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Sample records for random sequential mechanism

  1. Catalysis of Silver catfish Major Hepatic Glutathione Transferase proceeds via rapid equilibrium sequential random Mechanism

    Directory of Open Access Journals (Sweden)

    Ayodele O. Kolawole

    2016-01-01

    Full Text Available Fish hepatic glutathione transferases are connected with the elimination of intracellular pollutants and detoxification of organic micro-pollutants in their aquatic ecosystem. The two-substrate steady state kinetic mechanism of Silver catfish (Synodontis eupterus major hepatic glutathione transferases purified to apparent homogeneity was explored. The enzyme was dimeric enzyme with a monomeric size of 25.6 kDa. Initial-velocity studies and Product inhibition patterns by methyl glutathione and chloride with respect to GSH-CDNB; GSH-ρ-nitrophenylacetate; and GSH-Ethacrynic acid all conforms to a rapid equilibrium sequential random Bi Bi kinetic mechanism rather than steady state sequential random Bi Bi kinetic. α was 2.96 ± 0.35 for the model. The pH profile of Vmax/KM (with saturating 1-chloro-2,4-dinitrobenzene and variable GSH concentrations showed apparent pKa value of 6.88 and 9.86. Inhibition studies as a function of inhibitor concentration show that the enzyme is a homodimer and near neutral GST. The enzyme poorly conjugates 4-hydroxylnonenal and cumene hydroperoxide and may not be involved in oxidative stress protection. The seGST is unique and overwhelmingly shows characteristics similar to those of homodimeric class Pi GSTs, as was indicated by its kinetic mechanism, substrate specificity and inhibition studies. The rate- limiting step, probably the product release, of the reaction is viscosity-dependent and is consequential if macro-viscosogen or micro-viscosogen.

  2. Random sequential adsorption of cubes.

    Science.gov (United States)

    Cieśla, Michał; Kubala, Piotr

    2018-01-14

    Random packings built of cubes are studied numerically using a random sequential adsorption algorithm. To compare the obtained results with previous reports, three different models of cube orientation sampling were used. Also, three different cube-cube intersection algorithms were tested to find the most efficient one. The study focuses on the mean saturated packing fraction as well as kinetics of packing growth. Microstructural properties of packings were analyzed using density autocorrelation function.

  3. Cooperation induced by random sequential exclusion

    Science.gov (United States)

    Li, Kun; Cong, Rui; Wang, Long

    2016-06-01

    Social exclusion is a common and powerful tool to penalize deviators in human societies, and thus to effectively elevate collaborative efforts. Current models on the evolution of exclusion behaviors mostly assume that each peer excluder independently makes the decision to expel the defectors, but has no idea what others in the group would do or how the actual punishment effect will be. Thus, a more realistic model, random sequential exclusion, is proposed. In this mechanism, each excluder has to pay an extra scheduling cost and then all the excluders are arranged in a random order to implement the exclusion actions. If one free rider has already been excluded by an excluder, the remaining excluders will not participate in expelling this defector. We find that this mechanism can help stabilize cooperation under more unfavorable conditions than the normal peer exclusion can do, either in well-mixed population or on social networks. However, too large a scheduling cost may undermine the advantage of this mechanism. Our work validates the fact that collaborative practice among punishers plays an important role in further boosting cooperation.

  4. A random-sequential mechanism for nitrite binding and active site reduction in copper-containing nitrite reductase

    NARCIS (Netherlands)

    Wijma, HJ; Jeuken, LJC; Verbeet, MP; Armstrong, FA; Canters, GW

    2006-01-01

    The homotrimeric copper-containing nitrite reductase ( NiR) contains one type-1 and one type-2 copper center per monomer. Electrons enter through the type-1 site and are shuttled to the type-2 site where nitrite is reduced to nitric oxide. To investigate the catalytic mechanism of NiR the effects of

  5. Sequential defense against random and intentional attacks in complex networks

    Science.gov (United States)

    Chen, Pin-Yu; Cheng, Shin-Ming

    2015-02-01

    Network robustness against attacks is one of the most fundamental researches in network science as it is closely associated with the reliability and functionality of various networking paradigms. However, despite the study on intrinsic topological vulnerabilities to node removals, little is known on the network robustness when network defense mechanisms are implemented, especially for networked engineering systems equipped with detection capabilities. In this paper, a sequential defense mechanism is first proposed in complex networks for attack inference and vulnerability assessment, where the data fusion center sequentially infers the presence of an attack based on the binary attack status reported from the nodes in the network. The network robustness is evaluated in terms of the ability to identify the attack prior to network disruption under two major attack schemes, i.e., random and intentional attacks. We provide a parametric plug-in model for performance evaluation on the proposed mechanism and validate its effectiveness and reliability via canonical complex network models and real-world large-scale network topology. The results show that the sequential defense mechanism greatly improves the network robustness and mitigates the possibility of network disruption by acquiring limited attack status information from a small subset of nodes in the network.

  6. The pursuit of balance in sequential randomized trials

    Directory of Open Access Journals (Sweden)

    Raymond P. Guiteras

    2016-06-01

    Full Text Available In many randomized trials, subjects enter the sample sequentially. Because the covariates for all units are not known in advance, standard methods of stratification do not apply. We describe and assess the method of DA-optimal sequential allocation (Atkinson, 1982 for balancing stratification covariates across treatment arms. We provide simulation evidence that the method can provide substantial improvements in precision over commonly employed alternatives. We also describe our experience implementing the method in a field trial of a clean water and handwashing intervention in Dhaka, Bangladesh, the first time the method has been used. We provide advice and software for future researchers.

  7. Sequential time interleaved random equivalent sampling for repetitive signal

    Science.gov (United States)

    Zhao, Yijiu; Liu, Jingjing

    2016-12-01

    Compressed sensing (CS) based sampling techniques exhibit many advantages over other existing approaches for sparse signal spectrum sensing; they are also incorporated into non-uniform sampling signal reconstruction to improve the efficiency, such as random equivalent sampling (RES). However, in CS based RES, only one sample of each acquisition is considered in the signal reconstruction stage, and it will result in more acquisition runs and longer sampling time. In this paper, a sampling sequence is taken in each RES acquisition run, and the corresponding block measurement matrix is constructed using a Whittaker-Shannon interpolation formula. All the block matrices are combined into an equivalent measurement matrix with respect to all sampling sequences. We implemented the proposed approach with a multi-cores analog-to-digital converter (ADC), whose ADC cores are time interleaved. A prototype realization of this proposed CS based sequential random equivalent sampling method has been developed. It is able to capture an analog waveform at an equivalent sampling rate of 40 GHz while sampled at 1 GHz physically. Experiments indicate that, for a sparse signal, the proposed CS based sequential random equivalent sampling exhibits high efficiency.

  8. Reverse sequential therapy achieves a similar eradication rate as standard sequential therapy for Helicobacter pylori eradication: a randomized controlled trial.

    Science.gov (United States)

    Tsay, Feng-Woei; Wu, Deng-Chyang; Kao, Sung-Shuo; Tsai, Tzung-Jium; Lai, Kwok-Hung; Cheng, Jin-Shiung; Chan, Hoi-Hung; Wang, Huay-Min; Tsai, Wei-Lun; Tseng, Hui-Hwa; Peng, Nan-Jin; Hsu, Ping-I

    2015-02-01

    Sequential therapy is a two-step therapy achieving a promising eradication rate for Helicobacter pylori infection. The rationale of sequential method has been proposed that amoxicillin weakens bacterial cell walls in the initial phase of treatment, preventing the development of drug efflux channels for clarithromycin and metronidazole used in the second phase. The aim of this prospective, randomized, controlled study was to investigate whether the efficacy of reverse sequential therapy was noninferior to sequential therapy in the treatment of H. pylori infection. From January 2009 to December 2010, consecutive H. pylori-infected patients were randomly assigned to receive either sequential therapy (a 5-day dual therapy with pantoprazole plus amoxicillin, followed by a 5-day triple therapy with pantoprazole plus clarithromycin and metronidazole) or reverse sequential therapy (a 5-day triple therapy with pantoprazole plus clarithromycin and metronidazole, followed by a 5-day dual therapy with pantoprazole plus amoxicillin). H. pylori status was examined 6 weeks after the end of treatment by rapid urease and histology or urea breath test. One hundred and twenty-two H. pylori-infected participants were randomized to receive sequential (n = 60) or reverse sequential therapy (n = 62). The eradication rates, by intention-to-treat analysis, were similar: 91.9% (95% confidence interval (CI): 85.1-98.7%) for sequential therapy and 96.7% (95% CI: 92.2-101.2%) for reverse sequential therapy (p = .44). Per-protocol analysis also showed similar results: 91.8% (95% CI: 84.9-98.7%) for sequential group and 96.7% (95% CI: 92.2-101.2%) for reverse sequential therapy (p = .43). The two treatments exhibited comparable frequencies of adverse events (11.3% vs 6.7%, respectively) and drug compliance (98.4% vs 100%, respectively). The overall resistance rates of antibiotics were clarithromycin 10.5%, amoxicillin 0%, and metronidazole 44.2% of patients, respectively. The dual

  9. Sequential multiple assignment randomization trials with enrichment design.

    Science.gov (United States)

    Liu, Ying; Wang, Yuanjia; Zeng, Donglin

    2017-06-01

    Sequential multiple assignment randomization trial (SMART) is a powerful design to study Dynamic Treatment Regimes (DTRs) and allows causal comparisons of DTRs. To handle practical challenges of SMART, we propose a SMART with Enrichment (SMARTER) design, which performs stage-wise enrichment for SMART. SMARTER can improve design efficiency, shorten the recruitment period, and partially reduce trial duration to make SMART more practical with limited time and resource. Specifically, at each subsequent stage of a SMART, we enrich the study sample with new patients who have received previous stages' treatments in a naturalistic fashion without randomization, and only randomize them among the current stage treatment options. One extreme case of the SMARTER is to synthesize separate independent single-stage randomized trials with patients who have received previous stage treatments. We show data from SMARTER allows for unbiased estimation of DTRs as SMART does under certain assumptions. Furthermore, we show analytically that the efficiency gain of the new design over SMART can be significant especially when the dropout rate is high. Lastly, extensive simulation studies are performed to demonstrate performance of SMARTER design, and sample size estimation in a scenario informed by real data from a SMART study is presented. © 2016, The International Biometric Society.

  10. Sequential methods for random-effects meta-analysis

    Science.gov (United States)

    Higgins, Julian P T; Whitehead, Anne; Simmonds, Mark

    2011-01-01

    Although meta-analyses are typically viewed as retrospective activities, they are increasingly being applied prospectively to provide up-to-date evidence on specific research questions. When meta-analyses are updated account should be taken of the possibility of false-positive findings due to repeated significance tests. We discuss the use of sequential methods for meta-analyses that incorporate random effects to allow for heterogeneity across studies. We propose a method that uses an approximate semi-Bayes procedure to update evidence on the among-study variance, starting with an informative prior distribution that might be based on findings from previous meta-analyses. We compare our methods with other approaches, including the traditional method of cumulative meta-analysis, in a simulation study and observe that it has Type I and Type II error rates close to the nominal level. We illustrate the method using an example in the treatment of bleeding peptic ulcers. Copyright © 2010 John Wiley & Sons, Ltd. PMID:21472757

  11. A sequential binding mechanism in a PDZ domain

    DEFF Research Database (Denmark)

    Chi, Celestine N; Bach, Anders; Engström, Åke

    2009-01-01

    of interaction, in particular for single-domain proteins. Here, we found that the PDZ2 domain of SAP97 binds its ligand via a sequential (induced fit) mechanism. We performed binding experiments using SAP97 PDZ2 and peptide ligands and observed biphasic kinetics with the stopped-flow technique, indicating...... that ligand binding involves at least a two-step process. By using an ultrarapid continuous-flow mixer, we then detected a hyperbolic dependence of binding rate constants on peptide concentration, corroborating the two-step binding mechanism. Furthermore, we found a similar dependence of the rate constants...

  12. Encoding Sequential Information in Semantic Space Models: Comparing Holographic Reduced Representation and Random Permutation

    OpenAIRE

    Recchia, Gabriel; Sahlgren, Magnus; Kanerva, Pentti; Jones, Michael N.

    2015-01-01

    Circular convolution and random permutation have each been proposed as neurally plausible binding operators capable of encoding sequential information in semantic memory. We perform several controlled comparisons of circular convolution and random permutation as means of encoding paired associates as well as encoding sequential information. Random permutations outperformed convolution with respect to the number of paired associates that can be reliably stored in a single memory trace. Perform...

  13. A randomized sequential trial of creatine in amyotrophic lateral sclerosis

    NARCIS (Netherlands)

    Groeneveld, G. J.; Veldink, Jan H.; van der Tweel, Ingeborg; Kalmijn, Sandra; Beijer, Cornelis; de Visser, Marianne; Wokke, John H. J.; Franssen, Hessel; van den Berg, Leonard H.

    2003-01-01

    Amyotrophic lateral sclerosis (ALS) is a fatal disease with no cure. In a transgenic mouse model of ALS, creatine monohydrate showed a promising increase in survival. We performed a double-blind, placebo-controlled, sequential clinical trial to assess the effect of creatine monohydrate on survival

  14. Sequential causal inference: application to randomized trials of adaptive treatment strategies.

    Science.gov (United States)

    Dawson, Ree; Lavori, Philip W

    2008-05-10

    Clinical trials that randomize subjects to decision algorithms, which adapt treatments over time according to individual response, have gained considerable interest as investigators seek designs that directly inform clinical decision making. We consider designs in which subjects are randomized sequentially at decision points, among adaptive treatment options under evaluation. We present a sequential method to estimate the comparative effects of the randomized adaptive treatments, which are formalized as adaptive treatment strategies. Our causal estimators are derived using Bayesian predictive inference. We use analytical and empirical calculations to compare the predictive estimators to (i) the 'standard' approach that allocates the sequentially obtained data to separate strategy-specific groups as would arise from randomizing subjects at baseline; (ii) the semi-parametric approach of marginal mean models that, under appropriate experimental conditions, provides the same sequential estimator of causal differences as the proposed approach. Simulation studies demonstrate that sequential causal inference offers substantial efficiency gains over the standard approach to comparing treatments, because the predictive estimators can take advantage of the monotone structure of shared data among adaptive strategies. We further demonstrate that the semi-parametric asymptotic variances, which are marginal 'one-step' estimators, may exhibit significant bias, in contrast to the predictive variances. We show that the conditions under which the sequential method is attractive relative to the other two approaches are those most likely to occur in real studies.

  15. Sequential invasive-noninvasive mechanical ventilation weaning strategy for patients after tracheostomy

    National Research Council Canada - National Science Library

    Xue-xue Pu Jiong Wang Xue-bo Yan Xue-qin Jiang

    2015-01-01

    ...: Fifty patients including 24 patients with withdrawal of mechanical ventilation(conventional group) and 26 patients with sequential invasive-noninvasive weaning by directly plugging of tracheostomy...

  16. Decentralized enforcement, sequential bargaining, and the clean development mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Hovi, Jon

    2001-07-01

    While there is a vast literature both on international bargaining and on how international agreements can be enforced, very little work has been done on how bargaining and enforcement interact. An important exception is Fearon (1998), who models international cooperation as a two-stage process in which the bargaining process is constrained by a need for decentralized enforcement (meaning that the agreement must be enforced by the parties themselves rather than a third party, such as a court). Using the Clean Development Mechanism as an example, the present paper proposes a different model of this kind of interaction. The model follows Fearon's in so far as we both use the infinitely repeated Prisoners' Dilemma to capture the enforcement phase of the game. However, while Fearon depicts the bargaining stage as a War of Attrition, the present model sees that stage as a sequential bargaining game of the Staahl-Rubinstein type. The implications of the present model are compared both to those of the Staahl-Rubinstein model and to those of the Fearon model. A surprising conclusion is that a need for decentralized enforcement tends to make the bargaining outcome more symmetrical than otherwise. Thus, the impact of bargaining power is actually smaller when the resulting agreement must be enforced by the parties themselves than it is if enforcement is taken care of by a third party. (author)

  17. Consistency of self-reported alcohol consumption on randomized and sequential alcohol purchase tasks

    Directory of Open Access Journals (Sweden)

    Michael eAmlung

    2012-07-01

    Full Text Available Behavioral economic demand for addictive substances is commonly assessed via purchase tasks that measure estimated drug consumption at a range of prices. Purchase tasks typically use escalating prices in sequential order, which may influence performance by providing explicit price reference points. This study investigated the consistency of value preferences on two alcohol purchase tasks (APTs that used either a randomized or sequential price order (price range: free to $30 per drink in a sample of ninety-one young adult monthly drinkers. Randomization of prices significantly reduced relative response consistency (p < .01, although absolute consistency was high for both versions (>95%. Self-reported alcohol consumption across prices and indices of demand were highly similar across versions, although a few notable exceptions were found. These results suggest generally high consistency and overlapping performance between randomized and sequential price assessment. Implications for the behavioral economics literature and priorities for future research are discussed.

  18. Encoding Sequential Information in Semantic Space Models: Comparing Holographic Reduced Representation and Random Permutation

    Directory of Open Access Journals (Sweden)

    Gabriel Recchia

    2015-01-01

    Full Text Available Circular convolution and random permutation have each been proposed as neurally plausible binding operators capable of encoding sequential information in semantic memory. We perform several controlled comparisons of circular convolution and random permutation as means of encoding paired associates as well as encoding sequential information. Random permutations outperformed convolution with respect to the number of paired associates that can be reliably stored in a single memory trace. Performance was equal on semantic tasks when using a small corpus, but random permutations were ultimately capable of achieving superior performance due to their higher scalability to large corpora. Finally, “noisy” permutations in which units are mapped to other units arbitrarily (no one-to-one mapping perform nearly as well as true permutations. These findings increase the neurological plausibility of random permutations and highlight their utility in vector space models of semantics.

  19. Encoding sequential information in semantic space models: comparing holographic reduced representation and random permutation.

    Science.gov (United States)

    Recchia, Gabriel; Sahlgren, Magnus; Kanerva, Pentti; Jones, Michael N

    2015-01-01

    Circular convolution and random permutation have each been proposed as neurally plausible binding operators capable of encoding sequential information in semantic memory. We perform several controlled comparisons of circular convolution and random permutation as means of encoding paired associates as well as encoding sequential information. Random permutations outperformed convolution with respect to the number of paired associates that can be reliably stored in a single memory trace. Performance was equal on semantic tasks when using a small corpus, but random permutations were ultimately capable of achieving superior performance due to their higher scalability to large corpora. Finally, "noisy" permutations in which units are mapped to other units arbitrarily (no one-to-one mapping) perform nearly as well as true permutations. These findings increase the neurological plausibility of random permutations and highlight their utility in vector space models of semantics.

  20. A Bayesian sequential design with adaptive randomization for 2-sided hypothesis test.

    Science.gov (United States)

    Yu, Qingzhao; Zhu, Lin; Zhu, Han

    2017-11-01

    Bayesian sequential and adaptive randomization designs are gaining popularity in clinical trials thanks to their potentials to reduce the number of required participants and save resources. We propose a Bayesian sequential design with adaptive randomization rates so as to more efficiently attribute newly recruited patients to different treatment arms. In this paper, we consider 2-arm clinical trials. Patients are allocated to the 2 arms with a randomization rate to achieve minimum variance for the test statistic. Algorithms are presented to calculate the optimal randomization rate, critical values, and power for the proposed design. Sensitivity analysis is implemented to check the influence on design by changing the prior distributions. Simulation studies are applied to compare the proposed method and traditional methods in terms of power and actual sample sizes. Simulations show that, when total sample size is fixed, the proposed design can obtain greater power and/or cost smaller actual sample size than the traditional Bayesian sequential design. Finally, we apply the proposed method to a real data set and compare the results with the Bayesian sequential design without adaptive randomization in terms of sample sizes. The proposed method can further reduce required sample size. Copyright © 2017 John Wiley & Sons, Ltd.

  1. Sequential selection of random vectors under a sum constraint

    OpenAIRE

    Stanke, Mario

    2004-01-01

    We observe a sequence X1,X2,...,Xn of independent and identically distributed coordinatewise nonnegative d-dimensional random vectors. When a vector is observed it can either be selected or rejected but once made this decision is final. In each coordinate the sum of the selected vectors must not exceed a given constant. The problem is to find a selection policy that maximizes the expected number of selected vectors. For a general absolutely continuous distribution of t...

  2. Effectiveness of the random sequential absorption algorithm in the analysis of volume elements with nanoplatelets

    DEFF Research Database (Denmark)

    Pontefisso, Alessandro; Zappalorto, Michele; Quaresimin, Marino

    2016-01-01

    In this work, a study of the Random Sequential Absorption (RSA) algorithm in the generation of nanoplatelet Volume Elements (VEs) is carried out. The effect of the algorithm input parameters on the reinforcement distribution is studied through the implementation of statistical tools, showing...

  3. Effect of sequential mechanical ventilation on cardiac function, endothelial injury and oxidative stress response in patients with cor pulmonale

    Directory of Open Access Journals (Sweden)

    Yuan-Zeng He

    2017-08-01

    Full Text Available Objective: To study the effect of sequential mechanical ventilation on cardiac function, endothelial injury and oxidative stress response in patients with cor pulmonale (CCP. Methods: Patients with cor pulmonale complicated by respiratory failure who were treated in Dongfeng People’s Hospital between May 2014 and February 2017 were selected and randomly divided into the sequential group who received sequential mechanical ventilation combined with conventional therapy and the control group who received invasive positive pressure ventilation combined with conventional therapy. The serum levels of cardiac functionrelated neurohumoral indicators, endothelial injury indicators and oxidative stress response indicators were detected before treatment as well as 3 d and 7 d after treatment. Results: 3 d and 7 d after treatment, serum NT-proBNP, Copeptin, Ang-II, ALD, ET-1, vWF, sST2 levels of both groups of patients were significantly lower than those before treatment while NO, SOD, GSH-Px and T-AOC levels were significantly higher than those before treatment; serum NTproBNP, Copeptin, Ang-II, ALD, ET-1, vWF, sST2, NO, 8-iso-PGF2a, MDA, SOD, GSH-Px and T-AOC levels of sequential group 3 d after treatment were not significantly different from those of control group; serum NT-proBNP, Copeptin, Ang-II, ALDET-1, vWF, sST2, 8-iso- PGF2a and MDA levels of sequential group 7 d after treatment were significantly lower than those of control group while NO, SOD, GSH-Px and T-AOC levels were significantly higher than those of control group. Conclusion: Sequential mechanical ventilation for cor pulmonale can improve the cardiac function and reduce the degree of endothelial injury and oxidative stress response.

  4. Randomness in Classical Mechanics and Quantum Mechanics

    Science.gov (United States)

    Volovich, Igor V.

    2011-03-01

    The Copenhagen interpretation of quantum mechanics assumes the existence of the classical deterministic Newtonian world. We argue that in fact the Newton determinism in classical world does not hold and in the classical mechanics there is fundamental and irreducible randomness. The classical Newtonian trajectory does not have a direct physical meaning since arbitrary real numbers are not observable. There are classical uncertainty relations: Δ q>0 and Δ p>0, i.e. the uncertainty (errors of observation) in the determination of coordinate and momentum is always positive (non zero). A "functional" formulation of classical mechanics was suggested. The fundamental equation of the microscopic dynamics in the functional approach is not the Newton equation but the Liouville equation for the distribution function of the single particle. Solutions of the Liouville equation have the property of delocalization which accounts for irreversibility. The Newton equation in this approach appears as an approximate equation describing the dynamics of the average values of the position and momenta for not too long time intervals. Corrections to the Newton trajectories are computed. An interpretation of quantum mechanics is attempted in which both classical and quantum mechanics contain fundamental randomness. Instead of an ensemble of events one introduces an ensemble of observers.

  5. Comparing cluster-level dynamic treatment regimens using sequential, multiple assignment, randomized trials: Regression estimation and sample size considerations.

    Science.gov (United States)

    NeCamp, Timothy; Kilbourne, Amy; Almirall, Daniel

    2017-08-01

    Cluster-level dynamic treatment regimens can be used to guide sequential treatment decision-making at the cluster level in order to improve outcomes at the individual or patient-level. In a cluster-level dynamic treatment regimen, the treatment is potentially adapted and re-adapted over time based on changes in the cluster that could be impacted by prior intervention, including aggregate measures of the individuals or patients that compose it. Cluster-randomized sequential multiple assignment randomized trials can be used to answer multiple open questions preventing scientists from developing high-quality cluster-level dynamic treatment regimens. In a cluster-randomized sequential multiple assignment randomized trial, sequential randomizations occur at the cluster level and outcomes are observed at the individual level. This manuscript makes two contributions to the design and analysis of cluster-randomized sequential multiple assignment randomized trials. First, a weighted least squares regression approach is proposed for comparing the mean of a patient-level outcome between the cluster-level dynamic treatment regimens embedded in a sequential multiple assignment randomized trial. The regression approach facilitates the use of baseline covariates which is often critical in the analysis of cluster-level trials. Second, sample size calculators are derived for two common cluster-randomized sequential multiple assignment randomized trial designs for use when the primary aim is a between-dynamic treatment regimen comparison of the mean of a continuous patient-level outcome. The methods are motivated by the Adaptive Implementation of Effective Programs Trial which is, to our knowledge, the first-ever cluster-randomized sequential multiple assignment randomized trial in psychiatry.

  6. Classification of epileptic EEG signals based on simple random sampling and sequential feature selection

    OpenAIRE

    Ghayab, Hadi Ratham Al; Li, Yan; Abdulla, Shahab; Diykh, Mohammed; Wan, Xiangkui

    2016-01-01

    Electroencephalogram (EEG) signals are used broadly in the medical fields. The main applications of EEG signals are the diagnosis and treatment of diseases such as epilepsy, Alzheimer, sleep problems and so on. This paper presents a new method which extracts and selects features from multi-channel EEG signals. This research focuses on three main points. Firstly, simple random sampling (SRS) technique is used to extract features from the time domain of EEG signals. Secondly, the sequential fea...

  7. Randomized trial of oral versus sequential IV/oral antibiotic for acute pyelonephritis in children.

    Science.gov (United States)

    Bocquet, Nathalie; Sergent Alaoui, Aline; Jais, Jean-Pierre; Gajdos, Vincent; Guigonis, Vincent; Lacour, Bernard; Chéron, Gérard

    2012-02-01

    To confirm whether oral antibiotic treatment is as efficacious as sequential intravenous/oral antibiotic treatment in the prevention of renal scarring in children with acute pyelonephritis and scintigraphy-documented acute lesions. In a prospective multicenter trial, children aged 1 to 36 months with their first case of acute pyelonephritis, a serum procalcitonin concentration ≥0.5 ng/mL, no known uropathy, and a normal ultrasound exam were randomized into 2 treatment groups. They received either oral cefixime for 10 days or intravenous ceftriaxone for 4 days followed by oral cefixime for 6 days. Patients with acute renal lesions detected on early dimercaptosuccinic acid scintigraphy underwent a follow-up scintigraphy 6 to 8 months later. The study included 171 infants and children. There were no significant differences between the 2 groups in any clinical characteristic. Initial scintigraphy results were abnormal for 119 children. Ninety-six children were measured for renal scarring at the follow-up scintigraphy (per protocol analysis population). The incidence of renal scarring was 30.8% in the oral treatment group and 27.3% for children who received the sequential treatment. Although this trial does not statistically demonstrate the noninferiority of oral treatment compared with the sequential treatment, our study confirmed the results of previously published reports and therefore supports the use of an oral antibiotic treatment of primary episodes of acute pyelonephritis in infants and young children.

  8. Comparison of hybrid and sequential therapies for Helicobacter pylori eradication in Iran: a prospective randomized trial.

    Science.gov (United States)

    Sardarian, Hossein; Fakheri, Hafez; Hosseini, Vahid; Taghvaei, Tarang; Maleki, Iradj; Mokhtare, Marjan

    2013-04-01

    The eradication of Helicobacter pylori has been always a concern. In the present study, we aimed to compare two novel treatments in Iran. Four hundred and twenty patients with peptic ulcer and naïve H. pylori infection were randomized in the study. Two hundred and ten patients received hybrid therapy: pantoprazole 40 mg/b.i.d. and amoxicillin 1 g/b.i.d. for 14 days plus 500 mg clarithromycin and 500 mg tinidazole, both twice daily for the last 7 days. The other 210 patients received sequential therapy: 40 mg pantoprazole/b.i.d. for 10 days and 1 g amoxicillin/b.i.d. for the first 5 days, followed by 500 mg clarithromycin/b.i.d. and 500 mg tinidazole/b.i.d. for the last 5 days. C¹⁴-urea breath test was performed 8 weeks after the treatment. Three hundred and ninety-six patients (197 patients in the hybrid group and 199 patients in the sequential group) completed the study. The compliance rates were 96.7 and 98.6% for the two groups, respectively. The intention-to-treat eradication rate was 89.5% (95% CI = 85.4-93.6) for the hybrid group and 76.7% (95% CI = 71-82.4) for the sequential group (p = .001), and the per-protocol eradication rates were 92.9% (95% CI = 89.2-96.5) and 79.9% (95% CI = 74.1-85.4) for the hybrid and sequential groups (p = .001), respectively. Severe adverse effects were observed in 2.4% of patients in the hybrid group and 3.8% of those in the sequential group. According to our results, sequential regimen does not seem to be an appropriate therapy for H. pylori eradication in the Iranian population, whereas hybrid therapy showed to be more effective. However, considering the high cost of clarithromycin in Iran, we recommend further studies to compare hybrid therapy with bismuth-containing regimens or to assess the effects of hybrid therapies with periods shorter than 14 days. © 2012 Blackwell Publishing Ltd.

  9. Early embryo development in a sequential versus single medium: a randomized study

    Directory of Open Access Journals (Sweden)

    D'Hooghe Thomas M

    2010-07-01

    Full Text Available Abstract Background The success of in vitro fertilization techniques is defined by multiple factors including embryo culture conditions, related to the composition of the culture medium. In view of the lack of solid scientific data and in view of the current general belief that sequential media are superior to single media, the aim of this randomized study was to compare the embryo quality in two types of culture media. Methods In this study, the embryo quality on day 3 was measured as primary outcome. In total, 147 patients younger than 36 years treated with IVF/ICSI during the first or second cycle were included in this study. Embryos were randomly cultured in a sequential (group A or a single medium (group B to compare the embryo quality on day 1, day 2 and day 3. The embryo quality was compared in both groups using a Chi-square test with a significance level of 0.05. Results At day 1, the percentage of embryos with a cytoplasmic halo was higher in group B (46% than in group A (32%. At day 2, number of blastomeres, degree of fragmentation and the percentage of unequally sized blastomeres were higher in group B than in group A. At day 3, a higher percentage of embryos had a higher number of blastomeres and unequally sized blastomeres in group B. The number of good quality embryos (GQE was comparable in both groups. The embryo utilization rate was higher in group B (56% compared to group A (49%. Conclusions Although, no significant difference in the number of GQE was found in both media, the utilization rate was significantly higher when the embryos were cultured in the single medium compared to the sequential medium. The results of this study have a possible positive effect on the cumulative cryo-augmented pregnancy rate. Trial registration number NCT01094314

  10. Quadruple, sequential, and concomitant first-line therapies for H. pylori eradication: a prospective, randomized study.

    Science.gov (United States)

    De Francesco, Vincenzo; Pontone, Stefano; Bellesia, Annamaria; Serviddio, Gaetano; Panetta, Cristina; Palma, Rossella; Zullo, Angelo

    2017-10-18

    Current Italian guidelines recommend 10-day bismuth-based or bismuth-free (sequential and concomitant) regimens for first-line H. pylori eradication. However, comparison among these regimens is lacking in our country. To perform a 'head-to-head' comparison among these three therapies as first-line treatment for H. pylori eradication in clinical practice. This was a prospective, open-label randomized study enrolling consecutive patients diagnosed with H. pylori infection never previously treated. Patients were randomized to receive one of the following 10-day therapies: (a) Bismuth-based therapy: esomeprazole 20mg b.i.d and Pylera 3 tablets q.i.d; (b) Concomitant therapy: esomeprazole 20mg plus amoxicyllin 1,000mg, clarithromycin 500mg and tinidazole 500mg (all b.i.d.), and (c) Sequential therapy: esomeprazole 20mg plus amoxicyllin 1,000mg for 5days followed by esomeprazole 20mg plus clarithromycin 500mg and tinidazole 500mg for 5days (all b.i.d). H. pylori eradication was assessed by using UBT 4-6 weeks after the end of therapy. Overall, 187 patients were enrolled. The eradication rates achieved with Pylera, concomitant and sequential were 85.2%, 95.2%, and 93.6%, respectively, at intention to treat, and 94.5%, 96.7%, and 95.1% at per protocol analyses, without a statistically significant difference. The incidence of severe side-effects was higher with the bismuth-based therapy than with the two bismuth-free regimens (9.8% vs 1.6%; p=0.046). Bismuth-based and bismuth-free therapies are equally effective for first-line H. pylori eradication. However, bismuth therapy was more frequently interrupted for side-effects than bismuth-free therapies. Copyright © 2017 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  11. Sequential change detection and monitoring of temporal trends in random-effects meta-analysis.

    Science.gov (United States)

    Dogo, Samson Henry; Clark, Allan; Kulinskaya, Elena

    2017-06-01

    Temporal changes in magnitude of effect sizes reported in many areas of research are a threat to the credibility of the results and conclusions of meta-analysis. Numerous sequential methods for meta-analysis have been proposed to detect changes and monitor trends in effect sizes so that meta-analysis can be updated when necessary and interpreted based on the time it was conducted. The difficulties of sequential meta-analysis under the random-effects model are caused by dependencies in increments introduced by the estimation of the heterogeneity parameter τ2 . In this paper, we propose the use of a retrospective cumulative sum (CUSUM)-type test with bootstrap critical values. This method allows retrospective analysis of the past trajectory of cumulative effects in random-effects meta-analysis and its visualization on a chart similar to CUSUM chart. Simulation results show that the new method demonstrates good control of Type I error regardless of the number or size of the studies and the amount of heterogeneity. Application of the new method is illustrated on two examples of medical meta-analyses. © 2016 The Authors. Research Synthesis Methods published by John Wiley & Sons Ltd. © 2016 The Authors. Research Synthesis Methods published by John Wiley & Sons Ltd.

  12. Nonstandard convergence to jamming in random sequential adsorption: The case of patterned one-dimensional substrates

    Science.gov (United States)

    Verma, Arjun; Privman, Vladimir

    2018-02-01

    We study approach to the large-time jammed state of the deposited particles in the model of random sequential adsorption. The convergence laws are usually derived from the argument of Pomeau which includes the assumption of the dominance, at large enough times, of small landing regions into each of which only a single particle can be deposited without overlapping earlier deposited particles and which, after a certain time are no longer created by depositions in larger gaps. The second assumption has been that the size distribution of gaps open for particle-center landing in this large-time small-gaps regime is finite in the limit of zero gap size. We report numerical Monte Carlo studies of a recently introduced model of random sequential adsorption on patterned one-dimensional substrates that suggest that the second assumption must be generalized. We argue that a region exists in the parameter space of the studied model in which the gap-size distribution in the Pomeau large-time regime actually linearly vanishes at zero gap sizes. In another region, the distribution develops a threshold property, i.e., there are no small gaps below a certain gap size. We discuss the implications of these findings for new asymptotic power-law and exponential-modified-by-a-power-law convergences to jamming in irreversible one-dimensional deposition.

  13. Start-up designs for response-adaptive randomization procedures with sequential estimation.

    Science.gov (United States)

    Haines, Linda M; Sadiq, Hassan

    2015-09-20

    Response-adaptive randomization procedures are appropriate for clinical trials in which two or more treatments are to be compared, patients arrive sequentially and the response of each patient is recorded before the next patient arrives. However, for those procedures that involve sequential estimation of model parameters, start-up designs are commonly required in order to provide initial estimates of the parameters. In this paper, a suite of such start-up designs for two treatments and binary patient responses are considered and compared in terms of the numbers of patients required in order to give meaningful parameters estimates, the number of patients allocated to the better treatment, and the bias in the parameter estimates. It is shown that permuted block designs with blocks of size 4 are to be preferred over a wide range of parameter values. For the case of two treatments, normal responses and selected start-up procedures, a design incorporating complete randomization followed appropriately by repeats of one of the treatments yields the minimum expected number of patients and is to be preferred. Copyright © 2015 John Wiley & Sons, Ltd.

  14. Glassy behavior and jamming of a random walk process for sequentially satisfying a constraint satisfaction formula

    Science.gov (United States)

    Zhou, Haijun

    2010-02-01

    Random K-satisfiability (K-SAT) is a model system for studying typical-case complexity of combinatorial optimization. Recent theoretical and simulation work revealed that the solution space of a random K-SAT formula has very rich structures, including the emergence of solution communities within single solution clusters. In this paper we investigate the influence of the solution space landscape to a simple stochastic local search process SEQSAT, which satisfies a K-SAT formula in a sequential manner. Before satisfying each newly added clause, SEQSAT walk randomly by single-spin flips in a solution cluster of the old subformula. This search process is efficient when the constraint density α of the satisfied subformula is less than certain value αcm; however it slows down considerably as α> αcm and finally reaches a jammed state at α≈αj. The glassy dynamical behavior of SEQSAT for α≥αcm probably is due to the entropic trapping of various communities in the solution cluster of the satisfied subformula. For random 3-SAT, the jamming transition point αj is larger than the solution space clustering transition point αd, and its value can be predicted by a long-range frustration mean-field theory. For random K-SAT with K ≥ 4, however, our simulation results indicate that αj = αd. The relevance of this work for understanding the dynamic properties of glassy systems is also discussed.

  15. Sorption mechanisms of sulfamethazine to soil humin and its subfractions after sequential treatments

    NARCIS (Netherlands)

    Guo, X.; Shen, X.; Zhang, M.; Zhang, H.; Chen, W.; Wang, H.; Koelmans, A.A.; Cornelissen, G.; Tao, S.; Wang, X.

    2017-01-01

    Sorption mechanisms of an antibiotic sulfamethazine (SMT) to humin (HM) isolated from a peat soil and its subfractions after sequential treatments were examined. The treatments of HM included removal of ash, O-alkyl carbon, lipid, and lignin components. The HF/HCl de-ashing treatment removed a large

  16. Minimal sufficient balance randomization for sequential randomized controlled trial designs: results from the ESCAPE trial.

    Science.gov (United States)

    Sajobi, Tolulope T; Singh, Gurbakhshash; Lowerison, Mark W; Engbers, Jordan; Menon, Bijoy K; Demchuk, Andrew M; Goyal, Mayank; Hill, Michael D

    2017-11-02

    We describe the implementation of minimal sufficient balance randomization, a covariate-adaptive randomization technique, used for the "Endovascular treatment for Small Core and Anterior circulation Proximal occlusion with Emphasis on minimizing CT to recanalization times" (ESCAPE) trial. The ESCAPE trial is a prospective, multicenter, randomized clinical trial that enrolled subjects with the following main inclusion criteria: less than 12 h from symptom onset, age 18 years or older, baseline NIHSS score > 5, ASPECTS score > 5 and computed tomography angiography (CTA) evidence of carotid T/L or M1-segment middle cerebral artery (MCA) occlusion, and at least moderate collaterals by CTA. Patients were randomized using a real-time, dynamic, Internet-based, minimal sufficient balance randomization method that balanced the study arms with respect to baseline covariates including age, sex, baseline NIHSS score, site of arterial occlusion, baseline ASPECTS score and treatment with intravenously administered alteplase. Permutation-based tests of group differences confirmed group balance across several baseline covariates including sex (p = 1.00), baseline NIHSS score (p = 0.95), site of arterial occlusion (p = 1.00), baseline ASPECTS score (p = 0.28), treatment with intravenously administered alteplase (p = 0.31), and age (p = 0.67). Results from the ESCAPE trial demonstrate the feasibility and the benefit of this covariate adaptive randomization scheme in small-sample trials and for data monitoring endeavors. ESCAPE trial - NCT01778335 - at www.clinicaltrials.gov . Registered on 29 January 2013.

  17. Symmetry effects in reversible random sequential adsorption on a triangular lattice.

    Science.gov (United States)

    Budinski-Petković, Lj; Petković, M; Jaksić, Z M; Vrhovac, S B

    2005-10-01

    Reversible random sequential adsorption of objects of various shapes on a two-dimensional triangular lattice is studied numerically by means of Monte Carlo simulations. The growth of the coverage rho(t) above the jamming limit to its steady-state value rho(infinity) is described by a pattern rho(t) = rho(infinity - deltarhoE(beta)[-(t/tau)beta], where E(beta) denotes the Mittag-Leffler function of order beta element of (0, 1). The parameter tau is found to decay with the desorption probability P_ according to a power law tau = AP_(-gamma). The exponent gamma is the same for all shapes, gamma = 1.29 +/- 0.01, but the parameter A depends only on the order of symmetry axis of the shape. Finally, we present the possible relevance of the model to the compaction of granular objects of various shapes.

  18. Classification of epileptic EEG signals based on simple random sampling and sequential feature selection.

    Science.gov (United States)

    Ghayab, Hadi Ratham Al; Li, Yan; Abdulla, Shahab; Diykh, Mohammed; Wan, Xiangkui

    2016-06-01

    Electroencephalogram (EEG) signals are used broadly in the medical fields. The main applications of EEG signals are the diagnosis and treatment of diseases such as epilepsy, Alzheimer, sleep problems and so on. This paper presents a new method which extracts and selects features from multi-channel EEG signals. This research focuses on three main points. Firstly, simple random sampling (SRS) technique is used to extract features from the time domain of EEG signals. Secondly, the sequential feature selection (SFS) algorithm is applied to select the key features and to reduce the dimensionality of the data. Finally, the selected features are forwarded to a least square support vector machine (LS_SVM) classifier to classify the EEG signals. The LS_SVM classifier classified the features which are extracted and selected from the SRS and the SFS. The experimental results show that the method achieves 99.90, 99.80 and 100 % for classification accuracy, sensitivity and specificity, respectively.

  19. Inefficiency of randomization methods that balance on stratum margins and improvements with permuted blocks and a sequential method.

    Science.gov (United States)

    Kaiser, Lee D

    2012-07-20

    Stratified permuted blocks randomization is commonly applied in clinical trials, but other randomization methods that attempt to balance treatment counts marginally for the stratification variables are able to accommodate more stratification variables. When the analysis stratifies on the cells formed by crossing the stratification variables, these other randomization methods yield treatment effect estimates with larger variance than does stratified permuted blocks. When it is truly necessary to balance the randomization on many stratification variables, it is shown how this inefficiency can be improved by using a sequential randomization method where the first level balances on the crossing of the strata used in the analysis and further stratification variables fall lower in the sequential hierarchy. Copyright © 2012 John Wiley & Sons, Ltd.

  20. Long-term sequential deferiprone-deferoxamine versus deferiprone alone for thalassaemia major patients: a randomized clinical trial

    DEFF Research Database (Denmark)

    Maggio, Aurelio; Vitrano, Angela; Capra, Marcello

    2009-01-01

    A multicentre randomized open-label trial was designed to assess the effectiveness of long-term sequential deferiprone-deferoxamine (DFO-DFP) versus DFP alone to treat thalassaemia major (TM). DFP at 75 mg/kg, divided into three oral daily doses, for 4 d/week and DFO by subcutaneous infusion (8-1...

  1. Randomized Phase II trial of nintedanib, afatinib and sequential combination in castration-resistant prostate cancer.

    Science.gov (United States)

    Molife, L Rhoda; Omlin, Aurelius; Jones, Rob J; Karavasilis, Vasilios; Bloomfield, David; Lumsden, Graeme; Fong, Peter C; Olmos, David; O'Sullivan, Joe M; Pedley, Ian; Hickish, Tamas; Jenkins, Peter; Thompson, Emilda; Oommen, Nikhil; Wheatley, Duncan; Heath, Catherine; Temple, Graham; Pelling, Katy; de Bono, Johann S

    2014-02-01

    The aim of this article was to evaluate afatinib (BIBW 2992), an ErbB family blocker, and nintedanib (BIBF 1120), a triple angiokinase inhibitor, in castration-resistant prostate cancer patients. Patients were randomized to receive nintedanib (250 mg twice daily), afatinib (40 mg once daily [q.d.]), or alternating sequential 7-day nintedanib (250 mg twice daily) and afatinib (70 mg q.d. [Combi70]), which was reduced to 40 mg q.d. (Combi40) due to adverse events. The primary end point was progression-free rate at 12 weeks. Of the 85 patients treated 46, 20, 16 and three received nintedanib, afatinib, Combi40 and Combi70, respectively. At 12 weeks, the progression-free rate was 26% (seven out of 27 patients) for nintedanib, and 0% for afatinib and Combi40 groups. Two patients had a ≥50% decline in PSA (nintedanib and the Combi40 groups). The most common drug-related adverse events were diarrhea, nausea, vomiting and lethargy. Nintedanib and/or afatinib demonstrated limited anti-tumor activity in unselected advanced castration-resistant prostate cancer patients.

  2. Random sequential adsorption of human adenovirus 2 onto polyvinylidene fluoride surface influenced by extracellular polymeric substances.

    Science.gov (United States)

    Lu, Ruiqing; Li, Qi; Nguyen, Thanh H

    2016-03-15

    Virus removal by membrane bioreactors depends on virus-membrane and virus-foulant interactions. The adsorption of human adenovirus 2 (HAdV-2) on polyvinylidene fluoride (PVDF) membrane and a major membrane foulant, extracellular polymeric substances (EPS), were measured in a quartz crystal microbalance. In 3-100mM CaCl2 solutions, irreversible adsorption of HAdV-2 was observed on both pristine and EPS-fouled PVDF surfaces. The HAdV-2 adsorption kinetics was successfully fitted with the random sequential adsorption (RSA) model. The applicability of the RSA model for HAdV-2 adsorption is confirmed by comparing the two fitting parameters, adsorption rate constant k(a) and area occupied by each adsorbed HAdV-2 particle a, with experimentally measured parameters. A linear correlation between the fitting parameter k(a) and the measured attachment efficiency was found, suggesting that the RSA model correctly describes the interaction forces dominating the HAdV-2 adsorption. By comparing the fitting parameter d(ads) with the hydrodynamic diameter of HAdV-2, we conclude that virus-virus and virus-surface interactions determine the area occupied by each adsorbed HAdV-2 particle, and thus influence the adsorption capacity. These results provide insights into virus retention and will benefit improving virus removal in membrane filtration. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Shape Universality Classes in the Random Sequential Adsorption of Nonspherical Particles

    Science.gov (United States)

    Baule, Adrian

    2017-07-01

    Random sequential adsorption (RSA) of particles of a particular shape is used in a large variety of contexts to model particle aggregation and jamming. A key feature of these models is the observed algebraic time dependence of the asymptotic jamming coverage ˜t-ν as t →∞ . However, the exact value of the exponent ν is not known apart from the simplest case of the RSA of monodisperse spheres adsorbed on a line (Renyi's seminal "car parking problem"), where ν =1 can be derived analytically. Empirical simulation studies have conjectured on a case-by-case basis that for general nonspherical particles, ν =1 /(d +d ˜ ), where d denotes the dimension of the domain, and d ˜ the number of orientational degrees of freedom of a particle. Here, we solve this long-standing problem analytically for the d =1 case—the "Paris car parking problem." We prove, in particular, that the scaling exponent depends on the particle shape, contrary to the original conjecture and, remarkably, falls into two universality classes: (i) ν =1 /(1 +d ˜ /2 ) for shapes with a smooth contact distance, e.g., ellipsoids, and (ii) ν =1 /(1 +d ˜ ) for shapes with a singular contact distance, e.g., spherocylinders and polyhedra. The exact solution explains, in particular, why many empirically observed scalings fall in between these two limits.

  4. Double-blind randomized trial of quadruple sequential Helicobacter pylori eradication therapy in asymptomatic infected children in El Paso, Texas.

    Science.gov (United States)

    Prieto-Jimenez, Carmen A; Cardenas, Victor M; Fischbach, Lori A; Mulla, Zuber D; Rivera, Jose O; Dominguez, Delfina C; Graham, David Y; Ortiz, Melchor

    2011-03-01

    We assessed the efficacy of a novel quadruple sequential 10-day eradication therapy, its compliance, and reported adverse events in a sample of asymptomatically Helicobacter pylori-infected children in El Paso, Texas, as part of a study aiming to assess the influence of this infection on the levels of markers of iron stores. Using a double-blind randomized trial design, 110 asymptomatic children ages 3 to 11 with H pylori infection were randomly assigned to receive either a 10-day course of sequential eradication therapy plus 6 weeks of iron supplementation, eradication therapy plus placebo, iron supplementation plus placebo, or placebo only. H pylori infection status was assessed ≥45 days after treatment using the urea breath test. Analyses compared the proportion of subjects cured according to assignment to and completion of the sequential eradication therapy. Intent-to-treat and per-protocol analyses indicated that 44.3% and 52.9%, respectively, of the children receiving the novel quadruple sequential therapy had their infection eradicated compared with 12.2% and 15.4% in the arms receiving iron or placebo only, respectively (P treatment. There was no difference in the cure rates of those receiving iron supplementation and those receiving placebo.

  5. Comparing cluster-level dynamic treatment regimens using sequential, multiple assignment, randomized trials: Regression estimation and sample size considerations

    OpenAIRE

    NeCamp, Timothy; Kilbourne, Amy; Almirall, Daniel

    2016-01-01

    Cluster-level dynamic treatment regimens can be used to guide sequential, intervention or treatment decision-making at the cluster level in order to improve outcomes at the individual or patient-level. In a cluster-level DTR, the intervention or treatment is potentially adapted and re-adapted over time based on changes in the cluster that could be impacted by prior intervention, including based on aggregate measures of the individuals or patients that comprise it. Cluster-randomized sequentia...

  6. Mechanism of Sequential Swallowing during Straw Drinking in Healthy Young and Older Adults

    Science.gov (United States)

    Daniels, Stephanie K.; Corey, David M.; Hadskey, Leslie D.; Legendre, Calli; Priestly, Daniel H.; Rosenbek, John C.; Foundas, Anne L.

    2004-01-01

    Recent research has revealed differences between isolated and sequential swallowing in healthy young adults; however, the influence of normal aging on sequential swallowing has not been studied. Thus, the purpose of this investigation was to examine the effects of normal aging on deglutition during sequential straw drinking. Videofluoroscopic…

  7. Improved tolerance to sequential glucose loading (Staub-Traugott effect): size and mechanisms

    DEFF Research Database (Denmark)

    Bonuccelli, Sandra; Muscelli, Elza; Gastaldelli, Amalia

    2009-01-01

    Improved glucose tolerance to sequential glucose loading (Staub-Traugott effect) is an important determinant of day-to-day glycemic exposure. Its mechanisms have not been clearly established. We recruited 17 healthy volunteers to receive two sequential oral glucose tolerance tests (OGTTs), at time...... 0 min and 180 min (Study I). The protocol was repeated on a separate day (Study II) except that plasma glucose was clamped at 8.3 mmol/l between 60 and 180 min. beta-Cell function was analyzed by mathematical modeling of C-peptide concentrations. In a subgroup, glucose kinetics were measured...... by a triple-tracer technique (infusion of [6,6-(2)H(2)]glucose and labeling of the 2 glucose loads with [1-(2)H]glucose and [U-(13)C]glucose). In both Studies I and II, the plasma glucose response to the second OGTT equaled 84 +/- 2% (P = 0.003) of the response to the first OGTT. Absolute insulin secretion...

  8. Cavity lining after excavating caries lesions: meta-analysis and trial sequential analysis of randomized clinical trials.

    Science.gov (United States)

    Schwendicke, Falk; Göstemeyer, Gerd; Gluud, Christian

    2015-11-01

    After removal of dentine caries lesions, cavity lining has been advocated. Non-clinical data support this approach, but clinical data are sparse and ambiguous. We aimed at evaluating the benefits and harms of cavity lining using meta-analysis and Trial Sequential Analysis. We included randomized clinical trials comparing restorations without versus with cavity lining for treating primary caries lesions. Only trials reporting failure (defined as need to re-retreat) after ≥1 year follow-up were included. Trial selection, data extraction, and risk of bias assessment were conducted independently by two reviewers. We conducted random-effects intention-to-treat and per-protocol meta-analyses, and Trial Sequential Analysis to control for random errors. Electronic databases (PubMed, Embase, CENTRAL) were systematically screened, and hand searches and cross-referencing performed. From 128 studies, three randomized trials (89/130 patients or teeth), all treating primary teeth, were included. The trials had high risk of bias. All trials compared no lining versus calcium hydroxide lining after selective caries removal followed by adhesive restoration. Follow-up was 36 to 53 months. Restoring the cavity without lining did not significantly affect the risk of failure (intention-to-treat relative risk (RR) (95% confidence interval) 0.71 (0.49-1.04), per-protocol RR 0.52 (0.24-1.10). According to Trial Sequential Analysis, no firm evidence was reached. The quality of evidence was very low. Strong recommendations for using cavity liners are unsubstantiated, but firm evidence for omitting lining is also unavailable. Our findings apply only to primary teeth and calcium hydroxide liner. Whilst lining is frequently performed in dental practice, very few randomized clinical trials investigated this issue. The three trials included in this review treated deciduous teeth and did not find lining with calcium hydroxide beneficial. Lining is not supported by sufficient clinical evidence

  9. Sequential bottom-up assembly of mechanically stabilized synthetic cells by microfluidics

    Science.gov (United States)

    Weiss, Marian; Frohnmayer, Johannes Patrick; Benk, Lucia Theresa; Haller, Barbara; Janiesch, Jan-Willi; Heitkamp, Thomas; Börsch, Michael; Lira, Rafael B.; Dimova, Rumiana; Lipowsky, Reinhard; Bodenschatz, Eberhard; Baret, Jean-Christophe; Vidakovic-Koch, Tanja; Sundmacher, Kai; Platzman, Ilia; Spatz, Joachim P.

    2018-01-01

    Compartments for the spatially and temporally controlled assembly of biological processes are essential towards cellular life. Synthetic mimics of cellular compartments based on lipid-based protocells lack the mechanical and chemical stability to allow their manipulation into a complex and fully functional synthetic cell. Here, we present a high-throughput microfluidic method to generate stable, defined sized liposomes termed `droplet-stabilized giant unilamellar vesicles (dsGUVs)’. The enhanced stability of dsGUVs enables the sequential loading of these compartments with biomolecules, namely purified transmembrane and cytoskeleton proteins by microfluidic pico-injection technology. This constitutes an experimental demonstration of a successful bottom-up assembly of a compartment with contents that would not self-assemble to full functionality when simply mixed together. Following assembly, the stabilizing oil phase and droplet shells are removed to release functional self-supporting protocells to an aqueous phase, enabling them to interact with physiologically relevant matrices.

  10. Sequential bottom-up assembly of mechanically stabilized synthetic cells by microfluidics.

    Science.gov (United States)

    Weiss, Marian; Frohnmayer, Johannes Patrick; Benk, Lucia Theresa; Haller, Barbara; Janiesch, Jan-Willi; Heitkamp, Thomas; Börsch, Michael; Lira, Rafael B; Dimova, Rumiana; Lipowsky, Reinhard; Bodenschatz, Eberhard; Baret, Jean-Christophe; Vidakovic-Koch, Tanja; Sundmacher, Kai; Platzman, Ilia; Spatz, Joachim P

    2017-10-16

    Compartments for the spatially and temporally controlled assembly of biological processes are essential towards cellular life. Synthetic mimics of cellular compartments based on lipid-based protocells lack the mechanical and chemical stability to allow their manipulation into a complex and fully functional synthetic cell. Here, we present a high-throughput microfluidic method to generate stable, defined sized liposomes termed 'droplet-stabilized giant unilamellar vesicles (dsGUVs)'. The enhanced stability of dsGUVs enables the sequential loading of these compartments with biomolecules, namely purified transmembrane and cytoskeleton proteins by microfluidic pico-injection technology. This constitutes an experimental demonstration of a successful bottom-up assembly of a compartment with contents that would not self-assemble to full functionality when simply mixed together. Following assembly, the stabilizing oil phase and droplet shells are removed to release functional self-supporting protocells to an aqueous phase, enabling them to interact with physiologically relevant matrices.

  11. Block urn design - a new randomization algorithm for sequential trials with two or more treatments and balanced or unbalanced allocation

    Science.gov (United States)

    Zhao, Wenle; Weng, Yanqiu

    2011-01-01

    Permuted block design is the most popular randomization method used in clinical trials, especially for trials with more than two treatments and unbalanced allocation, because of its consistent imbalance control and simplicity in implementation. However, the risk of selection biases caused by high proportion of deterministic assignments is a cause of concern. Efron’s biased coin design and Wei’s urn design provide better allocation randomness without deterministic assignments, but they do not consistently control treatment imbalances. Alternative randomization designs with improved performances have been proposed over the past few decades, including Soares and Wu’s big stick design, which has high allocation randomness, but is limited to two-treatment balanced allocation scenarios only, and Berger’s maximal procedure design which has a high allocation randomness and a potential for more general trial scenarios, but lacks the explicit function for the conditional allocation probability and is more complex to implement than most other designs. The block urn design proposed in this paper combines the advantages of existing randomization designs while overcoming their limitations. Statistical properties of the new algorithm are assessed and compared to currently available designs via analytical and computer simulation approaches. The results suggest that the block urn design simultaneously provides consistent imbalance control and high allocation randomness. It can be easily implemented for sequential clinical trials with two or more treatments and balanced or unbalanced allocation. PMID:21893215

  12. Infinite Random Graphs as Statistical Mechanical Models

    DEFF Research Database (Denmark)

    Durhuus, Bergfinnur Jøgvan; Napolitano, George Maria

    2011-01-01

    We discuss two examples of infinite random graphs obtained as limits of finite statistical mechanical systems: a model of two-dimensional dis-cretized quantum gravity defined in terms of causal triangulated surfaces, and the Ising model on generic random trees. For the former model we describe...... a relation to the so-called uniform infinite tree and results on the Hausdorff and spectral dimension of two-dimensional space-time obtained in B. Durhuus, T. Jonsson, J.F. Wheater, J. Stat. Phys. 139, 859 (2010) are briefly outlined. For the latter we discuss results on the absence of spontaneous...

  13. Trial sequential analyses of meta-analyses of complications in laparoscopic vs. small-incision cholecystectomy: more randomized patients are needed

    DEFF Research Database (Denmark)

    Keus, Frederik; Wetterslev, Jørn; Gluud, Christian

    2010-01-01

    Conclusions based on meta-analyses of randomized trials carry a status of "truth." Methodological components may identify trials with systematic errors ("bias"). Trial sequential analysis (TSA) evaluates random errors in meta-analysis. We analyzed meta-analyses on laparoscopic vs. small-incision ......Conclusions based on meta-analyses of randomized trials carry a status of "truth." Methodological components may identify trials with systematic errors ("bias"). Trial sequential analysis (TSA) evaluates random errors in meta-analysis. We analyzed meta-analyses on laparoscopic vs. small...

  14. Probiotics for Preventing Ventilator-Associated Pneumonia in Mechanically Ventilated Patients: A Meta-Analysis with Trial Sequential Analysis

    Directory of Open Access Journals (Sweden)

    Hong Weng

    2017-10-01

    Full Text Available Background and Objective: Ventilator-associated pneumonia (VAP is still an important cause of morbidity and mortality in mechanically ventilated patients. The efficacy of the probiotics for preventing VAP is still controversial. Present study was conducted to comprehensively evaluate the effect of probiotics on VAP prevention in mechanically ventilated patients.Methods: PubMed, Embase, and CENTRAL were searched up to September 2016. Eligible trials designed with randomized controlled trials (RCTs comparing probiotics with control in mechanically ventilated patients were included. Risk ratios (RRs and mean differences (MDs with 95% confidence intervals (CIs were estimated with fixed or random effects models. Trial sequential analysis (TSA was performed using TSA 0.9beta software.Results: Thirteen RCTs (N = 1969 were included. Overall, probiotics were associated with reduced incidence of VAP (RR = 0.73, 95% CI = 0.60–0.89; P = 0.002, which was confirmed by TSA (TSA adjusted 95% CI = 0.55–0.96. However, no significant difference was observed in 90-day mortality (RR = 1.00, 95% CI = 0.72–1.37; P = 0.99, overall mortality (RR = 0.84, 95% CI = 0.70–1.02; P = 0.09, 28-day mortality (RR = 1.06, 95% CI = 0.72–1.57; P = 0.99, intensive care unit (ICU mortality (RR = 0.97, 95% CI = 0.74–1.27; P = 0.82, hospital mortality (RR = 0.81, 95% CI = 0.65–1.02; P = 0.07, diarrhea (RR = 0.99, 95% CI = 0.83–1.19; P = 0.92, length of ICU stay (MD = −2.40 days, 95% CI = −6.75 to 1.95; P = 0.28, length of hospital stay (MD = −1.34 days, 95% CI = −6.21 to 3.54; P = 0.59, and duration of mechanical ventilation (MD = −3.32 days, 95% CI = −6.74 to 0.09; P = 0.06.Conclusions: In this meta-analysis, we found that probiotics could reduce the incidence of VAP in mechanically ventilated patients. It seems likely that probiotics provide clinical benefits for mechanically ventilated patients.

  15. Adjuvant chemotherapy with sequential or concurrent anthracycline and docetaxel: Breast International Group 02-98 randomized trial

    DEFF Research Database (Denmark)

    Francis, P.; Crown, J.; Di, Leo A.

    2008-01-01

    BACKGROUND: Docetaxel is more effective than doxorubicin for patients with advanced breast cancer. The Breast International Group 02-98 randomized trial tested the effect of incorporating docetaxel into anthracycline-based adjuvant chemotherapy and compared sequential vs concurrent administration...... of doxorubicin at 50 mg/m2 plus docetaxel at 75 mg/m2, followed by three cycles of CMF). The primary comparison evaluated the efficacy of including docetaxel regardless of schedule and was planned after 1215 disease-free survival (DFS) events (ie, relapse, second primary cancer, or death from any cause...

  16. Levofloxacin Sequential Therapy vs Levofloxacin Triple Therapy in the Second-Line Treatment of Helicobacter pylori: A Randomized Trial.

    Science.gov (United States)

    Liou, Jyh-Ming; Bair, Ming-Jong; Chen, Chieh-Chang; Lee, Yi-Chia; Chen, Mei-Jyh; Chen, Chien-Chuan; Tseng, Cheng-Hao; Fang, Yu-Jen; Lee, Ji-Yuh; Yang, Tsung-Hua; Luo, Jiing-Chyuan; Wu, Jeng-Yih; Chang, Wen-Hsiung; Chang, Chun-Chao; Chen, Chi-Yi; Chen, Po-Yueh; Shun, Chia-Tung; Hsu, Wen-Feng; Hung, Hsu-Wei; Lin, Jaw-Town; Chang, Chi-Yang; Wu, Ming-Shiang

    2016-03-01

    The efficacy of levofloxacin triple therapy has fallen below 80% in the second-line treatment of Helicobacter pylori (H. pylori). We aimed to assess whether the levofloxacin sequential therapy is more effective than levofloxacin triple therapy in the second-line treatment. This open-label, randomized, multicenter trial was conducted between 2012 and 2015. H. pylori-infected subjects who failed from clarithromycin-based regimens (N=600) were randomized (1:1) to receive levofloxacin sequential therapy (LS: lansoprazole and amoxicillin for the first 5 days, followed by lansoprazole, levofloxacin, and metronidazole for another 5 days) or levofloxacin triple therapy (LT: lansoprazole, amoxicillin, and levofloxacin for 10 days). Successful eradication was defined as negative (13)C-urea breath test at least 6 weeks after treatment. Our primary outcome was the eradication rate by intention-to-treat (ITT) and per-protocol (PP) analyses. Antibiotic resistance was determined by agar dilution test. The prevalence of clarithromycin, levofloxacin, and metronidazole resistance was 60, 17.6, and 36.9%, respectively. The eradication rates of LS and LT were 84.3% (253/300) and 75.3% (226/300), respectively, in the ITT analysis (P=0.006) and 86.3% (253/293) and 78.8% (223/283), respectively, in the PP analysis (P=0.021). The efficacies of both LS and LT were affected by levofloxacin resistance. The secondary resistance of levofloxacin was 66.7 and 73.9% after LS and LT, respectively. The efficacies of LS and LT were not affected by the CYP2C19 polymorphism. Levofloxacin sequential therapy was more effective than levofloxacin triple therapy, and it is recommended in the second-line treatment for H. pylori ( NCT01537055).

  17. Radial Access Reduces Mortality in Patients With Acute Coronary Syndromes: Results From an Updated Trial Sequential Analysis of Randomized Trials.

    Science.gov (United States)

    Andò, Giuseppe; Capodanno, Davide

    2016-04-11

    The authors sought to investigate whether the cumulative evidence coming from randomized studies has reached the necessary power to consider radial access as a bleeding avoidance strategy that reduces mortality and ischemic endpoints in patients with acute coronary syndromes (ACS). Studies in ACS patients have reached conflicting conclusions about the impact of radial access in improving ischemic outcomes in addition to the established bleeding benefit. English-language publications and abstracts of major cardiovascular meetings until October 2015 were scrutinized. Study quality, patient characteristics, procedural data, and outcomes were extracted. Data were pooled in random effects meta-analyses with classic and trial sequential techniques. Trial sequential analysis combines the a priori information size calculation needed to allow for clinically meaningful statistical inference with the adjustment of thresholds for which results are considered significant. Seventeen studies, encompassing data from 19,328 patients, were pooled. Radial access was found to reduce mortality (relative risk [RR]: 0.73; 95% confidence interval [CI]: 0.60 to 0.88; p = 0.001), major adverse cardiovascular events (RR: 0.86; 95% CI: 0.77 to 0.95; p = 0.005), and major bleeding (RR: 0.60; 95% CI: 0.48 to 0.76; p < 0.001). Multiple sensitivity analyses showed consistent results, and trial sequential analysis suggested firm evidence for a meaningful reduction in mortality with radial access. Radial access reduces mortality compared with femoral access in ACS patients undergoing invasive management. This benefit is paralleled by consistent reductions in major adverse cardiovascular events and major bleeding, supporting radial access as the default strategy for cardiac catheterization in patients with ACS. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  18. A Molecular Mechanism for Sequential Activation of a G Protein-Coupled Receptor

    DEFF Research Database (Denmark)

    Grundmann, Manuel; Tikhonova, Irina G; Hudson, Brian D

    2016-01-01

    Ligands targeting G protein-coupled receptors (GPCRs) are currently classified as either orthosteric, allosteric, or dualsteric/bitopic. Here, we introduce a new pharmacological concept for GPCR functional modulation: sequential receptor activation. A hallmark feature of this is a stepwise ligand...... and pharmacological perturbations along with computational methods, and propose a kinetic model applicable to the analysis of sequential receptor activation. We envision this form of dynamic agonism as a common principle of nature to spatiotemporally encode cellular information....

  19. A Sequential Fluid-mechanic Chemical-kinetic Model of Propane HCCI Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Aceves, S M; Flowers, D L; Martinez-Frias, J; Smith, J R; Westbrook, C; Pitz, W; Dibble, R; Wright, J F; Akinyemi, W C; Hessel, R P

    2000-11-29

    We have developed a methodology for predicting combustion and emissions in a Homogeneous Charge Compression Ignition (HCCI) Engine. This methodology combines a detailed fluid mechanics code with a detailed chemical kinetics code. Instead of directly linking the two codes, which would require an extremely long computational time, the methodology consists of first running the fluid mechanics code to obtain temperature profiles as a function of time. These temperature profiles are then used as input to a multi-zone chemical kinetics code. The advantage of this procedure is that a small number of zones (10) is enough to obtain accurate results. This procedure achieves the benefits of linking the fluid mechanics and the chemical kinetics codes with a great reduction in the computational effort, to a level that can be handled with current computers. The success of this procedure is in large part a consequence of the fact that for much of the compression stroke the chemistry is inactive and thus has little influence on fluid mechanics and heat transfer. Then, when chemistry is active, combustion is rather sudden, leaving little time for interaction between chemistry and fluid mixing and heat transfer. This sequential methodology has been capable of explaining the main characteristics of HCCI combustion that have been observed in experiments. In this paper, we use our model to explore an HCCI engine running on propane. The paper compares experimental and numerical pressure traces, heat release rates, and hydrocarbon and carbon monoxide emissions. The results show an excellent agreement, even in parameters that are difficult to predict, such as chemical heat release rates. Carbon monoxide emissions are reasonably well predicted, even though it is intrinsically difficult to make good predictions of CO emissions in HCCI engines. The paper includes a sensitivity study on the effect of the heat transfer correlation on the results of the analysis. Importantly, the paper also

  20. Sequential sampling model for multiattribute choice alternatives with random attention time and processing order.

    Science.gov (United States)

    Diederich, Adele; Oswald, Peter

    2014-01-01

    A sequential sampling model for multiattribute binary choice options, called multiattribute attention switching (MAAS) model, assumes a separate sampling process for each attribute. During the deliberation process attention switches from one attribute consideration to the next. The order in which attributes are considered as well for how long each attribute is considered-the attention time-influences the predicted choice probabilities and choice response times. Several probability distributions for the attention time with different variances are investigated. Depending on the time and order schedule the model predicts a rich choice probability/choice response time pattern including preference reversals and fast errors. Furthermore, the difference between finite and infinite decision horizons for the attribute considered last is investigated. For the former case the model predicts a probability p 0 > 0 of not deciding within the available time. The underlying stochastic process for each attribute is an Ornstein-Uhlenbeck process approximated by a discrete birth-death process. All predictions are also true for the widely applied Wiener process.

  1. Sequential sampling model for multiattribute choice alternatives with random attention time and processing order

    Directory of Open Access Journals (Sweden)

    Adele eDiederich

    2014-09-01

    Full Text Available A sequential sampling model for multiattribute binary choice options, called Multiattribute attention switching (MAAS model, assumes a separate sampling process for each attribute. During the deliberation process attention switches from one attribute consideration to the next. The order in which attributes are considered as well for how long each attribute is considered - the attention time - influences the predicted choice probabilities and choice response times. Several probability distributions for the attention time including deterministic, Poisson, binomial, geometric, and uniform with different variances are investigated. Depending on the time and order schedule the model predicts a rich choice probability/choice response time pattern including preference reversals and fast errors. Furthermore, the difference between a finite and infinite decision horizons for the attribute considered last is investigated. For the former case the model predicts a probability $p_0> 0$ of not deciding within the available time. The underlying stochastic process for each attribute is an Ornstein-Uhlenbeck process approximated by a discrete birth-death process. All predictions are also true for the widely applied Wiener process.

  2. Customized Sequential Designs for Random Simulation Experiments : Kriging Metamodelling and Bootstrapping

    NARCIS (Netherlands)

    van Beers, W.C.M.; Kleijnen, J.P.C.

    2004-01-01

    This paper proposes a novel method to select an experimental design for interpolation in random simulation.(Though the paper focuses on Kriging, this method may also apply to other types of metamodels such as linear regression models.)Assuming that simulation requires much computer time, it is

  3. Customized Sequential Designs for Random Simulation Experiments : Kriging Metamodelling and Bootstrapping

    NARCIS (Netherlands)

    van Beers, W.C.M.; Kleijnen, J.P.C.

    2005-01-01

    This paper proposes a novel method to select an experimental design for interpolation in random simulation, especially discrete event simulation.(Though the paper focuses on Kriging, this design approach may also apply to other types of metamodels such as linear regression models.)Assuming that

  4. Customized sequential designs for random simulation experiments: Kriging metamodeling and bootstrapping

    NARCIS (Netherlands)

    Beers, van W.C.M.; Kleijnen, J.P.C.

    2005-01-01

    This paper proposes a novel method to select an experimental design for interpolation in random simulation, especially discrete event simulation. (Though the paper focuses on Kriging, this design approach may also apply to other types of metamodels such as linear regression models.) Assuming that

  5. Encoding Sequential Information in Vector Space Models of Semantics: Comparing Holographic Reduced Representation and Random Permutation

    OpenAIRE

    Recchia, Gabriel; Jones, Michael; Sahlgren, Magnus; Kanerva, Pentti

    2010-01-01

    Encoding information about the order in which words typically appear has been shown to improve the performance of high-dimensional semantic space models. This requires an encoding operation capable of binding together vectors in an order-sensitive way, and efficient enough to scale to large text corpora. Although both circular convolution and random permutations have been enlisted for this purpose in semantic models, these operations have never been systematically compared. In Experiment 1 we...

  6. TCP Traffic Control Evaluation and Reduction over Wireless Networks Using Parallel Sequential Decoding Mechanism

    Directory of Open Access Journals (Sweden)

    Ramazan Aygün

    2007-11-01

    Full Text Available The assumption of TCP-based protocols that packet error (lost or damaged is due to network congestion is not true for wireless networks. For wireless networks, it is important to reduce the number of retransmissions to improve the effectiveness of TCP-based protocols. In this paper, we consider improvement at the data link layer for systems that use stop-and-wait ARQ as in IEEE 802.11 standard. We show that increasing the buffer size will not solve the actual problem and moreover it is likely to degrade the quality of delivery (QoD. We firstly study a wireless router system model with a sequential convolutional decoder for error detection and correction in order to investigate QoD of flow and error control. To overcome the problems along with high packet error rate, we propose a wireless router system with parallel sequential decoders. We simulate our systems and provide performance in terms of average buffer occupancy, blocking probability, probability of decoding failure, system throughput, and channel throughput. We have studied these performance metrics for different channel conditions, packet arrival rates, decoding time-out limits, system capacities, and the number of sequential decoders. Our results show that parallel sequential decoders have great impact on the system performance and increase QoD significantly.

  7. TCP Traffic Control Evaluation and Reduction over Wireless Networks Using Parallel Sequential Decoding Mechanism

    Directory of Open Access Journals (Sweden)

    Aygün Ramazan

    2007-01-01

    Full Text Available The assumption of TCP-based protocols that packet error (lost or damaged is due to network congestion is not true for wireless networks. For wireless networks, it is important to reduce the number of retransmissions to improve the effectiveness of TCP-based protocols. In this paper, we consider improvement at the data link layer for systems that use stop-and-wait ARQ as in IEEE 802.11 standard. We show that increasing the buffer size will not solve the actual problem and moreover it is likely to degrade the quality of delivery (QoD. We firstly study a wireless router system model with a sequential convolutional decoder for error detection and correction in order to investigate QoD of flow and error control. To overcome the problems along with high packet error rate, we propose a wireless router system with parallel sequential decoders. We simulate our systems and provide performance in terms of average buffer occupancy, blocking probability, probability of decoding failure, system throughput, and channel throughput. We have studied these performance metrics for different channel conditions, packet arrival rates, decoding time-out limits, system capacities, and the number of sequential decoders. Our results show that parallel sequential decoders have great impact on the system performance and increase QoD significantly.

