm (P = 0.826). No differences in PFS (4.1 vs. 4.1 months, P = 0.781) or OS (9.3 vs. 10.5 months, P = 0.827) were observed between the PCG and PC arms. Safety analyses showed a similar incidence of drug-related grade 3/4 toxicity. Rash and pruritus were more frequent in the PCG than in the PC arm. PCG did not improve ORR, PFS, and OS compared to PC chemotherapy alone for NSCLC in a clinically selected population excluding non-smoking adenocarcinoma or mutated EGFR. The study is registered with ClinicalTrials.gov (NCT01196234). Registration date is 08/09/2010

  20. Selective Europeanization

    DEFF Research Database (Denmark)

    Hoch Jovanovic, Tamara; Lynggaard, Kennet

    2014-01-01

    and rules. The article examines the reasons for both resistance and selectiveness to Europeanization of the Danish minority policy through a “path dependency” perspective accentuating decision makers’ reluctance to deviate from existing institutional commitments, even in subsequently significantly altered...... political contexts at the European level. We further show how the “translation” of international norms to a domestic context has worked to reinforce the original institutional setup, dating back to the mid-1950s. The translation of European-level minority policy developed in the 1990s and 2000s works most...

  1. Selective Reproduction

    DEFF Research Database (Denmark)

    Svendsen, Mette N.

    2015-01-01

    This article employs a multi-species perspective in investigating how life's worth is negotiated in the field of neonatology in Denmark. It does so by comparing decision-making processes about human infants in the Danish neonatal intensive care unit with those associated with piglets who serve as...... as expectations within linear or predictive time frames are key markers in both sites. Exploring selective reproductive processes across human infants and research piglets can help us uncover aspects of the cultural production of viability that we would not otherwise see or acknowledge....

  2. Cost-effectiveness of home versus clinic-based management of chronic heart failure: Extended follow-up of a pragmatic, multicentre randomized trial cohort - The WHICH? study (Which Heart Failure Intervention Is Most Cost-Effective & Consumer Friendly in Reducing Hospital Care).

    Science.gov (United States)

    Maru, Shoko; Byrnes, Joshua; Carrington, Melinda J; Chan, Yih-Kai; Thompson, David R; Stewart, Simon; Scuffham, Paul A

    2015-12-15

    To assess the long-term cost-effectiveness of two multidisciplinary management programs for elderly patients hospitalized with chronic heart failure (CHF) and how it is influenced by patient characteristics. A trial-based analysis was conducted alongside a randomized controlled trial of 280 elderly patients with CHF discharged to home from three Australian tertiary hospitals. Two interventions were compared: home-based intervention (HBI) that involved home visiting with community-based care versus specialized clinic-based intervention (CBI). Bootstrapped incremental cost-utility ratios were computed based on quality-adjusted life-years (QALYs) and total healthcare costs. Cost-effectiveness acceptability curves were constructed based on incremental net monetary benefit (NMB). We performed multiple linear regression to explore which patient characteristics may impact patient-level NMB. During median follow-up of 3.2 years, HBI was associated with slightly high