  8. Automated segmentation of dental CBCT image with prior-guided sequential random forests

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Li; Gao, Yaozong; Shi, Feng; Li, Gang [Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7513 (United States); Chen, Ken-Chung; Tang, Zhen [Surgical Planning Laboratory, Department of Oral and Maxillofacial Surgery, Houston Methodist Research Institute, Houston, Texas 77030 (United States); Xia, James J., E-mail: dgshen@med.unc.edu, E-mail: JXia@HoustonMethodist.org [Surgical Planning Laboratory, Department of Oral and Maxillofacial Surgery, Houston Methodist Research Institute, Houston, Texas 77030 (United States); Department of Surgery (Oral and Maxillofacial Surgery), Weill Medical College, Cornell University, New York, New York 10065 (United States); Department of Oral and Craniomaxillofacial Surgery, Shanghai Jiao Tong University School of Medicine, Shanghai Ninth People’s Hospital, Shanghai 200011 (China); Shen, Dinggang, E-mail: dgshen@med.unc.edu, E-mail: JXia@HoustonMethodist.org [Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7513 and Department of Brain and Cognitive Engineering, Korea University, Seoul 02841 (Korea, Republic of)

    2016-01-15

    Purpose: Cone-beam computed tomography (CBCT) is an increasingly utilized imaging modality for the diagnosis and treatment planning of the patients with craniomaxillofacial (CMF) deformities. Accurate segmentation of CBCT image is an essential step to generate 3D models for the diagnosis and treatment planning of the patients with CMF deformities. However, due to the image artifacts caused by beam hardening, imaging noise, inhomogeneity, truncation, and maximal intercuspation, it is difficult to segment the CBCT. Methods: In this paper, the authors present a new automatic segmentation method to address these problems. Specifically, the authors first employ a majority voting method to estimate the initial segmentation probability maps of both mandible and maxilla based on multiple aligned expert-segmented CBCT images. These probability maps provide an important prior guidance for CBCT segmentation. The authors then extract both the appearance features from CBCTs and the context features from the initial probability maps to train the first-layer of random forest classifier that can select discriminative features for segmentation. Based on the first-layer of trained classifier, the probability maps are updated, which will be employed to further train the next layer of random forest classifier. By iteratively training the subsequent random forest classifier using both the original CBCT features and the updated segmentation probability maps, a sequence of classifiers can be derived for accurate segmentation of CBCT images. Results: Segmentation results on CBCTs of 30 subjects were both quantitatively and qualitatively validated based on manually labeled ground truth. The average Dice ratios of mandible and maxilla by the authors’ method were 0.94 and 0.91, respectively, which are significantly better than the state-of-the-art method based on sparse representation (p-value < 0.001). Conclusions: The authors have developed and validated a novel fully automated method

  9. Cumulative Hazard Ratio Estimation for Treatment Regimes in Sequentially Randomized Clinical Trials.

    Science.gov (United States)

    Tang, Xinyu; Wahed, Abdus S

    2015-05-01

    The proportional hazards model is widely used in survival analysis to allow adjustment for baseline covariates. The proportional hazard assumption may not be valid for treatment regimes that depend on intermediate responses to prior treatments received, and it is not clear how such a model can be adapted to clinical trials employing more than one randomization. Besides, since treatment is modified post-baseline, the hazards are unlikely to be proportional across treatment regimes. Although Lokhnygina and Helterbrand (Biometrics 63: 422-428, 2007) introduced the Cox regression method for two-stage randomization designs, their method can only be applied to test the equality of two treatment regimes that share the same maintenance therapy. Moreover, their method does not allow auxiliary variables to be included in the model nor does it account for treatment effects that are not constant over time. In this article, we propose a model that assumes proportionality across covariates within each treatment regime but not across treatment regimes. Comparisons among treatment regimes are performed by testing the log ratio of the estimated cumulative hazards. The ratio of the cumulative hazard across treatment regimes is estimated using a weighted Breslow-type statistic. A simulation study was conducted to evaluate the performance of the estimators and proposed tests.

  10. Spatial distribution of sequential ventilation during mechanical ventilation of the uninjured lung: an argument for cyclical airway collapse and expansion

    Directory of Open Access Journals (Sweden)

    Altemeier William A

    2010-05-01

    Full Text Available Abstract Background Ventilator-induced lung injury (VILI is a recognized complication of mechanical ventilation. Although the specific mechanism by which mechanical ventilation causes lung injury remains an active area of study, the application of positive end expiratory pressure (PEEP reduces its severity. We have previously reported that VILI is spatially heterogeneous with the most severe injury in the dorsal-caudal lung. This regional injury heterogeneity was abolished by the application of PEEP = 8 cm H2O. We hypothesized that the spatial distribution of lung injury correlates with areas in which cyclical airway collapse and recruitment occurs. Methods To test this hypothesis, rabbits were mechanically ventilated in the supine posture, and regional ventilation distribution was measured under four conditions: tidal volumes (VT of 6 and 12 ml/kg with PEEP levels of 0 and 8 cm H2O. Results We found that relative ventilation was sequentially redistributed towards dorsal-caudal lung with increasing tidal volume. This sequential ventilation redistribution was abolished with the addition of PEEP. Conclusions These results suggest that cyclical airway collapse and recruitment is regionally heterogeneous and spatially correlated with areas most susceptible to VILI.

  11. Communication interventions for minimally verbal children with autism: a sequential multiple assignment randomized trial.

    Science.gov (United States)

    Kasari, Connie; Kaiser, Ann; Goods, Kelly; Nietfeld, Jennifer; Mathy, Pamela; Landa, Rebecca; Murphy, Susan; Almirall, Daniel

    2014-06-01

    This study tested the effect of beginning treatment with a speech-generating device (SGD) in the context of a blended, adaptive treatment design for improving spontaneous, communicative utterances in school-aged, minimally verbal children with autism. A total of 61 minimally verbal children with autism, aged 5 to 8 years, were randomized to a blended developmental/behavioral intervention (JASP+EMT) with or without the augmentation of a SGD for 6 months with a 3-month follow-up. The intervention consisted of 2 stages. In stage 1, all children received 2 sessions per week for 3 months. Stage 2 intervention was adapted (by increased sessions or adding the SGD) based on the child's early response. The primary outcome was the total number of spontaneous communicative utterances; secondary measures were the total number of novel words and total comments from a natural language sample. Primary aim results found improvements in spontaneous communicative utterances, novel words, and comments that all favored the blended behavioral intervention that began by including an SGD (JASP+EMT+SGD) as opposed to spoken words alone (JASP+EMT). Secondary aim results suggest that the adaptive intervention beginning with JASP+EMT+SGD and intensifying JASP+EMT+SGD for children who were slow responders led to better posttreatment outcomes. Minimally verbal school-aged children can make significant and rapid gains in spoken spontaneous language with a novel, blended intervention that focuses on joint engagement and play skills and incorporates an SGD. Future studies should further explore the tailoring design used in this study to better understand children's response to treatment. Clinical trial registration information-Developmental and Augmented Intervention for Facilitating Expressive Language (CCNIA); http://clinicaltrials.gov/; NCT01013545. Copyright © 2014 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

  12. Communication Interventions for Minimally Verbal Children With Autism: Sequential Multiple Assignment Randomized Trial

    Science.gov (United States)

    Kasari, Connie; Kaiser, Ann; Goods, Kelly; Nietfeld, Jennifer; Mathy, Pamela; Landa, Rebecca; Murphy, Susan; Almirall, Daniel

    2014-01-01

    Objective This study tested the effect of beginning treatment with a speech-generating device in the context of a blended, adaptive treatment design for improving spontaneous, communicative utterances in school-aged, minimally verbal children with autism. Method Sixty-one minimally verbal children with autism, aged 5 to 8 years, were randomized to a blended developmental/behavioral intervention (JASP+EMT) with or without the augmentation of a speech-generating device (SGD) for 6 months with a 3-month follow-up. The intervention consisted of two stages. In Stage 1 all children received two sessions per week for 3 months. Stage 2 intervention was adapted (increased sessions or adding the SGD) based on the child’s early response. The primary outcome was the total number of spontaneous communicative utterances; secondary measures were total number of novel words and total comments from a natural language sample. Results Primary aim results found improvements in spontaneous communicative utterances, novel words, and comments that all favored the blended behavioral intervention that began by including an SGD (JASP+EMT+SGD) as opposed to spoken words alone (JASP+EMT). Secondary aim results suggest that the adaptive intervention beginning with JASP+EMT+SGD and intensifying JASP+EMT+SGD for children who were slow responders led to better post-treatment outcomes. Conclusion Minimally verbal school-aged children can make significant and rapid gains in spoken spontaneous language with a novel, blended intervention that focuses on joint engagement and play skills and incorporates an SGD. Future studies should further explore the tailoring design used in this study to better understand children’s response to treatment. Clinical trial registration information—Developmental and Augmented Intervention for Facilitating Expressive Language (CCNIA); http://clinicaltrials.gov/; NCT01013545. PMID:24839882

  13. "Buy-It-Now" or "Sell-It-Now" Auctions: Effects of Changing Bargaining Power in Sequential Trading Mechanisms

    OpenAIRE

    Grebe, Tim; Ivanova-Stenzel, Radosveta; Kröger, Sabine

    2015-01-01

    We study experimentally the effect of bargaining power in two sequential mechanisms that offer the possibility to trade at a fixed price before an auction. In the “Buy-It-Now” format, the seller has the bargaining power and offers a price prior to the auction; whereas in the “Sell-It-Now” format, it is the buyer. Both formats are extensively used in online and offline markets. Despite very different strategic implications for buyers and sellers, results from our experiment suggest...

  14. Cupping therapy versus acupuncture for pain-related conditions: a systematic review of randomized controlled trials and trial sequential analysis.

    Science.gov (United States)

    Zhang, Ya-Jing; Cao, Hui-Juan; Li, Xin-Lin; Yang, Xiao-Ying; Lai, Bao-Yong; Yang, Guo-Yang; Liu, Jian-Ping

    2017-01-01

    Both cupping therapy and acupuncture have been used in China for a long time, and their target indications are pain-related conditions. There is no systematic review comparing the effectiveness of these two therapies. To compare the beneficial effectiveness and safety between cupping therapy and acupuncture for pain-related conditions to provide evidence for clinical practice. Protocol of this review was registered in PROSPERO (CRD42016050986). We conducted literature search from six electronic databases until 31st March 2017. We included randomized trials comparing cupping therapy with acupuncture on pain-related conditions. Methodological quality of the included studies was evaluated by risk of bias tool. Mean difference, risk ratio, risk difference and their 95% confidence interval were used to report the estimate effect of the pooled results through meta-analysis or the results from each individual study. Trial sequential analysis (TSA) was applied to adjust random errors and calculate the sample size. Twenty-three randomized trials with 2845 participants were included covering 12 pain-related conditions. All included studies were of poor methodological quality. Three meta-analyses were conducted, which showed similar clinical beneficial effects of cupping therapy and acupuncture for the rate of symptom improvement in cervical spondylosis (RR 1.13, 95% CI 1.01 to 1.26; n = 646), lateral femoral cutaneous neuritis (RR 1.10, 95% CI 1.00 to 1.22; n = 102) and scapulohumeral periarthritis (RR 1.31, 95% CI 1.15 to 1.51; n = 208). Results from other outcomes (such as visual analogue and numerical rating scale) in each study also showed no statistical significant difference between these two therapies for all included pain-related conditions. The results of TSA for cervical spondylosis demonstrated that the current available data have not reached a powerful conclusion. No serious adverse events related to cupping therapy or acupuncture was found in included

  15. Sequential psychological and pharmacological therapies for comorbid and primary insomnia: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Morin, Charles M; Edinger, Jack D; Krystal, Andrew D; Buysse, Daniel J; Beaulieu-Bonneau, Simon; Ivers, Hans

    2016-03-03

    Chronic insomnia is a prevalent disorder associated with significant psychosocial, health, and economic impacts. Cognitive behavioral therapies (CBTs) and benzodiazepine receptor agonist (BzRA) medications are the most widely supported therapeutic approaches for insomnia management. However, few investigations have directly compared their relative and combined benefits, and even fewer have tested the benefits of sequential treatment for those who do not respond to initial insomnia therapy. Moreover, insomnia treatment studies have been limited by small, highly screened study samples, fixed-dose, and fixed-agent pharmacotherapy strategies that do not represent usual clinical practices. This study will address these limitations. This is a two-site randomized controlled trial, which will enroll 224 adults who meet the criteria for a chronic insomnia disorder with or without comorbid psychiatric disorders. Prospective participants will complete clinical assessments and polysomnography and then will be randomly assigned to first-stage therapy involving either behavioral therapy (BT) or zolpidem. Treatment outcomes will be assessed after 6 weeks, and treatment remitters will be followed for the next 12 months on maintenance therapy. Those not achieving remission will be offered randomization to a second, 6-week treatment, again involving either pharmacotherapy (zolpidem or trazodone) or psychological therapy (BT or cognitive therapy (CT)). All participants will be re-evaluated 12 weeks after the protocol initiation and at 3-, 6-, 9-, and 12-month follow-ups. Insomnia remission, defined categorically as a score Insomnia Severity Index, a patient-reported outcome, will serve as the primary endpoint for treatment comparisons. Secondary outcomes will include sleep parameters derived from daily sleep diaries and from polysomnography, subjective measures of fatigue, mood, quality of life, and functional impairments; and measures of adverse events; dropout rates; and treatment

  16. Reconsidering Sequential Double Running Suture Removal After Penetrating Keratoplasty: A Prospective Randomized Study Comparing Excimer Laser and Motor Trephination.

    Science.gov (United States)

    Seitz, Berthold; Hager, Tobias; Langenbucher, Achim; Naumann, Gottfried O H

    2017-12-14

    We assessed the impact of sequential double running suture removal on corneal curvature after penetrating keratoplasty (PK), comparing mechanical and nonmechanical excimer laser trephination. PK was performed in 134 patients (mean age 51 ± 18 yrs) using either the excimer laser [excimer, n = 60 (37 keratoconus and 23 Fuchs dystrophy)] or motor trephination [control, n = 74 (44 keratoconus and 30 Fuchs dystrophy)] and a double running cross-stitch suture. Refractometry, Zeiss keratometry, and Tomey corneal topography were performed before removal of the first suture (15.2 ± 4.2 mo) and immediately before and at least 6 weeks after removal of the second suture (21.4 ± 5.6 mo). Keratometry before removal of the first (-1.7 ± 2.3 D vs. -3.1 ± 2.8 D) and second (-2.3 ± 2.6 D vs. -3.8 ± 2.8 D) sutures showed that the change in the corneal base curve was significantly smaller in the excimer group than the control group (P control groups, respectively, resulting in significantly lower astigmatism in the excimer (3.1 ± 2.1 D) group compared with the control group (6.2 ± 2.9 D) with "all-sutures-out" (P vector-corrected astigmatism (Jaffe) was significantly smaller in the excimer group (4.3 ± 3.5 D) than in the control group (6.9 ± 4.5 D; P motor trephination.

  17. Mechanical Behavior of Homogeneous and Composite Random Fiber Networks

    Science.gov (United States)

    Shahsavari, Ali

    systems with large multiscale heterogeneity, which controls their mechanical behavior. This pronounced heterogeneity leads to a pronounced size and boundary condition effects on their mechanical behavior. To emphasize the source of the size effect, the network heterogeneity is characterized by analyzing the geometry of the network (density distribution), the strain field and the strain energy distribution. It is shown that the heterogeneity of the mechanical fields depends not only on the network topology, but also on the ratio between the bending and axial stiffness of fibers. In this study, the size effect is quantified and the minimum model size needed to eliminate the size effect for a given set of system parameters, is determined. The results are also used for the selection of the size of representative volume elements useful for multiscale models of fiber networks such as the sequential approach. The elastic response of composite random fiber networks in which two types of fibers are used, is studied. This analysis is performed by adding stiff fibers to a relatively softer base while considering two cases: cross-linked and non-cross-linked added fibers. The linear elastic modulus of the network is determined in terms of the system parameters, including the density of added fibers. The results are compared to the case of adding stiff fibers to a homogeneous continuum base. It is shown that there is a threshold of added fiber density, above which the axial stiffens of the base filaments controls the mechanics. In this regime, the elastic response of the composites that have network bases mimics the behavior of those with continuum bases. The results presented in this thesis are relevant for many biological and engineering fibrous materials, including connective tissue, the cellular cytoskeleton, special clothing, consumer products, filters, and dampers. It is shown that the overall behavior of the material is very sensitive to several system parameters (power law

  18. BspRI restriction endonuclease: cloning, expression in Escherichia coli and sequential cleavage mechanism.

    Science.gov (United States)

    Raskó, Tamás; Dér, András; Klement, Eva; Slaska-Kiss, Krystyna; Pósfai, Eszter; Medzihradszky, Katalin F; Marshak, Daniel R; Roberts, Richard J; Kiss, Antal

    2010-11-01

    The GGCC-specific restriction endonuclease BspRI is one of the few Type IIP restriction endonucleases, which were suggested to be a monomer. Amino acid sequence information obtained by Edman sequencing and mass spectrometry analysis was used to clone the gene encoding BspRI. The bspRIR gene is located adjacently to the gene of the cognate modification methyltransferase and encodes a 304 aa protein. Expression of the bspRIR gene in Escherichia coli was dependent on the replacement of the native TTG initiation codon with an ATG codon, explaining previous failures in cloning the gene using functional selection. A plasmid containing a single BspRI recognition site was used to analyze kinetically nicking and second-strand cleavage under steady-state conditions. Cleavage of the supercoiled plasmid went through a relaxed intermediate indicating sequential hydrolysis of the two strands. Results of the kinetic analysis of the first- and second-strand cleavage are consistent with cutting the double-stranded substrate site in two independent binding events. A database search identified eight putative restriction-modification systems in which the predicted endonucleases as well as the methyltransferases share high sequence similarity with the corresponding protein of the BspRI system. BspRI and the related putative restriction endonucleases belong to the PD-(D/E)XK nuclease superfamily.

  19. Sequential alternating deferiprone and deferoxamine treatment compared to deferiprone monotherapy: main findings and clinical follow-up of a large multicenter randomized clinical trial in -thalassemia major patients

    DEFF Research Database (Denmark)

    Pantalone, Gaetano Restivo; Maggio, Aurelio; Vitrano, Angela

    2011-01-01

    In β-thalassemia major (β-TM) patients, iron chelation therapy is mandatory to reduce iron overload secondary to transfusions. Recommended first line treatment is deferoxamine (DFO) from the age of 2 and second line treatment after the age of 6 is deferiprone (L1). A multicenter randomized open...... thalassemia patients were randomized and underwent intention-to-treat analysis. Statistically, a decrease of serum ferritin level was significantly higher in alternating sequential L1-DFO patients compared with L1 alone patients (p = 0.005). Kaplan-Meier survival analysis for the two chelation treatments did...

  20. Noninferiority, randomized, controlled trial comparing embryo development using media developed for sequential or undisturbed culture in a time-lapse setup.

    Science.gov (United States)

    Hardarson, Thorir; Bungum, Mona; Conaghan, Joe; Meintjes, Marius; Chantilis, Samuel J; Molnar, Laszlo; Gunnarsson, Kristina; Wikland, Matts

    2015-12-01

    To study whether a culture medium that allows undisturbed culture supports human embryo development to the blastocyst stage equivalently to a well-established sequential media. Randomized, double-blinded sibling trial. Independent in vitro fertilization (IVF) clinics. One hundred twenty-eight patients, with 1,356 zygotes randomized into two study arms. Embryos randomly allocated into two study arms to compare embryo development on a time-lapse system using a single-step medium or sequential media. Percentage of good-quality blastocysts on day 5. Percentage of day 5 good-quality blastocysts was 21.1% (standard deviation [SD] ± 21.6%) and 22.2% (SD ± 22.1%) in the single-step time-lapse medium (G-TL) and the sequential media (G-1/G-2) groups, respectively. The mean difference (-1.2; 95% CI, -6.0; 3.6) between the two media systems for the primary end point was less than the noninferiority margin of -8%. There was a statistically significantly lower number of good-quality embryos on day 3 in the G-TL group [50.7% (SD ± 30.6%) vs. 60.8% (SD ± 30.7%)]. Four out of the 11 measured morphokinetic parameters were statistically significantly different for the two media used. The mean levels of ammonium concentration in the media at the end of the culture period was statistically significantly lower in the G-TL group as compared with the G-2 group. We have shown that a single-step culture medium supports blastocyst development equivalently to established sequential media. The ammonium concentrations were lower in the single-step media, and the measured morphokinetic parameters were modified somewhat. NCT01939626. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  1. Concurrent versus Sequential Chemoradiotherapy with Cisplatin and Vinorelbine in Locally Advanced Non-Small Cell Lung Cancer: A Randomized Study

    Czech Academy of Sciences Publication Activity Database

    Zatloukal, P.; Petruželka, L.; Zemanová, M.; Havel, L.; Janků, F.; Judas, L.; Kubík, A.; Křepela, E.; Fiala, P.; Pecen, Ladislav

    2004-01-01

    Roč. 46, - (2004), s. 87-98 ISSN 0169-5002 Institutional research plan: CEZ:AV0Z1030915 Keywords : concurrent chemoradiotherapy * sequential chemoradiotherapy * locally advanced non-small cell lung cancer * cisplatin * vinorelbine Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 2.914, year: 2004

  2. Sequential stamen maturation and movement in a protandrous herb: mechanisms increasing pollination efficiency and reducing sexual interference.

    Science.gov (United States)

    Xiao, Chang-Long; Deng, Hui; Xiang, Gan-Ju; Luguba, Kadiori Edwin; Guo, You-Hao; Yang, Chun-Feng

    2017-05-01

    Successive stamen movement directly controls pollen presentation schedules through sequential stamen maturation and changes the extent of herkogamy by altering the positions of sexual organs. However, the implications of such movements in terms of pollination are not well understood. Pollen presentation theory predicts that staggered pollen presentation should be favoured when plants are subject to diminishing returns on pollen transfer. Herkogamy on the other hand, has been interpreted as an adaptive trait that reduces sexual interference in hermaphrodite flowers. In this study, we conducted floral manipulations to determine the function of successive stamen movement in pollen transfer. By artificially manipulating the flowers to present two anthers simultaneously in the floral centre, we attempted to investigate whether changes in the anther presentation strategy affect pollen removal, deposition and the efficiency of pollinators. Compared with the natural treatment, the pollen transfer efficiency of halictid bees decreased significantly when the flowers were manipulated to present two anthers simultaneously. Although the presentation of two anthers simultaneously led to a similar pollen removal rate, there was a significant reduction in pollen deposition on neighbouring stigmas. To evaluate the effect of movement herkogamy on pollen export and deposition and seed set, the flowers were manipulated with or without the movement of stamen bending out from the floral centre. Pollen export decreased significantly when the central anther was moved away from the pistil, and pollen deposition and seed set declined significantly when the five spent anthers were retained on the pistil. Our study provides good support for the pollen presentation theory and provides direct experimental evidence that successive stamen movement could increase pollen transfer efficiency by sequential stamen maturation. Moreover, movement herkogamy promotes pollen export, deposition and seed set

  3. Blastocyst culture using single versus sequential media in clinical IVF: a systematic review and meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Sfontouris, Ioannis A; Martins, Wellington P; Nastri, Carolina O; Viana, Iara G R; Navarro, Paula A; Raine-Fenning, Nick; van der Poel, Sheryl; Rienzi, Laura; Racowsky, Catherine

    2016-10-01

    The purpose of this study was to undertake a review of the available evidence comparing the use of a single medium versus sequential media for embryo culture to the blastocyst stage in clinical IVF. We searched the Cochrane Central, PubMed, Scopus, ClinicalTrials.gov, Current Controlled Trials and WHO International Clinical Trials Registry Platform to identify randomized controlled trials comparing single versus sequential media for blastocyst culture and ongoing pregnancy rate. Included studies randomized either oocytes/zygotes or women. Eligible oocyte/zygote studies were analyzed to assess the risk difference (RD) and 95 % confidence intervals (CI) between the two media systems; eligible woman-based studies were analyzed to assess the risk ratio (RR) and 95 % CI for clinical pregnancy rate. No differences were observed between single and sequential media for either ongoing pregnancy per randomized woman (relative risk (RR) = 0.9, 95 % CI = 0.7 to 1.3, two studies including 246 women, I 2  = 0 %) or clinical pregnancy per randomized woman (RR = 1.0, 95 % CI = 0.7 to 1.4, one study including 100 women); or miscarriage per clinical pregnancy: RR = 1.3, 95 % CI = 0.4 to 4.3, two studies including 246 participants, I 2  = 0 %). Single media use was associated with an increase blastocyst formation per randomized oocyte/zygote (relative distribution (RD) = +0.06, 95 % CI = +0.01 to +0.12, ten studies including 7455 oocytes/zygotes, I 2  = 83 %) but not top/high blastocyst formation (RD = +0.05, 95 % CI = -0.01 to +0.11, five studies including 3879 oocytes/zygotes, I 2  = 93 %). The overall quality of the evidence was very low for all these four outcomes. Although using a single medium for extended culture has some practical advantages and blastocyst formation rates appear to be higher, there is insufficient evidence to recommend either sequential or single-step media as being superior for the culture of

  4. Multidimensional treatment of stochastic solvent dynamics in photoinduced proton-coupled electron transfer processes: sequential, concerted, and complex branching mechanisms.

    Science.gov (United States)

    Soudackov, Alexander V; Hazra, Anirban; Hammes-Schiffer, Sharon

    2011-10-14

    A theoretical approach for the multidimensional treatment of photoinduced proton-coupled electron transfer (PCET) processes in solution is presented. This methodology is based on the multistate continuum theory with an arbitrary number of diabatic electronic states representing the relevant charge distributions in a general PCET system. The active electrons and transferring proton(s) are treated quantum mechanically, and the electron-proton vibronic free energy surfaces are represented as functions of multiple scalar solvent coordinates corresponding to the single electron and proton transfer reactions involved in the PCET process. A dynamical formulation of the dielectric continuum theory is used to derive a set of coupled generalized Langevin equations of motion describing the time evolution of these collective solvent coordinates. The parameters in the Langevin equations depend on the solvent properties, such as the dielectric constants, relaxation time, and molecular moment of inertia, as well as the solute properties. The dynamics of selected intramolecular nuclear coordinates, such as the proton donor-acceptor distance or a torsional angle within the PCET complex, may also be included in this formulation. A surface hopping method in conjunction with the Langevin equations of motion is used to simulate the nonadiabatic dynamics on the multidimensional electron-proton vibronic free energy surfaces following photoexcitation. This theoretical treatment enables the description of both sequential and concerted mechanisms, as well as more complex processes involving a combination of these mechanisms. The application of this methodology to a series of model systems corresponding to collinear and orthogonal PCET illustrates fundamental aspects of these different mechanisms and elucidates the significance of proton vibrational relaxation and nonequilibrium solvent dynamics. © 2011 American Institute of Physics

  5. Randomized Controlled Trial for Helicobacter pylori Eradication in a Naive Portuguese Population: Is Sequential Treatment Superior to Triple Therapy in Real World Clinical Setting?

    Science.gov (United States)

    Boal Carvalho, Pedro; Magalhães, Joana; Dias de Castro, Francisca; Rosa, Bruno; Cotter, José

    2017-03-31

    Helicobacter pylori eradication has become increasingly difficult as resistances to several antibiotics develop. We aimed to compare Helicobacter pylori eradication rates between triple therapy and sequential therapy in a naive Portuguese population. Prospective randomized trial including consecutive patients referred for first-line Helicobacter pylori eradication treatment. previous gastric surgery/neoplasia, pregnancy/lactancy, allergy to any of the drugs. The compared eradication regimens were triple therapy (pantoprazol, amoxicillin and clarithromycin 12/12 hours, 14 days) and sequential therapy (pantoprazol 12/12 hours for 10 days, amoxicillin 12/12 hours for days 1 - 5 and clarithromycin plus metronidazol 12/12 hours during days 6 - 10). Eradication success was confirmed with urea breath test. Statistical analysis was performed with SPSS v21.0 and a p-value population, we found a satisfactory global Helicobacter pylori eradication rate of 82%, with no statistical differences observed in the efficacy of the treatment between triple and sequential regimens. These results support the use of either therapy for the first-line eradication of Helicobacter pylori.

  6. An Extension of a Parallel-Distributed Processing Framework of Reading Aloud in Japanese: Human Nonword Reading Accuracy Does Not Require a Sequential Mechanism

    Science.gov (United States)

    Ikeda, Kenji; Ueno, Taiji; Ito, Yuichi; Kitagami, Shinji; Kawaguchi, Jun

    2017-01-01

    Humans can pronounce a nonword (e.g., rint). Some researchers have interpreted this behavior as requiring a sequential mechanism by which a grapheme-phoneme correspondence rule is applied to each grapheme in turn. However, several parallel-distributed processing (PDP) models in English have simulated human nonword reading accuracy without a…

  7. Effects of Steroids on Quality of Recovery and Adverse Events after General Anesthesia: Meta-Analysis and Trial Sequential Analysis of Randomized Clinical Trials.

    Science.gov (United States)

    Mihara, Takahiro; Ishii, Tomoko; Ka, Koui; Goto, Takahisa

    2016-01-01

    Quality of recovery (QoR) after surgery is a relevant outcome. The early postoperative quality of recovery of a patient can be determined using the QoR-40 questionnaire. The aim of this meta-analysis and Trial Sequential Analysis was to determine if perioperative administration of glucocorticosteroids improved patients' quality of recovery after general anesthesia and if adverse events occurred. We searched six databases, including trial registration sites. Randomized clinical trials reporting the efficacy of glucocorticosteroids on quality of recovery evaluated using the QoR-40 after general anesthesia were eligible. The QoR-40 data were combined as the mean difference with confidence intervals using a random-effects model. The I2 statistic was used to assess heterogeneity. The quality of the trials was evaluated using the Cochrane methodology. Moreover, Trial Sequential Analysis was carried out to prevent the inflation of type 1 errors caused by multiple testing and sparse data. We also assessed adverse events. Three randomized clinical trials (totaling 301 patients) were analyzed. The results from one published and four unpublished randomized clinical trials were unavailable. Dexamethasone was investigated in all three trials, and the results suggested that it significantly improved QoR-40 at postoperative day one scores compared with placebo (mean difference [95% confidence interval]: 14.2 points [10.4 to 18.1]; P analysis because of the absence of trials with low risk of bias. The Trial Sequential Analysis-adjusted confidence interval was -1.6 to 30.0, indicating that further trials are required. The reporting of adverse events was insufficient. These findings indicate that perioperative dexamethasone administration may improve short-term (i.e., one day) quality of recovery after general anesthesia and surgery. We need more randomized clinical trials with low risk of bias assessing the effects of glucocorticosteroids on quality of life, other outcomes, and

  8. Random sampler M-estimator algorithm with sequential probability ratio test for robust function approximation via feed-forward neural networks.

    Science.gov (United States)

    El-Melegy, Moumen T

    2013-07-01

    This paper addresses the problem of fitting a functional model to data corrupted with outliers using a multilayered feed-forward neural network. Although it is of high importance in practical applications, this problem has not received careful attention from the neural network research community. One recent approach to solving this problem is to use a neural network training algorithm based on the random sample consensus (RANSAC) framework. This paper proposes a new algorithm that offers two enhancements over the original RANSAC algorithm. The first one improves the algorithm accuracy and robustness by employing an M-estimator cost function to decide on the best estimated model from the randomly selected samples. The other one improves the time performance of the algorithm by utilizing a statistical pretest based on Wald's sequential probability ratio test. The proposed algorithm is successfully evaluated on synthetic and real data, contaminated with varying degrees of outliers, and compared with existing neural network training algorithms.

  9. Apparently conclusive meta-analyses may be inconclusive--Trial sequential analysis adjustment of random error risk due to repetitive testing of accumulating data in apparently conclusive neonatal meta-analyses

    DEFF Research Database (Denmark)

    Brok, Jesper; Thorlund, Kristian; Wetterslev, Jørn

    2008-01-01

    BACKGROUND: Random error may cause misleading evidence in meta-analyses. The required number of participants in a meta-analysis (i.e. information size) should be at least as large as an adequately powered single trial. Trial sequential analysis (TSA) may reduce risk of random errors due...

  10. Sequential FOLFIRI.3 + Gemcitabine Improves Health-Related Quality of Life Deterioration-Free Survival of Patients with Metastatic Pancreatic Adenocarcinoma: A Randomized Phase II Trial.

    Directory of Open Access Journals (Sweden)

    Amélie Anota

    Full Text Available A randomized multicenter phase II trial was conducted to assess the sequential treatment strategy using FOLFIRI.3 and gemcitabine alternately (Arm 2 compared to gemcitabine alone (Arm 1 in patients with metastatic non pre-treated pancreatic adenocarcinoma. The primary endpoint was the progression-free survival (PFS rate at 6 months. It concludes that the sequential treatment strategy appears to be feasible and effective with a PFS rate of 43.5% in Arm 2 at 6 months (26.1% in Arm 1. This paper reports the results of the longitudinal analysis of the health-related quality of life (HRQoL as a secondary endpoint of this study.HRQoL was evaluated using the EORTC QLQ-C30 at baseline and every two months until the end of the study or death. HRQoL deterioration-free survival (QFS was defined as the time from randomization to a first significant deterioration as compared to the baseline score with no further significant improvement, or death. A propensity score was estimated comparing characteristics of partial and complete responders. Analyses were repeated with inverse probability weighting method using the propensity score. Multivariate Cox regression analyses were performed to identify independent factors influencing QFS.98 patients were included between 2007 and 2011. Adjusting on the propensity score, patients of Arm 2 presented a longer QFS of Global Health Status (Hazard Ratio: 0.52 [0.31-0.85], emotional functioning (0.35 [0.21-0.59] and pain (0.50 [0.31-0.81] than those of Arm 1.Patients of Arm 2 presented a better HRQoL with a longer QFS than those of Arm 1. Moreover, the propensity score method allows to take into account the missing data depending on patients' characteristics.Eudract N° 2006-005703-34. (Name of the Trial: FIRGEM.

  11. Acceptance and commitment therapy - Do we know enough? Cumulative and sequential meta-analyses of randomized controlled trials.

    Science.gov (United States)

    Hacker, Thomas; Stone, Paul; MacBeth, Angus

    2016-01-15

    Acceptance and Commitment Therapy (ACT) has accrued a substantial evidence base. Recent systematic and meta-analytic reviews suggest that ACT is effective compared to control conditions. However, these reviews appraise the efficacy of ACT across a broad range of presenting problems, rather than addressing specific common mental health difficulties. Focussing on depression and anxiety we performed a meta-analysis of trials of ACT. We incorporated sequential meta-analysis (SMA) techniques to critically appraise the sufficiency of the existing evidence base. Findings suggest that ACT demonstrates at least moderate group and pre-post effects for symptom reductions for both anxiety and depression. However using SMA findings are more qualified. There is currently insufficient evidence to confidently conclude that ACT for anxiety is efficacious when compared to active control conditions or as primary treatment for anxiety. Similarly, using SMA, there is currently insufficient evidence to suggest a moderate efficacy of ACT for depression compared to active control conditions. To stimulate further research we offer specific estimates of additional numbers of participants required to reach sufficiency to help inform future studies. We also discuss the appropriate strategies for future research into ACT for anxiety given the current evidence suggests no differential efficacy of ACT in the treatment of anxiety compared to active control conditions. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. The totally extraperitoneal method versus Lichtenstein's technique for inguinal hernia repair: a systematic review with meta-analyses and trial sequential analyses of randomized clinical trials.

    Directory of Open Access Journals (Sweden)

    G G Koning

    Full Text Available BACKGROUND: Lichtenstein's technique is considered the reference technique for inguinal hernia repair. Recent trials suggest that the totally extraperitoneal (TEP technique may lead to reduced proportions of chronic pain. A systematic review evaluating the benefits and harms of the TEP compared with Lichtenstein's technique is needed. METHODOLOGY/PRINCIPAL FINDINGS: The review was performed according to the 'Cochrane Handbook for Systematic Reviews'. Searches were conducted until January 2012. Patients with primary uni- or bilateral inguinal hernias were included. Only trials randomising patients to TEP and Lichtenstein were included. Bias evaluation and trial sequential analysis (TSA were performed. The error matrix was constructed to minimise the risk of systematic and random errors. Thirteen trials randomized 5404 patients. There was no significant effect of the TEP compared with the Lichtenstein on the number of patients with chronic pain in a random-effects model risk ratio (RR 0.80; 95% confidence interval (CI 0.61 to 1.04; p = 0.09. There was also no significant effect on number of patients with recurrences in a random-effects model (RR 1.41; 95% CI 0.72 to 2.78; p = 0.32 and the TEP technique may or may not be associated with less severe adverse events (random-effects model RR 0.91; 95% CI 0.73 to 1.12; p = 0.37. TSA showed that the required information size was far from being reached for patient important outcomes. CONCLUSIONS/SIGNIFICANCE: TEP versus Lichtenstein for inguinal hernia repair has been evaluated by 13 trials with high risk of bias. The review with meta-analyses, TSA and error matrix approach shows no conclusive evidence of a difference between TEP and Lichtenstein on the primary outcomes chronic pain, recurrences, and severe adverse events.

  13. Sequential analysis

    CERN Document Server

    Wald, Abraham

    2013-01-01

    In 1943, while in charge of Columbia University's Statistical Research Group, Abraham Wald devised Sequential Design, an innovative statistical inference system. Because the decision to terminate an experiment is not predetermined, sequential analysis can arrive at a decision much sooner and with substantially fewer observations than equally reliable test procedures based on a predetermined number of observations. The system's immense value was immediately recognized, and its use was restricted to wartime research and procedures. In 1945, it was released to the public and has since revolutio

  14. Advanced ovarian cancer: phase III randomized study of sequential cisplatin-topotecan and carboplatin-paclitaxel vs carboplatin-paclitaxel.

    Science.gov (United States)

    Hoskins, P; Vergote, I; Cervantes, A; Tu, D; Stuart, G; Zola, P; Poveda, A; Provencher, D; Katsaros, D; Ojeda, B; Ghatage, P; Grimshaw, R; Casado, A; Elit, L; Mendiola, C; Sugimoto, A; D'Hondt, V; Oza, A; Germa, J R; Roy, M; Brotto, L; Chen, D; Eisenhauer, E A

    2010-10-20

    Topotecan has single-agent activity in recurrent ovarian cancer. It was evaluated in a novel combination compared with standard frontline therapy. Women aged 75 years or younger with newly diagnosed stage IIB or greater ovarian cancer, Eastern Cooperative Oncology Group Performance Status of 1 or less, were stratified by type of primary surgery and residual disease, treatment center, and age; then randomly assigned to one of the two 21-day intravenous regimens. Patients in arm 1 (n = 409) were administered four cycles of cisplatin 50 mg/m(2) on day 1 and topotecan 0.75 mg/m(2) on days 1-5, then four cycles of paclitaxel 175 mg/m(2) over 3 hours on day 1 followed by carboplatin (area under the curve = 5) on day 1. Patients in arm 2 (n = 410) were given paclitaxel plus carboplatin as in arm 1 for eight cycles. We compared progression-free survival (PFS), overall survival, and cancer antigen-125 normalization rates in the two treatment arms. A stratified log-rank test was used to assess the primary endpoint, PFS. All statistical tests were two-sided. A total of 819 patients were randomly assigned. At baseline, the median age of the patients was 57 years (range = 28-78); 81% had received debulking surgery, and of these, 55% had less than 1 cm residual disease; 66% of patients were stage III and 388 (47.4%) patients had measurable disease. After a median follow-up of 43 months, 650 patients had disease progression or died without documented progression and 406 had died. Patients in arm 1 had more hematological toxicity and hospitalizations than patients in arm 2; PFS was 14.6 months in arm 1 vs 16.2 months in arm 2 (hazard ratio = 1.10, 95% confidence interval = 0.94 to 1.28, P = .25). Among patients with elevated baseline cancer antigen-125, fewer in arm 1 than in arm 2 had levels return to normal by 3 months after random assignment (51.6% vs 63.3%, P = .007) Topotecan and cisplatin, followed by carboplatin and paclitaxel, were more toxic than carboplatin and

  15. Combination Therapy Is Superior to Sequential Monotherapy for the Initial Treatment of Hypertension: A Double-Blind Randomized Controlled Trial.

    Science.gov (United States)

    MacDonald, Thomas M; Williams, Bryan; Webb, David J; Morant, Steve; Caulfield, Mark; Cruickshank, J Kennedy; Ford, Ian; Sever, Peter; Mackenzie, Isla S; Padmanabhan, Sandosh; McCann, Gerald P; Salsbury, Jackie; McInnes, Gordon; Brown, Morris J

    2017-11-18

    Guidelines for hypertension vary in their preference for initial combination therapy or initial monotherapy, stratified by patient profile; therefore, we compared the efficacy and tolerability of these approaches. We performed a 1-year, double-blind, randomized controlled trial in 605 untreated patients aged 18 to 79 years with systolic blood pressure (BP) ≥150 mm Hg or diastolic BP ≥95 mm Hg. In phase 1 (weeks 0-16), patients were randomly assigned to initial monotherapy (losartan 50-100 mg or hydrochlorothiazide 12.5-25 mg crossing over at 8 weeks), or initial combination (losartan 50-100 mg plus hydrochlorothiazide 12.5-25 mg). In phase 2 (weeks 17-32), all patients received losartan 100 mg and hydrochlorothiazide 12.5 to 25 mg. In phase 3 (weeks 33-52), amlodipine with or without doxazosin could be added to achieve target BP. Hierarchical primary outcomes were the difference from baseline in home systolic BP, averaged over phases 1 and 2 and, if significant, at 32 weeks. Secondary outcomes included adverse events, and difference in home systolic BP responses between tertiles of plasma renin. Home systolic BP after initial monotherapy fell 4.9 mm Hg (range: 3.7-6.0 mm Hg) less over 32 weeks (P150/95 mm Hg. URL: http://www.ClinicalTrials.gov. Unique identifier: NCT00994617. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  16. Limited clinical utility of genotype-guided warfarin initiation dosing algorithms versus standard therapy: a meta-analysis and trial sequential analysis of 11 randomized controlled trials.

    Science.gov (United States)

    Tang, H L; Shi, W L; Li, X G; Zhang, T; Zhai, S D; Xie, H G

    2015-12-01

    In terms of inconsistent conclusions across all relevant randomized controlled trials (RCTs) and available meta-analyses, we aimed to use a meta-analysis and trial sequential analysis (TSA) to evaluate whether clinical utility of a genotype-guided warfarin initiation dosing algorithm could be better than that of a standard therapy regimen, and whether currently relevant evidence could be reliable and conclusive. Overall, 11 eligible RCTs involving 2677 patients were included for further analyses. Compared with fixed dose or clinically adjusted warfarin initiation dosing regimens, genotype-guided algorithms significantly increased time in therapeutic range, shortened time to first therapeutic international normalized ratio (INR) and time to stable doses, but did not show any marked improvements in excessive anticoagulation, bleeding events, thromboembolism, or all-cause mortality. Subgroup analyses revealed that, genotype-guided algorithms showed better control in the outcomes of time in therapeutic range or excessive anticoagulation than fixed-dose regimens rather than clinically adjusted regimens. Except for excessive anticoagulation, currently available evidence of all other outcomes was unreliable and inconclusive as determined with TSA. Our findings suggest that genotype-guided warfarin initiation dosing algorithms have superiority in the improvement of surrogate quality markers for anticoagulation control, but that this does not translate into statistically significant differences in clinical outcomes, which is largely because of the insufficient sample size in the RCTs analyzed.

  17. Sequential nutrient uptake as a potential mechanism for phytoplankton to maintain high primary productivity and balanced nutrient stoichiometry

    Science.gov (United States)

    Yin, Kedong; Liu, Hao; Harrison, Paul J.

    2017-05-01

    We hypothesize that phytoplankton have the sequential nutrient uptake strategy to maintain nutrient stoichiometry and high primary productivity in the water column. According to this hypothesis, phytoplankton take up the most limiting nutrient first until depletion, continue to draw down non-limiting nutrients and then take up the most limiting nutrient rapidly when it is available. These processes would result in the variation of ambient nutrient ratios in the water column around the Redfield ratio. We used high-resolution continuous vertical profiles of nutrients, nutrient ratios and on-board ship incubation experiments to test this hypothesis in the Strait of Georgia. At the surface in summer, ambient NO3- was depleted with excess PO43- and SiO4- remaining, and as a result, both N : P and N : Si ratios were low. The two ratios increased to about 10 : 1 and 0. 45 : 1, respectively, at 20 m. Time series of vertical profiles showed that the leftover PO43- continued to be removed, resulting in additional phosphorus storage by phytoplankton. The N : P ratios at the nutricline in vertical profiles responded differently to mixing events. Field incubation of seawater samples also demonstrated the sequential uptake of NO3- (the most limiting nutrient) and then PO43- and SiO4- (the non-limiting nutrients). This sequential uptake strategy allows phytoplankton to acquire additional cellular phosphorus and silicon when they are available and wait for nitrogen to become available through frequent mixing of NO3- (or pulsed regenerated NH4). Thus, phytoplankton are able to maintain high productivity and balance nutrient stoichiometry by taking advantage of vigorous mixing regimes with the capacity of the stoichiometric plasticity. To our knowledge, this is the first study to show the in situ dynamics of continuous vertical profiles of N : P and N : Si ratios, which can provide insight into the in situ dynamics of nutrient stoichiometry in the water column and the inference of

  18. Statistical methods for mechanical characterization of randomly reinforced media

    Science.gov (United States)

    Tashkinov, Mikhail

    2017-12-01

    Advanced materials with heterogeneous microstructure attract extensive interest of researchers and engineers due to combination of unique properties and ability to create materials that are most suitable for each specific application. One of the challenging tasks is development of models of mechanical behavior for such materials since precision of the obtained numerical results highly depends on level of consideration of features of their heterogeneous microstructure. In most cases, numerical modeling of composite structures is based on multiscale approaches that require special techniques for establishing connection between parameters at different scales. This work offers a review of instruments of the statistics and the probability theory that are used for mechanical characterization of heterogeneous media with random positions of reinforcements. Such statistical descriptors are involved in assessment of correlations between the microstructural components and are parts of mechanical theories which require formalization of the information about microstructural morphology. Particularly, the paper addresses application of the instruments of statistics for geometry description and media reconstruction as well as their utilization in homogenization methods and local stochastic stress and strain field analysis.

  19. Preemptive queueing system with randomized push-out mechanism

    Science.gov (United States)

    Muliukha, Vladimir; Ilyashenko, Alexander; Zayats, Oleg; Zaborovsky, Vladimir

    2015-04-01

    In this article considered a queueing theory model with limited buffer size, one service channel, and two incoming flows. In this model one of the flows has a power to preempt other tasks. We call it a high-priority flow. Another one is low-priority. This priority mechanism is realized in a two different ways. The first one is a preemptive priority, which allows high-priority packets to interrupt low-priority packets in service channel and push them out. The second one is a randomized push-out mechanism with probability α, which allows us to choose what type of packets should be pushed out of the system when it is full. In this article we provide an algorithm for computing statistical characteristics of the model for all values of push-out probability α. We have used generating functions method to simplify the system of linear equations. This method allows us to reduce the order of linear equations system from k(k + 1)/2 to (k + 1). As the result we have got two effects in this model. The first one is a linear behavior of loss probabilities in the model with low overload. The second one is a "closing" of a system for low-priority packets with high overload.

  20. The effect of sequential therapy with lansoprazole and ecabet sodium in treating iatrogenic gastric ulcer after endoscopic submucosal dissection: a randomized prospective study.

    Science.gov (United States)

    Ahn, Ji Yong; Choi, Chang Hwan; Lee, Jang Wook; Park, Sung Jin; Kim, Jeong Wook; Chang, Sae Kyung; Han, Seung Bong

    2015-02-01

    Ecabet sodium (ES) is a new non-systemic anti-ulcer agent belonging to the category of gastroprotective agents. In this study we aimed to compare the efficacy of a combination therapy with lansoprazole (LS) followed by ES with LS alone in treating endoscopic submucosal dissection (ESD)-induced iatrogenic gastric ulcers. Patients diagnosed with gastric adenomas or early gastric cancer were randomly divided into either the LS group (30 mg once daily for 4 weeks; n = 45) or the LS + ES group (LS 30 mg once daily for one week followed by ES 1500 mg twice daily for 3 weeks; n = 45). Four weeks after ESD, a follow-up endoscopy was conducted to evaluate the proportions of ulcer reduction and ulcer stages in the two groups. In all, 79 patients were included in the final analyses. Both treatment modalities were well-tolerated in most patients, with a drug compliance of over 80%. There were no significant differences between the two groups in terms of the proportions of ulcer reduction (0.9503 ± 0.1215 in the LS group vs 0.9192 ± 0.0700 in the LS + ES group, P = 0.169) or ulcer stage (P = 0.446). The prevalence of adverse events related to drugs and bleeding were also similar between the two groups. Sequential therapy with LS + ES is as effective as LS alone against ESD-induced gastric ulcers. © 2014 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.

  1. A delayed random choice quantum mechanics experiment using light quanta

    Science.gov (United States)

    Jakubowicz, O. G.

    1984-01-01

    Wheeler has often articulated during the past seven years several delayed choice Gendanken experiments which are intended to focus attention on the meaning of the elementary quantum phenomenon. Attempts to realize a delayed choice Gendanken xperiment in the spirit John Wheeler's thinking were undertaken. Short laser pulses attenuated to the single photon detection level are introduced into a Mach-Zehnder interferometer one at a time. There is a very fast completely random choice (yes/no) optical switch in one of the arms. Any photons in that arm would be reflected out and into a photomultiplier (PMT) if the optical switch decided to be closed. And any photon in the other arm would have equal probability of going into either of the PMTs that normally monitor interference. If the optical switch chooses to leave the pathway in its arm clear (open) then the photon must split at the beamsplitter and no photons will be detected in the PMT waiting for reflections out of that arm. Additionally, the phase of the interferometer may be set beforehand so that one PMT monitoring interference will register the photon and the other PMT monitoring interference will have zero probability of photon registration. The results are consistent with conventional quantum mechanics even if the decision to block or unblock one arm of the interferometer occurs after the single photon light pulse has passed the entrance beamsplitter of the interferometer.

  2. Sequential Binding of MEIS1 and NKX2-5 on the Popdc2 Gene: A Mechanism for Spatiotemporal Regulation of Enhancers during Cardiogenesis

    Directory of Open Access Journals (Sweden)

    Laurent Dupays

    2015-10-01

    Full Text Available The homeobox transcription factors NKX2-5 and MEIS1 are essential for vertebrate heart development and normal physiology of the adult heart. We show that, during cardiac differentiation, the two transcription factors have partially overlapping expression patterns, with the result that as cardiac progenitors from the anterior heart field differentiate and migrate into the cardiac outflow tract, they sequentially experience high levels of MEIS1 and then increasing levels of NKX2-5. Using the Popdc2 gene as an example, we also show that a significant proportion of target genes for NKX2-5 contain a binding motif recognized by NKX2-5, which overlaps with a binding site for MEIS1. Binding of the two factors to such overlapping sites is mutually exclusive, and this provides a simple regulatory mechanism for spatial and temporal synchronization of a common pool of targets between NKX2-5 and MEIS1.

  3. Sequentially pulsed traveling wave accelerator

    Science.gov (United States)

    Caporaso, George J [Livermore, CA; Nelson, Scott D [Patterson, CA; Poole, Brian R [Tracy, CA

    2009-08-18

    A sequentially pulsed traveling wave compact accelerator having two or more pulse forming lines each with a switch for producing a short acceleration pulse along a short length of a beam tube, and a trigger mechanism for sequentially triggering the switches so that a traveling axial electric field is produced along the beam tube in synchronism with an axially traversing pulsed beam of charged particles to serially impart energy to the particle beam.

  4. Sequential Processing and the Matching-Stimulus Interval Effect in ERP Components: An Exploration of the Mechanism Using Multiple Regression.

    Science.gov (United States)

    Steiner, Genevieve Z; Barry, Robert J; Gonsalvez, Craig J

    2016-01-01

    In oddball tasks, increasing the time between stimuli within a particular condition (target-to-target interval, TTI; nontarget-to-nontarget interval, NNI) systematically enhances N1, P2, and P300 event-related potential (ERP) component amplitudes. This study examined the mechanism underpinning these effects in ERP components recorded from 28 adults who completed a conventional three-tone oddball task. Bivariate correlations, partial correlations and multiple regression explored component changes due to preceding ERP component amplitudes and intervals found within the stimulus series, rather than constraining the task with experimentally constructed intervals, which has been adequately explored in prior studies. Multiple regression showed that for targets, N1 and TTI predicted N2, TTI predicted P3a and P3b, and Processing Negativity (PN), P3b, and TTI predicted reaction time. For rare nontargets, P1 predicted N1, NNI predicted N2, and N1 predicted Slow Wave (SW). Findings show that the mechanism is operating on separate stages of stimulus-processing, suggestive of either increased activation within a number of stimulus-specific pathways, or very long component generator recovery cycles. These results demonstrate the extent to which matching-stimulus intervals influence ERP component amplitudes and behavior in a three-tone oddball task, and should be taken into account when designing similar studies.

  5. Cognitive-Behavioral Therapy, Behavioral Weight Loss, and Sequential Treatment for Obese Patients with Binge-Eating Disorder: A Randomized Controlled Trial

    Science.gov (United States)

    Grilo, Carlos M.; Masheb, Robin M.; Wilson, G. Terence; Gueorguieva, Ralitza; White, Marney A.

    2011-01-01

    Objective: Cognitive-behavioral therapy (CBT) is the best established treatment for binge-eating disorder (BED) but does not produce weight loss. The efficacy of behavioral weight loss (BWL) in obese patients with BED is uncertain. This study compared CBT, BWL, and a sequential approach in which CBT is delivered first, followed by BWL (CBT + BWL).…

  6. Structure and UV-vis spectrum of C(60) fullerene in ethanol: a sequential molecular dynamics/quantum mechanics study.

    Science.gov (United States)

    Malaspina, Thaciana; Fileti, Eudes E; Rivelino, Roberto

    2007-10-18

    A molecular dynamics simulation combined with semiempirical quantum mechanics calculations has been performed to investigate the structure, dynamical, and electronic properties of pure C60 in liquid ethanol. The behavior of the fullerene alcoholic solution was obtained by using the NPT ensemble under ambient conditions, including one C60 fullerene immersed in 1000 ethanol molecules. Our analyzed center-of-mass pairwise radial distribution function indicated that, on average, there are 32, 72, 132, and 187 ethanol molecules around, respectively, the first, second, third, and fourth solvation shells of the C60 molecule. To investigate the UV-vis transition energies of C60 in the presence of ethanol, we have considered constituents of the time uncorrelated supramolecular structures of the first solvation shell, i.e., clusters of C60@{EtOH}32 types. The semiempirical calculations were performed at the intermediate neglect of differential overlap level with configuration interaction singles (INDO/CIS). Our results have pointed out that the characteristic C60 UV-vis absorbance peaks are slightly shifted to longer wavelengths, as compared to the isolated molecule. These findings are in connection with the weak donor-acceptor character of the interactions involving electron lone pairs of oxygen atoms on the solvent and the fullerene surface.

  7. Early vs late tracheotomy for prevention of pneumonia in mechanically ventilated adult ICU patients: a randomized controlled trial.

    Science.gov (United States)

    Terragni, Pier Paolo; Antonelli, Massimo; Fumagalli, Roberto; Faggiano, Chiara; Berardino, Maurizio; Pallavicini, Franco Bobbio; Miletto, Antonio; Mangione, Salvatore; Sinardi, Angelo U; Pastorelli, Mauro; Vivaldi, Nicoletta; Pasetto, Alberto; Della Rocca, Giorgio; Urbino, Rosario; Filippini, Claudia; Pagano, Eva; Evangelista, Andrea; Ciccone, Gianni; Mascia, Luciana; Ranieri, V Marco

    2010-04-21

    Tracheotomy is used to replace endotracheal intubation in patients requiring prolonged ventilation; however, there is considerable variability in the time considered optimal for performing tracheotomy. This is of clinical importance because timing is a key criterion for performing a tracheotomy and patients who receive one require a large amount of health care resources. To determine the effectiveness of early tracheotomy (after 6-8 days of laryngeal intubation) compared with late tracheotomy (after 13-15 days of laryngeal intubation) in reducing the incidence of pneumonia and increasing the number of ventilator-free and intensive care unit (ICU)-free days. Randomized controlled trial performed in 12 Italian ICUs from June 2004 to June 2008 of 600 adult patients enrolled without lung infection, who had been ventilated for 24 hours, had a Simplified Acute Physiology Score II between 35 and 65, and had a sequential organ failure assessment score of 5 or greater. Patients who had worsening of respiratory conditions, unchanged or worse sequential organ failure assessment score, and no pneumonia 48 hours after inclusion were randomized to early tracheotomy (n = 209; 145 received tracheotomy) or late tracheotomy (n = 210; 119 received tracheotomy). The primary endpoint was incidence of ventilator-associated pneumonia; secondary endpoints during the 28 days immediately following randomization were number of ventilator-free days, number of ICU-free days, and number of patients in each group who were still alive. Ventilator-associated pneumonia was observed in 30 patients in the early tracheotomy group (14%; 95% confidence interval [CI], 10%-19%) and in 44 patients in the late tracheotomy group (21%; 95% CI, 15%-26%) (P = .07). During the 28 days immediately following randomization, the hazard ratio of developing ventilator-associated pneumonia was 0.66 (95% CI, 0.42-1.04), remaining connected to the ventilator was 0.70 (95% CI, 0.56-0.87), remaining in the ICU was 0.73 (95

  8. Fuzzy randomness uncertainty in civil engineering and computational mechanics

    CERN Document Server

    Möller, Bernd

    2004-01-01

    This book, for the first time, provides a coherent, overall concept for taking account of uncertainty in the analysis, the safety assessment, and the design of structures. The reader is introduced to the problem of uncertainty modeling and familiarized with particular uncertainty models. For simultaneously considering stochastic and non-stochastic uncertainty the superordinated uncertainty model fuzzy randomness, which contains real valued random variables as well as fuzzy variables as special cases, is presented. For this purpose basic mathematical knowledge concerning the fuzzy set theory and the theory of fuzzy random variables is imparted. The body of the book comprises the appropriate quantification of uncertain structural parameters, the fuzzy and fuzzy probabilistic structural analysis, the fuzzy probabilistic safety assessment, and the fuzzy cluster structural design. The completely new algorithms are described in detail and illustrated by way of demonstrative examples.

  9. Randomness in quantum mechanics: philosophy, physics and technology.

    Science.gov (United States)

    Bera, Manabendra Nath; Acín, Antonio; Kuś, Marek; Mitchell, Morgan W; Lewenstein, Maciej

    2017-12-01

    This progress report covers recent developments in the area of quantum randomness, which is an extraordinarily interdisciplinary area that belongs not only to physics, but also to philosophy, mathematics, computer science, and technology. For this reason the article contains three parts that will be essentially devoted to different aspects of quantum randomness, and even directed, although not restricted, to various audiences: a philosophical part, a physical part, and a technological part. For these reasons the article is written on an elementary level, combining simple and non-technical descriptions with a concise review of more advanced results. In this way readers of various provenances will be able to gain while reading the article.

  10. Random matrices as models for the statistics of quantum mechanics

    Science.gov (United States)

    Casati, Giulio; Guarneri, Italo; Mantica, Giorgio

    1986-05-01

    Random matrices from the Gaussian unitary ensemble generate in a natural way unitary groups of evolution in finite-dimensional spaces. The statistical properties of this time evolution can be investigated by studying the time autocorrelation functions of dynamical variables. We prove general results on the decay properties of such autocorrelation functions in the limit of infinite-dimensional matrices. We discuss the relevance of random matrices as models for the dynamics of quantum systems that are chaotic in the classical limit. Permanent address: Dipartimento di Fisica, Via Celoria 16, 20133 Milano, Italy.

  11. Randomness in quantum mechanics: philosophy, physics and technology

    Science.gov (United States)

    Nath Bera, Manabendra; Acín, Antonio; Kuś, Marek; Mitchell, Morgan W.; Lewenstein, Maciej

    2017-12-01

    This progress report covers recent developments in the area of quantum randomness, which is an extraordinarily interdisciplinary area that belongs not only to physics, but also to philosophy, mathematics, computer science, and technology. For this reason the article contains three parts that will be essentially devoted to different aspects of quantum randomness, and even directed, although not restricted, to various audiences: a philosophical part, a physical part, and a technological part. For these reasons the article is written on an elementary level, combining simple and non-technical descriptions with a concise review of more advanced results. In this way readers of various provenances will be able to gain while reading the article.

  12. Prediction of mechanical fatigue caused by multiple random excitations

    NARCIS (Netherlands)

    Bonte, M.H.A.; de Boer, Andries; Liebregts, R.

    2004-01-01

    A simulation method is presented for the fatigue analysis of automotive and other products that are subjected to multiple random excitations. The method is denoted as frequency domain stress-life fatigue analysis and was implemented in the automotive industry at DAF Trucks N.V. in Eindhoven, The

  13. A prospective randomized study comparing two commercially available types of human embryo culture media: G1-PLUS™/G2-PLUS™ sequential medium (Vitrolife) and the GL BLAST™ sole medium (Ingamed).

    Science.gov (United States)

    Ceschin, Ianae I; Ribas, Mariana H; Ceschin, Alvaro P; Nishikawa, Lucileine; Rocha, Claudia C; Pic-Taylor, Aline; Baroneza, José Eduardo

    2016-03-01

    To check the efficacy of two types of commercially available embryo culture medium: G1-PLUS™/G2-PLUS™ sequential (Vitrolife, Gothenburg, Sweden) and GV BLAST™ sole (Ingamed, Maringá, Brazil) with regards to fertilization, cleavage, blastocyst and pregnancy rates. Prospective and randomized study conducted from March to July 2015, using the medical records of 60 patients submitted to Intracytoplasmic Sperm Injection techniques (ICSI). Data regarding the age of patients, together with fertilization, cleavage, blastocyst and pregnancy rates, were collected and compared in relation to the: G1-PLUS™/G2-PLUS™ sequential and GV BLAST™ sole mediums. The data were tabulated and compared using the Pearson's Chi-Square test (95% CI). There was no significant difference when comparing patients divided into higher and lower fertility age. No significant statistical difference was noted between the fertilization rates (P=0.59), cleavage (P=0.91), evolution to blastocyst (P=0.33) and total pregnancy (P=0.83) when comparing the embryos cultured in the different media analysed. We conclude that the G1-PLUS™/G2-PLUS™ sequential and GV BLAST™ sole mediums are equally effective with regards to fertilization, cleavage, blastocyst development and total pregnancy rates.

  14. Comparison of sequential therapy and amoxicillin/tetracycline containing bismuth quadruple therapy for the first-line eradication of Helicobacter pylori: a prospective, multi-center, randomized clinical trial.

    Science.gov (United States)

    Lee, Ju Yup; Kim, Nayoung; Park, Kyung Sik; Kim, Hyun Jin; Park, Seon Mee; Baik, Gwang Ho; Shim, Ki-Nam; Oh, Jung Hwan; Choi, Suck Chei; Kim, Sung Eun; Kim, Won Hee; Park, Seon-Young; Kim, Gwang Ha; Lee, Bong Eun; Jo, Yunju; Hong, Su Jin

    2016-07-26

    The amoxicillin, could be promising because H. pylori resistance to tetracycline or to amoxicillin is relatively low. A 14-day modified bismuth quadruple protocol as first-line H. pylori treatment was compared with 10-day sequential therapy. In total, 390 H. pylori-infected subjects participated in the randomized clinical trial: 10-day sequential therapy (40 mg pantoprazole plus 1 g amoxicillin twice a day for 5 days, then 40 mg pantoprazole and 500 mg clarithromycin twice a day and 500 mg metronidazole three times a day for 5 days) or 14-day modified bismuth quadruple therapy (40 mg pantoprazole, 600 mg bismuth subcitrate, 1 g tetracycline, and 1 g amoxicillin, twice a day). (13)C-urea breath test, rapid urease testing, or histology was performed to check for eradication. Intention-to-treat (ITT) eradication rates of 10-day sequential and 14-day quadruple therapy were 74.6 % and 68.7 %, respectively, and the per-protocol (PP) rates were 84.2 and 76.5 %, respectively. The eradication rate was higher in the sequential therapy group, but neither the ITT nor the PP analyses had a significant difference (P = 0.240 and P = 0.099, respectively). However, the adverse events were significantly lower in the modified bismuth quadruple therapy group than the sequential therapy group (36.9 vs. 47.7 %, P = 0.040). Ten-day sequential therapy appears to be more effective despite frequent adverse events. However, both 10-day SQT and 14-day PBAT did not reach the excellent eradication rates that exceed 90 %. Additional trials are needed to identify a more satisfactory first-line eradication therapy. ClinicalTrials.gov ( NCT02159976 ); Registration date: 2014-06-03, CRIS ( KCT0001176 ); Registration date: 2014-07-23.

  15. Sequential Oxygenation Index and Organ Dysfunction Assessment within the First 3 Days of Mechanical Ventilation Predict the Outcome of Adult Patients with Severe Acute Respiratory Failure

    Directory of Open Access Journals (Sweden)

    Hsu-Ching Kao

    2013-01-01

    Full Text Available Objective. To determine early predictors of outcomes of adult patients with severe acute respiratory failure. Method. 100 consecutive adult patients with severe acute respiratory failure were evaluated in this retrospective study. Data including comorbidities, Sequential Organ Failure Assessment (SOFA score, Acute Physiological Assessment and Chronic Health Evaluation II (APACHE II score, PaO2, FiO2, PaO2/FiO2, PEEP, mean airway pressure (mPaw, and oxygenation index (OI on the 1st and the 3rd day of mechanical ventilation, and change in OI within 3 days were recorded. Primary outcome was hospital mortality; secondary outcome measure was ventilator weaning failure. Results. 38 out of 100 (38% patients died within the study period. 48 patients (48% failed to wean from ventilator. Multivariate analysis showed day 3 OI ( and SOFA ( score were independent predictors of hospital mortality. Preexisting cerebrovascular accident (CVA ( was the predictor of weaning failure. Results from Kaplan-Meier method demonstrated that higher day 3 OI was associated with shorter survival time (log-Rank test, . Conclusion. Early OI (within 3 days and SOFA score were predictors of mortality in severe acute respiratory failure. In the future, prospective studies measuring serial OIs in a larger scale of study cohort is required to further consolidate our findings.

  16. A Randomized study on the Effects of Paclitaxel Liposme and Cisplatin Induction Chemotherapy Followed Concurrent Chemoradiotherapy and Sequential Radiotherapy on Locally Advanced Non-small Cell Lung Cancer Patients

    Directory of Open Access Journals (Sweden)

    Youyi DAI

    2011-02-01

    Full Text Available Background and objective Sequential and concurrent chemoradiotherapy were widely studied in locally advanced non-small cell lung cancer (NSCLC, but the reports of induction chemotherapy followed concurrent chemoradiotherapy are rare so far. The little side effects of paclitaxel liposme may be convenient to carry out induction chemotherapy followed concurrent chemoradiotherapy. The aim of this study is to compare the effects and side effects of TP regimen (Paclitaxel liposme and cisplatin induction chemotherapy followed concurrent chemoradiotherapy with sequential radiotherapy on locally advanced NSCLC. Methods Sixty locally advanced NSCLC patients were randomly divided into group A, induction chemotherapy followed concurrent chemoradiotherapy and group B, sequential radiotherapy group. The patients in group A received 2-3 cycles of induced chemotherapy included of Paclitaxel liposme 135 mg/m2-175 mg/m2, d1 and cisplatin 70 mg/m2-80 mg/m2, d2, 3 weeks repeat and after 2-3 cycles followed by concurrent chemoradiotherapy. The patients in group B received chemotherapy, (as described above in group A 4-6 cycles of chemotherapy followed one cycle of radiotherapy. The three-dimensional conformal radiotherapy at the total dose of 56 Gy-70 Gy was applied in all patients. Results The response rate in group A and group B were 80.3% and 60%, respectively (P=0.042. 1-year survival rates were 71.4% and 53.2%, respectively (P=0.18. And there were no significant difference of myelosuppression, radiation esophagitis and pulmonary fibrosis between the two groups (P=0.09, P=0.147, P=0.276, respectively. Conclusion The recent effects of induction chemotherapy followed by concurrent chemoradiotherapy group were better than sequential radiotherapy group on locally advanced NSCLC and there was no significant difference in side effects between the two groups.

  17. Power Delivered to Mechanical Systems by Random Vibrations

    Directory of Open Access Journals (Sweden)

    Timothy S. Edwards

    2009-01-01

    Full Text Available This paper develops deformational response power descriptions of multiple degree-of-freedom systems due to stationary random vibration excitation. Two new concepts are developed. The deformational response power density (DRPD can be computed when a structure's natural frequencies and modal masses are available. The DRPD shows the spectral content of the deformational power delivered to a specific structure by the stationary, random excitation. This function can be found through a weighted windowing of the power spectrum of the input acceleration excitation. Deformational response input power spectra (DRIPS, similar to the input energy spectrum and shock response spectrum, give the power delivered to single-degree-of-freedom systems as a function of natural frequency. It is shown that the DRIPS is simply a smoothed version of the power spectrum of the input acceleration excitation. The DRIPS gives rise to a useful power-based data smoothing operation.

  18. Randomness in quantum mechanics - nature's ultimate cryptogram

    Energy Technology Data Exchange (ETDEWEB)

    Erber, T.; Putterman, S.

    1985-11-07

    Will a single atom irradiated by coherent light be equivalent to an infinite computer as regards its ability to generate random numbers. As described in the paper, a search for unexpected patterns of order by cryptanalysis of the telegraph signal generated by the on/off time of the atom's fluorescence will provide new experimental tests of the fundamental principles of the quantum theory. (author).

  19. Evaluation of the prognostic and predictive value of HER-1/EGFR in breast cancer patients participating in a randomized study with dose-dense sequential adjuvant chemotherapy.

    Science.gov (United States)

    Tzaida, Olympia; Gogas, Helen; Dafni, Urania; Kyroudi, Aspasia; Papaspyrou, Irene; Kyriakou, Vasiliki; Malamou-Mitsi, Vasiliki; Alamani, Maria; Skopa, Chrisoula; Kostopoulos, Ioannis; Kastritis, Efstathios; Pectasides, Dimitrios; Briasoulis, Evangelos; Kalofonos, Haralabos P; Aravantinos, Gerasimos; Fountzilas, George; Arapantoni-Dadioti, Petroula

    2007-01-01

    To assess the prognostic and predictive significance of HER-1/EGFR protein levels in high-risk patients with breast cancer treated with dose-dense sequential adjuvant chemotherapy. 595 high-risk breast cancer patients were treated with adjuvant anthracycline-based dose-dense sequential chemotherapy (E-CMF vs. E-T-CMF). Disease-free survival (DFS) was the primary end point. HER-1/EGFR was assessed by immunohistochemistry (IHC) in 312 patients. HER-1/EGFR expression was detected in 54 of 312 patients (17%). Positive expression of HER-1/EGFR was significantly associated with negative receptor status (52 vs. 17%, p HER-1/EGFR effect on the risk of disease progression was different according to treatment (interaction p = 0.02). Regarding overall survival, a trend towards a significant difference for an interaction of HER-1/EGFR and treatment was found (p = 0.07). The present study demonstrated a differential effect of positive HER-1/EGFR expression in the two treatment groups, with HER-1/EGFR being a negative prognostic marker in the absence of paclitaxel. (c) 2008 S. Karger AG, Basel

  20. Contact mechanics for layered materials with randomly rough surfaces.

    Science.gov (United States)

    Persson, B N J

    2012-03-07

    The contact mechanics model of Persson is applied to layered materials. We calculate the M function, which relates the surface stress to the surface displacement, for a layered material, where the top layer (thickness d) has different elastic properties than the semi-infinite solid below. Numerical results for the contact area as a function of the magnification are presented for several cases. As an application, we calculate the fluid leak rate for laminated rubber seals.

  1. Instrumental variable analyses. Exploiting natural randomness to understand causal mechanisms.

    Science.gov (United States)

    Iwashyna, Theodore J; Kennedy, Edward H

    2013-06-01

    Instrumental variable analysis is a technique commonly used in the social sciences to provide evidence that a treatment causes an outcome, as contrasted with evidence that a treatment is merely associated with differences in an outcome. To extract such strong evidence from observational data, instrumental variable analysis exploits situations where some degree of randomness affects how patients are selected for a treatment. An instrumental variable is a characteristic of the world that leads some people to be more likely to get the specific treatment we want to study but does not otherwise change those patients' outcomes. This seminar explains, in nonmathematical language, the logic behind instrumental variable analyses, including several examples. It also provides three key questions that readers of instrumental variable analyses should ask to evaluate the quality of the evidence. (1) Does the instrumental variable lead to meaningful differences in the treatment being tested? (2) Other than through the specific treatment being tested, is there any other way the instrumental variable could influence the outcome? (3) Does anything cause patients to both receive the instrumental variable and receive the outcome?

  2. Mechanisms within the Parietal Cortex Correlate with the Benefits of Random Practice in Motor Adaptation

    Directory of Open Access Journals (Sweden)

    Benjamin Thürer

    2017-08-01

    Full Text Available The motor learning literature shows an increased retest or transfer performance after practicing under unstable (random conditions. This random practice effect (also known as contextual interference effect is frequently investigated on the behavioral level and discussed in the context of mechanisms of the dorsolateral prefrontal cortex and increased cognitive efforts during movement planning. However, there is a lack of studies examining the random practice effect in motor adaptation tasks and, in general, the underlying neural processes of the random practice effect are not fully understood. We tested 24 right-handed human subjects performing a reaching task using a robotic manipulandum. Subjects learned to adapt either to a blocked or a random schedule of different force field perturbations while subjects’ electroencephalography (EEG was recorded. The behavioral results showed a distinct random practice effect in terms of a more stabilized retest performance of the random compared to the blocked practicing group. Further analyses showed that this effect correlates with changes in the alpha band power in electrodes over parietal areas. We conclude that the random practice effect in this study is facilitated by mechanisms within the parietal cortex during movement execution which might reflect online feedback mechanisms.

  3. Random surfaces in statistical mechanics: roughening, rounding, wetting

    Energy Technology Data Exchange (ETDEWEB)

    Bricmont, J.; El Mellouki, A.; Frohlich, J.

    1986-03-01

    The authors study several problems in statistical mechanics involving systems of fluctuating extended objects such as interacting steps and domain walls. They consider the roughening transition and relate it to the free energy of a gas of steps and to the rounding of facets in the equilibrium shape of crystals defined via the Wulff construction. Using an idealized description due to Fisher and Fisher the authors analyze the commensurate-incommensurate transition in uniaxial systems in terms of a gas of interacting domain walls. They also study the interactions between a domain wall and a rigid wall and between two interfaces, a problem which is central for the understanding of wetting. Among their results are a quantitative analysis of entropic repulsion between extended objects and a calculation of deviations from mean-field theory in the commensurate-incommensurate transition in dimensional range limited between 2 and 3.

  4. Rational design of soft mechanical metamaterials: Independent tailoring of elastic properties with randomness

    Science.gov (United States)

    Mirzaali, M. J.; Hedayati, R.; Vena, P.; Vergani, L.; Strano, M.; Zadpoor, A. A.

    2017-07-01

    The elastic properties of mechanical metamaterials are direct functions of their topological designs. Rational design approaches based on computational models could, therefore, be used to devise topological designs that result in the desired properties. It is of particular importance to independently tailor the elastic modulus and Poisson's ratio of metamaterials. Here, we present patterned randomness as a strategy for independent tailoring of both properties. Soft mechanical metamaterials incorporating various types of patterned randomness were fabricated using an indirect additive manufacturing technique and mechanically tested. Computational models were also developed to predict the topology-property relationship in a wide range of proposed topologies. The results of this study show that patterned randomness allows for independent tailoring of the elastic properties and covering a broad area of the elastic modulus-Poisson's ratio plane. The uniform and homogenous topologies constitute the boundaries of the covered area, while topological designs with patterned randomness fill the enclosed area.

  5. Efficacy of Short-Term Antiarrhythmic Drugs Use after Catheter Ablation of Atrial Fibrillation-A Systematic Review with Meta-Analyses and Trial Sequential Analyses of Randomized Controlled Trials.

    Science.gov (United States)

    Chen, Weijie; Liu, Hang; Ling, Zhiyu; Xu, Yanping; Fan, Jinqi; Du, Huaan; Xiao, Peilin; Su, Li; Liu, Zengzhang; Lan, Xianbin; Zrenner, Bernhard; Yin, Yuehui

    2016-01-01

    The efficacy of short-term antiarrhythmic drugs (AADs) use compared with no-AADs prescription after catheter ablation of atrial fibrillation (AF) in preventing atrial arrhythmia recurrence is uncertain. We searched PubMed, Embase, and the Cochrane Library through December 2015 to identify randomized controlled trials (RCTs) which evaluated the efficacy of short-term AADs use compared with no-AADs prescription after AF ablation in preventing atrial arrhythmia recurrence. The primary outcome was labeled as early atrial arrhythmia recurrence within 3 months after ablation. Secondary outcome was defined as late recurrence after 3 months of ablation. Random-effects model or fixed-effects model was used to estimate relative risks (RRs) with 95% confidence intervals (CIs). Six RCTs with 2,667 patients were included into this meta-analysis. Compared with no-AADs administration after AF ablation, short-term AADs use was associated with significant reduction of early atrial arrhythmia recurrence (RR, 0.68; 95% CI, 0.52-0.87; p = 0.003). Trial sequential analysis (TSA) showed that the cumulative Z-curve crossed the trial sequential monitoring boundary for benefit, establishing sufficient and conclusive evidence. However, compared with no-AADs prescription, short-term AADs use after AF ablation didn't significantly reduce the risk of late atrial arrhythmia recurrence (RR, 0.92; 95% CI, 0.83-1.03; p = 0.15). TSA supported this result; meanwhile the estimated required information size (1,486 patients) was also met. Short-term use of AADs after AF ablation can significantly decrease the risk of early atrial arrhythmia recurrence but not lead to corresponding reduction in risk of late atrial arrhythmia recurrence.

  6. Immediate Sequential Bilateral Cataract Surgery

    DEFF Research Database (Denmark)

    Kessel, Line; Andresen, Jens; Erngaard, Ditte

    2015-01-01

    The aim of the present systematic review was to examine the benefits and harms associated with immediate sequential bilateral cataract surgery (ISBCS) with specific emphasis on the rate of complications, postoperative anisometropia, and subjective visual function in order to formulate evidence......-based national Danish guidelines for cataract surgery. A systematic literature review in PubMed, Embase, and Cochrane central databases identified three randomized controlled trials that compared outcome in patients randomized to ISBCS or bilateral cataract surgery on two different dates. Meta-analyses were...... performed using the Cochrane Review Manager software. The quality of the evidence was assessed using the GRADE method (Grading of Recommendation, Assessment, Development, and Evaluation). We did not find any difference in the risk of complications or visual outcome in patients randomized to ISBCS or surgery...

  7. Solvatochromic shifts of polar and non-polar molecules in ambient and supercritical water: a sequential quantum mechanics/molecular mechanics study including solute-solvent electron exchange-correlation.

    Science.gov (United States)

    Ma, Haibo; Ma, Yingjin

    2012-12-07

    Polar and non-polar solutes (acetone and benzene) dissolved in ambient water and supercritical water are investigated theoretically using a sequential quantum mechanics (QM)/molecular mechanics (MM) method which combines classical molecular dynamics simulations and QM/MM calculations. From the detailed analysis of the dependence of the QM region size and point charge background region size as well as the different functionals, it is found that the inclusion of the solvent molecules within the first solvation shell into the QM region to account for the exchange-correlation between a solute and neighboring solvent molecules is important for the highly accurate spectral shift calculations, especially vital for the non-polar solutes whose interactions with the solvents are dominated by the quantum dispersions. At the same time, sufficiently large surrounding partial charge region (r(cutoff) ≥15 Å) as well as the functional corrections to describe the long-range dispersion-corrections are also essential for the study of the electronic excited states in condensed phase. Our calculated solvatochromic shift values and their density dependencies at ambient and high temperature conditions are found to be in good agreements with experimental observations. This indicates that sound theoretical studies of solvatochromic shift can be achieved provided that a reasonable computational scheme with sufficiently large N(water) (QM) and r(cutoff) values is implemented. We also find both of aqueous acetone and aqueous benzene under high temperatures present three distinctive regions: low-density gas-like region, supercritical region, and high-density liquid-like region. The plateau behavior of solvatochromic shift in the supercritical region can be ascribed to the solvent clustering around the solute, which is a fundamental phenomenon of supercritical fluids (SCFs). The density dependence of our calculated coordination number of the first solvation shell nicely reproduces the trend

  8. A Team Study of a Multiple-Power Wireless Random Channel Access Mechanism with Capture Effect

    Directory of Open Access Journals (Sweden)

    Abdelillah Karouit

    2013-01-01

    Full Text Available We present a team analysis of a slotted random wireless channel access mechanism. Under the proposed scheme, denoted wireless random access mechanism with multiple power levels (MPL-WRA, each mobile station contends for a transmission opportunity following the principles of a slotted access mechanism incorporating a random transmitting power value selected among various available power levels. In this way, a capture effect may be produced allowing the packet to be decoded whenever the signal-to-interference-plus-noise ratio is higher than a given threshold. In order to analyze the performance and optimization of the proposed setup, we build a Markovian model integrating the wireless access mechanism supplemented by the use of multiple power levels in an attractive and simple cross-layer fashion. We follow a team problem approach allowing us to fine tune the design parameters of the overall system configuration. Throughout an extensive numerical analysis, our main results set the basis for the social optimal system configuration of the proposed mechanism taking into account the physical constraints of using multiple power levels and the actual practical implementation of a slotted access mechanism. We end the paper with concluding remarks and future research directions including guidelines for the actual implementation of our proposal.

  9. A prospective and randomized study of radiotherapy, sequential chemotherapy radiotherapy and concomitant chemo therapy-radiotherapy in unresectable non small cell carcinoma of the lung

    Directory of Open Access Journals (Sweden)

    Dasgupta Anirban

    2006-01-01

    Full Text Available Purpose: Treatment of advanced Non small cell lung cancer (NSCLC often produces dismal results. Combination of available treatment modalities has reportedly improved the outcome. A prospectively randomized trial was conducted, comparing combined treatment modalities versus radiotherapy alone, in treatment of unresectable NSCLC. Materials and Methods: A total of 103 patients were randomized to three groups. In group ′A′, 32 patients received radiotherapy alone (6500 cGy/30 fraction. In group ′B′, 35 patients received neoadjuvant chemotherapy (Cisplatin 80 mg/m2 on day 1 and Etoposide 100 mg/m day 1-3 intravenously q3 weeks for 3 cycles, followed by radiotherapy (6000 cGy/30 fractions and 3 more cycles of Chemotherapy, with the same regimen. In group ′C′, 36 patients received radiotherapy (5000 cGy/25 fractions with concurrent chemotherapy (ciplatin 20 mg/m2 + Etoposide 75 mg/m2 intravenously on day 1-5 and day 22-26, followed by 2 more cycles of chemotherapy,q3 weeks with the same regimen. Results: Initial treatment responses were significantly higher in group ′B′ ( P P Conclusion: Addition of chemotherapy with radiation in unresectable NSCLC improves response rates, time to tumour progression and disease free survival, though the same effect is not translated in overall survival.

  10. Panchromatic Sequentially Cast Ternary Polymer Solar Cells.

    Science.gov (United States)

    Ghasemi, Masoud; Ye, Long; Zhang, Qianqian; Yan, Liang; Kim, Joo-Hyun; Awartani, Omar; You, Wei; Gadisa, Abay; Ade, Harald

    2017-01-01

    A sequential-casting ternary method is developed to create stratified bulk heterojunction (BHJ) solar cells, in which the two BHJ layers are spin cast sequentially without the need of adopting a middle electrode and orthogonal solvents. This method is found to be particularly useful for polymers that form a mechanically alloyed morphology due to the high degree of miscibility in the blend. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Growth of rutile TiO2 nanorods in Ti and Cu ion sequentially implanted SiO2 and the involved mechanisms

    Science.gov (United States)

    Mu, Xiaoyu; Liu, Xiaoyu; Wang, Xiaohu; Dai, Haitao; Liu, Changlong

    2018-01-01

    TiO2 in nanoscale exhibits unique physicochemical and optoelectronic properties and has attracted much more interest of the researchers. In this work, TiO2 nanostructures are synthesized in amorphous SiO2 slices by implanting Ti ions, or sequentially implanting Ti and Cu ions combined with annealing at high temperature. The morphology, structure, spatial distribution and optical properties of the formed nanostructures have been investigated in detail. Our results clearly show that the thermal growth of TiO2 nanostructures in SiO2 substrate is significantly enhanced by presence of post Cu ion implantation, which depends strongly on the applied Cu ion fluence, as well as the annealing atmosphere. Due to the formation of Cu2O in the substrate, rutile TiO2 nanorods of large size have been well fabricated in the Ti and Cu sequentially implanted SiO2 after annealing in N2 atmosphere, in which Cu2O plays a role as a catalyst. Moreover, the sample with well-fabricated TiO2 nanorods exhibits a narrowed band gap, an enhanced optical absorption in visible region, and catalase-/peroxidase-like catalytic characteristics. Our findings provide an effective route to fabricate functional TiO2 nanorods in SiO2 via ion implantation.

  12. Early percutaneous tracheotomy versus prolonged intubation of mechanically ventilated patients after cardiac surgery: a randomized trial.

    Science.gov (United States)

    Trouillet, Jean-Louis; Luyt, Charles-Edouard; Guiguet, Marguerite; Ouattara, Alexandre; Vaissier, Elisabeth; Makri, Ralouka; Nieszkowska, Ania; Leprince, Pascal; Pavie, Alain; Chastre, Jean; Combes, Alain

    2011-03-15

    Whether early percutaneous tracheotomy in patients who require prolonged mechanical ventilation can shorten mechanical ventilation duration and lower mortality remains controversial. To compare the outcomes of severely ill patients who require prolonged mechanical ventilation randomly assigned to early percutaneous tracheotomy or prolonged intubation. Prospective, randomized, controlled, single-center trial (ClinicalTrials.gov registration number: NCT00347321). Academic center. 216 adults requiring mechanical ventilation 4 or more days after cardiac surgery. Immediate early percutaneous tracheotomy or prolonged intubation with tracheotomy 15 days after randomization. The primary end point was the number of ventilator-free days during the first 60 days after randomization. Secondary outcomes included 28-, 60-, or 90-day mortality rates; durations of mechanical ventilation, intensive care unit stay, and hospitalization; sedative, analgesic, and neuroleptic use; ventilator-associated pneumonia rate; unscheduled extubations; comfort and ease of care; and long-term health-related quality of life (HRQoL) and psychosocial evaluations. There was no difference in ventilator-free days during the first 60 days after randomization between early percutaneous tracheotomy and prolonged intubation groups (mean, 30.4 days [SD, 22.4] vs. 28.3 days [SD, 23.7], respectively; absolute difference, 2.1 days [95% CI, -4.1 to 8.3 days]) nor in 28-, 60-, or 90-day mortality rates (16% vs. 21%, 26% vs. 28%, and 30% vs. 30%, respectively). The durations of mechanical ventilation and hospitalization, as well as frequencies of ventilator-associated pneumonia and other severe infections, were also similar. However, early percutaneous tracheotomy was associated with less intravenous sedation; less time of heavy sedation; less haloperidol use for agitation, delirium, or both; fewer unscheduled extubations; better comfort and ease of care; and earlier resumption of oral nutrition. After a median

  13. A PROSPECTIVE RANDOMIZED TRIAL COMPARING SEQUENTIAL GANCICLOVIR-HIGH DOSE ACYCLOVIR TO HIGH DOSE ACYCLOVIR FOR PREVENTION OF CYTOMEGALOVIRUS DISEASE IN ADULT LIVER TRANSPLANT RECIPIENTS

    Science.gov (United States)

    Martin, Maureen; Mañez, Rafael; Linden, Peter; Estores, David; Torre-Cisneros, Julian; Kusne, Shimon; Ondick, Linnea; Ptachcinski, Richard; Irish, William; Kisor, David; Felser, Ilene; Rinaldo, Charles; Stieber, Andrei; Fung, John; Ho, Monto; Simmons, Richard; Starzl, Thomas

    2010-01-01

    Cytomegalovirus disease is an important cause of morbidity following liver transplantation. To date there has not been an effective prophylaxis for CMV disease after liver transplantation. One hundred forty-three patients were randomized to receive either high dose oral acyclovir (800 mg 4 times a day) alone for 3 months after transplantation (acyclovir group) or intravenous ganciclovir (5 mg/kg twice a day) for 14 days followed by high dose oral acyclovir to complete a 3-month regimen (ganciclovir group). Of 139 patients available for evaluation, 43 of 71 (61%) patients from the acyclovir group developed CMV infection compared with 16 of 68 (24%) from the ganciclovir group (relative risk, 3.69; 95% confidence interval, 2.07–6.56; Pganciclovir group (relative risk, 5.11; 95% confidence interval, 2.05–12.75; P=0.000l). The median time to onset of CMV infection was 45 days in the acyclovir group compared with 78 days in the ganciclovir group (P=0.004). The median time to onset of CMV disease was 40 days in the acyclovir group compared with 78 days in the ganciclovir patients (P=0.02). With respect to primary CMV infection, there was no difference in the rates in the 2 groups, but tissue invasive disease and recurrent CMV disease were less frequent in the ganciclovir group. It is concluded that a course of 2 weeks of ganciclovir immediately after transplantation followed by high dose oral acyclovir for 10 weeks is superior to a 12-week course of high dose oral acyclovir alone for prevention of both CMV infection and CMV disease after liver transplantation. However, the lack of significant effect in seronegative recipients who received grafts from seropositive donors suggests that other strategies are needed to prevent CMV infection in this high risk population. PMID:7940710

  14. Is Patch It® better than placebo in alleviating swelling and ache in the lower legs and feet? A randomized, placebo-controlled, double blind, crossover, sequential trial

    Directory of Open Access Journals (Sweden)

    Shakeel A

    2012-04-01

    Full Text Available Aliya Shakeel1, Hoong Keong Hui2, Chetan S Patil3, Manojkumar V Chaudhari4, Yogesh D Kadam5, Shrikant V Pensalwar6, Suhas G Erande7, Rajesh M Kewalramani81Vedic Lifesciences Pvt Ltd, Mumbai, Maharashtra, India; 2Nutriworks Limited, Kowloon, Hong Kong; 3Muktai Hospital, Nasik, 4Bhagirathi Medical Foundation, 5Poona Diabetes Center, 6Balaji Clinic, Mumbai, 7Akshay Hospital, Pune, 8Shanti Niketan, Kandar Pada, Dahisar, Mumbai, Maharashtra, IndiaBackground: Existing therapeutic measures for swelling, aching and discomfort in the lower limbs, which include compression stockings and leg elevation, are difficult to use and inconvenient. Patch It®, a proprietary herbomineral patch is an easy-to-use alternative therapy. This trial was conducted to compare it's efficacy against that of a placebo in swollen and aching lower legs and feet.Methods: This randomized, placebo-controlled, double blind, crossover, sequential trial was conducted in the private clinics of physicians. A total of 100 patients (24 men and 76 women, aged 25 to 60 years, with recurring swelling in the feet and (optionally up to two more related complaints, having an average visual analog score (VAS of at least 60 (scale 0–100 for each complaint were recruited into the study. Patches (active or placebo were applied to both soles overnight for 8 weeks: 4 consecutive weeks each with active or placebo in randomized sequence. Outcome measures included the average VAS score (baseline to week 4, and week 5 to week 8, preference for either patch (difference of >5 mm in average VAS score reduction, ankle figure-of-eight measures, investigator's global assessment (good, fair, poor, patient's willingness to continue using the patch after the trial (yes, no, and adverse events.Results: Out of 100 patients, 86 completed the trial, while ten were excluded for noncompliance, three withdrew, and one was lost to follow-up. The active placebo boundary of the sequential chart was crossed when 82

  15. A single-blinded randomized controlled study to assess the efficacy of twice daily application of sinecatechins 15% ointment when used sequentially with cryotherapy in the treatment of external genital warts.

    Science.gov (United States)

    On, Shelbi C Jim; Linkner, Rita V; Haddican, Madelaine; Yaroshinsky, Alex; Gagliotti, Matthew; Singer, Giselle; Goldenberg, Gary

    2014-11-01

    To evaluate the efficacy of sequential therapy of cryotherapy and sinecatechins 15% ointment BID versus cryotherapy alone in treatment of external genital warts (EGW). Forty-two subjects with at least two EGW lesions underwent cryotherapy to all lesions. One week following cryotherapy, subjects were randomized 1:1 to receive either no additional treatment or treatment with sinecatechins 15% ointment BID up to 16 weeks or until complete clearance. The total number of visible baseline and new EGW were recorded at each visit. Subjects were followed for a total of 65 weeks post-treatment. There was a significant reduction in mean number of lesions from baseline after 16 weeks of treatment in the cryotherapy-sinecatechins ointment group compared to cryotherapy alone (-5.0 lesions vs -2.1 lesions respectively, P=0.07). Cryotherapy plus sinecatechins 15% ointment BID resulted in a significant improvement in the reduction of EGW compared to cryotherapy alone. Clinicaltrials.gov registration identifier: NCT02147353.

  16. The statistical mechanics of random set packing and a generalization of the Karp-Sipser algorithm

    OpenAIRE

    Lucibello, C.; Ricci-Tersenghi, F.

    2013-01-01

    We analyse the asymptotic behaviour of random instances of the Maximum Set Packing (MSP) optimization problem, also known as Maximum Matching or Maximum Strong Independent Set on Hypergraphs. We give an analytical prediction of the MSPs size using the 1RSB cavity method from statistical mechanics of disordered systems. We also propose a heuristic algorithm, a generalization of the celebrated Karp-Sipser one, which allows us to rigorously prove that the replica symmetric cavity method predicti...

  17. ABCLS method for high-reliability aerospace mechanism with truncated random uncertainties

    Directory of Open Access Journals (Sweden)

    Peng Wensheng

    2015-08-01

    Full Text Available The random variables are always truncated in aerospace engineering and the truncated distribution is more feasible and effective for the random variables due to the limited samples available. For high-reliability aerospace mechanism with truncated random variables, a method based on artificial bee colony (ABC algorithm and line sampling (LS is proposed. The artificial bee colony-based line sampling (ABCLS method presents a multi-constrained optimization model to solve the potential non-convergence problem when calculating design point (is also as most probable point, MPP of performance function with truncated variables; by implementing ABC algorithm to search for MPP in the standard normal space, the optimization efficiency and global searching ability are increased with this method dramatically. When calculating the reliability of aerospace mechanism with too small failure probability, the Monte Carlo simulation method needs too large sample size. The ABCLS method could overcome this drawback. For reliability problems with implicit functions, this paper combines the ABCLS with Kriging response surface method, therefore could alleviate computational burden of calculating the reliability of complex aerospace mechanism. A numerical example and an engineering example are carried out to verify this method and prove the applicability.

  18. Sequential stochastic optimization

    CERN Document Server

    Cairoli, Renzo

    1996-01-01

    Sequential Stochastic Optimization provides mathematicians and applied researchers with a well-developed framework in which stochastic optimization problems can be formulated and solved. Offering much material that is either new or has never before appeared in book form, it lucidly presents a unified theory of optimal stopping and optimal sequential control of stochastic processes. This book has been carefully organized so that little prior knowledge of the subject is assumed; its only prerequisites are a standard graduate course in probability theory and some familiarity with discrete-paramet

  19. Effects of Natural Sounds on Pain: A Randomized Controlled Trial with Patients Receiving Mechanical Ventilation Support.

    Science.gov (United States)

    Saadatmand, Vahid; Rejeh, Nahid; Heravi-Karimooi, Majideh; Tadrisi, Sayed Davood; Vaismoradi, Mojtaba; Jordan, Sue

    2015-08-01

    Nonpharmacologic pain management in patients receiving mechanical ventilation support in critical care units is under investigated. Natural sounds may help reduce the potentially harmful effects of anxiety and pain in hospitalized patients. The aim of this study was to examine the effect of pleasant, natural sounds on self-reported pain in patients receiving mechanical ventilation support, using a pragmatic parallel-arm, randomized controlled trial. The study was conducted in a general adult intensive care unit of a high-turnover teaching hospital, in Tehran, Iran. Between October 2011 and June 2012, we recruited 60 patients receiving mechanical ventilation support to the intervention (n = 30) and control arms (n = 30) of a pragmatic parallel-group, randomized controlled trial. Participants in both arms wore headphones for 90 minutes. Those in the intervention arm heard pleasant, natural sounds, whereas those in the control arm heard nothing. Outcome measures included the self-reported visual analog scale for pain at baseline; 30, 60, and 90 minutes into the intervention; and 30 minutes post-intervention. All patients approached agreed to participate. The trial arms were similar at baseline. Pain scores in the intervention arm fell and were significantly lower than in the control arm at each time point (p mechanical ventilation support. Copyright © 2015 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  20. Music preferences of mechanically ventilated patients participating in a randomized controlled trial.

    Science.gov (United States)

    Heiderscheit, Annie; Breckenridge, Stephanie J; Chlan, Linda L; Savik, Kay

    2014-01-01

    Mechanical ventilation (MV) is a life-saving measure and supportive modality utilized to treat patients experiencing respiratory failure. Patients experience pain, discomfort, and anxiety as a result of being mechanically ventilated. Music listening is a non-pharmacological intervention used to manage these psychophysiological symptoms associated with mechanical ventilation. The purpose of this secondary analysis was to examine music preferences of 107 MV patients enrolled in a randomized clinical trial that implemented a patient-directed music listening protocol to help manage the psychophysiological symptom of anxiety. Music data presented includes the music genres and instrumentation patients identified as their preferred music. Genres preferred include: classical, jazz, rock, country, and oldies. Instrumentation preferred include: piano, voice, guitar, music with nature sounds, and orchestral music. Analysis of three patients' preferred music received throughout the course of the study is illustrated to demonstrate the complexity of assessing MV patients and the need for an ongoing assessment process.

  1. Chronic heart failure modifies respiratory mechanics in rats: a randomized controlled trial.

    Science.gov (United States)

    Pacheco, Deise M; Silveira, Viviane D; Thomaz, Alex; Nunes, Ramiro B; Elsner, Viviane R; Dal Lago, Pedro

    2016-01-01

    To analyze respiratory mechanics and hemodynamic alterations in an experimental model of chronic heart failure (CHF) following myocardial infarction. Twenty-seven male adult Wistar rats were randomized to CHF group (n=12) or Sham group (n=15). Ten weeks after coronary ligation or sham surgery, the animals were anesthetized and submitted to respiratory mechanics and hemodynamic measurements. Pulmonary edema as well as cardiac remodeling were measured. The CHF rats showed pulmonary edema 26% higher than the Sham group. The respiratory system compliance (Crs) and the total lung capacity (TLC) were lower (40% and 27%, respectively) in the CHF rats when compared to the Sham group (Prespiratory mechanics, which may be associated with alterations in cardiopulmonary interactions.

  2. Music preferences of mechanically ventilated patients participating in a randomized controlled trial

    Science.gov (United States)

    Heiderscheit, Annie; Breckenridge, Stephanie J.; Chlan, Linda L.; Savik, Kay

    2014-01-01

    Mechanical ventilation (MV) is a life-saving measure and supportive modality utilized to treat patients experiencing respiratory failure. Patients experience pain, discomfort, and anxiety as a result of being mechanically ventilated. Music listening is a non-pharmacological intervention used to manage these psychophysiological symptoms associated with mechanical ventilation. The purpose of this secondary analysis was to examine music preferences of 107 MV patients enrolled in a randomized clinical trial that implemented a patient-directed music listening protocol to help manage the psychophysiological symptom of anxiety. Music data presented includes the music genres and instrumentation patients identified as their preferred music. Genres preferred include: classical, jazz, rock, country, and oldies. Instrumentation preferred include: piano, voice, guitar, music with nature sounds, and orchestral music. Analysis of three patients’ preferred music received throughout the course of the study is illustrated to demonstrate the complexity of assessing MV patients and the need for an ongoing assessment process. PMID:25574992

  3. Random Electromyostimulation Promotes Osteogenesis and the Mechanical Properties of Rat Bones.

    Science.gov (United States)

    Tanaka, Shigeo M; Yorozuya, Yuma; Takatsu, Daisuke

    2017-12-01

    Exercise is often recommended as a promising non-pharmacologic countermeasure to prevent osteoporosis. However, elderly osteoporotic patients generally have physical fitness difficulties preventing them from performing effective and sustainable exercise. Electromyostimulation should be one effective modality for non-pharmacological prevention of osteoporosis without any voluntary physical movements. However, successful stimulation patterns remain controversial. As suggested by our previous in vitro studies, randomized timing of stimulation could be a candidate to maximize the osteogenic effect of electromyostimulation. In this study, the effects of random stimulation to the quadriceps on osteogenesis in the femurs were investigated using rats, in comparison with a periodic stimulation pattern. In histomorphometric assessments, both stimulation patterns demonstrated increases in bone formation rate either in cortical bone at the midshaft or in trabecular bone at the femoral neck on the stimulated side. However, maximum load and strain energy to failure were enhanced only by the random stimulation, on either the stimulated or non-stimulated side. It is concluded that randomized muscle stimulation has effective osteogenic capability at the stimulation site, similar to periodic stimulation; however, its effectiveness on mechanical properties is expandable to other non-stimulated sites.

  4. LTE-advanced random access mechanism for M2M communication: A review

    Science.gov (United States)

    Mustafa, Rashid; Sarowa, Sandeep; Jaglan, Reena Rathee; Khan, Mohammad Junaid; Agrawal, Sunil

    2016-03-01

    Machine Type Communications (MTC) enables one or more self-sufficient machines to communicate directly with one another without human interference. MTC applications include smart grid, security, e-Health and intelligent automation system. To support huge numbers of MTC devices, one of the challenging issues is to provide a competent way for numerous access in the network and to minimize network overload. In this article, the different control mechanisms for overload random access are reviewed to avoid congestion caused by random access channel (RACH) of MTC devices. However, past and present wireless technologies have been engineered for Human-to-Human (H2H) communications, in particular, for transmission of voice. Consequently the Long Term Evolution (LTE) -Advanced is expected to play a central role in communicating Machine to Machine (M2M) and are very optimistic about H2H communications. Distinct and unique characteristics of M2M communications create new challenges from those in H2H communications. In this article, we investigate the impact of massive M2M terminals attempting random access to LTE-Advanced all at once. We discuss and review the solutions to alleviate the overload problem by Third Generation Partnership Project (3GPP). As a result, we evaluate and compare these solutions that can effectively eliminate the congestion on the random access channel for M2M communications without affecting H2H communications.

  5. Forced Sequence Sequential Decoding

    DEFF Research Database (Denmark)

    Jensen, Ole Riis

    In this thesis we describe a new concatenated decoding scheme based on iterations between an inner sequentially decoded convolutional code of rate R=1/4 and memory M=23, and block interleaved outer Reed-Solomon codes with non-uniform profile. With this scheme decoding with good performance is pos...

  6. Forced Sequence Sequential Decoding

    DEFF Research Database (Denmark)

    Jensen, Ole Riis; Paaske, Erik

    1998-01-01

    We describe a new concatenated decoding scheme based on iterations between an inner sequentially decoded convolutional code of rate R=1/4 and memory M=23, and block interleaved outer Reed-Solomon (RS) codes with nonuniform profile. With this scheme decoding with good performance is possible as lo...

  7. Sequential memory: Binding dynamics

    Science.gov (United States)

    Afraimovich, Valentin; Gong, Xue; Rabinovich, Mikhail

    2015-10-01

    Temporal order memories are critical for everyday animal and human functioning. Experiments and our own experience show that the binding or association of various features of an event together and the maintaining of multimodality events in sequential order are the key components of any sequential memories—episodic, semantic, working, etc. We study a robustness of binding sequential dynamics based on our previously introduced model in the form of generalized Lotka-Volterra equations. In the phase space of the model, there exists a multi-dimensional binding heteroclinic network consisting of saddle equilibrium points and heteroclinic trajectories joining them. We prove here the robustness of the binding sequential dynamics, i.e., the feasibility phenomenon for coupled heteroclinic networks: for each collection of successive heteroclinic trajectories inside the unified networks, there is an open set of initial points such that the trajectory going through each of them follows the prescribed collection staying in a small neighborhood of it. We show also that the symbolic complexity function of the system restricted to this neighborhood is a polynomial of degree L - 1, where L is the number of modalities.

  8. Synthetic Aperture Sequential Beamforming

    DEFF Research Database (Denmark)

    Kortbek, Jacob; Jensen, Jørgen Arendt; Gammelmark, Kim Løkke

    2008-01-01

    A synthetic aperture focusing (SAF) technique denoted Synthetic Aperture Sequential Beamforming (SASB) suitable for 2D and 3D imaging is presented. The technique differ from prior art of SAF in the sense that SAF is performed on pre-beamformed data contrary to channel data. The objective is to im...

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

    Directory of Open Access Journals (Sweden)

    Raj Kumar Patel

    2016-09-01

    Full Text Available 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 statistical features and used as input feature for the classification problem. These features are classified through RF classifiers for four class problems. The prime objective of this paper is to evaluate effectiveness of random forest classifier on bearing fault diagnosis. The obtained results compared with the existing artificial intelligence techniques, neural network. The analysis of results shows the better performance and higher accuracy than the well existing techniques.

  10. Comment on: "Cell Therapy for Heart Disease: Trial Sequential Analyses of Two Cochrane Reviews"

    DEFF Research Database (Denmark)

    Castellini, Greta; Nielsen, Emil Eik; Gluud, Christian

    2017-01-01

    Trial Sequential Analysis is a frequentist method to help researchers control the risks of random errors in meta-analyses (1). Fisher and colleagues used Trial Sequential Analysis on cell therapy for heart diseases (2). The present article discusses the usefulness of Trial Sequential Analysis...

  11. Benefit and harm of adding ketamine to an opioid in a patient-controlled analgesia device for the control of postoperative pain: systematic review and meta-analyses of randomized controlled trials with trial sequential analyses.

    Science.gov (United States)

    Assouline, Benjamin; Tramèr, Martin R; Kreienbühl, Lukas; Elia, Nadia

    2016-12-01

    Ketamine is often added to opioids in patient-controlled analgesia devices. We tested whether in surgical patients, ketamine added to an opioid patient-controlled analgesia decreased pain intensity by ≥25%, cumulative opioid consumption by ≥30%, the risk of postoperative nausea and vomiting by ≥30%, the risk of respiratory adverse effects by ≥50%, and increased the risk of hallucination not more than 2-fold. In addition, we searched for evidence of dose-responsiveness. Nineteen randomized trials (1349 adults, 104 children) testing different ketamine regimens added to various opioids were identified through searches in databases and bibliographies (to 04.2016). In 9 trials (595 patients), pain intensity at rest at 24 hours was decreased by 32% with ketamine (weighted mean difference -1.1 cm on the 0-10 cm visual analog scale [98% CI, -1.8 to -0.39], P < 0.001). In 7 trials (495 patients), cumulative 24 hours morphine consumption was decreased by 28% with ketamine (weighted mean difference -12.9 mg [-22.4 to -3.35], P = 0.002). In 7 trials (435 patients), the incidence of postoperative nausea and vomiting was decreased by 44% with ketamine (risk ratio 0.56 [0.40 to 0.78], P < 0.001). There was no evidence of a difference in the incidence of respiratory adverse events (9 trials, 871 patients; risk ratio 0.31 [0.06 to 1.51], P = 0.08) or hallucination (7 trials, 690 patients; odds ratio 1.16 [0.47 to 2.79], P = 0.70). Trial sequential analyses confirmed the significant benefit of ketamine on pain intensity, cumulative morphine consumption, and postoperative nausea and vomiting and its inability to double the risk of hallucination. The available data did not allow us to make a conclusion on respiratory adverse events or to establish dose-responsiveness.

  12. A sequential tree approach for incremental sequential pattern mining

    Indian Academy of Sciences (India)

    Data mining; STISPM; sequential tree; incremental mining; backward tracking. Abstract. ''Sequential pattern mining'' is a prominent and significant method to explore the knowledge and innovation from the large database. Common sequential pattern mining algorithms handle static databases.Pragmatically, looking into the ...

  13. Random walks along the streets and canals in compact cities: Spectral analysis, dynamical modularity, information, and statistical mechanics

    Science.gov (United States)

    Volchenkov, D.; Blanchard, Ph.

    2007-02-01

    Different models of random walks on the dual graphs of compact urban structures are considered. Analysis of access times between streets helps to detect the city modularity. The statistical mechanics approach to the ensembles of lazy random walkers is developed. The complexity of city modularity can be measured by an informationlike parameter which plays the role of an individual fingerprint of Genius loci. Global structural properties of a city can be characterized by the thermodynamic parameters calculated in the random walk problem.

  14. Generation mechanism of nonlinear ultrasonic Lamb waves in thin plates with randomly distributed micro-cracks.

    Science.gov (United States)

    Zhao, Youxuan; Li, Feilong; Cao, Peng; Liu, Yaolu; Zhang, Jianyu; Fu, Shaoyun; Zhang, Jun; Hu, Ning

    2017-08-01

    Since the identification of micro-cracks in engineering materials is very valuable in understanding the initial and slight changes in mechanical properties of materials under complex working environments, numerical simulations on the propagation of the low frequency S 0 Lamb wave in thin plates with randomly distributed micro-cracks were performed to study the behavior of nonlinear Lamb waves. The results showed that while the influence of the randomly distributed micro-cracks on the phase velocity of the low frequency S 0 fundamental waves could be neglected, significant ultrasonic nonlinear effects caused by the randomly distributed micro-cracks was discovered, which mainly presented as a second harmonic generation. By using a Monte Carlo simulation method, we found that the acoustic nonlinear parameter increased linearly with the micro-crack density and the size of micro-crack zone, and it was also related to the excitation frequency and friction coefficient of the micro-crack surfaces. In addition, it was found that the nonlinear effect of waves reflected by the micro-cracks was more noticeable than that of the transmitted waves. This study theoretically reveals that the low frequency S 0 mode of Lamb waves can be used as the fundamental waves to quantitatively identify micro-cracks in thin plates. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Examination of mechanisms (E-MECHANIC) of exercise-induced weight compensation: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Myers, Candice A; Johnson, William D; Earnest, Conrad P; Rood, Jennifer C; Tudor-Locke, Catrine; Johannsen, Neil M; Cocreham, Shannon; Harris, Melissa; Church, Timothy S; Martin, Corby K

    2014-06-07

    Weight loss induced only by exercise is frequently less than expected, possibly because of compensatory changes in energy intake and/or energy expenditure. The purpose of the Examination of Mechanisms (E-MECHANIC) of Exercise-Induced Weight Compensation trial is to examine whether increased energy intake and/or reduced spontaneous activity or energy expenditure (outside of structured exercise) account for the less than expected, exercise-associated weight loss. E-MECHANIC is a three-arm, 6-month randomized (1:1:1) controlled trial. The two intervention arms are exercise doses that reflect current recommendations for (1) general health (8 kcal/kg body weight per week (8 KKW), about 900 kcal/wk) and (2) weight loss (20 KKW, about 2,250 kcal/wk). The third arm, a nonexercise control group, will receive health information only. The sample will include a combined total of 198sedentary, overweight or obese (body mass index: ≥25 kg/m² to ≤45 kg/m²) men and women ages 18 to 65 years. The exercise dose will be supervised and tightly controlled in an exercise training laboratory. The primary outcome variables are energy intake, which will be measured using doubly labeled water (adjusted for change in energy stores) and laboratory-based food intake tests, and the discrepancy between expected weight loss and observed weight loss. Secondary outcomes include changes in resting metabolic rate (adjusted for change in body mass), activity levels (excluding structured exercise) and body composition. In an effort to guide the development of future interventions, the participants will be behaviorally phenotyped and defined as those who do compensate (that is, fail to lose the amount of weight expected) or do not compensate (that is, lose the amount of weight expected or more). In this study, we will attempt to identify underlying mechanisms to explain why exercise elicits less weight loss than expected. This information will guide the development of interventions to increase

  16. Application of δ13C and δ15N isotopic signatures of organic matter fractions sequentially separated from adjacent arable and forest soils to identify carbon stabilization mechanisms

    Directory of Open Access Journals (Sweden)

    M. Sommer

    2011-10-01

    Full Text Available Identifying the chemical mechanisms behind soil carbon bound in organo-mineral complexes is necessary to determine the degree to which soil organic carbon is stabilized belowground. Analysis of δ13C and δ15N isotopic signatures of stabilized OM fractions along with soil mineral characteristics may yield important information about OM-mineral associations and their processing history. We anlayzed the δ13C and δ15N isotopic signatures from two organic matter (OM fractions along with soil mineral proxies to identify the likely binding mechanisms involved. We analyzed OM fractions hypothesized to contain carbon stabilized through organo-mineral complexes: (1 OM separated chemically with sodium pyrophosphate (OM(PY and (2 OM occluded in micro-structures found in the chemical extraction residue (OM(ER. Because the OM fractions were separated from five different soils with paired forest and arable land use histories, we could address the impact of land use change on carbon binding and processing mechanisms. We used partial least squares regression to analyze patterns in the isotopic signature of OM with established mineral and chemical proxies indicative for certain binding mechanisms. We found different mechanisms predominate in each land use type. For arable soils, the formation of OM(PY-Ca-mineral associations was identified as an important OM binding mechanism. Therefore, we hypothesize an increased stabilization of microbial processed OM(PY through Ca2+ interactions. In general, we found the forest soils to contain on average 10% more stabilized carbon relative to total carbon stocks, than the agricultural counter part. In forest soils, we found a positive relationship between isotopic signatures of OM(PY and the ratio of soil organic carbon content to soil surface area (SOC/SSA. This indicates that the OM(PY fractions of forest soils represent layers of slower exchange not directly attached to mineral surfaces. From the isotopic composition

  17. Investigating the effect of intra-operative infiltration with local anaesthesia on the development of chronic postoperative pain after inguinal hernia repair. A randomized placebo controlled triple blinded and group sequential study design [NCT00484731

    Directory of Open Access Journals (Sweden)

    Audigé Laurent

    2007-11-01

    Full Text Available Abstract Background Inguinal hernia repair is one of the most frequently performed procedures in Switzerland (15'000/year. The most common complication postoperatively is development of chronic pain in up to 30% of all patients irrespective of the operative technique. Methods/Design 264 patients scheduled for an inguinal hernia repair using one of three procedures (Lichtenstein, Barwell and TEP = total extraperitoneal hernioplasty are being randomly allocated intra-operatively into two groups. Group I patients receive a local injection of 20 ml Carbostesin® 0.25% at the end of the operation according to a standardised procedure. Group II patients get a 20 ml placebo (0.9% Saline injection. We use pre-filled identically looking syringes for blinded injection, i.e. the patient, the surgeon and the examinator who performs the postoperative clinical follow-ups remain unaware of group allocation. The primary outcome of the study is the occurrence of developing chronic pain (defined as persistent pain at 3 months FU measured by VAS and Pain Matcher® device (Cefar Medical AB, Lund, Sweden. The study started on July 2006. In addition to a sample size re-evaluation three interim analyses are planned after 120, 180 and 240 patients had finished their 3-months follow-up to allow for early study termination. Discussion Using a group sequential study design the minimum number of patients are enrolled to reach a valid conclusion before the end of the study. To limit subjectivity, both a VAS and the Pain Matcher® device are used for the evaluation of pain. This allows us also to compare these two methods and further assess the use of Pain Matcher® in clinical routine. The occurrence of chronic pain after inguinal hernia repair has been in focus of several clinical studies but the reduction of it has been rarely investigated. We hope to significantly reduce the occurrence of this complication with our investigated intervention. Trial Registration Our trial

  18. Platelet desialylation is a novel mechanism and a therapeutic target in thrombocytopenia during sepsis: an open-label, multicenter, randomized controlled trial.

    Science.gov (United States)

    Li, Mei-Feng; Li, Xiao-Li; Fan, Kai-Liang; Yu, Ying-Yi; Gong, Jing; Geng, Shu-Ying; Liang, Ya-Feng; Huang, Ling; Qiu, Ji-Hua; Tian, Xing-Han; Wang, Wen-Ting; Zhang, Xiao-Lu; Yu, Qing-Xia; Zhang, Yuan-Feng; Lin, Peng; Wang, Li-Na; Li, Xin; Hou, Ming; Liu, Lu-Yi; Peng, Jun

    2017-05-11

    Studies in murine models suggested that platelet desialylation was an important mechanism of thrombocytopenia during sepsis. First, we performed a prospective, multicenter, observational study that enrolled septic patients with or without thrombocytopenia to determine the association between platelet desialylation and thrombocytopenia in patients with sepsis, severe sepsis, and septic shock. Gender- and age-matched healthy adults were selected as normal controls in analysis of the platelet desialylation levels (study I). Next, we conducted an open-label randomized controlled trial (RCT) in which the patients who had severe sepsis with thrombocytopenia (platelet counts ≤50 × 10 9 /L) were randomly assigned to receive antimicrobial therapy alone (control group) or antimicrobial therapy plus oseltamivir (oseltamivir group) in a 1:1 ratio (study II). The primary outcomes were platelet desialylation level at study entry, overall platelet response rate within 14 days post-randomization, and all-cause mortality within 28 days post-randomization. Secondary outcomes included platelet recovery time, the occurrence of bleeding events, and the amount of platelets transfused within 14 days post-randomization. The platelet desialylation levels increased significantly in the 127 septic patients with thrombocytopenia compared to the 134 patients without thrombocytopenia. A platelet response was achieved in 45 of the 54 patients in the oseltamivir group (83.3%) compared with 34 of the 52 patients in the control group (65.4%; P = 0.045). The median platelet recovery time was 5 days (interquartile range 4-6) in the oseltamivir group compared with 7 days (interquartile range 5-10) in the control group (P = 0.003). The amount of platelets transfused decreased significantly in the oseltamivir group compared to the control group (P = 0.044). There was no difference in the overall 28-day mortality regardless of whether oseltamivir was used. The Sequential Organ

  19. Effect of Dexmedetomidine on Mortality and Ventilator-Free Days in Patients Requiring Mechanical Ventilation With Sepsis: A Randomized Clinical Trial.

    Science.gov (United States)

    Kawazoe, Yu; Miyamoto, Kyohei; Morimoto, Takeshi; Yamamoto, Tomonori; Fuke, Akihiro; Hashimoto, Atsunori; Koami, Hiroyuki; Beppu, Satoru; Katayama, Yoichi; Itoh, Makoto; Ohta, Yoshinori; Yamamura, Hitoshi

    2017-04-04

    Dexmedetomidine provides sedation for patients undergoing ventilation; however, its effects on mortality and ventilator-free days have not been well studied among patients with sepsis. To examine whether a sedation strategy with dexmedetomidine can improve clinical outcomes in patients with sepsis undergoing ventilation. Open-label, multicenter randomized clinical trial conducted at 8 intensive care units in Japan from February 2013 until January 2016 among 201 consecutive adult patients with sepsis requiring mechanical ventilation for at least 24 hours. Patients were randomized to receive either sedation with dexmedetomidine (n = 100) or sedation without dexmedetomidine (control group; n = 101). Other agents used in both groups were fentanyl, propofol, and midazolam. The co-primary outcomes were mortality and ventilator-free days (over a 28-day duration). Sequential Organ Failure Assessment score (days 1, 2, 4, 6, 8), sedation control, occurrence of delirium and coma, intensive care unit stay duration, renal function, inflammation, and nutrition state were assessed as secondary outcomes. Of the 203 screened patients, 201 were randomized. The mean age was 69 years (SD, 14 years); 63% were male. Mortality at 28 days was not significantly different in the dexmedetomidine group vs the control group (19 patients [22.8%] vs 28 patients [30.8%]; hazard ratio, 0.69; 95% CI, 0.38-1.22; P = .20). Ventilator-free days over 28 days were not significantly different between groups (dexmedetomidine group: median, 20 [interquartile range, 5-24] days; control group: median, 18 [interquartile range, 0.5-23] days; P = .20). The dexmedetomidine group had a significantly higher rate of well-controlled sedation during mechanical ventilation (range, 17%-58% vs 20%-39%; P = .01); other outcomes were not significantly different between groups. Adverse events occurred in 8 (8%) and 3 (3%) patients in the dexmedetomidine and control groups, respectively. Among patients

  20. The Statistical Mechanics of Random Set Packing and a Generalization of the Karp-Sipser Algorithm

    Directory of Open Access Journals (Sweden)

    C. Lucibello

    2014-01-01

    Full Text Available We analyse the asymptotic behaviour of random instances of the maximum set packing (MSP optimization problem, also known as maximum matching or maximum strong independent set on hypergraphs. We give an analytic prediction of the MSPs size using the 1RSB cavity method from statistical mechanics of disordered systems. We also propose a heuristic algorithm, a generalization of the celebrated Karp-Sipser one, which allows us to rigorously prove that the replica symmetric cavity method prediction is exact for certain problem ensembles and breaks down when a core survives the leaf removal process. The e-phenomena threshold discovered by Karp and Sipser, marking the onset of core emergence and of replica symmetry breaking, is elegantly generalized to Cs=e/(d-1 for one of the ensembles considered, where d is the size of the sets.

  1. Sequential Therapy with Minocycline and Candesartan Improves Long-Term Recovery After Experimental Stroke.

    Science.gov (United States)

    Soliman, Sahar; Ishrat, Tauheed; Fouda, Abdelrahman Y; Patel, Ami; Pillai, Bindu; Fagan, Susan C

    2015-08-01

    Minocycline and candesartan have both shown promise as candidate therapeutics in ischemic stroke, with multiple, and somewhat contrasting, molecular mechanisms. Minocycline is an anti-inflammatory, antioxidant, and anti-apoptotic agent and a known inhibitor of matrix metalloproteinases (MMPs). Yet, minocycline exerts antiangiogenic effects both in vivo and in vitro. Candesartan promotes angiogenesis and activates MMPs. Aligning these therapies with the dynamic processes of injury and repair after ischemia is likely to improve success of treatment. In this study, we hypothesize that opposing actions of minocycline and candesartan on angiogenesis, when administered simultaneously, will reduce the benefit of candesartan treatment. Therefore, we propose a sequential combination treatment regimen to yield a better outcome and preserve the proangiogenic potential of candesartan. In vitro angiogenesis was assessed using human brain endothelial cells. In vivo, Wistar rats subjected to 90-min middle cerebral artery occlusion (MCAO) were randomized into four groups: saline, candesartan, minocycline, and sequential combination of minocycline and candesartan. Neurobehavioral tests were performed 1, 3, 7, and 14 days after stroke. Brain tissue was collected on day 14 for assessment of infarct size and vascular density. Minocycline, when added simultaneously, decreased the proangiogenic effect of candesartan treatment in vitro. Sequential treatment, however, preserved the proangiogenic potential of candesartan both in vivo and in vitro, improved neurobehavioral outcome, and reduced infarct size. Sequential combination therapy with minocycline and candesartan improves long-term recovery and maintains candesartan's proangiogenic potential.

  2. Sequential Therapy with Minocycline and Candesartan Improves Long Term Recovery after Experimental Stroke

    Science.gov (United States)

    Soliman, Sahar; Ishrat, Tauheed; Fouda, Abdelrahman Y.; Patel, Ami; Pillai, Bindu; Fagan, Susan C.

    2015-01-01

    Background Minocycline and candesartan have both shown promise as candidate therapeutics in ischemic stroke, with multiple, and somewhat contrasting, molecular mechanisms. Minocycline is an anti-inflammatory, antioxidant and anti-apoptotic agent and a known inhibitor of matrix metalloproteinases (MMPs). Yet, minocycline exerts antiangiogenic effects both in vivo and in vitro. Candesartan promotes angiogenesis and activates MMPs. Aligning these therapies with the dynamic processes of injury and repair after ischemia is likely to improve success of treatment. Objective In this study, we hypothesize that opposing actions of minocycline and candesartan on angiogenesis, when administered simultaneously, will reduce the benefit of candesartan treatment. Therefore, we propose a sequential combination treatment regimen to yield a better outcome and preserve the proangiogenic potential of candesartan. Methods In vitro angiogenesis was assessed using human brain endothelial cells. In vivo, Wistar rats subjected to 90-minute middle cerebral artery occlusion (MCAO) were randomized into 4 groups: saline, candesartan, minocycline and sequential combination of minocycline and candesartan. Neurobehavioral tests were performed 1, 3, 7 and 14 days after stroke. Brain tissue was collected on day 14 for assessment of infarct size and vascular density. Results Minocycline, when added simultaneously, decreased the proangiogenic effect of candesartan treatment in vitro. Sequential treatment, however, preserved the proangiogenic potential of candesartan both in vivo and in vitro, improved neurobehavioral outcome and reduced infarct size. Conclusion Sequential combination therapy with minocycline and candesartan improves long term recovery and maintains candesartan’s proangiogenic potential. PMID:26004281

  3. Dexmedetomidine vs midazolam or propofol for sedation during prolonged mechanical ventilation: two randomized controlled trials.

    Science.gov (United States)

    Jakob, Stephan M; Ruokonen, Esko; Grounds, R Michael; Sarapohja, Toni; Garratt, Chris; Pocock, Stuart J; Bratty, J Raymond; Takala, Jukka

    2012-03-21

    Long-term sedation with midazolam or propofol in intensive care units (ICUs) has serious adverse effects. Dexmedetomidine, an α(2)-agonist available for ICU sedation, may reduce the duration of mechanical ventilation and enhance patient comfort. To determine the efficacy of dexmedetomidine vs midazolam or propofol (preferred usual care) in maintaining sedation; reducing duration of mechanical ventilation; and improving patients' interaction with nursing care. Two phase 3 multicenter, randomized, double-blind trials carried out from 2007 to 2010. The MIDEX trial compared midazolam with dexmedetomidine in ICUs of 44 centers in 9 European countries; the PRODEX trial compared propofol with dexmedetomidine in 31 centers in 6 European countries and 2 centers in Russia. Included were adult ICU patients receiving mechanical ventilation who needed light to moderate sedation for more than 24 hours (midazolam, n = 251, vs dexmedetomidine, n = 249; propofol, n = 247, vs dexmedetomidine, n = 251). Sedation with dexmedetomidine, midazolam, or propofol; daily sedation stops; and spontaneous breathing trials. For each trial, we tested whether dexmedetomidine was noninferior to control with respect to proportion of time at target sedation level (measured by Richmond Agitation-Sedation Scale) and superior to control with respect to duration of mechanical ventilation. Secondary end points were patients' ability to communicate pain (measured using a visual analogue scale [VAS]) and length of ICU stay. Time at target sedation was analyzed in per-protocol population (midazolam, n = 233, vs dexmedetomidine, n = 227; propofol, n = 214, vs dexmedetomidine, n = 223). Dexmedetomidine/midazolam ratio in time at target sedation was 1.07 (95% CI, 0.97-1.18) and dexmedetomidine/propofol, 1.00 (95% CI, 0.92-1.08). Median duration of mechanical ventilation appeared shorter with dexmedetomidine (123 hours [IQR, 67-337]) vs midazolam (164 hours [IQR, 92-380]; P = .03) but not with dexmedetomidine

  4. High-frequency chest wall oscillation in prolonged mechanical ventilation patients: a randomized controlled trial.

    Science.gov (United States)

    Huang, Wei-Chang; Wu, Pi-Chu; Chen, Chao-Jung; Cheng, Ya-Hua; Shih, Sou-Jen; Chen, Hui-Chen; Wu, Chieh-Liang

    2016-05-01

    Patients with prolonged mechanical ventilation (PMV) often retain airway secretions, which may be cleared with the assistance of high-frequency chest wall oscillation (HFCWO). This study aimed to determine the effectiveness, safety and tolerance/comfort of HFCWO after extubation in PMV patients. This parallel-designed, randomized controlled trial enrolled subjects with both intra-tracheal intubation and mechanical ventilator support continuously for at least 21 days between January 2011 and December 2012. Upon extubation, the participants were randomly assigned to either receive HFCWO for 5 days or not. The effectiveness [based on weaning success rates, daily clearance volume of sputum, serial changes in sputum coloration and chest X-ray (CXR) improvement rates], safety (by physiologic parameters) and tolerance/comfort [using the Modified Borg Scale (MBS) and Hamilton Anxiety Scale (HAS)] of HFCWO were investigated. There were 43 PMV subjects, including 23 in the HFCWO group and 20 in the non-HFCWO group. The weaning success rates were 82.6% (19/23) and 85% (17/20) in the HFCWO and non-HFCWO groups, respectively (P = 1.000). The HFCWO group had persistently greater numbers of daily sputum suctions and higher CXR improvement rates compared with the non-HFCWO group. There was significant sputum coloration lightening in the HFCWO group only. There was no significant difference in the MBS and HAS between the two groups and between pre- and post-HFCWO physiologic parameters. In PMV patients, HFCWO was safe, comfortable and effective in facilitating airway hygiene after removal of endotracheal tubes, but had no positive impact on weaning success. © 2014 John Wiley & Sons Ltd.

  5. Myofascial Release Therapy in the Treatment of Occupational Mechanical Neck Pain: A Randomized Parallel Group Study.

    Science.gov (United States)

    Rodríguez-Fuentes, Iván; De Toro, Francisco Javier; Rodríguez-Fuentes, Gustavo; de Oliveira, Iris Machado; Meijide-Faílde, Rosa; Fuentes-Boquete, Isaac Manuel

    2016-07-01

    As myofascial release therapy is currently under development, the objective of this study was to compare the effectiveness of myofascial release therapy with manual therapy for treating occupational mechanical neck pain. A randomized, single-blind parallel group study was developed. The sample (n = 59) was divided into GI, treated with manual therapy, and GII, treated with myofascial release therapy. Variables studied were intensity of neck pain, cervical disability, quality of life, craniovertebral angle, and ranges of cervical motion. At five sessions, clinical significance was observed in both groups for all the variables studied, except for flexion in GI. At this time point, an intergroup statistical difference was observed, which showed that GII had better craniovertebral angle (P = 0.014), flexion (P = 0.021), extension (P = 0.003), right side bending (P = 0.001), and right rotation (P = 0.031). A comparative analysis between therapies after intervention showed statistical differences indicating that GII had better craniovertebral angle (P = 0.000), right (P = 0.000) and left (P = 0.009) side bending, right (P = 0.024) and left (P = 0.046) rotations, and quality of life. The treatment of occupational mechanical neck pain by myofascial release therapy seems to be more effective than manual therapy for correcting the advanced position of the head, recovering range of motion in side bending and rotation, and improving quality of life.

  6. Products of sequentially pseudocompact spaces

    OpenAIRE

    Paolo Lipparini

    2012-01-01

    We show that the product of any number of sequentially pseudocompact topological spaces is still sequentially pseudocompact. The definition of sequential pseudocompactness can be given in (at least) two ways: we show their equivalence. Some of the results of the present note already appeared in A. Dow, J. R. Porter, R. M. Stephenson, R. G. Woods, Spaces whose pseudocompact subspaces are closed subsets, Appl. Gen. Topol. 5 (2004), 243-264.

  7. Physical and chemical mechanisms in oxide-based resistance random access memory.

    Science.gov (United States)

    Chang, Kuan-Chang; Chang, Ting-Chang; Tsai, Tsung-Ming; Zhang, Rui; Hung, Ya-Chi; Syu, Yong-En; Chang, Yao-Feng; Chen, Min-Chen; Chu, Tian-Jian; Chen, Hsin-Lu; Pan, Chih-Hung; Shih, Chih-Cheng; Zheng, Jin-Cheng; Sze, Simon M

    2015-01-01

    In this review, we provide an overview of our work in resistive switching mechanisms on oxide-based resistance random access memory (RRAM) devices. Based on the investigation of physical and chemical mechanisms, we focus on its materials, device structures, and treatment methods so as to provide an in-depth perspective of state-of-the-art oxide-based RRAM. The critical voltage and constant reaction energy properties were found, which can be used to prospectively modulate voltage and operation time to control RRAM device working performance and forecast material composition. The quantized switching phenomena in RRAM devices were demonstrated at ultra-cryogenic temperature (4K), which is attributed to the atomic-level reaction in metallic filament. In the aspect of chemical mechanisms, we use the Coulomb Faraday theorem to investigate the chemical reaction equations of RRAM for the first time. We can clearly observe that the first-order reaction series is the basis for chemical reaction during reset process in the study. Furthermore, the activation energy of chemical reactions can be extracted by changing temperature during the reset process, from which the oxygen ion reaction process can be found in the RRAM device. As for its materials, silicon oxide is compatible to semiconductor fabrication lines. It is especially promising for the silicon oxide-doped metal technology to be introduced into the industry. Based on that, double-ended graphene oxide-doped silicon oxide based via-structure RRAM with filament self-aligning formation, and self-current limiting operation ability is demonstrated. The outstanding device characteristics are attributed to the oxidation and reduction of graphene oxide flakes formed during the sputter process. Besides, we have also adopted a new concept of supercritical CO2 fluid treatment to efficiently reduce the operation current of RRAM devices for portable electronic applications.

  8. Chronic heart failure modifies respiratory mechanics in rats: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Deise M. Pacheco

    2016-01-01

    Full Text Available ABSTRACT Objective To analyze respiratory mechanics and hemodynamic alterations in an experimental model of chronic heart failure (CHF following myocardial infarction. Method Twenty-seven male adult Wistar rats were randomized to CHF group (n=12 or Sham group (n=15. Ten weeks after coronary ligation or sham surgery, the animals were anesthetized and submitted to respiratory mechanics and hemodynamic measurements. Pulmonary edema as well as cardiac remodeling were measured. Results The CHF rats showed pulmonary edema 26% higher than the Sham group. The respiratory system compliance (Crs and the total lung capacity (TLC were lower (40% and 27%, respectively in the CHF rats when compared to the Sham group (P<0.01. There was also an increase in tissue resistance (Gti and elastance (Hti (28% and 45%, respectively in the CHF group. Moreover, left ventricular end-diastolic pressure was higher (32 mmHg vs 4 mmHg, P<0.01, while the left ventricular systolic pressure was lower (118 mmHg vs 130 mmHg, P=0.02 in the CHF group when compared to the control. Pearson’s correlation coefficient showed a negative association between pulmonary edema and Crs (r=–0.70, P=0.0001 and between pulmonary edema and TLC (r=–0.67,P=0.0034. Pulmonary edema correlated positively with Gti (r=0.68, P=0.001 and Hti (r=0.68, P=0.001. Finally, there was a strong positive relationship between pulmonary edema and heart weight (r=0.80, P=0.001. Conclusion Rats with CHF present important changes in hemodynamic and respiratory mechanics, which may be associated with alterations in cardiopulmonary interactions.

  9. Info-Greedy Sequential Adaptive Compressed Sensing

    Science.gov (United States)

    Braun, Gabor; Pokutta, Sebastian; Xie, Yao

    2015-06-01

    We present an information-theoretic framework for sequential adaptive compressed sensing, Info-Greedy Sensing, where measurements are chosen to maximize the extracted information conditioned on the previous measurements. We show that the widely used bisection approach is Info-Greedy for a family of $k$-sparse signals by connecting compressed sensing and blackbox complexity of sequential query algorithms, and present Info-Greedy algorithms for Gaussian and Gaussian Mixture Model (GMM) signals, as well as ways to design sparse Info-Greedy measurements. Numerical examples demonstrate the good performance of the proposed algorithms using simulated and real data: Info-Greedy Sensing shows significant improvement over random projection for signals with sparse and low-rank covariance matrices, and adaptivity brings robustness when there is a mismatch between the assumed and the true distributions.

  10. Frequency of mechanical removal of plaque as it relates to gingival inflammation: a randomized clinical trial.

    Science.gov (United States)

    Pinto, Tatiana M P; de Freitas, Guilherme C; Dutra, Danilo A; Kantorski, Karla Z; Moreira, Carlos H

    2013-10-01

    This single blind, randomized clinical trial evaluated the relationship between frequency of mechanical removal of plaque (MRP) and gingival inflammation. Fifty-two patients (maximum 5% of sites with gingival bleeding and no history of periodontitis) were randomized to different frequencies of MRP: 12, 24, 48 and 72 h. Plaque index (PlI) and gingival index (GI) were evaluated at baseline, 15 and 30 days. Intra- and inter-group differences were determined by repeated measures anova and mixed models anova, respectively, both followed by Tukey's test. The mean GI between baseline and 30 days remained statistically unchanged in the 12 h (0.51 ± 0.17 versus 0.63 ± 0.23, p = 0.137) and 24 h (0.43 ± 0.19 versus 0.59 ± 0.21, p = 0.052) groups, but increased significantly in the 48 h (0.48 ± 0.18 versus 0.84 ± 0.21, p = 0.001) and 72 h (0.55 ± 0.20 versus 0.94 ± 0.25, p = 0.000) groups. At 30 days, the average percentage of sites with GI scores of 1 and 2 was significantly higher in the 48 and 72 h than in the 12 and 24 h groups (p plaque up to 24 h may prevent an increase in the severity of gingival inflammation over a period of 30 days in patients with no history of periodontitis. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Patient-oriented rehabilitation in the management of chronic mechanical neck pain: a randomized controlled trial.

    Science.gov (United States)

    Paoloni, M; Tavernese, E; Cacchio, A; Tattoli, M; Melis, L; Ronconi, R; Santilli, V

    2013-06-01

    Management of chronic mechanical neck pain (CMNP) still represents a challenge. A patient-oriented (Pa-O) therapeutic approach could be considered as the one in which therapies are scheduled at the start of each therapeutic session according to the patient's current physical status, and differs from a prescription-oriented (Pr-O) therapeutic approach, in which therapies are prescribed at the first medical referral and are not adjusted at any time during the treatment period. To determine if a Pa-O approach may be more beneficial for CMNP patients when compared to a Pr-O one. Randomized controlled trial. 220 CMNP outpatients randomized to either Pa-O group (N.=114) or Pr-O group (N.=106). Each group received 10 therapeutic sessions over 3 weeks. Primary outcome measures were pain assessment, evaluated by Visual-Analog-Scale (VAS), and disability level, evaluated by the Neck Pain and Disability Scale (NPDS-I). Secondary outcome measures included patients' response to treatment and treatment failures. Measurements were carried out at baseline (T0) and 1 month after treatment ended (T1). Data were analysed according to the intention-to-treat principle. Patients in both groups displayed at T1 a significant reduction in VAS and NPDS-I scores. The relative changes at T1 were greater in Pa-O group when compared with Pr-O group both for VAS (61.5% versus 48.8%; Pup in suffers from CMNP. However, the occurrence of a performance-bias due to the increased level of attention from physicians to patients in Pa-O group, cannot be ruled-out. A Pa-O approach should be considered for CMNP also in an outpatient facility.

  12. Initial combination therapy with metformin, pioglitazone and exenatide is more effective than sequential add-on therapy in subjects with new-onset diabetes. Results from the Efficacy and Durability of Initial Combination Therapy for Type 2 Diabetes (EDICT): a randomized trial.

    Science.gov (United States)

    Abdul-Ghani, M A; Puckett, C; Triplitt, C; Maggs, D; Adams, J; Cersosimo, E; DeFronzo, R A

    2015-03-01

    To test our hypothesis that initiating therapy with a combination of agents known to improve insulin secretion and insulin sensitivity in subjects with new-onset diabetes would produce greater, more durable reduction in glycated haemoglobin (HbA1c) levels, while avoiding hypoglycaemia and weight gain, compared with sequential addition of agents that lower plasma glucose but do not correct established pathophysiological abnormalities. Drug-naïve, recently diagnosed subjects with type 2 diabetes mellitus (T2DM) were randomized in an open-fashion design in a single-centre study to metformin/pioglitazone/exenatide (triple therapy; n = 106) or an escalating dose of metformin followed by sequential addition of sulfonylurea and glargine insulin (conventional therapy; n = 115) to maintain HbA1c levels at metformin/pioglitazone/exenatide in patients with newly diagnosed T2DM is more effective and results in fewer hypoglycaemic events than sequential add-on therapy with metformin, sulfonylurea and then basal insulin. © 2014 John Wiley & Sons Ltd.

  13. Multi-Attribute Sequential Search

    Science.gov (United States)

    Bearden, J. Neil; Connolly, Terry

    2007-01-01

    This article describes empirical and theoretical results from two multi-attribute sequential search tasks. In both tasks, the DM sequentially encounters options described by two attributes and must pay to learn the values of the attributes. In the "continuous" version of the task the DM learns the precise numerical value of an attribute when she…

  14. Mechanisms of skill in sequential motor behavior

    NARCIS (Netherlands)

    Verwey, W.B.

    1994-01-01

    The statement that practice is the major determinant of skilled behavior is a truism. Yet, it is unclear why practice is so important and what the consequences of practice are. This thesis addresses the theme of acquiring skill from a motor point of view: How is it possible that with practice more

  15. Sequential Design of Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Anderson-Cook, Christine Michaela [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-06-30

    A sequential design of experiments strategy is being developed and implemented that allows for adaptive learning based on incoming results as the experiment is being run. The plan is to incorporate these strategies for the NCCC and TCM experimental campaigns to be run in the coming months. This strategy for experimentation has the advantages of allowing new data collected during the experiment to inform future experimental runs based on their projected utility for a particular goal. For example, the current effort for the MEA capture system at NCCC plans to focus on maximally improving the quality of prediction of CO2 capture efficiency as measured by the width of the confidence interval for the underlying response surface that is modeled as a function of 1) Flue Gas Flowrate [1000-3000] kg/hr; 2) CO2 weight fraction [0.125-0.175]; 3) Lean solvent loading [0.1-0.3], and; 4) Lean solvent flowrate [3000-12000] kg/hr.

  16. [Effect of chest physiotherapy in patients undergoing mechanical ventilation: a prospective randomized controlled trial].

    Science.gov (United States)

    Zeng, Hui; Zhang, Zhen; Gong, Yuan; Chen, Miao

    2017-05-01

    To investigate the effect of chest physiotherapy (CPT) on patients undergoing mechanical ventilation (MV). A prospective randomized controlled trial (RCT) was conducted. Sixty-eight adult patients undergoing invasive MV over 48 hours admitted to intensive care unit (ICU) of Affiliated Hospital of Zunyi Medical College from December 2014 to October 2016 were enrolled, and they were divided into CPT group (n = 37) and control group (n = 31) by random number table. The patients in control group received routine physical therapy; while those in the CPT group received comprehensive CPT including manual lung inflation, vibration expectoration and early functional exercise etc. on the basis of the treatment in control group. Acute physiology and chronic health evaluation II (APACHE II) score and oxygenation index (PaO2/FiO2) before and after the treatment in both two groups were observed as well as the respiratory function and vital signs before and after CPT. The laboratory indicators after treatment, incidence of complications, duration of MV and the length of ICU stay in the two groups were recorded. The incidence of ventilator associated pneumonia (VAP) in the CPT group was significantly lower than that of control group (5.4% vs. 25.8%, P respiratory function parameters including tidal volume (VT), respiratory rate (RR), peak airway pressure (Ppeak) and mean airway pressure (Pmean) before and after treatment in CPT group excepting pulse oxygen saturation (SpO2) was significantly higher than that before treatment (0.985±0.016 vs. 0.978±0.018, P 2 0.05), indicating that CPT treatment did not cause fluctuations in respiratory function and vital signs. Blood lactate in CPT group was significantly lower than that of control group (mmol/L: 1.10±0.79 vs. 1.32±1.09, P < 0.05), indicating that CPT treatment, especially early functional exercise, could improve the oxygen supply and limb circulation. CPT treatment has some effect on prevention of VAP and other complications

  17. Sequential provisional implant prosthodontics therapy.

    Science.gov (United States)

    Zinner, Ira D; Markovits, Stanley; Jansen, Curtis E; Reid, Patrick E; Schnader, Yale E; Shapiro, Herbert J

    2012-01-01

    The fabrication and long-term use of first- and second-stage provisional implant prostheses is critical to create a favorable prognosis for function and esthetics of a fixed-implant supported prosthesis. The fixed metal and acrylic resin cemented first-stage prosthesis, as reviewed in Part I, is needed for prevention of adjacent and opposing tooth movement, pressure on the implant site as well as protection to avoid micromovement of the freshly placed implant body. The second-stage prosthesis, reviewed in Part II, should be used following implant uncovering and abutment installation. The patient wears this provisional prosthesis until maturation of the bone and healing of soft tissues. The second-stage provisional prosthesis is also a fail-safe mechanism for possible early implant failures and also can be used with late failures and/or for the necessity to repair the definitive prosthesis. In addition, the screw-retained provisional prosthesis is used if and when an implant requires removal or other implants are to be placed as in a sequential approach. The creation and use of both first- and second-stage provisional prostheses involve a restorative dentist, dental technician, surgeon, and patient to work as a team. If the dentist alone cannot do diagnosis and treatment planning, surgery, and laboratory techniques, he or she needs help by employing the expertise of a surgeon and a laboratory technician. This team approach is essential for optimum results.

  18. Statistical mechanics of random geometric graphs: Geometry-induced first-order phase transition.

    Science.gov (United States)

    Ostilli, Massimo; Bianconi, Ginestra

    2015-04-01

    Random geometric graphs (RGGs) can be formalized as hidden-variables models where the hidden variables are the coordinates of the nodes. Here we develop a general approach to extract the typical configurations of a generic hidden-variables model and apply the resulting equations to RGGs. For any RGG, defined through a rigid or a soft geometric rule, the method reduces to a nontrivial satisfaction problem: Given N nodes, a domain D, and a desired average connectivity 〈k〉, find, if any, the distribution of nodes having support in D and average connectivity 〈k〉. We find out that, in the thermodynamic limit, nodes are either uniformly distributed or highly condensed in a small region, the two regimes being separated by a first-order phase transition characterized by a O(N) jump of 〈k〉. Other intermediate values of 〈k〉 correspond to very rare graph realizations. The phase transition is observed as a function of a parameter a∈[0,1] that tunes the underlying geometry. In particular, a=1 indicates a rigid geometry where only close nodes are connected, while a=0 indicates a rigid antigeometry where only distant nodes are connected. Consistently, when a=1/2 there is no geometry and no phase transition. After discussing the numerical analysis, we provide a combinatorial argument to fully explain the mechanism inducing this phase transition and recognize it as an easy-hard-easy transition. Our result shows that, in general, ad hoc optimized networks can hardly be designed, unless to rely to specific heterogeneous constructions, not necessarily scale free.

  19. Cognitive bibliotherapy for mild depressive symptomatology: randomized clinical trial of efficacy and mechanisms of change.

    Science.gov (United States)

    Moldovan, Ramona; Cobeanu, Oana; David, Daniel

    2013-01-01

    It has been increasingly recognized that subthreshold depression is associated with considerable personal, social and economic costs. However, there is no accepted definition or clear-cut treatment for subthreshold depression. Cognitive bibliotherapy is a promising approach, but further research is necessary in order to assess its clinical efficacy and key mechanisms of change. This study aimed to investigate the efficacy of bibliotherapy for subthreshold depression and test whether maladaptive cognitions mediate the effects of bibliotherapy on depressive symptoms. A total of 96 young adults with subthreshold depression were randomized in one of the following treatment conditions: immediate treatment, delayed treatment, placebo and no treatment. The main outcome was represented by depressive symptoms assessed before, during and immediately after the treatment, as well as at 3-month follow-up. Automatic thoughts, dysfunctional attitudes and irrational beliefs were also assessed throughout the study, and we investigated their involvement as mediators of bibliotherapy effects on depressive symptoms. The results indicated that cognitive bibliotherapy resulted in statistically and clinically significant changes both in depressive symptoms and cognitions, which were maintained at follow-up. In contrast, placebo was only associated with a temporary decrease in depressive symptoms, without significant cognitive changes. No changes in symptoms or cognitions were found in the delayed treatment and no treatment groups. We also found that automatic thoughts significantly mediated the effect of bibliotherapy on depressive symptoms. This study provided compelling evidence for the efficacy of cognitive bibliotherapy in subthreshold depression and showed that changes in automatic thoughts mediated the effect of bibliotherapy on depressive symptoms. Cognitive bibliotherapy is an effective treatment of subthreshold depression. Changing automatic thoughts is important, as they

  20. Aerosol delivery with two ventilation modes during mechanical ventilation: a randomized study.

    Science.gov (United States)

    Dugernier, Jonathan; Reychler, Gregory; Wittebole, Xavier; Roeseler, Jean; Depoortere, Virginie; Sottiaux, Thierry; Michotte, Jean-Bernard; Vanbever, Rita; Dugernier, Thierry; Goffette, Pierre; Docquier, Marie-Agnes; Raftopoulos, Christian; Hantson, Philippe; Jamar, François; Laterre, Pierre-François

    2016-12-01

    Volume-controlled ventilation has been suggested to optimize lung deposition during nebulization although promoting spontaneous ventilation is targeted to avoid ventilator-induced diaphragmatic dysfunction. Comparing topographic aerosol lung deposition during volume-controlled ventilation and spontaneous ventilation in pressure support has never been performed. The aim of this study was to compare lung deposition of a radiolabeled aerosol generated with a vibrating-mesh nebulizer during invasive mechanical ventilation, with two modes: pressure support ventilation and volume-controlled ventilation. Seventeen postoperative neurosurgery patients without pulmonary disease were randomly ventilated in pressure support or volume-controlled ventilation. Diethylenetriaminepentaacetic acid labeled with technetium-99m (2 mCi/3 mL) was administrated using a vibrating-mesh nebulizer (Aerogen Solo(®), provided by Aerogen Ltd, Galway, Ireland) connected to the endotracheal tube. Pulmonary and extrapulmonary particles deposition was analyzed using planar scintigraphy. Lung deposition was 10.5 ± 3.0 and 15.1 ± 5.0 % of the nominal dose during pressure support and volume-controlled ventilation, respectively (p ventilation (27.4 ± 6.6 vs. 20.7 ± 6.0 %, p ventilation modes. A high intersubject variability of lung deposition was observed with both modes regarding lung doses, aerosol penetration and distribution between the right and the left lung. In the specific conditions of the study, volume-controlled ventilation was associated with higher lung deposition of nebulized particles as compared to pressure support ventilation. The clinical benefit of this effect warrants further studies. Clinical trial registration NCT01879488.

  1. Quantum epistemology from subquantum ontology: Quantum mechanics from theory of classical random fields

    Science.gov (United States)

    Khrennikov, Andrei

    2017-02-01

    The scientific methodology based on two descriptive levels, ontic (reality as it is) and epistemic (observational), is briefly presented. Following Schrödinger, we point to the possible gap between these two descriptions. Our main aim is to show that, although ontic entities may be unaccessible for observations, they can be useful for clarification of the physical nature of operational epistemic entities. We illustrate this thesis by the concrete example: starting with the concrete ontic model preceding quantum mechanics (the latter is treated as an epistemic model), namely, prequantum classical statistical field theory (PCSFT), we propose the natural physical interpretation for the basic quantum mechanical entity-the quantum state ("wave function"). The correspondence PCSFT ↦ QM is not straightforward, it couples the covariance operators of classical (prequantum) random fields with the quantum density operators. We use this correspondence to clarify the physical meaning of the pure quantum state and the superposition principle-by using the formalism of classical field correlations. In classical mechanics the phase space description can be considered as the ontic description, here states are given by points λ =(x , p) of phase space. The dynamics of the ontic state is given by the system of Hamiltonian equations.We can also consider probability distributions on the phase space (or equivalently random variables valued in it). We call them probabilistic ontic states. Dynamics of probabilistic ontic states is given by the Liouville equation.In classical physics we can (at least in principle) measure both the coordinate and momentum and hence ontic states can be treated as epistemic states as well (or it is better to say that here epistemic states can be treated as ontic states). Probabilistic ontic states represent probabilities for outcomes of joint measurement of position and momentum.However, this was a very special, although very important, example of

  2. The impact of daily evaluation and spontaneous breathing test on the duration of pediatric mechanical ventilation: a randomized controlled trial.

    Science.gov (United States)

    Foronda, Flávia K; Troster, Eduardo J; Farias, Julio A; Barbas, Carmen S; Ferraro, Alexandre A; Faria, Lucília S; Bousso, Albert; Panico, Flávia F; Delgado, Artur F

    2011-11-01

    To assess whether the combination of daily evaluation and use of a spontaneous breathing test could shorten the duration of mechanical ventilation as compared with weaning based on our standard of care. Secondary outcome measures included extubation failure rate and the need for noninvasive ventilation. A prospective, randomized controlled trial. Two pediatric intensive care units at university hospitals in Brazil. The trial involved children between 28 days and 15 yrs of age who were receiving mechanical ventilation for at least 24 hrs. Patients were randomly assigned to one of two weaning protocols. In the test group, the children underwent a daily evaluation to check readiness for weaning with a spontaneous breathing test with 10 cm H2O pressure support and a positive end-expiratory pressure of 5 cm H2O for 2 hrs. The spontaneous breathing test was repeated the next day for children who failed it. In the control group, weaning was performed according to standard care procedures. A total of 294 eligible children were randomized, with 155 to the test group and 139 to the control group. The time to extubation was shorter in the test group, where the median mechanical ventilation duration was 3.5 days (95% confidence interval, 3.0 to 4.0) as compared to 4.7 days (95% confidence interval, 4.1 to 5.3) in the control group (p = .0127). This significant reduction in the mechanical ventilation duration for the intervention group was not associated with increased rates of extubation failure or noninvasive ventilation. It represents a 30% reduction in the risk of remaining on mechanical ventilation (hazard ratio: 0.70). A daily evaluation to check readiness for weaning combined with a spontaneous breathing test reduced the mechanical ventilation duration for children on mechanical ventilation for >24 hrs, without increasing the extubation failure rate or the need for noninvasive ventilation.

  3. DNA Sequential Logic Gate Using Two-Ring DNA.

    Science.gov (United States)

    Zhang, Cheng; Shen, Linjing; Liang, Chao; Dong, Yafei; Yang, Jing; Xu, Jin

    2016-04-13

    Sequential DNA detection is a fundamental issue for elucidating the interactive relationships among complex gene systems. Here, a sequential logic DNA gate was achieved by utilizing the two-ring DNA structure, with the ability to recognize "before" and "after" triggering sequences of DNA signals. By taking advantage of a "loop-open" mechanism, separations of two-ring DNAs were controlled. Three triggering pathways with different sequential DNA treatments were distinguished by comparing fluorescent outputs. Programmed nanoparticle arrangement guided by "interlocked" two-ring DNA was also constructed to demonstrate the achievement of designed nanostrucutres. Such sequential logic DNA operation may guide future molecular sensors to monitor more complex gene network in biological systems.

  4. Quantum Mechanical Enhancement of the Random Dopant Induced Threshold Voltage Fluctuations and Lowering in Sub 0.1 Micron MOSFETs

    Science.gov (United States)

    Asenov, Asen; Slavcheva, G.; Brown, A. R.; Davies, J. H.; Saini, Subhash

    1999-01-01

    A detailed study of the influence of quantum effects in the inversion layer on the random dopant induced threshold voltage fluctuations and lowering in sub 0.1 micron MOSFETs has been performed. This has been achieved using a full 3D implementation of the density gradient (DG) formalism incorporated in our previously published 3D 'atomistic' simulation approach. This results in a consistent, fully 3D, quantum mechanical picture which implies not only the vertical inversion layer quantisation but also the lateral confinement effects manifested by current filamentation in the 'valleys' of the random potential fluctuations. We have shown that the net result of including quantum mechanical effects, while considering statistical fluctuations, is an increase in both threshold voltage fluctuations and lowering.

  5. Music preferences of mechanically ventilated patients participating in a randomized controlled trial

    OpenAIRE

    Heiderscheit, Annie; Breckenridge, Stephanie J.; Chlan, Linda L.; Savik, Kay

    2014-01-01

    Mechanical ventilation (MV) is a life-saving measure and supportive modality utilized to treat patients experiencing respiratory failure. Patients experience pain, discomfort, and anxiety as a result of being mechanically ventilated. Music listening is a non-pharmacological intervention used to manage these psychophysiological symptoms associated with mechanical ventilation.

  6. Different strategies for mechanical VENTilation during CardioPulmonary Bypass (CPBVENT 2014): study protocol for a randomized controlled trial.

    Science.gov (United States)

    Bignami, Elena; Guarnieri, Marcello; Saglietti, Francesco; Maglioni, Enivarco Massimo; Scolletta, Sabino; Romagnoli, Stefano; De Paulis, Stefano; Paternoster, Gianluca; Trumello, Cinzia; Meroni, Roberta; Scognamiglio, Antonio; Budillon, Alessandro Maria; Pota, Vincenzo; Zangrillo, Alberto; Alfieri, Ottavio

    2017-06-07

    There is no consensus on which lung-protective strategies should be used in cardiac surgery patients. Sparse and small randomized clinical and animal trials suggest that maintaining mechanical ventilation during cardiopulmonary bypass is protective on the lungs. Unfortunately, such evidence is weak as it comes from surrogate and minor clinical endpoints mainly limited to elective coronary surgery. According to the available data in the academic literature, an unquestionable standardized strategy of lung protection during cardiopulmonary bypass cannot be recommended. The purpose of the CPBVENT study is to investigate the effectiveness of different strategies of mechanical ventilation during cardiopulmonary bypass on postoperative pulmonary function and complications. The CPBVENT study is a single-blind, multicenter, randomized controlled trial. We are going to enroll 870 patients undergoing elective cardiac surgery with planned use of cardiopulmonary bypass. Patients will be randomized into three groups: (1) no mechanical ventilation during cardiopulmonary bypass, (2) continuous positive airway pressure of 5 cmH2O during cardiopulmonary bypass, (3) respiratory rate of 5 acts/min with a tidal volume of 2-3 ml/Kg of ideal body weight and positive end-expiratory pressure of 3-5 cmH2O during cardiopulmonary bypass. The primary endpoint will be the incidence of a PaO2/FiO2 ratio bypass will have an impact on postoperative pulmonary complications and outcomes of patients undergoing cardiac surgery. ClinicalTrials.gov, ID: NCT02090205 . Registered on 8 March 2014.

  7. 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…

  8. The Progression of Sequential Reactions

    Directory of Open Access Journals (Sweden)

    Jack McGeachy

    2010-01-01

    Full Text Available Sequential reactions consist of linked reactions in which the product of the first reaction becomes the substrate of a second reaction. Sequential reactions occur in industrially important processes, such as the chlorination of methane. A generalized series of three sequential reactions was analyzed in order to determine the times at which each chemical species reaches its maximum. To determine the concentration of each species as a function of time, the differential rate laws for each species were solved. The solution of each gave the concentration curve of the chemical species. The concentration curves of species A1 and A2 possessed discreet maxima, which were determined through slope-analysis. The concentration curve of the final product, A3, did not possess a discreet maximum, but rather approached a finite limit.

  9. Morphological and mechanical analyses of laminates manufactured from randomly positioned carbon fibre/epoxy resin prepreg scraps

    Science.gov (United States)

    Souza, Christiane S. R.; Cândido, Geraldo M.; Alves, Wellington; Marlet, José Maria F.; Rezende, Mirabel C.

    2017-10-01

    This study aims to contribute to sustainability by proposing the reuse of composite prepreg scrap as an added value from discards. The research evaluates the microstructure and mechanical properties of laminates processed by the reuse of uncured carbon fibre/F155-epoxy resin prepreg scraps, waste from the ply cutting area of an aeronautical industry. The composite scraps were used as collected and were randomly positioned to produce laminates to be cured at an autoclave. The mechanical characterization shows a decrease of 39% for the compression property due to the discontinuous fibres in the laminate and an increase of 34% for the interlaminar shear strength, when compared to continuous fibre laminates. This increase is attributed to the higher crosslink density of the epoxy resin, as a result of the cure temperature used in autoclave (60 °C higher than suggested by supplier) and also to the randomly positioned scraps. Microscopic analyses confirm the consolidation of laminates, although show resin rich areas with different sizes and shapes attributed to the overlapping of the scraps with different sizes and shapes. These resin rich areas may contribute to decrease the mechanical properties of laminates. The correlation between mechanical and morphological results shows potential to be used on non-critical structural application, as composite jigs, contributing to sustainability.

  10. Sequential Divestiture and Firm Asymmetry

    Directory of Open Access Journals (Sweden)

    Wen Zhou

    2013-01-01

    Full Text Available Simple Cournot models of divestiture tend to generate incentives to divest which are too strong, predicting that firms will break up into an infinite number of divisions resulting in perfect competition. This paper shows that if the order of divestitures is endogenized, firms will always choose sequential, and hence very limited, divestitures. Divestitures favor the larger firm and the follower in a sequential game. Divestitures in which the larger firm is the follower generate greater industry profit and social welfare, but a smaller consumer surplus.

  11. Sequential versus simultaneous market delineation

    DEFF Research Database (Denmark)

    Haldrup, Niels; Møllgaard, Peter; Kastberg Nielsen, Claus

    2005-01-01

    and geographical markets. Using a unique data setfor prices of Norwegian and Scottish salmon, we propose a methodologyfor simultaneous market delineation and we demonstrate that comparedto a sequential approach conclusions will be reversed.JEL: C3, K21, L41, Q22Keywords: Relevant market, econometric delineation......Delineation of the relevant market forms a pivotal part of most antitrustcases. The standard approach is sequential. First the product marketis delineated, then the geographical market is defined. Demand andsupply substitution in both the product dimension and the geographicaldimension...

  12. Non Random Distribution of DMD Deletion Breakpoints and Implication of Double Strand Breaks Repair and Replication Error Repair Mechanisms.

    Science.gov (United States)

    Marey, Isabelle; Ben Yaou, Rabah; Deburgrave, Nathalie; Vasson, Aurélie; Nectoux, Juliette; Leturcq, France; Eymard, Bruno; Laforet, Pascal; Behin, Anthony; Stojkovic, Tanya; Mayer, Michèle; Tiffreau, Vincent; Desguerre, Isabelle; Boyer, François Constant; Nadaj-Pakleza, Aleksandra; Ferrer, Xavier; Wahbi, Karim; Becane, Henri-Marc; Claustres, Mireille; Chelly, Jamel; Cossee, Mireille

    2016-05-27

    Dystrophinopathies are mostly caused by copy number variations, especially deletions, in the dystrophin gene (DMD). Despite the large size of the gene, deletions do not occur randomly but mainly in two hot spots, the main one involving exons 45 to 55. The underlying mechanisms are complex and implicate two main mechanisms: Non-homologous end joining (NHEJ) and micro-homology mediated replication-dependent recombination (MMRDR). Our goals were to assess the distribution of intronic breakpoints (BPs) in the genomic sequence of the main hot spot of deletions within DMD gene and to search for specific sequences at or near to BPs that might promote BP occurrence or be associated with DNA break repair. Using comparative genomic hybridization microarray, 57 deletions within the intron 44 to 55 region were mapped. Moreover, 21 junction fragments were sequenced to search for specific sequences. Non-randomly distributed BPs were found in introns 44, 47, 48, 49 and 53 and 50% of BPs clustered within genomic regions of less than 700bp. Repeated elements (REs), known to promote gene rearrangement via several mechanisms, were present in the vicinity of 90% of clustered BPs and less frequently (72%) close to scattered BPs, illustrating the important role of such elements in the occurrence of DMD deletions. Palindromic and TTTAAA sequences, which also promote DNA instability, were identified at fragment junctions in 20% and 5% of cases, respectively. Micro-homologies (76%) and insertions or deletions of small sequences were frequently found at BP junctions. Our results illustrate, in a large series of patients, the important role of RE and other genomic features in DNA breaks, and the involvement of different mechanisms in DMD gene deletions: Mainly replication error repair mechanisms, but also NHEJ and potentially aberrant firing of replication origins. A combination of these mechanisms may also be possible.

  13. One-Dimensional Disordered Quantum Mechanics and Sinai Diffusion with Random Absorbers

    Science.gov (United States)

    Grabsch, Aurélien; Texier, Christophe; Tourigny, Yves

    2014-04-01

    We study the one-dimensional Schrödinger equation with a disordered potential of the form where is a Gaussian white noise with mean and variance , and is a random superposition of delta functions distributed uniformly on the real line with mean density and mean strength . Our study is motivated by the close connection between this problem and classical diffusion in a random environment (the Sinai problem) in the presence of random absorbers: models the force field acting on the diffusing particle and models the absorption properties of the medium in which the diffusion takes place. The focus is on the calculation of the complex Lyapunov exponent , where is the integrated density of states per unit length and the reciprocal of the localisation length. By using the continuous version of the Dyson-Schmidt method, we find an exact formula, in terms of a Hankel function, in the particular case where the strength of the delta functions is exponentially-distributed with mean . Building on this result, we then solve the general case— in the low-energy limit— in terms of an infinite sum of Hankel functions. Our main result, valid without restrictions on the parameters of the model, is that the integrated density of states exhibits the power law behaviour This confirms and extends several results obtained previously by approximate methods.

  14. [Timing of tracheotomy on the prognosis of patients with prolonged mechanical ventilation: a meta-analysis of randomized controlled trials].

    Science.gov (United States)

    Lu, Yuan-hua; Qiu, Xiao-Hua; Guo, Feng-mei; Yang, Yi; Qiu, Hai-bo

    2011-02-01

    To evaluate the effect of timing of tracheotomy on the prognosis of prolonged mechanically ventilated patients. Randomized controlled trials (RCTs) that studied the effect of timing of tracheotomy on the prognosis of prolonged mechanically ventilated patients were searched from Pubmed, Embase, The Cochrane Library, CBM during January 1990 to June 2010. The quality of the RCTs was evaluated. Meta-analysis of timing of tracheotomy on the prognosis of prolonged mechanically ventilated patients were conducted using the methods recommended by the Cochrane Collaboration. Definition of early tracheotomy was the patients performed tracheotomy during 10 days after admission to hospital or ICU, mechanical ventilation or intubation. Late tracheotomy was defined tracheotomy performed beyond 10 days of admission to hospital or ICU, mechanical ventilation or intubation; or those mechanically ventilated through intubation all the time. Eight hundred and twenty eight patients, 411 in early tracheotomy group and 417 in late tracheotomy group, from 6 RCTs were included in the analysis of data. The meta-analysis showed that early tracheotomy could reduce mortality of patients (RR: 0.81, 95%CI: 0.66 - 0.99, P = 0.04); but it didn't significantly alter the incidence of pneumonia (RR:0.89, 95%CI: 0.68 - 1.17, P = 0.41), mechanical ventilation days (mean difference: -2.19, 95%CI: -9.86 - 5.49, P = 0.58) and length of ICU stay (mean difference: -5.65, 95%CI: -17.11 - 5.81, P = 0.33). In critically ill adult patients who require prolonged mechanical ventilation, early tracheotomy performed at an earlier stage reduces the mortality, but doesn't reduce the incidence of pneumonia and shorten the mechanical ventilation days and ICU length of stay. But more high quality RCTs are required to confirm it.

  15. Attack Trees with Sequential Conjunction

    NARCIS (Netherlands)

    Jhawar, Ravi; Kordy, Barbara; Mauw, Sjouke; Radomirović, Sasa; Trujillo-Rasua, Rolando

    2015-01-01

    We provide the first formal foundation of SAND attack trees which are a popular extension of the well-known attack trees. The SAND at- tack tree formalism increases the expressivity of attack trees by intro- ducing the sequential conjunctive operator SAND. This operator enables the modeling of

  16. Structure and mechanical properties of supramolecular random copolymer hydrogels cross linked by hydrophobic aggregates.

    Science.gov (United States)

    Vogt, Bryan; Wiener, Clinton; Wang, Chao; Weiss, Bob

    Stress dissipation mechanisms are critical to improving the toughness of hydrogels. The use of reversible hydrophobic associations for crosslnking of hydrogels provides such a mechanism for toughening, but can also lead to the creep of the hydrogel as the crosslinks break and reform. The morphology of the hydrophobic aggregates thus is critical to the mechanical properties of the hydrogels. In this work, we will demonstrate how the processing of these copolymers impacts the hydrogel structure and this structure is correlated with the mechanical properties through a combination of small angle scattering, rheology, and tensile measurements. The hydrophilic and hydrophobic chemistries in the copolymer can be used to tune the water content and strength of the crosslinks, while the copolymer composition provides the number density of crosslinks and also acts to modulate the swelling of the hydrogel. These copolymers as well as their hydrogels can in general use traditional polymer processing, but the details of this processing impacts both the nanoscale morphology and the resultant mechanical properties of the hydrogels. This work was financially supported by the Civil, Mechanical and Manufacturing Innovation (CMMI) Division in the Directorate for Engineering of the National Science Foundation, Grant. CMMI-1300212.

  17. Investigating neural mechanisms of change of cognitive behavioural therapy for chronic fatigue syndrome: a randomized controlled trial.

    Science.gov (United States)

    van Der Schaaf, Marieke E; Schmits, Iris C; Roerink, Megan; Geurts, Dirk E M; Toni, Ivan; Roelofs, Karin; De Lange, Floris P; Nater, Urs M; van der Meer, Jos W M; Knoop, Hans

    2015-07-03

    Chronic fatigue syndrome (CFS) is characterized by profound and disabling fatigue with no known somatic explanation. Cognitive behavioral therapy (CBT) has proven to be a successful intervention leading to a reduction in fatigue and disability. Based on previous neuroimaging findings, it has been suggested that central neural mechanisms may underlie CFS symptoms and play a role in the change brought on by CBT. In this randomized controlled trial we aim to further investigate the neural mechanisms that underlie fatigue in CFS and their change by CBT. We will conduct a randomized controlled trial in which we collect anatomical and functional magnetic resonance imaging (MRI) measures from female CFS patients before and after CBT (N = 60) or waiting list (N = 30) and compare these with measures from age and education matched healthy controls (N = 30). By including a large treatment group we will also be able to compare patients that benefit from CBT with those that do not. In addition, to further investigate the role of endocrine and immune biomarkers in CFS, we will determine cortisol and cytokine concentrations in blood, hair and/or saliva. This project creates an unique opportunity to enhance our understanding of CFS symptoms and its change by CBT in terms of neuroanatomical, neurofunctional, endocrinological and immunological mechanisms and can help to further improve future treatments strategies. Dutch Trial Register #15852. Registered 9 December 2013 ( http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=4311 ).

  18. Variable versus conventional lung protective mechanical ventilation during open abdominal surgery: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Spieth, Peter M; Güldner, Andreas; Uhlig, Christopher; Bluth, Thomas; Kiss, Thomas; Schultz, Marcus J; Pelosi, Paolo; Koch, Thea; Gama de Abreu, Marcelo

    2014-05-02

    General anesthesia usually requires mechanical ventilation, which is traditionally accomplished with constant tidal volumes in volume- or pressure-controlled modes. Experimental studies suggest that the use of variable tidal volumes (variable ventilation) recruits lung tissue, improves pulmonary function and reduces systemic inflammatory response. However, it is currently not known whether patients undergoing open abdominal surgery might benefit from intraoperative variable ventilation. The PROtective VARiable ventilation trial ('PROVAR') is a single center, randomized controlled trial enrolling 50 patients who are planning for open abdominal surgery expected to last longer than 3 hours. PROVAR compares conventional (non-variable) lung protective ventilation (CV) with variable lung protective ventilation (VV) regarding pulmonary function and inflammatory response. The primary endpoint of the study is the forced vital capacity on the first postoperative day. Secondary endpoints include further lung function tests, plasma cytokine levels, spatial distribution of ventilation assessed by means of electrical impedance tomography and postoperative pulmonary complications. We hypothesize that VV improves lung function and reduces systemic inflammatory response compared to CV in patients receiving mechanical ventilation during general anesthesia for open abdominal surgery longer than 3 hours. PROVAR is the first randomized controlled trial aiming at intra- and postoperative effects of VV on lung function. This study may help to define the role of VV during general anesthesia requiring mechanical ventilation. Clinicaltrials.gov NCT01683578 (registered on September 3 3012).

  19. eLearning course may shorten the duration of mechanical restraint among psychiatric inpatients: a cluster-randomized trial.

    Science.gov (United States)

    Kontio, Raija; Pitkänen, Anneli; Joffe, Grigori; Katajisto, Jouko; Välimäki, Maritta

    2014-10-01

    The management of psychiatric inpatients exhibiting severely disturbed and aggressive behaviour is an important educational topic. Well structured, IT-based educational programmes (eLearning) often ensure quality and may make training more affordable and accessible. The aim of this study was to explore the impact of an eLearning course for personnel on the rates and duration of seclusion and mechanical restraint among psychiatric inpatients. In a cluster-randomized intervention trial, the nursing personnel on 10 wards were randomly assigned to eLearning (intervention) or training-as-usual (control) groups. The eLearning course comprised six modules with specific topics (legal and ethical issues, behaviour-related factors, therapeutic relationship and self-awareness, teamwork and integrating knowledge with practice) and specific learning methods. The rates (incidents per 1000 occupied bed days) and durations of the coercion incidents were examined before and after the course. A total of 1283 coercion incidents (1143 seclusions [89%] and 140 incidents involving the use of mechanical restraints [11%]) were recorded on the study wards during the data collection period. On the intervention wards, there were no statistically significant changes in the rates of seclusion and mechanical restraint. However, the duration of incidents involving mechanical restraints shortened from 36.0 to 4.0 h (median) (P eLearning course, the duration of incidents involving the use of mechanical restraints decreased. However, more studies are needed to ensure that the content of the course focuses on the most important factors associated with the seclusion-related elements. The eLearning course deserves further development and further studies. The duration of coercion incidents merits attention in future research.

  20. Efficacy of respiratory muscle training in weaning of mechanical ventilation in patients with mechanical ventilation for 48hours or more: A Randomized Controlled Clinical Trial.

    Science.gov (United States)

    Sandoval Moreno, L M; Casas Quiroga, I C; Wilches Luna, E C; García, A F

    2018-02-02

    To evaluate the efficacy of respiratory muscular training in the weaning of mechanical ventilation and respiratory muscle strength in patients on mechanical ventilation of 48hours or more. Randomized controlled trial of parallel groups, double-blind. Ambit: Intensive Care Unit of a IV level clinic in the city of Cali. 126 patients in mechanical ventilation for 48hours or more. The experimental group received daily a respiratory muscle training program with treshold, adjusted to 50% of maximal inspiratory pressure, additional to standard care, conventional received standard care of respiratory physiotherapy. MAIN INTEREST VARIABLES: weaning of mechanical ventilation. Other variables evaluated: respiratory muscle strength, requirement of non-invasive mechanical ventilation and frequency of reintubation. intention-to-treat analysis was performed with all variables evaluated and analysis stratified by sepsis condition. There were no statistically significant differences in the median weaning time of the MV between the groups or in the probability of extubation between groups (HR: 0.82 95% CI: 0.55-1.20 P=.29). The maximum inspiratory pressure was increased in the experimental group on average 9.43 (17.48) cmsH20 and in the conventional 5.92 (11.90) cmsH20 (P=.48). The difference between the means of change in maximal inspiratory pressure was 0.46 (P=.83 95%CI -3.85 to -4.78). respiratory muscle training did not demonstrate efficacy in the reduction of the weaning period of mechanical ventilation nor in the increase of respiratory muscle strength in the study population. Registered study at ClinicalTrials.gov (NCT02469064). Copyright © 2017 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

  1. The Effectiveness of Mechanical Traction Among Subgroups of Patients With Low Back Pain and Leg Pain: A Randomized Trial.

    Science.gov (United States)

    Thackeray, Anne; Fritz, Julie M; Childs, John D; Brennan, Gerard P

    2016-03-01

    Randomized clinical trial. Background The recommended initial management strategy for patients with low back pain and signs of nerve root compression is conservative treatment, but there is little evidence to guide the most appropriate management strategy. Preliminary research suggests that a treatment protocol of mechanical traction and extension-oriented exercises may be effective, particularly in a specific subgroup of patients. To examine the effectiveness of mechanical traction in patients with lumbar nerve root compression and within a predefined subgroup. One hundred twenty patients with low back pain with nerve root compression were recruited from physical therapy clinics. Using predefined subgrouping criteria, patients were stratified at baseline and randomized to receive an extension-oriented treatment approach with or without the addition of mechanical traction. During a 6-week period, patients received up to 12 treatment visits. Primary outcomes of pain and disability were collected at 6 weeks, 6 months, and 1 year by assessors blinded to group allocation. Outcomes were examined using linear mixed-model analyses examining change over time by treatment and the interaction between treatment and subgrouping status. The mean ± SD age of participants was 41.1 ± 11.3 years, median duration of symptoms was 62 days, and 57% were male. No significant differences in disability or pain outcomes were noted between treatment groups at any time point, nor was any interaction found between subgroup status and treatment. Patients with lumbar nerve root compression presenting for physical therapy can expect significant changes in disability and pain over a 6-week treatment period. There is no evidence that mechanical lumbar traction in combination with an extension-oriented treatment is superior to extension-oriented exercises alone in the management of these patients or within a predefined subgroup of patients. The study protocol was registered with Clinical

  2. A particle swarm optimization algorithm with random learning mechanism and Levy flight for optimization of atomic clusters

    Science.gov (United States)

    Yan, Bailu; Zhao, Zheng; Zhou, Yingcheng; Yuan, Wenyan; Li, Jian; Wu, Jun; Cheng, Daojian

    2017-10-01

    Swarm intelligence optimization algorithms are mainstream algorithms for solving complex optimization problems. Among these algorithms, the particle swarm optimization (PSO) algorithm has the advantages of fast computation speed and few parameters. However, PSO is prone to premature convergence. To solve this problem, we develop a new PSO algorithm (RPSOLF) by combining the characteristics of random learning mechanism and Levy flight. The RPSOLF algorithm increases the diversity of the population by learning from random particles and random walks in Levy flight. On the one hand, we carry out a large number of numerical experiments on benchmark test functions, and compare these results with the PSO algorithm with Levy flight (PSOLF) algorithm and other PSO variants in previous reports. The results show that the optimal solution can be found faster and more efficiently by the RPSOLF algorithm. On the other hand, the RPSOLF algorithm can also be applied to optimize the Lennard-Jones clusters, and the results indicate that the algorithm obtains the optimal structure (2-60 atoms) with an extraordinary high efficiency. In summary, RPSOLF algorithm proposed in our paper is proved to be an extremely effective tool for global optimization.

  3. Suboptimal feedback control of TCP flows in computer network using random early discard (RED mechanism

    Directory of Open Access Journals (Sweden)

    Ahmed N. U.

    2005-01-01

    Full Text Available We consider a dynamic model that simulates the interaction of TCP sources with active queue management system (AQM. We propose a modified version of an earlier dynamic model called RED. This is governed by a system of stochastic differential equations driven by a doubly stochastic point process with intensity as the control. The feedback control law proposed observes the router (queue status and controls the intensity by sending congestion signals (warnings to the sources for adjustment of their transmission rates. The (feedback control laws used are of polynomial type (including linear with adjustable coefficients. They are optimized by use of genetic algorithm (GA and random recursive search (RRS technique. The numerical results demonstrate that the proposed model and the method can improve the system performance significantly.

  4. Manual Cardiopulmonary Resuscitation Versus CPR Including a Mechanical Chest Compression Device in Out-of-Hospital Cardiac Arrest: A Comprehensive Meta-analysis From Randomized and Observational Studies

    NARCIS (Netherlands)

    Bonnes, J.L.; Brouwer, M.A.; Navarese, E.P.; Verhaert, D.V.; Verheugt, F.W.; Smeets, J.L.; Boer, M.J. de

    2016-01-01

    STUDY OBJECTIVE: Mechanical chest compression devices have been developed to facilitate continuous delivery of high-quality cardiopulmonary resuscitation (CPR). Despite promising hemodynamic data, evidence on clinical outcomes remains inconclusive. With the completion of 3 randomized controlled

  5. Randomized controlled clinical trial of long-term chemo-mechanical caries removal using PapacarieTM gel

    Directory of Open Access Journals (Sweden)

    Lara Jansiski MOTTA

    2014-07-01

    Full Text Available Objectives: Compare the effectiveness of PapacarieTM gel for the chemo-mechanical removal of carious lesions on primary teeth to conventional caries removal with a low-speed bur with regard to execution time, clinical aspects and radiographic findings. Material and Methods: A randomized controlled clinical trial with a split-mouth design was carried out. The sample was composed of 20 children aged four to seven years, in whom 40 deciduous teeth were randomly divided into two groups: chemo-mechanical caries removal with PapacarieTM and removal of carious dentin with a low-speed bur. Each child underwent both procedures and served as his/her own control. Restorations were performed with glass ionomer cement. The time required to perform the procedure was also analyzed. The patients underwent longitudinal clinical and radiographic follow-up of the restorations. Results: No statistically significant difference between groups was found regarding the time required to perform the procedures and the radiographic follow up. Statistically significant differences between groups were found in the clinical evaluation at 6 and 18 months after treatment. Conclusion: PapacarieTM is as effective as the traditional method for the removal of carious dentin on deciduous teeth, but offers the advantages of the preservation of sound dental tissue as well as the avoidance of sharp rotary instruments and local anesthesia.

  6. Isotope partitioning for NAD-malic enzyme from Ascaris suum confirms a steady-state random kinetic mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Chen, C.Y.; Harris, B.G.; Cook, P.F.

    1988-01-12

    Isotope partitioning studies beginning with E-(/sup 14/C)NAD, E-(/sup 14/C) malate, E-(/sup 14/C) NAD-Mg/sup 2 +/, and E-Mg-(/sup 14/C)malate suggest a steady-state random mechanism for the NAD-malic enzyme. Isotope trapping beginning with E-(/sup 14/C)NAD and with varying concentrations of Mg/sup 2 +/ and malate in the chase solution indicates that Mg/sup 2 +/ is added in rapid equilibrium and must be added prior to malate for productive ternary complex formation. Equal percentage trapping from E-(/sup 14/C)NAD-Mg and E-Mg-(/sup 14/C) malate indicates the mechanism is steady-state random with equal off-rates for NAD and malate from E-NAD-Mg-malate. The off-rates for both do not change significantly in the ternary E-Mg-malate and E-NAD-Mg complexes, nor does the off-rate change for NAD from E-NAD. No trapping of malate was obtained from E-(/sup 14/C) malate, suggesting that this complex is nonproductive. A quantitative analysis of the data allows an estimation of values for a number of the rate constants along the reaction pathway.

  7. Sequential Treatment of Severe Postmenopausal Osteoporosis Following Teriparatide: Final Results of the Randomized, Controlled European Study of Forsteo (EUROFORS): Trial registration: clinicaltrials.gov identifier NCT00191425 (Trial registration date: 12 September 2005)

    DEFF Research Database (Denmark)

    Eastell, Richard; Nickelsen, Thomas; Marin, Fernando

    2009-01-01

    .5% with teriparatide, 2.3% with raloxifene, and 0.5% with no active treatment; the respective changes at the femoral neck were 3.5%, 3.1%, and 1.3%. The study had insufficient power to assess antifracture efficacy. In conclusion, BMD increases progressively over 2 yr of teriparatide therapy in women with severe......, antiresorptive with raloxifene, or no active treatment) after 1 yr of teriparatide. Postmenopausal women with osteoporosis and a recent fragility fracture received open-label teriparatide (20 mug/d) for 12 mo before they were randomized (3:1:1) to continue teriparatide (n=305), switch to raloxifene 60 mg/d (n...

  8. Nonlocality in sequential correlation scenarios

    Science.gov (United States)

    Gallego, Rodrigo; Würflinger, Lars Erik; Chaves, Rafael; Acín, Antonio; Navascués, Miguel

    2014-03-01

    As first shown by Popescu (1995 Phys. Rev. Lett. 74 2619), some quantum states only reveal their nonlocality when subjected to a sequence of measurements while giving rise to local correlations in standard Bell tests. Motivated by this manifestation of ‘hidden nonlocality’ we set out to develop a general framework for the study of nonlocality when sequences of measurements are performed. Similar to Gallego et al (2013 Phys. Rev. Lett. 109 070401) our approach is operational, i.e. the task is to identify the set of allowed operations in sequential correlation scenarios and define nonlocality as the resource that cannot be created by these operations. This leads to a characterization of sequential nonlocality that contains as particular cases standard nonlocality and hidden nonlocality.

  9. Influence of Mechanical Ventilation on the Incidence of Pneumothorax During Infraclavicular Subclavian Vein Catheterization: A Prospective Randomized Noninferiority Trial.

    Science.gov (United States)

    Kim, Eugene; Kim, Hyun Joo; Hong, Deok Man; Park, Hee-Pyoung; Bahk, Jae-Hyon

    2016-09-01

    It remains unclear whether we have to interrupt mechanical ventilation during infraclavicular subclavian venous catheterization. In practice, the clinicians' choice about lung deflation depends on their own discretion. The purpose of this study was to assess the influence of mechanical ventilation on the incidence of pneumothorax during infraclavicular subclavian venous catheterization. A total of 332 patients, who needed subclavian venous catheterization, were randomly assigned to 1 of the 2 groups: catheterizations were performed with the patients' lungs under mechanical ventilation (ventilation group, n = 165) or without mechanical ventilation (deflation group, n = 167). The incidences of pneumothorax and other complications such as arterial puncture, hemothorax, or catheter misplacements and the success rate of catheterization were compared. The incidences of pneumothorax were 0% (0/165) in the ventilation group and 0.6% (1/167) in the deflation group. The incidence of pneumothorax in the deflation group was 0.6% higher than that in the ventilation group and the 2-sided 90% confidence interval for the difference was (-1.29% to 3.44%). Because the lower bound for the 2-sided 90% confidence interval, -1.29%, was higher than the predefined noninferiority margin of -3%, the inferiority of the ventilation group over the deflation group was rejected at the .05 level of significance. Other complication rates and success rates of catheterization were comparable between 2 groups. The oxygen saturation dropped below 95% in 9 patients in the deflation group, while none in the ventilation group (P = .007). The success and complication rates were similar regardless of mechanical ventilation. During infraclavicular subclavian venous catheterization, interruption of mechanical ventilation does not seem to be necessary for the prevention of pneumothorax.

  10. A randomized trial of protocol-directed sedation management for mechanical ventilation in an Australian intensive care unit.

    Science.gov (United States)

    Bucknall, Tracey K; Manias, Elizabeth; Presneill, Jeffrey J

    2008-05-01

    To compare protocol-directed sedation management with traditional non-protocol-directed practice in mechanically ventilated patients. Randomized, controlled trial. General intensive care unit (24 beds) in an Australian metropolitan teaching hospital. Adult, mechanically ventilated patients (n = 312). Patients were randomly assigned to receive sedation directed by formal guidelines (protocol group, n = 153) or usual local clinical practice (control, n = 159). The median (95% confidence interval) duration of ventilation was 79 hrs (56-93 hrs) for patients in the protocol group compared with 58 hrs (44-78 hrs) for patients who received control care (p = .20). Lengths of stay (median [range]) in the intensive care unit (94 [2-1106] hrs vs. 88 (14-962) hrs, p = .58) and hospital (13 [1-113] days vs. 13 (1-365) days, p = .97) were similar, as were the proportions of subjects receiving a tracheostomy (17% vs. 15%, p = .64) or undergoing unplanned self-extubation (1.3% vs. 0.6%, p = .61). Death in the intensive care unit occurred in 32 (21%) patients in the protocol group and 32 (20%) control subjects (p = .89), with a similar overall proportion of deaths in hospital (25% vs. 22%, p = .51). A Cox proportional hazards model, after adjustment for age, gender, Acute Physiology and Chronic Health Evaluation II score, diagnostic category, and doses of commonly used drugs, estimated that protocol sedation management was associated with a 22% decrease (95% confidence interval 40% decrease to 2% increase, p = .07) in the occurrence of successful weaning from mechanical ventilation. This randomized trial provided no evidence of a substantial reduction in the duration of mechanical ventilation or length of stay, in either the intensive care unit or the hospital, with the use of protocol-directed sedation compared with usual local management. Qualified high-intensity nurse staffing and routine Australian intensive care unit nursing responsibility for many aspects of ventilatory

  11. Sequential probability ratio tests based on grouped observations

    OpenAIRE

    Eger, Karl-Heinz; Tsoy, Evgeni Borisovich

    2010-01-01

    This paper deals with sequential likelihood ratio tests based on grouped observations. It is demonstrated that the method of conjugated parameter pairs known from the non-grouped case can be extended to the grouped case obtaining Waldlike approximations for the OC- and ASN- function. For near hypotheses so-called F-optimal groupings are recommended. As example an SPRT based on grouped observations for the parameter of an exponentially distributed random var...

  12. The effect of a sequential structure of practice for the training of perceptual-cognitive skills in tennis.

    Directory of Open Access Journals (Sweden)

    David P Broadbent

    Full Text Available Anticipation of opponent actions, through the use of advanced (i.e., pre-event kinematic information, can be trained using video-based temporal occlusion. Typically, this involves isolated opponent skills/shots presented as trials in a random order. However, two different areas of research concerning representative task design and contextual (non-kinematic information, suggest this structure of practice restricts expert performance. The aim of this study was to examine the effect of a sequential structure of practice during video-based training of anticipatory behavior in tennis, as well as the transfer of these skills to the performance environment.In a pre-practice-retention-transfer design, participants viewed life-sized video of tennis rallies across practice in either a sequential order (sequential group, in which participants were exposed to opponent skills/shots in the order they occur in the sport, or a non-sequential (non-sequential group random order.In the video-based retention test, the sequential group was significantly more accurate in their anticipatory judgments when the retention condition replicated the sequential structure compared to the non-sequential group. In the non-sequential retention condition, the non-sequential group was more accurate than the sequential group. In the field-based transfer test, overall decision time was significantly faster in the sequential group compared to the non-sequential group.Findings highlight the benefits of a sequential structure of practice for the transfer of anticipatory behavior in tennis. We discuss the role of contextual information, and the importance of representative task design, for the testing and training of perceptual-cognitive skills in sport.

  13. AREVA: multicenter randomized comparison of low-dose versus standard-dose anticoagulation in patients with mechanical prosthetic heart valves.

    Science.gov (United States)

    Acar, J; Iung, B; Boissel, J P; Samama, M M; Michel, P L; Teppe, J P; Pony, J C; Breton, H L; Thomas, D; Isnard, R; de Gevigney, G; Viguier, E; Sfihi, A; Hanania, G; Ghannem, M; Mirode, A; Nemoz, C

    1996-11-01

    Moderate anticoagulation may be proposed to reduce the risk of hemorrhage for certain patients with a mechanical prosthesis, but the consequences for risk of thromboembolism are debated. The purpose of the AREVA trial was to compare moderate oral anticoagulation (international normalized ratio [INR] of 2.0 to 3.0) with the usual regimen (INR of 3.0 to 4.5) after a single-valve replacement with a mechanical prosthesis, either Omnicarbon or St Jude. Patients included were between 18 and 75 years old, in sinus rhythm, and with a left atrial diameter < or = 50 mm on the time-motion echocardiogram. Patients were randomized for INR after surgery. From 1991 to 1994, 433 patients underwent valve replacement (aortic, 414; mitral, 19) with 353 St Jude and 80 Omnicarbon prostheses; 380 patients were randomized for INR: 188 for INR 2.0 to 3.0 and 192 for INR 3.0 to 4.5. Mean follow-up was 2.2 years (1 to 4 years). Analysis of 18001 INR samples showed that the mean of the median of INR was 2.74 +/- 0.35 in the 2.0 to 3.0 group and 3.21 +/- 0.33 in the 3.0 to 4.5 group (P < .0001). Thromboembolic events, as assessed from clinical data and CT brain scans, occurred in 10 patients in the 2.0 to 3.0 INR group and 9 patients in the 3.0 to 4.5 INR group (P = .78). Hemorrhagic events occurred in 34 patients in the 2.0 to 3.0 INR group and 56 patients in the 3.0 to 4.5 INR group (P < .01), with 13 and 19 major hemorrhagic events, respectively (P = .29). In selected patients with mechanical prostheses, moderate anticoagulation prevents thromboembolic events as effectively as conventional anticoagulation and reduces the incidence of hemorrhagic events.

  14. Evaluation of the Effect of Nebulized N-Acetylcysteine on Respiratory Secretions in Mechanically Ventilated Patients: Randomized Clinical Trial

    Directory of Open Access Journals (Sweden)

    Seyed Masoom Masoompour

    2015-07-01

    Full Text Available Background: The purpose of our study was to evaluate an inexpensive and available method to reduce mucous impactions in mechanically ventilated patients. Methods: This randomized clinical trial was conducted on 40 mechanically ventilated patients aged 15-90 years. The patients were randomly allocated into two arms; 20 cases and 20 controls. The cases received N-acetylcysteine via their nebulizers, and the control group received normal saline three times a day for one day. We measured the density of respiratory secretion, plateau and peak airway pressures, and O2 saturation at baseline, 12 and 24 hours later. Results: Although the mean secretion density was significantly lower in the NAC group (F (1, 38=8.61, P=0.006, but a repeated measures ANOVA with a Greenhouse-Geisser correction determined that the effect of NAC on mean secretion density did not differ significantly between time points (F (1, 38=3.08, P=0.087. NAC increased O2 saturation significantly between time points (F (1.92, 73.1=4.6, P=0.014. The plateau airway pressures were relatively stable throughout the study in the normal saline and NAC groups (F (1.95, 37.1=0.67, P=0.513. The peak airway pressure did not change significantly during the study in the normal saline and NAC groups (F (1.52, 56.4=0.91, P=0.384. Conclusion: Considering the limitations of the study, nebulized NAC in mechanically ventilated patients was not effective more than normal saline nebulization in reducing the density of mucous plugs. The peak and plateau airway pressures were relatively stable throughout the study in both groups. Trial Registration Number: IRCT201104276312N1.

  15. Comparison of mechanical and femtosecond laser tunnel creation for intrastromal corneal ring segment implantation in keratoconus: prospective randomized clinical trial.

    Science.gov (United States)

    Kubaloglu, Anil; Sari, Esin Sogutlu; Cinar, Yasin; Cingu, Kürşat; Koytak, Arif; Coşkun, Erol; Ozertürk, Yusuf

    2010-09-01

    To compare the outcomes of mechanical and femtosecond laser-assisted tunnel creation for intrastromal corneal ring segment (ICRS) implantation in eyes with keratoconus. Kartal Training and Research Hospital, Istanbul, Turkey. In this prospective study, consecutive eyes with keratoconus were randomly assigned to have ICRS tunnel creation with a mechanical device or a femtosecond laser. Keraring ICRS with a 5.0 mm diameter and 160-degree arc length were implanted in all cases. The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, and keratometry (K) readings were measured preoperatively and 1 year postoperatively, and the data in the mechanical group and the femtosecond group were compared statistically. One year postoperatively, there was significant improvement in UDVA, CDVA, K readings, spherical equivalent (SE), and manifest sphere and cylinder in both groups (Pmechanical group and 2.0 lines in the femtosecond group and the CDVA by 3.3 lines and 2.7 lines, respectively; the mean reduction in maximum keratometry was 4.50 diopters (D) and 4.70 D, respectively, and the mean reduction in SE, 3.18 D and 3.09 D, respectively. There were no statistically significant differences between the 2 groups in visual or refractive results (P>.05). Anterior corneal perforation, superficial segment placement, and segment extrusion occurred in 1 eye each in the mechanical group. Segment migration occurred in 1 eye in the femtosecond group. Despite intraoperative complications in the mechanical group, the visual and refractive outcomes were similar to those in the femtosecond group. Copyright (c) 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  16. Managerial adjustment and its limits: sequential fault in comparative perspective

    Directory of Open Access Journals (Sweden)

    Flávio da Cunha Rezende

    2008-01-01

    Full Text Available This article focuses on explanations for sequential faults in administrative reform. It deals with the limits of managerial adjustment in an approach that attempts to connect theory and empirical data, articulating three levels of analysis. The first level presents comparative evidence of sequential fault within reforms in national governments through a set of indicators geared toward understanding changes in the role of the state. In light of analyses of a representative set of comparative studies on reform implementation, the second analytical level proceeds to identify four typical mechanisms that are present in explanations on managerial adjustment faults. In this way, we seek to configure an explanatory matrix for theories on sequential fault. Next we discuss the experience of management reform in the Brazilian context, conferring special attention on one of the mechanisms that creates fault: the control dilemma. The major hypotheses that guide our article are that reforms lead to sequential fault and that there are at least four causal mechanisms that produce reforms: a transactions costs involved in producing reforms; b performance legacy; c predominance of fiscal adjustment and d the control dilemma. These mechanisms act separately or in concert, and act to decrease chances for a transformation of State managerial patterns. Major evidence that is analyzed in these articles lend consistency to the general argument that reforms have failed in their attempts to reduce public expenses, alter patterns of resource allocation, reduce the labor force and change the role of the State. Our major conclusion is that reforms fail sequentially and managerial adjustment displays considerable limitations, particularly those of a political nature.

  17. Cognitive processes associated with sequential tool use in New Caledonian crows.

    Science.gov (United States)

    Wimpenny, Joanna H; Weir, Alex A S; Clayton, Lisa; Rutz, Christian; Kacelnik, Alex

    2009-08-05

    Using tools to act on non-food objects--for example, to make other tools--is considered to be a hallmark of human intelligence, and may have been a crucial step in our evolution. One form of this behaviour, 'sequential tool use', has been observed in a number of non-human primates and even in one bird, the New Caledonian crow (Corvus moneduloides). While sequential tool use has often been interpreted as evidence for advanced cognitive abilities, such as planning and analogical reasoning, the behaviour itself can be underpinned by a range of different cognitive mechanisms, which have never been explicitly examined. Here, we present experiments that not only demonstrate new tool-using capabilities in New Caledonian crows, but allow examination of the extent to which crows understand the physical interactions involved. In two experiments, we tested seven captive New Caledonian crows in six tasks requiring the use of up to three different tools in a sequence to retrieve food. Our study incorporated several novel features: (i) we tested crows on a three-tool problem (subjects were required to use a tool to retrieve a second tool, then use the second tool to retrieve a third one, and finally use the third one to reach for food); (ii) we presented tasks of different complexity in random rather than progressive order; (iii) we included a number of control conditions to test whether tool retrieval was goal-directed; and (iv) we manipulated the subjects' pre-testing experience. Five subjects successfully used tools in a sequence (four from their first trial), and four subjects repeatedly solved the three-tool condition. Sequential tool use did not require, but was enhanced by, pre-training on each element in the sequence ('chaining'), an explanation that could not be ruled out in earlier studies. By analyzing tool choice, tool swapping and improvement over time, we show that successful subjects did not use a random probing strategy. However, we find no firm evidence to

  18. Hydrogen-dependent low frequency noise and its physical mechanism of HfO2 resistance change random access memory

    Science.gov (United States)

    Chen, Y. Q.; Liu, X.; Liu, Y.; Peng, C.; Fang, W. X.; En, Y. F.; Huang, Y.

    2017-12-01

    The effect of hydrogen on low frequency noise characteristics of HfO2 resistance change random access memories (RRAMs) was investigated in this paper. The experimental results show that HfO2 RRAMs after hydrogen treatment take on the better uniformity of switch characteristics and the conduction enhancement behavior. Furthermore, it was found that the low frequency noise characteristics of the HfO2 RRAMs was significantly impacted by the hydrogen treatment, and at three kinds of typical resistance states, the low frequency noises of the HfO2 RRAMs after hydrogen treatment are larger than those of the fresh HfO2 RRAMs. The mechanism could be attributed to H induced oxygen vacancies, which serve as the additional traps for conduction due to the trap-assisted tunneling process. This will result in more random trap/detrap processes in the conducting filament, which gives rise to the larger low frequency noise in the HfO2 RRAMs. The results of this study may be useful in the design and application of HfO2 RRAMs.

  19. Lumbar lordosis rehabilitation for pain and lumbar segmental motion in chronic mechanical low back pain: a randomized trial.

    Science.gov (United States)

    Diab, Aliaa A; Moustafa, Ibrahim M

    2012-05-01

    The purpose of this study was to investigate the effects of lumbar extension traction with stretching and infrared radiation compared with stretching and infrared radiation alone on the lumbar curve, pain, and intervertebral movements of patients with chronic mechanical low back pain (CMLBP). This randomized clinical study with 3-month follow-up was completed at the Cairo University research laboratory. Eighty patients (age ranged from 40 to 50 years) with CMLBP and a hypolordotic lumbar spine were randomly assigned to traction or a comparison group. The comparison group (n = 40) received stretching exercises and infrared radiation, whereas the traction group (n = 40) received lumbar extension traction in addition to stretching exercises and infrared radiation. The absolute rotatory angle, intervertebral movements, and visual analog scale were measured for all patients at 3 intervals. The results revealed a statistically significant difference between the groups at 2 follow-up time points compared with the baseline values for the translational and sagittal rotational movements of L3-L4, L4-L5, L5-S1, and L2-L3 (posttreatment) and absolute rotatory angle (P .01). Lumbar extension traction with stretching exercises and infrared radiation was superior to stretching exercises and infrared radiation alone for improving the sagittal lumbar curve, pain, and intervertebral movement in CMLBP. Copyright © 2012 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

  20. Which neural mechanisms mediate the effects of a parenting intervention program on parenting behavior: design of a randomized controlled trial.

    Science.gov (United States)

    Kolijn, Laura; Euser, Saskia; van den Bulk, Bianca G; Huffmeijer, Renske; van IJzendoorn, Marinus H; Bakermans-Kranenburg, Marian J

    2017-03-21

    The Video-feedback Intervention to promote Positive Parenting and Sensitive Discipline (VIPP-SD) has proven effective in increasing parental sensitivity. However, the mechanisms involved are largely unknown. In a randomized controlled trial we examine parental neurocognitive factors that may mediate the intervention effects on parenting behavior. Our aims are to (1) examine whether the intervention influences parents' neural processing of children's emotional expressions and the neural precursors of response inhibition and to (2) test whether neural changes mediate intervention effects on parenting behavior. We will test 100 mothers of 4-6 year old same-sex twins. A random half of the mothers will receive the VIPP-SD Twins (i.e. VIPP-SD adapted for twin families), consisting of 5 home visits in a 3-months period; the other half will receive a dummy intervention. Neurocognitive measures are acquired approximately 2 weeks before and 2 weeks after the intervention. Mothers' electroencephalographic (EEG) activity is measured while performing a stop signal task and in response to children's facial expressions. To obtain a complementary behavioral measure, mothers also perform an emotion recognition task. Parenting behavior will be assessed during parent-child interactions at pre and post intervention lab visits. Our results will shed light on the neurocognitive factors underlying changes in parenting behavior after a parenting support program, which may benefit the development of such programs. Dutch Trial Register: NTR5312 ; Date registered: January 3, 2017.

  1. Trial sequential analysis reveals insufficient information size and potentially false positive results in many meta-analyses

    DEFF Research Database (Denmark)

    Brok, Jesper; Thorlund, Kristian; Gluud, Christian

    2008-01-01

    To evaluate meta-analyses with trial sequential analysis (TSA). TSA adjusts for random error risk and provides the required number of participants (information size) in a meta-analysis. Meta-analyses not reaching information size are analyzed with trial sequential monitoring boundaries analogous...

  2. High frequency oscillatory ventilation versus conventional mechanical ventilation in pediatric acute respiratory distress syndrome: A randomized controlled study.

    Science.gov (United States)

    El-Nawawy, Ahmed; Moustafa, Azza; Heshmat, Hassan; Abouahmed, Ahmed

    2017-01-01

    El-Nawawy A, Moustafa A, Heshmat H, Abouahmed A. High frequency oscillatory ventilation versus conventional mechanical ventilation in pediatric acute respiratory distress syndrome: A randomized controlled study. Turk J Pediatr 2017; 59: 130-143. The aim of this prospective randomized study is to compare the outcomes of the early use of either high frequency oscillation (HFO) or conventional mechanical ventilation (CMV) in patients with pediatric acute respiratory distress syndrome (PARDS). We allocated two hundred PARDS patients over 5 years in 1:1 ratio to either mode. The HFO group showed a significantly higher median partial arterial oxygen pressure to fraction of inspired oxygen (PaO2/FiO2) values after 24 hours of enrollment (p=0.011), higher oxygenation index (OI) decrease percent (p=0.004) and lower cross-over rates (p ventilation days (p=0.77, p=0.28, p=0.65 respectively). The second day values (after 24 hours) of both OI and PaO 2 /FiO 2 were found to be more significant discriminators for mortality when compared to the baseline values (cutoff values > 8.5, ≤139 respectively). PARDS patients with baseline OI > 16 had a better chance of survival if initially ventilated with the HFO (p=0.004). Although the HFO mode appeared to be a safe mode with a significant better oxygenation improvement (after the first 24 hours) and fewer cross-over rates, it failed to show differences as regards mortality or LOS when compared to the CMV adopting protective lung strategy. In PARDS, HFO had a superior advantage in improving oxygenation, yet with no significant mortality improvement, as multi-organ dysfunction syndrome (MODS) was the most common cause of death in our study and not refractory hypoxemia which is the main problem in PARDS; highlighting that mortality in PARDS is multi-factorial and may not depend only on how fast oxygenation improves.

  3. Effectiveness of dry needling on the lower trapezius in patients with mechanical neck pain: a randomized controlled trial.

    Science.gov (United States)

    Pecos-Martín, Daniel; Montañez-Aguilera, F Javier; Gallego-Izquierdo, Tomás; Urraca-Gesto, Alicia; Gómez-Conesa, Antonia; Romero-Franco, Natalia; Plaza-Manzano, Gustavo

    2015-05-01

    To evaluate the effect of dry needling into a myofascial trigger point (MTrP) in the lower trapezius muscle of patients with mechanical idiopathic neck pain. A single-center, randomized, double-blinded controlled study. Patients were recruited from the student population of a local hospital by advertisement in the university clinic from January 2010 to December 2011. Patients (N=72) with unilateral neck pain, neck pain for ≥3 months, and active trigger points in the lower trapezius muscle were randomly assigned to 1 of 2 treatment groups. All the patients completed the study. Dry needling in an MTrP in the lower trapezius muscle, or dry needling in the lower trapezius muscle but not at an MTrP. The visual analog scale (VAS), Neck Pain Questionnaire (NPQ), and pressure-pain threshold (PPT) were assessed before the intervention and 1 week and 1 month postintervention. Treatment with dry needling of the lower trapezius muscle close to the MTrP showed decreases in pain and PPT as well as an improvement in the degree of disability (Pdry-needling technique performed in the MTrP showed more significant therapeutic effects (Pdry needling into an active MTrP of the lower trapezius muscle induces significant changes in the VAS, NPQ, and PPT levels compared with the application of dry needling in other locations of the same muscle in patients with mechanical neck pain. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  4. A path-level exact parallelization strategy for sequential simulation

    Science.gov (United States)

    Peredo, Oscar F.; Baeza, Daniel; Ortiz, Julián M.; Herrero, José R.

    2018-01-01

    Sequential Simulation is a well known method in geostatistical modelling. Following the Bayesian approach for simulation of conditionally dependent random events, Sequential Indicator Simulation (SIS) method draws simulated values for K categories (categorical case) or classes defined by K different thresholds (continuous case). Similarly, Sequential Gaussian Simulation (SGS) method draws simulated values from a multivariate Gaussian field. In this work, a path-level approach to parallelize SIS and SGS methods is presented. A first stage of re-arrangement of the simulation path is performed, followed by a second stage of parallel simulation for non-conflicting nodes. A key advantage of the proposed parallelization method is to generate identical realizations as with the original non-parallelized methods. Case studies are presented using two sequential simulation codes from GSLIB: SISIM and SGSIM. Execution time and speedup results are shown for large-scale domains, with many categories and maximum kriging neighbours in each case, achieving high speedup results in the best scenarios using 16 threads of execution in a single machine.

  5. Randomized phase II study of two schedules of flavopiridol given as timed sequential therapy with cytosine arabinoside and mitoxantrone for adults with newly diagnosed, poor-risk acute myelogenous leukemia.

    Science.gov (United States)

    Karp, Judith E; Garrett-Mayer, Elizabeth; Estey, Elihu H; Rudek, Michelle A; Smith, B Douglas; Greer, Jacqueline M; Drye, D Michelle; Mackey, Karen; Dorcy, Kathleen Shannon; Gore, Steven D; Levis, Mark J; McDevitt, Michael A; Carraway, Hetty E; Pratz, Keith W; Gladstone, Douglas E; Showel, Margaret M; Othus, Megan; Doyle, L Austin; Wright, John J; Pagel, John M

    2012-11-01

    Flavopiridol is a protein-bound, cytotoxic, cyclin dependent kinase inhibitor. A phase II trial of flavopiridol followed by ara-C and mitoxantrone with flavopiridol given by 1-h bolus for adults with newly-diagnosed, poor-risk acute myelogenous leukemia yielded 67% complete remission with median disease-free survival of 13.6 months. We compared bolus flavopiridol (50 mg/m(2)/day, Arm A) versus 'hybrid' flavopiridol (30 mg/m(2) over 30 min followed by 40 mg/m(2) over 4 h, Arm B) followed by ara-C and mitoxantrone in 78 patients (39 per arm) with newly diagnosed, poor-risk acute myelogenous leukemia. To mitigate imbalance, patients were stratified by presence or absence of secondary leukemia and therapy for antecedent disorder. Death at or before Day 60 occurred in 8% of patients per arm. Complete remission plus complete remission with incomplete recovery was 68% (Arm A, 62%; Arm B, 74%) overall, and 65% or over in both arms for patients with secondary leukemia and leukemia with adverse genetics. In Arm A 91% and in Arm B 86% of patients received chemotherapy and/or allogeneic transplantation in complete remission. Median overall survival for all remission patients has not been reached for either arm, with median disease free survival of 13.6 months for Arm A and of 12.0 months for Arm B. Both flavopiridol schedules produce comparably encouraging results in adults with poor-risk acute myelogenous leukemia. Given the greater ease of bolus administration, we are conducting a randomized phase II study of bolus flavopiridol followed by ara-c and mitoxantrone versus conventional induction therapy for patients aged 70 years and under with intermediate or poor-risk acute myelogenous leukemia. This study is registered at www.clinicaltrials.gov as #NCT 00407966.

  6. Acute effects of single and multiple level thoracic manipulations on chronic mechanical neck pain: a randomized controlled trial

    Science.gov (United States)

    Puntumetakul, Rungthip; Suvarnnato, Thavatchai; Werasirirat, Phurichaya; Uthaikhup, Sureeporn; Yamauchi, Junichiro; Boucaut, Rose

    2015-01-01

    Background Thoracic spine manipulation has become a popular alternative to local cervical manipulative therapy for mechanical neck pain. This study investigated the acute effects of single-level and multiple-level thoracic manipulations on chronic mechanical neck pain (CMNP). Methods Forty-eight patients with CMNP were randomly allocated to single-level thoracic manipulation (STM) at T6–T7 or multiple-level thoracic manipulation (MTM), or to a control group (prone lying). Cervical range of motion (CROM), visual analog scale (VAS), and the Thai version of the Neck Disability Index (NDI-TH) scores were measured at baseline, and at 24-hour and at 1-week follow-up. Results At 24-hour and 1-week follow-up, neck disability and pain levels were significantly (Pneck disability, pain level at rest, and CROM between the STM and MTM groups. Conclusion These results suggest that both single-level and multiple-level thoracic manipulation improve neck disability, pain levels, and CROM at 24-hour and 1-week follow-up in patients with CMNP. PMID:25624764

  7. The Bacterial Sequential Markov Coalescent.

    Science.gov (United States)

    De Maio, Nicola; Wilson, Daniel J

    2017-05-01

    Bacteria can exchange and acquire new genetic material from other organisms directly and via the environment. This process, known as bacterial recombination, has a strong impact on the evolution of bacteria, for example, leading to the spread of antibiotic resistance across clades and species, and to the avoidance of clonal interference. Recombination hinders phylogenetic and transmission inference because it creates patterns of substitutions (homoplasies) inconsistent with the hypothesis of a single evolutionary tree. Bacterial recombination is typically modeled as statistically akin to gene conversion in eukaryotes, i.e. , using the coalescent with gene conversion (CGC). However, this model can be very computationally demanding as it needs to account for the correlations of evolutionary histories of even distant loci. So, with the increasing popularity of whole genome sequencing, the need has emerged for a faster approach to model and simulate bacterial genome evolution. We present a new model that approximates the coalescent with gene conversion: the bacterial sequential Markov coalescent (BSMC). Our approach is based on a similar idea to the sequential Markov coalescent (SMC)-an approximation of the coalescent with crossover recombination. However, bacterial recombination poses hurdles to a sequential Markov approximation, as it leads to strong correlations and linkage disequilibrium across very distant sites in the genome. Our BSMC overcomes these difficulties, and shows a considerable reduction in computational demand compared to the exact CGC, and very similar patterns in simulated data. We implemented our BSMC model within new simulation software FastSimBac. In addition to the decreased computational demand compared to previous bacterial genome evolution simulators, FastSimBac provides more general options for evolutionary scenarios, allowing population structure with migration, speciation, population size changes, and recombination hotspots. FastSimBac is

  8. On Sequential Communication Schemes with Information Feedback,

    Science.gov (United States)

    INFORMATION THEORY, FEEDBACK), CODING, DATA TRANSMISSION SYSTEMS , WHITE NOISE, DECISION THEORY, STOCHASTIC PROCESSES, SEQUENTIAL ANALYSIS, ERRORS, PROBABILITY DENSITY FUNCTIONS, PARTIAL DIFFERENTIAL EQUATIONS, NUMERICAL INTEGRATION

  9. Sequentially Executed Model Evaluation Framework

    Energy Technology Data Exchange (ETDEWEB)

    2015-10-20

    Provides a message passing framework between generic input, model and output drivers, and specifies an API for developing such drivers. Also provides batch and real-time controllers which step the model and I/O through the time domain (or other discrete domain), and sample I/O drivers. This is a library framework, and does not, itself, solve any problems or execute any modeling. The SeMe framework aids in development of models which operate on sequential information, such as time-series, where evaluation is based on prior results combined with new data for this iteration. Has applications in quality monitoring, and was developed as part of the CANARY-EDS software, where real-time water quality data is being analyzed for anomalies.

  10. Sequential boundaries approach in clinical trials with unequal allocation ratios

    Directory of Open Access Journals (Sweden)

    Ayatollahi Seyyed

    2006-01-01

    Full Text Available Abstract Background In clinical trials, both unequal randomization design and sequential analyses have ethical and economic advantages. In the single-stage-design (SSD, however, if the sample size is not adjusted based on unequal randomization, the power of the trial will decrease, whereas with sequential analysis the power will always remain constant. Our aim was to compare sequential boundaries approach with the SSD when the allocation ratio (R was not equal. Methods We evaluated the influence of R, the ratio of the patients in experimental group to the standard group, on the statistical properties of two-sided tests, including the two-sided single triangular test (TT, double triangular test (DTT and SSD by multiple simulations. The average sample size numbers (ASNs and power (1-β were evaluated for all tests. Results Our simulation study showed that choosing R = 2 instead of R = 1 increases the sample size of SSD by 12% and the ASN of the TT and DTT by the same proportion. Moreover, when R = 2, compared to the adjusted SSD, using the TT or DTT allows to retrieve the well known reductions of ASN observed when R = 1, compared to SSD. In addition, when R = 2, compared to SSD, using the TT and DTT allows to obtain smaller reductions of ASN than when R = 1, but maintains the power of the test to its planned value. Conclusion This study indicates that when the allocation ratio is not equal among the treatment groups, sequential analysis could indeed serve as a compromise between ethicists, economists and statisticians.

  11. Principle and basic property of the sequential flow pump.

    Science.gov (United States)

    Hara, Shintaro; Maeno, Erina; Li, Xinyang; Yurimoto, Terumi; Isoyama, Takashi; Saito, Itsuro; Ono, Toshiya; Abe, Yusuke

    2017-09-01

    In the emergency care field, early treatment of acute heart or respiratory failure has been a global concern. In severe cases, patients are frequently required to be on an extracorporeal membrane oxygenator (ECMO) life support. To make the ECMO system more compact and portable, we proposed a sequential flow-type centrifugal pump named the sequential flow pump (SFP). In this study, principle and basic properties of this novel blood pump were examined by computational fluid dynamic (CFD) analysis and an experimental model. In the SFP, fluid is given centrifugal force sequentially twice with a single closed impeller. This sequential pressurization mechanism enables high-pressure output without high impeller speed. To realize easy integration of a blood pump with an artificial lung, the inlet and outlet ports are located at lateral side and center of the pump, respectively, which is the reverse configuration of conventional centrifugal pumps. The computational model was composed for CFD analysis and the experimental model was developed for the experiment of the actual pump. For both models, dimension of the impeller and volute was designed to be equal. In the CFD analysis, the SFP could generate higher performance than the single pressurization model with the same rotational speed of the impeller. Basic property of the experimental model was very similar to that of the computational model. The results showed the possibility that the SFP would be more suitable for the compact ECMO system than conventional centrifugal pumps.

  12. Randomized clinical trial comparing manual suture and different models of mechanical suture in the mimicking of bariatric surgery in swine

    Directory of Open Access Journals (Sweden)

    Fernandes MA

    2014-02-01

    Full Text Available Marcos AP Fernandes,1 Bruno MT Pereira,2 Sandra M Guimarães,1 Aline Paganelli,3 Carlos Manoel CT Pereira,1 Claudio Sergio Batista4 1Institute of Obesity and Advanced Video Laparoscopic Surgery of Petropolis, Rio de Janeiro, Brazil; 2Division of Trauma, University of Campinas, São Paulo, Brazil; 3Laboratório de Patologia Micron Cell Diagnóstico, Rio de Janeiro, Brazil; 4Department of Gynecology and Obstetrics, Faculty of Medicine of Petropolis, Rio de Janeiro, Brazil Context and objective: Variations in the ability of surgeons served as motivation for the development of devices that, overcoming individual differences, allow the techniques to be properly performed, and of which the end result was the best possible. Every technique must be reproduced reliably by the majority of surgeons for their results to be adopted and recognized as effective. The aim of this study was to compare the results, from the point of view of anatomic pathology, of manual sutures versus mechanical sutures using different models of linear mechanical staplers, in the procedure of gastroenteroanastomosis and enteroanastomosis in swine. Methods: Thirty-six healthy, adult, male Sus scrofa domesticus pigs, weighing between 20.7 and 25.5 kg, were used. The swine were randomly divided into four groups of nine pigs, according to the type of suture employed: group A, manual suture with Polysorb® 3-0 wire; group B, 80-shear linear stapler (Covidien® Gia 8038-S; group C, 75-shear linear stapler (Ethicon® Tlc 75; and group D, 75-shear linear stapler (Resource® Yq 75-3. A temporal study was established on the seventh postoperative day for histopathological analysis, and the degree of inflammation, fibrosis, and newly formed vessels, as well as the presence or absence of granulation tissue, foreign body granuloma, and necrosis were all evaluated qualitatively and semiquantitatively. The results were analyzed statistically. Results: Observations during the histopathological

  13. The efficacy of lumbar extension traction for sagittal alignment in mechanical low back pain: a randomized trial.

    Science.gov (United States)

    Diab, Aliaa Attiah Mohamed; Moustafa, Ibrahim Moustafa

    2013-01-01

    There is growing interest in the role of abnormal asymmetrical posture, which is considered one of the most important etiological factors reported to be associated with mechanical low back pain. This study was conducted to investigate the effect of lumbar extension traction on the pain, function and whole spine sagittal balance as represented in lumbar curvature, thoracic curvature, C7 plumb line, and sacral slope. Eighty patients with chronic mechanical low back pain (CMLBP) and definite hypolordosis were randomly assigned to traction or a control group. The control group (n=40) received stretching exercises and infrared radiation, whereas the traction group (n=40) received lumbar extension traction in addition to stretching exercises and infrared radiation three times a week for 10 weeks. Back pain rating scale, Oswestry Disability Index, and radiological spine sagittal balance parameters in terms of lumbar lordosis, thoracic kyphosis, sacral slope, and positioning of C7 plumb line were measured for all patients at three intervals (before treatment, after 10 weeks of treatment, and at six months follow-up). There was a significant difference between the traction and control groups adjusted to baseline value of outcome at 10 weeks post treatment with respect to lumbar lordotic curve (P=0.000), thoracic kyphosis (P=0.013), sacral slope (P=0.001), C7 plump line distance (p=0.001), while there was no significant difference with respect to pain (p=0.29) and Oswestry Disability Index (ODI) (p=0.1). At 6-months follow-up, there were significant differences between both groups for all the previous variables (pLumbar extension traction in addition to stretching exercises and infrared radiation improved the spine sagittal balance parameters and decreased the pain and disability in CMLBP.

  14. Motor simulation via coupled internal models using sequential Monte Carlo

    OpenAIRE

    Dindo H; Zambuto D.; Pezzulo G.

    2011-01-01

    We describe a generative Bayesian model for action understanding in which inverse-forward internal model pairs are considered 'hypotheses' of plausible action goals that are explored in parallel via an approximate inference mechanism based on sequential Monte Carlo methods. The reenactment of internal model pairs can be considered a form of motor simulation, which supports both perceptual prediction and action understanding at the goal level. However, this procedure is generally considered to...

  15. The role of the local chemical environment of Ag on the resistive switching mechanism of conductive bridging random access memories.

    Science.gov (United States)

    Souchier, E; D'Acapito, F; Noé, P; Blaise, P; Bernard, M; Jousseaume, V

    2015-10-07

    Conductive bridging random access memories (CBRAMs) are one of the most promising emerging technologies for the next generation of non-volatile memory. However, the lack of understanding of the switching mechanism at the nanoscale level prevents successful transfer to industry. In this paper, Ag/GeSx/W CBRAM devices are analyzed using depth selective X-ray Absorption Spectroscopy before and after switching. The study of the local environment around Ag atoms in such devices reveals that Ag is in two very distinct environments with short Ag-S bonds due to Ag dissolved in the GeSx matrix, and longer Ag-Ag bonds related to an Ag metallic phase. These experiments allow the conclusion that the switching process involves the formation of metallic Ag nano-filaments initiated at the Ag electrode. All these experimental features are well supported by ab initio molecular dynamics simulations showing that Ag favorably bonds to S atoms, and permit the proposal of a model at the microscopic level that can explain the instability of the conductive state in these Ag-GeSx CBRAM devices. Finally, the principle of the nondestructive method described here can be extended to other types of resistive memory concepts.

  16. Sequential association rules in atonal music

    NARCIS (Netherlands)

    Honingh, A.; Weyde, T.; Conklin, D.; Chew, E.; Childs, A.; Chuan, C.-H.

    2009-01-01

    This paper describes a preliminary study on the structure of atonal music. In the same way as sequential association rules of chords can be found in tonal music, sequential association rules of pitch class set categories can be found in atonal music. It has been noted before that certain pitch class

  17. Trial Sequential Methods for Meta-Analysis

    Science.gov (United States)

    Kulinskaya, Elena; Wood, John

    2014-01-01

    Statistical methods for sequential meta-analysis have applications also for the design of new trials. Existing methods are based on group sequential methods developed for single trials and start with the calculation of a required information size. This works satisfactorily within the framework of fixed effects meta-analysis, but conceptual…

  18. Multi-agent sequential hypothesis testing

    KAUST Repository

    Kim, Kwang-Ki K.

    2014-12-15

    This paper considers multi-agent sequential hypothesis testing and presents a framework for strategic learning in sequential games with explicit consideration of both temporal and spatial coordination. The associated Bayes risk functions explicitly incorporate costs of taking private/public measurements, costs of time-difference and disagreement in actions of agents, and costs of false declaration/choices in the sequential hypothesis testing. The corresponding sequential decision processes have well-defined value functions with respect to (a) the belief states for the case of conditional independent private noisy measurements that are also assumed to be independent identically distributed over time, and (b) the information states for the case of correlated private noisy measurements. A sequential investment game of strategic coordination and delay is also discussed as an application of the proposed strategic learning rules.

  19. Rationale and study design of ViPS - variable pressure support for weaning from mechanical ventilation: study protocol for an international multicenter randomized controlled open trial.

    Science.gov (United States)

    Kiss, Thomas; Güldner, Andreas; Bluth, Thomas; Uhlig, Christopher; Spieth, Peter Markus; Markstaller, Klaus; Ullrich, Roman; Jaber, Samir; Santos, Jose Alberto; Mancebo, Jordi; Camporota, Luigi; Beale, Richard; Schettino, Guilherme; Saddy, Felipe; Vallverdú, Immaculada; Wiedemann, Bärbel; Koch, Thea; Schultz, Marcus Josephus; Pelosi, Paolo; de Abreu, Marcelo Gama

    2013-10-31

    In pressure support ventilation (PSV), a non-variable level of pressure support is delivered by the ventilator when triggered by the patient. In contrast, variable PSV delivers a level of pressure support that varies in a random fashion, introducing more physiological variability to the respiratory pattern. Experimental studies show that variable PSV improves gas exchange, reduces lung inflammation and the mean pressure support, compared to non-variable PSV. Thus, it can theoretically shorten weaning from the mechanical ventilator. The ViPS (variable pressure support) trial is an international investigator-initiated multicenter randomized controlled open trial comparing variable vs. non-variable PSV. Adult patients on controlled mechanical ventilation for more than 24 hours who are ready to be weaned are eligible for the study. The randomization sequence is blocked per center and performed using a web-based platform. Patients are randomly assigned to one of the two groups: variable PSV or non-variable PSV. In non-variable PSV, breath-by-breath pressure support is kept constant and targeted to achieve a tidal volume of 6 to 8 ml/kg. In variable PSV, the mean pressure support level over a specific time period is targeted at the same mean tidal volume as non-variable PSV, but individual levels vary randomly breath-by-breath. The primary endpoint of the trial is the time to successful weaning, defined as the time from randomization to successful extubation. ViPS is the first randomized controlled trial investigating whether variable, compared to non-variable PSV, shortens the duration of weaning from mechanical ventilation in a mixed population of critically ill patients. This trial aims to determine the role of variable PSV in the intensive care unit. clinicaltrials.gov NCT01769053.

  20. Finger Tendon Travel Associated with Sequential Trigger Nail Gun Use

    Science.gov (United States)

    Lowe, Brian; Albers, James; Hudock, Stephen; Krieg, Edward

    2015-01-01

    TECHNICAL ABSTRACT Background Pneumatic nail guns used in wood framing are equipped with one of two triggering mechanisms. Sequential actuation triggers have been shown to be a safer alternative to contact actuation triggers because they reduce traumatic injury risk. However, the sequential actuation trigger must be depressed for each individual nail fired as opposed to the contact actuation trigger, which allows the trigger to be held depressed as nails are fired repeatedly by bumping the safety tip against the workpiece. As such, concerns have been raised about risks for cumulative trauma injury, and reduced productivity, due to repetitive finger motion with the sequential actuation trigger. Purpose This study developed a method to predict cumulative finger flexor tendon travel associated with the sequential actuation trigger nail gun from finger joint kinematics measured in the trigger actuation and productivity standards for wood-frame construction tasks. Methods Finger motions were measured from six users wearing an instrumented electrogoniometer glove in a simulation of two common framing tasks–wall building and flat nailing of material. Flexor tendon travel was calculated from the ensemble average kinematics for an individual nail fired. Results Finger flexor tendon travel was attributable mostly to proximal interphalangeal and distal interphalangeal joint motion. Tendon travel per nail fired appeared to be slightly greater for a wall-building task than a flat nailing task. The present study data, in combination with construction industry productivity standards, suggest that a high-production workday would be associated with less than 60 m/day cumulative tendon travel per worker (based on 1700 trigger presses/day). Conclusion and Applications These results suggest that exposure to finger tendon travel from sequential actuation trigger nail gun use may be below levels that have been previously associated with high musculoskeletal disorder risk. PMID

  1. Sequential Decay of 26F

    Science.gov (United States)

    Karrick, Hayden; Frank, Nathan; Kuchera, Anthony; Sword, Caleb; Brett, Jaclyn; Deyoung, Paul; Thoennessen, Michael; Mona Collaboration

    2017-09-01

    Unstable neutron rich nuclides show interesting characteristics including multi-neutron emission. By using Jacobi coordinates, multi-neutron emissions from unstable nuclides may be characterized. At the National Superconducting Cyclotron Laboratory experiment, a 101.3 MeV/u 27Ne ion beam hit a liquid deuterium target, causing reactions which produced several nuclides. Many of these nuclides decayed, resulting in a charged fragment and one or more neutrons. A superconducting dipole magnet bent the path of the fragments into a series of charged-particle detectors. Neutrons from these decays were measured as they interacted with arrays of scintillating plastic bars called the MoNA-LISA. The four-momentum vectors of the charged particle and neutron(s) were used to reconstruct the invariant mass. 26F was formed by 1-proton stripping from the 27Ne beam, which resulted in either one or two neutrons emission. A GEANT4 simulation comparison to the experimental data shows that sequential neutron emission resulted from some of the 26F produced. The results of these comparisons will be presented. This material is based upon work supported by the National Science Foundation under Grant PHY-1404236.

  2. Multilevel sequential Monte Carlo samplers

    KAUST Repository

    Beskos, Alexandros

    2016-08-29

    In this article we consider the approximation of expectations w.r.t. probability distributions associated to the solution of partial differential equations (PDEs); this scenario appears routinely in Bayesian inverse problems. In practice, one often has to solve the associated PDE numerically, using, for instance finite element methods which depend on the step-size level . hL. In addition, the expectation cannot be computed analytically and one often resorts to Monte Carlo methods. In the context of this problem, it is known that the introduction of the multilevel Monte Carlo (MLMC) method can reduce the amount of computational effort to estimate expectations, for a given level of error. This is achieved via a telescoping identity associated to a Monte Carlo approximation of a sequence of probability distributions with discretization levels . ∞>h0>h1⋯>hL. In many practical problems of interest, one cannot achieve an i.i.d. sampling of the associated sequence and a sequential Monte Carlo (SMC) version of the MLMC method is introduced to deal with this problem. It is shown that under appropriate assumptions, the attractive property of a reduction of the amount of computational effort to estimate expectations, for a given level of error, can be maintained within the SMC context. That is, relative to exact sampling and Monte Carlo for the distribution at the finest level . hL. The approach is numerically illustrated on a Bayesian inverse problem. © 2016 Elsevier B.V.

  3. The working mechanisms of an environmentally tailored physical activity intervention for older adults: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Mudde Aart N

    2009-12-01

    Full Text Available Abstract Background The aim of this study was to explore the working mechanisms of a computer tailored physical activity intervention for older adults with environmental information compared to a basic tailored intervention without environmental information. Method A clustered randomized controlled trial with two computer tailored interventions and a no-intervention control group was conducted among 1971 adults aged ≥ 50. The two tailored interventions were developed using Intervention Mapping and consisted of three tailored letters delivered over a four-month period. The basic tailored intervention targeted psychosocial determinants alone, while the environmentally tailored intervention additionally targeted environmental determinants, by providing tailored environmental information. Study outcomes were collected with questionnaires at baseline, three and six months and comprised total physical activity (days/week, walking (min/week, cycling (min/week, sports (min/week, environmental perceptions and use and appreciation of the interventions. Results Mediation analyses showed that changes in cycling, sports and total physical activity behaviour induced by the environmentally tailored intervention were mediated by changes in environmental perceptions. Changes in environmental perceptions did not mediate the effect of the basic tailored intervention on behaviour. Compared with the basic tailored intervention, the environmentally tailored intervention significantly improved cycling behaviour (τ = 30.2. Additionally, the tailored letters of the environmentally tailored intervention were better appreciated and used, although these differences did not mediate the intervention effect. Discussion This study gave some first indications of the relevance of environmental perceptions as a determinant of changing physical activity behaviours and the potential effectiveness of providing environmental information as an intervention strategy aimed at

  4. Post-Exercise Hypotension and Its Mechanisms Differ after Morning and Evening Exercise: A Randomized Crossover Study.

    Science.gov (United States)

    de Brito, Leandro C; Rezende, Rafael A; da Silva Junior, Natan D; Tinucci, Tais; Casarini, Dulce E; Cipolla-Neto, José; Forjaz, Cláudia L M

    2015-01-01

    Post-exercise hypotension (PEH), calculated by the difference between post and pre-exercise values, it is greater after exercise performed in the evening than the morning. However, the hypotensive effect of morning exercise may be masked by the morning circadian increase in blood pressure. This study investigated PEH and its hemodynamic and autonomic mechanisms after sessions of aerobic exercise performed in the morning and evening, controlling for responses observed after control sessions performed at the same times of day. Sixteen pre-hypertensive men underwent four sessions (random order): two conducted in the morning (7:30 am) and two in the evening (5 pm). At each time of day, subjects underwent an exercise (cycling, 45 min, 50%VO2peak) and a control (sitting rest) session. Measurements were taken pre- and post-interventions in all the sessions. The net effects of exercise were calculated for each time of day by [(post-pre exercise)-(post-pre control)] and were compared by paired t-test (PExercise hypotensive net effects (e.g., decreasing systolic, diastolic and mean blood pressure) occurred at both times of day, but systolic blood pressure reductions were greater after morning exercise (-7±3 vs. -3±4 mmHg, PExercise decreased cardiac output only in the morning (-460±771 ml/min, Ptimes of day and increased heart rate less in the morning than in the evening (+7±5 vs. +10±5 bpm, Pevening exercise increased sympathovagal balance (+1.5±1.6, Pexercise conducted at both times of day, but the systolic hypotensive effect is greater after morning exercise when circadian variations are considered. This greater effect is accompanied by a reduction of cardiac output due to a smaller increase in heart rate and cardiac sympathovagal balance.

  5. [Randomized controlled trials on the influence and mechanism of manipulation on delayed onset muscle soreness after eccentric exercise].

    Science.gov (United States)

    Xiong, Ying; Wu, Yun-Chuan; Jin, Hong-Zhu; Gu, Yi-Huang

    2009-09-01

    To observe and compare the influence of pre- and post-exercise manipulation and natural recovery without any intervention on delayed onset muscle soreness (DOMS) after eccentric exercise and to explore the manipulation therapeutic mechanism on the metabolism of oxygen free radical (OFR). The study was carried on during Apr. to Jul. in 2008 at Nanjing University of TCM. The 30 healthy male students were divided into 3 groups randomly according to condition-equivalence principle including control group (C), pre-exercise manipulation group (A), post-exercise manipulation group (B). Before exercise, group A were intervened by manipulation for 30 minutes, which was followed by exercise 5 minutes later. While 30 minutes after exercise, group B accepted manipulation for 30 minutes and continued manipulation once a day for consecutive 3 days. Group C were not intervened by any approaches before or after exercise. The clinical manifestations, which include soreness intensity and lasting time, maximal isometric strength, arm girth, elbow range of motion, were evaluated at the 1st hour before exercise, immediately, 24th, 48th and 72th hours after exercise. Meanwhile, serum creatine kinase (CK), serum superoxide dismutase (SOD), serum malonaldehyde (MDA) were determined at the 1st hour before exercise, immediately, 24th and 48th hours after exercise. Compared to group C, group A and B were manifested by significantly lower peak soreness (P manipulation can partially prevent and treat DOMS respectively. In addition, preventive effect by pre-exercise manipulation is better than curing effect by post-exercise manipulation, which proves the TCM thought, that is, prevention superior to treatment.

  6. Acute effects of single and multiple level thoracic manipulations on chronic mechanical neck pain: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Puntumetakul R

    2015-01-01

    Full Text Available Rungthip Puntumetakul,1,2 Thavatchai Suvarnnato,1,3 Phurichaya Werasirirat,1 Sureeporn Uthaikhup,2 Junichiro Yamauchi,4,5 Rose Boucaut6 1School of Physical Therapy, Faculty of Associated Medical Sciences, 2Research Center in Back, Neck, Other Joint Pain and Human Performance, 3Physical Therapy Unit, Srinagarind Hospital, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand; 4Graduate School of Human Health Sciences, Tokyo Metropolitan University, 5Future Institute for Sport Sciences, Tokyo, Japan; 6School of Health Sciences (Physiotherapy, University of South Australia, Adelaide, SA, Australia Background: Thoracic spine manipulation has become a popular alternative to local cervical manipulative therapy for mechanical neck pain. This study investigated the acute effects of single-level and multiple-level thoracic manipulations on chronic mechanical neck pain (CMNP.Methods: Forty-eight patients with CMNP were randomly allocated to single-level thoracic manipulation (STM at T6–T7 or multiple-level thoracic manipulation (MTM, or to a control group (prone lying. Cervical range of motion (CROM, visual analog scale (VAS, and the Thai version of the Neck Disability Index (NDI-TH scores were measured at baseline, and at 24-hour and at 1-week follow-up.Results: At 24-hour and 1-week follow-up, neck disability and pain levels were significantly (P<0.05 improved in the STM and MTM groups compared with the control group. CROM in flexion and left lateral flexion were increased significantly (P<0.05 in the STM group when compared with the control group at 1-week follow-up. The CROM in right rotation was increased significantly after MTM compared to the control group (P<0.05 at 24-hour follow-up. There were no statistically significant differences in neck disability, pain level at rest, and CROM between the STM and MTM groups.Conclusion: These results suggest that both single-level and multiple-level thoracic manipulation improve neck disability

  7. Sequential experimental design based generalised ANOVA

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, Souvik, E-mail: csouvik41@gmail.com; Chowdhury, Rajib, E-mail: rajibfce@iitr.ac.in

    2016-07-15

    Over the last decade, surrogate modelling technique has gained wide popularity in the field of uncertainty quantification, optimization, model exploration and sensitivity analysis. This approach relies on experimental design to generate training points and regression/interpolation for generating the surrogate. In this work, it is argued that conventional experimental design may render a surrogate model inefficient. In order to address this issue, this paper presents a novel distribution adaptive sequential experimental design (DA-SED). The proposed DA-SED has been coupled with a variant of generalised analysis of variance (G-ANOVA), developed by representing the component function using the generalised polynomial chaos expansion. Moreover, generalised analytical expressions for calculating the first two statistical moments of the response, which are utilized in predicting the probability of failure, have also been developed. The proposed approach has been utilized in predicting probability of failure of three structural mechanics problems. It is observed that the proposed approach yields accurate and computationally efficient estimate of the failure probability.

  8. Safeguarding a Lunar Rover with Wald's Sequential Probability Ratio Test

    Science.gov (United States)

    Furlong, Michael; Dille, Michael; Wong, Uland; Nefian, Ara

    2016-01-01

    The virtual bumper is a safeguarding mechanism for autonomous and remotely operated robots. In this paper we take a new approach to the virtual bumper system by using an old statistical test. By using a modified version of Wald's sequential probability ratio test we demonstrate that we can reduce the number of false positive reported by the virtual bumper, thereby saving valuable mission time. We use the concept of sequential probability ratio to control vehicle speed in the presence of possible obstacles in order to increase certainty about whether or not obstacles are present. Our new algorithm reduces the chances of collision by approximately 98 relative to traditional virtual bumper safeguarding without speed control.

  9. Random number generators and the Metropolis algorithm: application to various problems in physics and mechanics as an introduction to computational physics

    Energy Technology Data Exchange (ETDEWEB)

    Calvayrac, Florent [Laboratoire de Physique de l' Etat Condense, UMR CNRS 6087 and FR 2575, Universite du Maine, 72085 Le Mans Cedex 9 (France)

    2005-09-01

    We present known and new applications of pseudo random numbers and of the Metropolis algorithm to phenomena of physical and mechanical interest, such as the search of simple clusters isomers with interactive visualization, or vehicle motion planning. The progression towards complicated problems was used with first-year graduate students who wrote most of the programs presented here. We argue that the use of pseudo random numbers in simulation and extrema research programs in teaching numerical methods in physics allows one to get quick programs and physically meaningful and demonstrative results without recurring to the advanced numerical analysis methods.

  10. Optimal sequential measurements for bipartite state discrimination

    Science.gov (United States)

    Croke, Sarah; Barnett, Stephen M.; Weir, Graeme

    2017-05-01

    State discrimination is a useful test problem with which to clarify the power and limitations of different classes of measurement. We consider the problem of discriminating between given states of a bipartite quantum system via sequential measurement of the subsystems, with classical feed-forward of measurement results. Our aim is to understand when sequential measurements, which are relatively easy to implement experimentally, perform as well, or almost as well, as optimal joint measurements, which are in general more technologically challenging. We construct conditions that the optimal sequential measurement must satisfy, analogous to the well-known Helstrom conditions for minimum error discrimination in the unrestricted case. We give several examples and compare the optimal probability of correctly identifying the state via global versus sequential measurement strategies.

  11. Efficacy of premixed versus sequential administration of ...

    African Journals Online (AJOL)

    Objective: To evaluate the efficacy of intrathecal hyperbaric bupivacaine premixed with dexmeditomidine compared with sequential administration in separate syringes on block characteristics, haemodynamic parameters, side effect profile and postoperative analgesic requirement. Trial design: This was a prospective, ...

  12. Sequential testing problems for Poisson processes

    OpenAIRE

    Peskir, G; A.N. Shiryaev

    2000-01-01

    We present the explicit solution of the Bayesian problem of sequential testing of two simple hypotheses about the intensity of an observed Poisson process. The method of proof consists of reducing the initial problem to a free-boundary differential-difference Stephan problem and solving the latter by use of the principles of smooth and continuous fit. A rigorous proof of the optimality of the Wald’s sequential probability ratio test in the variational formulation of the prob...

  13. Simultaneous vs sequential adjustments in a duopoly

    Science.gov (United States)

    Ibrahim, Adyda; Karim, Sharmila; Zaibidi, Nerda Zura

    2014-12-01

    In a duopoly situation, two firms can move towards the equilibrium point either sequentially or simultaneously. In the case of equal costs and equal initial outputs, numerical results in this paper show the effect of simultaneous adjustment and sequential adjustment on the length of time it takes for a firm to reach the Cournot equilibrium, and the total profit accumulated up until reaching the equilibrium point.

  14. Post-Exercise Hypotension and Its Mechanisms Differ after Morning and Evening Exercise: A Randomized Crossover Study.

    Directory of Open Access Journals (Sweden)

    Leandro C de Brito

    Full Text Available Post-exercise hypotension (PEH, calculated by the difference between post and pre-exercise values, it is greater after exercise performed in the evening than the morning. However, the hypotensive effect of morning exercise may be masked by the morning circadian increase in blood pressure. This study investigated PEH and its hemodynamic and autonomic mechanisms after sessions of aerobic exercise performed in the morning and evening, controlling for responses observed after control sessions performed at the same times of day. Sixteen pre-hypertensive men underwent four sessions (random order: two conducted in the morning (7:30 am and two in the evening (5 pm. At each time of day, subjects underwent an exercise (cycling, 45 min, 50%VO2peak and a control (sitting rest session. Measurements were taken pre- and post-interventions in all the sessions. The net effects of exercise were calculated for each time of day by [(post-pre exercise-(post-pre control] and were compared by paired t-test (P<0.05. Exercise hypotensive net effects (e.g., decreasing systolic, diastolic and mean blood pressure occurred at both times of day, but systolic blood pressure reductions were greater after morning exercise (-7±3 vs. -3±4 mmHg, P<0.05. Exercise decreased cardiac output only in the morning (-460±771 ml/min, P<0.05, while it decreased stroke volume similarly at both times of day and increased heart rate less in the morning than in the evening (+7±5 vs. +10±5 bpm, P<0.05. Only evening exercise increased sympathovagal balance (+1.5±1.6, P<0.05 and calf blood flow responses to reactive hyperemia (+120±179 vs. -70±188 U, P<0.05. In conclusion, PEH occurs after exercise conducted at both times of day, but the systolic hypotensive effect is greater after morning exercise when circadian variations are considered. This greater effect is accompanied by a reduction of cardiac output due to a smaller increase in heart rate and cardiac sympathovagal balance.

  15. Outcome of late-life depression after 3 years of sequential treatment

    NARCIS (Netherlands)

    Kok, R. M.; Nolen, W. A.; Heeren, T. J.

    To study the outcome of a sequential treatment protocol in elderly, severely depressed in-patients. All 81 patients from a 12-week double-blind randomized controlled trial (RCT) comparing venlafaxine with nortriptyline were asked to participate in a 3 year follow-up study. Thirty-two patients who

  16. The Minimum Requirements of Language Control: Evidence from Sequential Predictability Effects in Language Switching

    Science.gov (United States)

    Declerck, Mathieu; Koch, Iring; Philipp, Andrea M.

    2015-01-01

    The current study systematically examined the influence of sequential predictability of languages and concepts on language switching. To this end, 2 language switching paradigms were combined. To measure language switching with a random sequence of languages and/or concepts, we used a language switching paradigm that implements visual cues and…

  17. Mechanics

    CERN Document Server

    Hartog, J P Den

    1961-01-01

    First published over 40 years ago, this work has achieved the status of a classic among introductory texts on mechanics. Den Hartog is known for his lively, discursive and often witty presentations of all the fundamental material of both statics and dynamics (and considerable more advanced material) in new, original ways that provide students with insights into mechanical relationships that other books do not always succeed in conveying. On the other hand, the work is so replete with engineering applications and actual design problems that it is as valuable as a reference to the practicing e

  18. Multi-channel Dual Clocks three-dimensional probability Random Multiple Access protocol for Wireless Public Bus Networks based on RTS/CTS mechanism

    Directory of Open Access Journals (Sweden)

    Zhou Sheng Jie

    2016-01-01

    Full Text Available A MAC protocol for public bus networks, called Bus MAC protocol, designed to provide high quality Internet service for bus passengers. The paper proposed a multi-channel dual clocks three-demission probability random multiple access protocol based on RTS/CTS mechanism, decreasing collisions caused by multiple access from multiple passengers. Use the RTS/CTS mechanism increases the reliability and stability of the system, reducing the collision possibility of the information packets to a certain extent, improves the channel utilization; use the multi-channel mechanism, not only enables the channel load balancing, but also solves the problem of the hidden terminal and exposed terminal. Use the dual clocks mechanism, reducing the system idle time. At last, the different selection of the three-dimensional probabilities can make the system throughput adapt to the network load which could realize the maximum of the system throughput.

  19. Incorporation of mesoporous silica nanoparticles into random electrospun PLGA and PLGA/gelatin nanofibrous scaffolds enhances mechanical and cell proliferation properties

    DEFF Research Database (Denmark)

    Mehrasa, Mohammad; Asadollahi, Mohammad Ali; Nasri-Nasrabadi, Bijan

    2016-01-01

    Poly(lactic-co-glycolic.acid) (PLGA) and PLGA/gelatin random nanofibrous scaffolds embedded with different amounts of mesoporous silica nanoparticles (MSNPs) were fabricated using electrospinning method. To evaluate the effects of nanoparticles on the scaffolds, physical, chemical, and mechanical...... the porosity of scaffolds. Nanoparticles also improved the tensile mechanical properties of scaffolds. Using in vitro degradation analysis, it was shown that the addition of nanoparticles to the nano fibers matrix increases the weight loss percentage of PLGA-based samples, whereas it decreases the weight loss...

  20. Sequential microcontroller-based control for a chemical vapor deposition process

    Directory of Open Access Journals (Sweden)

    Edgar Serrano Pérez

    2017-12-01

    Full Text Available A cost-effective direct liquid injection system is developed for a chemical vapor deposition process using a microcontroller. The precursor gas phase is controlled by the precise sequential injection of a liquid precursor solution to a vaporizing chamber prior deposition. The electronic control system allows the human–machine interface through a LCD display and a keypad matrix. The core of the electronic system is based on an electro mechanical injector operated in time and frequency as a sequential control system by a popular PIC16F877A chip. The software has been developed in the BASIC language and it can be easily modified through an ICSP programmer for different sequential automatized routines. The injection calibration test has proven the linearity of the injection control system for different operation parameters. The results reported the sequential injection MOCVD deposition of alumina thin film.

  1. Hierarchical Chunking of Sequential Memory on Neuromorphic Architecture with Reduced Synaptic Plasticity.

    Science.gov (United States)

    Li, Guoqi; Deng, Lei; Wang, Dong; Wang, Wei; Zeng, Fei; Zhang, Ziyang; Li, Huanglong; Song, Sen; Pei, Jing; Shi, Luping

    2016-01-01

    Chunking refers to a phenomenon whereby individuals group items together when performing a memory task to improve the performance of sequential memory. In this work, we build a bio-plausible hierarchical chunking of sequential memory (HCSM) model to explain why such improvement happens. We address this issue by linking hierarchical chunking with synaptic plasticity and neuromorphic engineering. We uncover that a chunking mechanism reduces the requirements of synaptic plasticity since it allows applying synapses with narrow dynamic range and low precision to perform a memory task. We validate a hardware version of the model through simulation, based on measured memristor behavior with narrow dynamic range in neuromorphic circuits, which reveals how chunking works and what role it plays in encoding sequential memory. Our work deepens the understanding of sequential memory and enables incorporating it for the investigation of the brain-inspired computing on neuromorphic architecture.

  2. Sequential transitions of bathtub vortex flow

    Science.gov (United States)

    Mizushima, Jiro; Abe, Kazuki; Yokoyama, Naoto

    2017-08-01

    The bathtub vortex has been found to autonomously arise owing to instability of a symmetric flow in a rectangular vessel when water is drained. We consider a model flow through a vessel with a rectangular horizontal cross section and a drain hole at the center of the bottom to investigate the physical mechanism for generation of swirling fluid motion like the bathtub vortex and the sequential transitions of the flow by numerical simulations and the linear stability analyses. The water surface is assumed to be flat even after instability. If the flow becomes unstable under this assumption, it assures that the surface deformation is irrelevant to the instability. It is emphasized that our interest is not limited to the real bathtub vortex but directed to occurrence of a large vortex in a flow having two reflectional symmetries. The configuration of the vessel has the double plane symmetry (DPS), which allows the flow have the same DPS at small Reynolds numbers. It is found that the instabilities and hence transitions occur accompanying symmetry-breaking of the flow field. Namely, the DPS flow experiences instability to yield vortical motion above a critical Reynolds number, losing the DPS but retaining the π -rotational (twofold rotational) symmetry around the center axis. The vortical flow also becomes unstable at a higher Reynolds number, makes a transition, and loses the π -rotational symmetry, but still keeps the time-translation symmetry, i.e., steadiness. The steadiness is broken at an even higher Reynolds number, owing to instability caused by an oscillatory mode of disturbance. The first and second transitions of the flow are identified as pitchfork bifurcations, and the third transition is identified as a Hopf bifurcation.

  3. Effect of Acetazolamide vs Placebo on Duration of Invasive Mechanical Ventilation Among Patients With Chronic Obstructive Pulmonary Disease: A Randomized Clinical Trial.

    Science.gov (United States)

    Faisy, Christophe; Meziani, Ferhat; Planquette, Benjamin; Clavel, Marc; Gacouin, Arnaud; Bornstain, Caroline; Schneider, Francis; Duguet, Alexandre; Gibot, Sébastien; Lerolle, Nicolas; Ricard, Jean-Damien; Sanchez, Olivier; Djibre, Michel; Ricome, Jean-Louis; Rabbat, Antoine; Heming, Nicholas; Urien, Saïk; Esvan, Maxime; Katsahian, Sandrine

    2016-02-02

    Acetazolamide has been used for decades as a respiratory stimulant for patients with chronic obstructive pulmonary disease (COPD) and metabolic alkalosis, but no large randomized placebo-controlled trial is available to confirm this approach. To determine whether acetazolamide reduces mechanical ventilation duration in critically ill patients with COPD and metabolic alkalosis. The DIABOLO study, a randomized, double-blind, multicenter trial, was conducted from October 2011 through July 2014 in 15 intensive care units (ICUs) in France. A total of 382 patients with COPD who were expected to receive mechanical ventilation for more 24 hours were randomized to the acetazolamide or placebo group and 380 were included in an intention-to treat analysis. Acetazolamide (500-1000 mg, twice daily) vs placebo administered intravenously in cases of pure or mixed metabolic alkalosis, initiated within 48 hours of ICU admission and continued during the ICU stay for a maximum of 28 days. The primary outcome was the duration of invasive mechanical ventilation via endotracheal intubation or tracheotomy. Secondary outcomes included changes in arterial blood gas and respiratory parameters, weaning duration, adverse events, use of noninvasive ventilation after extubation, successful weaning, the duration of ICU stay, and in-ICU mortality. Among 382 randomized patients, 380 (mean age, 69 years; 272 men [71.6%]; 379 [99.7%] with endotracheal intubation) completed the study. For the acetazolamide group (n = 187), compared with the placebo group (n = 193), no significant between-group differences were found for median duration of mechanical ventilation (-16.0 hours; 95% CI, -36.5 to 4.0 hours; P = .17), duration of weaning off mechanical ventilation (-0.9 hours; 95% CI, -4.3 to 1.3 hours; P = .36), daily changes of minute-ventilation (-0.0 L/min; 95% CI, -0.2 to 0.2 L/min; P = .72), or partial carbon-dioxide pressure in arterial blood (-0.3 mm Hg; 95% CI, -0.8 to 0.2 mm

  4. Goal-independent mechanisms for free response generation: creative and pseudo-random performance share neural substrates.

    Science.gov (United States)

    de Manzano, Örjan; Ullén, Fredrik

    2012-01-02

    To what extent free response generation in different tasks uses common and task-specific neurocognitive processes has remained unclear. Here, we investigated overlap and differences in neural activity during musical improvisation and pseudo-random response generation. Brain activity was measured using fMRI in a group of professional classical pianists, who performed musical improvisation of melodies, pseudo-random key-presses and a baseline condition (sight-reading), on either two, six or twelve keys on a piano keyboard. The results revealed an extensive overlap in neural activity between the two generative conditions. Active regions included the dorsolateral and dorsomedial prefrontal cortices, inferior frontal gyrus, anterior cingulate cortex and pre-SMA. No regions showed higher activity in improvisation than in pseudo-random generation. These findings suggest that the activated regions fulfill generic functions that are utilized in different types of free generation tasks, independent of overall goal. In contrast, pseudo-random generation was accompanied by higher activity than improvisation in several regions. This presumably reflects the participants' musical expertise as well as the pseudo-random generation task's high load on attention, working memory, and executive control. The results highlight the significance of using naturalistic tasks to study human behavior and cognition. No brain activity was related to the size of the response set. We discuss that this may reflect that the musicians were able to use specific strategies for improvisation, by which there was no simple relationship between response set size and neural activity. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Batch sequential designs for computer experiments

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Leslie M [Los Alamos National Laboratory; Williams, Brian J [Los Alamos National Laboratory; Loeppky, Jason L [UBC-OKANAGAN

    2009-01-01

    Computer models simulating a physical process are used in many areas of science. Due to the complex nature of these codes it is often necessary to approximate the code, which is typically done using a Gaussian process. In many situations the number of code runs available to build the Guassian process approximation is limited. When the initial design is small or the underlying response surface is complicated this can lead to poor approximations of the code output. In order to improve the fit of the model, sequential design strategies must be employed. In this paper we introduce two simple distance based metrics that can be used to augment an initial design in a batch sequential manner. In addition we propose a sequential updating strategy to an orthogonal array based Latin hypercube sample. We show via various real and simulated examples that the distance metrics and the extension of the orthogonal array based Latin hypercubes work well in practice.

  6. Sequential Path Entanglement for Quantum Metrology

    Science.gov (United States)

    Jin, Xian-Min; Peng, Cheng-Zhi; Deng, Youjin; Barbieri, Marco; Nunn, Joshua; Walmsley, Ian A.

    2013-01-01

    Path entanglement is a key resource for quantum metrology. Using path-entangled states, the standard quantum limit can be beaten, and the Heisenberg limit can be achieved. However, the preparation and detection of such states scales unfavourably with the number of photons. Here we introduce sequential path entanglement, in which photons are distributed across distinct time bins with arbitrary separation, as a resource for quantum metrology. We demonstrate a scheme for converting polarization Greenberger-Horne-Zeilinger entanglement into sequential path entanglement. We observe the same enhanced phase resolution expected for conventional path entanglement, independent of the delay between consecutive photons. Sequential path entanglement can be prepared comparably easily from polarization entanglement, can be detected without using photon-number-resolving detectors, and enables novel applications.

  7. Effects of procalcitonin-guided treatment on antibiotic use and need for mechanical ventilation in patients with acute asthma exacerbation: Meta-analysis of randomized controlled trials

    Directory of Open Access Journals (Sweden)

    Wanis H. Ibrahim

    2017-12-01

    Full Text Available Objective: The primary outcome was to determine whether serum procalcitonin-guided antibiotic therapy can reduce antibiotic exposure in patients with an acute exacerbation of asthma presenting to the primary care facility or emergency department, or during hospital admission. The secondary outcome was the need for mechanical ventilation. Methods: An extensive literature search was performed to identify randomized controlled clinical trials (published in English that compared serum procalcitonin-guided antibiotic therapy versus antibiotic use according to physician’s discretion for adult participants with mild, moderate, or severe acute asthma exacerbations. Results: Four randomized controlled trials evaluating 457 patients were included in this meta-analysis, with significant homogeneity observed among these studies. Procalcitonin-based protocols decreased antibiotic prescriptions (relative risk 0.58, 95% confidence interval 0.50–0.67. The conclusion regarding the difference between the two groups in the need for mechanical ventilation (relative risk 1.10, 95% confidence interval 0.62–1.94 was guarded due to inadequate power and the potential for type II error. The overall quality of evidence was also limited by the lack of double-blinding. Conclusions: These data suggest a potential benefit for the use of serum procalcitonin in guiding antibiotic therapy in patients with an acute asthma exacerbation and advocates the need for more randomized controlled trials. Keywords: Procalcitonin, Asthma, Antibiotic, Exacerbation, Guided

  8. Effects of procalcitonin-guided treatment on antibiotic use and need for mechanical ventilation in patients with acute asthma exacerbation: Meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Ibrahim, Wanis H; Mushtaq, Kamran; Raza, Tasleem; Kartha, Anand; Saleh, Ahmed O; Malik, Rayaz A

    2017-12-01

    The primary outcome was to determine whether serum procalcitonin-guided antibiotic therapy can reduce antibiotic exposure in patients with an acute exacerbation of asthma presenting to the primary care facility or emergency department, or during hospital admission. The secondary outcome was the need for mechanical ventilation. An extensive literature search was performed to identify randomized controlled clinical trials (published in English) that compared serum procalcitonin-guided antibiotic therapy versus antibiotic use according to physician's discretion for adult participants with mild, moderate, or severe acute asthma exacerbations. Four randomized controlled trials evaluating 457 patients were included in this meta-analysis, with significant homogeneity observed among these studies. Procalcitonin-based protocols decreased antibiotic prescriptions (relative risk 0.58, 95% confidence interval 0.50-0.67). The conclusion regarding the difference between the two groups in the need for mechanical ventilation (relative risk 1.10, 95% confidence interval 0.62-1.94) was guarded due to inadequate power and the potential for type II error. The overall quality of evidence was also limited by the lack of double-blinding. These data suggest a potential benefit for the use of serum procalcitonin in guiding antibiotic therapy in patients with an acute asthma exacerbation and advocates the need for more randomized controlled trials. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  9. Passive Baited Sequential Filth Fly Trap.

    Science.gov (United States)

    Aldridge, Robert L; Britch, Seth C; Snelling, Melissa; Gutierez, Arturo; White, Gregory; Linthicum, Kenneth J

    2015-09-01

    Filth fly control measures may be optimized with a better understanding of fly population dynamics measured throughout the day. We describe the modification of a commercial motorized sequential mosquito trap to accept liquid odorous bait and leverage a classic inverted-cone design to passively confine flies in 8 modified collection bottles corresponding to 8 intervals. Efficacy trials in a hot-arid desert environment indicate no significant difference (P  =  0.896) between the modified sequential trap and a Rid-Max® fly trap.

  10. Double sequential defibrillation for refractory ventricular fibrillation.

    Science.gov (United States)

    El Tawil, Chady; Mrad, Sandra; Khishfe, Basem F

    2017-12-01

    A 54-year-old suffered from an out-of-hospital cardiac arrest. Compressions were started within minutes and the patient was in refractory ventricular fibrillation despite multiple asynchronized shocks and maximal doses of antiarrhythmic agents. Double sequential defibrillation was attempted with successful Return Of Spontaneous Circulation (ROSC) after a total of 61min of cardiac arrest. The patient was discharged home neurologically intact. Double sequential defibrillation could be a simple effective approach to patients with refractory ventricular fibrillation. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Comparison of efficacy and safety of levofloxacin-containing versus standard sequential therapy in eradication of Helicobacter pylori infection in Korea.

    Science.gov (United States)

    Lee, Hyuk; Hong, Sung Noh; Min, Byung-Hoon; Lee, Jun Haeng; Rhee, Poong-Lyul; Lee, Yong Chan; Kim, Jae J

    2015-02-01

    Declining of eradication rates for Helicobacter pylori in Korea may be partly from the increasing prevalence of antibiotic resistance, especially clarithromycin resistance. To compare the efficacy and the safety of using 10-day standard sequential therapy and levofloxacin-containing sequential therapy as a first-line treatment for Helicobacter pylori eradication in Korea. A total of 200 patients with proven Helicobacter pylori infection randomly received 10-day standard sequential therapy (n = 100) or levofloxacin-containing sequential therapy (n = 100). The standard sequential therapy group received rabeprazole and amoxicillin for 5 days, followed by rabeprazole, clarithromycin, and metronidazole for 5 more days. The levofloxacin-containing sequential therapy group was treated with rabeprazole and amoxicillin for 5 days, followed by rabeprazole, levofloxacin, and metronidazole for 5 more days. Intention-to-treat eradication rates were 79.0% and 78.0% for groups of standard sequential and levofloxacin-containing sequential therapy, respectively (P = 0.863). Per-protocol eradication rates were 84.9% and 81.3%, respectively, for these two therapies (P = 0.498). There were no significant differences between the groups in regard to the eradication rates and adverse events. The 10-day levofloxacin-containing sequential regimen and the standard sequential regimen showed the similar eradication rates of Helicobacter pylori in Korea. Copyright © 2014 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  12. Mechanics

    CERN Document Server

    Chester, W

    1979-01-01

    When I began to write this book, I originally had in mind the needs of university students in their first year. May aim was to keep the mathematics simple. No advanced techniques are used and there are no complicated applications. The emphasis is on an understanding of the basic ideas and problems which require expertise but do not contribute to this understanding are not discussed. How­ ever, the presentation is more sophisticated than might be considered appropri­ ate for someone with no previous knowledge of the subject so that, although it is developed from the beginning, some previous acquaintance with the elements of the subject would be an advantage. In addition, some familiarity with element­ ary calculus is assumed but not with the elementary theory of differential equations, although knowledge of the latter would again be an advantage. It is my opinion that mechanics is best introduced through the motion of a particle, with rigid body problems left until the subject is more fully developed. Howev...

  13. Nebulized heparin is associated with fewer days of mechanical ventilation in critically ill patients: a randomized controlled trial

    NARCIS (Netherlands)

    Dixon, Barry; Schultz, Marcus J.; Smith, Roger; Fink, James B.; Santamaria, John D.; Campbell, Duncan J.

    2010-01-01

    Prolonged mechanical ventilation has the potential to aggravate or initiate pulmonary inflammation and cause lung damage through fibrin deposition. Heparin may reduce pulmonary inflammation and fibrin deposition. We therefore assessed whether nebulized heparin improved lung function in patients

  14. Variable versus conventional lung protective mechanical ventilation during open abdominal surgery: study protocol for a randomized controlled trial

    NARCIS (Netherlands)

    Spieth, Peter M.; Güldner, Andreas; Uhlig, Christopher; Bluth, Thomas; Kiss, Thomas; Schultz, Marcus J.; Pelosi, Paolo; Koch, Thea; Gama de Abreu, Marcelo

    2014-01-01

    General anesthesia usually requires mechanical ventilation, which is traditionally accomplished with constant tidal volumes in volume- or pressure-controlled modes. Experimental studies suggest that the use of variable tidal volumes (variable ventilation) recruits lung tissue, improves pulmonary

  15. Music and biological stress dampening in mechanically-ventilated patients at the intensive care unit ward-a prospective interventional randomized crossover trial.

    Science.gov (United States)

    Beaulieu-Boire, Genevieve; Bourque, Solange; Chagnon, Frederic; Chouinard, Lucie; Gallo-Payet, Nicole; Lesur, Olivier

    2013-08-01

    To evaluate the impact of slow-tempo music listening periods in mechanically ventilated intensive care unit patients. A randomized crossover study was performed in a 16-bed, adult critical care unit at a tertiary care hospital. Still-sedated patients, mandating at least 3 more days of mechanical ventilation, were included. The intervention consisted in two 1-hour daily periods of music-vs-sham-MP3 listening which were performed on Day 1 or 3 post-inclusion, with a Day 2 wash-out. "Before-after" collection of vital signs, recording of daily sedative drug consumption and measurement of stress and inflammatory blood markers were performed. Of 55 randomized patients, 49 were included in the final analyses. Along with music listening, (i) vital signs did not consistently change, whereas narcotic consumption tended to decrease to a similar sedation (P = .06 vs sham-MP3); (ii) cortisol and prolactin blood concentrations decreased, whereas Adreno Cortico Trophic Hormone (ACTH)/cortisol ratio increased (P = .02; P = .038; and P = .015 vs sham-MP3, respectively), (iii) cortisol responders exhibited reversed associated changes in blood mehionine (MET)-enkephalin content (P = .01). In the present trial, music listening is a more sensitive stress-reliever in terms of biological vs clinical response. The hypothalamus-pituitary adrenal axis stress axis is a quick sensor of music listening in responding mechanically ventilated intensive care unit patients, through a rapid reduction in blood cortisol. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Experimental blunt chest trauma--cardiorespiratory effects of different mechanical ventilation strategies with high positive end-expiratory pressure: a randomized controlled study.

    Science.gov (United States)

    Schreiter, Dierk; Carvalho, Nadja C; Katscher, Sebastian; Mende, Ludger; Reske, Alexander P; Spieth, Peter M; Carvalho, Alysson R; Beda, Alessandro; Lachmann, Burkhard; Amato, Marcelo B P; Wrigge, Hermann; Reske, Andreas W

    2016-01-12

    Uncertainty persists regarding the optimal ventilatory strategy in trauma patients developing acute respiratory distress syndrome (ARDS). This work aims to assess the effects of two mechanical ventilation strategies with high positive end-expiratory pressure (PEEP) in experimental ARDS following blunt chest trauma. Twenty-six juvenile pigs were anesthetized, tracheotomized and mechanically ventilated. A contusion was applied to the right chest using a bolt-shot device. Ninety minutes after contusion, animals were randomized to two different ventilation modes, applied for 24 h: Twelve pigs received conventional pressure-controlled ventilation with moderately low tidal volumes (VT, 8 ml/kg) and empirically chosen high external PEEP (16 cmH2O) and are referred to as the HP-CMV-group. The other group (n = 14) underwent high-frequency inverse-ratio pressure-controlled ventilation (HFPPV) involving respiratory rate of 65 breaths · min(-1), inspiratory-to-expiratory-ratio 2:1, development of intrinsic PEEP and recruitment maneuvers, compatible with the rationale of the Open Lung Concept. Hemodynamics, gas exchange and respiratory mechanics were monitored during 24 h. Computed tomography and histology were analyzed in subgroups. Comparing changes which occurred from randomization (90 min after chest trauma) over the 24-h treatment period, groups differed statistically significantly (all P values for group effect ventilation improved respiratory function and fulfilled relevant ventilation endpoints for trauma patients, i.e. restoration of oxygenation and lung aeration while avoiding hypercapnia and respiratory acidosis.

  17. Terminating Sequential Delphi Survey Data Collection

    Science.gov (United States)

    Kalaian, Sema A.; Kasim, Rafa M.

    2012-01-01

    The Delphi survey technique is an iterative mail or electronic (e-mail or web-based) survey method used to obtain agreement or consensus among a group of experts in a specific field on a particular issue through a well-designed and systematic multiple sequential rounds of survey administrations. Each of the multiple rounds of the Delphi survey…

  18. Bringing sequential feature explanations to life

    CSIR Research Space (South Africa)

    Mokoena, Tshepiso

    2017-09-01

    Full Text Available with no information about what caused the anomalies. A sequential feature explanation(SFE) of a detected data point is an ordered sequence of features which are presented to the analysts, one at a time until the information contained in the set of already presented...

  19. Sequential auctions for full truckload allocation

    NARCIS (Netherlands)

    Mes, Martijn R.K.

    2008-01-01

    In this thesis we examine the use of sequential auctions for the dynamic allocation of transportation jobs. For all players, buyers and sellers, we develop strategies and examine their performance both in terms of individual benefits and with respect to the global logistical performance (resource

  20. Hierarchical Knowledge Gradient for Sequential Sampling

    NARCIS (Netherlands)

    Mes, Martijn R.K.; Powell, Warren B.; Frazier, Peter I.

    2011-01-01

    We propose a sequential sampling policy for noisy discrete global optimization and ranking and selection, in which we aim to efficiently explore a finite set of alternatives before selecting an alternative as best when exploration stops. Each alternative may be characterized by a multidimensional

  1. Sequential Bayesian technique: An alternative approach for ...

    Indian Academy of Sciences (India)

    This paper proposes a sequential Bayesian approach similar to Kalman filter for estimating reliability growth or decay of software. The main advantage of proposed method is that it shows the variation of the parameter over a time, as new failure data become available. The usefulness of the method is demonstrated with ...

  2. The curse of sequentiality in routing games

    NARCIS (Netherlands)

    Correa, José; de Jong, Jasper; de Keijzer, Bart; Uetz, Marc Jochen; Markakis, Evangelos; Schäfer, Guido

    2015-01-01

    In the "The curse of simultaneity", Paes Leme at al. show that there are interesting classes of games for which sequential decision making and corresponding subgame perfect equilibria avoid worst case Nash equilibria, resulting in substantial improvements for the price of anarchy. This is called the

  3. Sequential Bayesian technique: An alternative approach for ...

    Indian Academy of Sciences (India)

    MS received 8 October 2007; revised 15 July 2008. Abstract. This paper proposes a sequential Bayesian approach similar to Kalman filter for estimating reliability growth or decay of software. The main advantage of proposed method is that it shows the variation of the parameter over a time, as new failure data become ...

  4. Sequential and Simultaneous Logit: A Nested Model.

    NARCIS (Netherlands)

    van Ophem, J.C.M.; Schram, A.J.H.C.

    1997-01-01

    A nested model is presented which has both the sequential and the multinomial logit model as special cases. This model provides a simple test to investigate the validity of these specifications. Some theoretical properties of the model are discussed. In the analysis a distribution function is

  5. Adult Word Recognition and Visual Sequential Memory

    Science.gov (United States)

    Holmes, V. M.

    2012-01-01

    Two experiments were conducted investigating the role of visual sequential memory skill in the word recognition efficiency of undergraduate university students. Word recognition was assessed in a lexical decision task using regularly and strangely spelt words, and nonwords that were either standard orthographically legal strings or items made from…

  6. A Scalable Algorithm for Clustering Sequential Data

    Science.gov (United States)

    2001-08-16

    can be computed e cient using a variety of sequential pattern discovery algorithms AS SA Zak JKK HPMA Projecting in to the Feature...matrices from protein blocks Proc Natl Academy Science HPMA J Han J Pei B MortazaviAsl Q Chen U Dayal and M

  7. Sequential male mate choice under sperm competition risk.

    Science.gov (United States)

    Ramm, Steven A; Stockley, Paula

    2014-05-01

    Male eagerness to mate is a central paradigm of sexual selection theory. However, limited sperm supplies mean that male sexual restraint might sometimes be favored under promiscuous mating. Here, we demonstrate dynamic plasticity in male mating effort when females are encountered sequentially under varying sperm competition risk. Rather than showing consistent eagerness to mate, male house mice (Mus musculus domesticus) instead tailor their mating effort according to likely reproductive payoffs. They are significantly less likely to mate when sperm competition is certain and potential reproductive payoffs low, but dramatically increase investment if they do choose to mate under such circumstances. By contrast, male mice are significantly more likely to mate in situations simulating extra-territorial copulations, where future risk of competition is high but so too are potential reproductive rewards. Differential mating propensity appears to be the primary mechanism by which male house mice allocate sperm adaptively under sperm competition risk because we find no evidence for facultative adjustment of sperm numbers per ejaculate or ejaculation frequency in response to female-related cues. We conclude that sequential male mate choice under sperm competition risk could be a widespread but often unappreciated mechanism of strategic sperm allocation.

  8. Tinnitus after Simultaneous and Sequential Bilateral Cochlear Implantation

    Directory of Open Access Journals (Sweden)

    Geerte G. J. Ramakers

    2017-11-01

    Full Text Available ImportanceThere is an ongoing global discussion on whether or not bilateral cochlear implantation should be standard care for bilateral deafness. Contrary to unilateral cochlear implantation, however, little is known about the effect of bilateral cochlear implantation on tinnitus.ObjectiveTo investigate tinnitus outcomes 1 year after bilateral cochlear implantation. Secondarily, to compare tinnitus outcomes between simultaneous and sequential bilateral cochlear implantation and to investigate long-term follow-up (3 years.Study designThis study is a secondary analysis as part of a multicenter randomized controlled trial.MethodsThirty-eight postlingually deafened adults were included in the original trial, in which the presence of tinnitus was not an inclusion criterion. All participants received cochlear implants (CIs because of profound hearing loss. Nineteen participants received bilateral CIs simultaneously and 19 participants received bilateral CIs sequentially with an inter-implant interval of 2 years. The prevalence and severity of tinnitus before and after simultaneous and sequential bilateral cochlear implantation were measured preoperatively and each year after implantation with the Tinnitus Handicap Inventory (THI and Tinnitus Questionnaire (TQ.ResultsThe prevalence of preoperative tinnitus was 42% (16/38. One year after bilateral implantation, there was a median difference of −8 (inter-quartile range (IQR: −28 to 4 in THI score and −9 (IQR: −17 to −9 in TQ score in the participants with preoperative tinnitus. Induction of tinnitus occurred in five participants, all in the simultaneous group, in the year after bilateral implantation. Although the preoperative and also the postoperative median THI and TQ scores were higher in the simultaneous group, the median difference scores were equal in both groups. In the simultaneous group, tinnitus scores fluctuated in the 3 years after implantation. In the sequential group

  9. A fast and accurate online sequential learning algorithm for feedforward networks.

    Science.gov (United States)

    Liang, Nan-Ying; Huang, Guang-Bin; Saratchandran, P; Sundararajan, N

    2006-11-01

    In this paper, we develop an online sequential learning algorithm for single hidden layer feedforward networks (SLFNs) with additive or radial basis function (RBF) hidden nodes in a unified framework. The algorithm is referred to as online sequential extreme learning machine (OS-ELM) and can learn data one-by-one or chunk-by-chunk (a block of data) with fixed or varying chunk size. The activation functions for additive nodes in OS-ELM can be any bounded nonconstant piecewise continuous functions and the activation functions for RBF nodes can be any integrable piecewise continuous functions. In OS-ELM, the parameters of hidden nodes (the input weights and biases of additive nodes or the centers and impact factors of RBF nodes) are randomly selected and the output weights are analytically determined based on the sequentially arriving data. The algorithm uses the ideas of ELM of Huang et al. developed for batch learning which has been shown to be extremely fast with generalization performance better than other batch training methods. Apart from selecting the number of hidden nodes, no other control parameters have to be manually chosen. Detailed performance comparison of OS-ELM is done with other popular sequential learning algorithms on benchmark problems drawn from the regression, classification and time series prediction areas. The results show that the OS-ELM is faster than the other sequential algorithms and produces better generalization performance.

  10. ARQ with sequential decoding of packetized data - Queueing analysis

    Science.gov (United States)

    Shacham, N.

    1984-10-01

    The operation of a sequential decoder in a packet-switching environment is considered. Packets arrive randomly at the decoder, and a packet is stored in a buffer if the decoder is busy upon its arrival. The decoder devotes no more than a time-out period of predetermined length to the decoding of any single packet. If packet decoding is completed within that period, the packet leaves the system. Otherwise, it is retransmitted and its decoding starts anew. While a packet is retransmitted, the decoder decodes another packet that resides in its buffer. An upper bound on the maximum rate of packets that can be supported by the channel-decoder combination is derived, and the optimum time-out that maximizes that rate is determined. A discrete-time model of the decoder's queue is presented, and the average queue length and throughput are evaluated.

  11. Sequential Antibiotic Therapy: Effective Cost Management and Patient Care

    Directory of Open Access Journals (Sweden)

    Lionel A Mandell

    1995-01-01

    Full Text Available The escalating costs associated with antimicrobial chemotherapy have become of increasing concern to physicians, pharmacists and patients alike. A number of strategies have been developed to address this problem. This article focuses specifically on sequential antibiotic therapy (sat, which is the strategy of converting patients from intravenous to oral medication regardless of whether the same or a different class of drug is used. Advantages of sat include economic benefits, patient benefits and benefits to the health care provider. Potential disadvantages are cost to the consumer and the risk of therapeutic failure. A critical review of the published literature shows that evidence from randomized controlled trials supports the role of sat. However, it is also clear that further studies are necessary to determine the optimal time for intravenous to oral changeover and to identify the variables that may interfere with the use of oral drugs. Procedures necessary for the implementation of a sat program in the hospital setting are also discussed.

  12. Variable versus conventional lung protective mechanical ventilation during open abdominal surgery: study protocol for a randomized controlled trial

    OpenAIRE

    Spieth, Peter M; Güldner, Andreas; Uhlig, Christopher; Bluth, Thomas; Kiss, Thomas; Schultz, Marcus J.; Pelosi, Paolo; Koch, Thea; Gama de Abreu, Marcelo

    2014-01-01

    Background General anesthesia usually requires mechanical ventilation, which is traditionally accomplished with constant tidal volumes in volume- or pressure-controlled modes. Experimental studies suggest that the use of variable tidal volumes (variable ventilation) recruits lung tissue, improves pulmonary function and reduces systemic inflammatory response. However, it is currently not known whether patients undergoing open abdominal surgery might benefit from intraoperative variable ventila...

  13. Investigating the mechanisms of hallucinogen-induced visions using 3,4-methylenedioxyamphetamine (MDA: a randomized controlled trial in humans.

    Directory of Open Access Journals (Sweden)

    Matthew J Baggott

    2010-12-01

    Full Text Available The mechanisms of drug-induced visions are poorly understood. Very few serotonergic hallucinogens have been studied in humans in decades, despite widespread use of these drugs and potential relevance of their mechanisms to hallucinations occurring in psychiatric and neurological disorders.We investigated the mechanisms of hallucinogen-induced visions by measuring the visual and perceptual effects of the hallucinogenic serotonin 5-HT2AR receptor agonist and monoamine releaser, 3,4-methylenedioxyamphetamine (MDA, in a double-blind placebo-controlled study. We found that MDA increased self-report measures of mystical-type experience and other hallucinogen-like effects, including reported visual alterations. MDA produced a significant increase in closed-eye visions (CEVs, with considerable individual variation. Magnitude of CEVs after MDA was associated with lower performance on measures of contour integration and object recognition.Drug-induced visions may have greater intensity in people with poor sensory or perceptual processing, suggesting common mechanisms with other hallucinatory syndromes. MDA is a potential tool to investigate mystical experiences and visual perception.Clinicaltrials.gov NCT00823407.

  14. Effects that passive cycling exercise have on muscle strength, duration of mechanical ventilation, and length of hospital stay in critically ill patients: a randomized clinical trial

    Science.gov (United States)

    Machado, Aline dos Santos; Pires-Neto, Ruy Camargo; Carvalho, Maurício Tatsch Ximenes; Soares, Janice Cristina; Cardoso, Dannuey Machado; de Albuquerque, Isabella Martins

    2017-01-01

    ABSTRACT Objective: To evaluate the effects that passive cycling exercise, in combination with conventional physical therapy, have on peripheral muscle strength, duration of mechanical ventilation, and length of hospital stay in critically ill patients admitted to the ICU of a tertiary care university hospital. Methods: This was a randomized clinical trial involving 38 patients (≥ 18 years of age) on mechanical ventilation who were randomly divided into two groups: control (n = 16), receiving conventional physical therapy; and intervention (n = 22), receiving conventional physical therapy and engaging in passive cycling exercise five days per week. The mean age of the patients was 46.42 ± 16.25 years, and 23 were male. The outcomes studied were peripheral muscle strength, as measured by the Medical Research Council scale, duration of mechanical ventilation, and length of hospital stay. Results: There was a significant increase in peripheral muscle strength (baseline vs. final) in both groups (control: 40.81 ± 7.68 vs. 45.00 ± 6.89; and intervention: 38.73 ± 11.11 vs. 47.18 ± 8.75; p < 0.001 for both). However, the range of increase in strength was higher in the intervention group than in the control group (8.45 ± 5.20 vs. 4.18 ± 2.63; p = 0.005). There were no significant differences between the groups in terms of duration of mechanical ventilation or length of hospital stay. Conclusions: The results suggest that the performance of continuous passive mobilization on a cyclical basis helps to recover peripheral muscle strength in ICU patients. (ClinicalTrials.gov Identifier: NCT01769846 [http://www.clinicaltrials.gov/]) PMID:28538781

  15. Mendelian Randomization Implicates High-Density Lipoprotein Cholesterol-Associated Mechanisms in Etiology of Age-Related Macular Degeneration.

    Science.gov (United States)

    Burgess, Stephen; Davey Smith, George

    2017-08-01

    Undertake a systematic investigation into associations between genetic predictors of lipid fractions and age-related macular degeneration (AMD) risk. Two-sample Mendelian randomization investigation using published data. A total of 33 526 individuals (16 144 cases, 17 832 controls) predominantly of European ancestry from the International Age-related Macular Degeneration Genomics Consortium. We consider 185 variants previously demonstrated to be associated with at least 1 of low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, or triglycerides at a genome-wide level of significance, and test their associations with AMD. We particularly focus on variants in gene regions that are proxies for specific pharmacologic agents for lipid therapy. We then conduct a 2-sample Mendelian randomization investigation to assess the causal roles of LDL-cholesterol, HDL-cholesterol, and triglycerides on AMD risk. We also conduct parallel investigations for coronary artery disease (CAD) (viewed as a positive control) and Alzheimer's disease (a negative control) for comparison. Diagnosis of AMD. We find evidence that HDL-cholesterol is a causal risk factor for AMD, with an odds ratio (OR) estimate of 1.22 (95% confidence interval [CI], 1.03-1.44) per 1 standard deviation increase in HDL-cholesterol. No causal effect of LDL-cholesterol or triglycerides was found. Variants in the CETP gene region associated with increased circulating HDL-cholesterol also associate with increased AMD risk, although variants in the LIPC gene region that increase circulating HDL-cholesterol have the opposite direction of association with AMD risk. Parallel analyses suggest that lipids have a greater role for AMD compared with Alzheimer's disease, but a lesser role than for CAD. Some genetic evidence suggests that HDL-cholesterol is a causal risk factor for AMD risk and that increasing HDL-cholesterol (particularly via CETP inhibition) will increase AMD risk

  16. Prospective randomized crossover study of a new closed-loop control system versus pressure support during weaning from mechanical ventilation.

    Science.gov (United States)

    Clavieras, Noémie; Wysocki, Marc; Coisel, Yannael; Galia, Fabrice; Conseil, Matthieu; Chanques, Gerald; Jung, Boris; Arnal, Jean-Michel; Matecki, Stefan; Molinari, Nicolas; Jaber, Samir

    2013-09-01

    Intellivent is a new full closed-loop controlled ventilation that automatically adjusts both ventilation and oxygenation parameters. The authors compared gas exchange and breathing pattern variability of Intellivent and pressure support ventilation (PSV). In a prospective, randomized, single-blind design crossover study, 14 patients were ventilated during the weaning phase, with Intellivent or PSV, for two periods of 24 h in a randomized order. Arterial blood gases were obtained after 1, 8, 16, and 24 h with each mode. Ventilatory parameters were recorded continuously in a breath-by-breath basis during the two study periods. The primary endpoint was oxygenation, estimated by the calculation of the difference between the PaO2/FIO2 ratio obtained after 24 h of ventilation and the PaO2/FIO2 ratio obtained at baseline in each mode. The variability in the ventilatory parameters was also evaluated by the coefficient of variation (SD to mean ratio). There were no adverse events or safety issues requiring premature interruption of both modes. The PaO2/FIO2 (mean ± SD) ratio improved significantly from 245 ± 75 at baseline to 294 ± 123 (P = 0.03) after 24 h of Intellivent. The coefficient of variation of inspiratory pressure and positive end-expiratory pressure (median [interquartile range]) were significantly higher with Intellivent, 16 [11-21] and 15 [7-23]%, compared with 6 [5-7] and 7 [5-10]% in PSV. Inspiratory pressure, positive end-expiratory pressure, and FIO2 changes were adjusted significantly more often with Intellivent compared with PSV. Compared with PSV, Intellivent during a 24-h period improved the PaO2/FIO2 ratio in parallel with more variability in the ventilatory support and more changes in ventilation settings.

  17. A prospective randomized controlled blinded study of three bronchodilators in infants with respiratory syncytial virus bronchiolitis on mechanical ventilation.

    Science.gov (United States)

    Levin, Daniel L; Garg, Abhinav; Hall, Leila J; Slogic, Scott; Jarvis, J Dean; Leiter, James C

    2008-11-01

    To study patients with respiratory syncytial virus bronchiolitis in respiratory failure to make specific measurements reflecting airway resistance before and after treatment with commonly used agents. We hypothesized that racemic epinephrine would decrease airways resistance more effectively than levalbuterol, and levalbuterol would decrease airways resistance more effectively than racemic albuterol. Normal saline was used as a control. Prospective, randomized, controlled, blinded study. Tertiary Pediatric Intensive Care Unit in a University affiliated hospital in the northeastern United States. Twenty-two patients with respiratory syncytial virus bronchiolitis and in respiratory failure were enrolled. All were intubated and ventilated in a volume control mode and sedated. In a randomized, blinded fashion patients were given four agents: norepinephrine, levalbuterol, racemic albuterol, and normal saline at 6 hr intervals. As indicators of bronchodilation, peak inspiratory pressure and inspiratory respiratory system resistance were measured before and 20 mins after each agent was given. Thus, each patient acted as his/her own control. There were small but statistically significant decreases in peak inspiratory pressure after racemic epinephrine treatment, levalbuterol, and racemic albuterol. There was no change in peak inspiratory pressure after inhaled normal saline. Inspiratory respiratory system resistance fell significantly after all treatments, including saline. Heart rate rose significantly after inhaled bronchodilator treatments (p < 0.05 for all treatments). Similar statistically significant bronchodilation occurred after all three bronchodilators as indicated by a decrease in peak inspiratory pressure and respiratory system resistance, but these changes were small and probably clinically insignificant. However, side effects of bronchodilators, such as tachycardia, also occurred, and these may be clinically significant. Thus the benefit of bronchodilator

  18. Laser peripheral iridotomy versus laser peripheral iridotomy plus laser peripheral iridoplasty in the treatment of multi-mechanism angle closure: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Chen, Shida; Lv, Jianhua; Fan, Sujie; Zhang, Hong; Xie, Lin; Xu, Ling; Jiang, Bing; Yuan, Huipin; Liang, Yuanbo; Li, Shuning; Chen, Pingyan; Zhang, Xiulan; Wang, Ningli

    2017-03-17

    China has the largest burden of primary angle-closure glaucoma (PACG) worldwide. The mechanism of the angle closure is complex and includes pupillary block and non-pupillary block. Currently, opinion is that laser peripheral iridotomy (LPI) alone is not sufficient to prevent disease progression. Laser peripheral iridoplasty (LPIP) is an alternative and effective way of widening the angle recess in eyes that are affected by primary angle closure (PAC). However, it is not known if greater benefit would be achieved using LPI plus LPIP for PAC with multiple mechanisms (MAC). Thus, the aim of this study is to demonstrate if LPI plus LPIP would be more effective than single LPI in controlling the progression of PAC with multiple mechanisms, based on ultrasound biomicroscopy (UBM) classification. A secondary aim is to determine whether or not this would result in the use of less medication and/or prolong the time to antiglaucoma surgery. This multiple-mechanism angle-closure study will comprise a 3-year, multicenter, randomized, parallel-group, open-label, superiority trial, the aim of which will be to evaluate the safety and efficacy of LPI plus LPIP versus LPI for PAC. It is anticipated that 240 adults, diagnosed with PAC (the mechanism of angle closure will be assessed by UBM and it will be determined whether or not it involves multiple mechanisms) will be recruited from ten ophthalmic centers in China. Participants will be randomly allocated to receive either single LPI or LPI plus LPIP. Participant assessment will be designed to test the rate of disease progression and who will be followed up for 3 years. The primary outcome will be the disease progression rate and a comparison will be made between the LPI and LPI plus LPIP groups using Pearson's χ 2 test. Logistic regression analysis will be performed to account for the central effect. If the LPI plus LPIP is found to significantly decrease the rate of PAC progression, this intervention could potentially be a

  19. Release of growth factors after mechanical and chemical pleurodesis for treatment of malignant pleural effusion: a randomized control study

    Directory of Open Access Journals (Sweden)

    Hojski Aljaz

    2015-12-01

    Full Text Available Background. Growth factors are key inducers of fibrosis but can also mediate inflammatory responses resulting in increasing pleural effusion and acute respiratory distress syndrome. The primary aim of the study was to analyse growth factors release after performing chemical and mechanical pleurodesis in the first 48 hours at the patients with malignant pleural effusion. The secondary endpoints were to evaluate the effectiveness of the both pleurodeses, symptoms release and the quality of life of patients after the treatment.

  20. Upper cervical and upper thoracic thrust manipulation versus nonthrust mobilization in patients with mechanical neck pain: a multicenter randomized clinical trial.

    Science.gov (United States)

    Dunning, James R; Cleland, Joshua A; Waldrop, Mark A; Arnot, Cathy F; Young, Ian A; Turner, Michael; Sigurdsson, Gisli

    2012-01-01

    Randomized clinical trial. To compare the short-term effects of upper cervical and upper thoracic high-velocity low-amplitude (HVLA) thrust manipulation to nonthrust mobilization in patients with neck pain. Although upper cervical and upper thoracic HVLA thrust manipulation and nonthrust mobilization are common interventions for the management of neck pain, no studies have directly compared the effects of both upper cervical and upper thoracic HVLA thrust manipulation to nonthrust mobilization in patients with neck pain. Patients completed the Neck Disability Index, the numeric pain rating scale, the flexion-rotation test for measurement of C1-2 passive rotation range of motion, and the craniocervical flexion test for measurement of deep cervical flexor motor performance. Following the baseline evaluation, patients were randomized to receive either HVLA thrust manipulation or nonthrust mobilization to the upper cervical (C1-2) and upper thoracic (T1-2) spines. Patients were reexamined 48-hours after the initial examination and again completed the outcome measures. The effects of treatment on disability, pain, C1-2 passive rotation range of motion, and motor performance of the deep cervical flexors were examined with a 2-by-2 mixed-model analysis of variance (ANOVA). One hundred seven patients satisfied the eligibility criteria, agreed to participate, and were randomized into the HVLA thrust manipulation (n = 56) and nonthrust mobilization (n = 51) groups. The 2-by-2 ANOVA demonstrated that patients with mechanical neck pain who received the combination of upper cervical and upper thoracic HVLA thrust manipulation experienced significantly (Ppain (58.5%) than those of the nonthrust mobilization group (12.8% and 12.6%, respectively) following treatment. In addition, the HVLA thrust manipulation group had significantly (PNeck Disability Index cut scores, respectively. The combination of upper cervical and upper thoracic HVLA thrust manipulation is appreciably more

  1. Remifentanil/midazolam versus fentanyl/midazolam for analgesia and sedation of mechanically ventilated neonates and young infants: a randomized controlled trial.

    Science.gov (United States)

    Welzing, Lars; Oberthuer, Andre; Junghaenel, Shino; Harnischmacher, Urs; Stützer, Hartmut; Roth, Bernhard

    2012-06-01

    Common opioids for analgesia and sedation of mechanically ventilated infants may tend to accumulate and cause prolonged sedation with an unpredictable extubation time. Remifentanil is a promising option due to its unique pharmacokinetic properties, which seem to be valid in adults as well as in infants. In this double-blind, randomized, controlled trial mechanically ventilated neonates and young infants (sedation regimen with low dose midazolam. The primary endpoint of the trial was the extubation time following discontinuation of the opioid infusion. Secondary endpoints included efficacy and safety aspects. Between November 2006 and March 2010, we screened 431 mechanically ventilated infants for eligibility. The intention to treat group included 23 infants who were assigned to receive either remifentanil (n = 11) or fentanyl (n = 12). Although this was designed as a pilot study, median extubation time was significantly shorter in the remifentanil group (80.0 min, IQR = 15.0-165.0) compared to the fentanyl group (782.5 min, IQR = 250.8-1,875.0) (p = 0.005). Remifentanil and fentanyl provided comparable efficacy with more than two-thirds of the measurements indicating optimal analgesia and sedation (66.4 and 70.2 %, respectively; p = 0.743). Overall, both groups had good hemodynamic stability and a comparably low incidence of adverse events. As neonates and young infants have a decreased metabolism of common opioids like fentanyl and are more prone to respiratory depression, remifentanil could be the ideal opioid for analgesia and sedation of mechanically ventilated infants.

  2. A randomized clinical trial of neurally adjusted ventilatory assist versus conventional weaning mode in patients with COPD and prolonged mechanical ventilation.

    Science.gov (United States)

    Kuo, Nai-Ying; Tu, Mei-Lien; Hung, Tsai-Yi; Liu, Shih-Feng; Chung, Yu-Hsiu; Lin, Meng-Chih; Wu, Chao-Chien

    2016-01-01

    Patient-ventilator asynchrony is a common problem in mechanically ventilated patients; the problem is especially obvious in COPD. Neutrally adjusted ventilatory assist (NAVA) can improve patient-ventilator asynchrony; however, the effect in COPD patients with prolonged mechanical ventilation is still unknown. The goals of this study are to evaluate the effect of NAVA and conventional weaning mode in patients with COPD during prolonged mechanical ventilation. The study enrolled a total of 33 COPD patients with ventilator dependency for more than 21 days in the weaning center. A diaphragm electrical activity (Edi) catheter was inserted in patients within 24 hours after admission to the respiratory care center, and patients were randomly allocated to NAVA or conventional group. A spontaneous breathing trial was performed every 24 hours. The results correlated with the clinical parameters. There were significantly higher asynchrony incidence rates in the whole group after using Edi catheter (before vs post-Edi catheter insertion =60.6% vs 87.9%, Ppatient-ventilator interaction in COPD patients with prolonged mechanical ventilation in respiratory care center.

  3. Rationalizing Boundedly Rational Choice : Sequential Rationalizability and Rational Shortlist Methods

    OpenAIRE

    Manzini, Paola; Mariotti, Marco

    2004-01-01

    A sequentially rationalizable choice function is a choice function which can be obtained by applying sequentially a fixed set of asymmetric binary relations (rationales). A Rational ShortlistMethod (RSM) is a choice function which is sequentially rationalizable by two rationales. These concepts translate into economic language some human choice heuristics studied in psychology. We provide a full characterization of RSMs and study some properties of sequential rationalizability. These properti...

  4. Sequential shrink photolithography for plastic microlens arrays

    Science.gov (United States)

    Dyer, David; Shreim, Samir; Jayadev, Shreshta; Lew, Valerie; Botvinick, Elliot; Khine, Michelle

    2011-07-01

    Endeavoring to push the boundaries of microfabrication with shrinkable polymers, we have developed a sequential shrink photolithography process. We demonstrate the utility of this approach by rapidly fabricating plastic microlens arrays. First, we create a mask out of the children's toy Shrinky Dinks by simply printing dots using a standard desktop printer. Upon retraction of this pre-stressed thermoplastic sheet, the dots shrink to a fraction of their original size, which we then lithographically transfer onto photoresist-coated commodity shrink wrap film. This shrink film reduces in area by 95% when briefly heated, creating smooth convex photoresist bumps down to 30 µm. Taken together, this sequential shrink process provides a complete process to create microlenses, with an almost 99% reduction in area from the original pattern size. Finally, with a lithography molding step, we emboss these bumps into optical grade plastics such as cyclic olefin copolymer for functional microlens arrays.

  5. Sequential motif profile of natural visibility graphs

    Science.gov (United States)

    Iacovacci, Jacopo; Lacasa, Lucas

    2016-11-01

    The concept of sequential visibility graph motifs—subgraphs appearing with characteristic frequencies in the visibility graphs associated to time series—has been advanced recently along with a theoretical framework to compute analytically the motif profiles associated to horizontal visibility graphs (HVGs). Here we develop a theory to compute the profile of sequential visibility graph motifs in the context of natural visibility graphs (VGs). This theory gives exact results for deterministic aperiodic processes with a smooth invariant density or stochastic processes that fulfill the Markov property and have a continuous marginal distribution. The framework also allows for a linear time numerical estimation in the case of empirical time series. A comparison between the HVG and the VG case (including evaluation of their robustness for short series polluted with measurement noise) is also presented.

  6. On the error probability of general tree and trellis codes with applications to sequential decoding

    Science.gov (United States)

    Johannesson, R.

    1973-01-01

    An upper bound on the average error probability for maximum-likelihood decoding of the ensemble of random binary tree codes is derived and shown to be independent of the length of the tree. An upper bound on the average error probability for maximum-likelihood decoding of the ensemble of random L-branch binary trellis codes of rate R = 1/n is derived which separates the effects of the tail length T and the memory length M of the code. It is shown that the bound is independent of the length L of the information sequence. This implication is investigated by computer simulations of sequential decoding utilizing the stack algorithm. These simulations confirm the implication and further suggest an empirical formula for the true undetected decoding error probability with sequential decoding.

  7. Sequential shrink photolithography for plastic microlens arrays

    OpenAIRE

    Dyer, D; Shreim, S; Jayadev, S; Lew, V; Botvinick, E; Khine, M

    2011-01-01

    Endeavoring to push the boundaries of microfabrication with shrinkable polymers, we have developed a sequential shrink photolithography process. We demonstrate the utility of this approach by rapidly fabricating plastic microlens arrays. First, we create a mask out of the children's toy Shrinky Dinks by simply printing dots using a standard desktop printer. Upon retraction of this pre-stressed thermoplastic sheet, the dots shrink to a fraction of their original size, which we then lithographi...

  8. On Delayed Sequential Coding of Correlated Sources

    OpenAIRE

    Ma, Nan; Wang, Ye; Ishwar, Prakash

    2007-01-01

    Motivated by video coding applications, the problem of sequential coding of correlated sources with encoding and/or decoding frame-delays is studied. The fundamental tradeoffs between individual frame rates, individual frame distortions, and encoding/decoding frame-delays are derived in terms of a single-letter information-theoretic characterization of the rate-distortion region for general inter-frame source correlations and certain types of potentially frame specific and coupled single-lett...

  9. Sequential decision analysis for nonstationary stochastic processes

    Science.gov (United States)

    Schaefer, B.

    1974-01-01

    A formulation of the problem of making decisions concerning the state of nonstationary stochastic processes is given. An optimal decision rule, for the case in which the stochastic process is independent of the decisions made, is derived. It is shown that this rule is a generalization of the Bayesian likelihood ratio test; and an analog to Wald's sequential likelihood ratio test is given, in which the optimal thresholds may vary with time.

  10. Sequential Medical Trials Involving Paired Data.

    Science.gov (United States)

    1979-05-22

    solution exists for this sequential decision problem if it is posed in a Bayesian framework with ~i being given a prior norma l 2distribution with mean and...AOOREU ‘-‘- ~~ OIT SAT E Office of Naval Research ‘~“ J~~ May ~~ ~~79Statistics & Prthabi1i~y Progran Code 436 ~‘ ~~~~~~ FAISSS—ii

  11. Analysis on Realization of Sequential Queue

    Science.gov (United States)

    Wang, Min

    Analyzed and introduced the sequential storage structure of the queue, detailed analyzed several specific methods for the circular queue to resolve the "false overflow", gave the algorithm descriptions in C of the corresponding basic operations of the queue, compared and analyzed each algorithm the time complexity and the space complexity, so as to complement and play a guiding role in the relevant chapters in "Data Structure" curriculum.

  12. Lung Volume Measured during Sequential Swallowing in Healthy Young Adults

    Science.gov (United States)

    Hegland, Karen Wheeler; Huber, Jessica E.; Pitts, Teresa; Davenport, Paul W.; Sapienza, Christine M.

    2011-01-01

    Purpose: Outcomes from studying the coordinative relationship between respiratory and swallow subsystems are inconsistent for sequential swallows, and the lung volume at the initiation of sequential swallowing remains undefined. The first goal of this study was to quantify the lung volume at initiation of sequential swallowing ingestion cycles and…

  13. Incorporation of mesoporous silica nanoparticles into random electrospun PLGA and PLGA/gelatin nanofibrous scaffolds enhances mechanical and cell proliferation properties

    Energy Technology Data Exchange (ETDEWEB)

    Mehrasa, Mohammad [Department of Biotechnology, Faculty of Advanced Sciences and Technologies, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of); Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology, Tehran (Iran, Islamic Republic of); Asadollahi, Mohammad Ali, E-mail: ma.asadollahi@ast.ui.ac.ir [Department of Biotechnology, Faculty of Advanced Sciences and Technologies, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of); Nasri-Nasrabadi, Bijan [Department of Chemical Engineering, Isfahan University of Technology, Isfahan (Iran, Islamic Republic of); Ghaedi, Kamran [Department of Biology, Faculty of Science, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of); Salehi, Hossein [Department of Anatomical Sciences, School of Medicine, Isfahan University of Medical Sciences, Isfahan (Iran, Islamic Republic of); Dolatshahi-Pirouz, Alireza [DTU Nanotech, Center for Nanomedicine and Theranostics, Technical University of Denmark (DTU), DK-2800 Kgs. Lyngby (Denmark); Arpanaei, Ayyoob, E-mail: arpanaei@yahoo.com [Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology, Tehran (Iran, Islamic Republic of)

    2016-09-01

    Poly(lactic-co-glycolic acid) (PLGA) and PLGA/gelatin random nanofibrous scaffolds embedded with different amounts of mesoporous silica nanoparticles (MSNPs) were fabricated using electrospinning method. To evaluate the effects of nanoparticles on the scaffolds, physical, chemical, and mechanical properties as well as in vitro degradation behavior of scaffolds were investigated. The mean diameters of nanofibers were 974 ± 68 nm for the pure PLGA scaffolds vs 832 ± 70, 764 ± 80, and 486 ± 64 for the PLGA/gelatin, PLGA/10 wt% MSNPs, and the PLGA/gelatin/10 wt% MSNPs scaffolds, respectively. The results suggested that the incorporation of gelatin and MSNPs into PLGA-based scaffolds enhances the hydrophilicity of scaffolds due to an increase of hydrophilic functional groups on the surface of nanofibers. With porosity examination, it was concluded that the incorporation of MSNPs and gelatin decrease the porosity of scaffolds. Nanoparticles also improved the tensile mechanical properties of scaffolds. Using in vitro degradation analysis, it was shown that the addition of nanoparticles to the nanofibers matrix increases the weight loss percentage of PLGA-based samples, whereas it decreases the weight loss percentage in the PLGA/gelatin composites. Cultivation of rat pheochromocytoma cell line (PC12), as precursor cells of dopaminergic neural cells, on the scaffolds demonstrated that the introduction of MSNPs into PLGA and PLGA/gelatin matrix leads to improved cell attachment and proliferation and enhances cellular processes. - Highlights: • PLGA-based random nanofibers embedded with mesoporous silica nanoparticles were fabricated using electrospinning method • Incorporation of gelatin and MSNPs into PLGA-based scaffolds increased the hydrophilicity of scaffold • Addition of nanoparticles also improved the tensile mechanical properties of scaffolds • Introduction of MSNPs led to improved cell attachment and proliferation.

  14. Transition from nonsequential to sequential double ionization in many-electron systems

    Science.gov (United States)

    Pullen, Michael G.; Wolter, Benjamin; Wang, Xu; Tong, Xiao-Min; Sclafani, Michele; Baudisch, Matthias; Pires, Hugo; Schröter, Claus Dieter; Ullrich, Joachim; Pfeifer, Thomas; Moshammer, Robert; Eberly, J. H.; Biegert, Jens

    2017-09-01

    Understanding strong-field double ionization of many-electron systems is an important fundamental problem with potential implications for molecular imaging within this regime. Using mid-IR radiation, we unambiguously identify the transition from nonsequential (e , 2 e ) to sequential double ionization in Xe at an intensity below 1014W /c m2 . Ionization from excited orbitals is found to be decisive at low intensities, but we demonstrate that such mechanisms are unimportant in the sequential regime. We utilize these facts to successfully image a molecular dication using laser-induced electron diffraction. This methodology can be used to study molecular dynamics on unprecedented few-femtosecond time scales.

  15. A continuous-time neural model for sequential action.

    Science.gov (United States)

    Kachergis, George; Wyatte, Dean; O'Reilly, Randall C; de Kleijn, Roy; Hommel, Bernhard

    2014-11-05

    Action selection, planning and execution are continuous processes that evolve over time, responding to perceptual feedback as well as evolving top-down constraints. Existing models of routine sequential action (e.g. coffee- or pancake-making) generally fall into one of two classes: hierarchical models that include hand-built task representations, or heterarchical models that must learn to represent hierarchy via temporal context, but thus far lack goal-orientedness. We present a biologically motivated model of the latter class that, because it is situated in the Leabra neural architecture, affords an opportunity to include both unsupervised and goal-directed learning mechanisms. Moreover, we embed this neurocomputational model in the theoretical framework of the theory of event coding (TEC), which posits that actions and perceptions share a common representation with bidirectional associations between the two. Thus, in this view, not only does perception select actions (along with task context), but actions are also used to generate perceptions (i.e. intended effects). We propose a neural model that implements TEC to carry out sequential action control in hierarchically structured tasks such as coffee-making. Unlike traditional feedforward discrete-time neural network models, which use static percepts to generate static outputs, our biological model accepts continuous-time inputs and likewise generates non-stationary outputs, making short-timescale dynamic predictions. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  16. Sequential decisions: a computational comparison of observational and reinforcement accounts.

    Science.gov (United States)

    Mohammadi Sepahvand, Nazanin; Stöttinger, Elisabeth; Danckert, James; Anderson, Britt

    2014-01-01

    Right brain damaged patients show impairments in sequential decision making tasks for which healthy people do not show any difficulty. We hypothesized that this difficulty could be due to the failure of right brain damage patients to develop well-matched models of the world. Our motivation is the idea that to navigate uncertainty, humans use models of the world to direct the decisions they make when interacting with their environment. The better the model is, the better their decisions are. To explore the model building and updating process in humans and the basis for impairment after brain injury, we used a computational model of non-stationary sequence learning. RELPH (Reinforcement and Entropy Learned Pruned Hypothesis space) was able to qualitatively and quantitatively reproduce the results of left and right brain damaged patient groups and healthy controls playing a sequential version of Rock, Paper, Scissors. Our results suggests that, in general, humans employ a sub-optimal reinforcement based learning method rather than an objectively better statistical learning approach, and that differences between right brain damaged and healthy control groups can be explained by different exploration policies, rather than qualitatively different learning mechanisms.

  17. Sequential decisions: a computational comparison of observational and reinforcement accounts.

    Directory of Open Access Journals (Sweden)

    Nazanin Mohammadi Sepahvand

    Full Text Available Right brain damaged patients show impairments in sequential decision making tasks for which healthy people do not show any difficulty. We hypothesized that this difficulty could be due to the failure of right brain damage patients to develop well-matched models of the world. Our motivation is the idea that to navigate uncertainty, humans use models of the world to direct the decisions they make when interacting with their environment. The better the model is, the better their decisions are. To explore the model building and updating process in humans and the basis for impairment after brain injury, we used a computational model of non-stationary sequence learning. RELPH (Reinforcement and Entropy Learned Pruned Hypothesis space was able to qualitatively and quantitatively reproduce the results of left and right brain damaged patient groups and healthy controls playing a sequential version of Rock, Paper, Scissors. Our results suggests that, in general, humans employ a sub-optimal reinforcement based learning method rather than an objectively better statistical learning approach, and that differences between right brain damaged and healthy control groups can be explained by different exploration policies, rather than qualitatively different learning mechanisms.

  18. Implementation of Temperature Sequential Controller on Variable Speed Drive

    Science.gov (United States)

    Cheong, Z. X.; Barsoum, N. N.

    2008-10-01

    There are many pump and motor installations with quite extensive speed variation, such as Sago conveyor, heating, ventilation and air conditioning (HVAC) and water pumping system. A common solution for these applications is to run several fixed speed motors in parallel, with flow control accomplish by turning the motors on and off. This type of control method causes high in-rush current, and adds a risk of damage caused by pressure transients. This paper explains the design and implementation of a temperature speed control system for use in industrial and commercial sectors. Advanced temperature speed control can be achieved by using ABB ACS800 variable speed drive-direct torque sequential control macro, programmable logic controller and temperature transmitter. The principle of direct torque sequential control macro (DTC-SC) is based on the control of torque and flux utilizing the stator flux field orientation over seven preset constant speed. As a result of continuous comparison of ambient temperature to the references temperatures; electromagnetic torque response is particularly fast to the motor state and it is able maintain constant speeds. Experimental tests have been carried out by using ABB ACS800-U1-0003-2, to validate the effectiveness and dynamic respond of ABB ACS800 against temperature variation, loads, and mechanical shocks.

  19. Boric acid irrigation as an adjunct to mechanical periodontal therapy in patients with chronic periodontitis: a randomized clinical trial.

    Science.gov (United States)

    Sağlam, Mehmet; Arslan, Uğur; Buket Bozkurt, Şerife; Hakki, Sema S

    2013-09-01

    The purpose of this single-masked, randomized, controlled clinical trial was to evaluate the effects of boric acid irrigation as an adjunct to scaling and root planing (SRP) on clinical and microbiologic parameters and compare this method with chlorhexidine irrigation and SRP alone in patients with chronic periodontitis (CP). Forty-five systemically healthy patients with CP are included in this study. They were divided into three groups: 1) SRP + saline irrigation (C); 2) SRP + chlorhexidine irrigation (CHX); and 3) SRP + boric acid irrigation (B). To determine an ideal concentration of boric acid, a preclinical analysis was conducted. At baseline, 1 month, and 3 months after treatment, clinical measurements, including plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP), were performed, and subgingival plaque samples were taken. Quantitative analysis of Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), and Treponema denticola (Td) was performed using real-time polymerase chain reaction (PCR) procedures. The concentration of boric acid is 0.75% in this study. All clinical parameters showed statistically significant reduction at all time points compared to baseline in all groups (P 0.05). The PD and CAL reductions for moderately deep pockets (PD ≥5 and 0.05). BOP (percentage) was significantly lower in the B group compared with the CHX and C groups in the first month after treatment (P 0.05). The results of this study suggest that boric acid could be an alternative to chlorhexidine, and it might be more favorable because boric acid was superior in whole-mouth BOP as well as PD and CAL reduction for moderate pockets in early time periods.

  20. Pharmacokinetics of Voriconazole Administered Concomitantly with Fluconazole and Population-Based Simulation for Sequential Use ▿

    OpenAIRE

    Damle, Bharat; Varma, Manthena V.; Wood, Nolan

    2011-01-01

    In clinical practice, antifungal therapy may be switched from fluconazole to voriconazole; such sequential use poses the potential for drug interaction due to cytochrome P450 2C19 (CYP2C19)-mediated inhibition of voriconazole metabolism. This open-label, randomized, two-way crossover study investigated the effect of concomitant fluconazole on voriconazole pharmacokinetics in 10 subjects: 8 extensive metabolizers and 2 poor metabolizers of CYP2C19. The study consisted of 4-day voriconazole-onl...

  1. Time Series Prediction Based on Adaptive Weight Online Sequential Extreme Learning Machine

    Directory of Open Access Journals (Sweden)

    Junjie Lu

    2017-03-01

    Full Text Available A novel adaptive weight online sequential extreme learning machine (AWOS-ELM is proposed for predicting time series problems based on an online sequential extreme learning machine (OS-ELM in this paper. In real-world online applications, the sequentially coming data chunk usually possesses varying confidence coefficients, and the data chunk with a low confidence coefficient tends to mislead the subsequent training process. The proposed AWOS-ELM can improve the training process by accessing the confidence coefficient adaptively and determining the training weight accordingly. Experiments on six time series prediction data sets have verified that the AWOS-ELM algorithm performs better in generalization performance, stability, and prediction ability than the OS-ELM algorithm. In addition, a real-world mechanical system identification problem is considered to test the feasibility and efficacy of the AWOS-ELM algorithm.

  2. A comparison of sequential and spiral scanning techniques in brain CT.

    Science.gov (United States)

    Pace, Ivana; Zarb, Francis

    2015-01-01

    To evaluate and compare image quality and radiation dose of sequential computed tomography (CT) examinations of the brain and spiral CT examinations of the brain imaged on a GE HiSpeed NX/I Dual Slice 2CT scanner. A random sample of 40 patients referred for CT examination of the brain was selected and divided into 2 groups. Half of the patients were scanned using the sequential technique; the other half were scanned using the spiral technique. Radiation dose data—both the computed tomography dose index (CTDI) and the dose length product (DLP)—were recorded on a checklist at the end of each examination. Using the European Guidelines on Quality Criteria for Computed Tomography, 4 radiologists conducted a visual grading analysis and rated the level of visibility of 6 anatomical structures considered necessary to produce images of high quality. The mean CTDI(vol) and DLP values were statistically significantly higher (P vol): 22.06 mGy; DLP: 304.60 mGy • cm) than with the spiral scans (CTDI(vol): 14.94 mGy; DLP: 229.10 mGy • cm). The mean image quality rating scores for all criteria of the sequential scanning technique were statistically significantly higher (P <.05) in the visual grading analysis than those of the spiral scanning technique. In this local study, the sequential technique was preferred over the spiral technique for both overall image quality and differentiation between gray and white matter in brain CT scans. Other similar studies counter this finding. The radiation dose seen with the sequential CT scanning technique was significantly higher than that seen with the spiral CT scanning technique. However, image quality with the sequential technique was statistically significantly superior (P <.05).

  3. Improving the standard sequential treatment of Helicobacter pylori with either extended treatment or by adding bismuth.

    Science.gov (United States)

    Akpinar, Zehra; Akay, Sinan; Unsal, Belkis

    2017-06-01

    Standard sequential treatment for Helicobacter pylori (H. pylori) eradication has less success because of increasing clarithromycin resistance. Extended treatment and bismuth containing regimens were, therefore, investigated. Consecutive H. pylori-positive patients with dyspepsia were randomly allocated to one of the three sequential regimens: The first group was given lansoprazole 30mg b.i.d. plus amoxicillin 1g b.i.d. for the first 5days, followed by lansoprazole 30mg b.i.d., clarithromycin 500mg b.i.d., and metronidazole 500mg t.i.d. for the second 5days (standard sequential, SS). The second group was given the same regimen but for 7+7days instead of 5+5days (extended sequential, ES). In the third group, colloidal bismuth 600mg b.i.d. was added to the second regimen for 14days (extended sequential+bismuth subcitrate, ES+B). Urea breath test or histology was performed before enrolment and 6weeks after the end of treatment to detect H. pylori. A total of 280 patients were included in the study. Per-protocol eradication rates were 62% (56/90), 72% (56/78), and 75% (54/72) in patients who received SS, ES, and ES+B regimens, respectively. Moreover, intention-to-treat eradication rates were 53% (56/104), 62% (56/90) and 62% (54/86), respectively. The differences in eradication rates between the groups were not statistically significant. Although prolonging of the sequential treatment to 14days may be considered, addition of bismuth to the regimen is of no avail. Copyright © 2017 Pan-Arab Association of Gastroenterology. Published by Elsevier B.V. All rights reserved.

  4. A comparative study of the effect of the intrusion arch and straight wire mechanics on incisor root resorption: A randomized, controlled trial.

    Science.gov (United States)

    de Almeida, Marcio Rodrigues; Marçal, Aline Siqueira Butzke; Fernandes, Thais Maria Freire; Vasconcelos, Juliana Brito; de Almeida, Renato Rodrigues; Nanda, Ravindra

    2017-10-06

    To analyze and compare external apical root resorption (EARR) of maxillary incisors treated by intrusion arch or continuous archwire mechanics. This cone-beam computed tomography (CBCT) study analyzed 28 deep bite patients in the permanent dentition who were randomly divided into two groups: Group 1, 12 patients with initial mean age of 15.1 ± 1.6 years and mean overbite of 4.6 ± 1.2 mm treated with the Connecticut intrusion arch (CIA) in the upper arch (Ortho Organizers, Carlsbad, Calif) for a mean period of 5.8 ± 1.27 months. Group 2, 16 patients with initial mean age of 22.1 ± 5.7 years and mean overbite of 4.1 ± 1.1 mm treated with conventional leveling and alignment using continuous archwire mechanics for 6.1 ± 0.81 months. The degree of EARR was detected in 112 maxillary incisors by using CBCT scans and a three-dimensional program (Dolphin 11.7, Dolphin Imaging & Management Solutions, Chatsworth, Calif). The CBCT scans were obtained before (T1) and 6 months after initiation of treatment (T2). Differences between and within groups were assessed by nonpaired and paired t-tests, respectively, with a 5% significance level. Significant differences were found for both groups between T1 and T2 (P intrusion arch did not lead to greater EARR of maxillary incisors when compared with conventional orthodontic mechanics.

  5. Comparing interventions and exploring neural mechanisms of exercise in Parkinson disease: a study protocol for a randomized controlled trial.

    Science.gov (United States)

    Earhart, Gammon M; Duncan, Ryan P; Huang, John L; Perlmutter, Joel S; Pickett, Kristen A

    2015-02-05

    Effective treatment of locomotor dysfunction in Parkinson disease (PD) is essential, as gait difficulty is an early and major contributor to disability. Exercise is recommended as an adjunct to traditional treatments for improving gait, balance, and quality of life. Among the exercise approaches known to improve walking, tango and treadmill training have recently emerged as two promising therapies for improving gait, disease severity and quality of life, yet these two interventions have not been directly compared to each other. Prior studies have been helpful in identifying interventions effective in improving gait function, but have done little to elucidate the neural mechanisms underlying functional improvements. The primary objective of the proposed work is to compare the effects of three community-based exercise programs, tango, treadmill training and stretching, on locomotor function in individuals with PD. In addition, we aim to determine whether and how these interventions alter functional connectivity of locomotor control networks in the brain. One hundred and twenty right-handed individuals with idiopathic PD who are at least 30 years of age will be assigned in successive waves to one of three community-based exercise groups: tango dancing, treadmill training or stretching (control). Each group will receive three months of exercise training with twice weekly one-hour group classes. Each participant will be evaluated at three time points: pre-intervention (baseline), post-intervention (3 months), and follow-up (6 months). All evaluations will include assessment of gait, balance, disease severity, and quality of life. Baseline and post-intervention evaluations will also include task-based functional magnetic resonance imaging (fMRI) and resting state functional connectivity MRI. All MRI and behavioral measures will be conducted with participants OFF anti-Parkinson medication, with behavioral measures also assessed ON medication. This study will provide

  6. Dry needling in a manual physiotherapy and therapeutic exercise protocol for patients with chronic mechanical shoulder pain of unspecific origin: a protocol for a randomized control trial.

    Science.gov (United States)

    Tejera-Falcón, Emma; Toledo-Martel, Nuria Del Carmen; Sosa-Medina, Francisco Manuel; Santana-González, Fátima; Quintana-de la Fe, Miriam Del Pino; Gallego-Izquierdo, Tomás; Pecos-Martín, Daniel

    2017-09-18

    Shoulder pain of musculoskeletal origin is the main cause of upper limb pain of non-traumatic origin. Despite being one of the most common reasons for consultation, there is no established protocol for treatment due to the complexity of its etiology. However, it has been shown that the presence of myofascial trigger points on the shoulder muscles is a common condition associated with patients suffering from shoulder pain. This protocol has been created which describes the design of a randomized controlled trial to evaluate the effectiveness of the inclusion of dry needling (DN) within a protocol of manual physiotherapy and therapeutic exercise in the treatment of chronic shoulder pain of unspecific origin. Thirty-six participants aged 18-65 years will be recruited having mechanical chronic shoulder pain on unspecific origin and meeting the inclusion criteria. These will be randomized to one of two interventions, (i) DN, manual physiotherapy and therapeutic exercise or (ii) sham DN, manual physiotherapy and therapeutic exercise. The protocol will cover 6 weeks of treatment, with a 6-month follow-up. Our main outcome measure will be the Visual Analogue Scale for pain. This is the first study to combine the use of DN, manual physiotherapy and an exercise program with a 6-month follow-up, thus becoming a new contribution to the treatment of chronic shoulder pain, while new lines of research may be established to help determine the effects of DN on chronic shoulder pain and the frequency and proper dosage. International Standard Randomized Controlled Trial Number Register: ISRCTN30604244 ( http://www.controlled-trials.com ) 29 June 2016.

  7. Efficacy of kinesiology tape versus postural correction exercises on neck disability and axioscapular muscles fatigue in mechanical neck dysfunction: A randomized blinded clinical trial.

    Science.gov (United States)

    El-Abd, Aliaa M; Ibrahim, Abeer R; El-Hafez, Haytham M

    2017-04-01

    Mechanical neck dysfunction (MND), with axioscapular muscles fatigue, is highly prevalent worldwide. While postural correction is commonly used for its treatment, efficacy of kinesiology tape (KT) has received considerable attention. To determine the effectiveness of KT versus correction exercises on neck disability, and axioscapular muscles fatigue in MND patients. 46 MND patients were randomly assigned into 1 of 2 groups receiving 4 weeks treatment of either KT or correction exercises. Neck disability and axioscapular muscles fatigue as median frequency of electromyography (EMG-MF) were measured pre and post treatment. Group-by-time interaction was not significant in the multivariable test. Post hoc tests revealed that KT produced more disability reduction than the postural exercises. However, there was no significant interaction for EMG-MF. KT has been found to be more effective than postural exercises to reduce neck disability. However, both modalities have similar effects to reduce axioscapular muscles fatigue. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Effect of charge quantity on conduction mechanism of high- and low-resistance states during forming process in a one-transistor-one-resistor resistance random access memory

    Science.gov (United States)

    Wu, Cheng-Hsien; Chang, Ting-Chang; Tsai, Tsung-Ming; Chang, Kuan-Chang; Chu, Tian-Jian; Pan, Chih-Hung; Su, Yu-Ting; Chen, Po-Hsun; Lin, Shih-Kai; Hu, Shih-Jie; Sze, Simon M.

    2017-05-01

    The forming process is a necessary and irreversible process to activate the resistance switching behavior in a resistance random access memory (RRAM) device. However, during the forming process, an overshoot current leads to device damage and causes inferior resistance switching characteristics; consequently, the process is considered to be a key factor in device degradation. In this paper, we find that a discontinuous conduction path can be formed by a pulse forming process such that the operation current can be reduced. We further investigate how the charge quantity during the forming process affects the carrier conduction mechanism of HRS, with all experiments and results demonstrated on one-transistor-one-resistor (1T1R) devices.

  9. Oxygen self-diffusion mechanisms in monoclinic Zr O2 revealed and quantified by density functional theory, random walk analysis, and kinetic Monte Carlo calculations

    Science.gov (United States)

    Yang, Jing; Youssef, Mostafa; Yildiz, Bilge

    2018-01-01

    In this work, we quantify oxygen self-diffusion in monoclinic-phase zirconium oxide as a function of temperature and oxygen partial pressure. A migration barrier of each type of oxygen defect was obtained by first-principles calculations. Random walk theory was used to quantify the diffusivities of oxygen interstitials by using the calculated migration barriers. Kinetic Monte Carlo simulations were used to calculate diffusivities of oxygen vacancies by distinguishing the threefold- and fourfold-coordinated lattice oxygen. By combining the equilibrium defect concentrations obtained in our previous work together with the herein calculated diffusivity of each defect species, we present the resulting oxygen self-diffusion coefficients and the corresponding atomistically resolved transport mechanisms. The predicted effective migration barriers and diffusion prefactors are in reasonable agreement with the experimentally reported values. This work provides insights into oxygen diffusion engineering in Zr O2 -related devices and parametrization for continuum transport modeling.

  10. Glatiramer Acetate in Treatment of Multiple Sclerosis: A Toolbox of Random Co-Polymers for Targeting Inflammatory Mechanisms of both the Innate and Adaptive Immune System?

    Directory of Open Access Journals (Sweden)

    Thomas Vorup-Jensen

    2012-11-01

    Full Text Available Multiple sclerosis is a disease of the central nervous system, resulting in the demyelination of neurons, causing mild to severe symptoms. Several anti-inflammatory treatments now play a significant role in ameliorating the disease. Glatiramer acetate (GA is a formulation of random polypeptide copolymers for the treatment of relapsing-remitting MS by limiting the frequency of attacks. While evidence suggests the influence of GA on inflammatory responses, the targeted molecular mechanisms remain poorly understood. Here, we review the multiple pharmacological modes-of-actions of glatiramer acetate in treatment of multiple sclerosis. We discuss in particular a newly discovered interaction between the leukocyte-expressed integrin αMβ2 (also called Mac-1, complement receptor 3, or CD11b/CD18 and perspectives on the GA co-polymers as an influence on the function of the innate immune system.

  11. The mechanical effect of kinesiology tape on rounded shoulder posture in seated male workers: a single-blinded randomized controlled pilot study.

    Science.gov (United States)

    Han, Jin-Tae; Lee, Jung-Hoon; Yoon, Chul-Han

    2015-02-01

    Single-blinded randomized controlled pilot study. To examine the changes in pectoralis minor length (PML), the supine measurement of rounded shoulder posture (RSP), and the total scapular distance (TSD) in seated male workers with RSP, after rounded-shoulder-taping (RST) using kinesiology tape with (experimental taping) and without stretch (placebo taping). RSP, a postural impairment, is a known cause of upper quarter pain. Fourteen men with RSP, who worked for at least 7 h/d in a seated position, were selected for RST, with the shoulders randomly assigned to two kinesiology taping methods: (1) with 35-40% stretch of its original length; and (2) without stretch. The PML, supine measurements of RSP, and TSD, before and after kinesiology taping, with and without stretch, were assessed. Kinesiology taping with stretch significantly increased the PML and significantly decreased the supine measurement of RSP and TSD; kinesiology taping without stretch did not increase the PML significantly and did not decrease the supine measurement of RSP and TSD. RST using kinesiology tape with stretch produces immediate mechanical correction of RSP in seated male workers.

  12. Evaluation of the effect on patient parameters of not monitoring gastric residual volume in intensive care patients on a mechanical ventilator receiving enteral feeding: A randomized clinical trial.

    Science.gov (United States)

    Ozen, Nurten; Tosun, Nuran; Yamanel, Levent; Altintas, Neriman Defne; Kilciler, Guldem; Ozen, Volkan

    2016-06-01

    This study aimed to evaluate the effects of not measuring gastric residual volume (GRV) in intensive care patients on a mechanical ventilator and receiving enteral feeding on the feeding intolerance, gastroesophageal reflux (GER) risk, and nutritional adequacy. This randomized clinical study was performed in 2 medical intensive care units of 2 university hospitals in Ankara, Turkey. The patients were randomized into 2 groups. In the group with GRV monitoring, GRV was measured 3 times a day, and the GRV threshold was accepted as 250 mL. In addition, 24-hour pH monitoring was used in this group to assess the risk of GER. In the group without GRV monitoring, GRV was not measured. The patients were followed-up for 5 days. The feeding targets were reached more quickly in the group without GRV monitoring (n = 26) with no increase in the complication rate (P monitoring (n = 25) (P > .05). The discrepancies in GRV measurement make it unreliable for monitoring feeding intolerance and GER. The use of GRV measurements may therefore be discontinued as part of the standard care protocol in medical intensive care units. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. The sequential contractions of the rumen associated with eructation in sheep

    Science.gov (United States)

    Ruckebusch, Y.; Tomov, T.

    1973-01-01

    1. The orderly sequential movements of the reticulum and the rumen were studied in conscious sheep by electromyography using enamelled stainless-steel wires implanted in various regions of the stomach wall and by recording mechanical changes within the various parts of the organ. Electrical activity of the rumen and/or pressure changes were related to eructation when the animals were at rest, feeding or ruminating. 2. Secondary contractions of the rumen were found to originate in the ventral blind sac immediately following a primary contraction or independently. The wave of contraction originating in the ventral blind sac was seen to pass in a circular manner to the dorsal blind sac, the dorsal sac, the ventral sac and finally once more to the ventral blind sac. Eructation occurs at the end of the contraction of the dorsal sac. In each case, the time required to initiate the secondary cycle depended on the strength of contraction of the ventral blind sac. 3. Sustained gaseous distension elicited numerous secondary contractions of the rumen concurrent with a lower frequency of reticular contractions. Although some secondary contractions were incomplete, all began with contraction of the ventral blind sac and were associated with eructation. 4. Chemical stimulation of the rumen by fatty acids at pH 5·5-5·9 increased the ratio of secondary to primary contractions of the rumen to a varying extent depending on their initial rate. 5. It was concluded that the seemingly random occurrence of a secondary cycle of the rumen was dependent on the activity of the ventral blind sac and its pattern could be altered by both mechanical and chemical stimulation. PMID:4763997

  14. Decreasing Delirium through Music (DDM) in critically ill, mechanically ventilated patients in the intensive care unit: study protocol for a pilot randomized controlled trial.

    Science.gov (United States)

    Khan, Sikandar H; Wang, Sophia; Harrawood, Amanda; Martinez, Stephanie; Heiderscheit, Annie; Chlan, Linda; Perkins, Anthony J; Tu, Wanzhu; Boustani, Malaz; Khan, Babar

    2017-11-29

    Delirium is a highly prevalent and morbid syndrome in intensive care units (ICUs). Changing the stressful environment within the ICU via music may be an effective and a scalable way to reduce the burden of delirium. The Decreasing Delirium through Music (DDM) study is a three-arm, single-blind, randomized controlled feasibility trial. Sixty patients admitted to the ICU with respiratory failure requiring mechanical ventilation will be randomized to one of three arms (20 participants per arm): (1) personalized music, (2) non-personalized relaxing music, or (3) attention-control. Music preferences will be obtained from all enrolled participants or their family caregivers. Participants will receive two 1-h audio sessions a day through noise-cancelling headphones and mp3 players. Our primary aim is to determine the feasibility of the trial design (recruitment, adherence, participant retention, design and delivery of the music intervention). Our secondary aim is to estimate the potential effect size of patient-preferred music listening in reducing delirium, as measured by the Confusion Assessment Method for the ICU (CAM-ICU). Participants will receive twice daily assessments for level of sedation and presence of delirium. Enrolled participants will be followed in the hospital until death, discharge, or up to 28 days, and seen in the Critical Care Recovery Clinic at 90 days. DDM is a feasibility trial to provide personalized and non-personalized music interventions for critically ill, mechanically ventilated patients. Our trial will also estimate the preliminary efficacy of music interventions on reducing delirium incidence and severity. ClinicalTrials.gov, Identifier: NCT03095443 . Registered on 23 March 2017.

  15. Electroacupuncture prevents endothelial dysfunction induced by ischemia-reperfusion injury via a cyclooxygenase-2-dependent mechanism: A randomized controlled crossover trial.

    Directory of Open Access Journals (Sweden)

    Seung Min Kathy Lee

    Full Text Available Exploring clinically effective methods to reduce ischemia-reperfusion (IR injury in humans is critical. Several drugs have shown protective effects, but studies using other interventions have been rare. Electroacupuncture (EA has induced similar protection in several animal studies but no study has investigated how the effects could be translated and reproduced in humans. This study aimed to explore the potential effect and mechanisms of EA in IR-induced endothelial dysfunction in humans.This is a prospective, randomized, crossover, sham-controlled trial consisting of two protocols. Protocol 1 was a crossover study to investigate the effect of EA on IR-induced endothelial dysfunction. Twenty healthy volunteers were randomly assigned to EA or sham EA (sham. Flow mediated dilation (FMD of the brachial artery (BA, nitroglycerin-mediated endothelial independent dilation, blood pressure before and after IR were measured. In protocol 2, seven volunteers were administered COX-2 inhibitor celecoxib (200 mg orally twice daily for five days. After consumption, volunteers underwent FMD before and after IR identical to protocol 1.In protocol 1, baseline BA diameter, Pre-IR BA diameter and FMD were similar between the two groups (p = NS. After IR, sham group showed significantly blunted FMD (Pre-IR: 11.41 ± 3.10%, Post-IR: 4.49 ± 2.04%, p < 0.001. However, EA protected this blunted FMD (Pre-IR: 10.96 ± 5.30%, Post-IR: 9.47 ± 5.23%, p = NS, p < 0.05 compared with sham EA after IR. In protocol 2, this protective effect was completely abolished by pre-treatment with celecoxib (Pre-IR: 11.05 ± 3.27%; Post-IR: 4.20 ± 1.68%, p = 0.001.EA may prevent IR-induced endothelial dysfunction via a COX-2 dependent mechanism.

  16. Effect of Mechanical Ventilation Mode Type on Intra- and Postoperative Blood Loss in Patients Undergoing Posterior Lumbar Interbody Fusion Surgery: A Randomized Controlled Trial.

    Science.gov (United States)

    Kang, Woon-Seok; Oh, Chung-Sik; Kwon, Won-Kyoung; Rhee, Ka Young; Lee, Yun Gu; Kim, Tae-Hoon; Lee, Suk Ha; Kim, Seong-Hyop

    2016-07-01

    The aim of study was to evaluate the effect of mechanical ventilation mode type, pressure-controlled ventilation (PCV), or volume-controlled ventilation (VCV) on intra- and postoperative surgical bleeding in patients undergoing posterior lumbar interbody fusion (PLIF) surgery. This was a prospective, randomized, single-blinded, and parallel study that included 56 patients undergoing PLIF and who were mechanically ventilated using PCV or VCV. A permuted block randomization was used with a computer-generated list. The hemodynamic and respiratory parameters were measured after anesthesia induction in supine position, 5 min after patients were changed from supine to prone position, at the time of skin closure, and 5 min after the patients were changed from prone to supine position. The amount of intraoperative surgical bleeding, fluid administration, urine output, and transfusion requirement were measured at the end of surgery. The amount of postoperative bleeding and transfusion requirement were recorded every 24 h for 72 h. The primary outcome was the amount of intraoperative surgical bleeding, and 56 patients were analyzed. The amount of intraoperative surgical bleeding was significantly less in the PCV group than that in the VCV group (median, 253.0 [interquartile range, 179.0 to 316.5] ml in PCV group vs. 382.5 [328.0 to 489.5] ml in VCV group; P < 0.001). Comparing other parameters between groups, only peak inspiratory pressure at each measurement point in PCV group was significantly lower than that in VCV group. No harmful events were recorded. Intraoperative PCV decreased intraoperative surgical bleeding in patients undergoing PLIF, which may be related to lower intraoperative peak inspiratory pressure.

  17. Low tidal volume mechanical ventilation against no ventilation during cardiopulmonary bypass heart surgery (MECANO): study protocol for a randomized controlled trial.

    Science.gov (United States)

    Nguyen, Lee S; Merzoug, Messaouda; Estagnasie, Philippe; Brusset, Alain; Law Koune, Jean-Dominique; Aubert, Stephane; Waldmann, Thierry; Grinda, Jean-Michel; Gibert, Hadrien; Squara, Pierre

    2017-12-02

    Postoperative pulmonary complications are a leading cause of morbidity and mortality after cardiac surgery. There are no recommendations on mechanical ventilation associated with cardiopulmonary bypass (CPB) during surgery and anesthesiologists perform either no ventilation (noV) at all during CPB or maintain low tidal volume (LTV) ventilation. Indirect evidence points towards better pulmonary outcomes when LTV is performed but no large-scale prospective trial has yet been published in cardiac surgery. The MECANO trial is a single-center, double-blind, randomized, controlled trial comparing two mechanical ventilation strategies, noV and LTV, during cardiac surgery with CPB. In total, 1500 patients are expected to be included, without any restrictions. They will be randomized between noV and LTV on a 1:1 ratio. The noV group will receive no ventilation during CPB. The LTV group will receive 5 breaths/minute with a tidal volume of 3 mL/kg and positive end-expiratory pressure of 5 cmH2O. The primary endpoint will be a composite of all-cause mortality, early respiratory failure defined as a ratio of partial pressure of oxygen/fraction of inspired oxygen ventilation, mechanical ventilation or high-flow oxygen) at 2 days after arrival in the ICU or ventilator-acquired pneumonia defined by the Center of Disease Control. Lung recruitment maneuvers will be performed in the noV and LTV groups at the end of surgery and at arrival in ICU with an insufflation at +30 cmH20 for 5 seconds. Secondary endpoints are those composing the primary endpoint with the addition of pneumothorax, CPB duration, quantity of postoperative bleeding, red blood cell transfusions, revision surgery requirements, length of stay in the ICU and in the hospital and total hospitalization costs. Patients will be followed until hospital discharge. The MECANO trial is the first of its kind to compare in a double-blind design, a no-ventilation to a low-tidal volume strategy for mechanical ventilation during

  18. Increased efficacy of photodynamic therapy via sequential targeting

    Science.gov (United States)

    Kessel, David; Aggarwal, Neha; Sloane, Bonnie F.

    2014-03-01

    Photokilling depends on the generation of death signals after photosensitized cells are irradiated. A variety of intracellular organelles can be targeted for photodamage, often with a high degree of specificity. We have discovered that a low level of photodamage directed against lysosomes can sensitize both a murine hepatoma cell line (in 2D culture) and an inflammatory breast cancer line of human origin (in a 3D model) to subsequent photodamage directed at mitochondria. Additional studies were carried out with hepatoma cells to explore possible mechanisms. The phototoxic effect of the `sequential targeting' approach was associated with an increased apoptotic response. The low level of lysosomal photodamage did not lead to any detectable migration of Fe++ from lysosomes to mitochondria or increased reactive oxygen species (ROS) formation after subsequent mitochondrial photodamage. Instead, there appears to be a signal generated that can amplify the pro-apoptotic effect of subsequent mitochondrial photodamage.

  19. Wavelet Network: Online Sequential Extreme Learning Machine for Nonlinear Dynamic Systems Identification

    Directory of Open Access Journals (Sweden)

    Dhiadeen Mohammed Salih

    2015-01-01

    Full Text Available A single hidden layer feedforward neural network (SLFN with online sequential extreme learning machine (OSELM algorithm has been introduced and applied in many regression problems successfully. However, using SLFN with OSELM as black-box for nonlinear system identification may lead to building models for the identified plant with inconsistency responses from control perspective. The reason can refer to the random initialization procedure of the SLFN hidden node parameters with OSELM algorithm. In this paper, a single hidden layer feedforward wavelet network (WN is introduced with OSELM for nonlinear system identification aimed at getting better generalization performances by reducing the effect of a random initialization procedure.

  20. Effectiveness of sequential v. standard triple therapy for treatment of Helicobacter pylori infection in children in Nairobi, Kenya.

    Science.gov (United States)

    Laving, Ahmed; Kamenwa, Rose; Sayed, Shahin; Kimang'a, Andrew Nyerere; Revathi, Gunturu

    2013-10-23

    Once the diagnosis of Helicobacter pylori is confirmed, treatment requires at least two antibiotics and an acid inhibitor for a minimum of seven days. Unfortunately, treatment failures are being frequently reported. Treatment regimens that include sequential administration of antibiotics with acid inhibitors have been developed to try and increase the rate of eradication. To determine the effectiveness of a novel 10-day sequential therapy compared with the standard 10-day triple therapy for treatment of H. pylori infection in children. A double-blinded, randomised, controlled trial was conducted. Children under the age of 16 years with recurrent abdominal pain associated with dyspepsia and diagnosed with H. pylori by histology were randomly allocated either to a 10-day sequential treatment regimen or to a 10-day conventional triple therapy. Analysis of the outcome of this study was based on clinical improvement and confirmed H. pylori eradication based on stool H. pylori antigen detection and/or repeat endoscopy. Of the 71 patients included in the analysis, 45 (63.4%) were given the 10-day conventional treatment while 26 (36.6%) received the 10-day sequential treatment. There was no difference in clinical improvement after treatment in the two therapies. However, there was a significant difference in the eradication of H. pylori between the conventional v. sequential regimens (48.8% v. 84.6%, respectively; p=0.02, odds ratio 0.19). The sequential treatment had a significantly higher H. pylori eradication rate than the conventional treatment.

  1. Tailored sequential drug release from bilayered calcium sulfate composites

    Energy Technology Data Exchange (ETDEWEB)

    Orellana, Bryan R.; Puleo, David A., E-mail: puleo@uky.edu

    2014-10-01

    The current standard for treating infected bony defects, such as those caused by periodontal disease, requires multiple time-consuming steps and often multiple procedures to fight the infection and recover lost tissue. Releasing an antibiotic followed by an osteogenic agent from a synthetic bone graft substitute could allow for a streamlined treatment, reducing the need for multiple surgeries and thereby shortening recovery time. Tailorable bilayered calcium sulfate (CS) bone graft substitutes were developed with the ability to sequentially release multiple therapeutic agents. Bilayered composite samples having a shell and core geometry were fabricated with varying amounts (1 or 10 wt.%) of metronidazole-loaded poly(lactic-co-glycolic acid) (PLGA) particles embedded in the shell and simvastatin directly loaded into either the shell, core, or both. Microcomputed tomography showed the overall layered geometry as well as the uniform distribution of PLGA within the shells. Dissolution studies demonstrated that the amount of PLGA particles (i.e., 1 vs. 10 wt.%) had a small but significant effect on the erosion rate (3% vs. 3.4%/d). Mechanical testing determined that introducing a layered geometry had a significant effect on the compressive strength, with an average reduction of 35%, but properties were comparable to those of mandibular trabecular bone. Sustained release of simvastatin directly loaded into CS demonstrated that changing the shell to core volume ratio dictates the duration of drug release from each layer. When loaded together in the shell or in separate layers, sequential release of metronidazole and simvastatin was achieved. By introducing a tunable, layered geometry capable of releasing multiple drugs, CS-based bone graft substitutes could be tailored in order to help streamline the multiple steps needed to regenerate tissue in infected defects. - Highlights: • Bilayered CS composites were fabricated as potential bone graft substitutes. • The shell

  2. Sequential tool use in great apes.

    Science.gov (United States)

    Martin-Ordas, Gema; Schumacher, Lena; Call, Josep

    2012-01-01

    Sequential tool use is defined as using a tool to obtain another non-food object which subsequently itself will serve as a tool to act upon a further (sub)goal. Previous studies have shown that birds and great apes succeed in such tasks. However, the inclusion of a training phase for each of the sequential steps and the low cost associated with retrieving the longest tools limits the scope of the conclusions. The goal of the experiments presented here was, first to replicate a previous study on sequential tool use conducted on New Caledonian crows and, second, extend this work by increasing the cost of retrieving a tool in order to test tool selectivity of apes. In Experiment 1, we presented chimpanzees, orangutans and bonobos with an out-of-reach reward, two tools that were available but too short to reach the food and four out-of-reach tools differing in functionality. Similar to crows, apes spontaneously used up to 3 tools in sequence to get the reward and also showed a strong preference for the longest out-of reach tool independently of the distance of the food. In Experiment 2, we increased the cost of reaching for the longest out-of reach tool. Now apes used up to 5 tools in sequence to get the reward and became more selective in their choice of the longest tool as the costs of its retrieval increased. The findings of the studies presented here contribute to the growing body of comparative research on tool use.

  3. Sequential tool use in great apes.

    Directory of Open Access Journals (Sweden)

    Gema Martin-Ordas

    Full Text Available Sequential tool use is defined as using a tool to obtain another non-food object which subsequently itself will serve as a tool to act upon a further (subgoal. Previous studies have shown that birds and great apes succeed in such tasks. However, the inclusion of a training phase for each of the sequential steps and the low cost associated with retrieving the longest tools limits the scope of the conclusions. The goal of the experiments presented here was, first to replicate a previous study on sequential tool use conducted on New Caledonian crows and, second, extend this work by increasing the cost of retrieving a tool in order to test tool selectivity of apes. In Experiment 1, we presented chimpanzees, orangutans and bonobos with an out-of-reach reward, two tools that were available but too short to reach the food and four out-of-reach tools differing in functionality. Similar to crows, apes spontaneously used up to 3 tools in sequence to get the reward and also showed a strong preference for the longest out-of reach tool independently of the distance of the food. In Experiment 2, we increased the cost of reaching for the longest out-of reach tool. Now apes used up to 5 tools in sequence to get the reward and became more selective in their choice of the longest tool as the costs of its retrieval increased. The findings of the studies presented here contribute to the growing body of comparative research on tool use.

  4. Decoding restricted participation in sequential electricity markets

    Energy Technology Data Exchange (ETDEWEB)

    Knaut, Andreas; Paschmann, Martin

    2017-06-15

    Restricted participation in sequential markets may cause high price volatility and welfare losses. In this paper we therefore analyze the drivers of restricted participation in the German intraday auction which is a short-term electricity market with quarter-hourly products. Applying a fundamental electricity market model with 15-minute temporal resolution, we identify the lack of sub-hourly market coupling being the most relevant driver of restricted participation. We derive a proxy for price volatility and find that full market coupling may trigger quarter-hourly price volatility to decrease by a factor close to four.

  5. Sequential neural models with stochastic layers

    DEFF Research Database (Denmark)

    Fraccaro, Marco; Sønderby, Søren Kaae; Paquet, Ulrich

    2016-01-01

    How can we efficiently propagate uncertainty in a latent state representation with recurrent neural networks? This paper introduces stochastic recurrent neural networks which glue a deterministic recurrent neural network and a state space model together to form a stochastic and sequential neural ...... the uncertainty in a latent path, like a state space model, we improve the state of the art results on the Blizzard and TIMIT speech modeling data sets by a large margin, while achieving comparable performances to competing methods on polyphonic music modeling....

  6. THE DEVELOPMENT OF SPECIAL SEQUENTIALLY-TIMED

    Directory of Open Access Journals (Sweden)

    Stanislav LICHOROBIEC

    2016-06-01

    Full Text Available This article documents the development of the noninvasive use of explosives during the destruction of ice mass in river flows. The system of special sequentially-timed charges utilizes the increase in efficiency of cutting charges by covering them with bags filled with water, while simultaneously increasing the effect of the entire system of timed charges. Timing, spatial combinations during placement, and the linking of these charges results in the loosening of ice barriers on a frozen waterway, while at the same time regulating the size of the ice fragments. The developed charges will increase the operability and safety of IRS units.

  7. Instantaneous responses to high-frequency chest wall oscillation in patients with acute pneumonic respiratory failure receiving mechanical ventilation: A randomized controlled study.

    Science.gov (United States)

    Chuang, Ming-Lung; Chou, Yi-Ling; Lee, Chai-Yuan; Huang, Shih-Feng

    2017-03-01

    Endotracheal intubation and prolonged immobilization of patients receiving mechanical ventilation may reduce expectoration function. High-frequency chest wall oscillation (HFCWO) may ameliorate airway secretion movement; however, the instantaneous changes in patients' cardiopulmonary responses are unknown. Moreover, HFCWO may influence ventilator settings by the vigorous oscillation. The aim of this study was to investigate these issues. Seventy-three patients (52 men) aged 71.5 ± 13.4 years who were intubated with mechanical ventilation for pneumonic respiratory failure were recruited and randomly classified into 2 groups (HFCWO group, n = 36; and control group who received conventional chest physical therapy (CCPT, n = 37). HFCWO was applied with a fixed protocol, whereas CCPT was conducted using standard protocols. Both groups received sputum suction after the procedure. Changes in ventilator settings and the subjects' responses were measured at preset intervals and compared within groups and between groups. Oscillation did not affect the ventilator settings (all P > 0.05). The mean airway pressure, breathing frequency, and rapid shallow breathing index increased, and the tidal volume and SpO2 decreased (all P ventilation decreased (all P ventilator settings, whereas CCPT maintains a steadier condition. After sputum suction, HFCWO slightly improved Ppeak compared to CCPT, suggesting that the study extends the indications of HFCWO for these patients in intensive care unit. (ClinicalTrials.gov number NCT02758106, retrospectively registered.).

  8. Narrative exposure therapy for immigrant children traumatized by war: study protocol for a randomized controlled trial of effectiveness and mechanisms of change.

    Science.gov (United States)

    Kangaslampi, Samuli; Garoff, Ferdinand; Peltonen, Kirsi

    2015-06-17

    Millions of children worldwide suffer from posttraumatic stress disorder (PTSD) symptoms and other mental health problems due to repeated exposure to war or organized violence. Forms of cognitive-behavioral therapy (CBT) are the most commonly used treatment for PTSD and appear to be effective for children as well, but little is known about the mechanisms of change through which they achieve their effectiveness. Here we present the study protocol of a randomized controlled trial (RCT) studying the effectiveness and mechanisms of change of Narrative Exposure Therapy (NET), a CBT-based, manualized, short-term intervention for PTSD symptoms resulting from repeated traumatization, in immigrant children traumatized by war. We are conducting a multicentre, pragmatic RCT in a usual care setting. Up to 80 9-17-year-old immigrant children who have experienced war and suffer from PTSD symptoms will be randomized into intervention (NET) and control (treatment as usual, TAU) groups of equal sizes. The effectiveness of NET treatment will be compared to both a waiting list and the parallel TAU positive control group, on the primary outcomes of PTSD and depressive symptoms, psychological distress, resilience, and level of cognitive performance. The effects of the intervention on traumatic memories and posttraumatic cognitions will be studied as potential mechanisms of change mediating overall treatment effectiveness. The possible moderating effects of peritraumatic dissociation, level of cognitive performance, and gender on treatment effectiveness will also be considered. We hypothesize that NET will be more effective than a waitlist condition or TAU in reducing PTSD and other symptoms and improving resilience, and that these effects will be mediated by changes in traumatic memories and posttraumatic cognitions. The results of this trial will provide evidence for the effectiveness of NET in treating trauma-related symptoms in immigrant children affected by war. The trial will also

  9. The quantity-effect relationship and physiological mechanisms of different acupuncture manipulations on posterior circulation ischemia with vertigo: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Deng, Shi-Zhe; Zhao, Xiao-Feng; Huang, Ling-Hui; He, Si; Wen, Yan; Zhang, Chao; Tian, Guang; Wang, Tian; Wu, Fen-Fen; Meng, Zhi-Hong; Shi, Xue-Min

    2015-04-11

    Recent experiments have demonstrated that different needling manipulations may induce variable effects via diverse physiological mechanisms. A previous study indicated that needling at Fengchi (GB 20) improved cerebral blood flow in patients with vertigo induced by posterior circulation ischemia (PCI). In this study, we aim to explore the quantity-effect relationship and the physiological mechanisms underlying different acupuncture manipulations in PCI patients with vertigo. We propose a pragmatic randomized and controlled trial. All participants, outcome assessors, and statisticians will be blinded. A total of 144 eligible participants will be randomized into one of four treatment groups receiving acupuncture at Fengchi (GB 20) with different one-minute manipulation parameters. Group 1 will receive twirling at a frequency of 60 times per minute toward the contralateral outer canthus at a depth of 0.5 to 0.8 cun. Group 2 will receive twirling at a frequency of 60 times per minute toward the Adam's apple at a depth of 0.5 to 0.8 cun. Group 3 will receive twirling at a frequency of 120 times per minute toward the contralateral outer canthus at a depth of 0.5 to 0.8 cun. Group 4 will receive twirling at a frequency of120 times per minute toward the Adam's apple at a depth of 0.5 to 0.8 cun. Additional points will be added based on individualized pattern diagnoses. The participants will receive 14 acupuncture sessions over 3 to 4 weeks. The subjects will be assessed at two time points: baseline and post-treatment. The primary outcome measurements will include subjective measurements (Vertebrobasilar System Ischemic Neurological Impairment Scale, UCLA Dizziness Questionnaire, Activities of Daily Living Scale, and Psychological and Social Adaptation Scale) and objective measurements (Transcranial Doppler, carotid ultrasonography and changes in cerebral oxygenation) to reduce bias arising from the placebo effect. We will use metabolomics to investigate the mechanisms

  10. Sequential processing during noun phrase production.

    Science.gov (United States)

    Bürki, Audrey; Sadat, Jasmin; Dubarry, Anne-Sophie; Alario, F-Xavier

    2016-01-01

    This study examined whether the brain operations involved during the processing of successive words in multi word noun phrase production take place sequentially or simultaneously. German speakers named pictures while ignoring a written distractor superimposed on the picture (picture-word interference paradigm) using the definite determiner and corresponding German noun. The gender congruency and the phonological congruency (i.e., overlap in first phonemes) between target and distractor were manipulated. Naming responses and EEG were recorded. The behavioural performance replicated both the phonology and the gender congruency effects (i.e., shorter naming latencies for gender congruent than incongruent and for phonologically congruent than incongruent trials). The phonological and gender manipulations also influenced the EEG data. Crucially, the two effects occurred in different time windows and over different sets of electrodes. The phonological effect was observed substantially earlier than the gender congruency effect. This finding suggests that the processing of determiners and nouns during determiner noun phrase production occurs at least partly sequentially. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Dating phylogenies with sequentially sampled tips.

    Science.gov (United States)

    Stadler, Tanja; Yang, Ziheng

    2013-09-01

    We develop a Bayesian Markov chain Monte Carlo (MCMC) algorithm for estimating divergence times using sequentially sampled molecular sequences. This type of data is commonly collected during viral epidemics and is sometimes available from different species in ancient DNA studies. We derive the distribution of ages of nodes in the tree under a birth-death-sequential-sampling (BDSS) model and use it as the prior for divergence times in the dating analysis. We implement the prior in the MCMCtree program in the PAML package for divergence dating. The BDSS prior is very flexible and, with different parameters, can generate trees of very different shapes, suitable for examining the sensitivity of posterior time estimates. We apply the method to a data set of SIV/HIV-2 genes in comparison with a likelihood-based dating method, and to a data set of influenza H1 genes from different hosts in comparison with the Bayesian program BEAST. We examined the impact of tree topology on time estimates and suggest that multifurcating consensus trees should be avoided in dating analysis. We found posterior time estimates for old nodes to be sensitive to the priors on times and rates and suggest that previous Bayesian dating studies may have produced overconfident estimates.

  12. Comparison of Sequential and Variational Data Assimilation

    Science.gov (United States)

    Alvarado Montero, Rodolfo; Schwanenberg, Dirk; Weerts, Albrecht

    2017-04-01

    Data assimilation is a valuable tool to improve model state estimates by combining measured observations with model simulations. It has recently gained significant attention due to its potential in using remote sensing products to improve operational hydrological forecasts and for reanalysis purposes. This has been supported by the application of sequential techniques such as the Ensemble Kalman Filter which require no additional features within the modeling process, i.e. it can use arbitrary black-box models. Alternatively, variational techniques rely on optimization algorithms to minimize a pre-defined objective function. This function describes the trade-off between the amount of noise introduced into the system and the mismatch between simulated and observed variables. While sequential techniques have been commonly applied to hydrological processes, variational techniques are seldom used. In our believe, this is mainly attributed to the required computation of first order sensitivities by algorithmic differentiation techniques and related model enhancements, but also to lack of comparison between both techniques. We contribute to filling this gap and present the results from the assimilation of streamflow data in two basins located in Germany and Canada. The assimilation introduces noise to precipitation and temperature to produce better initial estimates of an HBV model. The results are computed for a hindcast period and assessed using lead time performance metrics. The study concludes with a discussion of the main features of each technique and their advantages/disadvantages in hydrological applications.

  13. Noncommutative Biology: Sequential Regulation of Complex Networks.

    Directory of Open Access Journals (Sweden)

    William Letsou

    2016-08-01

    Full Text Available Single-cell variability in gene expression is important for generating distinct cell types, but it is unclear how cells use the same set of regulatory molecules to specifically control similarly regulated genes. While combinatorial binding of transcription factors at promoters has been proposed as a solution for cell-type specific gene expression, we found that such models resulted in substantial information bottlenecks. We sought to understand the consequences of adopting sequential logic wherein the time-ordering of factors informs the final outcome. We showed that with noncommutative control, it is possible to independently control targets that would otherwise be activated simultaneously using combinatorial logic. Consequently, sequential logic overcomes the information bottleneck inherent in complex networks. We derived scaling laws for two noncommutative models of regulation, motivated by phosphorylation/neural networks and chromosome folding, respectively, and showed that they scale super-exponentially in the number of regulators. We also showed that specificity in control is robust to the loss of a regulator. Lastly, we connected these theoretical results to real biological networks that demonstrate specificity in the context of promiscuity. These results show that achieving a desired outcome often necessitates roundabout steps.

  14. Sequential evidence accumulation in decision making

    Directory of Open Access Journals (Sweden)

    Daniel Hausmann

    2008-03-01

    Full Text Available Judgments and decisions under uncertainty are frequently linked to a prior sequential search for relevant information. In such cases, the subject has to decide when to stop the search for information. Evidence accumulation models from social and cognitive psychology assume an active and sequential information search until enough evidence has been accumulated to pass a decision threshold. In line with such theories, we conceptualize the evidence threshold as the ``desired level of confidence'' (DLC of a person. This model is tested against a fixed stopping rule (one-reason decision making and against the class of multi-attribute information integrating models. A series of experiments using an information board for horse race betting demonstrates an advantage of the proposed model by measuring the individual DLC of each subject and confirming its correctness in two separate stages. In addition to a better understanding of the stopping rule (within the narrow framework of simple heuristics, the results indicate that individual aspiration levels might be a relevant factor when modelling decision making by task analysis of statistical environments.

  15. Hybrid Computerized Adaptive Testing: From Group Sequential Design to Fully Sequential Design

    Science.gov (United States)

    Wang, Shiyu; Lin, Haiyan; Chang, Hua-Hua; Douglas, Jeff

    2016-01-01

    Computerized adaptive testing (CAT) and multistage testing (MST) have become two of the most popular modes in large-scale computer-based sequential testing. Though most designs of CAT and MST exhibit strength and weakness in recent large-scale implementations, there is no simple answer to the question of which design is better because different…

  16. A randomized clinical trial of neurally adjusted ventilatory assist versus conventional weaning mode in patients with COPD and prolonged mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Kuo NY

    2016-05-01

    Full Text Available Nai-Ying Kuo,1,2 Mei-Lien Tu,1,3 Tsai-Yi Hung,1 Shih-Feng Liu,4 Yu-Hsiu Chung,4 Meng-Chih Lin,4 Chao-Chien Wu41Department of Respiratory Therapy, Kaohsiung Chang Gung Memorial Hospital; 2Kaohsiung Medical University; 3Respiratory Care, Chang Gung University of Science and Technology, Chiayi, Taiwan; 4Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, TaiwanBackground: Patient-ventilator asynchrony is a common problem in mechanically ventilated patients; the problem is especially obvious in COPD. Neutrally adjusted ventilatory assist (NAVA can improve patient-ventilator asynchrony; however, the effect in COPD patients with prolonged mechanical ventilation is still unknown. The goals of this study are to evaluate the effect of NAVA and conventional weaning mode in patients with COPD during prolonged mechanical ventilation.Methods: The study enrolled a total of 33 COPD patients with ventilator dependency for more than 21 days in the weaning center. A diaphragm electrical activity (Edi catheter was inserted in patients within 24 hours after admission to the respiratory care center, and patients were randomly allocated to NAVA or conventional group. A spontaneous breathing trial was performed every 24 hours. The results correlated with the clinical parameters.Results: There were significantly higher asynchrony incidence rates in the whole group after using Edi catheter (before vs post-Edi catheter insertion =60.6% vs 87.9%, P<0.001. Asynchrony index: before vs post-Edi catheter insertion =7.4%±8.5% vs 13.2%±13.5%, P<0.01. Asynchrony incidence: NAVA vs conventional =0% vs 84.2%, P<0.001. Asynchrony index: NAVA vs conventional =0 vs 11.9±11.2 (breath %, P<0.001. The most common asynchrony events were ineffective trigger and delayed trigger. Conclusion: Compared to conventional mode, NAVA mode can significantly enhance

  17. Efficacy of kinesio taping versus postural correction exercises on pain intensity and axioscapular muscles activation in mechanical neck dysfunction: a randomized blinded clinical trial.

    Science.gov (United States)

    El-Abd, Aliaa M; Ibrahim, Abeer R; El-Hafez, Haytham M

    2017-10-01

    While postural correction is commonly used for mechanical neck dysfunction (MND), efficacy of KT has received considerable attention. This study was conducted to determine the effectiveness of kinesio taping (KT) versus postural correction exercises on pain intensity and axioscapular muscles activation in patients with MND. Randomized clinical trial for which forty six patients with MND were randomly assigned in to 1 of 2 groups received 4 weeks treatment; KT group: received kinesio taping, PCE group: performed postural correction exercises. Neck pain and axioscapular muscles activation in form of normalized root mean square of dominant upper trapezius and levator scapula muscles were measured pre- and post-treatment by visual analogue scale and electromyography. Two ways MANOVA was used to examine the effects of treatment on outcome measures. The variable of interest was the group-by-time interaction at an a priori alpha level of 0.05. Intragroup comparisons were performed using paired t-tests. Group by time interaction was statistically significant in multivariate test (F=3.114, P=0.031). KT produced more pain reduction than postural exercises (P<0.05). There was no significant interaction for either UT RMS (P=0.274) or LS RMS (P=0.59). In both groups, Paired t tests revealed that there was significant reduction in pain and muscle activation of both measured muscles (P<0.01). KT has been found to be more effective than postural exercises to reduce neck pain. However, both modalities have similar effects to reduce axioscapular muscles activation.

  18. Magnetic Resonance Imaging Zygapophyseal Joint Space Changes (Gapping) in Low Back Pain Patients following Spinal Manipulation and Side Posture Positioning: A Randomized Controlled Mechanisms Trial with Blinding

    Science.gov (United States)

    Cramer, Gregory D.; Cambron, Jerrilyn; Cantu, Joe A; Dexheimer, Jennifer M.; Pocius, Judith D; Gregerson, Douglas; Fergus, Michael; McKinnis, Ray; Grieve, Thomas J

    2013-01-01

    Objective The purpose of this study was to quantify lumbar zygapophyseal (Z) joint space separation (gapping) in low back pain (LBP) subjects after spinal manipulative therapy (SMT) or side-posture positioning (SPP). Methods This was a controlled mechanisms trial with randomization and blinding. Acute LBP subjects (N=112, four n=28 MRI protocol groups) had 2 magnetic resonance imaging (MRI) appointments (initial enrollment [M1] and following 2 weeks of chiropractic treatment [M2]; receiving 2 MRI scans of the L4/L5 and L5/S1 Z joints at each MRI appointment. After the first MRI scan of each appointment, subjects were randomized (M1 appointment) or assigned (M2 appointment) into SPP (non-manipulation), SMT (manipulation), or control MRI protocol groups. After SPP or SMT, a second MRI was taken. The central anterior-posterior (A-P) joint space was measured. Difference between most painful side A-P measurements taken post- and pre-intervention was the Z joint “gapping difference.” Gapping differences were compared (ANOVA) among protocol groups. Secondary measures of pain visual analog scale (VAS), verbal numeric pain rating scale (VNPRS), and function Bournemouth questionnaire (BQ) were assessed. Results Gapping differences were significant at the first (adjusted, p=0.01; SPP=0.66 +0.48mm; SMT=0.23 +0.86; control=0.18 +0.71) and second (adjusted, p=0.0005; SPP=0.65 +0.92mm, SMT=0.89 +0.71; control=0.35 +0.32) MRI appointments. VNPRS differences were significant at first MRI appointment (p=0.04) with SMT showing the greatest improvement. VAS and BQ improved after two weeks of care in all groups (both p<0.0001). Conclusions SPP showed greatest gapping at baseline. After two weeks, SMT resulted in greatest gapping. SPP appeared to have additive therapeutic benefit to SMT. PMID:23648055

  19. Preemptive Behavior in Sequential-Move Tournaments with Heterogeneous Agents

    OpenAIRE

    Jost, Peter-Jürgen; Kräkel, Matthias

    2004-01-01

    Rank-order tournaments are usually modeled simultaneously. However, real tournaments are often sequential. We show that agents? strategic behavior in sequential-move tournaments significantly differ from the one in simultaneous-move tournaments: In a sequential-move tournament with heterogeneous agents, there may be either a first-mover or a second-mover advantage. Under certain conditions the first acting agent chooses a preemptively high effort so that the following agent gives up. The prin...

  20. [Sequential reduction and fixation for zygomatic complex fractures].

    Science.gov (United States)

    Yang, Lijuan; Liu, Chunming; Hua, Wenmei; Liu, Weidong; Wang, Xiguang; Wang, Kai; Zhang, Zhanle; Li, Meifang; Duan, Hainan

    2013-10-01

    To explore the procedure and effectiveness of sequential reduction and fixation for zygomatic complex fractures. Between March 2004 and February 2012, 32 patients with zygomatic complex fractures were treated. There were 28 males and 4 females with a median age of 29 years (range, 17-55 years). Fractures were caused by traffic accident in 29 cases and by tumble in 3 cases. The time between injury and admission was 1-12 days (mean, 3 days) in 28 fresh fractures and 22-60 days (mean, 40 days) in 4 old fractures. All patients were diagnosed by clinical symptom and CT scan. Coronal scalp incision, lower eyelid aesthetic incision, and intraoral incision were used to expose the zygomatic bone segments. The sequence of fractures reduction and fixation was horizontal first, and then longitudinal. In horizontal orientation, reduction and simultaneous fixation started from the root of the zygoma, to zygomatic arch, body of the zygoma, and inferior orbital rim in turn. Longitudinally, fracture reduction of zygomatico-frontal suture and orbital posterolateral walls was done first, followed by fracture reduction of zygomaticomaxillary buttress. Primary healing of incision was obtained in all 32 cases, without complications of maxillary sinus fistula and infection. Eighteen patients were followed up 6 months to 6 years with a median time of 32 months. All the patients gained satisfactory results with normal zygomatic contour and symmetric midface. All patients restored normal mouth opening. No eye and vision damage occurred. Frontal disappearance and brow ptosis were observed in 2 cases. Hair loss (2-3 mm) was seen at the site of coronal scalp incision, without scar hyperplasia; there was no obvious scar at lower eyelid. CT and X-ray films showed bony healing at 6 months after operation. Sequential reduction and fixation is accord with the mechanical characters of complicated zygomatic fractures. It is very easy to achieve anatomic reduction of the bone segments and facial

  1. Sequential vs alternating administration of VMP and Rd in elderly patients with newly diagnosed MM.

    Science.gov (United States)

    Mateos, María-Victoria; Martínez-López, Joaquín; Hernández, Miguel-Teodoro; Ocio, Enrique-M; Rosiñol, Laura; Martínez, Rafael; Teruel, Ana-Isabel; Gutiérrez, Norma C; Martín Ramos, María-Luisa; Oriol, Albert; Bargay, Joan; Bengoechea, Enrique; González, Yolanda; Pérez de Oteyza, Jaime; Gironella, Mercedes; Encinas, Cristina; Martín, Jesús; Cabrera, Carmen; Paiva, Bruno; Cedena, María-Teresa; Puig, Noemí; Bladé, Joan; Lahuerta, Juan-José; San-Miguel, Jesús

    2016-01-28

    Bortezomib plus melphalan and prednisone (VMP) and lenalidomide plus low-dose dexamethasone (Rd) are 2 standards of care for elderly untreated multiple myeloma (MM) patients. We planned to use VMP and Rd for 18 cycles in a sequential or alternating scheme. Patients (233) with untreated MM, >65 years, were randomized to receive 9 cycles of VMP followed by 9 cycles of Rd (sequential scheme; n = 118) vs 1 cycle of VMP followed by 1 cycle of Rd, and so on, up to 18 cycles (alternating scheme; n = 115). VMP consisted of one 6-week cycle of bortezomib using a biweekly schedule, followed by eight 5-week cycles of once-weekly VMP. Rd included nine 4-week cycles of Rd. The primary end points were 18-month progression free survival (PFS) and safety profile of both schemes. The 18-month PFS was 74% and 80% in the sequential and alternating arms, respectively (P = .21). The sequential and alternating groups exhibited similar hematologic and nonhematologic toxicity. Both arms yielded similar complete response rate (42% and 40%), median PFS (32 months vs 34 months, P = .65), and 3-year overall survival (72% vs 74%, P = .63). The benefit of both schemes was remarkable in patients aged 65 to 75 years. In addition, achieving complete and immunophenotypic response was associated with better outcome. The present approach, based on VMP and Rd, is associated with high efficacy and acceptable toxicity profile with no differences between the sequential and alternating regimens. This trial was registered at www.clinicaltrials.gov as #NCT00443235. © 2016 by The American Society of Hematology.

  2. A randomized clinical trial of the effectiveness of mechanical traction for sub-groups of patients with low back pain: study methods and rationale

    Directory of Open Access Journals (Sweden)

    Thackeray Anne

    2010-04-01

    Full Text Available Abstract Background Patients with signs of nerve root irritation represent a sub-group of those with low back pain who are at increased risk of persistent symptoms and progression to costly and invasive management strategies including surgery. A period of non-surgical management is recommended for most patients, but there is little evidence to guide non-surgical decision-making. We conducted a preliminary study examining the effectiveness of a treatment protocol of mechanical traction with extension-oriented activities for patients with low back pain and signs of nerve root irritation. The results suggested this approach may be effective, particularly in a more specific sub-group of patients. The aim of this study will be to examine the effectiveness of treatment that includes traction for patients with low back pain and signs of nerve root irritation, and within the pre-defined sub-group. Methods/Design The study will recruit 120 patients with low back pain and signs of nerve root irritation. Patients will be randomized to receive an extension-oriented treatment approach, with or without the addition of mechanical traction. Randomization will be stratified based on the presence of the pre-defined sub-grouping criteria. All patients will receive 12 physical therapy treatment sessions over 6 weeks. Follow-up assessments will occur after 6 weeks, 6 months, and 1 year. The primary outcome will be disability measured with a modified Oswestry questionnaire. Secondary outcomes will include self-reports of low back and leg pain intensity, quality of life, global rating of improvement, additional healthcare utilization, and work absence. Statistical analysis will be based on intention to treat principles and will use linear mixed model analysis to compare treatment groups, and examine the interaction between treatment and sub-grouping status. Discussion This trial will provide a methodologically rigorous evaluation of the effectiveness of using traction

  3. Manual Cardiopulmonary Resuscitation Versus CPR Including a Mechanical Chest Compression Device in Out-of-Hospital Cardiac Arrest: A Comprehensive Meta-analysis From Randomized and Observational Studies.

    Science.gov (United States)

    Bonnes, Judith L; Brouwer, Marc A; Navarese, Eliano P; Verhaert, Dominique V M; Verheugt, Freek W A; Smeets, Joep L R M; de Boer, Menko-Jan

    2016-03-01

    Mechanical chest compression devices have been developed to facilitate continuous delivery of high-quality cardiopulmonary resuscitation (CPR). Despite promising hemodynamic data, evidence on clinical outcomes remains inconclusive. With the completion of 3 randomized controlled trials, we conduct a meta-analysis on the effect of in-field mechanical versus manual CPR on clinical outcomes after out-of-hospital cardiac arrest. With a systematic search (PubMed, Web of Science, EMBASE, and the Cochrane Libraries), we identified all eligible studies (randomized controlled trials and nonrandomized studies) that compared a CPR strategy including an automated mechanical chest compression device with a strategy of manual CPR only. Outcome variables were survival to hospital admission, survival to discharge, and favorable neurologic outcome. Twenty studies (n=21,363) were analyzed: 5 randomized controlled trials and 15 nonrandomized studies, pooled separately. For survival to admission, the pooled estimate of the randomized controlled trials did not indicate a difference (odds ratio 0.94; 95% confidence interval 0.84 to 1.05; P=.24) between mechanical and manual CPR. In contrast, meta-analysis of nonrandomized studies demonstrated a benefit in favor of mechanical CPR (odds ratio 1.42; 95% confidence interval 1.21 to 1.67; PCPR guidelines (2000 versus 2005) and the CPR strategy (P=.27). Survival to discharge and neurologic outcome did not differ between strategies. Although there are lower-quality, observational data that suggest that mechanical CPR used at the rescuer's discretion could improve survival to hospital admission, the cumulative high-quality randomized evidence does not support a routine strategy of mechanical CPR to improve survival or neurologic outcome. These findings are irrespective of the endorsed CPR guidelines during the study periods. Copyright © 2015 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.

  4. Multilevel sequential Monte-Carlo samplers

    KAUST Repository

    Jasra, Ajay

    2016-01-05

    Multilevel Monte-Carlo methods provide a powerful computational technique for reducing the computational cost of estimating expectations for a given computational effort. They are particularly relevant for computational problems when approximate distributions are determined via a resolution parameter h, with h=0 giving the theoretical exact distribution (e.g. SDEs or inverse problems with PDEs). The method provides a benefit by coupling samples from successive resolutions, and estimating differences of successive expectations. We develop a methodology that brings Sequential Monte-Carlo (SMC) algorithms within the framework of the Multilevel idea, as SMC provides a natural set-up for coupling samples over different resolutions. We prove that the new algorithm indeed preserves the benefits of the multilevel principle, even if samples at all resolutions are now correlated.

  5. Prosody and alignment: a sequential perspective

    Science.gov (United States)

    Szczepek Reed, Beatrice

    2010-12-01

    In their analysis of a corpus of classroom interactions in an inner city high school, Roth and Tobin describe how teachers and students accomplish interactional alignment by prosodically matching each other's turns. Prosodic matching, and specific prosodic patterns are interpreted as signs of, and contributions to successful interactional outcomes and positive emotions. Lack of prosodic matching, and other specific prosodic patterns are interpreted as features of unsuccessful interactions, and negative emotions. This forum focuses on the article's analysis of the relation between interpersonal alignment, emotion and prosody. It argues that prosodic matching, and other prosodic linking practices, play a primarily sequential role, i.e. one that displays the way in which participants place and design their turns in relation to other participants' turns. Prosodic matching, rather than being a conversational action in itself, is argued to be an interactional practice (Schegloff 1997), which is not always employed for the accomplishment of `positive', or aligning actions.

  6. Dihydroazulene photoswitch operating in sequential tunneling regime

    DEFF Research Database (Denmark)

    Broman, Søren Lindbæk; Lara-Avila, Samuel; Thisted, Christine Lindbjerg

    2012-01-01

    Molecular switches play a central role for the development of molecular electronics. In this work it is demonstrated that the reproducibility and robustness of a single-molecule dihydroazulene (DHA)/vinylheptafulvene (VHF) switch can be remarkably enhanced if the switching kernel is weakly coupled...... to electrodes so that the electron transport goes by sequential tunneling. To assure weak coupling, the DHA switching kernel is modified by incorporating p-MeSC6H4 end-groups. Molecules are prepared by Suzuki cross-couplings on suitable halogenated derivatives of DHA. The synthesis presents an expansion of our...... previously reported brominationeliminationcross-coupling protocol for functionalization of the DHA core. For all new derivatives the kinetics of DHA/VHF transition has been thoroughly studied in solution. The kinetics reveals the effect of sulfur end-groups on the thermal ring-closure of VHF. One derivative...

  7. Prototype color field sequential television lens assembly

    Science.gov (United States)

    1974-01-01

    The design, development, and evaluation of a prototype modular lens assembly with a self-contained field sequential color wheel is presented. The design of a color wheel of maximum efficiency, the selection of spectral filters, and the design of a quiet, efficient wheel drive system are included. Design tradeoffs considered for each aspect of the modular assembly are discussed. Emphasis is placed on achieving a design which can be attached directly to an unmodified camera, thus permitting use of the assembly in evaluating various candidate camera and sensor designs. A technique is described which permits maintaining high optical efficiency with an unmodified camera. A motor synchronization system is developed which requires only the vertical synchronization signal as a reference frequency input. Equations and tradeoff curves are developed to permit optimizing the filter wheel aperture shapes for a variety of different design conditions.

  8. Sequential infiltration synthesis for advanced lithography

    Energy Technology Data Exchange (ETDEWEB)

    Darling, Seth B.; Elam, Jeffrey W.; Tseng, Yu-Chih; Peng, Qing

    2017-10-10

    A plasma etch resist material modified by an inorganic protective component via sequential infiltration synthesis (SIS) and methods of preparing the modified resist material. The modified resist material is characterized by an improved resistance to a plasma etching or related process relative to the unmodified resist material, thereby allowing formation of patterned features into a substrate material, which may be high-aspect ratio features. The SIS process forms the protective component within the bulk resist material through a plurality of alternating exposures to gas phase precursors which infiltrate the resist material. The plasma etch resist material may be initially patterned using photolithography, electron-beam lithography or a block copolymer self-assembly process.

  9. Sequential Stereotype Priming: A Meta-Analysis.

    Science.gov (United States)

    Kidder, Ciara K; White, Katherine R; Hinojos, Michelle R; Sandoval, Mayra; Crites, Stephen L

    2017-08-01

    Psychological interest in stereotype measurement has spanned nearly a century, with researchers adopting implicit measures in the 1980s to complement explicit measures. One of the most frequently used implicit measures of stereotypes is the sequential priming paradigm. The current meta-analysis examines stereotype priming, focusing specifically on this paradigm. To contribute to ongoing discussions regarding methodological rigor in social psychology, one primary goal was to identify methodological moderators of the stereotype priming effect-whether priming is due to a relation between the prime and target stimuli, the prime and target response, participant task, stereotype dimension, stimulus onset asynchrony (SOA), and stimuli type. Data from 39 studies yielded 87 individual effect sizes from 5,497 participants. Analyses revealed that stereotype priming is significantly moderated by the presence of prime-response relations, participant task, stereotype dimension, target stimulus type, SOA, and prime repetition. These results carry both practical and theoretical implications for future research on stereotype priming.

  10. Sequential pattern formation governed by signaling gradients

    CERN Document Server

    Jörg, David J; Jülicher, Frank

    2016-01-01

    Rhythmic and sequential segmentation of the embryonic body plan is a vital developmental patterning process in all vertebrate species. However, a theoretical framework capturing the emergence of dynamic patterns of gene expression from the interplay of cell oscillations with tissue elongation and shortening and with signaling gradients, is still missing. Here we show that a set of coupled genetic oscillators in an elongating tissue that is regulated by diffusing and advected signaling molecules can account for segmentation as a self-organized patterning process. This system can form a finite number of segments and the dynamics of segmentation and the total number of segments formed depend strongly on kinetic parameters describing tissue elongation and signaling molecules. The model accounts for existing experimental perturbations to signaling gradients, and makes testable predictions about novel perturbations. The variety of different patterns formed in our model can account for the variability of segmentatio...

  11. Sequential cooling insert for turbine stator vane

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Russel B

    2017-04-04

    A sequential flow cooling insert for a turbine stator vane of a small gas turbine engine, where the impingement cooling insert is formed as a single piece from a metal additive manufacturing process such as 3D metal printing, and where the insert includes a plurality of rows of radial extending impingement cooling air holes alternating with rows of radial extending return air holes on a pressure side wall, and where the insert includes a plurality of rows of chordwise extending second impingement cooling air holes on a suction side wall. The insert includes alternating rows of radial extending cooling air supply channels and return air channels that form a series of impingement cooling on the pressure side followed by the suction side of the insert.

  12. Compound imaging using Synthetic Aperture Sequential Beamformation

    DEFF Research Database (Denmark)

    Jensen, Casper Bo; Jensen, Jonas; Hemmsen, Martin Christian

    2011-01-01

    Synthetic Aperture Sequential Beamforming (SASB) is a technique with low complexity and the ability to yield a more uniform lateral resolution with range. However, the presence of speckle artifacts in ultrasound images degrades the contrast. In conventional imaging speckle is reduced by using...... spatial compounding at the cost of a reduced frame rate. The objective is to apply spatial compounding to SASB and evaluate if the images have a reduced speckle appearance and thereby an improved image quality in terms of contrast compared to ordinary SASB. Using the simulation software Field II, RF data...... detection the five second stage images are added to form the compounded image. Using a ProFocus scanner and the 8804 linear array transducer (BK Medical, Herlev, Denmark) measurements of a phantom containing water filled cysts are obtained to validate the simulation results. The setup is the same...

  13. Isoscaling in Statistical Sequential Decay Model

    Science.gov (United States)

    Tian, Wen-Dong; Ma, Yu-Gang; Cai, Xiang-Zhou; Fang, De-Qing; Guo, Wei; Ma, Chun-Wang; Liu, Gui-Hua; Shen, Wen-Qing; Shi, Yu; Su, Qian-Min; Wang, Hong-Wei; Wang, Kun; Yan, Ting-Zhi

    2007-02-01

    A sequential decay model is used to study isoscaling, i.e. the factorization of the isotope ratios from sources of different isospins and sizes over a broad range of excitation energies, into fugacity terms of proton and neutron number, R21(N,Z) = Y2(N,Z)/Y1(N,Z) = Ce(αN+βZ). It is found that the isoscaling parameters α and β have a strong dependence on the isospin difference of equilibrated source and excitation energy, no significant influence of the source size on α and β has been observed. It is found that α and β decrease with the excitation energy and are linear functions of 1/T and Δ(Z/A)2 or Δ(N/A)2 of the sources. Symmetry energy coefficient Csym is constrained from the relationship of α and source Δ(Z/A)2, β and source Δ(N/A)2.

  14. Composite SAR imaging using sequential joint sparsity

    Science.gov (United States)

    Sanders, Toby; Gelb, Anne; Platte, Rodrigo B.

    2017-06-01

    This paper investigates accurate and efficient ℓ1 regularization methods for generating synthetic aperture radar (SAR) images. Although ℓ1 regularization algorithms are already employed in SAR imaging, practical and efficient implementation in terms of real time imaging remain a challenge. Here we demonstrate that fast numerical operators can be used to robustly implement ℓ1 regularization methods that are as or more efficient than traditional approaches such as back projection, while providing superior image quality. In particular, we develop a sequential joint sparsity model for composite SAR imaging which naturally combines the joint sparsity methodology with composite SAR. Our technique, which can be implemented using standard, fractional, or higher order total variation regularization, is able to reduce the effects of speckle and other noisy artifacts with little additional computational cost. Finally we show that generalizing total variation regularization to non-integer and higher orders provides improved flexibility and robustness for SAR imaging.

  15. Merging particle filter for sequential data assimilation

    Directory of Open Access Journals (Sweden)

    S. Nakano

    2007-07-01

    Full Text Available A new filtering technique for sequential data assimilation, the merging particle filter (MPF, is proposed. The MPF is devised to avoid the degeneration problem, which is inevitable in the particle filter (PF, without prohibitive computational cost. In addition, it is applicable to cases in which a nonlinear relationship exists between a state and observed data where the application of the ensemble Kalman filter (EnKF is not effectual. In the MPF, the filtering procedure is performed based on sampling of a forecast ensemble as in the PF. However, unlike the PF, each member of a filtered ensemble is generated by merging multiple samples from the forecast ensemble such that the mean and covariance of the filtered distribution are approximately preserved. This merging of multiple samples allows the degeneration problem to be avoided. In the present study, the newly proposed MPF technique is introduced, and its performance is demonstrated experimentally.

  16. The sequential propensity household projection model

    Directory of Open Access Journals (Sweden)

    Tom Wilson

    2013-04-01

    Full Text Available BACKGROUND The standard method of projecting living arrangements and households in Australia and New Zealand is the 'propensity model', a type of extended headship rate model. Unfortunately it possesses a number of serious shortcomings, including internal inconsistencies, difficulties in setting living arrangement assumptions, and very limited scenario creation capabilities. Data allowing the application of more sophisticated dynamic household projection models are unavailable in Australia. OBJECTIVE The aim was create a projection model to overcome these shortcomings whilst minimising input data requirements and costs, and retaining the projection outputs users are familiar with. METHODS The sequential propensity household projection model is proposed. Living arrangement projections take place in a sequence of calculations, with progressively more detailed living arrangement categories calculated in each step. In doing so the model largely overcomes the three serious deficiencies of the standard propensity model noted above. RESULTS The model is illustrated by three scenarios produced for one case study State, Queensland. They are: a baseline scenario in which all propensities are held constant to demonstrate the effects of population growth and ageing, a housing crisis scenario where housing affordability declines, and a prosperity scenario where families and individuals enjoy greater real incomes. A sensitivity analysis in which assumptions are varied one by one is also presented. CONCLUSIONS The sequential propensity model offers a more effective method of producing household and living arrangement projections than the standard propensity model, and is a practical alternative to dynamic projection models for countries and regions where the data and resources to apply such models are unavailable.

  17. The timing of tracheotomy in critically ill patients undergoing mechanical ventilation: a systematic review and meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Wang, Fei; Wu, Youping; Bo, Lulong; Lou, Jingsheng; Zhu, Jiali; Chen, Feng; Li, Jinbao; Deng, Xiaoming

    2011-12-01

    The objective of this study was to systematically review and quantitatively synthesize all randomized controlled trials (RCTs), comparing important outcomes in ventilated critically ill patients who received an early or late tracheotomy. A systematic literature search of PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Embase, the Cochrane Central Register of Controlled Trials, the National Research Register, the National Health Service Trusts Clinical Trials Register, and the Medical Research Council UK database was conducted using specific search terms. Eligible studies were RCTs that compared early tracheotomy (ET) with either late tracheotomy or prolonged endotracheal intubation in critically ill adult patients. Seven trials with 1,044 patients were analyzed. ET did not significantly reduce short-term mortality (relative risk [RR], 0.86; 95% CI, 0.65-1.13), long-term mortality (RR, 0.84; 95% CI, 0.68-1.04), or incidence of ventilator-associated pneumonia (RR, 0.94; 95% CI, 0.77-1.15) in critically ill patients. The timing of the tracheotomy was not associated with a markedly reduced duration of mechanical ventilation (MV) (weighted mean difference [WMD], -3.90 days; 95% CI, -9.71-1.91) or sedation (WMD, -7.09 days; 95% CI, -14.64-0.45), shorter stay in ICU (WMD, -6.93 days; 95% CI, -16.50-2.63) or hospital (WMD, 1.45 days; 95% CI, -5.31-8.22), or more complications (RR, 0.94; 95% CI, 0.66-1.34). The present meta-analysis suggested that the timing of the tracheotomy did not significantly alter important clinical outcomes in critically ill patients. The duration of MV and sedation, as well as the long-term outcomes of ET in mechanically ventilated patients, should be evaluated in rigorously designed and adequately powered RCTs in the future.

  18. Isotope partitioning in the adenosine 3',5'-monophosphate dependent protein kinase reaction indicates a steady-state random kinetic mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Kong, C.T.; Cook, P.F.

    1988-06-28

    Isotope partitioning beginning with the binary E.MgATP and E.N-acetyl-Leu-Arg-Arg-Ala-Ser-Leu-Gly (Ser-peptide) complexes indicates that the kinetic mechanism for the adenosine 3',5'-monophosphate dependent protein kinase is steady-state random. A total of 100% of the initial radioactive E.MgATP complex is trapped as phospho-Ser-peptide at infinite Ser-peptide concentration at both low and high concentration of uncomplexed Mg2+, suggesting that the off-rate of MgATP from the E.MgATP.Ser-peptide complex is slow relative to the catalytic steps. Km for Ser-peptide in the trapping reaction decreases from 17 microM at low Mg2+ to 2 microM at high Mg2+, indicating that Mg2+ decreases the off-rate for MgATP from the E.MgATP complex. A total of 100% of the radioactive E.Ser-peptide complex is trapped as phospho-Ser-peptide at low Mg2+, but only 40% is trapped at high Mg2+ in the presence of an infinite concentration of MgATP, suggesting that the off-rate for Ser-peptide from the central complex is much less than catalysis at low but not at high Mg2+. In support of this finding, the Ki for Leu-Arg-Arg-Ala-Ala-Leu-Gly (Ala-peptide) increases from 0.27 mM at low Mg2+ to 2.4 mM at high Mg2+. No trapping was observed at either high or low Mg2+ for the E.MgADP complex up to a phospho-Ser-peptide concentration of 5 mM. Thus, it is likely that in the slow-reaction direction the kinetic mechanism is rapid equilibrium.

  19. Sodium hyaluronate eye drops treatment for superficial corneal abrasion caused by mechanical damage: a randomized clinical trial in the People’s Republic of China

    Science.gov (United States)

    Lin, Tong; Gong, Lan

    2015-01-01

    Purpose To evaluate the effectiveness and safety of 0.3% sodium hyaluronate (HA) compared to recombinant bovine basic fibroblast growth factor (rb-bFGF) for the treatment of corneal epithelial abrasion caused by mechanical damage in Chinese patients. Methods Thirty patients were randomly assigned to the HA or rb-bFGF treatment group. The HA group was treated with 0.3% HA and 0.5% levofloxacin, and the rb-bFGF group was treated with topical rb-bFGF and 0.5% levofloxacin. The primary endpoint was the clinical effectiveness rates at day 3. Secondary endpoints were the dimensions of the wound area and the percentage of wound closure. Results After 3 days of treatment, the clinical effectiveness rates of the HA group and the rb-bFGF group were 86.67% (13/15) and 93.33% (14/15), respectively. The dimensions of the wound area were reduced from 9.83±8.50 to 0.02±0.06 mm2 for the HA group at day 7, and from 10.58±9.94 to 0.02±0.07 mm2 for the rb-bFGF group. At day 3, the wound closure was almost complete in both groups; 94.73% in the HA group compared to 95.77% in the rb-bFGF group (P>0.05). Conclusion Topical 0.3% HA provided a promising treatment for superficial corneal abrasion caused by mechanical damage in a manner similar to rb-bFGF. PMID:25678773

  20. Sodium hyaluronate eye drops treatment for superficial corneal abrasion caused by mechanical damage: a randomized clinical trial in the People’s Republic of China

    Directory of Open Access Journals (Sweden)

    Lin T

    2015-01-01

    Full Text Available Tong Lin, Lan Gong Department of Ophthalmology, Eye and ENT Hospital of Fudan University, Shanghai, People’s Republic of China Purpose: To evaluate the effectiveness and safety of 0.3% sodium hyaluronate (HA compared to recombinant bovine basic fibroblast growth factor (rb-bFGF for the treatment of corneal epithelial abrasion caused by mechanical damage in Chinese patients.Methods: Thirty patients were randomly assigned to the HA or rb-bFGF treatment group. The HA group was treated with 0.3% HA and 0.5% levofloxacin, and the rb-bFGF group was treated with topical rb-bFGF and 0.5% levofloxacin. The primary endpoint was the clinical effectiveness rates at day 3. Secondary endpoints were the dimensions of the wound area and the percentage of wound closure.Results: After 3 days of treatment, the clinical effectiveness rates of the HA group and the rb-bFGF group were 86.67% (13/15 and 93.33% (14/15, respectively. The dimensions of the wound area were reduced from 9.83±8.50 to 0.02±0.06 mm2 for the HA group at day 7, and from 10.58±9.94 to 0.02±0.07 mm2 for the rb-bFGF group. At day 3, the wound closure was almost complete in both groups; 94.73% in the HA group compared to 95.77% in the rb-bFGF group (P>0.05.Conclusion: Topical 0.3% HA provided a promising treatment for superficial corneal abrasion caused by mechanical damage in a manner similar to rb-bFGF. Keywords: sodium hyaluronate, superficial corneal abrasion, bovine basic fibroblast growth factor

  1. Dynamic updating of numerical model discrepancy using sequential sampling

    Science.gov (United States)

    Calvetti, Daniela; Ernst, Oliver; Somersalo, Erkki

    2014-11-01

    This article addresses the problem of compensating for discretization errors in inverse problems based on partial differential equation models. Multidimensional inverse problems are by nature computationally intensive, and a key challenge in practical applications is to reduce the computing time. In particular, a reduction by coarse discretization of the forward model is commonly used. Coarse discretization, however, introduces a numerical model discrepancy, which may become the predominant part of the noise, particularly when the data is collected with high accuracy. In the Bayesian framework, the discretization error has been addressed by treating it as a random variable and using the prior density of the unknown to estimate off-line its probability density, which is then used to modify the likelihood. In this article, the problem is revisited in the context of an iterative scheme similar to Ensemble Kalman Filtering (EnKF), in which the modeling error statistics is updated sequentially based on the current ensemble estimate of the unknown quantity. Hence, the algorithm learns about the modeling error while concomitantly updating the information about the unknown, leading to a reduction of the posterior variance.

  2. An efficient approach to reliability-based design optimization within the enhanced sequential optimization and reliability assessment framework

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Hong Zhong; Zhang, Xudong; Meng, De Biao; Wang, Zhonglai; Liu, Yu [University of Electronic Science and Technology of China, Chengdu (China)

    2013-06-15

    Reliability based design optimization (RBDO) has been widely implemented in engineering practices for high safety and reliability. It is an important challenge to improve computational efficiency. Sequential optimization and reliability assessment (SORA) has made great efforts to improve computational efficiency by decoupling a RBDO problem into sequential deterministic optimization and reliability analysis as a single-loop method. In this paper, in order to further improve computational efficiency and extend the application of the current SORA method, an enhanced SORA (ESORA) is proposed by considering constant and varying variances of random design variables while keeping the sequential framework. Some mathematical examples and an engineering case are given to illustrate the proposed method and validate the efficiency.

  3. Occupational therapy for delirium management in elderly patients without mechanical ventilation in an intensive care unit: A pilot randomized clinical trial.

    Science.gov (United States)

    Álvarez, Evelyn A; Garrido, Maricel A; Tobar, Eduardo A; Prieto, Stephanie A; Vergara, Sebastian O; Briceño, Constanza D; González, Francisco J

    2017-02-01

    Delirium has negative consequences such as increased mortality, hospital expenses and decreased cognitive and functional status. This research aims to determine the impact of occupational therapy intervention in duration, incidence and severity of delirium in elderly patients in the intensive care unit; secondary outcome was to assess functionality at hospital discharge. This is a pilot randomized clinical trial of patients without mechanical ventilation for 60 years. Patients were assigned to a control group that received standard strategies of prevention (n=70) or to an experimental group that received standard strategies plus occupational therapy twice a day for 5 days (n=70). Delirium was valued with Confusion Assessment Method and Delirium Rating Scale, and functional outcomes at discharge with Functional Independence Measure, Hand Dynamometer, and Mini-Mental State Examination. A total of 140 participants were recruited. The experimental group had lower duration (risk incidence ratios, 0.15 [P=.000; 95% confidence interval, 0.12-0.19] vs 6.6 [P=.000, 95% confidence interval, 5.23-8.3]) and incidence of delirium (3% vs 20%, P=.001), and had higher scores in Motor Functional Independence Measure (59 vs 40 points, Phand (26 vs 18 kg, POccupational therapy is effective in decreasing duration and incidence of delirium in nonventilated elderly patients in the intensive care unit and improved functionality at discharge. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Efficacy in Deep Vein Thrombosis Prevention With Extended Mechanical Compression Device Therapy and Prophylactic Aspirin Following Total Knee Arthroplasty: A Randomized Control Trial.

    Science.gov (United States)

    Snyder, Mark A; Sympson, Alexandra N; Scheuerman, Christina M; Gregg, Justin L; Hussain, Lala R

    2017-05-01

    Aspirin at 325 mg twice daily is now included as a nationally approved venous thromboembolism (VTE) prophylaxis protocol for low-risk total knee arthroplasty (TKA) patients. The purpose of this study is to examine whether there is a difference in deep vein thrombosis (DVT) occurrence after a limited tourniquet TKA using aspirin-based prophylaxis with or without extended use of mechanical compression device (MCD) therapy. One hundred limited tourniquet TKA patients, whose DVT risk was managed with aspirin 325 mg twice daily for 3 weeks, were randomized to either using an MCD during hospitalization only or extended use at home up to 6 weeks postoperatively. Lower extremity duplex venous ultrasonography (LEDVU) was completed on the second postoperative day, 14 days postoperatively, and at 3 months postoperatively to confirm the absence of DVT after treatment. The DVT rate for the postdischarge MCD therapy group was 0% and 23.1% for the inpatient MCD group (P aspirin for 3 weeks postoperatively, and on MCD therapy for up to 6 weeks postoperatively experienced superior DVT prophylaxis than patients receiving MCD therapy only as an inpatient (P aspirin and extended-use MCD further validates this type of prophylaxis in low DVT risk TKA patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Internet-based instructor-led mindfulness for work-related rumination, fatigue, and sleep: Assessing facets of mindfulness as mechanisms of change. A randomized waitlist control trial.

    Science.gov (United States)

    Querstret, Dawn; Cropley, Mark; Fife-Schaw, Chris

    2017-04-01

    This study aimed to extend our theoretical understanding of how mindfulness-based interventions exert their positive influence on measures of occupational health. Employing a randomized waitlist control study design, we sought to (a) assess an Internet-based instructor-led mindfulness intervention for its effect on key factors associated with "recovery from work," specifically, work-related rumination, fatigue, and sleep quality; (b) assess different facets of mindfulness (acting with awareness, describing, nonjudging, and nonreacting) as mechanisms of change; and (c) assess whether the effect of the intervention was maintained over time by following up our participants after 3 and 6 months. Participants who completed the mindfulness intervention (n = 60) reported significantly lower levels of work-related rumination and fatigue, and significantly higher levels of sleep quality, when compared with waitlist control participants (n = 58). Effects of the intervention were maintained at 3- and 6-month follow-up with medium to large effect sizes. The effect of the intervention was primarily explained by increased levels of only 1 facet of mindfulness (acting with awareness). This study provides support for online mindfulness interventions to aid recovery from work and furthers our understanding with regard to how mindfulness interventions exert their positive effects. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  6. A Prospective, Randomized, Clinical Trial on the Effects of a Valveless Trocar on Respiratory Mechanics During Robotic Radical Cystectomy: A Pilot Study.

    Science.gov (United States)

    Covotta, Marco; Claroni, Claudia; Torregiani, Giulia; Naccarato, Alessia; Tribuzi, Susanna; Zinilli, Antonio; Forastiere, Ester

    2017-06-01

    Prolonged pneumoperitoneum and Trendelenburg positioning for robot-assisted radical cystectomy (RARC) are essential for optimizing visualization of the operative field, although they worsen hemodynamic and respiratory function. Our hypothesis is that the use of a valveless trocar (VT) may improve respiratory mechanics. In this prospective, 2-arm parallel trial, patients ASA II to III undergoing RARC were randomly assigned into 2 groups: in the VT group, the capnoperitoneum was maintained with a VT; in the control group, the capnoperitoneum was maintained with a standard trocar (ST group). Inspiratory plateau pressure (Pplat), static compliance (Cstat), minute volume (MV), tidal volume (Vt), and carbon dioxide (CO2) elimination rate were recorded at these times: 15 minutes after anesthesia induction (T0), 10 minutes (T1) and 60 minutes (T2) after first robot docking, 10 minutes before first undocking (T3), 10 minutes (T4) and 60 minutes (T5) after second docking, 10 minutes before second undocking (T6), and 10 minutes before extubation (T7). The primary end point of the study was the assessment of Pplat mean value from T1 to T6. A total of 56 patients were evaluated: 28 patients in the VT group and 28 in the ST group. VT group had lower Pplat (means and standard error, VT group 30 [0.66] versus ST group 34 [0.66] cm H2O, with estimated mean difference and 95% confidence interval, -4.1 [-5.9 to -2.2], P respiratory parameters.

  7. A randomized controlled trial of fentanyl in the pre-emptive treatment of pain associated with turning in patients under mechanical ventilation: research protocol.

    Science.gov (United States)

    Robleda, Gemma; Roche-Campo, Ferran; Urrútia, Gerard; Navarro, Marta; Sendra, Maria-Àngels; Castillo, Ana; Rodríguez-Arias, Ainhoa; Juanes-Borrejo, Elena; Gich, Ignasi; Mancebo, Jordi; Baños, Josep-E

    2015-02-01

    To compare the effectiveness and safety of fentanyl with placebo as pre-emptive treatment for pain associated with turning in patients in intensive care units. Turning is frequently a painful procedure in this setting. Pre-emptive administration of supplementary analgesia may help decrease this pain. However, medical literature on pre-emptive analgesia in these patients is scarce. A randomized, double-blind, controlled clinical trial. This study will assess the benefits and risks of pre-emptive analgesia with fentanyl compared with placebo on turning-associated pain. Eighty patients will be recruited from among those older than 18 years and needing mechanical ventilation for at least 24 hours. Pain intensity will be assessed using the Behavioral Pain Scale. Primary outcome will be pain intensity between the baseline and 30 minutes after turning, measured by the area under the curve of the pain scale scores. Secondary outcomes will be the usefulness of physiological parameters and the Bispectral Index to measure pain and the safety of pre-emptive fentanyl in turning. The study protocol was approved in February 2011. If pre-emptive fentanyl is more effective than placebo and reasonably safe, the results of the current study may change nursing attitude in managing turning in critically ill patients. As a consequence, pain may be decreased during this nursing procedure. © 2014 John Wiley & Sons Ltd.

  8. Mining of high utility-probability sequential patterns from uncertain databases.

    Directory of Open Access Journals (Sweden)

    Binbin Zhang

    Full Text Available High-utility sequential pattern mining (HUSPM has become an important issue in the field of data mining. Several HUSPM algorithms have been designed to mine high-utility sequential patterns (HUPSPs. They have been applied in several real-life situations such as for consumer behavior analysis and event detection in sensor networks. Nonetheless, most studies on HUSPM have focused on mining HUPSPs in precise data. But in real-life, uncertainty is an important factor as data is collected using various types of sensors that are more or less accurate. Hence, data collected in a real-life database can be annotated with existing probabilities. This paper presents a novel pattern mining framework called high utility-probability sequential pattern mining (HUPSPM for mining high utility-probability sequential patterns (HUPSPs in uncertain sequence databases. A baseline algorithm with three optional pruning strategies is presented to mine HUPSPs. Moroever, to speed up the mining process, a projection mechanism is designed to create a database projection for each processed sequence, which is smaller than the original database. Thus, the number of unpromising candidates can be greatly reduced, as well as the execution time for mining HUPSPs. Substantial experiments both on real-life and synthetic datasets show that the designed algorithm performs well in terms of runtime, number of candidates, memory usage, and scalability for different minimum utility and minimum probability thresholds.

  9. Mining of high utility-probability sequential patterns from uncertain databases.

    Science.gov (United States)

    Zhang, Binbin; Lin, Jerry Chun-Wei; Fournier-Viger, Philippe; Li, Ting

    2017-01-01

    High-utility sequential pattern mining (HUSPM) has become an important issue in the field of data mining. Several HUSPM algorithms have been designed to mine high-utility sequential patterns (HUPSPs). They have been applied in several real-life situations such as for consumer behavior analysis and event detection in sensor networks. Nonetheless, most studies on HUSPM have focused on mining HUPSPs in precise data. But in real-life, uncertainty is an important factor as data is collected using various types of sensors that are more or less accurate. Hence, data collected in a real-life database can be annotated with existing probabilities. This paper presents a novel pattern mining framework called high utility-probability sequential pattern mining (HUPSPM) for mining high utility-probability sequential patterns (HUPSPs) in uncertain sequence databases. A baseline algorithm with three optional pruning strategies is presented to mine HUPSPs. Moroever, to speed up the mining process, a projection mechanism is designed to create a database projection for each processed sequence, which is smaller than the original database. Thus, the number of unpromising candidates can be greatly reduced, as well as the execution time for mining HUPSPs. Substantial experiments both on real-life and synthetic datasets show that the designed algorithm performs well in terms of runtime, number of candidates, memory usage, and scalability for different minimum utility and minimum probability thresholds.

  10. Changes in nuclear phenotype frequencies following sequential cold shocks in Triatoma infestans (Hemiptera, Reduviidae

    Directory of Open Access Journals (Sweden)

    Silvana GP Campos

    2002-09-01

    Full Text Available The nuclear phenotypes of Malpighian tubule cells in fifth instar nymphs of Triatoma infestans, one of the most important vectors of Chagas disease, were studied following sequential shocks at 0ºC, separated by intervals of 8 h and 24 h at 30ºC, under conditions of moderate fasting and full nourishment. The insects pertained to colonies reared in the laboratory and originated from domestic specimens collected in the Brazilian states of São Paulo (north and Minas Gerais (south. Since nuclear phenotypes in this species are affected by single cold shocks, it was expected that these phenotypes could also be changed by sequential shocks. Nuclear phenotypes indicative of mechanisms of cell survival (nuclear fusion and heterochromatin decondensation and cell death (apoptosis and necrosis were observed concomitantly in all the conditions tested. Nuclear fusion and heterochromatin decondensation were not found relevant for the presumed acquisition of the cold-hardening response in T. infestans. The decreased frequency of apoptosis and necrosis following sequential cold shocks including under fasting conditions, indicated that tolerance to sequential cold shocks occurred in T. infestans of the mentioned origin.

  11. Simultaneous perceptual and response biases on sequential face attractiveness judgments.

    Science.gov (United States)

    Pegors, Teresa K; Mattar, Marcelo G; Bryan, Peter B; Epstein, Russell A

    2015-06-01

    Face attractiveness is a social characteristic that we often use to make first-pass judgments about the people around us. However, these judgments are highly influenced by our surrounding social world, and researchers still understand little about the mechanisms underlying these influences. In a series of 3 experiments, we use a novel sequential rating paradigm that enables us to measure biases in attractiveness judgments from the previous face and the previous rating. Our results reveal 2 simultaneous and opposing influences on face attractiveness judgments that arise from past experience of faces: a response bias in which attractiveness ratings shift toward a previously given rating and a stimulus bias in which attractiveness ratings shift away from the mean attractiveness of the previous face. Further, we provide evidence that the contrastive stimulus bias (but not the assimilative response bias) is strengthened by increasing the duration of the previous stimulus, suggesting an underlying perceptual mechanism. These results demonstrate that judgments of face attractiveness are influenced by information from our evaluative and perceptual history and that these influences have measurable behavioral effects over the course of just a few seconds. (c) 2015 APA, all rights reserved).

  12. Robust Sequential Circuits Design Technique for Low Voltage and High Noise Scenarios

    Directory of Open Access Journals (Sweden)

    Garcia-Leyva Lancelot

    2016-01-01

    In this paper we introduce an innovative input and output data redundancy principle for sequential block circuits, the responsible to keep the state of the system, showing its efficiency in front of other robust technique approaches. The methodology is totally different from the Von Neumann approaches, because element are not replicated N times, but instead, they check the coherence of redundant input data no allowing data propagation in case of discrepancy. This mechanism does not require voting devices.

  13. Effects of sequential feeding with low- and high-protein diets on growth performances and plasma metabolite levels in geese.

    Science.gov (United States)

    Ho, S-Y; Chen, Y-H; Yang, S-K

    2015-06-01

    This study was conducted by two trials to investigate effects of sequential feeding with low- and high-protein diets on growth traits and plasma metabolites in geese. In Trial I, the effect of sequential feeding under time-restricted feeding system was investigated. Seventy-two White Roman goslings were randomly allotted into either sequential feeding (S1) or control feeding (C1) group. All goslings were fed for 1 h at morning and at evening, respectively, from 2 to 8 weeks of age. S1 group was offered 13% CP diet at morning and 19% CP diet at evening. C1 group was offered the same diet (16% CP; mixed equally with the two diets mentioned above) at both morning and evening. Blood samples were hourly collected for 4 h after feeding at both morning and evening for the determination of the postprandial plasma levels of glucose, triacylglycerol and uric acid at the end of experiment. Results showed that BW, average daily gain (ADG), and daily feed intake (FI) were not different between groups, but the feed efficiency (FE) in S1 group was significantly higher than that in C1 group (Peffect of sequential feeding under ad libitum feeding system was investigated. Twenty-four goslings were randomly allotted into either sequential feeding (S2) or control feeding (C2) group. Diets were altered at 0600 and 1800 h, respectively, and geese were fed ad libitum from 4 to 8 weeks of age. S2 group was offered 14% CP diet at morning and 20% CP diet at evening. C2 group was supplied the same diet (mixed with the two diets according to the ratio of diets consumed by S2 group on the preceded day) at both morning and evening. Results showed that the ADG in S2 group was higher than those in C2 group (P<0.05). Summarized data from both trials showed that sequential feeding improves daily gain and FE in growing geese.

  14. Effects of patient-directed music intervention on anxiety and sedative exposure in critically ill patients receiving mechanical-ventilatory support: a randomized clinical trial

    Science.gov (United States)

    Chlan, Linda L.; Weinert, Craig R.; Heiderscheit, Annie; Tracy, Mary Fran; Skaar, Debra J.; Guttormson, Jill L.; Savik, Kay

    2013-01-01

    Context Alternatives to sedative medications are needed to reduce anxiety in mechanically ventilated patients. Music is an integrative therapy without adverse effects that may alleviate the anxiety associated with ventilatory support. Objective To test whether patient-directed, self-initiated music listening can reduce anxiety and sedative exposure during ventilatory support in critically ill patients as compared with 2 control conditions. Design, Setting, and Patients Randomized, controlled trial that enrolled 373 ICU patients from the Minneapolis-St. Paul area receiving acute mechanical-ventilatory support for respiratory failure between September 2006 and March 2011. Patients were Caucasian (86%), female (52%), with mean age 59 (SD 14), APACHE III 63 (SD 21.6), on protocol 5.7 (SD 6.4) days. Intervention Patients (1) self-initiated music listening (patient-directed music; PDM) with preferred selections tailored by a music therapist whenever desired while receiving ventilatory support, (2) self-initiated use of noise-abating headphones (HP), or (3) received usual ICU care (UC). Main Outcome Measures Daily assessments of anxiety (100-mm visual analog scale) and two aggregate measure of sedative exposure (sedation intensity and sedation frequency). Results Mixed-models analysis showed that PDM patients had decreased levels of anxiety compared with the UC group of −19.5 (p=.003). By the fifth study day anxiety was reduced by 36.5% in PDM patients. The interaction between treatment and time showed PDM significantly reduced both measures of sedative exposure. PDM reduced sedation intensity by −.18 (−.36, −.004) points per day and frequency by −.21 (−.37, −.05) points per day compared to UC (p = .05, .01 respectively). PDM reduced sedation frequency by −.18 (−.36, −.004) points per day compared to HP (p = .04). By the fifth study day, PDM patients received two fewer sedative doses (reduction of 38%) and had a reduction of 36% in sedation intensity

  15. Effects that passive cycling exercise have on muscle strength, duration of mechanical ventilation, and length of hospital stay in critically ill patients: a randomized clinical trial.

    Science.gov (United States)

    Machado, Aline Dos Santos; Pires-Neto, Ruy Camargo; Carvalho, Maurício Tatsch Ximenes; Soares, Janice Cristina; Cardoso, Dannuey Machado; Albuquerque, Isabella Martins de

    2017-01-01

    To evaluate the effects that passive cycling exercise, in combination with conventional physical therapy, have on peripheral muscle strength, duration of mechanical ventilation, and length of hospital stay in critically ill patients admitted to the ICU of a tertiary care university hospital. This was a randomized clinical trial involving 38 patients (≥ 18 years of age) on mechanical ventilation who were randomly divided into two groups: control (n = 16), receiving conventional physical therapy; and intervention (n = 22), receiving conventional physical therapy and engaging in passive cycling exercise five days per week. The mean age of the patients was 46.42 ± 16.25 years, and 23 were male. The outcomes studied were peripheral muscle strength, as measured by the Medical Research Council scale, duration of mechanical ventilation, and length of hospital stay. There was a significant increase in peripheral muscle strength (baseline vs. final) in both groups (control: 40.81 ± 7.68 vs. 45.00 ± 6.89; and intervention: 38.73 ± 11.11 vs. 47.18 ± 8.75; p fisioterapia convencional, na força muscular periférica, no tempo de ventilação mecânica e no tempo de internação hospitalar em pacientes críticos internados em UTI de um hospital universitário terciário. Ensaio clínico randomizado envolvendo 38 pacientes (idade > 18 anos) em ventilação mecânica e divididos aleatoriamente em grupo controle (n = 16), que realizou fisioterapia convencional, e grupo intervenção (n = 22) submetidos a fisioterapia convencional e exercícios passivos em cicloergômetro cinco vezes por semana. A média de idade dos pacientes foi de 46,42 ± 16,25 anos, e 23 eram homens. Os desfechos analisados foram força muscular periférica, mensurada pela escala Medical Research Council, tempo de ventilação mecânica e tempo de internação hospitalar. Houve um aumento significativo da força muscular periférica (basal vs. final) tanto no grupo controle (40,81 ± 7,68 vs. 45,00 ± 6

  16. The impact of comorbid body dysmorphic disorder on the response to sequential pharmacological trials for obsessive-compulsive disorder.

    Science.gov (United States)

    Diniz, Juliana B; Costa, Daniel Lc; Cassab, Raony Cc; Pereira, Carlos Ab; Miguel, Euripedes C; Shavitt, Roseli G

    2014-06-01

    Our aim was to investigate the impact of comorbid body dysmorphic disorder (BDD) on the response to sequential pharmacological trials in adult obsessive-compulsive disorder (OCD) patients. The sequential trial initially involved fluoxetine monotherapy followed by one of three randomized, add-on strategies: placebo, clomipramine or quetiapine. We included 138 patients in the initial phase of fluoxetine, up to 80 mg or the maximum tolerated dosage, for 12 weeks. We invited 70 non-responders to participate in the add-on trial; as 54 accepted, we allocated 18 to each treatment group and followed them for an additional 12 weeks. To evaluate the combined effects of sex, age, age at onset, initial severity, type of augmentation and BDD on the response to sequential treatments, we constructed a model using generalized estimating equations (GEE). Of the 39 patients who completed the study (OCD-BDD, n = 13; OCD-non-BDD, n = 26), the OCD-BDD patients were less likely to be classified as responders than the OCD-non-BDD patients (Pearson Chi-Square = 4.4; p = 0.036). In the GEE model, BDD was not significantly associated with a worse response to sequential treatments (z-robust = 1.77; p = 0.07). The predictive potential of BDD regarding sequential treatment strategies for OCD did not survive when the analyses were controlled for other clinical characteristics. © The Author(s) 2013.

  17. The efficacy of sequential therapy in eradication of Helicobacter ...

    African Journals Online (AJOL)

    And 40 patients received standard triple therapy for 2 weeks, 40 patients received bismuth containing quadruple therapy for 2 weeks, 40 patients received 5 + 5 clarithromycin-based sequential therapy, and 40 patients received 7 + 7 clarithromycin-based sequential therapy. H. pylori eradication was assessed by C 14 urea ...

  18. The sequential price of anarchy for atomic congestion games

    NARCIS (Netherlands)

    de Jong, Jasper; Uetz, Marc Jochen; Liu, Tie-Yan; Qi, Qi; Ye, Yinyu

    2014-01-01

    In situations without central coordination, the price of anarchy relates the quality of any Nash equilibrium to the quality of a global optimum. Instead of assuming that all players choose their actions simultaneously, we consider games where players choose their actions sequentially. The sequential

  19. Derivation of sequential, real-time, process-control programs

    Science.gov (United States)

    Marzullo, Keith; Schneider, Fred B.; Budhiraja, Navin

    1991-01-01

    The use of weakest-precondition predicate transformers in the derivation of sequential, process-control software is discussed. Only one extension to Dijkstra's calculus for deriving ordinary sequential programs was found to be necessary: function-valued auxiliary variables. These auxiliary variables are needed for reasoning about states of a physical process that exists during program transitions.

  20. The Clinical effectiveness of sequential treatment of skeletal class III ...

    African Journals Online (AJOL)

    Aim: To assess the dentofacial changes induced by the sequential treatment in the skeletal class III malocclusion with maxillary retrognathism. Study design: Controlled clinical trial assessing the effectiveness of sequential treatment of skeletal class III malocclusion. Materials and Methods: The treated group consisted of 30 ...

  1. Revenue Prediction in Budget-constrained Sequential Auctions with Complementarities

    NARCIS (Netherlands)

    S. Verwer (Sicco); Y. Zhang (Yingqian)

    2011-01-01

    textabstractWhen multiple items are auctioned sequentially, the ordering of auctions plays an important role in the total revenue collected by the auctioneer. This is true especially with budget constrained bidders and the presence of complementarities among items. In such sequential auction

  2. Sequential therapy for Helicobacter pylori eradication: a critical review.

    Science.gov (United States)

    Gisbert, Javier P; Calvet, Xavier; O'Connor, Anthony; Mégraud, Francis; O'Morain, Colm A

    2010-01-01

    Alternative treatment regimens for standard triple therapy are urgently needed. To critically review the evidence on the role of "sequential" regimen for the treatment of Helicobacter pylori infection. Bibliographical searches were performed in MEDLINE and international congresses. Several pooled-data analyses and meta-analyses have demonstrated that sequential regimen is more effective than standard triple therapy. Sequential therapy is not affected by bacterial (CagA status, infection density) and host factors (underlying disease, smoking). Clarithromycin resistance seems to be the only factor reducing their efficacy. However, even in these patients, an acceptable >75% eradication rate can be achieved. Unfortunately, almost all the studies have been performed in Italy. Whether it is necessary to provide the drugs sequentially or if the 4 components of sequential therapy can be given concurrently is unclear. Nonbismuth quadruple therapy seems to be an effective and safe alternative to triple therapy and is less complex than sequential therapy. Sequential therapy is a novel promising treatment approach that deserves consideration as a treatment strategy for H. pylori infection. However, further robust assessment across a much broader range of patients is required before sequential therapy could supplant existing treatment regimens and be generally recommended in clinical practice.

  3. Accounting for Heterogeneous Returns in Sequential Schooling Decisions

    NARCIS (Netherlands)

    Zamarro, G.

    2006-01-01

    This paper presents a method for estimating returns to schooling that takes into account that returns may be heterogeneous among agents and that educational decisions are made sequentially.A sequential decision model is interesting because it explicitly considers that the level of education of each

  4. Applications of Bayesian decision theory to sequential mastery testing

    NARCIS (Netherlands)

    Vos, Hendrik J.

    1999-01-01

    The purpose of this paper is to formulate optimal sequential rules for mastery tests. The framework for the approach is derived from Bayesian sequential decision theory. Both a threshold and linear loss structure are considered. The binomial probability distribution is adopted as the psychometric

  5. Adaptive Learning in Extensive Form Games and Sequential Equilibrium

    DEFF Research Database (Denmark)

    Groes, Ebbe; Jacobsen, Hans Jørgen; Sloth, Birgitte

    1999-01-01

    This paper studies adaptive learning in extensive form games and provides conditions for convergence points of adaptive learning to be sequential equilibria. Precisely, we present a set of conditions on learning sequences such that an assessment is a sequential equilibrium if and only...... if there is a learning sequence fulfilling the conditions, which leads to the assessment...

  6. Induction of simultaneous and sequential malolactic fermentation in durian wine.

    Science.gov (United States)

    Taniasuri, Fransisca; Lee, Pin-Rou; Liu, Shao-Quan

    2016-08-02

    This study represented for the first time the impact of malolactic fermentation (MLF) induced by Oenococcus oeni and its inoculation strategies (simultaneous vs. sequential) on the fermentation performance as well as aroma compound profile of durian wine. There was no negative impact of simultaneous inoculation of O. oeni and Saccharomyces cerevisiae on the growth and fermentation kinetics of S. cerevisiae as compared to sequential fermentation. Simultaneous MLF did not lead to an excessive increase in volatile acidity as compared to sequential MLF. The kinetic changes of organic acids (i.e. malic, lactic, succinic, acetic and α-ketoglutaric acids) varied with simultaneous and sequential MLF relative to yeast alone. MLF, regardless of inoculation mode, resulted in higher production of fermentation-derived volatiles as compared to control (alcoholic fermentation only), including esters, volatile fatty acids, and terpenes, except for higher alcohols. Most indigenous volatile sulphur compounds in durian were decreased to trace levels with little differences among the control, simultaneous and sequential MLF. Among the different wines, the wine with simultaneous MLF had higher concentrations of terpenes and acetate esters while sequential MLF had increased concentrations of medium- and long-chain ethyl esters. Relative to alcoholic fermentation only, both simultaneous and sequential MLF reduced acetaldehyde substantially with sequential MLF being more effective. These findings illustrate that MLF is an effective and novel way of modulating the volatile and aroma compound profile of durian wine. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Sequential Dependencies in Categorical Judgments of Radiographic Images

    Science.gov (United States)

    Beckstead, Jason W.; Boutis, Kathy; Pecaric, Martin; Pusic, Martin V.

    2017-01-01

    Sequential context effects, the psychological interactions occurring between the events of successive trials when a sequence of similar stimuli are judged, have interested psychologists for decades. It has been well established that individuals exhibit sequential context effects in psychophysical experiments involving unidimensional stimuli.…

  8. Development of decision making: sequential versus integrative rules

    NARCIS (Netherlands)

    Jansen, B.R.J.; van Duijvenvoorde, A.C.K.; Huizenga, H.M.

    2012-01-01

    Decisions can be made by applying a variety of decision-making rules-sequential rules in which decisions are based on a sequential evaluation of choice dimensions and the integrative normative rule in which decisions are based on an integration of choice dimensions. In this study, we investigated

  9. Short-term effects of kinesio taping versus cervical thrust manipulation in patients with mechanical neck pain: a randomized clinical trial.

    Science.gov (United States)

    Saavedra-Hernández, Manuel; Castro-Sánchez, Adelaida M; Arroyo-Morales, Manuel; Cleland, Joshua A; Lara-Palomo, Inmaculada C; Fernández-de-Las-Peñas, César

    2012-08-01

    Randomized clinical trial. To compare the effectiveness of cervical spine thrust manipulation to that of Kinesio Taping applied to the neck in individuals with mechanical neck pain, using self-reported pain and disability and cervical range of motion as measures. The effectiveness of cervical manipulation has received considerable attention in the literature. However, because some patients cannot tolerate cervical thrust manipulation, alternative therapeutic options should be investigated. Eighty patients (36 women) were randomly assigned to 1 of 2 groups: the manipulation group, which received 2 cervical thrust manipulations, and the tape group, which received Kinesio Taping applied to the neck. Neck pain (11-point numeric pain rating scale), disability (Neck Disability Index), and cervical-range-of-motion data were collected at baseline and 1 week after the intervention by an assessor blinded to the treatment allocation of the patients. Mixed-model analyses of variance were used to examine the effects of the treatment on each outcome variable, with group as the between-subjects variable and time as the within-subjects variable. The primary analysis was the group-by-time interaction. No significant group-by-time interactions were found for pain (F = 1.892, P = .447) or disability (F = 0.115, P = .736). The group-by-time interaction was statistically significant for right (F = 7.317, P = .008) and left (F = 9.525, P = .003) cervical rotation range of motion, with the patients who received the cervical thrust manipulation having experienced greater improvement in cervical rotation than those treated with Kinesio Tape (PKinesio Taping exhibited similar reductions in neck pain intensity and disability and similar changes in active cervical range of motion, except for rotation. Changes in neck pain surpassed the minimal clinically important difference, whereas changes in disability did not. Changes in cervical range of motion were small and not clinically meaningful

  10. A preliminary randomized trial of the mechanical insufflator-exsufflator versus breath-stacking technique in patients with amyotrophic lateral sclerosis.

    Science.gov (United States)

    Rafiq, Muhammad K; Bradburn, Michael; Proctor, Alison R; Billings, Catherine G; Bianchi, Stephen; McDermott, Christopher J; Shaw, Pamela J

    2015-01-01

    A major problem faced by patients with amyotrophic lateral sclerosis (ALS) in respiratory failure is the inability to cough effectively. Forty eligible ALS patients were randomized to the breath-stacking technique using a lung volume recruitment bag (n = 21) or mechanical insufflator-exsufflator MI-E (n = 19) and followed up at three-monthly intervals for at least 12 months or until death. Results showed that there were 13 episodes of chest infection in the breath-stacking group and 19 episodes in the MI-E group (p = 0.92), requiring 90 and 95 days of antibiotics, respectively (p = 0.34). The mean duration of symptoms per chest infection was 6.9 days in the breath-stacking group and 3.9 days in MI-E group (p = 0.16). There were six episodes of hospitalization in each group (p = 0.64). The chance of hospitalization, in the event of a chest infection, was 0.46 in the breath-stacking group and 0.31 in MI-E group (p = 0.47). Median survival in the breath-stacking group was 535 days and 266 days in the MI-E group (p = 0.34). The QoL was maintained above 75% of baseline for a median of 329 days in the breath-stacking group and 205 days in the MI-E group (p = 0.41). In conclusion, lack of statistically significant differences due to sub-optimal power and confounders precludes a definitive conclusion with respect to the relative efficacy of one cough augmentation technique over the other. This study however, provides useful lessons and informative data, needed to strengthen the power calculation, inclusion criteria and randomization factors for a large scale definitive trial. Until such a definitive trial can be undertaken, we recommend the breath-stacking technique as a low-cost, first-line intervention for volume recruitment and cough augmentation in patients with ALS who meet the criteria for intervention with non-invasive ventilation.

  11. Magnetic resonance imaging zygapophyseal joint space changes (gapping) in low back pain patients following spinal manipulation and side-posture positioning: a randomized controlled mechanisms trial with blinding.

    Science.gov (United States)

    Cramer, Gregory D; Cambron, Jerrilyn; Cantu, Joe A; Dexheimer, Jennifer M; Pocius, Judith D; Gregerson, Douglas; Fergus, Michael; McKinnis, Ray; Grieve, Thomas J

    2013-05-01

    The purpose of this study was to quantify lumbar zygapophyseal (Z) joint space separation (gapping) in low back pain (LBP) subjects after spinal manipulative therapy (SMT) or side-posture positioning (SPP). This was a controlled mechanisms trial with randomization and blinding. Acute LBP subjects (N = 112; four n = 28 magnetic resonance imaging [MRI] protocol groups) had 2 MRI appointments (initial enrollment and after 2 weeks of chiropractic treatment, receiving 2 MRI scans of the L4/L5 and L5/S1 Z joints at each MRI appointment. After the first MRI scan of each appointment, subjects were randomized (initial enrollment appointment) or assigned (after 2 weeks of chiropractic treatment appointment) into SPP (nonmanipulation), SMT (manipulation), or control MRI protocol groups. After SPP or SMT, a second MRI was taken. The central anterior-posterior joint space was measured. Difference between most painful side anterior-posterior measurements taken postintervention and preintervention was the Z joint "gapping difference." Gapping differences were compared (analysis of variance) among protocol groups. Secondary measures of pain (visual analog scale, verbal numeric pain rating scale) and function (Bournemouth questionnaire) were assessed. Gapping differences were significant at the first (adjusted, P = .009; SPP, 0.66 ± 0.48 mm; SMT, 0.23 ± 0.86; control, 0.18 ± 0.71) and second (adjusted, P = .0005; SPP, 0.65 ± 0.92 mm; SMT, 0.89 ± 0.71; control, 0.35 ± 0.32) MRI appointments. Verbal numeric pain rating scale differences were significant at first MRI appointment (P = .04) with SMT showing the greatest improvement. Visual analog scale and Bournemouth questionnaire improved after 2 weeks of care in all groups (both P < .0001). Side-posture positioning showed greatest gapping at baseline. After 2 weeks, SMT resulted in greatest gapping. Side-posture positioning appeared to have additive therapeutic benefit to SMT. Copyright © 2013 National University of Health

  12. Effect of driving pressure on mortality in ARDS patients during lung protective mechanical ventilation in two randomized controlled trials.

    Science.gov (United States)

    Guérin, Claude; Papazian, Laurent; Reignier, Jean; Ayzac, Louis; Loundou, Anderson; Forel, Jean-Marie

    2016-11-29

    Driving pressure (ΔPrs) across the respiratory system is suggested as the strongest predictor of hospital mortality in patients with acute respiratory distress syndrome (ARDS). We wonder whether this result is related to the range of tidal volume (VT). Therefore, we investigated ΔPrs in two trials in which strict lung-protective mechanical ventilation was applied in ARDS. Our working hypothesis was that ΔPrs is a risk factor for mortality just like compliance (Crs) or plateau pressure (Pplat,rs) of the respiratory system. We performed secondary analysis of data from 787 ARDS patients enrolled in two independent randomized controlled trials evaluating distinct adjunctive techniques while they were ventilated as in the low VT arm of the ARDSnet trial. For this study, we used VT, positive end-expiratory pressure (PEEP), Pplat,rs, Crs, ΔPrs, and respiratory rate recorded 24 hours after randomization, and compared them between survivors and nonsurvivors at day 90. Patients were followed for 90 days after inclusion. Cox proportional hazard modeling was used for mortality at day 90. If colinearity between ΔPrs, Crs, and Pplat,rs was verified, specific Cox models were used for each of them. Both trials enrolled 805 patients of whom 787 had day-1 data available, and 533 of these survived. In the univariate analysis, ΔPrs averaged 13.7 ± 3.7 and 12.8 ± 3.7 cmH2O (P = 0.002) in nonsurvivors and survivors, respectively. Colinearity between ΔPrs, Crs and Pplat,rs, which was expected as these variables are mathematically coupled, was statistically significant. Hazard ratios from the Cox models for day-90 mortality were 1.05 (1.02-1.08) (P = 0.005), 1.05 (1.01-1.08) (P = 0.008) and 0.985 (0.972-0.985) (P = 0.029) for ΔPrs, Pplat,rs and Crs, respectively. PEEP and VT were not associated with death in any model. When ventilating patients with low VT, ΔPrs is a risk factor for death in ARDS patients, as is Pplat,rs or Crs. As our data originated

  13. A Comparison of the Effects of Stabilization Exercises Plus Manual Therapy to Those of Stabilization Exercises Alone in Patients With Nonspecific Mechanical Neck Pain: A Randomized Clinical Trial.

    Science.gov (United States)

    Celenay, Seyda Toprak; Akbayrak, Turkan; Kaya, Derya Ozer

    2016-02-01

    Randomized clinical trial. Little is known about the efficacy of providing manual therapy in addition to cervical and scapulothoracic stabilization exercises in people with mechanical neck pain (MNP). Objectives To compare the effects of stabilization exercises plus manual therapy to those of stabilization exercises alone on disability, pain, range of motion (ROM), and quality of life in patients with MNP. One hundred two patients with MNP (18-65 years of age) were recruited and randomly allocated into 2 groups: stabilization exercise without (n = 51) and with (n = 51) manual therapy. The program was carried out 3 days per week for 4 weeks. The Neck Disability Index, visual analog pain scale, digital algometry of pressure pain threshold, goniometric measurements, and Medical Outcomes Study 36-Item Short-Form Health Survey were used to assess participants at baseline and after 4 weeks. Improvements in Neck Disability Index score, night pain, rotation ROM, and the Medical Outcomes Study 36-Item Short-Form Health Survey score were greater in the group that received stabilization exercise with manual therapy compared to the group that only received stabilization exercise. Between-group differences (95% confidence interval) were 2.2 (0.1, 4.3) points for the Neck Disability Index, 1.1 (0.0, 2.3) cm for pain at night measured on the visual analog scale, -4.3° (-8.1°, -0.5°) and -5.0° (-8.2°, -1.7°) for right and left rotation ROM, respectively, and -2.9 (-5.4, -0.4) points and -3.1 (-6.2, 0.0) points for the Medical Outcomes Study 36-Item Short-Form Health Survey physical and mental components, respectively. Changes in resting and activity pain, pressure pain threshold, and cervical extension or lateral flexion ROM did not differ significantly between the groups. Pressure pain threshold increased only in those who received stabilization exercise with manual therapy (Pmanual therapy may be superior to stabilization exercises alone for improving disability, pain

  14. Effect of Mo on the phase stability and elastic mechanical properties of Ti-Mo random alloys from ab initio calculations

    Science.gov (United States)

    Cao, Peiyu; Tian, Fuyang; Wang, Yandong

    2017-11-01

    Ti-Mo alloys are promising materials for shape memory alloys and biomedical materials. Whereas, the appearance of metastable ω phase can cause embrittlement and destroy the shape memory effect. In order to avoid the ω phase, the effect of Mo on the temperature dependent lattice parameters, phase stability and elastic mechanical properties of β, α, and ω Ti1-x Mo x (x  =  0-2.0) random alloys was systematically investigated by using the exact muffin-tin orbitals method in combination with the coherent potential approximation. The theoretical predictions for the lattice parameters are in good agreement with the available experiments. Results show that β Ti0.96Mo0.04 can almost transform to ω phase without lattice deformation and volume change, which suggests that the athermal ω phase is easier to precipitate and grow near 4 at.% Mo content in the β Ti1-x Mo x alloys. The critical content of Mo for the competed stabilization of β phase at T  =  300 K is ~11.2 at.%. Its valence electron concentration of 4.224 is viewed as a necessary criterion for the competed phase stability. The calculations of formation energy are used to explain successfully why the partitioning of Mo can be found in Ti0.91Mo0.09 alloy after annealing. Through the analysis of formation energy, both Mo addition and increasing temperature can stabilize the β phase. The calculated Cauchy pressure, Pugh’s ratio, Poisson ratio, and Young’s modulus suggests that ω phase is intrinsically brittle and has large Young’s modulus compared with β and α phases.

  15. Comparing effects between music intervention and aromatherapy on anxiety of patients undergoing mechanical ventilation in the intensive care unit: a randomized controlled trial.

    Science.gov (United States)

    Lee, Chiu-Hsiang; Lai, Chiung-Ling; Sung, Yi-Hui; Lai, Mei Yu; Lin, Chung-Ying; Lin, Long-Yau

    2017-07-01

    Using patient-reported outcomes and physiological indicators to test the effects of music intervention and aromatherapy on reducing anxiety for intensive care unit (ICU) patients undergoing mechanical ventilation. Patients with ICU admission duration >24 h were randomly assigned to a Music intervention group (n = 41), Aromatherapy group (n = 47), or Control group (rest only; n = 44). Each patient in the Music group listened to music; each patient in the Aromatherapy group received lavender essential oil massage on his/her back for 5 min; each patient in the Control group wore noise-canceling headphones. Anxiety was measured using the Chinese version of the Stage-Trait Anxiety Inventory (C-STAI) and the Visual Analogue Scale for Anxiety (VAS-A) at baseline, post-test, and 30-min follow-up. Heart rate, breathing rate, and blood pressure were measured every 10 min from baseline to the 30-min follow-up. The Music group had significantly better post-test VAS-A and C-STAI scores, and had lower heart rate and blood pressure than the Control group. The Aromatherapy group had significantly better VAS-A score and lower heart rate than the Control group. The 30-min follow-up showed that both Music and Aromatherapy groups had lower heart rate and blood pressure than the Control group. Music and aromatherapy interventions were both effective for ICU patients. The effects of music intervention were greater than that of aromatherapy; both interventions maintained the effects for at least 30 min.

  16. The effects of isolated ankle strengthening and functional balance training on strength, running mechanics, postural control and injury prevention in novice runners: design of a randomized controlled trial.

    Science.gov (United States)

    Baltich, Jennifer; Emery, Carolyn A; Stefanyshyn, Darren; Nigg, Benno M

    2014-12-04

    Risk factors have been proposed for running injuries including (a) reduced muscular strength, (b) excessive joint movements and (c) excessive joint moments in the frontal and transverse planes. To date, many running injury prevention programs have focused on a "top down" approach to strengthen the hip musculature in the attempt to reduce movements and moments at the hip, knee, and/or ankle joints. However, running mechanics did not change when hip muscle strength increased. It could be speculated that emphasis should be placed on increasing the strength of the ankle joint for a "ground up" approach. Strengthening of the large and small muscles crossing the ankle joint is assumed to change the force distribution for these muscles and to increase the use of smaller muscles. This would be associated with a reduction of joint and insertion forces, which could have a beneficial effect on injury prevention. However, training of the ankle joint as an injury prevention strategy has not been studied. Ankle strengthening techniques include isolated strengthening or movement-related strengthening such as functional balance training. There is little knowledge about the efficacy of such training programs on strength alteration, gait or injury reduction. Novice runners will be randomly assigned to one of three groups: an isolated ankle strengthening group (strength, n = 40), a functional balance training group (balance, n = 40) or an activity-matched control group (control, n = 40). Isokinetic strength will be measured using a Biodex System 3 dynamometer. Running kinematics and kinetics will be assessed using 3D motion analysis and a force platform. Postural control will be assessed by quantifying the magnitude and temporal structure of the center of pressure trace during single leg stance on a force platform. The change pre- and post-training in isokinetic strength, running mechanics, and postural control variables will be compared following the interventions

  17. Effects of eye movement desensitization and reprocessing (EMDR) on non-specific chronic back pain: a randomized controlled trial with additional exploration of the underlying mechanisms.

    Science.gov (United States)

    Tesarz, Jonas; Gerhardt, Andreas; Leisner, Sabine; Janke, Susanne; Hartmann, Mechthild; Seidler, Günther H; Eich, Wolfgang

    2013-08-30

    Non-specific chronic back pain (CBP) is often accompanied by psychological trauma, but treatment for this associated condition is often insufficient.Nevertheless, despite the common co-occurrence of pain and psychological trauma, a specific trauma-focused approach for treating CBP has been neglected to date. Accordingly, eye movement desensitization and reprocessing (EMDR), originally developed as a treatment approach for posttraumatic stress disorders, is a promising approach for treating CBP in patients who have experienced psychological trauma.Thus, the aim of this study is to determine whether a standardized, short-term EMDR intervention added to treatment as usual (TAU) reduces pain intensity in CBP patients with psychological trauma vs. TAU alone. The study will recruit 40 non-specific CBP patients who have experienced psychological trauma. After a baseline assessment, the patients will be randomized to either an intervention group (n = 20) or a control group (n = 20). Individuals in the EMDR group will receive ten 90-minute sessions of EMDR fortnightly in addition to TAU. The control group will receive TAU alone. The post-treatment assessments will take place two weeks after the last EMDR session and six months later.The primary outcome will be the change in the intensity of CBP within the last four weeks (numeric rating scale 0-10) from the pre-treatment assessment to the post-treatment assessment two weeks after the completion of treatment.In addition, the patients will undergo a thorough assessment of the change in the experience of pain, disability, trauma-associated distress, mental co-morbidities, resilience, and quality of life to explore distinct treatment effects. To explore the mechanisms of action that are involved, changes in pain perception and pain processing (quantitative sensory testing, conditioned pain modulation) will also be assessed.The statistical analysis of the primary outcome will be performed on an intention-to-treat basis

  18. Sequential Immune Responses: The Weapons of Immunity.

    Science.gov (United States)

    Mills, Charles D; Ley, Klaus; Buchmann, Kurt; Canton, Johnathan

    2015-01-01

    Sequential immune responses (SIR) is a new model that describes what 'immunity' means in higher animals. Existing models, such as self/nonself discrimination or danger, focus on how immune responses are initiated. However, initiation is not protection. SIR describes the actual immune responses that provide protection. SIR resulted from a comprehensive analysis of the evolution of immune systems that revealed that several very different types of host innate responses occur (and at different tempos) which together provide host protection. SIR1 uses rapidly activated enzymes like the NADPH oxidases and is present in all animal cells. SIR2 is mediated by the first 'immune' cells: macrophage-like cells. SIR3 evolved in animals like invertebrates and provides enhanced protection through advanced macrophage recognition and killing of pathogens and through other innate immune cells such as neutrophils. Finally, in vertebrates, macrophages developed SIR4: the ability to present antigens to T cells. Though much slower than SIR1-3, adaptive responses provide a unique new protection for higher vertebrates. Importantly, newer SIR responses were added on top of older, evolutionarily conserved functions to provide 'layers' of host protection. SIR transcends existing models by elucidating the different weapons of immunity that provide host protection in higher animals. © 2015 S. Karger AG, Basel.

  19. Sequential detection of learning in cognitive diagnosis.

    Science.gov (United States)

    Ye, Sangbeak; Fellouris, Georgios; Culpepper, Steven; Douglas, Jeff

    2016-05-01

    In order to look more closely at the many particular skills examinees utilize to answer items, cognitive diagnosis models have received much attention, and perhaps are preferable to item response models that ordinarily involve just one or a few broadly defined skills, when the objective is to hasten learning. If these fine-grained skills can be identified, a sharpened focus on learning and remediation can be achieved. The focus here is on how to detect when learning has taken place for a particular attribute and efficiently guide a student through a sequence of items to ultimately attain mastery of all attributes while administering as few items as possible. This can be seen as a problem in sequential change-point detection for which there is a long history and a well-developed literature. Though some ad hoc rules for determining learning may be used, such as stopping after M consecutive items have been successfully answered, more efficient methods that are optimal under various conditions are available. The CUSUM, Shiryaev-Roberts and Shiryaev procedures can dramatically reduce the time required to detect learning while maintaining rigorous Type I error control, and they are studied in this context through simulation. Future directions for modelling and detection of learning are discussed. © 2016 The British Psychological Society.

  20. Social Influences in Sequential Decision Making.

    Science.gov (United States)

    Schöbel, Markus; Rieskamp, Jörg; Huber, Rafael

    2016-01-01

    People often make decisions in a social environment. The present work examines social influence on people's decisions in a sequential decision-making situation. In the first experimental study, we implemented an information cascade paradigm, illustrating that people infer information from decisions of others and use this information to make their own decisions. We followed a cognitive modeling approach to elicit the weight people give to social as compared to private individual information. The proposed social influence model shows that participants overweight their own private information relative to social information, contrary to the normative Bayesian account. In our second study, we embedded the abstract decision problem of Study 1 in a medical decision-making problem. We examined whether in a medical situation people also take others' authority into account in addition to the information that their decisions convey. The social influence model illustrates that people weight social information differentially according to the authority of other decision makers. The influence of authority was strongest when an authority's decision contrasted with private information. Both studies illustrate how the social environment provides sources of information that people integrate differently for their decisions.

  1. Social Influences in Sequential Decision Making.

    Directory of Open Access Journals (Sweden)

    Markus Schöbel

    Full Text Available People often make decisions in a social environment. The present work examines social influence on people's decisions in a sequential decision-making situation. In the first experimental study, we implemented an information cascade paradigm, illustrating that people infer information from decisions of others and use this information to make their own decisions. We followed a cognitive modeling approach to elicit the weight people give to social as compared to private individual information. The proposed social influence model shows that participants overweight their own private information relative to social information, contrary to the normative Bayesian account. In our second study, we embedded the abstract decision problem of Study 1 in a medical decision-making problem. We examined whether in a medical situation people also take others' authority into account in addition to the information that their decisions convey. The social influence model illustrates that people weight social information differentially according to the authority of other decision makers. The influence of authority was strongest when an authority's decision contrasted with private information. Both studies illustrate how the social environment provides sources of information that people integrate differently for their decisions.

  2. An Improved Sequential Smoothing Particle Filtering Method

    Directory of Open Access Journals (Sweden)

    Cao Shijie

    2017-01-01

    Full Text Available In order to cope with the challenges of non-cooperative targets such as stealth targets to modern radar, especially when traditional threshold detection and tracking methods can hardly detect fast-moving stealth targets, technological innovation has long been required. In this paper we have proposed a new algorithm which can reduce computational cost and improve tracking accuracy. Firstly, the number of particles in the traditional particle filter is reduced and a small number of sampling points are derived from the possible distribution of the target to be tracked, each given a proper weight. Then, the transformed sampling points are sequentially smoothed. And finally, the target positions are estimated. The simulation results show that the proposed algorithm is more accurate than the traditional particle filter algorithm and has lower computational complexity. In the case when SNR is between 0dB to 15dB, a total of 100 Monte Carlo simulations are carried out, obtaining a high detection probability. The detection probability of the improved algorithm is higher than that of the existing particle filter at 7dB. Also, the computational cost is lower than the existing particle filter algorithm.

  3. Sequential Steps of CRAC Channel Activation

    Directory of Open Access Journals (Sweden)

    Raz Palty

    2017-05-01

    Full Text Available Interaction between the endoplasmic reticulum protein STIM1 and the plasma membrane channel ORAI1 generates calcium signals that are central for diverse cellular functions. How STIM1 binds and activates ORAI1 remains poorly understood. Using electrophysiological, optical, and biochemical techniques, we examined the effects of mutations in the STIM1-ORAI1 activating region (SOAR of STIM1. We find that SOAR mutants that are deficient in binding to resting ORAI1 channels are able to bind to and boost activation of partially activated ORAI1 channels. We further show that the STIM1 binding regions on ORAI1 undergo structural rearrangement during channel activation. The results suggest that activation of ORAI1 by SOAR occurs in multiple steps. In the first step, SOAR binds to ORAI1, partially activates the channel, and induces a rearrangement in the SOAR-binding site of ORAI1. That rearrangement of ORAI1 then permits sequential steps of SOAR binding, via distinct molecular interactions, to fully activate the channel.

  4. Sequential stages of human T lymphocyte differentiation

    Science.gov (United States)

    Touraine, Jean-Louis; Hadden, John W.; Good, Robert A.

    1977-01-01

    Induction of thymus-dependent lymphocyte (T cell) differentiation was performed in vitro with thymic factors as inducers. T cell precursors from human bone marrow first expressed surface differentiation antigens and then acquired the capacity to form rosettes with sheep erythrocytes. The latter marker could not be induced when cells with differentiation antigens had been eliminated. The proliferative responses to phytomitogens or to allogeneic stimuli appeared to be characteristics of later stages in differentiation that also can be induced or amplified by in vitro incubation of marrow cells or thymocytes with thymic factors. When phytomitogen-responsive cells from peripheral blood were inactivated in vitro, the allogeneic response was enhanced. Although these responses are acquired almost concomitantly, they are therefore envisioned to be characteristics of separate T cell subsets. After immunological reconstitution of patients, the T cell development in vivo involves a succession of differentiation events similar to that described above. Our experiments with mice, using similar methods, have also shown that graft-versus-host inducing capacity is a function of a cell population distinct from that which yields a proliferative response to in vitro stimulation by phytohemagglutinin. These results support our model of sequential differentiation of human prothymocytes into various subsets of mature T cells. Images PMID:302943

  5. Sequential Immune Responses: The Weapons of Immunity

    Science.gov (United States)

    Mills, Charles D.; Ley, Klaus; Buchmann, Kurt; Canton, Johnathan

    2016-01-01

    Sequential immune responses (SIR) is a new model that describes what ‘immunity’ means in higher animals. Existing models, such as self/nonself discrimination or danger, focus on how immune responses are initiated. However, initiation is not protection. SIR describes the actual immune responses that provide protection. SIR resulted from a comprehensive analysis of the evolution of immune systems that revealed that several very different types of host innate responses occur (and at different tempos) which together provide host protection. SIR1 uses rapidly activated enzymes like the NADPH oxidases and is present in all animal cells. SIR2 is mediated by the first ‘immune’ cells: macrophage-like cells. SIR3 evolved in animals like invertebrates and provides enhanced protection through advanced macrophage recognition and killing of pathogens and through other innate immune cells such as neutrophils. Finally, in vertebrates, macrophages developed SIR4: the ability to present antigens to T cells. Though much slower than SIR1–3, adaptive responses provide a unique new protection for higher vertebrates. Importantly, newer SIR responses were added on top of older, evolutionarily conserved functions to provide ‘layers’ of host protection. SIR transcends existing models by elucidating the different weapons of immunity that provide host protection in higher animals. PMID:25871013

  6. DNA-nanostructure-assembly by sequential spotting

    Directory of Open Access Journals (Sweden)

    Breitenstein Michael

    2011-11-01

    Full Text Available Abstract Background The ability to create nanostructures with biomolecules is one of the key elements in nanobiotechnology. One of the problems is the expensive and mostly custom made equipment which is needed for their development. We intended to reduce material costs and aimed at miniaturization of the necessary tools that are essential for nanofabrication. Thus we combined the capabilities of molecular ink lithography with DNA-self-assembling capabilities to arrange DNA in an independent array which allows addressing molecules in nanoscale dimensions. Results For the construction of DNA based nanostructures a method is presented that allows an arrangement of DNA strands in such a way that they can form a grid that only depends on the spotted pattern of the anchor molecules. An atomic force microscope (AFM has been used for molecular ink lithography to generate small spots. The sequential spotting process allows the immobilization of several different functional biomolecules with a single AFM-tip. This grid which delivers specific addresses for the prepared DNA-strand serves as a two-dimensional anchor to arrange the sequence according to the pattern. Once the DNA-nanoarray has been formed, it can be functionalized by PNA (peptide nucleic acid to incorporate advanced structures. Conclusions The production of DNA-nanoarrays is a promising task for nanobiotechnology. The described method allows convenient and low cost preparation of nanoarrays. PNA can be used for complex functionalization purposes as well as a structural element.

  7. Preceding movement effects on sequential aiming.

    Science.gov (United States)

    Cheng, Darian T; De Grosbois, John; Smirl, Jonathan; Heath, Matthew; Binsted, Gordon

    2011-11-01

    In this study, two experiments were devised to examine the control strategy used by individuals when performing sequential aiming movements. Of particular interest was the aiming behavior displayed when task difficulty was changed midway through a sequence of movements. In Experiment 1, target size was manipulated, as the targets were made either larger or smaller, between the 8th and 12th movement of the sequence. In Experiment 2, the amplitude between the two targets was similarly changed while the target size remained constant. Results revealed that in Experiment 1, individuals took two movements following the perturbation to target size, to re-tune their movement times in order to correspond with the new task difficulty. Conversely for Experiment 2, movement time changed immediately and in correspondence with the new target amplitude. These findings demonstrate that participants can use information from the preceding movement to prepare and guide subsequent movements--but only when target size is changed. When response amplitude changes mid-sequence, it seems individuals rely more on immediate, target-derived information. Therefore, counter to some current accounts of visual movement control, it appears that memory representations of the preceding movement can guide subsequent movements; however, this information appears selectively accessed in a context-dependent fashion.

  8. The Origin of Sequential Chromospheric Brightenings

    Science.gov (United States)

    Kirk, M. S.; Balasubramaniam, K. S.; Jackiewicz, J.; Gilbert, H. R.

    2017-01-01

    Sequential chromospheric brightenings (SCBs) are often observed in the immediate vicinity of erupting flares and are associated with coronal mass ejections. Since their initial discovery in 2005, there have been several subsequent investigations of SCBs. These studies have used differing detection and analysis techniques, making it difficult to compare results between studies. This work employs the automated detection algorithm of Kirk et al. (Solar Phys. 283, 97, 2013) to extract the physical characteristics of SCBs in 11 flares of varying size and intensity. We demonstrate that the magnetic substructure within the SCB appears to have a significantly smaller area than the corresponding H(alpha) emission. We conclude that SCBs originate in the lower corona around 0.1 R above the photosphere, propagate away from the flare center at speeds of 35-85 km/s, and have peak photosphere magnetic intensities of 148+/- 2.9 G. In light of these measurements, we infer SCBs to be distinctive chromospheric signatures of erupting coronal mass ejections.

  9. Sequential parameter estimation for stochastic systems

    Directory of Open Access Journals (Sweden)

    G. A. Kivman

    2003-01-01

    Full Text Available The quality of the prediction of dynamical system evolution is determined by the accuracy to which initial conditions and forcing are known. Availability of future observations permits reducing the effects of errors in assessment the external model parameters by means of a filtering algorithm. Usually, uncertainties in specifying internal model parameters describing the inner system dynamics are neglected. Since they are characterized by strongly non-Gaussian distributions (parameters are positive, as a rule, traditional Kalman filtering schemes are badly suited to reducing the contribution of this type of uncertainties to the forecast errors. An extension of the Sequential Importance Resampling filter (SIR is proposed to this aim. The filter is verified against the Ensemble Kalman filter (EnKF in application to the stochastic Lorenz system. It is shown that the SIR is capable of estimating the system parameters and to predict the evolution of the system with a remarkably better accuracy than the EnKF. This highlights a severe drawback of any Kalman filtering scheme: due to utilizing only first two statistical moments in the analysis step it is unable to deal with probability density functions badly approximated by the normal distribution.

  10. Online Sequential Extreme Learning Machine With Kernels.

    Science.gov (United States)

    Scardapane, Simone; Comminiello, Danilo; Scarpiniti, Michele; Uncini, Aurelio

    2015-09-01

    The extreme learning machine (ELM) was recently proposed as a unifying framework for different families of learning algorithms. The classical ELM model consists of a linear combination of a fixed number of nonlinear expansions of the input vector. Learning in ELM is hence equivalent to finding the optimal weights that minimize the error on a dataset. The update works in batch mode, either with explicit feature mappings or with implicit mappings defined by kernels. Although an online version has been proposed for the former, no work has been done up to this point for the latter, and whether an efficient learning algorithm for online kernel-based ELM exists remains an open problem. By explicating some connections between nonlinear adaptive filtering and ELM theory, in this brief, we present an algorithm for this task. In particular, we propose a straightforward extension of the well-known kernel recursive least-squares, belonging to the kernel adaptive filtering (KAF) family, to the ELM framework. We call the resulting algorithm the kernel online sequential ELM (KOS-ELM). Moreover, we consider two different criteria used in the KAF field to obtain sparse filters and extend them to our context. We show that KOS-ELM, with their integration, can result in a highly efficient algorithm, both in terms of obtained generalization error and training time. Empirical evaluations demonstrate interesting results on some benchmarking datasets.

  11. Sequential decoders for large MIMO systems

    KAUST Repository

    Ali, Konpal S.

    2014-05-01

    Due to their ability to provide high data rates, multiple-input multiple-output (MIMO) systems have become increasingly popular. Decoding of these systems with acceptable error performance is computationally very demanding. In this paper, we employ the Sequential Decoder using the Fano Algorithm for large MIMO systems. A parameter called the bias is varied to attain different performance-complexity trade-offs. Low values of the bias result in excellent performance but at the expense of high complexity and vice versa for higher bias values. Numerical results are done that show moderate bias values result in a decent performance-complexity trade-off. We also attempt to bound the error by bounding the bias, using the minimum distance of a lattice. The variations in complexity with SNR have an interesting trend that shows room for considerable improvement. Our work is compared against linear decoders (LDs) aided with Element-based Lattice Reduction (ELR) and Complex Lenstra-Lenstra-Lovasz (CLLL) reduction. © 2014 IFIP.

  12. Impact of controlling the sum of error probability in the sequential probability ratio test

    Directory of Open Access Journals (Sweden)

    Bijoy Kumarr Pradhan

    2013-05-01

    Full Text Available A generalized modified method is proposed to control the sum of error probabilities in sequential probability ratio test to minimize the weighted average of the two average sample numbers under a simple null hypothesis and a simple alternative hypothesis with the restriction that the sum of error probabilities is a pre-assigned constant to find the optimal sample size and finally a comparison is done with the optimal sample size found from fixed sample size procedure. The results are applied to the cases when the random variate follows a normal law as well as Bernoullian law.

  13. Reliability Evaluation of Distribution System Considering Sequential Characteristics of Distributed Generation

    Directory of Open Access Journals (Sweden)

    Sheng Wanxing

    2016-01-01

    Full Text Available In allusion to the randomness of output power of distributed generation (DG, a reliability evaluation model based on sequential Monte Carlo simulation (SMCS for distribution system with DG is proposed. Operating states of the distribution system can be sampled by SMCS in chronological order thus the corresponding output power of DG can be generated. The proposed method has been tested on feeder F4 of IEEE-RBTS Bus 6. The results show that reliability evaluation of distribution system considering the uncertainty of output power of DG can be effectively implemented by SMCS.

  14. On the error probability of general trellis codes with applications to sequential decoding

    Science.gov (United States)

    Johannesson, R.

    1977-01-01

    An upper bound on the average probability of error for maximum-likelihood decoding of the ensemble of random L-branch binary trellis codes of rate R = 1/n with distinction between memory length and tail length is given. It is shown that the bound is independent of the length L of the information sequence if the memory length exceeds the tail length by a specified amount that depends on L. Sequential decoding simulations using the stack algorithm were conducted to test the dependence of the undetected error probability on tail length and memory length, and the results corroborated the theory.

  15. Sequential Bayesian Detection: A Model-Based Approach

    Energy Technology Data Exchange (ETDEWEB)

    Candy, J V

    2008-12-08

    Sequential detection theory has been known for a long time evolving in the late 1940's by Wald and followed by Middleton's classic exposition in the 1960's coupled with the concurrent enabling technology of digital computer systems and the development of sequential processors. Its development, when coupled to modern sequential model-based processors, offers a reasonable way to attack physics-based problems. In this chapter, the fundamentals of the sequential detection are reviewed from the Neyman-Pearson theoretical perspective and formulated for both linear and nonlinear (approximate) Gauss-Markov, state-space representations. We review the development of modern sequential detectors and incorporate the sequential model-based processors as an integral part of their solution. Motivated by a wealth of physics-based detection problems, we show how both linear and nonlinear processors can seamlessly be embedded into the sequential detection framework to provide a powerful approach to solving non-stationary detection problems.

  16. Sequential Bayesian Detection: A Model-Based Approach

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, E J; Candy, J V

    2007-08-13

    Sequential detection theory has been known for a long time evolving in the late 1940's by Wald and followed by Middleton's classic exposition in the 1960's coupled with the concurrent enabling technology of digital computer systems and the development of sequential processors. Its development, when coupled to modern sequential model-based processors, offers a reasonable way to attack physics-based problems. In this chapter, the fundamentals of the sequential detection are reviewed from the Neyman-Pearson theoretical perspective and formulated for both linear and nonlinear (approximate) Gauss-Markov, state-space representations. We review the development of modern sequential detectors and incorporate the sequential model-based processors as an integral part of their solution. Motivated by a wealth of physics-based detection problems, we show how both linear and nonlinear processors can seamlessly be embedded into the sequential detection framework to provide a powerful approach to solving non-stationary detection problems.

  17. The sequential trauma score - a new instrument for the sequential mortality prediction in major trauma*

    Directory of Open Access Journals (Sweden)

    Huber-Wagner S

    2010-05-01

    Full Text Available Abstract Background There are several well established scores for the assessment of the prognosis of major trauma patients that all have in common that they can be calculated at the earliest during intensive care unit stay. We intended to develop a sequential trauma score (STS that allows prognosis at several early stages based on the information that is available at a particular time. Study design In a retrospective, multicenter study using data derived from the Trauma Registry of the German Trauma Society (2002-2006, we identified the most relevant prognostic factors from the patients basic data (P, prehospital phase (A, early (B1, and late (B2 trauma room phase. Univariate and logistic regression models as well as score quality criteria and the explanatory power have been calculated. Results A total of 2,354 patients with complete data were identified. From the patients basic data (P, logistic regression showed that age was a significant predictor of survival (AUCmodel p, area under the curve = 0.63. Logistic regression of the prehospital data (A showed that blood pressure, pulse rate, Glasgow coma scale (GCS, and anisocoria were significant predictors (AUCmodel A = 0.76; AUCmodel P + A = 0.82. Logistic regression of the early trauma room phase (B1 showed that peripheral oxygen saturation, GCS, anisocoria, base excess, and thromboplastin time to be significant predictors of survival (AUCmodel B1 = 0.78; AUCmodel P +A + B1 = 0.85. Multivariate analysis of the late trauma room phase (B2 detected cardiac massage, abbreviated injury score (AIS of the head ≥ 3, the maximum AIS, the need for transfusion or massive blood transfusion, to be the most important predictors (AUCmodel B2 = 0.84; AUCfinal model P + A + B1 + B2 = 0.90. The explanatory power - a tool for the assessment of the relative impact of each segment to mortality - is 25% for P, 7% for A, 17% for B1 and 51% for B2. A spreadsheet for the easy calculation of the sequential trauma

  18. 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

  19. Combined versus sequential injection of mepivacaine and ropivacaine for supraclavicular nerve blocks.

    Science.gov (United States)

    Roberman, Dmitry; Arora, Harendra; Sessler, Daniel I; Ritchey, Michael; You, Jing; Kumar, Priya

    2011-01-01

    An ideal local anesthetic with rapid onset and prolonged duration has yet to be developed. Clinicians use mixtures of local anesthetics in an attempt to combine their advantages. We tested the hypothesis that sequential supraclavicular injection of 1.5% mepivacaine followed 90 secs later by 0.5% ropivacaine speeds onset of sensory block and prolongs duration of analgesia compared with simultaneous injection of the same 2 local anesthetics. We enrolled 103 patients undergoing surgery suitable for supraclavicular anesthesia. The primary outcome was time to 4-nerve sensory block onset in each of the 4 major nerve distributions: median, ulnar, radial, and musculocutaneous. Secondary outcomes included time to onset of first sensory block, time to complete motor block, duration of analgesia, pain scores at rest and with movement, and total opioid consumption. Outcomes were compared using the Kaplan-Meier analysis with the log-rank test or the analysis of variance, as appropriate. Times to 4-nerve sensory block onset were not different between sequential and combined anesthetic administration. The time to complete motor block onset was faster in the combined group as compared with the sequential. There were not significant differences between the 2 randomized groups in other secondary outcomes, such as the time to onset of first sensory block, the duration of analgesia, the pain scores at rest or with movement, or the total opioid consumption. Sequential injection of 1.5% mepivacaine followed 90 secs later by 0.5% ropivacaine provides no advantage compared with simultaneous injection of the same doses. Copyright © 2011 by American Society of Regional Anesthesia and Pain Medicine

  20. Sequential optimality conditions for composed convex optimization problems

    Science.gov (United States)

    Bot, Radu Ioan; Csetnek, Ernö Robert; Wanka, Gert

    2008-06-01

    Using a general approach which provides sequential optimality conditions for a general convex optimization problem, we derive necessary and sufficient optimality conditions for composed convex optimization problems. Further, we give sequential characterizations for a subgradient of the precomposition of a K-increasing lower semicontinuous convex function with a K-convex and K-epi-closed (continuous) function, where K is a nonempty convex cone. We prove that several results from the literature dealing with sequential characterizations of subgradients are obtained as particular cases of our results. We also improve the above mentioned statements.

  1. Fast sequential Monte Carlo methods for counting and optimization

    CERN Document Server

    Rubinstein, Reuven Y; Vaisman, Radislav

    2013-01-01

    A comprehensive account of the theory and application of Monte Carlo methods Based on years of research in efficient Monte Carlo methods for estimation of rare-event probabilities, counting problems, and combinatorial optimization, Fast Sequential Monte Carlo Methods for Counting and Optimization is a complete illustration of fast sequential Monte Carlo techniques. The book provides an accessible overview of current work in the field of Monte Carlo methods, specifically sequential Monte Carlo techniques, for solving abstract counting and optimization problems. Written by authorities in the

  2. Direct quantum process tomography via measuring sequential weak values of incompatible observables.

    Science.gov (United States)

    Kim, Yosep; Kim, Yong-Su; Lee, Sang-Yun; Han, Sang-Wook; Moon, Sung; Kim, Yoon-Ho; Cho, Young-Wook

    2018-01-15

    The weak value concept has enabled fundamental studies of quantum measurement and, recently, found potential applications in quantum and classical metrology. However, most weak value experiments reported to date do not require quantum mechanical descriptions, as they only exploit the classical wave nature of the physical systems. In this work, we demonstrate measurement of the sequential weak value of two incompatible observables by making use of two-photon quantum interference so that the results can only be explained quantum physically. We then demonstrate that the sequential weak value measurement can be used to perform direct quantum process tomography of a qubit channel. Our work not only demonstrates the quantum nature of weak values but also presents potential new applications of weak values in analyzing quantum channels and operations.

  3. Large-scale sequential quadratic programming algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Eldersveld, S.K.

    1992-09-01

    The problem addressed is the general nonlinear programming problem: finding a local minimizer for a nonlinear function subject to a mixture of nonlinear equality and inequality constraints. The methods studied are in the class of sequential quadratic programming (SQP) algorithms, which have previously proved successful for problems of moderate size. Our goal is to devise an SQP algorithm that is applicable to large-scale optimization problems, using sparse data structures and storing less curvature information but maintaining the property of superlinear convergence. The main features are: 1. The use of a quasi-Newton approximation to the reduced Hessian of the Lagrangian function. Only an estimate of the reduced Hessian matrix is required by our algorithm. The impact of not having available the full Hessian approximation is studied and alternative estimates are constructed. 2. The use of a transformation matrix Q. This allows the QP gradient to be computed easily when only the reduced Hessian approximation is maintained. 3. The use of a reduced-gradient form of the basis for the null space of the working set. This choice of basis is more practical than an orthogonal null-space basis for large-scale problems. The continuity condition for this choice is proven. 4. The use of incomplete solutions of quadratic programming subproblems. Certain iterates generated by an active-set method for the QP subproblem are used in place of the QP minimizer to define the search direction for the nonlinear problem. An implementation of the new algorithm has been obtained by modifying the code MINOS. Results and comparisons with MINOS and NPSOL are given for the new algorithm on a set of 92 test problems.

  4. Isochronous sequential presentation helps children orient their attention in time.

    Directory of Open Access Journals (Sweden)

    Katherine A Johnson

    2016-09-01

    Full Text Available Knowing when an event is likely to occur allows attentional resources to be oriented towards that moment in time, enhancing processing of the event. We previously found that children (mean age 11 years are unable to use endogenous temporal cues (line length to orient attention in time, despite being able to use endogenous spatial cues (arrows to orient attention in space. Arrow cues, however, may have proved beneficial by engaging exogenous (automatic, as well as endogenous (voluntary, orienting mechanisms. We therefore conducted two studies in which the exogenous properties of visual temporal cues were increased, to examine whether this helped children orient their attention in time. In the first study, the location of an imperative target was predicted by the direction of a left or right spatial arrow cue while its onset was predicted by the relative duration of a short or long temporal cue. To minimise the influence of rhythmic entrainment in the temporal condition, target onset time (500ms/1100ms was deliberately chosen so as not to precisely match the duration of the temporal cue (100ms/400ms. Targets appeared either at cued locations/onset times (valid trials or at unexpected locations/onset times (invalid trials. Adults’ response times were significantly slower for invalid versus valid trials, in both spatial and temporal domains. Despite being slowed by invalid spatial cues, children (mean age 10.7 years were unperturbed by invalid temporal cues, suggesting that these duration-based temporal cues did not help them orient attention in time. In the second study, we enhanced the exogenous properties of temporal cues further, by presenting multiple temporal cues in an isochronous (rhythmic sequence. Again, to minimise automatic entrainment, target onset did not match the isochronous interval. Children (mean age 11.4 years, as well as adults, were now significantly slowed by invalid cues in both the temporal and spatial dimension. The

  5. Sequential ensemble-based optimal design for parameter estimation: SEQUENTIAL ENSEMBLE-BASED OPTIMAL DESIGN

    Energy Technology Data Exchange (ETDEWEB)

    Man, Jun [Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou China; Zhang, Jiangjiang [Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou China; Li, Weixuan [Pacific Northwest National Laboratory, Richland Washington USA; Zeng, Lingzao [Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou China; Wu, Laosheng [Department of Environmental Sciences, University of California, Riverside California USA

    2016-10-01

    The ensemble Kalman filter (EnKF) has been widely used in parameter estimation for hydrological models. The focus of most previous studies was to develop more efficient analysis (estimation) algorithms. On the other hand, it is intuitively understandable that a well-designed sampling (data-collection) strategy should provide more informative measurements and subsequently improve the parameter estimation. In this work, a Sequential Ensemble-based Optimal Design (SEOD) method, coupled with EnKF, information theory and sequential optimal design, is proposed to improve the performance of parameter estimation. Based on the first-order and second-order statistics, different information metrics including the Shannon entropy difference (SD), degrees of freedom for signal (DFS) and relative entropy (RE) are used to design the optimal sampling strategy, respectively. The effectiveness of the proposed method is illustrated by synthetic one-dimensional and two-dimensional unsaturated flow case studies. It is shown that the designed sampling strategies can provide more accurate parameter estimation and state prediction compared with conventional sampling strategies. Optimal sampling designs based on various information metrics perform similarly in our cases. The effect of ensemble size on the optimal design is also investigated. Overall, larger ensemble size improves the parameter estimation and convergence of optimal sampling strategy. Although the proposed method is applied to unsaturated flow problems in this study, it can be equally applied in any other hydrological problems.

  6. Chronic mechanical neck pain in adults treated by manual therapy: a systematic review of change scores in randomized controlled trials of a single session

    National Research Council Canada - National Science Library

    Vernon, Howard; Humphreys, Barry Kim

    2008-01-01

    We report a systematic analysis of group change scores of subjects with chronic neck pain not due to whiplash and without headache or arm pain, in randomized clinical trials of a single session of manual therapy...

  7. Diabetes-specific enteral nutrition formula in hyperglycemic, mechanically ventilated, critically ill patients: a prospective, open-label, blind-randomized, multicenter study.

    Science.gov (United States)

    Mesejo, Alfonso; Montejo-González, Juan Carlos; Vaquerizo-Alonso, Clara; Lobo-Tamer, Gabriela; Zabarte-Martinez, Mercedes; Herrero-Meseguer, Jose Ignacio; Acosta-Escribano, Jose; Blesa-Malpica, Antonio; Martinez-Lozano, Fátima

    2015-11-09

    Although standard enteral nutrition is universally accepted, the use of disease-specific formulas for hyperglycemic patients is still controversial. This study examines whether a high-protein diabetes-specific formula reduces insulin needs, improves glycemic control and reduces ICU-acquired infection in critically ill, hyperglycemic patients on mechanical ventilation (MV). This was a prospective, open-label, randomized (web-based, blinded) study conducted at nine Spanish ICUs. The patient groups established according to the high-protein formula received were: group A, new-generation diabetes-specific formula; group B, standard control formula; group C, control diabetes-specific formula. Inclusion criteria were: expected enteral nutrition ≥5 days, MV, baseline glucose >126 mg/dL on admission or >200 mg/dL in the first 48 h. Exclusion criteria were: APACHE II ≤10, insulin-dependent diabetes, renal or hepatic failure, treatment with corticosteroids, immunosuppressants or lipid-lowering drugs and body mass index ≥40 kg/m(2). The targeted glucose level was 110-150 mg/dL. Glycemic variability was calculated as the standard deviation, glycemic lability index and coefficient of variation. Acquired infections were recorded using published consensus criteria for critically ill patients. Data analysis was on an intention-to-treat basis. Over a 2-year period, 157 patients were consecutively enrolled (A 52, B 53 and C 52). Compared with the standard control formula, the new formula gave rise to lower insulin requirement (19.1 ± 13.1 vs. 23.7 ± 40.1 IU/day, p pneumonia (p nutrition formula were produced on hospital stay or mortality. In these high-risk ICU patients, both diabetes-specific formulas lowered insulin requirements, improved glycemic control and reduced the risk of acquired infections relative to the standard formula. Compared with the control-specific formula, the new-generation formula also improved capillary glycemia. Clinicaltrials.gov NCT1233726 .

  8. Prevention of depression and anxiety in adolescents: A randomized controlled trial testing the efficacy and mechanisms of Internet-based self-help problem-solving therapy

    Directory of Open Access Journals (Sweden)

    Schuurmans Josien

    2009-10-01

    Full Text Available Abstract Background Even though depression and anxiety are highly prevalent in adolescence, youngsters are not inclined to seek help in regular healthcare. Therapy through the Internet, however, has been found to appeal strongly to young people. The main aim of the present study is to examine the efficacy of preventive Internet-based guided self-help problem-solving therapy with adolescents reporting depressive and anxiety symptoms. A secondary objective is to test potential mediating and moderating variables in order to gain insight into how the intervention works and for whom it works best. Methods/design This study is a randomized controlled trial with an intervention condition group and a wait-list control group. The intervention condition group receives Internet-based self-help problem-solving therapy. Support is provided by a professional and delivered through email. Participants in the wait-list control group receive the intervention four months later. The study population consists of adolescents (12-18-year-olds from the general population who report mild to moderate depressive and/or anxiety symptoms and are willing to complete a self-help course. Primary outcomes are symptoms of depression and anxiety. Secondary outcomes are quality of life, social anxiety, and cost-effectiveness. The following variables are examined for their moderating role: demographics, motivation, treatment credibility and expectancy, externalizing behaviour, perceived social support from parents and friends, substance use, the experience of important life events, physical activity, the quality of the therapeutic alliance, and satisfaction. Mediator variables include problem-solving skills, worrying, mastery, and self-esteem. Data are collected at baseline and at 3 weeks, 5 weeks, 4 months, 8 months, and 12 months after baseline. Both intention-to-treat and completer analyses will be conducted. Discussion This study evaluates the efficacy and mechanisms of

  9. Cerebral mechanism of puncturing at He-Mu point combination for functional dyspepsia: study protocol for a randomized controlled parallel trial

    Directory of Open Access Journals (Sweden)

    Shuai Yin

    2017-01-01

    Full Text Available Acupuncture is widely used to treat functional dyspepsia with satisfactory outcomes. Combination of the He and Mu acupoints is commonly used and has a synergistic effect on functional dyspepsia; however, its underlying mechanisms remain unclear. Therefore, a randomized controlled parallel clinical trial is currently underway at Chengdu University of Traditional Chinese Medicine, China. This trial is designed to explore the efficacy of and central responses to the He-Mu point combination in patients with functional dyspepsia using functional magnetic resonance imaging. A total of 105 patients with functional dyspepsia will be allocated into 3 groups: the low-He point group (puncturing at Zusanli (ST36, Mu point group (puncturing at Zhongwan (CV12, and He-Mu point combination group (puncturing at ST36 and CV12. Every participant will receive 20 sessions of manual acupuncture for 4 weeks. The needles will be inserted perpendicularly to a depth of 1 to 2 cun. The angle of rotation and twisting will range from 90 to 180 degrees, while lifting and thrusting will range from 0.3 to 0.5 cm. The various manipulations will be performed 60 to 90 times per minute. The needles will remain in place for 30 minutes, during which manipulation will be applied every 10 minutes. Magnetic resonance imaging will be performed before and after 20 sessions of acupuncture. The primary outcome is symptom improvement according to the Chinese version of the Nepean Dyspepsia Index. Secondary outcomes include the Leeds dyspepsia questionnaire, Self-Rating Anxiety Scale, Self-Rating Depression Scale, Beck Anxiety Inventory, Beck Depression Inventory, and visual analogue scale scores before and after 10 and 20 sessions of acupuncture. Needle sensation and adverse events will be used to assess the therapeutic effects. This study will promote more widespread awareness of the benefits of acupoint combination in the clinical setting and provide a further explanation of the

  10. Synthesizing genetic sequential logic circuit with clock pulse generator

    National Research Council Canada - National Science Library

    Chuang, Chia-Hua; Lin, Chun-Liang

    2014-01-01

    .... This paper presents a genetic sequential logic circuit with a clock pulse generator based on a synthesized genetic oscillator, which generates a consecutive clock signal whose frequency is an inverse...

  11. Process tomography via sequential measurements on a single quantum system

    CSIR Research Space (South Africa)

    Bassa, H

    2015-09-01

    Full Text Available The authors utilize a discrete (sequential) measurement protocol to investigate quantum process tomography of a single two-level quantum system, with an unknown initial state, undergoing Rabi oscillations. The ignorance of the dynamical parameters...

  12. On Riesz-Caputo Formulation for Sequential Fractional Variational Principles

    Directory of Open Access Journals (Sweden)

    Fahd Jarad

    2012-01-01

    Full Text Available This paper deals with sequential Riesz-Caputo fractional variational problems with and without the presence of delay in the state variables and their derivatives. In both cases the necessary conditions for the optimal control are reported.

  13. Ultrasound Vector Flow Imaging: Part I: Sequential Systems

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Nikolov, Svetoslav Ivanov; Yu, Alfred C. H.

    2016-01-01

    The paper gives a review of the most important methods for blood velocity vector flow imaging (VFI) for conventional, sequential data acquisition. This includes multibeam methods, speckle tracking, transverse oscillation, color flow mapping derived vector flow imaging, directional beamforming, an...

  14. sequential low cost interventions double hand hygiene rates among

    African Journals Online (AJOL)

    East African Medical Journal Vol. 91 No. 2 February 2014. SEQUENTIAL LOW COST INTERVENTIONS DOUBLE HAND HYGIENE RATES AMONG MEDICAL TEAMS IN A. RESOURCE LIMITED SETTING. RESULTS OF A HAND HYGIENE QUALITY IMPROVEMENT PROJECT CONDUCTED. AT UNIVERSITY TEACHING ...

  15. Sequential Low Cost Interventions Double Hand Hygiene Rates ...

    African Journals Online (AJOL)

    Sequential Low Cost Interventions Double Hand Hygiene Rates Among Medical Teams in a Resource Limited Setting. Results of a Hand Hygiene Quality Improvement Project Conducted At University Teaching Hospital of Kigali (Chuk), Kigali, Rwanda.

  16. Auditory cortical maturation in children with sequential bilateral cochlear implants.

    NARCIS (Netherlands)

    Sparreboom, M.; Beynon, A.J.; Snik, A.F.M.; Mylanus, E.A.M.

    2014-01-01

    OBJECTIVE: To assess the effect of sequential bilateral cochlear implantation on auditory, cortical maturation after various periods of unilateral cochlear implant use. STUDY DESIGN: Prospective cohort study. SETTING: Tertiary academic referral center. PATIENTS: Thirty prelingually deaf children,

  17. Multi-Level Sequential Pattern Mining Based on Prime Encoding

    Science.gov (United States)

    Lianglei, Sun; Yun, Li; Jiang, Yin

    Encoding is not only to express the hierarchical relationship, but also to facilitate the identification of the relationship between different levels, which will directly affect the efficiency of the algorithm in the area of mining the multi-level sequential pattern. In this paper, we prove that one step of division operation can decide the parent-child relationship between different levels by using prime encoding and present PMSM algorithm and CROSS-PMSM algorithm which are based on prime encoding for mining multi-level sequential pattern and cross-level sequential pattern respectively. Experimental results show that the algorithm can effectively extract multi-level and cross-level sequential pattern from the sequence database.

  18. Mechanisms involved in symptomatic myocardial bridging

    NARCIS (Netherlands)

    Hazenberg, A. J. C.; Jessurun, G. A. J.; Tio, R. A.

    Background. In patients with extensive myocardial bridging, evaluation of its clinical significance remains a challenge. Hypothesis. Sequential invasive testing is feasible and gives more insight into the pathophysiological mechanism of bridging-related angina. Methods. Twelve patients with chest

  19. Sequential Organization and Room Reverberation for Speech Segregation

    Science.gov (United States)

    2012-02-28

    rooms. Wechoose two acoustic rooms with the reverberation time (T^)) equal to 0.3 and 0.5 s, respectively. In each room, two RIRs corresponding to...Labeling accuracy of the proposed and comparison systems shown as a function of reverberation time for (a) two-talker and (b) three-talker mixtures...of reverberation time . This sequential organization approach was published in a 2010 paper by J. Woodruff and D.L. Wang, entitled ’’Sequential

  20. Computational Cognitive Neuroscience Modeling of Sequential Skill Learning

    Science.gov (United States)

    2016-09-21

    AFRL-AFOSR-VA-TR-2016-0320 Computational Cognitive Neuroscience Modeling of Sequential Skill Learning David Schnyer UNIVERSITY OF TEXAS AT AUSTIN...2015-30/06/2016 4. TITLE AND SUBTITLE Computational Cognitive Neuroscience Modeling of Sequential Skill Learning 5a. CONTRACT NUMBER 5b. GRANT NUMBER...5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) The University of Texas at Austin 108 E Dean Keeton Stop A8000 Austin, TX

  1. Concatenated coding system with iterated sequential inner decoding

    DEFF Research Database (Denmark)

    Jensen, Ole Riis; Paaske, Erik

    1995-01-01

    We describe a concatenated coding system with iterated sequential inner decoding. The system uses convolutional codes of very long constraint length and operates on iterations between an inner Fano decoder and an outer Reed-Solomon decoder......We describe a concatenated coding system with iterated sequential inner decoding. The system uses convolutional codes of very long constraint length and operates on iterations between an inner Fano decoder and an outer Reed-Solomon decoder...

  2. A Trust-region-based Sequential Quadratic Programming Algorithm

    DEFF Research Database (Denmark)

    Henriksen, Lars Christian; Poulsen, Niels Kjølstad

    This technical note documents the trust-region-based sequential quadratic programming algorithm used in other works by the authors. The algorithm seeks to minimize a convex nonlinear cost function subject to linear inequalty constraints and nonlinear equality constraints.......This technical note documents the trust-region-based sequential quadratic programming algorithm used in other works by the authors. The algorithm seeks to minimize a convex nonlinear cost function subject to linear inequalty constraints and nonlinear equality constraints....

  3. Sequential unilateral lung volume reduction for emphysema - Stretching the benefit.

    Science.gov (United States)

    Khorramnia, Sadie; Holsworth, Lynda; Mestitz, Hugh; Westall, Glen P; Williams, Trevor J; Gooi, Julian H; Snell, Gregory I

    2017-01-01

    Bronchoscopic Lung Volume Reduction (BLVR) and Surgical Lung Volume Reduction (SLVR) and are two different approaches used to remodel severely emphysematous lungs to improve lung function and quality-of-life. We present a case initially referred for lung transplantation, where sequential left upper lobe BLVR and 7 years later right upper lobe SLVR, providing enduring physiological and functional improvement. The potential for sustained benefit via sequential unilateral lung volume reduction is under-appreciated.

  4. (Pea)nuts and bolts of visual narrative: Structure and meaning in sequential image comprehension

    Science.gov (United States)

    Cohn, Neil; Paczynski, Martin; Jackendoff, Ray; Holcomb, Phillip J.; Kuperberg, Gina R.

    2012-01-01

    Just as syntax differentiates coherent sentences from scrambled word strings, the comprehension of sequential images must also use a cognitive system to distinguish coherent narrative sequences from random strings of images. We conducted experiments analogous to two classic studies of language processing to examine the contributions of narrative structure and semantic relatedness to processing sequential images. We compared four types of comic strips: 1) Normal sequences with both structure and meaning, 2) Semantic Only sequences (in which the panels were related to a common semantic theme, but had no narrative structure), 3) Structural Only sequences (narrative structure but no semantic relatedness), and 4) Scrambled sequences of randomly-ordered panels. In Experiment 1, participants monitored for target panels in sequences presented panel-by-panel. Reaction times were slowest to panels in Scrambled sequences, intermediate in both Structural Only and Semantic Only sequences, and fastest in Normal sequences. This suggests that both semantic relatedness and narrative structure offer advantages to processing. Experiment 2 measured ERPs to all panels across the whole sequence. The N300/N400 was largest to panels in both the Scrambled and Structural Only sequences, intermediate in Semantic Only sequences and smallest in the Normal sequences. This implies that a combination of narrative structure and semantic relatedness can facilitate semantic processing of upcoming panels (as reflected by the N300/N400). Also, panels in the Scrambled sequences evoked a larger left-lateralized anterior negativity than panels in the Structural Only sequences. This localized effect was distinct from the N300/N400, and appeared despite the fact that these two sequence types were matched on local semantic relatedness between individual panels. These findings suggest that sequential image comprehension uses a narrative structure that may be independent of semantic relatedness. Altogether

  5. Antipyretic therapy in critically ill patients with established sepsis: a trial sequential analysis.

    Directory of Open Access Journals (Sweden)

    Zhongheng Zhang

    Full Text Available antipyretic therapy for patients with sepsis has long been debated. The present study aimed to explore the beneficial effect of antipyretic therapy for ICU patients with sepsis.systematic review and trial sequential analysis of randomized controlled trials.Pubmed, Scopus, EBSCO and EMBASE were searched from inception to August 5, 2014.Mortality was dichotomized as binary outcome variable and odds ratio (OR was chosen to be the summary statistic. Pooled OR was calculated by using DerSimonian and Laird method. Statistical heterogeneity was assessed by using the statistic I2. Trial sequential analysis was performed to account for the small number of trials and patients.A total of 6 randomized controlled trials including 819 patients were included into final analysis. Overall, there was no beneficial effect of antipyretic therapy on mortality risk in patients with established sepsis (OR: 1.02, 95% CI: 0.50-2.05. The required information size (IS was 2582 and our analysis has not yet reached half of the IS. The Z-curve did not cross the O'Brien-Fleming α-spending boundary or reach the futility, indicating that the non-significant result was probably due to lack of statistical power.our study fails to identify any beneficial effect of antipyretic therapy on ICU patients with established diagnosis of sepsis. Due to limited number of total participants, more studies are needed to make a conclusive and reliable analysis.

  6. Change in defense mechanisms and coping patterns during the course of 2-year-long psychotherapy and psychoanalysis for recurrent depression: a pilot study of a randomized controlled trial.

    Science.gov (United States)

    Kramer, Ueli; de Roten, Yves; Perry, J Christopher; Despland, Jean-Nicolas

    2013-07-01

    Very little research has been conducted so far to study the potential mechanisms of change in long-term active psychological treatments of recurrent depression. The present pilot randomized controlled trial aimed to determine the feasibility of studying the change process occurring in patients during the course of 2-year-long dynamic psychotherapy, psychoanalysis, and cognitive therapy, as compared with clinical management. In total, eight outpatients presenting with recurrent depression, two patients per treatment arm, were included. All patients were randomly assigned to one of the four treatment conditions. Defense mechanisms and coping patterns were assessed using validated observer-rated methodology based on transcribed, semistructured follow-along independent dynamic interviews. The results indicated that, whereas some patients in the active treatments changed on the symptomatic levels, some others remained unchanged during the course of their 2-year-long treatment. However, with regard to potential mechanisms of change in these patients, changes in defense mechanisms and coping patterns were revealed to be important processes over time in successful therapies and, to a lesser extent, in less successful treatments. No change was found either on outcome or on the process measure for the control condition, that is, clinical management. These results are discussed along with previous data comparing change in defense mechanisms and coping during the course of treatments.

  7. Sequential structural and fluid dynamic numerical simulations of a stented bifurcated coronary artery.

    Science.gov (United States)

    Morlacchi, Stefano; Chiastra, Claudio; Gastaldi, Dario; Pennati, Giancarlo; Dubini, Gabriele; Migliavacca, Francesco

    2011-12-01

    Despite their success, stenting procedures are still associated to some clinical problems like sub-acute thrombosis and in-stent restenosis. Several clinical studies associate these phenomena to a combination of both structural and hemodynamic alterations caused by stent implantation. Recently, numerical models have been widely used in the literature to investigate stenting procedures but always from either a purely structural or fluid dynamic point of view. The aim of this work is the implementation of sequential structural and fluid dynamic numerical models to provide a better understanding of stenting procedures in coronary bifurcations. In particular, the realistic geometrical configurations obtained with structural simulations were used to create the fluid domains employed within transient fluid dynamic analyses. This sequential approach was applied to investigate the final kissing balloon (FKB) inflation during the provisional side branch technique. Mechanical stresses in the arterial wall and the stent as well as wall shear stresses along the arterial wall were examined before and after the FKB deployment. FKB provoked average mechanical stresses in the arterial wall almost 2.5 times higher with respect to those induced by inflation of the stent in the main branch only. Results also enlightened FKB benefits in terms of improved local blood flow pattern for the side branch access. As a drawback, the FKB generates a larger region of low wall shear stress. In particular, after FKB the percentage of area characterized by wall shear stresses lower than 0.5 Pa was 79.0%, while before the FKB it was 62.3%. For these reasons, a new tapered balloon dedicated to bifurcations was proposed. The inclusion of the modified balloon has reduced the mechanical stresses in the proximal arterial vessel to 40% and the low wall shear stress coverage area to 71.3%. In conclusion, these results show the relevance of the adopted sequential approach to study the wall mechanics and

  8. Sequential Phase 1 and Phase 2 randomized, controlled trials of the safety, immunogenicity and efficacy of combined pre-erythrocytic vaccine antigens RTS,S and TRAP formulated with AS02 Adjuvant System in healthy, malaria naïve adults.

    Science.gov (United States)

    Kester, Kent E; Gray Heppner, D; Moris, Philippe; Ofori-Anyinam, Opokua; Krzych, Urszula; Tornieporth, Nadia; McKinney, Denise; Delchambre, Martine; Ockenhouse, Christian F; Voss, Gerald; Holland, Carolyn; Beckey, Jolie Palensky; Ballou, W Ripley; Cohen, Joe

    2014-11-20

    In an attempt to improve the efficacy of the candidate malaria vaccine RTS,S/AS02, two studies were conducted in 1999 in healthy volunteers of RTS,S/AS02 in combination with recombinant Plasmodium falciparum thrombospondin-related anonymous protein (TRAP). In a Phase 1 safety and immunogenicity study, volunteers were randomized to receive TRAP/AS02 (N=10), RTS,S/AS02 (N=10), or RTS,S+TRAP/AS02 (N=20) at 0, 1 and 6-months. In a Phase 2 challenge study, subjects were randomized to receive either RTS,S+TRAP/AS02 (N=25) or TRAP/AS02 (N=10) at 0 and 1-month, or to a challenge control group (N=8). In both studies, the combination vaccine had an acceptable safety profile and was acceptably tolerated. Antigen-specific antibodies, lymphoproliferative responses, and IFN-γ production by ELISPOT assay elicited with the combination vaccine were qualitatively similar to those generated by the single component vaccines. However, post-dose 2 anti-CS antibodies in the RTS,S+TRAP/AS02 vaccine recipients were lower than in the RTS,S/AS02 vaccine recipients. After challenge, 10 of 11 RTS,S+TRAP/AS02 vaccinees, 5 of 5 TRAP/AS02 vaccinees, and 8 of 8 infectivity controls developed parasitemia, with median pre-patent periods of 13.0, 11.0, and 12.0 days, respectively. The absence of any prevention or delay of parasitemia by TRAP/AS02 suggests no apparent added value of TRAP/AS02 as a candidate vaccine. The absence of significant protection or delay of parasitemia in the 11 RTS,S+TRAP/AS02 vaccine recipients contrasts with previous 2 dose studies of RTS,S/AS02. The small sample size did not permit identifying statistically significant differences between the study arms. However, we speculate, within the constraints of the challenge study, that the presence of the TRAP antigen may have interfered with the vaccine efficacy previously observed with this regimen of RTS,S/AS02, and that any future TRAP-based vaccines should consider employing alternative vaccine platforms. Copyright © 2014

  9. CACTI: free, open-source software for the sequential coding of behavioral interactions.

    Science.gov (United States)

    Glynn, Lisa H; Hallgren, Kevin A; Houck, Jon M; Moyers, Theresa B

    2012-01-01

    The sequential analysis of client and clinician speech in psychotherapy sessions can help to identify and characterize potential mechanisms of treatment and behavior change. Previous studies required coding systems that were time-consuming, expensive, and error-prone. Existing software can be expensive and inflexible, and furthermore, no single package allows for pre-parsing, sequential coding, and assignment of global ratings. We developed a free, open-source, and adaptable program to meet these needs: The CASAA Application for Coding Treatment Interactions (CACTI). Without transcripts, CACTI facilitates the real-time sequential coding of behavioral interactions using WAV-format audio files. Most elements of the interface are user-modifiable through a simple XML file, and can be further adapted using Java through the terms of the GNU Public License. Coding with this software yields interrater reliabilities comparable to previous methods, but at greatly reduced time and expense. CACTI is a flexible research tool that can simplify psychotherapy process research, and has the potential to contribute to the improvement of treatment content and delivery.

  10. CACTI: free, open-source software for the sequential coding of behavioral interactions.

    Directory of Open Access Journals (Sweden)

    Lisa H Glynn

    Full Text Available The sequential analysis of client and clinician speech in psychotherapy sessions can help to identify and characterize potential mechanisms of treatment and behavior change. Previous studies required coding systems that were time-consuming, expensive, and error-prone. Existing software can be expensive and inflexible, and furthermore, no single package allows for pre-parsing, sequential coding, and assignment of global ratings. We developed a free, open-source, and adaptable program to meet these needs: The CASAA Application for Coding Treatment Interactions (CACTI. Without transcripts, CACTI facilitates the real-time sequential coding of behavioral interactions using WAV-format audio files. Most elements of the interface are user-modifiable through a simple XML file, and can be further adapted using Java through the terms of the GNU Public License. Coding with this software yields interrater reliabilities comparable to previous methods, but at greatly reduced time and expense. CACTI is a flexible research tool that can simplify psychotherapy process research, and has the potential to contribute to the improvement of treatment content and delivery.

  11. Re: Sequential Combination of Mitomycin C Plus Bacillus Calmette-Guerin (BCG Is More Effective but More Toxic Than BCG Alone in Patients with Non–Muscle-Invasive Bladder Cancer in Intermediate-and High-Risk Patients: Final Outcome of CUETO 93009, A Randomized Prospective Trial

    Directory of Open Access Journals (Sweden)

    Eduardo Solsona

    2015-03-01

    Full Text Available EAU Guideline recommendation in non-muscle invasive bladder cancer (NMIBC is that patients who have intermediate or high risk for recurrence and intermediate risk for progression should receive early single dose intravesical chemotherapy followed by maintenance or a minimum of 1 year of BCG. Intravesical Mitomycin C (MMC plus Bacillus Calmette-Guerin (BCG treatment schemes were studied. However, MMC+BCG were not found to be superior to BCG alone (1,2. In the present study, authors conducted a randomized prospective trial on combination of MMC+BCG (n=192 or BCG alone (n=190. EORTC definition of NMIBC intermediate and high-risk patientswere included in the study. Unlike previous reported studies, disease-free interval at 5 years for MMC+BCG was found to be significantly better (HR: 0.57; 95% CI, 0.39 -0,83; p=0.003 than BCG alone. In an interim analysis, excessive toxicity was observed in MMC+BCG than BCG alone group. Consequently MMC dose was reduced from 30 mg to 10 mg. However, toxicity remained higher in the MMC+BCG group. Especially in EORTC highrisk NMIBCs, MMC+BCG is better than BCG alone, but with worse toxicity. In conclusion, despite some limitations, the results of Solsona et al. provided a new potential bladder-sparing management alternative, but it has higher toxicity. Additional studies are required to confirm these findings and availability of a less toxic intravesical chemotherapeutic agent.

  12. Body fat loss and compensatory mechanisms in response to different doses of aerobic exercise - a randomized controlled trial in overweight sedentary males

    DEFF Research Database (Denmark)

    Larsen, Mads Rosenkilde; Auerbach, Pernille Landrock; Reichkendler, Michala Holm

    2012-01-01

    is limited. A randomized controlled trial was performed in healthy sedentary moderately overweight young men to examine the effects of increasing doses of aerobic exercise on body composition, accumulated energy balance, and the degree of compensation. Eighteen participants were randomized to a continuous...... sedentary control group, 21 to a moderate (MOD; 300 kcal/day) and 22 to a high dose (HIGH; 600 kcal/day) exercise group for 13 weeks, corresponding to approximately 30 and 60 minutes of daily aerobic exercise, respectively. Body weight (MOD: -3.6kg, P...

  13. Effects of patient-directed music intervention on anxiety and sedative exposure in critically ill patients receiving mechanical ventilatory support: a randomized clinical trial.

    Science.gov (United States)

    Chlan, Linda L; Weinert, Craig R; Heiderscheit, Annie; Tracy, Mary Fran; Skaar, Debra J; Guttormson, Jill L; Savik, Kay

    2013-06-12

    Alternatives to sedative medications, such as music, may alleviate the anxiety associated with ventilatory support. To test whether listening to self-initiated patient-directed music (PDM) can reduce anxiety and sedative exposure during ventilatory support in critically ill patients. Randomized clinical trial that enrolled 373 patients from 12 intensive care units (ICUs) at 5 hospitals in the Minneapolis-St Paul, Minnesota, area receiving acute mechanical ventilatory support for respiratory failure between September 2006 and March 2011. Of the patients included in the study, 86% were white, 52% were female, and the mean (SD) age was 59 (14) years. The patients had a mean (SD) Acute Physiology, Age and Chronic Health Evaluation III score of 63 (21.6) and a mean (SD) of 5.7 (6.4) study days. Self-initiated PDM (n = 126) with preferred selections tailored by a music therapist whenever desired while receiving ventilatory support, self-initiated use of noise-canceling headphones (NCH; n = 122), or usual care (n = 125). Daily assessments of anxiety (on 100-mm visual analog scale) and 2 aggregate measures of sedative exposure (intensity and frequency). Patients in the PDM group listened to music for a mean (SD) of 79.8 (126) (median [range], 12 [0-796]) minutes/day. Patients in the NCH group wore the noise-abating headphones for a mean (SD) of 34.0 (89.6) (median [range], 0 [0-916]) minutes/day. The mixed-models analysis showed that at any time point, patients in the PDM group had an anxiety score that was 19.5 points lower (95% CI, -32.2 to -6.8) than patients in the usual care group (P = .003). By the fifth study day, anxiety was reduced by 36.5% in PDM patients. The treatment × time interaction showed that PDM significantly reduced both measures of sedative exposure. Compared with usual care, the PDM group had reduced sedation intensity by -0.18 (95% CI, -0.36 to -0.004) points/day (P = .05) and had reduced frequency by -0.21 (95% CI, -0.37 to -0.05) points/day (P

  14. Statistical mechanics

    CERN Document Server

    Sheffield, Scott

    2009-01-01

    In recent years, statistical mechanics has been increasingly recognized as a central domain of mathematics. Major developments include the Schramm-Loewner evolution, which describes two-dimensional phase transitions, random matrix theory, renormalization group theory and the fluctuations of random surfaces described by dimers. The lectures contained in this volume present an introduction to recent mathematical progress in these fields. They are designed for graduate students in mathematics with a strong background in analysis and probability. This book will be of particular interest to graduate students and researchers interested in modern aspects of probability, conformal field theory, percolation, random matrices and stochastic differential equations.

  15. Selective condensation drives partitioning and sequential secretion of cyst wall proteins in differentiating Giardia lamblia.

    Directory of Open Access Journals (Sweden)

    Christian Konrad

    2010-04-01

    Full Text Available Controlled secretion of a protective extracellular matrix is required for transmission of the infective stage of a large number of protozoan and metazoan parasites. Differentiating trophozoites of the highly minimized protozoan parasite Giardia lamblia secrete the proteinaceous portion of the cyst wall material (CWM consisting of three paralogous cyst wall proteins (CWP1-3 via organelles termed encystation-specific vesicles (ESVs. Phylogenetic and molecular data indicate that Diplomonads have lost a classical Golgi during reductive evolution. However, neogenesis of ESVs in encysting Giardia trophozoites transiently provides basic Golgi functions by accumulating presorted CWM exported from the ER for maturation. Based on this "minimal Golgi" hypothesis we predicted maturation of ESVs to a trans Golgi-like stage, which would manifest as a sorting event before regulated secretion of the CWM. Here we show that proteolytic processing of pro-CWP2 in maturing ESVs coincides with partitioning of CWM into two fractions, which are sorted and secreted sequentially with different kinetics. This novel sorting function leads to rapid assembly of a structurally defined outer cyst wall, followed by slow secretion of the remaining components. Using live cell microscopy we find direct evidence for condensed core formation in maturing ESVs. Core formation suggests that a mechanism controlled by phase transitions of the CWM from fluid to condensed and back likely drives CWM partitioning and makes sorting and sequential secretion possible. Blocking of CWP2 processing by a protease inhibitor leads to mis-sorting of a CWP2 reporter. Nevertheless, partitioning and sequential secretion of two portions of the CWM are unaffected in these cells. Although these cysts have a normal appearance they are not water resistant and therefore not infective. Our findings suggest that sequential assembly is a basic architectural principle of protective wall formation and requires

  16. Rationale and study design of ViPS - variable pressure support for weaning from mechanical ventilation: study protocol for an international multicenter randomized controlled open trial

    NARCIS (Netherlands)

    Kiss, Thomas; Güldner, Andreas; Bluth, Thomas; Uhlig, Christopher; Spieth, Peter Markus; Markstaller, Klaus; Ullrich, Roman; Jaber, Samir; Santos, Jose Alberto; Mancebo, Jordi; Camporota, Luigi; Beale, Richard; Schettino, Guilherme; Saddy, Felipe; Vallverdú, Immaculada; Wiedemann, Bärbel; Koch, Thea; Schultz, Marcus Josephus; Pelosi, Paolo; de Abreu, Marcelo Gama

    2013-01-01

    In pressure support ventilation (PSV), a non-variable level of pressure support is delivered by the ventilator when triggered by the patient. In contrast, variable PSV delivers a level of pressure support that varies in a random fashion, introducing more physiological variability to the respiratory

  17. Sequential Release of Proteins from Structured Multishell Microcapsules.

    Science.gov (United States)

    Shimanovich, Ulyana; Michaels, Thomas C T; De Genst, Erwin; Matak-Vinkovic, Dijana; Dobson, Christopher M; Knowles, Tuomas P J

    2017-10-09

    In nature, a wide range of functional materials is based on proteins. Increasing attention is also turning to the use of proteins as artificial biomaterials in the form of films, gels, particles, and fibrils that offer great potential for applications in areas ranging from molecular medicine to materials science. To date, however, most such applications have been limited to single component materials despite the fact that their natural analogues are composed of multiple types of proteins with a variety of functionalities that are coassembled in a highly organized manner on the micrometer scale, a process that is currently challenging to achieve in the laboratory. Here, we demonstrate the fabrication of multicomponent protein microcapsules where the different components are positioned in a controlled manner. We use molecular self-assembly to generate multicomponent structures on the nanometer scale and droplet microfluidics to bring together the different components on the micrometer scale. Using this approach, we synthesize a wide range of multiprotein microcapsules containing three well-characterized proteins: glucagon, insulin, and lysozyme. The localization of each protein component in multishell microcapsules has been detected by labeling protein molecules with different fluorophores, and the final three-dimensional microcapsule structure has been resolved by using confocal microscopy together with image analysis techniques. In addition, we show that these structures can be used to tailor the release of such functional proteins in a sequential manner. Moreover, our observations demonstrate that the protein release mechanism from multishell capsules is driven by the kinetic control of mass transport of the cargo and by the dissolution of the shells. The ability to generate artificial materials that incorporate a variety of different proteins with distinct functionalities increases the breadth of the potential applications of artificial protein-based materials

  18. Striatal Neuropeptides Enhance Selection and Rejection of Sequential Actions

    Directory of Open Access Journals (Sweden)

    David Buxton

    2017-07-01

    Full Text Available The striatum is the primary input nucleus for the basal ganglia, and receives glutamatergic afferents from the cortex. Under the hypothesis that basal ganglia perform action selection, these cortical afferents encode potential “action requests.” Previous studies have suggested the striatum may utilize a mutually inhibitory network of medium spiny neurons (MSNs to filter these requests so that only those of high salience are selected. However, the mechanisms enabling the striatum to perform clean, rapid switching between distinct actions that form part of a learned action sequence are still poorly understood. Substance P (SP and enkephalin are neuropeptides co-released with GABA in MSNs preferentially expressing D1 or D2 dopamine receptors respectively. SP has a facilitatory effect on subsequent glutamatergic inputs to target MSNs, while enkephalin has an inhibitory effect. Blocking the action of SP in the striatum is also known to affect behavioral transitions. We constructed phenomenological models of the effects of SP and enkephalin, and integrated these into a hybrid model of basal ganglia comprising a spiking striatal microcircuit and rate–coded populations representing other major structures. We demonstrated that diffuse neuropeptide connectivity enhanced the selection of unordered action requests, and that for true action sequences, where action semantics define a fixed structure, a patterning of the SP connectivity reflecting this ordering enhanced selection of actions presented in the correct sequential order and suppressed incorrect ordering. We also showed that selective pruning of SP connections allowed context–sensitive inhibition of specific undesirable requests that otherwise interfered with selection of an action group. Our model suggests that the interaction of SP and enkephalin enhances the contrast between selection and rejection of action requests, and that patterned SP connectivity in the striatum allows the

  19. Programmable colloidal molecules from sequential capillarity-assisted particle assembly

    Science.gov (United States)

    Ni, Songbo; Leemann, Jessica; Buttinoni, Ivo; Isa, Lucio; Wolf, Heiko

    2016-01-01

    The assembly of artificial nanostructured and microstructured materials which display structures and functionalities that mimic nature’s complexity requires building blocks with specific and directional interactions, analogous to those displayed at the molecular level. Despite remarkable progress in synthesizing “patchy” particles encoding anisotropic interactions, most current methods are restricted to integrating up to two compositional patches on a single “molecule” and to objects with simple shapes. Currently, decoupling functionality and shape to achieve full compositional and geometrical programmability remains an elusive task. We use sequential capillarity-assisted particle assembly which uniquely fulfills the demands described above. This is a new method based on simple, yet essential, adaptations to the well-known capillary assembly of particles over topographical templates. Tuning the depth of the assembly sites (traps) and the surface tension of moving droplets of colloidal suspensions enables controlled stepwise filling of traps to “synthesize” colloidal molecules. After deposition and mechanical linkage, the colloidal molecules can be dispersed in a solvent. The template’s shape solely controls the molecule’s geometry, whereas the filling sequence independently determines its composition. No specific surface chemistry is required, and multifunctional molecules with organic and inorganic moieties can be fabricated. We demonstrate the “synthesis” of a library of structures, ranging from dumbbells and triangles to units resembling bar codes, block copolymers, surfactants, and three-dimensional chiral objects. The full programmability of our approach opens up new directions not only for assembling and studying complex materials with single-particle-level control but also for fabricating new microscale devices for sensing, patterning, and delivery applications. PMID:27051882

  20. Quantum random number generators

    Science.gov (United States)

    Herrero-Collantes, Miguel; Garcia-Escartin, Juan Carlos

    2017-01-01

    Random numbers are a fundamental resource in science and engineering with important applications in simulation and cryptography. The inherent randomness at the core of quantum mechanics makes quantum systems a perfect source of entropy. Quantum random number generation is one of the most mature quantum technologies with many alternative generation methods. This review discusses the different technologies in quantum random number generation from the early devices based on radioactive decay to the multiple ways to use the quantum states of light to gather entropy from a quantum origin. Randomness extraction and amplification and the notable possibility of generating trusted random numbers even with untrusted hardware using device-independent generation protocols are also discussed.

  1. Description and effects of sequential behavior practice in teacher education.

    Science.gov (United States)

    Sharpe, T; Lounsbery, M; Bahls, V

    1997-09-01

    This study examined the effects of a sequential behavior feedback protocol on the practice-teaching experiences of undergraduate teacher trainees. The performance competencies of teacher trainees were analyzed using an alternative opportunities for appropriate action measure. Data support the added utility of sequential (Sharpe, 1997a, 1997b) behavior analysis information in systematic observation approaches to teacher education. One field-based undergraduate practicum using sequential behavior (i.e., field systems analysis) principles was monitored. Summarized are the key elements of the (a) classroom instruction provided as a precursor to the practice teaching experience, (b) practice teaching experience, and (c) field systems observation tool used for evaluation and feedback, including multiple-baseline data (N = 4) to support this approach to teacher education. Results point to (a) the strong relationship between sequential behavior feedback and the positive change in four preservice teachers' day-to-day teaching practices in challenging situational contexts, and (b) the relationship between changes in teacher practices and positive changes in the behavioral practices of gymnasium pupils. Sequential behavior feedback was also socially validated by the undergraduate participants and Professional Development School teacher supervisors in the study.

  2. Can post-error dynamics explain sequential reaction time patterns?

    Directory of Open Access Journals (Sweden)

    Stephanie eGoldfarb

    2012-07-01

    Full Text Available We investigate human error dynamics in sequential two-alternative choice tasks. When subjects repeatedly discriminate between two stimuli, their error rates and mean reaction times (RTs systematically depend on prior sequences of stimuli. We analyze these sequential effects on RTs, separating error and correct responses, and identify a sequential RT tradeoff: a sequence of stimuli which yields a relatively fast RT on error trials will produce a relatively slow RT on correct trials and vice versa. We reanalyze previous data and acquire and analyze new data in a choice task with stimulus sequences generated by a first-order Markov process having unequal probabilities of repetitions and alternations. We then show that relationships among these stimulus sequences and the corresponding RTs for correct trials, error trials, and averaged over all trials are significantly influenced by the probability of alternations; these relationships have not been captured by previous models. Finally, we show that simple, sequential updates to the initial condition and thresholds of a pure drift diffusion model can account for the trends in RT for correct and error trials. Our results suggest that error-based parameter adjustments are critical to modeling sequential effects.

  3. A sequential point process model and Bayesian inference for spatial point patterns with linear structures

    DEFF Research Database (Denmark)

    Møller, Jesper; Rasmussen, Jakob Gulddahl

    We introduce a flexible spatial point process model for spatial point patterns exhibiting linear structures, without incorporating a latent line process. The model is given by an underlying sequential point process model, i.e. each new point is generated given the previous points. Under this model...... pattern exhibiting linear structures but where the exact mechanism responsible for the formations of lines is unknown. We illustrate this methodology by analyzing two spatial point pattern data sets (locations of bronze age graves in Denmark and locations of mountain tops in Spain) without knowing which...

  4. Sequential Window Diagnoser for Discrete-Event Systems Under Unreliable Observations

    Energy Technology Data Exchange (ETDEWEB)

    Wen-Chiao Lin; Humberto E. Garcia; David Thorsley; Tae-Sic Yoo

    2009-09-01

    This paper addresses the issue of counting the occurrence of special events in the framework of partiallyobserved discrete-event dynamical systems (DEDS). Developed diagnosers referred to as sequential window diagnosers (SWDs) utilize the stochastic diagnoser probability transition matrices developed in [9] along with a resetting mechanism that allows on-line monitoring of special event occurrences. To illustrate their performance, the SWDs are applied to detect and count the occurrence of special events in a particular DEDS. Results show that SWDs are able to accurately track the number of times special events occur.

  5. Fool's gold, lost treasures, and the randomized clinical trial.

    Science.gov (United States)

    Stewart, David J; Kurzrock, Razelle

    2013-04-16

    Randomized controlled trials with a survival endpoint are the gold standard for clinical research, but have failed to achieve cures for most advanced malignancies. The high costs of randomized clinical trials slow progress (thereby causing avoidable loss of life) and increase health care costs. A malignancy may be caused by several different mutations. Therapies effective vs one mutation may be discarded due to lack of statistical significance across the entire population. Conversely, expensive large randomized trials may have sufficient statistical power to demonstrate benefit despite the therapy only working in subgroups. Non-cost-effective therapy is then applied to all patients (including subgroups it cannot help). Randomized trials comparing therapies with different mechanisms of action are misleading since they may conclude the therapies are "equivalent" despite benefitting different subpopulations, or may erroneously conclude that one therapy is superior simply because it targets a larger subpopulation. Furthermore, minor variances in patient selection may determine study outcome, a therapy may be discarded as ineffective despite substantial benefit in one subpopulation if harmful in another, randomized trials may more effectively detect therapies with minor benefit in most patients vs marked benefit in subpopulations, and randomized trials in unselected patients may erroneously conclude that "shot-gun" combinations are superior to single agents when sequential administration of personalized single agents might work better and spare patients treatment with drugs that cannot help them. We must identify predictive biomarkers early by comparing responding to progressing patients in phase I-II trials. Enriching randomized trials for biomarker-positive patients can markedly reduce required patient numbers and costs despite expensive screening for biomarker-positive patients. Available data support approval of new drugs without randomized trials if they yield

  6. Quantum randomness and unpredictability

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, Gregg [Quantum Communication and Measurement Laboratory, Department of Electrical and Computer Engineering and Division of Natural Science and Mathematics, Boston University, Boston, MA (United States)

    2017-06-15

    Quantum mechanics is a physical theory supplying probabilities corresponding to expectation values for measurement outcomes. Indeed, its formalism can be constructed with measurement as a fundamental process, as was done by Schwinger, provided that individual measurements outcomes occur in a random way. The randomness appearing in quantum mechanics, as with other forms of randomness, has often been considered equivalent to a form of indeterminism. Here, it is argued that quantum randomness should instead be understood as a form of unpredictability because, amongst other things, indeterminism is not a necessary condition for randomness. For concreteness, an explication of the randomness of quantum mechanics as the unpredictability of quantum measurement outcomes is provided. Finally, it is shown how this view can be combined with the recently introduced view that the very appearance of individual quantum measurement outcomes can be grounded in the Plenitude principle of Leibniz, a principle variants of which have been utilized in physics by Dirac and Gell-Mann in relation to the fundamental processes. This move provides further support to Schwinger's ''symbolic'' derivation of quantum mechanics from measurement. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Group-sequential clinical trials with multiple co-objectives

    CERN Document Server

    Hamasaki, Toshimitsu; Evans, Scott R; Ochiai, Toshimitsu

    2016-01-01

    This book focuses on group sequential methods for clinical trials with co-primary endpoints based on the decision-making frameworks for: (1) rejecting the null hypothesis (stopping for efficacy), (2) rejecting the alternative hypothesis (stopping for futility), and (3) rejecting the null or alternative hypothesis (stopping for either futility or efficacy), where the trial is designed to evaluate whether the intervention is superior to the control on all endpoints. For assessing futility, there are two fundamental approaches, i.e., the decision to stop for futility based on the conditional probability of rejecting the null hypothesis, and the other based on stopping boundaries using group sequential methods. In this book, the latter approach is discussed. The book also briefly deals with the group sequential methods for clinical trials designed to evaluate whether the intervention is superior to the control on at least one endpoint. In addition, the book describes sample size recalculation and the resulting ef...

  8. Finding a Path for Segmentation Through Sequential Learning.

    Science.gov (United States)

    Wang, Hongzhi; Cao, Yu; Syed-Mahmood, Tanveer F

    2015-01-01

    Sequential learning techniques, such as auto-context, that applies the output of an intermediate classifier as contextual features for its subsequent classifier has shown impressive performance for semantic segmentation. We show that these methods can be interpreted as an approximation technique derived from a Bayesian formulation. To improve the effectiveness of applying this approximation technique, we propose a new sequential learning approach for semantic segmentation that solves a segmentation problem by breaking it into a series of simplified segmentation problems. Sequentially solving each of the simplified problems along the path leads to a more effective way for solving the original segmentation problem. To achieve this goal, we also propose a learning-based method to generate simplified segmentation problems by explicitly controlling the complexities of the modeling classifiers. We report promising results on the 2013 SATA canine leg muscle segmentation dataset.

  9. Optimal adaptive sequential designs for crossover bioequivalence studies.

    Science.gov (United States)

    Xu, Jialin; Audet, Charles; DiLiberti, Charles E; Hauck, Walter W; Montague, Timothy H; Parr, Alan F; Potvin, Diane; Schuirmann, Donald J

    2016-01-01

    In prior works, this group demonstrated the feasibility of valid adaptive sequential designs for crossover bioequivalence studies. In this paper, we extend the prior work to optimize adaptive sequential designs over a range of geometric mean test/reference ratios (GMRs) of 70-143% within each of two ranges of intra-subject coefficient of variation (10-30% and 30-55%). These designs also introduce a futility decision for stopping the study after the first stage if there is sufficiently low likelihood of meeting bioequivalence criteria if the second stage were completed, as well as an upper limit on total study size. The optimized designs exhibited substantially improved performance characteristics over our previous adaptive sequential designs. Even though the optimized designs avoided undue inflation of type I error and maintained power at ≥ 80%, their average sample sizes were similar to or less than those of conventional single stage designs. Copyright © 2015 John Wiley & Sons, Ltd.

  10. A Bayesian sequential processor approach to spectroscopic portal system decisions

    Energy Technology Data Exchange (ETDEWEB)

    Sale, K; Candy, J; Breitfeller, E; Guidry, B; Manatt, D; Gosnell, T; Chambers, D

    2007-07-31

    The development of faster more reliable techniques to detect radioactive contraband in a portal type scenario is an extremely important problem especially in this era of constant terrorist threats. Towards this goal the development of a model-based, Bayesian sequential data processor for the detection problem is discussed. In the sequential processor each datum (detector energy deposit and pulse arrival time) is used to update the posterior probability distribution over the space of model parameters. The nature of the sequential processor approach is that a detection is produced as soon as it is statistically justified by the data rather than waiting for a fixed counting interval before any analysis is performed. In this paper the Bayesian model-based approach, physics and signal processing models and decision functions are discussed along with the first results of our research.

  11. [Clinical observation of sequential occlusal adjustment for kinetic food impaction].

    Science.gov (United States)

    Xu, Juan; Fang, Bi-Song; Ma, Hong; Sun, Xiao-Qiang

    2009-12-01

    To study the effectiveness of sequential occlusal adjustment for kinetic food impaction. 36 patients who claiming food impaction with normal proximal contact were examined and analyzed about their occlusal relationship and configuration. Sequential occlusal adjustment was made to reduce pestle-mortar-like cusp, to create food escaping groove and to decrease mesial surface of the distal tooth cusp. One week, two weeks and six months later, the patients were reexamined and their oral conditions were evaluated. An elimination of food impaction was claimed for 32 patients in one week appointment and all 36 patients in two-week appointment. Six months later, no patient reported food impaction. The use of sequential occlusal adjustment results in an effective elimination of some kind of kinetic food impaction.

  12. Comparison Between Sequential Therapy and Modified Bismuth-Included Quadruple Therapy for Helicobacter pylori Eradication in Chinese Patients.

    Science.gov (United States)

    Yang, Xiuhong; Tan, Pengsheng; Song, Lianying; Lu, Zhanying

    To compare the efficacy and safety of sequential therapy and modified bismuth-included quadruple therapy as a first-line Helicobacter pylori eradication in China. The patients were randomized to receive sequential therapy [n = 90; rabeprazole (20 mg twice daily) and amoxicillin (1 g twice daily) for 5 days, followed by rabeprazole (20 mg twice daily), tinidazole (500 mg twice daily) plus clarithromycin (500 mg twice daily) for another 5 days] or modified bismuth-included quadruple therapy [n = 109; rabeprazole (20 mg twice daily), levofloxacin hydrochloride (400 mg twice daily), clarithromycin (500 mg twice daily), and colloidal bismuth pectin (200 mg 3 times a day) for 7 days]. A follow-up urea breath test was applied 4 weeks later. A total of 199 patients were diagnosed with H. pylori infection. The intention-to-treat and per-protocol (PP) eradication rates were 91.7% and 92.6%, respectively, in the modified bismuth-included quadruple therapy group, and 74.4% and 76.1%, respectively, in the sequential therapy group. The eradication rates were significantly higher in the modified bismuth-included quadruple therapy group, compared with the sequential therapy group (P = 0.001 for intention to treat and P = 0.001 for PP). Adverse effects were reported by patients from both groups, but the difference did not reach significant level (P = 0.280). The modified bismuth-included quadruple therapy seemed to be superior to the sequential therapy as the first-line regimen for H. pylori eradication in Chinese patients.

  13. Composite system reliability evaluation using sequential Monte Carlo simulation

    Science.gov (United States)

    Jonnavithula, Annapoorani

    Monte Carlo simulation methods can be effectively used to assess the adequacy of composite power system networks. The sequential simulation approach is the most fundamental technique available and can be used to provide a wide range of indices. It can also be used to provide estimates which can serve as benchmarks against which other approximate techniques can be compared. The focus of this research work is on the reliability evaluation of composite generation and transmission systems with special reference to frequency and duration related indices and estimated power interruption costs at each load bus. One of the main objectives is to use the sequential simulation method to create a comprehensive technique for composite system adequacy evaluation. This thesis recognizes the need for an accurate representation of the load model at the load buses which depends on the mix of customer sectors at each bus. Chronological hourly load curves are developed in this thesis, recognizing the individual load profiles of the customers at each load bus. Reliability worth considerations are playing an ever increasing role in power system planning and operation. Different methods for bus outage cost evaluation are proposed in this thesis. It may not be computationally feasible to use the sequential simulation method with time varying loads at each bus in large electric power system networks. Time varying load data may also not be available at each bus. This research work uses the sequential methodology as a fundamental technique to calibrate other non sequential methods such as the state sampling and state transition sampling techniques. Variance reduction techniques that improve the efficiency of the sequential simulation procedure are investigated as a part of this research work. Pertinent features that influence reliability worth assessment are also incorporated. All the proposed methods in this thesis are illustrated by application to two reliability test systems. In addition

  14. Pharmacokinetics of Voriconazole Administered Concomitantly with Fluconazole and Population-Based Simulation for Sequential Use ▿

    Science.gov (United States)

    Damle, Bharat; Varma, Manthena V.; Wood, Nolan

    2011-01-01

    In clinical practice, antifungal therapy may be switched from fluconazole to voriconazole; such sequential use poses the potential for drug interaction due to cytochrome P450 2C19 (CYP2C19)-mediated inhibition of voriconazole metabolism. This open-label, randomized, two-way crossover study investigated the effect of concomitant fluconazole on voriconazole pharmacokinetics in 10 subjects: 8 extensive metabolizers and 2 poor metabolizers of CYP2C19. The study consisted of 4-day voriconazole-only and 5-day voriconazole-plus-fluconazole treatments, separated by a 14-day washout. Voriconazole pharmacokinetics were determined by noncompartmental analyses. A physiologically based pharmacokinetic model was developed in Simcyp (Simcyp Ltd., Sheffield, United Kingdom) to predict the magnitude of drug interaction should antifungal therapy be switched from fluconazole to voriconazole, following various simulated lag times for the switch. In CYP2C19 extensive metabolizers, fluconazole increased the maximum plasma concentration and the area under the plasma concentration-time curve (AUC) of voriconazole by 57% and 178%, respectively. In poor metabolizers, however, voriconazole pharmacokinetics were unaffected by fluconazole. The simulations based on pharmacokinetic modeling predicted that if voriconazole was started 6, 12, 24, or 36 h after the last dose of fluconazole, the voriconazole AUC ratios (sequential therapy versus voriconazole only) after the first dose would be 1.51, 1.41, 1.28, and 1.14, respectively. This suggests that the remaining systemic fluconazole would result in a marked drug interaction with voriconazole for ≥24 h. Although no safety issues were observed during coadministration, concomitant use of fluconazole and voriconazole is not recommended. Frequent monitoring for voriconazole-related adverse events is advisable if voriconazole is used sequentially after fluconazole. PMID:21876043

  15. Trial sequential analysis reveals insufficient information size and potentially false positive results in many meta-analyses

    DEFF Research Database (Denmark)

    Brok, J.; Thorlund, K.; Gluud, C.

    2008-01-01

    OBJECTIVES: To evaluate meta-analyses with trial sequential analysis (TSA). TSA adjusts for random error risk and provides the required number of participants (information size) in a meta-analysis. Meta-analyses not reaching information size are analyzed with trial sequential monitoring boundaries...... analogous to interim monitoring boundaries in a single trial. STUDY DESIGN AND SETTING: We applied TSA on meta-analyses performed in Cochrane Neonatal reviews. We calculated information sizes and monitoring boundaries with three different anticipated intervention effects of 30% relative risk reduction (TSA......(30%)), 15% (TSA(15%)), or a risk reduction suggested by low-bias risk trials of the meta-analysis corrected for heterogeneity (TSA(LBHIS)). RESULTS: A total of 174 meta-analyses were eligible; 79 out of 174 (45%) meta-analyses were statistically significant (P

  16. Sequential and Multistep Substrate Interrogation Provides the Scaffold for Specificity in Human Flap Endonuclease 1

    KAUST Repository

    Sobhy, M.

    2013-06-06

    Human flap endonuclease 1 (FEN1), one of the structure-specific 5\\' nucleases, is integral in replication, repair, and recombination of cellular DNA. The 5\\' nucleases share significant unifying features yet cleave diverse substrates at similar positions relative to 5\\' end junctions. Using single-molecule Förster resonance energy transfer, we find a multistep mechanism that verifies all substrate features before inducing the intermediary-DNA bending step that is believed to unify 5\\' nuclease mechanisms. This is achieved by coordinating threading of the 5\\' flap of a nick junction into the conserved capped-helical gateway, overseeing the active site, and bending by binding at the base of the junction. We propose that this sequential and multistep substrate recognition process allows different 5\\' nucleases to recognize different substrates and restrict the induction of DNA bending to the last common step. Such mechanisms would also ensure the protection ofDNA junctions from nonspecific bending and cleavage. 2013 The Authors.

  17. Basic Results for Sequential Caputo Fractional Differential Equations

    Directory of Open Access Journals (Sweden)

    Bhuvaneswari Sambandham

    2015-03-01

    Full Text Available We have developed a representation form for the linear fractional differential equation of order q when 0 < q < 1, with variable coefficients. We have also obtained a closed form of the solution for sequential Caputo fractional differential equation of order 2q, with initial and boundary conditions, for 0 < 2q < 1. The solutions are in terms of Mittag–Leffler functions of order q only. Our results yield the known results of integer order when q = 1. We have also presented some numerical results to bring the salient features of sequential fractional differential equations.

  18. TELEGRAPHS TO INCANDESCENT LAMPS: A SEQUENTIAL PROCESS OF INNOVATION

    Directory of Open Access Journals (Sweden)

    Laurence J. Malone

    2000-01-01

    Full Text Available This paper outlines a sequential process of technological innovation in the emergence of the electrical industry in the United States from 1830 to 1880. Successive inventions that realize the commercial possibilities of electricity provided the foundation for an industry where technical knowledge, invention and diffusion were ultimately consolidated within th